Science.gov

Sample records for beijing etude physico-chimique

  1. Elaboration du Ge mesoporeux et etude de ses proprietes physico-chimiques en vue d'applications photovoltaiques

    NASA Astrophysics Data System (ADS)

    Tutashkonko, Sergii

    Le sujet de cette these porte sur l'elaboration du nouveau nanomateriau par la gravure electrochimique bipolaire (BEE) --- le Ge mesoporeux et sur l'analyse de ses proprietes physico-chimiques en vue de son utilisation dans des applications photovoltaiques. La formation du Ge mesoporeux par gravure electrochimique a ete precedemment rapportee dans la litterature. Cependant, le verrou technologique important des procedes de fabrication existants consistait a obtenir des couches epaisses (superieure a 500 nm) du Ge mesoporeux a la morphologie parfaitement controlee. En effet, la caracterisation physico-chimique des couches minces est beaucoup plus compliquee et le nombre de leurs applications possibles est fortement limite. Nous avons developpe un modele electrochimique qui decrit les mecanismes principaux de formation des pores ce qui nous a permis de realiser des structures epaisses du Ge mesoporeux (jusqu'au 10 mum) ayant la porosite ajustable dans une large gamme de 15% a 60%. En plus, la formation des nanostructures poreuses aux morphologies variables et bien controlees est desormais devenue possible. Enfin, la maitrise de tous ces parametres a ouvert la voie extremement prometteuse vers la realisation des structures poreuses a multi-couches a base de Ge pour des nombreuses applications innovantes et multidisciplinaires grace a la flexibilite technologique actuelle atteinte. En particulier, dans le cadre de cette these, les couches du Ge mesoporeux ont ete optimisees dans le but de realiser le procede de transfert de couches minces d'une cellule solaire a triple jonctions via une couche sacrificielle en Ge poreux. Mots-cles : Germanium meso-poreux, Gravure electrochimique bipolaire, Electrochimie des semi-conducteurs, Report des couches minces, Cellule photovoltaique

  2. La physique des bulles de champagne Une première approche des processus physico-chimiques liés à l'effervescence des vins de Champagne

    NASA Astrophysics Data System (ADS)

    Liger-Belair, G.

    2002-07-01

    bubbles collapsing at a free surface. But, to the best of our knowledge, and surprising as it may seem, no results concerning the collateral effects on adjoining bubbles of bubbles collapsing in a bubble monolayer have been reported up to now. Actually, effervescence in a glass of champagne ideally lends to a preliminary work with bubbles collapsing in a bubble monolayer. For a few seconds after pouring, the free surface is completely covered with a monolayer composed of quite monodisperse millimetric bubbles collapsing close to each others. We took high-speed photographs of the situation which immediately follows the rupture of a bubble cap in a bubble monolayer. Adjoining bubbles were found to be literally sucked and strongly stretched toward the lowest part of the cavity left by the bursting bubble, leading to unexpected and short-lived flower-shaped structures. Stresses in distorted bubbles (petals of the flower-shaped structure) were evaluated and found to be, at least, one order of magnitude higher than stresses numerically calculated in the boundary layer around an isolated single millimetric collapsing bubble. This is a brand-new and slightly counter-intuitive result. While absorbing the energy released during collapse, as an air-bag would do, adjoining bubble caps store this energy into their thin liquid film, leading finally to stresses much higher than those observed in the boundary layer around single millimetric collapsing bubbles. Further investigation should be conducted now, and especially numerically, in order to better understand the relative influence of each pertinent parameters (bubble size, liquid density and viscosity, effect of surfactant...) on bubble deformation. L'objectif général de cet ouvrage consacré à l'étude des processus physico- chimiques de l'effervescence des vins de Champagne était de décortiquer les différentes étapes de la vie d'une bulle de champagne en conditions réelles de consommation, dans une flûte. Nous r

  3. Boycott Beijing?

    ERIC Educational Resources Information Center

    Goldstein, Evan R.

    2008-01-01

    In the wake of China's harsh suppression of antigovernment protests in Tibet--among other human-rights abuses throughout its territory--world leaders have faced mounting pressure to boycott the opening ceremonies of the approaching Olympic Games in Beijing. The boycott has also become a hot topic on the presidential-campaign trail. John McCain and…

  4. Beijing Ancient Observatory

    NASA Astrophysics Data System (ADS)

    Shi, Yunli

    The Beijing Ancient Observatory is now the only complete example of an observatory from the seventeenth century in the world. It is a monument to the prosperity of astronomy in traditional China. Its instruments are emblems of the encounter and amalgamation of Chinese and European Science in the seventeenth and eighteenth centuries.

  5. ETUDE - European Trade Union Distance Education.

    ERIC Educational Resources Information Center

    Creanor, Linda; Walker, Steve

    2000-01-01

    Describes transnational distance learning activities among European trade union educators carried out as part of the European Trade Union Distance Education (ETUDE) project, supported by the European Commission. Highlights include the context of international trade union distance education; tutor training course; tutors' experiences; and…

  6. Cybersurfing after Beijing.

    PubMed

    1996-01-01

    The concept of technology as an activist tool was advanced at an Expert Group Workshop on Global Information through Computer Networking Technology held at United Nations (UN) headquarters in June 1996 as a follow-up to the Fourth World Conference on Women. Workshop participants assessed the potential for developing Women Watch, a core Internet space aimed at facilitating global information exchange for implementation of the Beijing Platform for Action. Women have been under-represented, both as users and producers, in electronic communication networking. It was recommended that Women Watch's priority should be to provide informational resources that could serve as an organizing tool and facilitate outreach activities. Information distributed through Women Watch should be global in scope, interactive, comprehensive, and linked to other existing resources. Available should be UN reports, regular government reports on National Action Plans, documents on gender issues, calendars of upcoming meetings, and background on groups involved in the Beijing conference. To ensure information dissemination, the Expert Group urged nongovernmental organization repackaging of information for illiterate populations or those without on-line facilities, information facilitators and local user support, and the delivery of appropriate hardware to networks and organizations. Finally, the experts recommended that a virtual or on-line global women's conference should be organized for the year 2000. PMID:12320533

  7. Haze over Beijing

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Thick haze collected over the Beijing region in late March 2007. Earlier that month, the BBC News reported that an international team of scientists had documented how increasing pollution in China led to decreasing rainfall over the region. The Moderate Resolution Imaging Spectroradiometer (MODIS) flying onboard the Aqua satellite captured these images of the Beijing region on March 22, 2007. The top image is a 'true-color' picture, similar to a digital photo. The bottom, 'false-color,' image uses a combination of visible and infrared light to more clearly show vegetation, water, and clouds. Even sparse vegetation appears bright green, while water appears deep blue (bright blue when tinged with sediment). Clouds dominated by water droplets appear white, while clouds made of ice crystals appear light blue. The false-color image highlights water bodies, perhaps aqua-culture ponds, that are all but invisible in the true-color image, especially along the shores of the Bo Hai. While vegetation and water show up more clearly in the false-color image, haze is much more transparent. Although dingy gray haze dominates the true-color picture, it is all but invisible in the false-color view. The haze 'disappears' in the infrared-enhanced image because tiny haze particles do not reflect longer-wavelength infrared light very well, making this type of image useful for distinguishing haze from clouds. The bank of clouds in the upper right corner shows up clearly in both pictures. As China industrializes, factories, power plants, and automobiles all contribute to pollution in the region. In examining pollutants and rainfall, the team of scientists examined records covering more than 50 years, concluding that pollution decreased precipitation at Mount Hua near Xi'an in central China. They concluded that when conditions are so hazy that visibility is reduced to less than 8 kilometers (5 miles), hilly precipitation can drop by 30 to 50 percent. When moist air passes over mountains

  8. The road from Beijing. IPPF.

    PubMed

    Brueggemann, I

    1999-12-01

    This article presents the speech of Ingar Brueggemann, Director General of the International Planned Parenthood Federation (IPPF) during the 149th Council on Population and Education meeting in October 1, 1999. She discussed the current situation of IPPF, its strategy, and expectations for Beijing+5, the UN review of the Fourth World Conference on Women. It was noted by the IPPF that some issues such as rape, family planning, and female genital mutilation, still need the establishment of legal solutions. Moreover, the Cairo Programme of Action has yet to address five critical areas of concern that relate directly to sexual and reproductive health: poverty, lack of education, lack of appropriate and high quality health care, violence, and human rights. She called for those working in the field to continue to be firm in their actions in order to implement the Cairo Programme of Action, and they have to be first class advocates for issues that Beijing stands for. PMID:12322392

  9. Spring Dust Storm Smothers Beijing

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A few days earlier than usual, a large, dense plume of dust blew southward and eastward from the desert plains of Mongolia-quite smothering to the residents of Beijing. Citizens of northeastern China call this annual event the 'shachenbao,' or 'dust cloud tempest.' However, the tempest normally occurs during the spring time. The dust storm hit Beijing on Friday night, March 15, and began coating everything with a fine, pale brown layer of grit. The region is quite dry; a problem some believe has been exacerbated by decades of deforestation. According to Chinese government estimates, roughly 1 million tons of desert dust and sand blow into Beijing each year. This true-color image was made using two adjacent swaths (click to see the full image) of data from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), flying aboard the OrbView-2 satellite, on March 17, 2002. The massive dust storm (brownish pixels) can easily be distinguished from clouds (bright white pixels) as it blows across northern Japan and eastward toward the open Pacific Ocean. The black regions are gaps between SeaWiFS' viewing swaths and represent areas where no data were collected. Image courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  10. Influence de l'alteration physique sur les caracteristiques physico-chimiques de monolithes de sols contamines traites par stabilisation/solidification au ciment

    NASA Astrophysics Data System (ADS)

    Remillard, Jonathan

    The concern of contaminated sites is affecting millions of property owner worldwide. As they pose a risk to the environment, human health or impair the value of buildings, remediation of contaminated sites has become an everyday issue. Stabilization/solidification (S/S) of contaminated soils with cement is a remediation technology that was developed to confine contaminants that cannot be degraded biologically, chemically or thermally by other technologies. Soils treated with S/S form a monolith that can be valorized on site. However, this practice is fairly uncommon in Quebec and this reluctance is partly due to the risks of degradation of the monoliths and the lack of knowledge relative to the long-term behavior of altered monoliths. The objective of this project was to simulate these degradations on cement-based monoliths of contaminated soils treated with S/S technology by causing physical alterations using different cycles of freeze/thawing and drying/wetting, and then to study the impact of these alterations on the mass losses, compressive strength, hydraulic conductivity, pH and leachability of five trace metals (Cd, Cr, Cu, Pb and Zn) used as contaminants. Various processes of S/S have been studied, either cement contents of 15 and 20%, then the presence of 5% by weight of calcium carbonate. For each S/S process formulated, the freeze/thaw cycles were much more effective in physically altering the monoliths. These alterations were mainly reflected by lower compressive strength, even more with lower cement contents. For their part, the drying/wetting cycles rather created a chemical change that lowered the pH of the monoliths. These chemical changes also affected the interpretation of leaching test results, especially for copper and zinc, since it was difficult to attribute effects to either physical or chemical alterations. The results showed that only chromium leached more clearly in response to physical alterations. All other elements studied were little affected, even though some samples were highly altered. This demonstrates that in some cases, damages may have little impact on long-term performance of the monoliths in terms of contaminant immobilization. However, integrating the study of long-term behaviors of monoliths in a process of formulation for contaminated soil treatment with S/S can become paramount, as seen for chromium in this present study. Keywords: stabilization / solidification, deterioration, alteration, leachability, contaminants.

  11. Modèle mathématique pour l'étude des équilibres physico-chimiques de permanentes.

    PubMed

    Chiodi, F

    1989-12-01

    Résumé La plupart des permanentes du commerce sont constituées d'acide thioglycolique (éventuellement associéà l'acide thiolactique), neutralisé par l'ammoniac, elles sont additionnées de carbonate d'ammonium comme tampon. Le système peut etre traité comme la neutralisation d'un mélange d'acides thioglycolique et carbonique par l'ammoniac, et il est complètement défini par trois paramètres, trois concentrations, ou deux concentrations et le pH, ou trois paramètres analytiques indépendants. Les calculs théoriques de l'équilibre sont compliqués du fait qu'il s'agit de l'équilibre de deux diacides faibles neutralisés par une base faible. Un modèle mathématique développé exclusivement par des équations théoriques permet l'interprétation des équilibres et la réalisation des calculs fiable pour la préparation des formules remplissant certaines caractéristiques. Le modèle permet de réaliser facilement des simulations en faisant varier les concentrations, les acides (par la voie des constantes de dissociation) ou d'associer différents acids et/ou bases organiques ou minérales. Une application complémentaire du modèle est de tracer la courbe dérivée à la courbe de neutralisation et de cette façon mesurer l'effet tampon en différents points par la mesure de sa pente. Synopsis Mathematical model for the study of physico-chemical equilibria in permanent wave solutions Most waving lotions on the market are prepared with thioglycolic acid (eventually associated with thiolactic acid) neutralized with ammonium hydroxide and buffered with ammonium bicarbonate. The system can be treated as the neutralization of a mix of carbonic acid and thioglycolic acid by ammonia and it is completely defined by three parameters: three concentrations; or two concentrations and pH; or three independent analytical parameters. Theoretical calculations of the equilibrium are difficult because the equilibrium involves at least two weak acids with a weak base. A mathematical model based exclusively on theoretical considerations allows the interpretation of equilibrium and performs accurate calculations of quantities of ingredients for preparations of permanent wave solutions satisfying special conditions. The model allows simulations by modifying concentrations, the acids (by using dissociation constants) or association between different acids and/or bases, organic or mineral. A complementary application of the model is the construction of a curve derived from the neutralization curve to evaluate the buffer effect at different points by the measure of the slope of the curve. PMID:19456957

  12. The photochemical smog pollution in Beijing

    SciTech Connect

    Xiaoyan Tang

    1996-12-31

    The photochemical smog pollution in summer time has been studied in Beijing area. The systematic field measurements associated with meteorological observation was conducted in 1986, 1987 and 1993. The spatial and temporal distribution of O{sub 3} and specific formation condition of photochemical smog, including vehicle emission sources and meteorological factors etc. in summer were studied and discussed. The prediction of O{sub 3} ambient air concentration in Beijing area in 2000, 2005 and 2010 by model simulation were also discussed.

  13. Migrant women: the path from Beijing.

    PubMed

    Barbero-baconnier, J

    1996-01-01

    This article discusses the statement of the UN International Office of Migration (IOM) delivered at the Fourth World Congress on Women held in Beijing in 1995. The Beijing Platform of Action identified migrants as comprising an estimated 125 million people. Half of the international migrants live in developing countries, and at least 50 million are women. Another 500 million are internal female migrants. Migration programs tend to marginalize female migrants and to ignore women's special needs and experiences. The Third World Conference in Nairobi in 1985 indicated that women migrants were more likely to suffer deprivation, hardship, isolation, loss of status, and discrimination. Women bear the burden of a family's daily life, are more vulnerable than men, and face additional problems in the work force. Women migrants are identified as dependents and must be sponsored for admission to the host country; they are often subjected to physical and sexual abuse and must face discrimination in a foreign environment. The special needs of migrant women must be addressed at every stage of the migration process: the decision making stage, the integration into host communities, and the reintegration upon return. Women must be empowered. IOM recently established the International Center for Migration and Health. This center will focus on special problems faced by women migrants and on migrants' rights. Between the Nairobi and Beijing conferences the plight of migrant women was not prominently addressed. Migration references were made in Beijing's Platform of Action in scattered places in the text. Governments need to provide gender-sensitive human rights education and training for public officials in order to fulfill the Beijing Platform. The IOM technical assistance to Argentina illustrates what cooperative ventures are possible. IOM has made important progress in implementing Beijing's Platform. PMID:12291794

  14. Research the Mechanism of Land Subsidence in Typical Area, Beijing

    NASA Astrophysics Data System (ADS)

    Liu, H.; Zhang, Y.; Wang, R.; Gu, Z.

    2014-12-01

    In recently years, the subsidence develop rapidly in Beijing. It can not be ignored the influence of the security of major project. Beijing Singapore city is located at the junction of Daxing and Hebei. The per captia water resources is 190m3.,far below the internationally safety limit 1000m3. The region is the dryland water resource and continued extraction groundwater caused land subsidence issue become increasingly prominent. With the Beijing Singapore city put into use, the amount of water shortages must further seriously and land subsidence subsidence area must be further increased. Therefore, monitor the land subsidence of Beijing Singapore city area and research its settlement mechanism, it is so important to ensure the safe operation of Beijing Singapore city . Explore the soil and water coupling mechanism of Beijing Singapore citya during land subsidence process, and optimize groundwater extraction program to ensure the safe operation of Beijing's second largest airport.

  15. Special Education in Beijing: An Overview.

    ERIC Educational Resources Information Center

    Nan, Deng Qing

    This paper describes special education for children with visual impairments, hearing impairments, and intellectual impairments in China, especially in the city of Beijing. It reports a long history of special schools for individuals with visual impairments (since 1874), noting curriculum components at one school for the blind including braille,…

  16. Reflections on Beijing: Meet the Lambacks

    ERIC Educational Resources Information Center

    Mushett, Travis

    2009-01-01

    This article reflects on the story of the Lambacks. Lantz Lamback is a gold medalist in the S7 cerebral palsy classification at the 2008 Paralympic Games in Beijing. Lantz can look intimidating; however, he is gentle and courteous. His family has been an important factor in Lantz's swimming career. For the Lambacks, Lantz's swimming is a family…

  17. Municipal solid waste management in Beijing City.

    PubMed

    Li, Zhen-shan; Yang, Lei; Qu, Xiao-Yan; Sui, Yu-mei

    2009-09-01

    This paper presents an overview of municipal solid waste (MSW) management in Beijing City. Beijing, the capital of China, has a land area of approximately 1368.32 km(2) with an urban population of about 13.33 million in 2006. Over the past three decades, MSW generation in Beijing City has increased tremendously from 1.04 million tons in 1978 to 4.134 million tons in 2006. The average generation rate of MSW in 2006 was 0.85 kg/capita/day. Food waste comprised 63.39%, followed by paper (11.07%), plastics (12.7%) and dust (5.78%). While all other wastes including tiles, textiles, glass, metals and wood accounted for less than 3%. Currently, 90% of MSW generated in Beijing is landfilled, 8% is incinerated and 2% is composted. Source separation collection, as a waste reduction method, has been carried out in a total of 2255 demonstration residential and commercial areas (covering about 4.7 million people) up to the end of 2007. Demonstration districts should be promoted over a wider range instead of demonstration communities. The capacity of transfer stations and treatment plants is an urgent problem as these sites are seriously overloaded. These problems should first be solved by constructing more sites and converting to new treatment technologies. Improvements in legislation, public education and the management of waste pickers are problematic issues which need to be addressed. PMID:19375298

  18. Genetic features of Mycobacterium tuberculosis modern Beijing sublineage

    PubMed Central

    Liu, Qingyun; Luo, Tao; Dong, Xinran; Sun, Gang; Liu, Zhu; Gan, Mingyun; Wu, Jie; Shen, Xin; Gao, Qian

    2016-01-01

    Mycobacterium tuberculosis (MTB) Beijing strains have caused a great concern because of their rapid emergence and increasing prevalence in worldwide regions. Great efforts have been made to investigate the pathogenic characteristics of Beijing strains such as hypervirulence, drug resistance and favoring transmission. Phylogenetically, MTB Beijing family was divided into modern and ancient sublineages. Modern Beijing strains displayed enhanced virulence and higher prevalence when compared with ancient Beijing strains, but the genetic basis for this difference remains unclear. In this study, by analyzing previously published sequencing data of 1082 MTB Beijing isolates, we determined the genetic changes that were commonly present in modern Beijing strains but absent in ancient Beijing strains. These changes include 44 single-nucleotide polymorphisms (SNPs) and two short genomic deletions. Through bioinformatics analysis, we demonstrated that these genetic changes had high probability of functional effects. For example, 4 genes were frameshifted due to premature stop mutation or genomic deletions, 19 nonsynonymous SNPs located in conservative codons, and there is a significant enrichment in regulatory network for all nonsynonymous mutations. Besides, three SNPs located in promoter regions were verified to alter downstream gene expressions. Our study precisely defined the genetic features of modern Beijing strains and provided interesting clues for future researches to elucidate the mechanisms that underlie this sublineage's successful expansion. These findings from the analysis of the modern Beijing sublineage could provide us a model to understand the dynamics of pathogenicity of MTB. PMID:26905026

  19. Beijing Olympics as an aerosol field experiment

    NASA Astrophysics Data System (ADS)

    Cermak, J.; Knutti, R.

    2009-05-01

    During the 2008 Olympic Summer Games, emission reductions were enforced in Beijing to improve air quality. Here we explore their effect on the regional aerosol load. We compare satellite-retrieved aerosol optical thickness (AOT) of that period with previous years, both in absolute terms and in a neural network approach taking into account the meteorological conditions. A statistically significant reduction of aerosol load is found in Beijing that decreases in magnitude and significance with increasing region size. Locally, the aerosol load (log(AOT)) was about 0.4 to 0.75 standard deviations below the levels expected for the prevailing meteorological situation. The small size of this effect relative to meteorological variability highlights the importance of regional aerosol transport.

  20. Beijing + 5, still much to be done.

    PubMed

    2000-07-01

    This paper presents the proceedings of the Twenty-third Special Session of the UN General Assembly entitled "Women 2000: gender equality, development and peace for the 21st century". Attended by representatives from 179 countries, UN agencies and 1200 nongovernmental organizations, the governments which came together reaffirmed their commitment to the goals and objectives contained in the Beijing Declaration and the Platform for Action adopted at the 4th World Conference on Women in 1995. Participants reviewed and appraised progress and identified obstacles and current challenges in the implementation of the Platform for Action. In addition, they recognized that the goals and commitments made in the Platform for Action have not been fully implemented and achieved. In view of this, a consensus was achieved which noted that further actions and initiatives at local, national, regional, and international levels to accelerate its implementation and to ensure that commitments for gender equality, development and peace are fully realized. An outcome of this meeting is the document entitled "Further actions and initiatives to implement the Beijing Declaration and the Platform for Action". The document presents the progress made since the 4th women's Conference in Beijing in 1995. PMID:12349728

  1. Plan for Reforming Beijing University's Engagements and Promotions System

    ERIC Educational Resources Information Center

    Chinese Education and Society, 2005

    2005-01-01

    This article reports about the plan for reforming Beijing university's engagements and promotion system. The leadership of Beijing University conducted in-depth deliberations on the university's work of building up its faculty contingent in light of the aim of establishing a world-class university and the situation and tasks faced in the current…

  2. Climatic impacts of urbanization on the Beijing

    NASA Astrophysics Data System (ADS)

    Yu, Miao

    2015-04-01

    WRF coupled UCM is used to simulate the climatic impacts from 2008 to 2012 of urbanization on the Beijing. The results show that simulation is generally well compared to the observation. The urbanization caused a strongest UHI in the night in urban areas. The precipitation is reduced slightly. The relative humidity has a more direct response to the urbanization process than precipitation. The effect of urbanization can heat the temperature up to 1.2 kilometers inside the urban boundary layer in the daytime. While for the nighttime, the UHI development height is less than 400 meters. The relative humidity is reduced below 800 meters in daytime in Beijing but is hardly changed in nighttime. Three different urban land use datasets include year 1990, 2000 and 2010 are used to set up three sensitive tests to find out that the real urbanization process has changed the surface energy balance with the sensible heat flux increase, latent heat flux decrease and ground heat flux increase, causing the increase of temperature which forms the UHI. Both the changes of sensible heat flux and latent heat flux is more pronounced in the time period of 2000 to 2010 than that of 1990 to 2000. Twenty years from1990 to 2010 urbanization can enhance the UHI about 3.5˚C, among which the 2000-2010 period urbanization has attributed over 68%. The latest ten years urbanization process has a much pronounced impact on the UHI.

  3. Clinical Impact of Mycobacterium tuberculosis W-Beijing Genotype Strain Infection on Aged Patients in Taiwan▿

    PubMed Central

    Feng, Jia-Yih; Su, Wei-Juin; Tsai, Cheng-Chien; Chang, Shi-Chuan

    2008-01-01

    The impact of W-Beijing genotype Mycobacterium tuberculosis on treatment outcome was evaluated in 249 newly diagnosed tuberculosis patients. No significant difference in the treatment outcome was found between the W-Beijing and non-W-Beijing groups. However, a poor outcome was more common in the elderly patients (≥65 years) infected with the W-Beijing strain. PMID:18596137

  4. Phospholipase C in Beijing strains of Mycobacterium tuberculosis

    PubMed Central

    Mirsamadi, ES; Farnia, P; Jahani Sherafat, S; Esfahani, M; Faramarzi, N

    2010-01-01

    Background and Objectives Phospholipase of Mycobacterium tuberculosis plays an important role in pathogenesis through breaking up phospholipids and production of diacylglycerol. In this study, we examined the Beijing strains of Mycobacterium tuberculosis isolated from Iranian patients for the genes encoding this enzyme. Materials and Methods DNA extraction was performed using CTAB (cetyltrimethylammonium bromide) from positive culture specimens in tuberculosis patients. PCR was then used to amplify the plcA, plcB, plcC genes of Beijing strain, and non-Beijing strains were identified by spoligotyping. Results Of 200 specimens, 19 (9.5%) were Beijing strain and 181 (90.5%) were non-Beijing strains. The results of PCR for Beijing strains were as follows: 16 strains (84.2%) were positive for plcA, 17 (89.4%) were positive for plcB and 17 (89.4%) were positive for plcC genes. The standard strain (H37RV) was used as control. Conclusion The majority of Beijing strains have phospholipase C genes which can contribute to their pathogenesis but we need complementary studies to confirm the role of phospholipase C in pathogenecity of Mycobacterium tuberculosis. PMID:22347572

  5. Polycyclic aromatic hydrocarbons residues in sandstorm depositions in Beijing, China.

    PubMed

    Fu, S; Li, K; Xia, X J; Xu, X B

    2009-02-01

    This study was conducted to determine the concentration of 16 polycyclic aromatic hydrocarbons (PAHs) in sandstorm depositions in Beijing, China. The PAH concentrations in 13 samples collected in Beijing ranged from 0.18 to 3.52 microg g(-1). Analysis of the sources of contamination revealed that the PAHs were derived from a coal combustion source, although various effects of traffic emissions were also observed. Furthermore, the PAH levels in Beijing tended to be higher in the southeast. Finally, the nemerow composite index revealed that the degree of pollution in the sandstorm depositions varied widely among sampling sites. PMID:18773130

  6. Microtremor array measurement in Metropolitan Beijing

    NASA Astrophysics Data System (ADS)

    Wang, W.; Liu, L.; Chen, Q.; Rohrbach, E.

    2007-12-01

    High-resolution near-surface geologic information is essential for seismic hazard reduction in urban areas. Traditionally, a seismic source within the area of study is always desirable for getting the high-resolution information. However, natural earthquake does not usually conveniently occur during periods of seismic observation. Meanwhile, explosive and/or vibrating sources are prohibited to be used in cities. To overcome these limitations for addressing urban seismic hazard reduction, microtremors, the ambient noise of micro-motions in the ground, are becoming valuable sources for extracting the much needed earthquake engineering parameters in urban settings. Using 30 three-component seismometers we have collected microtremor data at more than 1,000 sites in metropolitan Beijing area in the summer of 2007. The data were collected in two ways: 1) along two major roads running roughly orthogonal in NW and NE directions centered in the city center with 200-m seismometer spacing and minimum measurement duration of 1 hour; and 2) seismometer spacing of approximately 1-km that covered the entire area inside Beijing's 5th Beltway. The data are processed with both the horizontal to vertical spectral ratio method (H/V) and space correlation method. The delineated shear wave velocity and the bedrock interface mapping are compared with results by other means. Meanwhile, the newly obtained information on ground motion fundamental frequency and amplification factor will provide further constraints on seismic hazard analysis to those critical structures of the 2008 Summer Olympic Game. This project is supported by the Ministry of Science and Technology of China.

  7. La physique des bulles de champagne Une première approche des processus physico-chimiques liés à l'effervescence des vins de Champagne

    NASA Astrophysics Data System (ADS)

    Liger-Belair, G.

    2002-07-01

    People have long been fascinated by bubbles and foams dynamics, and since the pioneering work of Leonardo da Vinci in the early 16th century, this subject has generated a huge bibliography. However, only very recently, much interest was devoted to bubbles in Champagne wines. Small bubbles rising through the liquid, as well as a bubble ring (the so-called collar) at the periphery of a flute poured with champagne are the hallmark of this traditionally festive wine, and even there is no scientific evidence yet to connect the quality of a champagne with its effervescence, people nevertheless often make a connection between them. Therefore, since the last few years, a better understanding of the numerous parameters involved in the bubbling process has become an important stake in the champagne research area. Otherwise, in addition to these strictly enological reasons, we also feel that the area of bubble dynamics could benefit from the simple but close observation of a glass poured with champagne. In this study, our first results concerning the close observation of the three main steps of a champagne bubble's life are presented, that is, the bubble nucleation on tiny particles stuck on the glass wall (Chap. 2), the bubble ascent through the liquid (Chap. 3), and the bursting of bubbles at the free surface, which constitutes the most intriguing and visually appealing step (Chap. 4). Our results were obtained in real consuming conditions, that is, in a classical crystal flute poured with a standard commercial champagne wine. Champagne bubble nucleation proved to be a fantastic everyday example to illustrate the non-classical heterogeneous bubble nucleation process in a weakly supersaturated liquid. Contrary to a generally accepted idea, nucleation sites are not located on irregularities of the glass itself. Most of nucleation sites are located on tiny hollow and roughly cylindrical exogenous fibres coming from the surrounding air or remaining from the wiping process. Because of their geometry and hydrophobic properties, such particles are able to entrap gas pockets during the filling of a flute and to start up the bubble production process. Such particles are responsible for the clockwork and repetitive production of bubbles that rise in-line into the form of elegant bubble trains. This cycle of bubble production at a given nucleation site is characterised by its bubbling frequency. The time needed to reach the moment of bubble detachment depends on the kinetics of the CO2 molecules transfer from the champagne to the gas pocket, but also on the geometrical properties of the given nucleation site. Now, since a collection of particle shapes and sizes exists on the glass wall, the bubbling frequency may also vary from one site to another. Three minutes after pouring, we measured bubbling frequencies ranging from less than 1 Hz up to almost 30 Hz, which means that the most active nucleation sites emit up to 30 bubbles per second. After their detachment from nucleation sites, champagne bubbles rise in-line through the liquid into the form of elegant bubble trains. Since they collect dissolved carbon dioxide molecules, champagne bubbles expand during ascent and therefore constitute an original tool to investigate the dynamics of rising and expanding bubbles. Hydrodynamically speaking, champagne bubbles were found to reach a quasi-stationary stage intermediate between that of a rigid and that a fluid sphere (but nevertheless closer to that of a fluid sphere). This result drastically differs from the result classically observed with bubbles of fixed radii rising in surfactant solutions. Since surfactants progressively adsorb at the bubble surface during the rise, the drag coefficient of a rising bubble of fixed radius progressively increases, and finally reaches the rigid sphere limit when the bubble interface gets completely contaminated. In the case of champagne, since a bubble expands during its rise through the supersaturated liquid, the bubble interface continuously increases and therefore continuously offers newly created surface

  8. [A brief history of Beijing Shijitan(Century Altar) Hospital].

    PubMed

    Cao, C F; Wen, Z

    2016-01-28

    Founded in 1914, the Jing-Han Railway Hospital has undergone through four different stages during its 100 years' transition, viz., from 1914 to 1949, from 1949 to 1979, from 1980 to 2003 and from 2004 to the present, with its title changing from Peking-Hankou Railway Hospital, Beijing Health Care Station, Peiping Railway Hospital, Beijing Railway General Hospital and today's Beijing Shijitan Hospital. As a railway hospital, in addition to offering services to Chinese railway health, it has also participated in many public welfare activities, such as major disaster rescues, important domestic medical services, the international medical assistance, hospitals' counterpart support, Lifeline Express and so on.In a sense, the establishment and development of the hospital are connected with Beijing Railway Health Services and is not only closely related with China's railway healthcare, but also to modern social transformation and changes. PMID:27049744

  9. PM10 modeling of Beijing in the winter

    NASA Astrophysics Data System (ADS)

    Song, Yu; Zhang, Minsi; Cai, Xuhui

    The megacity of Beijing, China, has had an air pollution problem since the 1990s. The concentrations of particulate matter with an aerodynamic diameter less than 10 μm (PM10) in Beijing in the winter of 2000 were high; the average value of 188 μg m -3 was nearly four times the first grade national standard of 50 μg m -3. The CALPUFF modeling system was used to simulate PM10 dispersion from 1 January 2000 to 29 February 2000. We used near real-time landcover data from the moderate resolution imaging spectroradiometer (MODIS). Statistical evaluation indicated that the model agreed well with the observations. The fluctuations of 24-h PM10 concentrations followed the winter synoptic winds. Cold air from the northwest or north intruded over Beijing for average periods of 4 days in winter, accompanied by high wind speeds. PM10 was swept out of Beijing after the cold fronts and accumulated again once the winds stopped, until the next cold air intrusion. Capital Steel Corporation Limited contributed 46% of the PM10 mass concentrations observed in the Shijingshan industrial area, and had little effect on the eastern part or the center of Beijing. The other industrial regions distributed in southeastern Beijing accounted for an average of 18% of the PM10 in Beijing. Boilers associated with coal consumption mostly for winter heating contributed 31%. Motor vehicles and road dust contributed 5% and 13%, respectively. The total of residential heating in old houses and restaurants contributed approximately 7%. The primary PM10 emissions from electrical generating units were relatively low. Some suggestions are proposed for reducing PM10 pollution in Beijing.

  10. Options of sustainable groundwater development in Beijing Plain, China

    NASA Astrophysics Data System (ADS)

    Zhou, Yangxiao; Wang, Liya; Liu, Jiurong; Li, Wenpeng; Zheng, Yuejun

    Overexploitation of groundwater resources has supported rapid social and economical developments in Beijing City in last 30 years. The newly constructed emergency well fields have saved Beijing from a critical water crisis caused by a long drought spell of eight consecutive years from 1999 to 2006. But this unsustainable development has resulted in serious consequences: discharges to rivers ceased, large number of pumping wells went dry, and land subsidence caused destruction of underground infrastructure. The completion of the middle route of South to North water transfer project to transfer water from Yangtze river to Beijing City by 2010 provides opportunity to reverse the trend of groundwater depletion and to achieve a long-term sustainable development of groundwater resources in Beijing Plain. Four options of groundwater development in Beijing Plain were formulated and assessed with a regional transient groundwater flow model. The business as usual scenario was used as a reference for the comparative analysis and indicates fast depletion of groundwater resources. The reduction of abstraction scenario has immediate and fast recovery of groundwater levels, especially at the cone of depression. The scenario of artificially enhanced groundwater recharge would replenish groundwater resources and maintain the capacity of present water supply well fields. The combined scenario of the reduction of abstraction and the increase of recharge could bring the aquifer systems into a new equilibrium state in 50 years. A hydrological sustainability of groundwater resources development could then be achieved in Beijing Plain.

  11. Potential health benefits of controlling dust emissions in Beijing.

    PubMed

    Meng, Jing; Liu, Junfeng; Fan, Songmiao; Kang, Chuyun; Yi, Kan; Cheng, Yanli; Shen, Xing; Tao, Shu

    2016-06-01

    Although the adverse impact of fine particulate matter (i.e., PM2.5) on human health has been well acknowledged, little is known of the health effects of its specific constituents. Over the past decade, the annual average dust concentrations in Beijing were approximately ∼14 μg m(-3), a value that poses a great threat to the city's 20 million residents. In this study, we quantify the potential long-term health damages in Beijing resulting from the dust exposure that occurred from 2000 to 2011. Each year in Beijing, nearly 4000 (95% CI: 1000-7000) premature deaths may be associated with long-term dust exposure, and ∼20% of these deaths are attributed to lung cancer. A decomposition analysis of the inter-annual variability of premature deaths in Beijing indicates that dust concentrations determine the year-to-year tendency, whereas population growth and lung cancer mortality rates drive the increasing tendency of premature death. We suggest that if Beijing takes effective measures towards reducing dust concentrations (e.g., controlling the resuspension of road dust and the fugitive dust from construction sites) to a level comparable to that of New York City's, the associated premature deaths will be significantly reduced. This recommendation offers "low-hanging fruit" suggestions for pollution control that would greatly benefit the public health in Beijing. PMID:27038572

  12. Resistance to cellular autophagy by Mycobacterium tuberculosis Beijing strains.

    PubMed

    Haque, Md Fazlul; Boonhok, Rachasak; Prammananan, Therdsak; Chaiprasert, Angkana; Utaisincharoen, Pongsak; Sattabongkot, Jetsumon; Palittapongarnpim, Prasit; Ponpuak, Marisa

    2015-10-01

    Autophagy represents a key pathway in innate immune defense to restrict Mycobacterium tuberculosis growth inside host macrophages. Induction of autophagy has been shown to promote mycobacterial phagosome acidification and acquisition of lysosomal hydrolases, resulting in the elimination of intracellular M. tuberculosis reference strains such as H37Rv. The notorious Beijing genotype has been previously shown to be hyper-virulent and associated with increased survival in host cells and a high mortality rate in animal models, but the underlying mechanism that renders this family to have such advantages remains unclear. We hypothesize that autophagic control against M. tuberculosis Beijing strains may be altered. Here, we discovered that the Beijing strains can resist autophagic killing by host cells compared with that of the reference strain H37Rv and a strain belonging to the East African Indian genotype. Moreover, we have determined a possible underlying mechanism and found that the greater ability to evade autophagic elimination possessed by the Beijing strains stems from their higher capacity to inhibit autophagolysosome biogenesis upon autophagy induction. In summary, a previously unrecognized ability of the M. tuberculosis Beijing strains to evade host autophagy was identified, which may have important implications for tuberculosis treatment, especially in regions prevalent by the Beijing genotype. PMID:26160686

  13. [Observations and comparison analysis of air pollution in Beijing and nearly surrounding areas during Beijing 2008 Olympic Games].

    PubMed

    Sun, Zhi-Qiang; Ji, Dong-Sheng; Song, Tao; Lin, Hong; Wang, Yue-Si; Jiang, Chang-Sheng

    2010-12-01

    In order to study regional air quality, evaluate the interaction of air quality among Beijing and four cities and assess the effects of regional collaborative emission abatement in Beijing and surrounding areas for the Olympic Games period on regional air quality, and seek an effective means of early warning of air pollution, a monitoring network on observation of atmospheric pollutants in Beijing and four nearby cities which were Zhuozhou, Langfang, Xianghe and Yanjiao, was established to measure concentrations of NO(x), O3 and particulate matter in June 2008. The results show that the primary pollutants in Beijing and nearly surrounding areas are particulates during the study periods. The average mass concentrations of PM10 were (114 +/- 66) microg/m3 and (128 +/- 59) microg/m3 in Beijing and nearby cities, respectively, while the average mass concentrations of PM2.5 were (77 +/- 47) microg/m3 and (81 +/- 51) microg/m3, respectively. The average maximum hourly mass concentrations of O3 were (164 +/- 52) microg/m3 and (165 +/- 55) microg/m3, as well as the average mass concentrations of NO(x) were (58 +/- 23) microg/m3 and (25 +/- 14) microg/m3 in Beijing and nearby cities, respectively. Compared to June, concentrations of PM10, PM2.5, O3, NO(x) decreased by 69%, 62%, 18% and 41% during the Olympic period (from August 8 to 24) and 56%, 49%, 17% and 16% during the Paralympic Games period (from September 6 to 17) in Beijing. The mass concentration of PM2.5 was affected by the surrounding areas of Beijing seriously. The relative high concentrations of NO(x) in Beijing implied NO(x) had the potential tendency to be transported to the surrounding areas. Ozone showed regional pollution characteristics in summer. It shows that the monitoring network on observation of atmospheric pollutants in Beijing and nearly surrounding areas is significant in early warning of air pollution, and could provide scientific support for interregional cooperation of air pollution control

  14. Polychlorinated biphenyl residues in sandstorm depositions in Beijing, China.

    PubMed

    Fu, Shan; Yang, Zhong-Zhi; Li, Ke; Xu, Xiao-Bai

    2008-10-01

    Sandstorms, which distribute many particles, are a special atmospheric occurrence and are frequent in northern China. We conducted this study to determine, for the first time, the concentration of polychlorinated biphenyls (PCBs) in sandstorm depositions. We collected 13 samples from urban areas of Beijing, and we measured a total of 144 PCB congeners. Thirteen samples all contained PCB residues. The total PCB concentration ranged from 1.6 to 15.6ngg(-1) (median, 4.8ngg(-1), dry weight), with trichlorinated biphenyls as the predominant homologue (>50.4%). Furthermore, we observed increasing PCB contamination from northwest to east Beijing. We later explored possible factors affecting contamination of the sandstorm depositions, which revealed a significant correlation between SigmaPCBs and the minimum particle size of the sandstorm deposition samples. Principal-component analysis revealed that the major source of PCBs in Beijing may be potentially associated with the number-one commercial PCB through the long-range transmission. In previous results, PCBs were not a severe component of contamination in sandstorm depositions of Beijing. However, this study suggested that sandstorm deposition may be a potential source of exposure to PCBs for the residents of Beijing, China. PMID:18674798

  15. Land-use suitability analysis for urban development in Beijing.

    PubMed

    Liu, Renzhi; Zhang, Ke; Zhang, Zhijiao; Borthwick, Alistair G L

    2014-12-01

    Land-use suitability analyses are of considerable use in the planning of mega-cities. An Urban Development Land-use Suitability Mapping (UDLSM) approach has been constructed, based on opportunity and constraint criteria. Two Multi-criteria Evaluation (MCE) methods, the Ideal Point Method (IPM) and Ordered Weighted Averaging (OWA), were used to generate the opportunity map. The protection map was obtained by means of constraint criteria, utilizing the Boolean union operator. A suitability map was then generated by overlaying the opportunity and protection maps. By applying the UDLSM approach to Beijing, its urban development land-use suitability was mapped, and a sensitivity analysis undertaken to examine the robustness of the proposed approach. Indirect validation was achieved by mutual comparisons of suitability maps resulting from the two MCE methods, where the overall agreement of 91% and kappa coefficient of 0.78 indicated that both methods provide very similar spatial land-use suitability distributions. The suitability level decreases from central Beijing to its periphery, and the area classed as suitable amounts to 28% of the total area. Leading attributes of each opportunity factor for suitability were revealed, with 2256 km(2), i.e. 70%, of existing development land being overlaid by suitable areas in Beijing. Conflicting parcels of land were identified by overlaying the resultant map with two previous development blueprints for Beijing. The paper includes several recommendations aimed at improving the long-term urban development plans for Beijing. PMID:25036557

  16. Medical care delivery at the Beijing 2008 Olympic Games

    PubMed Central

    Zhang, Jin-jun; Wang, Li-dong; Chen, Zhi; Ma, Jun; Dai, Jian-ping

    2011-01-01

    BACKGROUND: Beijing successfully hosted the 2008 Olympic Games, and the services including medical services were widely appreciated by both participants and visitors. We retrospectively analyzed the quality of the medical services provided to athletes, spectators, VIPs, and the workforce during the Beijing 2008 Olympic Games. The information thus gathered would be useful for planning strategies for managing mass gatherings. METHODS: Medical encounter forms filled during the Beijing 2008 Olympic Games were retrospectively reviewed. Descriptive statistics was used to characterize the data by accreditation and diagnostic categories. RESULTS: A total of 22 892 medical encounters were documented during the Beijing 2008 Olympic Games. Among them, 10 549 (46.08%) involved the workforce, 3 365 (14.70%) athletes, 3 019 (13.19%) spectators, 585 (2.56%) members of the media, 1 065 (4.65%) VIPs, and 4 309 (18.82%) others. Of the 22 892 cases, physical injury accounted for 27.90% (6 386), respiratory disease 18.21% (4 169), and heat-related illnesses 2.68% (615). CONCLUSIONS: Preparations of the medical service for the Beijing 2008 Olympic Games were made for 7 years, and the service provided has been praised worldwide. This study provides valuable information that may be useful for planning medical services for upcoming Olympic Games, including the London 2012 Olympic Games and other mass gatherings. PMID:25215021

  17. Etude theorique des fluctuations structurales dans les composes organiques a dimensionnalite reduite

    NASA Astrophysics Data System (ADS)

    Dumoulin, Benoit

    Les systemes a dimensionnalite reduite constituent maintenant une branche entiere de la physique de la matiere condensee. Cette derniere s'est developpee rapidement au cours des dernieres annees, avec la decouverte des materiaux organiques qui presentent, justement, des proprietes physiques fortement anisotropes. Cette these presente une etude en trois parties de plusieurs composes organiques qui, bien que tres differents du point de vue de leurs compositions chimiques et de leurs proprietes physiques a haute temperature, subissent tous une instabilite structurale a tres basse temperature. De plus, dans chacun des cas, l'instabilite structurale est precedee d'un important regime fluctuatif a partir duquel les proprietes physiques changent de maniere significative. Notre etude suit un ordre chronologique inverse puisque nous nous attardons en premier lieu au cas de composes recemment decouverts: les composes de la famille des (BCPTTF)2X (X = PF6 , AsF6). Ces derniers sont des isolants magnetiques a la temperature ambiante et subissent une instabilite structurale de type spin-Peierls a une temperature appelee TSP. En particulier, nous nous interessons a l'etude des proprietes physiques de ces systemes dans le regime fluctuatif, qui precede cette instabilite. Notre etude theorique nous permet de comprendre en detail comment ces systemes s'approchent de l'instabilite struturale. Dans la seconde partie de cette these, nous etudions le regime fluctuatif (pre-transitionnel) observe experimentalement dans le compose de (TMTTF)2PF6. Ce compose organique, dont la structure s'apparente aux sels de Bechgaard, subit une instabilite de type spin-Peierls a une temperature T SP = 19K. Bien que ce compose possede la particularite d'etre un bon conducteur a la temperature ambiante, il subit une transition de type Mott-Hubbard a une temperature Trho ≈ 220K et devient alors un isolant magnetique, analogue aux composes de la famille des (BCPTTF)2X. Le regime fluctuatif precedant l

  18. Fracture patterns in synclinal folds, Miaofengshan, Beijing

    NASA Astrophysics Data System (ADS)

    Liu, X. Z.; Liao, Z.; Reches, Z.

    2014-12-01

    The anticlinal bends are of interest for the oil/gas exploration and drilling designs as they are structural traps associated with high intensity of natural fractures due to bending curvature extension. However, some petroliferous areas with proven oil reserves were identified in synclinal structures, e.g. Songliao, Ordos and Bohai Bay Basins, northeast China, Bonaparte Basin, Australia, and Santa Maria Valley field, California. We analyze the fractures in synclines that are expected to carry curvature related fractures similarly to anticlines. The analysis is conducted on a 500m long and ~300 tall exposure of a folded sequence of dolomite and limestone layers at Miaofengshan, Beijing. Two general fracture groups are recognized: (1) layer crossing joints that are sub-parallel to the syncline axial surface; and (2) a distinct system of extension veins, which are joints filled with secondary calcite, that was found only in two layers of 0.8 and 2.2 m thick. These veins are layer-bound, they are up to 5 cm wide, and their width tapers toward the top and bottom of the host layers. Most of them are oriented normal to the bedding surfaces and radially with respect to the syncline shape. We recognized two phases of secondary mineralization that indicate layer-parallel extension of 5% or more. Apparently, these veins developed by bending extension of the most brittle layers whereas the more ductile layers above and below extended quasi-continuously. The analysis suggests that synclinal fracturing should be considered as possible mechanism for exploration of unconventional.

  19. After Beijing: emphasis on poverty eradication.

    PubMed

    1996-01-01

    In March 1996, during its first meeting since the Fourth World Conference on Women, the UN Commission on the Status of Women (CSW), called for a gender perspective to be integrated into policies and programs dealing with poverty, child and dependent care, and the media. Three expert panels examined each of these areas through a format which encouraged dialogue and led to the adoption of 17 resolutions, decisions, and agreed conclusions as well as a recommendation that the UN adopt a multi-year work program for the CSW to allow it to review progress in elimination of the 12 main obstacles to women's advancement identified at Beijing. Among the resolutions adopted by the CSW were calls to 1) take a broad and integrated approach to poverty eradication, 2) enhance women's empowerment and autonomy, 3) promote equity and equality in the public domain, 4) promote women's employment, 5) give women social and economic protection when they are unable to work, 6) counteract negative images of women and sex-stereotyping in the media, 7) reduce the representation of violence against women in the media, 8) strengthen the role of women in global communications, 9) encourage the participation of men in child and dependent care, and 10) recognize women's double burden of work. The CSW also agreed to pursue further discussions about drafting an optional protocol to the 1979 Convention on the Elimination of All Forms of Discrimination Against Women. Among its other actions, the CSW called for mechanisms to protect the rights of women migrant workers, to protect women and children during armed conflicts, to include gender-based human rights violations in UN activities, and to address the root factors which lead to social ills such as trafficking in women and girls. In addition, the CSW submitted a draft resolution demanding that Israel protect the rights of Palestinian women and their families. PMID:12291684

  20. Deafness gene mutations in newborns in Beijing.

    PubMed

    Han, Shujing; Yang, Xiaojian; Zhou, Yi; Hao, Jinsheng; Shen, Adong; Xu, Fang; Chu, Ping; Jin, Yaqiong; Lu, Jie; Guo, Yongli; Shi, Jin; Liu, Haihong; Ni, Xin

    2016-05-01

    Objective To determine the incidence of congenital hearing loss (HL) in newborns by the rate of deafness-related genetic mutations. Design Clinical study of consecutive newborns in Beijing using allele-specific polymerase chain reaction-based universal array. Study sample This study tested 37 573 newborns within 3 days after birth, including nine sites in four genes: GJB2 (35 del G, 176 del 16, 235 del C, 299 del AT), SLC26A4 (IVS7-2 A > G, 2168 A > G), MTRNR1 (1555 A > G, 1494 C > T), and GJB3 (538 C > T). The birth condition of infants was also recorded. Results Of 37 573 newborns, 1810 carried pathogenic mutations, or 4.817%. The carrier rates of GJB2 (35 del G, 176 del 16, 235 del C, 299 del AT), GJB3 (538 C > T), SLC26A4 (IVS7-2 A > G, 2168 A > G), and MTRNR1 (1555 A > G, 1494 C > T) mutations were 0.005%, 0.104%, 1.924%, 0.551%, 0.295%, 0.253%, 1.387%, 0.024%, and 0.274%, respectively. Logistic regression analysis indicated no statistically significant relationship between mutations and infant sex, premature delivery, twin status, or birth weight. Conclusions The 235delC GJB2 mutation was the most frequent deafness-related mutation in the Chinese population. Genetic screening for the deafness gene will help detect more cases of newborn congenital HL than current screening practices. PMID:26766211

  1. [On the way to Beijing: Dakar Conference].

    PubMed

    Bessis, S

    1994-10-01

    In November 1994 in Senegal, Dakar will host the regional conference on women. Its purpose is to develop a common action plan that Africa will present in Beijing. Nongovernmental organizations (NGOs) and governments have already been preparing for this meeting. This conference had been organized by a series of meetings continent-wide, where governments and NGOs clarified their positions on the 3 themes: equality, development, and peace. The Ministry of Women and the Family has the task of preparing the Senegalese viewpoint of the operation. Senegalese authorities want to make the meeting in Dakar a success. They have decided to have expositions, cultural displays, a women's business forum, a village restaurant where representatives from each country will get to know the culinary wealth of other countries, and a gala event. Everyone is ready to discuss equality, women's access to decision making structures (especially in the education sector), and better distribution of income between the sexes. NGOs do not intend to sit back and do nothing at the conference, but intend to influence the editing of the action plan. Many women's and health-based NGOs are rising up against the gaps of the action plan which only consider women's biological and physical aspects but not their mental and psychological aspects. Participants should consider the disastrous effects of sexual abuse and early marriages. Are governments ready to reform their laws which tend to discriminate against women and institutionalize their low status? Do they have the political will to check the conservative forces, such as those that spoke out against women in the final report of the forum in Tunisia? The number of women in powerful posts in Africa is growing. They can certainly advance things more rapidly than in the recent past. Women at Dakar should work together to address conflicts in Africa. Women should insist that women participate in all peace negotiations. PMID:12179398

  2. Atmospheric mercury monitoring survey in Beijing, China.

    PubMed

    Liu, Shili; Nadim, Farhad; Perkins, Chris; Carley, Robert J; Hoag, George E; Lin, Yuhan; Chen, Letian

    2002-07-01

    With the aid of one industrial, two urban, two suburban, and two rural sampling locations, diurnal patterns of total gaseous mercury (TGM) were monitored in January, February and September of 1998 in Beijing, China. Monitoring was conducted in six (two urban, two suburban, one rural and the industrial sites) of the seven sampling sites during January and February (winter) and in four (two urban, one rural, and the industrial sites) of the sampling locations during September (summer) of 1998. In the three suburban sampling stations, mean TGM concentrations during the winter sampling period were 8.6, 10.7, and 6.2 ng/m3, respectively. In the two urban sampling locations mean TGM concentrations during winter and summer sampling periods were 24.7, 8.3, 10, and 12.7 ng/m3, respectively. In the suburban-industrial and the two rural sampling locations, mean mercury concentrations ranged from 3.1-5.3 ng/m3 in winter to 4.1-7.7 ng/m3 in summer sampling periods. In the Tiananmen Square (urban), and Shijingshan (suburban) sampling locations the mean TGM concentrations during the summer sampling period were higher than winter concentrations, which may have been caused by evaporation of soil-bound mercury in warm periods. Continuous meteorological data were available at one of the suburban sites, which allowed the observation of mercury concentration variations associated with some weather parameters. It was found that there was a moderate negative correlation between the wind speed and the TGM concentration at this suburban sampling location. It was also found that during the sampling period at the same site, the quantity of TGM transported to or from the sampling site was mainly influenced by the duration and frequency of wind occurrence from certain directions. PMID:12137064

  3. Case 3. Administrative Ruling: "Liu Yanwen v. Degree Evaluation Committee of Beijing University"

    ERIC Educational Resources Information Center

    Chinese Education and Society, 2006

    2006-01-01

    This article presents the decision of the First Intermediate People's Court of Beijing regarding the Liu Yanwen v. Degree Evaluation Committee of Beijing University case. The appellant Liu Yanwen was denied a doctoral degree and thus, he sued Beijing University. He disagreed with an earlier ruling made by the People's Court in Haiding District,…

  4. The Post-Junior High School Education of Migrant Children in Beijing

    ERIC Educational Resources Information Center

    Yang, Dongping; Wang, Qi

    2013-01-01

    Attention is being paid to the problem of migrant children in Beijing accessing education after junior high school. Because Beijing students generally do not want a vocational education, the availability of such education in Beijing is shrinking. But a survey indicates a high demand and desire among the children of migrant workers for a vocational…

  5. In-use vehicle emissions in China: Beijing study

    SciTech Connect

    Oliver, Hongyan H.; Gallagher, Kelly Sims ); Li, Mengliang; Qin, Kongjian; Zhang, Jianwei ); Liu, Huan; He, Kebin )

    2009-05-01

    China's economic boom in the last three decades has spurred increasing demand for transportation services and personal mobility. Consequently, vehicle population has grown rapidly since the early 1990s, especially in megacities such as Beijing, Guangzhou, and Tianjin. As a result, mobile sources have become more conspicuous contributors to urban air pollution in Chinese cities. Tianjin was our first focus city, and the study there took us about two years to complete. Building upon the experience and partnership generated through the Tianjin study, the research team carried out the Beijing study from fall 2007–fall 2008. Beijing was chosen to be our second focus city for several reasons: it has the largest local fleet and the highest percentage of the population owning vehicles among all Chinese cities, and it has suffered from severe air pollution, partially due to the ever-growing population of on-road vehicles.

  6. Compressed natural gas vehicles motoring towards a green Beijing

    SciTech Connect

    Yang, Ming; Kraft-Oliver, T.; Guo Xiao Yan

    1996-12-31

    This paper first describes the state-of-the-art of compressed natural gas (CNG) technologies and evaluates the market prospects for CNG vehicles in Beijing. An analysis of the natural gas resource supply for fleet vehicles follows. The costs and benefits of establishing natural gas filling stations and promoting the development of vehicle technology are evaluated. The quantity of GHG reduction is calculated. The objective of the paper is to provide information of transfer niche of CNG vehicle and equipment production in Beijing. This paper argues that the development of CNG vehicles is a cost-effective strategy for mitigating both air pollution and GHG.

  7. Validation of the Beijing version of the REM sleep behavior disorder questionnaire (RBDQ-Beijing) in a mainland Chinese cohort.

    PubMed

    Chang, Yi; Gu, Zhuqin; Zhan, Shuqin; Zhang, Hui; Li, Yuan; An, Jing; Ding, Yan; Nie, Xiuhong; Chan, Piu

    2014-01-01

    REM sleep behavior disorder (RBD) is one type of parasomnia characterized by nocturnal complex motor activity associated with dream mentation. Growing evidence has indicated that RBD is a preclinical stage of neurodegenerative diseases. Therefore screening RBD patient is becoming important. The RBD Questionnaire-Hong Kong (RBDQ-HK) is an effective questionnaire to screen RBD patients. However, it is hard to distinguish RBD with the questionnaire from severe OSAS patients, who could mimic some symptoms of RBD patients. Therefore, we made RBDQ-Beijing by adding two screening questions for OSAS into original RBDQ-HK, including habitual loud snoring and witnessed apnea during sleep. To validate and compare these two questionnaires, 224 subjects were enrolled and screened with these questionnaires, and consequently analyzed with video-polysomnography. Receiver-operator characteristics curve analysis was conducted to attain the best cut-off values of the RBDQ-HK and RBDQ-Beijing. For the RBDQ-HK, the sensitivity was 97.1% and the specificity was 83.2%. More than half of misclassified RBD patients were proved to be severe OSAS patients. For the RBDQ-Beijing, the sensitivity was 95.8% and specificity was 94.3%, indicating that our questionnaire is able to distinguish RBD from severe OSAS patients. In conclusion, RBDQ-Beijing is of help to improve the specificity in RBD screening without excluding the patients with RBD combined OSAS. Therefore the RBDQ-Beijing may be a better screening and preliminary diagnostic tool for RBD than the RBDQ-HK. Moreover, the RBDQ-Beijing would be important for early diagnosis of neurodegenerative diseases and for prevention of injuries to the patient or the patient's bed partner. PMID:25169253

  8. The "Beijing Consensus" and the Chinese Model of University Autonomy

    ERIC Educational Resources Information Center

    Zha, Qiang; Hayhoe, Ruth

    2014-01-01

    This paper attempts to address connections between the Chinese model for development or the "Beijing Consensus" and Chinese universities. Chinese universities seem to be caught between serving governmental agendas and pursuing their own goals as an academic community. Up until recently, they had become used to following the lead of the…

  9. Students' Experiences with Popular Music: The Case of Beijing, China

    ERIC Educational Resources Information Center

    Ho, Wai-Chung

    2016-01-01

    Since the 1980s, the establishment of a socialist market economy has quickened the pace of China's economic development; at the same time, increased modernization and globalization have influenced, to varying degrees, the development of music and music education. With reference to 12 secondary schools in Beijing, this empirical study examines…

  10. Spatial and temporal variations in residential housing prices in Beijing

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Lv, Meng; Yin, Zhongdong

    2009-10-01

    During the past 10 years, the real estate industry in Beijing has been manifesting a strongly growing trend. Researching on the distribution of house prices and their tendencies is helpful to grasp and predict the development of the real estate industry and could be used as reference to city planning. 120 records of housing price data in 2005 to 2006 and open prices in 38 developing projects from the first quarter of 2002 to the second quarter of 2008 were used in this study to analyze the spatial and temporal variations of house price with geostatistical methods and nonlinear regression. Results show that there was a very strong autocorrelation among the house prices in Beijing within the range of about 11 km in 2005 to 2006, which can be well fitted with the spherical model. The isogram of the house prices formed a group of homocentric ellipses, with their long axis extending NW-SE, and the house prices decreased from the center to the periphery. The spatial pattern of house prices in Beijing changed obviously from 2003 to 2006. Although both the spatial patterns for the two periods were homocentric ellipses, the shapes of the ellipses and the directions of the axes changed greatly. And there were more imbalances in 2005 to 2006. The house prices in the Huilongguan-Qinghe residential zone, an example of the typical real estate industry in Beijing, kept growing from 2002 to 2008 and could be fitted with exponential growth model.

  11. Deontological Reconceptualization: A Study of Moral Education in Beijing

    ERIC Educational Resources Information Center

    Misco, Thomas

    2011-01-01

    This study explores the enactment and evolution of moral education in Beijing, China. In particular, the author examines the extent to which moral education teachers develop reflective thinking and broach controversial issues within their classrooms. Drawing on interview data from secondary moral education (deyu) teachers, professors who prepare…

  12. Explaining Late Life Urban vs. Rural Health Discrepancies in Beijing

    ERIC Educational Resources Information Center

    Zimmer, Zachary; Kaneda, Toshiko; Tang, Zhe; Fang, Xianghua

    2010-01-01

    Social characteristics that differ by place of residence are consequential for health. To study implications of this among older adults in rural vs. urban China, this study employs data from the Beijing municipality, a region that has witnessed growth and gaps in development. Life and active life expectancy is assessed using a multistate life…

  13. Education and Identity: The Marginalisation of Migrant Youths in Beijing

    ERIC Educational Resources Information Center

    Kwong, Julia

    2011-01-01

    A person's identity is shaped by one's life experiences. Aside from family, school forms the major backdrop of the everyday experiences of children and plays an important role in shaping identity. This paper examines education and the development of identity among school-age migrant children enrolled in Beijing's schools. Marginality is the theme…

  14. Numeracy of Young Children in Singapore, Beijing and Helsinki

    ERIC Educational Resources Information Center

    Ee, Jessie; Wong, Khoon Yoong; Aunio, Pirjo

    2006-01-01

    Young children's number sense is essential for the acquisition of higher number skills in later years. Most recent studies focus on children over 6 years of age only. To extend the scope, this study dealt with the performance of children aged 4-7 years in 3 cities: Singapore, Beijing and Helsinki (This study is an extension of the research of…

  15. [Evaluation of the ecosystem services of artificial landscapes in Beijing].

    PubMed

    Tian, Gang; Cai, Bo-feng

    2004-09-01

    According to quantitatively evaluating and comparing the ecosystem services of artificial grassland and cultivated trees, artificial pool and constructed wetland in Beijing by the well-accepted method, it was found that the net ecological values of grassland and pool are all negative. It was suggested that cultivated trees are more beneficial than artificial grassland and constructed wetland than artificial pool. PMID:15623013

  16. [Recreational attraction of urban park wetlands in Beijing].

    PubMed

    Li, Fen; Sun, Ran-Hao; Chen, Li-Ding

    2012-08-01

    Taking the 20 urban park wetlands in Beijing as test objects, a 3-layer evaluation index system including urban park wetland landscape quality, location condition, and accessibility for the recreational attraction of urban bark wetlands was established, and, by using analytic hierarchy process (AHP) and an integrating index evaluation method, the recreational attraction of the urban park wetlands in Beijing was quantitatively assessed, and validated with questionnaire data. In Beijing, the urban park wetlands with high recreational attraction were in the order of the Summer Palace, Olympic Park, Qinglong Lake Park, Beihai Park, Yuanmingyuan Park, Yuyuantan Park, Shidu, Golden Sea Lake scenic area, Taoranting Park, and Yeyahu wetland. The Rice Fragrance Lake wetland and Zhenzhuhu scenic area had the lowest recreational attraction, and the others were fair. The evaluation results were supported by the questionnaire data, which indicated that the index system and evaluation model were useful. According to the recreational services, the 20 park wetlands in Beijing could be clustered into four categories, which could be managed in different ways. Appropriately assessing the recreational services of urban park wetlands could help the decision-making on the urban parks optimal planning and designing, improve human living environment, and optimize the spatial distribution of urban landscape. PMID:23189684

  17. Black carbon particles in the urban atmosphere in Beijing

    NASA Astrophysics Data System (ADS)

    Wang, Gengchen; Bai, Jianhui; Kong, Qinxin; Emilenko, Alexander

    2005-09-01

    A study of the concentration of black carbon particles and its variation in the urban atmosphere has been carried out since 1996 in the Beijing area. The measurements were done in the late autumn and early winter each year, the period before and after domestic heating activities begin. The results show the presence of black carbon particles at the high level that vary over a large range in the urban atmosphere in Beijing. The mean value of daily average concentration for the whole observation period of 1996 2004 is 20.0 μg m-3. An evident decrease of black carbon particle concentration in the Beijing area is observed after 2000, and the daily average concentration of black carbon particles is estimated to be 16.0 μg m-3 with a variation range of 2.10 50.50 μg m-3 for the period of 2000 2004. The observation method and main variation behavior characteristics of black carbon particles in the urban atmosphere in the Beijing area are given and discussed.

  18. Beijing: A City in Search of Its Destiny

    ERIC Educational Resources Information Center

    Monk, Liliana B.

    2015-01-01

    This article on the development of Beijing can introduce students to many topics found in the urban geography section of the AP Human Geography course outline published in 2013. The author provides lesson plans and a PowerPoint presentation as resources for teaching a unit about the city.

  19. Source apportionment studies on particulate matter in Beijing/China

    NASA Astrophysics Data System (ADS)

    Suppan, P.; Shen, R.; Shao, L.; Schrader, S.; Schäfer, K.; Norra, S.; Vogel, B.; Cen, K.; Wang, Y.

    2013-05-01

    More than 15 million people in the greater area of Beijing are still suffering from severe air pollution levels caused by sources within the city itself but also from external impacts like severe dust storms and long range advection from the southern and central part of China. Within this context particulate matter (PM) is the major air pollutant in the greater area of Beijing (Garland et al., 2009). PM did not serve only as lead substance for air quality levels and therefore for adverse health impact effects but also for a strong influence on the climate system by changing e.g. the radiative balance. Investigations on emission reductions during the Olympic Summer Games in 2008 have caused a strong reduction on coarser particles (PM10) but not on smaller particles (PM2.5). In order to discriminate the composition of the particulate matter levels, the different behavior of coarser and smaller particles investigations on source attribution, particle characteristics and external impacts on the PM levels of the city of Beijing by measurements and modeling are performed: a) Examples of long term measurements of PM2.5 filter sampling in 2010/2011 with the objectives of detailed chemical (source attribution, carbon fraction, organic speciation and inorganic composition) and isotopic analyses as well as toxicological assessment in cooperation with several institutions (Karlsruhe Institute of Technology (IfGG/IMG), Helmholtz Zentrum München (HMGU), University Rostock (UR), Chinese University of Mining and Technology Beijing, CUMTB) will be discussed. b) The impact of dust storm events on the overall pollution level of particulate matter in the greater area of Beijing is being assessed by the online coupled comprehensive model system COSMO-ART. First results of the dust storm modeling in northern China (2011, April 30th) demonstrates very well the general behavior of the meteorological parameters temperature and humidity as well as a good agreement between modeled and

  20. Multifunctionality assessment of urban agriculture in Beijing City, China.

    PubMed

    Peng, Jian; Liu, Zhicong; Liu, Yanxu; Hu, Xiaoxu; Wang, An

    2015-12-15

    As an important approach to the realization of agricultural sustainable development, multifunctionality has become a hot spot in the field of urban agriculture. Taking 13 agricultural counties of Beijing City as the assessing units, this study selects 10 assessing index from ecological, economic and social aspects, determines the index weight using Analytic Hierarchy Process (AHP) method, and establishes an index system for the integrated agricultural function. Based on standardized data from agricultural census and remote sensing, the integrated function and multifunctionality of urban agriculture in Beijing City are assessed through the index grade mapping. The results show that agricultural counties with the highest score in ecological, economic, and social function are Yanqing, Changping, and Miyun, respectively; and the greatest disparity among those counties is economic function, followed by social and ecological function. Topography and human disturbance may be the factors that affect integrated agricultural function. The integrated agricultural function of Beijing rises at the beginning then drops later with the increase of mean slope, average altitude, and distance from the city. The whole city behaves balance among ecological, economic, and social functions at the macro level, with 8 out of the 13 counties belonging to ecology-society-economy balanced areas, while no county is dominant in only one of the three functions. On the micro scale, however, different counties have their own functional inclination: Miyun, Yanqing, Mentougou, and Fengtai are ecology-society dominant, and Tongzhou is ecology-economy dominant. The agricultural multifunctionality in Beijing City declines from the north to the south, with Pinggu having the most significant agricultural multifunctionality. The results match up well with the objective condition of Beijing's urban agriculture planning, which has proved the methodological rationality of the assessment to a certain extent

  1. [Regional Source Apportionment of PM2.5 in Beijing in January 2013].

    PubMed

    Li, Xuan; Nie, Teng; Qi, Jun; Zhou, Zhen; Sun, Xue-song

    2015-04-01

    In January 2013, Beijing area experienced several severe haze weather events. The pollution of fine particles has become an important problem in Beijing. Understanding the sources of PM2.5 in Beijing is essential for solutions and related policy-formulations. Three-dimensional air quality modelling system was established to analyze the PM2.5 pollution during 20-24 January in 2013. PSAT technology was used to study the regional sources of Beijing PM2.5 pollution. The results showed that local emission was the major source of PM2.5 in Beijing City, with an average contribution rate of 34% . The average contribution rates of Hebei and Tianjin were 26% and 4%, respectively. The neighboring area and the boundary conditions contributed 12% and 24% to PM2.5 in Beijing. In the heavy pollution period, the influence of regional transportation increased significantly, and became the major source of PM2.5 pollution in Beijing. Nitrate in PM2.5 in Beijing mainly came from the surrounding area of Beijing City, while sulfate and secondary organic aerosols showed characteristics of long-distance transportation. Ammonium salt and other components were mainly from Beijing local contribution. PMID:26164884

  2. Cirrus cloud properties measurement using lidar in Beijing

    NASA Astrophysics Data System (ADS)

    Ji, Chengli; Tao, Zongming; Hu, Shunxing; Che, Huizheng; Yu, Jie; Feng, Caiyun; Xie, Chenbo; Liu, Dong; Zhong, Zhiqing; Yuan, Ke'e.; Cao, Kaifa; Huang, Jian; Zhou, Jun; Wang, Yingjian; Chen, Zhenyi

    2016-01-01

    Cirrus cloud has an important effect on the radiation balance between the earth's surface and the atmosphere. The vertical structures, optical depth and effective lidar ratio of cirrus cloud detected by Mie scattering-polarization-Raman lidar system in Beijing from April 11 to December 31, 2012 are analyzed. The results show that the cloud height in Beijing is lower in spring and higher in autumn, with a mean value of about 8km. The mean of cloud thickness is 0.74km. The mean of optical depth is 0.092, and most observed cirrus cloud is thin while optical depth is less than 0.3. The effective lidar ratio of cirrus is lower in summer and higher in winter, inversely related to local temperature, with a mean value of 32.29Sr.

  3. A Survey of Occupational Therapy Practice in Beijing, China.

    PubMed

    Shi, Yun; Howe, Tsu-Hsin

    2016-06-01

    There is an increasing demand for rehabilitation services in China as a result of the growing number of people with physical and mental challenges, as well as the growing population of older adults. The purpose of this study was to explore the current occupational therapy (OT) resources available in Beijing, China, to serve as the first step in planning the response to increasing demand for OT services from the people of China. Specifically, using the snowball sampling survey method, we explored the work practice, including years of working experience, work setting, weekly work hours, annual income and factors related to job satisfaction among occupational therapists in Beijing, China. A total of 44 occupational therapists currently working in the Beijing area responded to our survey. The results demonstrated that most of the therapists working in Beijing area were young and inexperienced. Despite the fact that the participants had an average age of 31 years old and an average of 8 years' working experience, 61.4% of therapists were under 30 years old and more than half of therapists had less than 5 years of OT experiences. Among those included in the study sample, 50% had earned degrees in OT, and the rest of the OT personnel received OT-related on-the-job training in various forms and lengths of time. A majority of the participants worked in hospital settings with adults or children with physical disabilities and used therapeutic activities and therapeutic exercises. Being an occupational therapist is not a high-paying job. Education satisfaction, work experience and annual income are the factors related to job satisfaction for the participants. The majority of occupational therapists expressed the need to receive more support for clinical-related trainings. We plan to expand this pilot study nationwide to gain an in-depth and comprehensive understanding of the OT workforce in China. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26765795

  4. Dynamic changes of sandy land in northwest of Beijing, China.

    PubMed

    Wang, Jing; He, Ting; Guo, Xudong; Liu, Aixia; Zhou, Qing

    2006-10-01

    The area northwest of Beijing is one of the most important regions where many organizations invest and pay most attention. The environmental problems in this region affect not only Beijing but also the surrounding area. Based on observation of the characteristics of the change in sandy land, this study classified four types of dynamic change of sandy land, including extended sandy land, the reversely changed sandy land, the potential sandy land and no change in sandy land. Then the process and the trend of changes in sandy land and their environmental impact on the area northwest of Beijing were analyzed. The results show that the area of sandy land has increased in this region in the period of 1991 to 2002. Change between sandy land and grassland was the dominant change. It is found that the monitoring zones of Hunshandake sandy land and north of Yin Shan are regions with high ratio of extended sandy land, and are connected with widespread potential change of sandy land. This implies that these two regions have a high probability of increase in sandy land in the future. On the other hand, in the monitoring zone of Horqin sandy land and Ba Shang Plateau and its surrounding area, desertification had been controlled and the area of sandy land is expected to decrease. This indicates that the direction of the sandstorm to Beijing is expected to gradually move to the northwest. Furthermore, the decreases in sandy land and the reversing change from arable land to grassland and forests in the study region will affect the land quality and atmosphere. And the logistic multiple regression (LMR) model was employed to better understand the complexity and processes of increases in sandy land. This model predicts that there is a high probability of increases in sandy land in north of Siziwang Banner, Zhengxiangbai Banner and Zhenglan Banner. Finally, suggestions to the ecological construction of the study area have been proposed. PMID:16758285

  5. Atmospheric Particulate Matter Pollution during the 2008 Beijing Olympics

    PubMed Central

    WANG, WENTAO; PRIMBS, TOBY; TAO, SHU; ZHU, TONG; SIMONICH, STACI L. MASSEY

    2009-01-01

    Size fractionated particulate matter (PM) samples (including PM2.5 and PM10) were collected at Peking University in Northwestern Beijing, China for a 2 week period prior to the Olympics, during the 2 week period of the Olympics, and for a 4 week period following the 2008 Olympics, during both source control and non-source control period. PM10 concentrations in this study were high correlated with, but a factor of 1.3 times higher than, the Beijing Environmental Protection Bureau's PM10 concentrations at near-by sites because of differences in the measurement methods used. The mean PM2.5 and PM10 concentrations were statistically different, and lower by 31 and 35%, during the Olympic period compared to the non-Olympic period. However, the PM concentrations were not statistically different between the source control and non-source control periods. While meteorological parameters (air masses from the south and precipitation) accounted for 40% of the total variation in PM10 concentration, source control accounted for 16%, suggesting that meteorology accounted for more of the variation in PM concentration than source control measures. The PM10 concentrations in Beijing during the Olympic period were 2.9, 3.5, and 1.9 times higher than those in Atlanta, Sydney and Athens. In addition, the PM2.5 and PM10 concentrations during the Olympic period exceeded the WHO 24-hour guideline 100% and 81% of the time, respectively. Finally, the PM10 concentrations in October, November, and December 2008 were reduced by 9% to 27% compared to the same months in 2007, suggesting that the Olympic source control efforts (and possibly a down turn in the economy) have resulted in lower PM10 concentrations in Beijing. PMID:19708359

  6. Mycobacterium tuberculosis Beijing Genotype Is Associated with HIV Infection in Mozambique

    PubMed Central

    Viegas, Sofia O.; Machado, Adelina; Groenheit, Ramona; Ghebremichael, Solomon; Pennhag, Alexandra; Gudo, Paula S.; Cuna, Zaina; Langa, Egídio; Miotto, Paolo; Cirillo, Daniela M.; Rastogi, Nalin; Warren, Rob M.; van Helden, Paul D.; Koivula, Tuija; Källenius, Gunilla

    2013-01-01

    The Beijing genotype is a lineage of Mycobacterium tuberculosis that is distributed worldwide and responsible for large epidemics, associated with multidrug-resistance. However, its distribution in Africa is less understood due to the lack of data. Our aim was to investigate the prevalence and possible transmission of Beijing strains in Mozambique by a multivariate analysis of genotypic, geographic and demographic data. A total of 543 M. tuberculosis isolates from Mozambique were spoligotyped. Of these, 33 were of the Beijing lineage. The genetic relationship between the Beijing isolates were studied by identification of genomic deletions within some Regions of Difference (RD), Restriction Fragment Length Polymorphism (RFLP) and Mycobacterial Interspersed Repetivie Unit – variable number tandem repeat (MIRU-VNTR). Beijing strains from South Africa, representing different sublineages were included as reference strains. The association between Beijing genotype, Human Immunodeficiency Virus (HIV) serology and baseline demographic data was investigated. HIV positive serostatus was significantly (p=0.023) more common in patients with Beijing strains than in patients with non-Beijing strains in a multivariable analysis adjusted for age, sex and province (14 (10.9%) of the 129 HIV positive patients had Beijing strains while 6/141 (4.3%) of HIV negative patients had Beijing strains). The majority of Beijing strains were found in the Southern region of Mozambique, particularly in Maputo City (17%). Only one Beijing strain was drug resistant (multi-drug resistant). By combined use of RD and spoligotyping, three genetic sublineages could be tentatively identified where a distinct group of four isolates had deletion of RD150, a signature of the “sublineage 7” recently emerging in South Africa. The same group was very similar to South African “sublineage 7” by RFLP and MIRU-VNTR, suggesting that this sublineage could have been recently introduced in Mozambique from

  7. Environmental degradation and health risks in Beijing, China.

    PubMed

    Qi, Jun; Yang, Linsheng; Wang, Wuyi

    2007-01-01

    As China's capital city, Beijing is experiencing unprecedented environmental degradation accompanied by complex interactions between urbanization and global environmental change, which places human health at risk on a large spatial and temporal scale. For sustainable development that supports environmental and human health in Beijing and during the upcoming "green" Olympic games in 2008, experts and political leaders must acknowledge the urgent health risks from environmental changes related to urbanization. A range of urban health hazards and associated health risks in Beijing result from a variety of factors including heat islands, air pollution, water crisis, soil pollution, infectious diseases, and urban consumerism; in addition, some hazardous health conditions are associated with inequality in living and working conditions. The authors suggest 2 main areas for policy action and research direction: (1) the need to get full-scale information related to environmental monitoring data and health data (and then to provide new methodological approaches and techniques to implement interventions) and (2) the need for effective cooperation among different sectors. PMID:18171645

  8. Land subsidence in Beijing, China, 1955-2010

    NASA Astrophysics Data System (ADS)

    Gu, Z.; Gong, H.; Zhang, Y.; Lu, X.; Liu, H.

    2014-12-01

    Long-term over-exploitation of groundwater since the middle of 1950's and heavy exploitation of surface water in emergency water source since 2001 has caused severe infrastructure destruction and incalculable economic losses in Beijing plain area of China. The maximum of subsidence could reach 1233mm over 60 years. Subsidence integrated monitoring system in this study, based on interferometric synthetic aperture radar (InSAR), leveling network, multilevel monitoring wells and extensometer borehole, was applied to qualitative and quantitative the occurrence, development and evolution of subsidence, which will be helpful to characterize the mechanism of subsidence and predict the future subsidence trend. The monitored results showed subsidence was distributed through most parts of the plain area and formed a broad plain-wide bowl for the period 1955-2010. The maximum accumulated subsidence of five primary localized subsidence bowls-northwest, north, central, south, southwest bowl- recognized in the plain were 700 mm, 1233 mm, 1058 mm, 961 mm, 1030 mm, respectively. Range of subsidence area has expanded outward from urban area to suburban area. The subsidence rates of these subsidence bowls are between 10 mm/yr to 60 mm/yr. Most records show the subsidence rates for the period of 2000-1010 is faster than that of 1955-2000, which indicates land subsidence in Beijing plain area of China has been undergoing rapid development at present. Keywords Land Subsidence • Beijing • Groundwater • InSAR • Mechanism

  9. "APEC Blue": Secondary Aerosol Reductions from Emission Controls in Beijing.

    PubMed

    Sun, Yele; Wang, Zifa; Wild, Oliver; Xu, Weiqi; Chen, Chen; Fu, Pingqing; Du, Wei; Zhou, Libo; Zhang, Qi; Han, Tingting; Wang, Qingqing; Pan, Xiaole; Zheng, Haitao; Li, Jie; Guo, Xiaofeng; Liu, Jianguo; Worsnop, Douglas R

    2016-01-01

    China implemented strict emission control measures in Beijing and surrounding regions to ensure good air quality during the 2014 Asia-Pacific Economic Cooperation (APEC) summit. We conducted synchronous aerosol particle measurements with two aerosol mass spectrometers at different heights on a meteorological tower in urban Beijing to investigate the variations in particulate composition, sources and size distributions in response to emission controls. Our results show consistently large reductions in secondary inorganic aerosol (SIA) of 61-67% and 51-57%, and in secondary organic aerosol (SOA) of 55% and 37%, at 260 m and ground level, respectively, during the APEC summit. These changes were mainly caused by large reductions in accumulation mode particles and by suppression of the growth of SIA and SOA by a factor of 2-3, which led to blue sky days during APEC commonly referred to as "APEC Blue". We propose a conceptual framework for the evolution of primary and secondary species and highlight the importance of regional atmospheric transport in the formation of severe pollution episodes in Beijing. Our results indicate that reducing the precursors of secondary aerosol over regional scales is crucial and effective in suppressing the formation of secondary particulates and mitigating PM pollution. PMID:26891104

  10. Temporal trends of polychlorinated biphenyls in precipitation in Beijing, China

    NASA Astrophysics Data System (ADS)

    Yang, Guosheng; Ma, Lingling; Xu, Diandou; Liu, Liyan; Jia, Hongliang; Chen, Yang; Zhang, Yongbao; Chai, Zhifang

    2012-09-01

    Temporal trend of polychlorinated biphenyls (PCBs) was determined in precipitation and monthly depositional fluxes were calculated in Beijing for the first time from February 2009 to March 2011. Total PCBs concentrations ranged from 7.00 to 993 ng L-1 in dissolved phase and from 1.00 to 133 ng L-1 in particulate phase, with a two orders of magnitude variation. Concentrations of PCBs were dominated by dissolved phase, which accounted for 82.5% of the total PCBs in precipitation, implying PCBs enrichment in rainwater due to efficient scavenging of highly contaminated gas phase and nonfilterable submicron particles which easily adsorbed organic contaminants in urban atmosphere. Highest concentrations of PCBs were measured in snow, which were about two times higher than those in rainwater, demonstrating more efficient scavenging of PCBs by snow. The sum of bi-, tri- and tetrachlorinated congeners accounted for 70.5% of total PCBs in precipitation, suggesting that PCBs mainly come from the historical usage of domestic PCB product, e.g., trichlorobiphenyl. PCBs concentrations in both dissolved and particulate phases showed slow rate of decline, with a half-life of 16.9 years in precipitation, suggesting that the atmospheric concentrations of PCBs were decreasing slowly in Beijing. The wet deposition flux of ∑PCBs ranged from 0.240 to 6.55 μg m-2 month-1 (mean: 1.41 μg m-2 month-1), indicating a relatively high level of PCBs contamination in Beijing atmosphere.

  11. Airborne endotoxin in fine particulate matter in Beijing

    NASA Astrophysics Data System (ADS)

    Guan, Tianjia; Yao, Maosheng; Wang, Junxia; Fang, Yanhua; Hu, Songhe; Wang, Yan; Dutta, Anindita; Yang, Junnan; Wu, Yusheng; Hu, Min; Zhu, Tong

    2014-11-01

    Endotoxin is an important biological component of particulate matter (PM) which, upon inhalation, can induce adverse health effects, and also possibly complicate the diseases in combination with other pollutants. From 1 March 2012 to 27 February 2013 we collected air samples using quartz filters daily for the quantification of airborne endotoxin and also fine PM (PM2.5) in Beijing, China. The geometric means for endotoxin concentration and the fraction of endotoxin in PM were 0.65 EU/m3 (range: 0.10-75.02) and 10.25 EU/mg PM2.5 (range: 0.38-1627.29), respectively. The endotoxin concentrations were shown to vary greatly with seasons, typically with high values in the spring and winter seasons. Temperature and relative humidity, as well as concentrations of sulfur dioxide and nitrogen oxides were found to be significantly correlated with airborne endotoxin concentrations (p < 0.05). Additionally, positive correlations were also detected between endotoxin concentrations and natural sources of Na+, K+, Mg2+, and F-, while negative correlations were observed between endotoxin concentrations and anthropogenic sources of P, Co, Zn, As, and Tl. Oxidative potential analysis revealed that endotoxin concentrations were positively correlated with reactive oxygen species (ROS), but not dithiothreitol (DTT) of PM. This study provided the first continuous time series of airborne endotoxin concentrations in Beijing, and identifies its potential associations with atmospheric factors. The information developed here can assist in the assessment of health effects of air pollution in Beijing.

  12. [Regional eco-security assessment of southwest Beijing].

    PubMed

    Kang, Xiang-Wu; Liu, Xue-Hua; Zhang, Shuang; Ma, Xin

    2007-12-01

    Based on the zoning regulation which integrated climate, vegetation and soil as a complex, a regional eco-security index system consisting of regional physical background, ecosystem stability, landscape structure, and external interference was established, and, with the support of geographical information system technology and fuzzy mathematics, a set of regional eco-security assessment methods was constructed. By means of these methods, the eco-security index of southwest Beijing in 2004 was calculated based on the recent 30 years background data of climate and soil. The results showed that in southwest Beijing, the eco-security degree was higher in its central area and western hilly-shallow hilly areas, but lower in its southern and southeastern plain areas. The mining activity in southwest Beijing had threatened the environment, and should be stopped immediately to maintain the regional eco-security. It was proved in the case study that the assessment index system and related methods established in this paper could solve the existing problems in assessing regional eco-security, and the assessment results could reflect the regional ecological issues and the status of eco-security at different locations within the region. PMID:18333465

  13. [Temporal and spatial distribution characteristics of ozone in Beijing].

    PubMed

    Wang, Zhan-shan; Li, Yun-ting; Chen, Tian; Zhang, Da-wei; Sun, Feng; Sun, Rui-wen; Dong, Xin; Sun, Nai-di; Pan, Li-bo

    2014-12-01

    Ozone concentrations obtained from 35 automatic air monitoring stations in Beijing were analyzed to investigate their temporal and spatial distribution characteristics. A process with high ozone concentration in summer was analyzed. The results showed that ozone maintained relatively high concentration from May to August while in other months, the ozone concentration was at a low level. Overall, the average concentrations of ozone in different stations in a descending order were comparison and regional station, suburban environment evaluation station, urban environmental assessment station and traffic pollution monitoring station. Ozone diurnal variation showed a single peak distribution, the peak of which appeared at 15:00 or 16:00. Ozone concentration showed obvious weekend effect, which meant ozone concentration in daytime of weekend was higher than that in weekday. Ozone concentration was lower in urban Beijing, higher in surrounding counties and the highest in northeast area with more vegetation. A high ozone concentration process occurred in Beijing on June 3, 2013. Under the effect of southwest wind in the afternoon, the concentration peaks of ozone in Yufa, Fengtaihuayuan, Olympic center and Huairou station occurred in order from south to north. Concentration peak of ozone in Huairou station occurred at 20:00 in the night. It could be concluded that significant ozone transmission characteristic was reflected in this process. PMID:25826912

  14. Assessment and forecast of Beijing and Shanghai's urban ecosystem health.

    PubMed

    Li, Yongfa; Li, Dong

    2014-07-15

    In this paper, we first analyze the 5 most cited papers with the title containing "Urban ecosystem health" in Chinese academic journals, and 5 newer papers retrieved from the CSSCI (Chinese Social Sciences Citation Index). The results show that the number of indicators to be used together in more than three papers is 28, and then we select 27 of them to assess Beijing and Shanghai's urban ecosystem health from 2000 to 2011. Secondly, when we standardize the original data, the worst value adjustment coefficient is introduced innovatively. Thirdly, using the entropy method, the weights of concrete indicators of Beijing and Shanghai in the different adjustment coefficients are calculated respectively. Fourthly, based on the fuzzy matter-element method, using the Hamming approach degree, the two cities' ecosystem health index and the contribution value to overall health index from each component are calculated. Lastly, using gray prediction model, the evolutionary time response sequence function of Beijing and Shanghai's urban ecosystem health index is identified, and thus both cities' urban ecosystem health is predicted. PMID:24784740

  15. Composition, distribution, and characterization of polybrominated diphenyl ethers in sandstorm depositions in Beijing, China.

    PubMed

    Fu, S; Yang, Z Z; Zhang, L; Li, K; Xu, X B

    2009-08-01

    This study was conducted to determine the concentration of 8 polybrominated diphenyl ethers (PBDEs) in sandstorm depositions in Beijing, China. The PBDE concentrations in 10 samples collected in Beijing ranged from 8.47 to 29.02 ng g(-1), with BDE-209 as the predominant congener (>85%). Principal component analysis revealed that the major source of PBDEs in Beijing may be potentially associated with deca-BDE. Furthermore, increasing PBDE contamination was observed from northwest to east Beijing. Finally, possible factors affecting contamination of the sandstorm depositions were subsequently explored revealing a significant correlation between SigmaPBDEs and the minimum particle size of the sandstorm deposition samples. PMID:19322505

  16. Southern East Asian origin and coexpansion of Mycobacterium tuberculosis Beijing family with Han Chinese.

    PubMed

    Luo, Tao; Comas, Iñaki; Luo, Dan; Lu, Bing; Wu, Jie; Wei, Lanhai; Yang, Chongguang; Liu, Qingyun; Gan, Mingyu; Sun, Gang; Shen, Xin; Liu, Feiying; Gagneux, Sebastien; Mei, Jian; Lan, Rushu; Wan, Kanglin; Gao, Qian

    2015-06-30

    The Beijing family is the most successful genotype of Mycobacterium tuberculosis and responsible for more than a quarter of the global tuberculosis epidemic. As the predominant genotype in East Asia, the Beijing family has been emerging in various areas of the world and is often associated with disease outbreaks and antibiotic resistance. Revealing the origin and historical dissemination of this strain family is important for understanding its current global success. Here we characterized the global diversity of this family based on whole-genome sequences of 358 Beijing strains. We show that the Beijing strains endemic in East Asia are genetically diverse, whereas the globally emerging strains mostly belong to a more homogenous subtype known as "modern" Beijing. Phylogeographic and coalescent analyses indicate that the Beijing family most likely emerged around 30,000 y ago in southern East Asia, and accompanied the early colonization by modern humans in this area. By combining the genomic data and genotyping result of 1,793 strains from across China, we found the "modern" Beijing sublineage experienced massive expansions in northern China during the Neolithic era and subsequently spread to other regions following the migration of Han Chinese. Our results support a parallel evolution of the Beijing family and modern humans in East Asia. The dominance of the "modern" Beijing sublineage in East Asia and its recent global emergence are most likely driven by its hypervirulence, which might reflect adaption to increased human population densities linked to the agricultural transition in northern China. PMID:26080405

  17. BUDEM: an urban growth simulation model using CA for Beijing metropolitan area

    NASA Astrophysics Data System (ADS)

    Long, Ying; Shen, Zhenjiang; Du, Liqun; Mao, Qizhi; Gao, Zhanping

    2008-10-01

    It is in great need of identifying the future urban form of Beijing, which faces challenges of rapid growth in urban development projects implemented in Beijing. We develop Beijing Urban Developing Model (BUDEM in short) to support urban planning and corresponding policies evaluation. BUDEM is the spatio-temporal dynamic model for simulating urban growth in Beijing metropolitan area, using cellular automata (CA) and Multi-agent system (MAS) approaches. In this phase, the computer simulation using CA in Beijing metropolitan area is conducted, which attempts to provide a premise of urban activities including different kinds of urban development projects for industrial plants, shopping facilities, houses. In the paper, concept model of BUDEM is introduced, which is established basing on prevalent urban growth theories. The method integrating logistic regression and MonoLoop is used to retrieve weights in the transition rule by MCE. After model sensibility analysis, we apply BUDEM into three aspects of urban planning practices: (1) Identifying urban growth mechanism in various historical phases since 1986; (2) Identifying urban growth policies needed to implement desired urban form (BEIJING2020), namely planned urban form; (3) Simulating urban growth scenarios of 2049 (BEIJING2049) basing on the urban form and parameter set of BEIJING2020.

  18. A Comparative Study of Child Temperament and Parenting in Beijing, China and the Western United States

    ERIC Educational Resources Information Center

    Porter, Christian L.; Hart, Craig H.; Yang, Chongming; Robinson, Clyde C.; Olsen, Susanne Frost; Zeng, Qing; Olsen, Joseph A.; Jin, Shenghua

    2005-01-01

    The purpose of this investigation was to examine comparable dimensions and linkages between child temperament and parenting styles with samples from Beijing, China and the western United States. Participants included 404 mothers and fathers from Beijing, China and 325 mothers and fathers from the western United States. Both mothers and fathers…

  19. Residents' Perceived Social-Economic Impact of the 2008 Beijing Olympic Games

    ERIC Educational Resources Information Center

    Zhang, Mark; Chen, Li; Lei, Ouyang; Malone, Christopher

    2013-01-01

    This study was designed to examine whether the Olympic Games was a catalyst for changes to Beijing residents' quality of life based on social-economic perspectives and how these changes affected their continuous support for the Games. Residents who lived in Beijing 18 months or longer were invited to participate in this survey research (N =…

  20. School-Based Primary School Sexuality Education for Migrant Children in Beijing, China

    ERIC Educational Resources Information Center

    Liu, Wenli; Su, Yufen

    2014-01-01

    In May 2007, Beijing Normal University launched a programme of school-based sexuality education for migrant children in Xingzhi Primary School in Beijing. Over the past seven years, the project team has developed a school-based sexuality education curriculum using the "International Technical Guidance on Sexuality Education" published by…

  1. Case 2. Administrative Ruling: "Liu Yanwen v. Degree Evaluation Committee of Beijing University"

    ERIC Educational Resources Information Center

    Chinese Education and Society, 2006

    2006-01-01

    This article describes in detail the Liu Yanwen v. Degree Evaluation Committee of Beijing University case. The plaintiff Liu Yanwen sued the Degree Evaluation Committee of Beijing University for its disapproval of his doctoral degree. In 1996, although his doctoral thesis titled "An Ultra-Short Laser Pulse Driven High Current Density Photoelectric…

  2. Portrayals of Pro-Beijing Workers' Night Schools in Hong Kong from 1946 to Post-1997

    ERIC Educational Resources Information Center

    Lau, Chui Shan

    2011-01-01

    This study focuses on the transformation of pro-Beijing labour education in the socio-political context of Hong Kong. It explores the reasons that Hong Kong pro-Beijing educators initiated Workers' Night Schools for adults; the organisation of schools in many locales and the transformation of labour education that workers received in these…

  3. Chemical and sulfur isotopic composition of precipitation in Beijing, China.

    PubMed

    Zhu, Guangxu; Guo, Qingjun; Chen, Tongbin; Lang, Yunchao; Peters, Marc; Tian, Liyan; Zhang, Hanzhi; Wang, Chunyu

    2016-03-01

    China is experiencing serious acid rain contamination, with Beijing among the worst-hit areas. To understand the chemical feature and the origin of inorganic ions in precipitation of Beijing, 128 precipitation samples were collected and analyzed for major water-soluble ions and δ(34)S. The pH values ranged from 3.68 to 7.81 and showed a volume weighted average value (VWA) of 5.02, with a frequency of acid rain of 26.8 %. The VWA value of electrical conductivity (EC) was 68.6 μS/cm, which was nearly 4 times higher than the background value of northern China. Ca(2+) represented the main cation; SO4 (2-) and NO3 (-) were the dominant anion in precipitation. Our study showed that SO4 (2-) and NO3 (-) originated from coal and fossil fuel combustion; Ca(2+), Mg(2+), and K(+) were from the continental sources. The δ(34)S value of SO4 (2-) in precipitation ranged from +2.1 to +12.8‰ with an average value of +4.7‰. The δ(34)S value showed a winter maximum and a summer minimum tendency, which was mainly associated with temperature-dependent isotope equilibrium fractionation as well as combustion of coal with relatively positive δ(34)S values in winter. Moreover, the δ(34)S values revealed that atmospheric sulfur in Beijing are mainly correlated to coal burning and traffic emission; coal combustion constituted a significant fraction of the SO4 (2-) in winter precipitation. PMID:26573310

  4. Prediction of vibrations induced by underground railway traffic in Beijing

    NASA Astrophysics Data System (ADS)

    Gupta, S.; Liu, W. F.; Degrande, G.; Lombaert, G.; Liu, W. N.

    2008-02-01

    This paper examines the problem of subway induced vibrations on line 4 of Beijing metro, which is currently under construction and is planned to pass in close proximity of the Physics Laboratory of Beijing University. The laboratory has a lot of equipment that is very sensitive to traffic induced vibrations and future operation of metro line 4 is a matter of concern. Hence, it is important to study the influence of subway induced vibrations inside the laboratory and to propose a viable solution to mitigate the vibrations. In this paper, the tunnel north of Chengfulu station is modelled using a coupled periodic FE-BE model and the free-field response due to moving trains is predicted. In addition, vibration measurements have been performed on the site of the Physics Laboratory to estimate the existing vibration levels due to road traffic. The predicted and measured vibrations are superimposed to assess the vibrations due to the combined effect of road and railway traffic in the vicinity of the Physics Laboratory. Apart from the numerical investigations, vibration measurements have also been performed on a similar site at line 1 of Beijing metro to substantiate the estimated results on metro line 4. Finally, it is studied how the vibrations can be controlled using a floating slab track, which is widely used as an effective measure of vibration isolation in tunnels. The efficiency of a 7.9 Hz floating slab track as a vibration countermeasure is assessed in this paper. This study demonstrates the applicability of the numerical model for the relevant assessment of subway induced vibrations and its use to study the performance of different track structures in the tunnel.

  5. Radioxenon monitoring in Beijing following the Fukushima Daiichi NPP accident.

    PubMed

    Shilian, Wang; Qi, Li; Qinghua, Meng; Zhanying, Chen; Yungang, Zhao; Huijuan, Li; Huaimao, Jia; Yinzhong, Chang; Shujiang, Liu; Xinjun, Zhang; Yuanqing, Fan; Ling, Wan; Yun, Lou

    2013-11-01

    This paper reports the brief process and results of radioxenon monitoring and analysis in Beijing following the Fukushima Daiichi nuclear power plant accident. The accident and release of volatile radionuclides were caused by 9.0 magnitude earthquake and tsunami on March 11, 2011. The maximum concentrations of (133)Xe and (131 m)Xe were in excess of 0.90 Bq.m(-3) and 0.047 Bq.m(-3), respectively. The activity ratio of (131 m)Xe to (133)Xe and the dynamic trend of (133)Xe activity concentration were analyzed. PMID:23601858

  6. Evidence of Aerosol's Influence on Climate from Beijing Olympics

    NASA Astrophysics Data System (ADS)

    Chen, S.; Fu, Q.; Huang, J.; Ge, J.; Su, J.

    2009-12-01

    Air pollution is a difficult problem during the process of industrialization in most developing countries. In China, the main air pollutants are inhaled aerosol particles. Because of the extremely high loading and rapid development, Beijing became a heavily polluted city, with a population of more than 16 million. The 2008 Olympic Summer Games provided a unique opportunity for the study of climate effects of aerosols due to many measurements taken to fight pollution caused by industrialization and economic growth.Surface temperature is the most intuitive meteorological factor and easy to get. Therefore, aerosol’s radiative effects on regional climate can be known by studying the relationship between aerosols and surface temperature in Beijing city in August 2008. However, many factors can affect the surface temperature and cloud is considered as a very important meteorological element in radiation balance. In order to remove the impact of clouds on surface temperature, here the ground temperature in clear sky days (when cloud cover is less than 2) are selected. Aerosol data from the MODerate resolution Imaging Spectroradiometer (MODIS) onboard the Earth Observing System (EOS) Aqua shows that aerosol concentration decreased significantly in the area of Olympic venues in August 2008. Meanwhile, the ground-based observation data shows the surface temperature during the day (14LT) and night (02LT) in August 2008 is higher and lower than the mean temperature in August from 2002 to 2008, respectively. It is discovered that the distribution of satellite-retrieved aerosol optical Depth (AOD) in the whole area of Beijing in August of 2003 and 2004 is similar to that in 2008. We chosen four meteorological stations to analyze surface temperature and found that the diurnal changes of surface temperature are consistent with that in August of 2003, 2004 and 2008. Meanwhile, the decrease of AOD in the area of Olympic venues in August 2008 leads to the increase of precipitation

  7. Compositions and pollutant sources of haze in Beijing urban sites.

    PubMed

    Wang, Junmei; Song, Yujun; Zuo, Jiangnan; Wu, Hongwen

    2016-05-01

    Haze from urban sites in Beijing was collected with a self-assembled electrostatic dust collector. The sizes and morphologies, thermal properties, and compositions of the particles in the haze were characterized by scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and X-ray photoelectric spectroscopy (XPS), respectively. Based on these results, the causes and pollutant sources of the chemicals in the haze were analyzed, and some countermeasures were further advanced to reduce the related pollutant sources. Graphical abstract ᅟ. PMID:26810665

  8. Differential MicroRNA Expression in Human Macrophages with Mycobacterium tuberculosis Infection of Beijing/W and Non-Beijing/W Strain Types

    PubMed Central

    Zheng, Lin; Leung, Eric; Lee, Nelson; Lui, Grace; To, Ka-Fai; Chan, Raphael C. Y.; Ip, Margaret

    2015-01-01

    Objectives The role of microRNAs in association with Mycobacterium tuberculosis (MTB) infection and the immunology regulated by microRNAs upon MTB infection have not been fully unravelled. We examined the microRNA profiles of THP-1 macrophages upon the MTB infection of Beijing/W and non-Beijing/W clinical strains. We also studied the microRNA profiles of the host macrophages by microarray in a small cohort with active MTB disease, latent infection (LTBI), and from healthy controls. Results The results revealed that 14 microRNAs differentiated infections of Beijing/W from non-Beijing/W strains (P<0.05). A unique signature of 11 microRNAs in human macrophages was identified to differentiate active MTB disease from LTBI and healthy controls. Pathway analyses of these differentially expressed miRNAs suggest that the immune-regulatory interactions involving TGF-β signalling pathway take part in the dysregulation of critical TB processes in the macrophages, resulting in active expression of both cell communication and signalling transduction systems. Conclusion We showed for the first time that the Beijing/W TB strains repressed a number of miRNAs expressions which may reflect their virulence characteristics in altering the host response. The unique signatures of 11 microRNAs may deserve further evaluation as candidates for biomarkers in the diagnosis of MTB and Beijing/W infections. PMID:26053546

  9. Quality of Life in Cancer Patients with Pain in Beijing

    PubMed Central

    Yang, Ping; Sun, Li-qiu; Pang, Dong

    2012-01-01

    Objective To investigate the quality of life (QOL) of cancer pain patients in Beijing, and explore the effect of cancer pain control on patients’ QOL. Methods Self-developed demographic questionnaire, numeric rating scale and SF-36 questionnaire were used together among 643 cancer pain patients in 28 Grade 2nd to 3rd general hospitals and 2 Grade 3rd cancer hospitals. Results The SF-36 eight dimensions scores ranged from 31.75 to 57.22 in these cancer pain patients. The t test and Wilcoxon rank sum test were used to compare the QOL between pain controlled (PC) group and pain uncontrolled (PUC) group, and the results showed that patients in PC group had the higher QOL scores in 6 areas of SF-36 (P<0.05). Binary logistic regression results found that pain management satisfaction scores (P<0.001), family average personal monthly income (P=0.029), current receiving chemotherapy (P=0.009) and cancer stage (P<0.001) were the predictors to cancer pain controlled results. Conclusion Cancer patients with pain in Beijing had poor QOL. Pain control will improve the QOL of cancer pain patients. PMID:23359351

  10. [Characteristics of atmospheric nitrogen wet deposition in Beijing urban area].

    PubMed

    He, Cheng-Wu; Ren, Yu-Fen; Wang, Xiao-Ke; Mao, Yu-Xiang

    2014-02-01

    With the ion-exchange resin method, the atmospheric nitrogen wet deposition in Beijing urban area within the Fifth Ring Road was investigated from June to October, 2012. The relationship between atmospheric nitrogen wet deposition and rainfall precipitation was investigated, the differences of nitrogen wet deposition in different months, different ring roads (the Fifth Ring Road, the Fourth Ring Road, the Third Ring Road and the Second Ring Road) and different functional areas (institutes and colleges district, ring-road, residential areas, railway station and public garden) were also investigated. The results showed that the average value and standard deviation of ammonia-nitrogen, nitrate-nitrogen and nitrite-nitrogen were significantly different during different months in 2012. The atmospheric nitrite nitrogen deposition first decreased and then increased, the maximum value appeared in September. The positive relationships between ammonia nitrogen (nitrate nitrogen) and mean monthly precipitation and negative relationships between nitrite nitrogen and mean monthly precipitation were both significant (P < 0.05). The three nitrogen depositions of ring-road and railway station were higher than other functional areas, but only the nitrite nitrogen deposition had obvious regional difference. The differences of the three nitrogen depositions among different ring roads were all not significant and it meant that the nitrogen wet deposition was equally distributed in Beijing urban area. PMID:24812938

  11. Obstacles to women's progress to be addressed in Beijing.

    PubMed

    Seufert-barr, N

    1995-03-01

    Speakers at the Third Social, Humanitarian, and Cultural Committee Assembly held in December 1994 maintained that power sharing between women and men is still intolerably low and that economic hardship, abuse, and discrimination remain. One speaker announced that society needs to do more to challenge obstacles to women's advancement: poverty, violence, access to resources, women's rights, education, and health. She asserted that, for this reason, the Fourth World Conference on Women scheduled for September 1995 in Beijing must succeed. Discussions and action at the December assembly will constitute a major part of the groundwork for the Beijing Conference. The Committee debate centered on the advancement of women as a cause and effect of development. The 1994 World Survey on the Role of Women in Development shows that economic development may be complexly connected with advancement of women. In societies where women have progressed, the economy tends to grow steadily, while, in societies where women cannot fully participate in development, the economy is stagnant. The Assembly called on the Commission on the Status of Women to ensure that the Platform for Action recognize and incorporate older women's concerns and contributions to development into its strategies, programs, and policies. It also called for countries to protect women migrant workers from violence and corrupt recruitment practices. It condemned the illegal trafficking of women and girls across borders for sexual or economic oppressive and exploitative purposes and for other illegal activities (forced domestic labor, false marriages, clandestine employment, and false adoption). PMID:12346144

  12. Characteristics of 2-methyltetrols in ambient aerosol in Beijing, China

    NASA Astrophysics Data System (ADS)

    Liang, Linlin; Engling, Guenter; Duan, Fengkui; Cheng, Yuan; He, Kebin

    2012-11-01

    PM10 and PM2.5 samples were collected from November, 2010 to October, 2011 at Tsinghua University in Beijing. Various carbohydrates were quantified by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), including the 2-methyltetrols (2-methylthreitol and 2-methylerythritol). A clear seasonal variation in the ambient 2-methyltetrol concentrations was observed, with the highest levels occurring in the summer, followed by autumn, spring and winter. The average concentrations of the 2-methyltetrols in PM10 and PM2.5 were 17.5 ± 15.4 ng m-3 and 13.8 ± 12.2 ng m-3, respectively. The 2-methyltetrols exhibited significant positive correlations with ambient relative humidity and temperature, likely due to the higher isoprene emission strength and enhanced formation yield under higher temperature and humidity conditions. In contrast, there was no relationship between the concentration of 2-methyltetrols and sunshine duration. The significant positive correlation (R2 = 0.76) between 2-methyltetrols and SO42- indicated that high concentrations of SO42- can increase the formation rate of 2-methyltetrols from isoprene. Moreover, 2-methyltetrols were also observed in the winter time in Beijing, illustrating the enhancement of the 2-methyltetrol formation rate by high concentrations of pollutants in ambient aerosol.

  13. [Public awareness assessment of water reuse in Beijing].

    PubMed

    Zhang, Wei-Ling; Chen, Wei-Ping; Jiao, Wen-Tao

    2012-12-01

    Reusing reclaimed municipal wastewater to mitigate urban water shortage is gaining widespread attentions. Beijing has led the nation in implementation and close to 60% of the treated municipal wastewater effluent is being reused. We evaluated the public's awareness of water reuse practices throughout the city. Based on questionnaire and the SPSS software, we analyzed the people's knowledge on water, wastewater and reclaimed issues and willingness to use reclaimed water along with their socio-economical background. While the public was keenly aware of the severe water shortage and the need to treat wastewater, they did not have clear ideas on sources of water supply, the biggest users of water, and the largest contributor of municipal wastewater. Results show that the majority of the Beijing residents we surveyed were not cognizant of water reuses taken places throughout the city. Greater than 80% of the residents would accept reclaimed wastewater for reuses even for domestic usages as long as not related to drinking and food preparation. However, 63% of them would reject reusing it to supplement the public water supply. In general, subjects at a higher education level, with higher personal income, and between ages of 35 to 55 tended to be more supportive of the water reuses. The gender did not significantly affect the outcome of the survey. To enhance the awareness of the city residents, it suggests forwarding the propaganda and management, strengthening the policy-oriented and facility support from the public, community and government. PMID:23379134

  14. Improving urban air quality in China: Beijing case study

    SciTech Connect

    Jiming Hao; Litao Wang

    2005-09-01

    China is undergoing rapid urbanization because of unprecedented economic growth. As a result, many cities suffer from air pollution. Two-thirds of China's cities have not attained the ambient air quality standards applicable to urban residential areas (Grade II). Particulate matter (PM), rather than sulfur dioxide (SO{sub 2}), is the major pollutant reflecting the shift from coal burning to mixed source pollution. In 2002, 63.2 and 22.4% of the monitored cities have PM and SO{sub 2} concentrations exceeding the Grade II standard, respectively. Nitrogen oxides (NOx) concentration kept a relatively stable level near the Grade II standard in the last decade and had an increasing potential in recent years because of the rapid motorization. In general, the air pollutants emission did not increase as quickly as the economic growth and energy consumption, and air quality in Chinese cities has improved to some extent. Beijing, a typical representative of rapidly developing cities, is an example to illustrate the possible options for urban air pollution control. Beijing's case provides hope that the challenges associated with improving air quality can be met during a period of explosive development and motorization. 21 refs., 19 figs., 6 tabs.

  15. Temporal variations of organochlorine pesticides in precipitation in Beijing, China

    NASA Astrophysics Data System (ADS)

    Yang, Guosheng; Ma, Lingling; Xu, Diandou; Liu, Liyan; Jia, Hongliang; Chen, Yang; Zhang, Yongbao; Chai, Zhifang

    2012-12-01

    Temporal variations of organochlorine pesticides (OCPs) were determined in precipitation and monthly depositional fluxes were calculated in Beijing from February 2009 to March 2011. Compounds which were detected most often included α-HCH and β-HCH, and the volume-weighted mean (VWM) concentration of hexachlorocyclohexanes (HCHs) was 33.0 ng L-1, accounting for 72.3% of the ∑OCPs in precipitation. The total concentrations of OCPs ranged from 3.73 to 152 ng L-1 (mean: 29.7 ± 3.5 ng L-1) for dissolved phase and from 1.61 to 114 ng L-1 (mean: 15.9 ± 2.0 ng L-1) for particulate phase, respectively. OCPs in dissolved phase dominated sampled concentrations in precipitation (HCHs: 71.8%, Chlordane: 77.7%, dichlorodiphenyltrichloroethanes-DDTs: 50.1%) with an exception of hexachlorobenzene-HCB (26.3%). Furthermore, the distribution coefficient, Kpd, was generally large in low temperature, especially in spring. The abundance of ∑OCPs in the precipitation fluctuated monthly, with high value in late winter and spring. The past farmland near the sampling site was under construction during sampling, which may be an important local re-emission source in this study. The elevated wet deposition flux of 11 selected OCPs was 14.9 μg m-2 yr-1 in Beijing.

  16. New Particle Formation and Secondary Organic Aerosol in Beijing

    NASA Astrophysics Data System (ADS)

    Hu, M.; Yue, D.; Guo, S.; Hu, W.; Huang, X.; He, L.; Wiedensohler, A.; Zheng, J.; Zhang, R.

    2011-12-01

    Air pollution in Beijing has been a major concern due to being a mega-city and green Olympic Games requirements. Both long term and intensive field measurements have been conducted at an Urban Air Quality Monitoring Station in the campus of Peking University since 2004. Aerosol characteristics vary seasonally depending on meteorological conditions and source emissions. Secondary compositions of SNA (sum of sulfate, nitrate, and ammonium) and SOA (secondary organic aerosol) become major fraction of fine particles, which may enhance aerosol impacts on visibility and climate change. The transformation processes of new particle formation (NPF) and secondary organic aerosol have been focused on. It was found that gaseous sulfuric acid, ammonia, and organic compounds are important precursors to NPF events in Beijing and H2SO4-NH3-H2O ternary nucleation is one of the important mechanisms. The contributions of condensation and neutralization of sulfuric acid, coagulation, and organics to the growth of the new particles are estimated as 45%, 34%, and 21%, respectively. Tracer-based method to estimate biogenic and anthropogenic SOA was established by using gas chromatography-mass spectrometry. Secondary organic tracers derived from biogenic (isoprene, α-pinene, β-caryophyllene) and anthropogenic (toluene) contributed 32% at urban site and 35% at rural site, respectively. Other source apportionment techniques were also used to estimate secondary organic aerosols, including EC tracer method, water soluble organic carbon content, chemical mass balance model, and AMS-PMF method.

  17. A novel method for the rapid and prospective identification of Beijing Mycobacterium tuberculosis strains by high-resolution melting analysis.

    PubMed

    Alonso, M; Navarro, Y; Barletta, F; Martínez Lirola, M; Gotuzzo, E; Bouza, E; García de Viedma, D

    2011-03-01

    Genotypic analysis of Mycobacterium tuberculosis (MTB) has enabled the definition of several lineages. The Beijing family, which is considered highly virulent and transmissible, has been associated with resistance in certain settings and involved in severe outbreaks, making it one of the most closely-monitored lineages. Therefore, rapid prospective identification of Beijing MTB strains could be relevant. In the present study, we evaluate a real-time PCR followed by high-resolution melting (HRM) based on the identification of a single nucleotide polymorphism (SNP) in the Rv2629 gene which defines Beijing lineage (A191C for Beijing genotype and A191A for non-Beijing genotype). This combined methodology efficiently differentiated Beijing and non-Beijing strains in 100% of the isolates from a collection of reference strains without requiring specific DNA probes. Additionally, HRM was able to assign a Beijing/non-Beijing genotype in 90.9% of the respiratory specimens assayed. Its applicability was tested on a Peruvian sample of circulating MTB strains, in which it identified 10.7% as belonging to the Beijing genotype; this proportion reached 20% in the North Lima area. HRM analysis of the A191C SNP is a rapid, reliable, and sensitive method for the efficient prospective survey of high-risk Beijing MTB strains, even in developing settings where MTB culture is often not available. PMID:20384709

  18. Proteome analysis of the Mycobacterium tuberculosis Beijing B0/W148 cluster

    PubMed Central

    Bespyatykh, Julia; Shitikov, Egor; Butenko, Ivan; Altukhov, Ilya; Alexeev, Dmitry; Mokrousov, Igor; Dogonadze, Marine; Zhuravlev, Viacheslav; Yablonsky, Peter; Ilina, Elena; Govorun, Vadim

    2016-01-01

    Beijing B0/W148, a “successful” clone of Mycobacterium tuberculosis, is widespread in the Russian Federation and some countries of the former Soviet Union. Here, we used label-free gel-LC-MS/MS shotgun proteomics to discover features of Beijing B0/W148 strains that could explain their success. Qualitative and quantitative proteome analyses of Beijing B0/W148 strains allowed us to identify 1,868 proteins, including 266 that were differentially abundant compared with the control strain H37Rv. To predict the biological effects of the observed differences in protein abundances, we performed Gene Ontology analysis together with analysis of protein-DNA interactions using a gene regulatory network. Our results demonstrate that Beijing B0/W148 strains have increased levels of enzymes responsible for long-chain fatty acid biosynthesis, along with a coincident decrease in the abundance of proteins responsible for their degradation. Together with high levels of HsaA (Rv3570c) protein, involved in steroid degradation, these findings provide a possible explanation for the increased transmissibility of Beijing B0/W148 strains and their survival in host macrophages. Among other, we confirmed a very low level of the SseA (Rv3283) protein in Beijing B0/W148 characteristic for all «modern» Beijing strains, which could lead to increased DNA oxidative damage, accumulation of mutations, and potentially facilitate the development of drug resistance. PMID:27356881

  19. Genetic diversity of the Mycobacterium tuberculosis Beijing family based on multiple genotyping profiles.

    PubMed

    Liu, Y; Wang, S; Lu, H; Chen, W; Wang, W

    2016-06-01

    Among the most prevalent Mycobacterium tuberculosis (Mtb) strains worldwide is the Beijing genotype, which has caused large outbreaks of tuberculosis (TB). Characteristics facilitating the dissemination of Beijing family strains remain unknown, but they are presumed to have been acquired through evolution of the lineage. To explore the genetic diversity of the Beijing family Mtb and explore the discriminatory ability of mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) loci in several regions of East Asia, a cross-sectional study was conducted with a total of 163 Beijing strains collected from registered TB patients between 1 June 2009 and 31 November 2010 in Funing County, China. The isolated strains were analysed by 15-MIRU-VNTR loci typing and compared with published MIRU-VNTR profiles of Beijing strains. Synonymous single nucleotide polymorphisms at 10 chromosomal positions were also analysed. The combination of SNP and MIRU-VNTR typing may be used to assess Mtb genotypes in areas dominated by Beijing strains. The modern subfamily in Shanghai overlapped with strains from other countries, whereas the ancient subfamily was genetically differentiated across several countries. Modern subfamilies, especially ST10, were prevalent. Qub11b and four other loci (MIRU 26, Mtub21, Qub26, Mtub04) could be used to discriminate Beijing strains. PMID:26667080

  20. Emission Controls Versus Meteorological Conditions in Determining Aerosol Concentrations in Beijing during the 2008 Olympic Games

    SciTech Connect

    Gao, Yi; Liu, Xiaohong; Zhao, Chun; Zhang, Meigen

    2011-12-12

    A series of emission control measures were undertaken in Beijing and the adjacent provinces in China during the 2008 Beijing Olympic Games on August 8th-24th, 2008. This provides a unique opportunity for investigating the effectiveness of emission controls on air pollution in Beijing. We conducted a series of numerical experiments over East Asia for the period of July to September 2008 using a coupled meteorology-chemistry model (WRF-Chem). Model can generally reproduce the observed variation of aerosol concentrations. Consistent with observations, modeled concentrations of aerosol species (sulfate, nitrate, ammonium, black carbon, organic carbon, total particulate matter) in Beijing were decreased by 30-50% during the Olympic period compared to the other periods in July and August in 2008 and the same period in 2007. Model results indicate that emission controls were effective in reducing the aerosol concentrations by comparing simulations with and without emission controls. However, our analysis suggests that meteorological conditions (e.g., wind direction and precipitation) are at least as important as emission controls in producing the low aerosol concentrations appearing during the Olympic period. Transport from the regions surrounding Beijing determines the temporal variation of aerosol concentrations in Beijing. Based on the budget analysis, we suggest that emission control strategy should focus on the regional scale instead of the local scale to improve the air quality over Beijing.

  1. Emission controls versus meteorological conditions in determining aerosol concentrations in Beijing during the 2008 Olympic Games

    NASA Astrophysics Data System (ADS)

    Gao, Y.; Liu, X.; Zhao, C.; Zhang, M.

    2011-12-01

    A series of emission control measures were undertaken in Beijing and the adjacent provinces in China during the 2008 Beijing Olympic Games on 8-24 August 2008. This provides a unique opportunity for investigating the effectiveness of emission controls on air pollution in Beijing. We conducted a series of numerical experiments over East Asia for the period of July to September 2008 using a coupled meteorology-chemistry model (WRF-Chem). Model can generally reproduce the observed variation of aerosol concentrations. Consistent with observations, modeled concentrations of aerosol species (sulfate, nitrate, ammonium, black carbon, organic carbon, total particulate matter) in Beijing were decreased by 30-50% during the Olympic period compared to the other periods in July and August in 2008 and the same period in 2007. Model results indicate that emission controls were effective in reducing the aerosol concentrations by comparing simulations with and without emission controls. In addition to emission controls, our analysis suggests that meteorological conditions (e.g. wind direction and precipitation) were also important in producing the low aerosol concentrations appearing during the Olympic period. Transport from the regions surrounding Beijing determined the daily variation of aerosol concentrations in Beijing. Based on the budget analysis, we suggest that to improve the air quality over Beijing, emission control strategy should focus on the regional scale instead of the local scale.

  2. Understanding temporal patterns and characteristics of air quality in Beijing: A local and regional perspective

    NASA Astrophysics Data System (ADS)

    Chen, Ziyue; Xu, Bing; Cai, Jun; Gao, Bingbo

    2016-02-01

    Sources, characteristics and seasonal variation of airborne pollutants in China, especially in Beijing, have been massively examined. However, most studies analyze local air quality from an isolated perspective and interactions between local and regional air quality have not been fully considered. This research attempts to evaluate Beijing air quality at the local and regional scale. The weighted cross correlogram spectral matching (CCSM) and convergent cross mapping (CCM) method are employed for similarity and causality analysis respectively. At the local scale, the air quality in Beijing experiences frequent and sudden change, yet changes smoothly across a day's time. At the regional scale, the air quality in Beijing and four neighboring cities is compared. The result suggests that although air quality in Beijing and neighboring cities is of some differences, strong bidirectional coupling exists between the local and regional air quality. The research indicates that air quality in Beijing is better than the general situation in this region, and Tianjin should be a good comparative site for monitoring and evaluating air quality in Beijing. This research provides a feasible methodology for comprehensive analysis of local air quality at multiple scales, which may shed some lights on the forthcoming implementation of local air quality evaluation.

  3. Proteome analysis of the Mycobacterium tuberculosis Beijing B0/W148 cluster.

    PubMed

    Bespyatykh, Julia; Shitikov, Egor; Butenko, Ivan; Altukhov, Ilya; Alexeev, Dmitry; Mokrousov, Igor; Dogonadze, Marine; Zhuravlev, Viacheslav; Yablonsky, Peter; Ilina, Elena; Govorun, Vadim

    2016-01-01

    Beijing B0/W148, a "successful" clone of Mycobacterium tuberculosis, is widespread in the Russian Federation and some countries of the former Soviet Union. Here, we used label-free gel-LC-MS/MS shotgun proteomics to discover features of Beijing B0/W148 strains that could explain their success. Qualitative and quantitative proteome analyses of Beijing B0/W148 strains allowed us to identify 1,868 proteins, including 266 that were differentially abundant compared with the control strain H37Rv. To predict the biological effects of the observed differences in protein abundances, we performed Gene Ontology analysis together with analysis of protein-DNA interactions using a gene regulatory network. Our results demonstrate that Beijing B0/W148 strains have increased levels of enzymes responsible for long-chain fatty acid biosynthesis, along with a coincident decrease in the abundance of proteins responsible for their degradation. Together with high levels of HsaA (Rv3570c) protein, involved in steroid degradation, these findings provide a possible explanation for the increased transmissibility of Beijing B0/W148 strains and their survival in host macrophages. Among other, we confirmed a very low level of the SseA (Rv3283) protein in Beijing B0/W148 characteristic for all «modern» Beijing strains, which could lead to increased DNA oxidative damage, accumulation of mutations, and potentially facilitate the development of drug resistance. PMID:27356881

  4. Evaluating the environmental quality impact of the 2008 Beijing Olympic Games: magnetic monitoring of street dust in Beijing Olympic Park

    NASA Astrophysics Data System (ADS)

    Qiao, Qingqing; Zhang, Chunxia; Huang, Baochun; Piper, John D. A.

    2011-12-01

    Aggressive traffic intervention and emission control measures implemented during the 2008 Olympic Games in Beijing created a valuable case study for evaluating the effectiveness of measures for mitigating environmental pollution and protecting public health. Results are reported here for a suite of magnetic and non-magnetic (microscopic, chemical and statistical) methods conducted on street dust deposits and parkland soils around the Olympic Park in Beijing. In both areas magnetic grains with multidomain properties predominate; grain sizes are coarser in the heavy traffic regions and finer in the park areas with evidence for particulate steel dust input in the former case. Traffic is the major source of anthropogenic magnetic particle-induced enhancement of magnetic susceptibility in street dust; however, domestic combustion processes (mainly coal burning) are found to contribute a significant magnetic signature in the urban environment during the winter. Due to the traffic intervention, magnetic compositions in street dust decreases significantly during the Olympic Games. Correlations between magnetic parameters and heavy metal contents prove that magnetic parameters can be used as proxies for heavy metal pollution.

  5. Southern East Asian origin and coexpansion of Mycobacterium tuberculosis Beijing family with Han Chinese

    PubMed Central

    Luo, Tao; Comas, Iñaki; Luo, Dan; Lu, Bing; Wu, Jie; Wei, Lanhai; Yang, Chongguang; Liu, Qingyun; Gan, Mingyu; Sun, Gang; Shen, Xin; Liu, Feiying; Gagneux, Sebastien; Mei, Jian; Lan, Rushu; Wan, Kanglin; Gao, Qian

    2015-01-01

    The Beijing family is the most successful genotype of Mycobacterium tuberculosis and responsible for more than a quarter of the global tuberculosis epidemic. As the predominant genotype in East Asia, the Beijing family has been emerging in various areas of the world and is often associated with disease outbreaks and antibiotic resistance. Revealing the origin and historical dissemination of this strain family is important for understanding its current global success. Here we characterized the global diversity of this family based on whole-genome sequences of 358 Beijing strains. We show that the Beijing strains endemic in East Asia are genetically diverse, whereas the globally emerging strains mostly belong to a more homogenous subtype known as “modern” Beijing. Phylogeographic and coalescent analyses indicate that the Beijing family most likely emerged around 30,000 y ago in southern East Asia, and accompanied the early colonization by modern humans in this area. By combining the genomic data and genotyping result of 1,793 strains from across China, we found the “modern” Beijing sublineage experienced massive expansions in northern China during the Neolithic era and subsequently spread to other regions following the migration of Han Chinese. Our results support a parallel evolution of the Beijing family and modern humans in East Asia. The dominance of the “modern” Beijing sublineage in East Asia and its recent global emergence are most likely driven by its hypervirulence, which might reflect adaption to increased human population densities linked to the agricultural transition in northern China. PMID:26080405

  6. Characterizations of atmospheric fungal aerosol in Beijing, China

    NASA Astrophysics Data System (ADS)

    Liang, Linlin; Engling, Guenter; He, Kebin; Du, Zhenyu

    2013-04-01

    Fungal aerosols constitute the most abundant fraction of biological aerosols in the atmosphere, influencing human health, the biosphere, atmospheric chemistry and climate. However, the total abundance of fungal spores in the atmosphere is still poorly understood and quantified. PM10 and PM2.5 samples were collected by high volume samplers simultaneously at a rural site (MY) and an urban site (THU) in Beijing, China. Various carbohydrates were quantified by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), including the sugar alcohols mannitol and arabitol, proposed as molecular tracers for fungal aerosol. The annual average concentrations of arabitol in PM2.5 and PM10 at the THU site were 7.4±9.4 ng/m3 and 10.3±9.5 ng/m3, and the respective mannitol concentrations were 21.0±20.4 ng/m3 and 31.9±26.9 ng/m3. Compared to PM10, the monthly average concentrations of arabitol and mannitol in PM2.5 did not vary significantly and were present at nearly consistent levels in the different seasons. Moreover, during summer and autumn higher arabitol and mannitol levels than during spring and winter were observed in coarse particles, probably due to different dominant sources of fungal spores in different seasons. In the dry period (i.e., winter and spring) in Beijing, probably only the suspension from exposed surfaces, (e.g., soil resuspension, transported dust, etc.) can be regarded as the main sources for fungal aerosols. On the other hand, in summer and autumn, fungal spores in the atmosphere can be derived from more complex sources, including plants, vegetation decomposition and agricultural activity, such as ploughing; these fungal spore sources may contribute more to coarse PM. Mannitol and arabitol correlated well with each other, both in PM10 (R2 = 0.71) and PM2.5 (R2 = 0.81). Although fungal spore levels at rural sites were consistently higher than those at urban sites in other studies, the findings in our study were

  7. Observation of atmospheric nitrous acid with DOAS in Beijing, China.

    PubMed

    Qin, Min; Xie, Pin-Hua; Liu, Wen-Qing; Li, Ang; Dou, Ke; Fang, Wu; Liu, Jian-Guo; Zhang, Wei-Jun

    2006-01-01

    Measurements of nitrous acid (HONO) and nitrogen dioxide (NO2) in Beijing City have been performed by means of a developed differential optical absorption spectroscopy (DOAS) system based on photodiode array (PDA), during the autumn of 2004. HONO and NO2 were simultaneously identified by their characteristic absorption bands in the spectral region between 337 nm and 372 nm with high sensibility and time resolution. The concentrations of HONO exhibit obviously diurnal variation with a nocturnal maximum and a daytime minimum. The highest HONO value up to 11.8 microg/m3 was observed during the night of 2/3 September. Possible sources of the observed HONO were discussed. Good correlation to NO2 indicates that NO2 is a main source component. The measurement also shows direct emission of HONO is an important source in strongly polluted urban area. PMID:20050551

  8. [Characteristics and Parameterization for Atmospheric Extinction Coefficient in Beijing].

    PubMed

    Chen, Yi-na; Zhao, Pu-sheng; He, Di; Dong, Fan; Zhao, Xiu-juan; Zhang, Xiao-ling

    2015-10-01

    In order to study the characteristics of atmospheric extinction coefficient in Beijing, systematic measurements had been carried out for atmospheric visibility, PM2.5 concentration, scattering coefficient, black carbon, reactive gases, and meteorological parameters from 2013 to 2014. Based on these data, we compared some published fitting schemes of aerosol light scattering enhancement factor [ f(RH)], and discussed the characteristics and the key influence factors for atmospheric extinction coefficient. Then a set of parameterization models of atmospheric extinction coefficient for different seasons and different polluted levels had been established. The results showed that aerosol scattering accounted for more than 94% of total light extinction. In the summer and autumn, the aerosol hygroscopic growth caused by high relative humidity had increased the aerosol scattering coefficient by 70 to 80 percent. The parameterization models could reflect the influencing mechanism of aerosol and relative humidity upon ambient light extinction, and describe the seasonal variations of aerosol light extinction ability. PMID:26841588

  9. A vertical subsurface-flow constructed wetland in Beijing

    NASA Astrophysics Data System (ADS)

    Chen, Z. M.; Chen, B.; Zhou, J. B.; Li, Z.; Zhou, Y.; Xi, X. R.; Lin, C.; Chen, G. Q.

    2008-11-01

    Presented in this paper is an integrated cost and efficiency analysis of a pilot vertical subsurface-flow constructed wetland (CW) built up in 2004 near the Longdao River in Beijing, China. The CW has been monitored over one year and proved to be a good solution to treat the polluted water and restored the ecosystem health of the Longdao River. The modified CW system in accordance with local conditions costs less in construction, operation and maintenance than traditional wastewater treatment system and occupies less land than conventional CW. Also, derived from the efficiency analysis, the Longdao River CW provides better elimination effects for nutrient substances in the polluted river water and has stable performances in cold seasons.

  10. Seasonal variations of atmospheric heterocyclic aromatic amines in Beijing, China

    NASA Astrophysics Data System (ADS)

    Dong, Xueling; Liu, Dameng; Gao, Shaopeng

    2013-02-01

    Heterocyclic aromatic amines (HAAs) belong to a group of substances associated with a high mutagenic and carcinogenic potential. This study reports that carcinogenic HAAs may be present in airborne particles. Airborne particles (PM10) were sampled from March 2005 to January 2006 at four urban sites in Beijing. Collected particulate matter was analyzed for six HAAs using high-performance liquid chromatography (HPLC) with fluorescence and UV detection. Clear seasonal variations of HAAs were observed with seasonal mass concentrations ranging from 0.66 ± 0.20 ng m- 3 (summer) to 19.76 ± 14.38 ng m- 3 (autumn). The carcinogenic amino-imidazo-azaarenes, including 2-Amino-3-methyl-3H-imidazo[4,5-f] quinoline (IQ), 2-Amino-3,4-dimethyl-3H-imidazo[4,5-f] quinoline (MeIQ), and 2-Amino-1-methyl-6-phenylimidazo[4,5-b] pyridine (PhIP), were the major components with 75.2-87.0% of the total HAAs during the whole year except for summer. 3-Amino-1-methyl-5H-pyrido[3,4-b] indole (Trp-P-2), 2-Amino-9H-pyrido[2,3-b] indole (AαC), and 2-Amino-3-methyl-9H-pyrido[2,3-b] indole (MeAαC), with similar structures, were found to have similar seasonal patterns and strong correlations (r = 0.63-0.90) throughout the observation, which indicates that they most likely come from similar emission sources. Positive correlations between site-specific HAA concentrations and the relative humidity were observed. Of the different sites studied, the total HAA concentrations were most abundant at commercial sites and the smallest at residential sites. The combustion aerosols emitted from cooking, coal, and petroleum may be the sources of these carcinogens in the atmosphere, and cooking emissions may probably play an important role in Beijing's HAAs pollution.

  11. Beijing bids to "repair house before it rains".

    PubMed

    1995-12-18

    This article describes AIDS conditions in Beijing, China. It is feared that the world's most populous country may experience AIDS in epidemic proportions. HIV infections are spreading due to increased prostitution and drug use. Official figures estimate 2428 HIV positive cases and 77 persons in advanced stages of AIDS since 1985. 66% of cases were among IV drug users, 16% were among foreigners, and 10% were Chinese migrants who returned from abroad. 530 new cases were reported in 1994, and 654 were reported for the first six months of 1995. Reported cases included only those people required to have HIV testing. Some government experts report an estimated 100,000 HIV infected persons. At the international AIDS conference in Japan in 1994, one expert reported that AIDS infections were mostly among IV drug users in Yunnan province, which is just over the border from Burma's supply of heroin and opium. AIDS prevention efforts in China are hampered by individual disinterest and propriety. Education should be aimed at young people and high-risk groups. The State Education Commission recently introduced its college level AIDS prevention program among 80,000 students in Shanghai and Henan province in September 1995. The program involved dissemination of leaflets about AIDS prevention and control and lectures. Progress is being made toward development of a school text about AIDS and toward establishment of a training center in Beijing. The World Health Organization has opened six AIDS prevention training classes in seven provinces. Misinformation about the means of transmission and treatment is considered common. The China Youth Daily newspaper reports that 20% of men and 10% of women have had premarital sex. The China Sexology Research Center reports that 18% of male and 17% of female college students have had premarital sexual relations. 70% of students nationwide are considered to have had premarital sexual experience. PMID:12291188

  12. [Air Quality Characteristics in Beijing During Spring Festival in 2015].

    PubMed

    Cheng, Nian-liang; Chen, Tian; Zhang, Da-wei; Li, Yun-ting; Sun, Feng; Wei, Qiang; Liu, Jia-lin; Liu, Bao-xian; Sun, Rui-wen

    2015-09-01

    To analyze the impacts of emissions from fireworks on the air quality, monitoring data of PM2.5, PM10, SO2, NO2 chemical compositions of PM2.5 of automatic air quality stations in Beijing during Spring Festival(February 18th-24th) in 2015 were investigated. Moreover, we also estimated the fireworks on the New Year's Eve produced based on the ratio of PM.5 to CO. Analysis results showed that the concentrations of PM2.5, PM10, SO2, NO2 during 2015 Spring Festival was 116. 85, 184.71, 22. 14, and 36. 27 µg.m-3 respectively, which raised 52. 61%, 92. 41%, - 40. 15%, - 0.46% respectively compared to the same period in 2014; the concentration peaks of PM2.5, PM10, SO2, NO2 at 1 : 00 am on 19th was 412. 69, 541. 63, 152. 73, 51. 09 µg.m-3, respectively, which was increased 19. 02%, 14. 37%, 76. 57%, 11. 35% compared to that of 2014; the concentration peaks at dense population area were significantly higher than that in other districts; fireworks had great influence on the chemical compositions of PM2.5 especially on the concentrations of chloride ion, potassium ion, magnesian ion, which were 18. 85, 66. 72, and 70. 10 times than that in 2013-2014; fireworks resulted in severe air pollution in a short time and the estimated fireworks on the New Year's Eve was approximately 2. 13 x 10(5) kg of PM2.5. Reduction of pollutants during Spring Festival had a positive significant impact on air quality in Beijing. PMID:26717673

  13. Particulate matter assessment of a wetland in Beijing.

    PubMed

    Qiu, Dongdong; Liu, Jiakai; Zhu, Lijuan; Mo, Lichun; Zhang, Zhenming

    2015-10-01

    To increase the knowledge on the particulate matter of a wetland in Beijing, an experimental study on the concentration and composition of PM10 and PM2.5 was implemented in Beijing Olympic Forest Park from 2013 to 2014. This study analyzed the meteorological factors and deposition fluxes at different heights and in different periods in the wetlands. The results showed that the mean mass concentrations of PM10 and PM2.5 were the highest at 06:00-09:00 and the lowest at 15:00-18:00. And the annual concentration of PM10 and PM2.5 in the wetland followed the order of dry period (winter)>normal water period (spring and autumn)>wet period (summer), with the concentration in the dry period significantly higher than that in the normal water and wet periods. The chemical composition of PM2.5 in the wetlands included NH4(+), K(+), Na(+), Mg(2+), SO4(2-), NO3(-), and Cl(-), which respectively accounted for 12.7%, 1.0%, 0.8%, 0.7%, 46.6%, 33.2%, and 5.1% of the average annual composition. The concentration of PM10 and PM2.5 in the wetlands had a significant positive correlation with relative humidity, a negative correlation with wind speed, and an insignificant negative correlation with temperature and radiation. The daily average dry deposition amount of PM10 in the different periods followed the order of dry period>normal water period>wet period, and the daily average dry deposition amount of PM2.5 in the different periods was dry period>wet period>normal water period. PMID:26456611

  14. The Phenomena of Dropping Out and Criminal Delinquency among Middle and Primary School Students in Beijing.

    ERIC Educational Resources Information Center

    Xianrong, Chen

    1987-01-01

    Reports juvenile crime statistics and dropout rates for primary and middle school students in the Beijing municipality for the years 1978 through 1984. Includes a discussion of the reasons for dropouts and suggestions on how to solve the problem. (JDH)

  15. A modeling analysis of a heavy air pollution episode occurred in Beijing

    NASA Astrophysics Data System (ADS)

    An, X.; Zhu, T.; Wang, Z.; Li, C.; Wang, Y.

    2006-08-01

    Because concentrations of fine particulate matter (PM) and ozone in Beijing often exceed healthful levels, China is to taking steps to improve Beijing's air quality for the 2008 Olympic Games. In this paper the Models-3 Community Multiscale Air Quality (CMAQ) Modeling System was used to investigate a heavy air pollution episode in Beijing during 3-7 April 2005. The modeling domain covered from East Asia with four nested grids with 81 to 3 km horizontal resolution focusing on urban Beijing. This was coupled with a regional emissions inventory with a 10 km resolution and a local 1km Beijing emissions database. The trend of predicted concentrations of various pollutants agreed reasonably well with the observations and captured the main features of this heavy pollution episode. The simulated column concentration distribution of PM was correlated reasonably with the MODIS remote sensing products. Control runs with and without Beijing emissions were conducted to quantify the contributions of non-Beijing sources (NBS) to the Beijing local air pollution. The contributions of NBS to each species differed spatially and temporally with the order of PM25>PM10>SO2>SOIL for this episode. The percentage contribution of NBS to fine particle (PM2.5) in Beijing was averaged about 40%, up to 80% at the northwest of urban Beijing and only 10-20% at southwest. The spatial distribution of NBS contributions for PM10 was similar to that for PM2.5, with a slightly less average percentage of about 30%. The NBS contributions for SO2 and SOIL (diameter between 2.5 μm and 10 μm) were only 10-20% and 5-10%. In addition, the pollutant transport flux was calculated and compared at different levels to investigate transport pathway and magnitude. It was found that the NBS contribution correlated with the transport flux, contributing 70% of PM10 concentration in Beijing at the time of transport flux peak during a strong episode with a transport path from southwest to northeast.

  16. Quantifying the air pollutants emission reduction during the 2008 Olympic games in Beijing.

    PubMed

    Wang, Shuxiao; Zhao, Meng; Xing, Jia; Wu, Ye; Zhou, Yu; Lei, Yu; He, Kebin; Fu, Lixin; Hao, Jiming

    2010-04-01

    Air quality was a vital concern for the Beijing Olympic Games in 2008. To strictly control air pollutant emissions and ensure good air quality for the Games, Beijing municipal government announced an "Air Quality Guarantee Plan for the 29th Olympics in Beijing". In order to evaluate the effectiveness of the guarantee plan, this study analyzed the air pollutant emission reductions during the 29th Olympiad in Beijing. In June 2008, daily emissions of SO(2), NO(X), PM(10), and NMVOC in Beijing were 103.9 t, 428.5 t, 362.7 t, and 890.0 t, respectively. During the Olympic Games, the daily emissions of SO(2), NO(X), PM(10), and NMVOC in Beijing were reduced to 61.6 t, 229.1 t, 164.3 t, and 381.8 t -41%, 47%, 55%, and 57% lower than June 2008 emission levels. Closing facilities producing construction materials reduced the sector's SO(2) emissions by 85%. Emission control measures for mobile sources, including high-emitting vehicle restrictions, government vehicle use controls, and alternate day driving rules for Beijing's 3.3 million private cars, reduced mobile source NO(X) and NMVOC by 46% and 57%, respectively. Prohibitions on building construction reduced the sector's PM(10) emissions by approximately 90% or total PM(10) by 35%. NMVOC reductions came mainly from mobile source and fugitive emission reductions. Based on the emission inventories developed in this study, the CMAQ model was used to simulate Beijing's ambient air quality during the Olympic Games. The model results accurately reflect the environmental monitoring data providing evidence that the emission inventories in this study are reasonably accurate and quantitatively reflect the emission changes attributable to air pollution control measures taken during the 29th Olympic Games in 2008. PMID:20222727

  17. Letters from Augustin Hallerstein, an eighteenth century Jesuit astronomer in Beijing

    NASA Astrophysics Data System (ADS)

    Juznic, Stanislav

    2008-11-01

    Augustin Hallerstein (1703-1774) was the last astronomer sent to Beijing by the Society of Jesus. He left Europe for China in his mid-thirties, and continued to send letters back home until he died thirty-five years later. These letters and reports contained important information on Chinese astronomy, and were read in the courts of Europe; many were also published. Hallerstein was one of the most important European astronomers in Beijing, his European publications surpassing those of his predecessors.

  18. Aerosol optical properties observed during Campaign of Air Quality Research in Beijing 2006 (CAREBeijing-2006): Characteristic differences between the inflow and outflow of Beijing city air

    NASA Astrophysics Data System (ADS)

    Garland, R. M.; Schmid, O.; Nowak, A.; Achtert, P.; Wiedensohler, A.; Gunthe, S. S.; Takegawa, N.; Kita, K.; Kondo, Y.; Hu, M.; Shao, M.; Zeng, L. M.; Zhu, T.; Andreae, M. O.; PöSchl, U.

    2009-01-01

    Ground-based measurements of aerosol optical properties were conducted during Campaign of Air Quality Research in Beijing 2006 (CAREBeijing-2006) (11 August to 9 September 2006) at a suburban site ˜30 km south of Beijing. Averaged over the measurement campaign (arithmetic mean ± standard deviation), the total scattering coefficients (σs) were 469 ± 374 Mm-1 (450 nm), 361 ± 295 Mm-1 (550 nm), and 249 ± 206 Mm-1 (700 nm) and the absorption coefficient (σa) was 51.8 ± 36.5 Mm-1 (532 nm). The average Ångström exponent was 1.42 ± 0.19 (450 nm/700 nm) and the average single scattering albedo (ω532) was 0.86 ± 0.07 (532 nm) with minimum values as low as 0.5. Pronounced diurnal cycles were observed in σs, σa, and ω532 and can be explained by boundary layer mixing effects. Additionally, an enhancement of absorbing particles in the early morning (0500-0800 local time) was observed; this may be attributed to soot emissions from traffic activity. When the measured air masses originated in the north and passed over Beijing, the single scattering albedo was generally low (ω532 < 0.8), which indicates that the local emissions of particulate matter in Beijing were dominated by primary particles from combustion sources (soot). The southerly inflow to Beijing had typically very high σs and higher than average ω532 values, suggesting a large amount of secondary aerosol (e.g., sulfate and oxidized organics). Overall, the results suggest that a majority of the particle pollution in Beijing is transported into the city from the south.

  19. Contribution of regional transport to the black carbon aerosol during winter haze period in Beijing

    NASA Astrophysics Data System (ADS)

    Wang, Qiyuan; Huang, Ru-Jin; Cao, Junji; Tie, Xuexi; Shen, Zhenxing; Zhao, Shuyu; Han, Yongming; Li, Guohui; Li, Zhengqiang; Ni, Haiyan; Zhou, Yaqing; Wang, Meng; Chen, Yang; Su, Xiaoli

    2016-05-01

    The mass concentrations of atmospheric refractory black carbon (rBC), an important absorber of solar radiation, were continuously measured with a single particle soot photometer (SP2) during wintertime haze period to investigate the transport of pollution to Beijing. The average mass concentration of rBC was 6.1 ± 3.9 μg m-3 during hazy periods, which was 4.7 times higher than it during non-hazy periods. Cluster analysis showed that the air parcels arriving at Beijing mainly originated from the northwest, passed through the south and brought the most polluted air to Beijing. Concentration-weighted trajectory analyses indicated that the central North China Plain were the most likely source region for the rBC that impacted Beijing. Furthermore, the Weather Research and Forecasting-Black Carbon model showed that 71.4-82.0% of the rBC at Beijing was from regional transport during the high rBC episodes and that 47.9-56.8% of the rBC can be attributed to sources in the central North China Plain. These results suggest that regional transport from the central North China Plain, rather than local emissions, was a more important source for rBC pollution in Beijing.

  20. Contribution of regional transport to the black carbon aerosol during winter haze period in Beijing

    NASA Astrophysics Data System (ADS)

    Wang, Qiyuan; Huang, Ru-Jin; Cao, Junji; Tie, Xuexi; Shen, Zhenxing; Zhao, Shuyu; Han, Yongming; Li, Guohui; Li, Zhengqiang; Ni, Haiyan; Zhou, Yaqing; Wang, Meng; Chen, Yang; Su, Xiaoli

    2016-05-01

    The mass concentrations of atmospheric refractory black carbon (rBC), an important absorber of solar radiation, were continuously measured with a single particle soot photometer (SP2) during wintertime haze period to investigate the transport of pollution to Beijing. The average mass concentration of rBC was 6.1 ± 3.9 μg m-3 during hazy periods, which was 4.7 times higher than it during non-hazy periods. Cluster analysis showed that the air parcels arriving at Beijing mainly originated from the northwest, passed through the south and brought the most polluted air to Beijing. Concentration-weighted trajectory analyses indicated that the central North China Plain were the most likely source region for the rBC that impacted Beijing. Furthermore, the Weather Research and Forecasting-Black Carbon model showed that 71.4-82.0% of the rBC at Beijing was from regional transport during the high rBC episodes and that 47.9-56.8% of the rBC can be attributed to sources in the central North China Plain. These results suggest that regional transport from the central North China Plain, rather than local emissions, was a more important source for rBC pollution in Beijing.

  1. Studying the pollution of Moscow and Beijing atmospheres with carbon monoxide and aerosol

    NASA Astrophysics Data System (ADS)

    Golitsyn, G. S.; Grechko, E. I.; Wang, Gengchen; Wang, Pucai; Dzhola, A. V.; Emilenko, A. S.; Kopeikin, V. M.; Rakitin, V. S.; Safronov, A. N.; Fokeeva, E. V.

    2015-01-01

    The measurements of submicron aerosol and black carbon (BC) surface concentrations, and carbon monoxide (CO) total column in 1992-2012 in Beijing and Moscow are illustrated. The specific features in the long-term variations in the studied impurities in these megacities are discussed. The level of pollution with all three impurities in Beijing is substantially higher than in Moscow. From 1992 to 1999, the monthly means of black carbon and aerosol increased in Beijing. These concentrations substantially decreased beginning from 2000. From 2007 to 2011, black carbon decreased and submicron aerosol increased. In 1996-2003 the urban part of CO total column (TC) in Beijing was on average higher than in 2006-2012 by a factor of 1.4. The anthropogenic part of CO in Moscow decreased in 2006-2012. High aerosol and CO concentrations, comparable with concentrations rather typical of Beijing, were observed in Moscow only during wildfires in 2010. Using the cluster analysis statistical methods, it has been indicated that the main sources of the air pollution in Beijing are located 100-500 km southward.

  2. Some results of CO and aerosols atmospheric pollution investigations in Moscow and Beijing

    NASA Astrophysics Data System (ADS)

    Rakitin, Vadim; Wang, Gengchen; Wang, Pusai; Grechko, Evgeny; Dzhola, Anatoly; Emilenko, Alexander; Fokeeva, Ekaterina; Kopeikin, Vladimir; Safronov, Alexander

    2014-05-01

    Results of the CO total column (TC) and submicron (sbm) and soot concentrations measurements in Moscow and Beijing for period from 1992 to 2013 years are presented. The rate of decrease of CO TC Moscow anthropogenic portion is 1.4 % per year for 1992-2013 years in spite of multiple increase of the motor vehicles number. There are no significant changes in CO TC over Beijing for whole period of measurements (1992-2013 years). Soot concentration in Beijing has decreased while sbm aerosol has increased since 2006 year. Level of atmospheric CO and aerosols pollution in Beijing is 2-5 times stronger in comparison with Moscow ones. Reasonably typical of atmospheric pollution events for Beijing with extreme values of CO TC and aerosols concentrations were observed in Moscow during wild fires of 2002 and 2010 years only. Trajectory cluster analysis using has allowed studying the location of sources of CO and aerosols emissions. Relatively stronger atmospheric pollution of Beijing partially due to the atmospheric transportation from industry regions of China located to south, south-east and east from the city.

  3. Contributions a L'etude de la Dynamique des Lasers a Modes Synchronises

    NASA Astrophysics Data System (ADS)

    Morin, Michel

    Cette these examine theoriquement deux aspects de la synchronisation des modes d'un laser. D'une part, on etudie l'influence de la desyntonisation de la frequence de modulation sur la stabilite des impulsions produites par la synchronisation modale AM. On montre que la desyntonisation provoque une perte de convergence intrinseque du processus de synchronisation active independante de la presence de bruit dans la cavite. La plage de convergence est d'autant plus etroite que le nombre de modes sous la courbe de gain est eleve. En pratique, elle est considerablement reduite par le bruit present dans la cavite. La synchronisation interferentielle, realisee a l'aide d'une cavite couplee contenant un element non-lineaire, est aussi etudiee. On decrit les principes generaux de la compression resultant de l'interference de deux impulsions. On evalue les performances realisables en fonction du taux de compression et de modulation de phase de l'element non-lineaire. Une etude detaillee du laser a interferometre de Michelson non-lineaire et non dispersif est presentee.

  4. Beijing diary: ten days at the women's conference.

    PubMed

    Craft, N

    1995-10-14

    A British Medical Journal editor recorded her impressions and experiences at the Fourth World Conference on Women in the form of a 10-day diary. She described a logistical nightmare extending from her attempt to check into the hotel where she had a reservation to workshops and meetings held in unfinished buildings, overcrowded classrooms, and public areas of a hotel (even after hotel management extinguished the lights). The journalist's movements were dutifully recorded by a uniformed attendant, and taxi drivers refused to take her to the conference center. Early lobbying and strategy meetings revolved around the issues to be discussed at the conference. The opening of the Conference was marked with pomp and ceremony while workshops held at the nongovernmental (NGO) forum 50 miles away provided an opportunity for women to describe their attempts to improve their status. Rain forced Hilary Clinton to speak inside and disappointed thousands of women who had waited in line for hours to hear her comments. Betty Friedan described the conference as a metaphor for women's experience in the world and called for a "new vision of equality." Debates at the NGO forum centered around the rights of parents to have access to their children's medical records and punitive measures for women who have had abortions. At the Conference, the UN was unable to explain the paucity of women in positions of under secretary general or higher. By the end of the first week, the governments of Australia, India, Tanzania, China, the US, Ghana, the UK, Turkey, and Cambodia had all made commitments to improve the status of women. During the second week of the Conference the wording for the Beijing Declaration and Platform for Action was passed through various committees. The resulting document represents a significant contribution to the gradual progress towards equity for women, instead of a major shift in world view, but grassroots organizations will find in it the ammunition to hold governments

  5. Characteristics of Submicron Aerosols in 2013 summer of Beijing

    NASA Astrophysics Data System (ADS)

    Guo, Song; Hu, Min; Shang, Dongjie; Zheng, Jing; Du, Zhuofei; Wu, Yusheng; Lu, Sihua; Zeng, Limin; Zhang, Renyi

    2016-04-01

    To characterize the air pollution of North China Plain of China, CAREBEIJING-2013 field campaign (Campaigns of Air quality REsearch in BEIJING and surrounding region) was conducted in summer of 2013. Submicron aerosols were measured at an urban site PKU (Peking University, 39° 59'21"N, 116° 18'25"E) from July 28th to September 31st 2013. A suite of integrated instruments was used to measure the size distribution, effective density and hygroscopicity of ambient particles. The chemical composition of submicron particles were measured by using an Aerodyne High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) (Billerica, MA, USA). The average PM2.5 concentration was 73.0±70.7 μg m‑3 during the measurement. The particulate pollution showed distinct 4-7 days cycles controlled by the meteorological conditions. Each cycle started with low PM2.5 mass concentrations (<20 μg m‑3), since the air mass was from relatively clean mountainous area. The particle number concentrations were high, but and the sizes were small (<30 nm) at this stage, which can be explained by the new particle formation. In the succeeding days, both the particle mass and size continuously increased. The PM2.5concentration increased rapidly by >60 μg day‑1, and the particle mean diameter grew to >100 nm. It is interesting to note that the mean diameters showed similar trend to PM2.5 mass concentrations, indicating the particle pollution attributed to the growth of the newly formed small particles. During the measurement, the average particle densities are between 1.3-1.5 g cm‑3, indicating organics and sulfate were dominant in the particles. The densities of smaller particles, i.e. 46 nm, 81nm, showed single peak at 1.3-1.5 g cm‑3, indicating the particles are internal mixed sulfate and organics. While the 150nm and 240 nm particle densities exhibited bimodal distribution with an additional small peak at ˜1.1 g cm‑3, which is considered as external mixed organic

  6. Drop tower Beijing and short-time microgravity experiments

    NASA Astrophysics Data System (ADS)

    Wan, S. H.; Yin, M. G.; Guan, X. D.; Lin, H.; Xie, J. C.; Hu, Wen-Rui

    Being an important, large ground-based experiment facility for microgravity science, the drop tower of National Microgravity Lab, CAS was founded in 2003 and, since then, has been un-dertaking the experiments to meet the requirements in microgravity research. The 116 meters high drop tower is located in Zhong Guan Cun district, the scientific town of Beijing. Main components of the facility consist of the drop capsule, release mechanism and deceleration and recovery devices, and were developed with particular technical characteristics. Inner space of the drop tower was not vacuumed during the experiment, and a dual capsule system was adopted. The dual capsule comprises an inner and an outer capsule, and there is a space between in the evacuated atmosphere of 30 Pa. During the free fall, the outer capsule falls in normal atmospheric condition, and the inner capsule falls in vacuum. In addition, a single capsule configuration is also available for experiments w of lower gravity level. The residual acceleration is 10-5go or 10-3g0 related to dual capsule or single capsule arrangement respec-tively. An electric magnetic release system was used to release the capsule from position of 83 meters in height. The designed structure of the release mechanism guaranteed the release disturbance to be small enough. An elastic controllable decelerated system, consisted of the reversible mechanic/electric energy transducer, steel cables and rings, string bag, elastic rub-ber stringassembly, energy dissipation resistance, controlling computer system, was used in the drop tower facility. This system is effective to reduce the impact acceleration to a level of 15g0. The experiment data can be recorded by an on-board data acquisition and control system, and transmitted wirelessly to the control room. Many experiments related to the fluid physics, combustion, material science and other field have been successfully conducted by using the short-time microgravity facility of drop tower in

  7. Subfoveal Choroidal Thickness and Glaucoma. The Beijing Eye Study 2011

    PubMed Central

    Wang, Ya Xing; Xu, Liang; Shao, Lei; Zhang, Ya Qin; Yang, Hua; Da Wang, Jin; Jonas, Jost B.; Wei, Wen Bin

    2014-01-01

    Purpose To examine subfoveal choroidal thickness (SFCT) in eyes with glaucoma, using enhanced depth imaging spectral domain optical coherence tomography. Methods The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years (range: 50–93 years). A detailed ophthalmic examination was performed including spectral-domain optical coherence tomography (SD-OCT) with enhanced depth imaging for measurement of SFCT, and assessment of fundus photographs for presence of glaucoma. In addition, the group of patients with chronic angle-closure glaucoma (ACG) from the Beijing Eye Study (n = 37) was merged with a group of patients with chronic ACG from the Tongren hospital (n = 52). Results Assessments of SFCT and glaucoma were available for 3232 (93.2%) subjects. After adjusting for age, axial length, gender, anterior chamber and lens thickness, SFCT was not significantly associated with presence of glaucoma (P = 0.08; regression coefficient B:−15.7). As a corollary, in logistic regression analysis with adjustment for age, axial length and intraocular pressure, presence of glaucoma was not significantly associated with SFCT (P = 0.20). If only open-angle glaucoma was considered, multivariate analysis revealed no significant association between SFCT and presence of open-angle glaucoma (P = 0.44). As a corollary, in logistic regression analysis, open-angle glaucoma was not significantly associated with SFCT (P = 0.91). In a similar manner if only ACG was taken into account, SFCT was not significantly associated with the presence of ACG (P = 0.27) in multivariate analysis. As a corollary in binary regression analysis, presence of ACG was not significantly associated with SFCT (P = 0.27). Conclusions In multivariate analysis with adjustment for age, axial length, gender, anterior chamber and lens thickness, neither OAG nor ACG was associated with an abnormal SFCT. PMID:25210857

  8. Dominant modern sublineages and a new modern sublineage of Mycobacterium tuberculosis Beijing family clinical isolates in Heilongjiang Province, China.

    PubMed

    Li, Di; Dong, Cai-Bo; Cui, Jia-Yi; Nakajima, Chie; Zhang, Chun-Lei; Pan, Xin-Ling; Sun, Gao-Xiang; Dai, En-Yu; Suzuki, Yasuhiko; Zhuang, Min; Ling, Hong

    2014-10-01

    Mycobacterium tuberculosis Beijing family includes a variety of sublineages. Knowledge of the distribution of a certain sublineage of the Beijing family may help to understand the mechanisms of its rapid spread and to establish an association between a certain genotype and the disease outcome. We have previously found that M. tuberculosis Beijing family clinical isolates represent approximately 90% of the clinical isolates from Heilongjiang Province, China. To clarify the distribution of M. tuberculosis Beijing family sublineages in Heilongjiang Province, China and to investigate the regularity rule for their evolution, we examined single nucleotide polymorphisms (SNPs) of 250 M. tuberculosis Beijing family clinical isolates using 10 SNP loci that have been identified as appropriate for defining Beijing sublineages. After determining the sequence type (ST) of each isolate, the sublineages of all M. tuberculosis Beijing family isolates were determined, and phylogenetic analysis was performed. We found that 9 out of the 10 SNP loci displayed polymorphisms, but locus 1548149 did not. In total, 92.8% of the isolates in Heilongjiang Province are modern sublineages. ST10 is the most prevalent sublineage (ST10 and ST22 accounted for 63.2% and 23.6% of all the Beijing family isolates, respectively). A new ST, accounting for 4% of the Beijing family isolates in this area, was found for the first time. Each new ST isolate showed a unique VNTR pattern, and none were clustered. The present findings suggest that controlling the spread of these modern sublineages is important in Heilongjiang Province and in China. PMID:25111610

  9. Whole genome sequencing identifies circulating Beijing-lineage Mycobacterium tuberculosis strains in Guatemala and an associated urban outbreak

    PubMed Central

    Saelens, Joseph W.; Lau-Bonilla, Dalia; Moller, Anneliese; Medina, Narda; Guzmán, Brenda; Calderón, Maylena; Herrera, Raúl; Sisk, Dana M.; Xet-Mull, Ana M.; Stout, Jason E.; Arathoon, Eduardo; Samayoa, Blanca; Tobin, David M.

    2015-01-01

    Summary Limited data are available regarding the molecular epidemiology of Mycobacterium tuberculosis (Mtb) strains circulating in Guatemala. Beijing-lineage Mtb strains have gained prevalence worldwide and are associated with increased virulence and drug resistance, but there have been only a few cases reported in Central America. Here we report the first whole genome sequencing of Central American Beijing-lineage strains of Mtb. We find that multiple Beijing-lineage strains, derived from independent founding events, are currently circulating in Guatemala, but overall still represent a relatively small proportion of disease burden. Finally, we identify a specific Beijing-lineage outbreak centered on a poor neighborhood in Guatemala City. PMID:26542222

  10. Whole genome sequencing identifies circulating Beijing-lineage Mycobacterium tuberculosis strains in Guatemala and an associated urban outbreak.

    PubMed

    Saelens, Joseph W; Lau-Bonilla, Dalia; Moller, Anneliese; Medina, Narda; Guzmán, Brenda; Calderón, Maylena; Herrera, Raúl; Sisk, Dana M; Xet-Mull, Ana M; Stout, Jason E; Arathoon, Eduardo; Samayoa, Blanca; Tobin, David M

    2015-12-01

    Limited data are available regarding the molecular epidemiology of Mycobacterium tuberculosis (Mtb) strains circulating in Guatemala. Beijing-lineage Mtb strains have gained prevalence worldwide and are associated with increased virulence and drug resistance, but there have been only a few cases reported in Central America. Here we report the first whole genome sequencing of Central American Beijing-lineage strains of Mtb. We find that multiple Beijing-lineage strains, derived from independent founding events, are currently circulating in Guatemala, but overall still represent a relatively small proportion of disease burden. Finally, we identify a specific Beijing-lineage outbreak centered on a poor neighborhood in Guatemala City. PMID:26542222

  11. Impacts of urban expansion and future green planting on summer precipitation in the Beijing metropolitan area

    NASA Astrophysics Data System (ADS)

    Zhang, Chao Lin; Chen, Fei; Miao, Shi Guang; Li, Qing Chun; Xia, Xiang Ao; Xuan, Chun Yi

    2009-01-01

    In this study, an analysis of long-term rainfall data reveals that the rapid urban expansion in Beijing since 1981 is statistically correlated to summer rainfall reduction in the northeast areas of Beijing from 1981 to 2005. This coincides with the period in which the shortage of water in the Beijing area has become a serious factor for sustainable economic development. Meanwhile, an analysis of the aerosol optical depth (AOD) from the Total Ozone Mapping Spectrometer spanning the years from 1980 to 2001 shows that there is no clear secular trend in summer AOD in Beijing. With the particular purpose of further understanding the effects of urban expansion on summer rainfall and the potential measures to mitigate such effects, a mesoscale weather/land-surface/urban-coupled model along with different urban land-use change scenarios are used to conduct numerical simulations for two selected heavy summer rainfall events with different, but representative, summer weather patterns in Beijing. Results show that urban expansion can produce less evaporation, higher surface temperatures, larger sensible heat fluxes, and a deeper boundary layer. This leads to less water vapor, more mixing of water vapor in the boundary layer, and hence less (more) convective available potential energy (convective inhibition energy). The combination of these factors induced by expanding urban surfaces is helpful in reducing precipitation for the Beijing area in general and, in particular, for the Miyun reservoir area (the major source for the local water supply). Increasing green vegetation coverage in the Beijing area would produce more rainfall, and model results show that planting grass seems more effective than planting trees. For the same vegetation, the rainfall difference from simulations using two green-planting layouts (annular and cuneiform) is small.

  12. Study on particulate matter air pollution in Beijing with MODIS aerosol level 2 products

    NASA Astrophysics Data System (ADS)

    Mao, Jietai; Li, Chengcai; Lau, Alexis K.

    2004-09-01

    In the run-up to the 2008 Olympic Games in Beijing, Chinese government officials at both the central and municipal levels are keenly aware that they must transform Beijing into a world-class city. According to the Beijing Municipal Environmental Protection Bureau (BJEPB) to improve its air quality some actions are adopting, including taking steps to increase the forested area surrounding the city preventing dust storms, reducing the automotive vehicles, moving polluting factories now inside the fourth ring road ringing the inner city to locations outside of the fourth ring road, and switching the fuel of public buses and taxis from diesel to natural gas, etc. Will they eliminate most serious environmental problems in Beijing? MODIS aerosol products are helping us to answer this kind of questions. A long-term validation has been finished by sun-photometer observations, and the results proved the relative error of MODIS level 2 products was slightly larger than the estimation of Chu et al. (2002) from the results in most AERONET sites. However, the comparison between the products and moisture-corrected air pollution index (API) data, which were daily released to public by EPB, showed a high correlation coefficient. An air pollution episode in 2003 was investigated by the usage of satellite products. Our conclusion for the air pollution control strategy in Beijing is that only reducing the pollution sources from inner city can't fully solve the pollution problems in Beijing and the regional transports from the nearby southern provinces are contributing a lot to the pollution situation in Beijing.

  13. Modeling regional/urban ozone and particulate matter in Beijing, China.

    PubMed

    Fu, Joshua S; Streets, David G; Jang, Carey J; Hao, Jiming; He, Kebin; Wang, Litao; Zhang, Qiang

    2009-01-01

    This paper examines Beijing air quality in the winter and summer of 2001 using an integrated air quality modeling system (Fifth Generation Mesoscale Meteorological Model [MM5]/Community Multiscale Air Quality [CMAQ]) in nested mode. The National Aeronautics and Space Administration (NASA) Transport and Chemical Evolution over the Pacific (TRACE-P) emission inventory is used in the 36- (East Asia), 12- (East China), and 4-km (greater Beijing area) domains. Furthermore, we develop a local Beijing emission inventory that is used in the 4-km domain. We also construct a corroborated mapping of chemical species between the TRACE-P inventory and the Carbon Bond IV (CB-IV) chemical mechanism before the integrated modeling system is applied to study ozone (O3) and particulate matter (PM) in Beijing. Meteorological data for the integrated modeling runs are extracted from MM5. Model results show O3 hourly concentrations in the range of 80-159 parts per billion (ppb) during summer in the urban areas and up to 189 ppb downwind of the city. High fine PM (PM2.5) concentrations (monthly average of 75 microg x m(-3) in summer and 150 microg x m(-3) in winter) are simulated over the metropolitan and down-wind areas with significant secondary constituents. A comparison against available O3 and PM measurement data in Beijing is described. We recommend refinements to the developed local Beijing emission inventory to improve the simulation of Beijing's air quality. The 4-km modeling configuration is also recommended for the development of air pollution control strategies. PMID:19216186

  14. Modeling regional/urban ozone and particulate matter in Beijing, China.

    SciTech Connect

    Fu, J.S.; Streets, D.G.; Jang, C.J.; Hao, J.; He, K.; Wang, L.; Zhang, Q.

    2009-01-15

    This paper examines Beijing air quality in the winter and summer of 2001 using an integrated air quality modeling system (Fifth Generation Mesoscale Meteorological Model (MM5)/Community Multiscale Air Quality (CMAQ)) in nested mode. The National Aeronautics and Space Administration (NASA) Transport and Chemical Evolution over the Pacific (TRACE-P) emission inventory is used in the 36- (East Asia), 12- (East China), and 4-km (greater Beijing area) domains. Furthermore, we develop a local Beijing emission inventory that is used in the 4-km domain. We also construct a corroborated mapping of chemical species between the TRACE-P inventory and the Carbon Bond IV (CB-IV) chemical mechanism before the integrated modeling system is applied to study ozone (O{sub 3}) and particulate matter (PM) in Beijing. Meteorological data for the integrated modeling runs are extracted from MM5. Model results show O{sub 3} hourly concentrations in the range of 80-159 parts per billion (ppb) during summer in the urban areas and up to 189 ppb downwind of the city. High fine PM (PM2.5) concentrations (monthly average of 75 {mu}g.m{sup -3} in summer and 150 {mu}g.m{sup -3} in winter) are simulated over the metropolitan and down-wind areas with significant secondary constituents. Major sources of particulates were biomass burning, coal combustion and industry. A comparison against available O{sub 3} and PM measurement data in Beijing is described. We recommend refinements to the developed local Beijing emission inventory to improve the simulation of Beijing's air quality. The 4-km modeling configuration is also recommended for the development of air pollution control strategies. 31 refs., 5 figs., 3 tabs.

  15. The characteristics of brown carbon aerosol during winter in Beijing

    NASA Astrophysics Data System (ADS)

    Cheng, Yuan; He, Ke-bin; Du, Zhen-yu; Engling, Guenter; Liu, Jiu-meng; Ma, Yong-liang; Zheng, Mei; Weber, Rodney J.

    2016-02-01

    Brown carbon (i.e., light-absorbing organic carbon, or BrC) exerts important effects on the environment and on climate in particular. Based on spectrophotometric absorption measurements on extracts of bulk aerosol samples, this study investigated the characteristics of BrC during winter in Beijing, China. Organic compounds extractable by methanol contributed approximately 85% to the organic carbon (OC) mass. Light absorption by the methanol extracts exhibited a strong wavelength dependence, with an average absorption Ångström exponent of 7.10 (fitted between 310 and 450 nm). Normalizing the absorption coefficient (babs) measured at 365 nm to the extractable OC mass yielded an average mass absorption efficiency (MAE) of 1.45 m2/g for the methanol extracts. This study suggests that light absorption by BrC could be comparable with black carbon in the spectral range of near-ultraviolet light. Our results also indicate that BrC absorption and thus BrC radiative forcing could be largely underestimated when using water-soluble organic carbon (WSOC) as a surrogate for BrC. Compared to previous work relying only on WSOC, this study provides a more comprehensive understanding of BrC aerosol based on methanol extraction.

  16. [Characteristic of Particulate Emissions from Concrete Batching in Beijing].

    PubMed

    Xue, Yi-feng; Zhou, Zhen; Zhong, Lian-hong; Yan, Jing; Qu, Song; Huang, Yu-hu; Tian, He- zhong; Pan, Tao

    2016-01-15

    With the economic development and population growth in Beijing, there is a strong need for construction and housing, which leads to the increase of the construction areas. Meanwhile, as a local provided material, the production of concrete has been raised. In the process of concrete production by concrete batching, there are numerous particulates emitted, which have large effect on the atmospheric environment, however, systematic study about the tempo-spatial characteristics of pollutant emission from concrete batching is still rare. In this study, we estimated the emission of particulates from concrete batching from 1991 to 2012 using emission factor method, analyzed the tempo-spatial characteristics of pollutant emission, established the uncertainty range by adopting Monte-Carlo method, and predicted the future emission in 2020 based on the relative environmental and economical policies. The results showed that: (1) the emissions of particulates from concrete batching showed a trend of "first increase and then decrease", reaching the maximum in 2005, and then decreased due to stricter emission standard and enhanced environmental management. (2) according to spatial distribution, the emission of particulates from concrete batch mainly concentrated in the urban area with more human activities, and the area between the fifth ring and the sixth ring contributed the most. (3) through scenarios analysis, for further reducing the emission from concrete batching in 2020, more stricter standard for green production as well as powerful supervision is needed. PMID:27078945

  17. Uncultivated Magnetotactic Cocci from Yuandadu Park in Beijing, China▿

    PubMed Central

    Lin, Wei; Pan, Yongxin

    2009-01-01

    In the present study, we investigated a group of uncultivated magnetotactic cocci, which was magnetically isolated from a freshwater pond in Beijing, China. Light and transmission electron microscopy showed that these cocci ranged from 1.5 to 2.5 μm and contained two to four chains of magnetite magnetosomes, which sometimes were partially disorganized. Overall, the size of the disorganized magnetosomes was significantly smaller than that arranged in chains. All characterized magnetosome crystals were elongated (shape factor = 0.64) and fall into the single-domain size range (30 to 115 nm). Comparative 16S rRNA gene sequence analysis and fluorescence in situ hybridization showed that the enriched bacteria were a virtually homogeneous population and represented a novel lineage in the Alphaproteobacteria. The closest cultivated relative was magnetotactic coccoid strain MC-1 (88% sequence identity). First-order reversal curve diagrams revealed that these cocci had relatively strong magnetic interactions compared to the single-chain magnetotactic bacteria. Low-temperature magnetic measurements showed that the Verwey transition of them was ∼108 K, confirming magnetite magnetosomes, and the delta ratio δFC/δZFC was >2. Based on the structure, phylogenetic position and magnetic properties, the enriched magnetotactic cocci of Alphaproteobacteria are provisionally named as “Candidatus Magnetococcus yuandaducum.” PMID:19376904

  18. Risk factors for epithelial ovarian cancer in Beijing, China.

    PubMed

    Chen, Y; Wu, P C; Lang, J H; Ge, W J; Hartge, P; Brinton, L A

    1992-02-01

    A study in Beijing, China of 112 pathologically confirmed epithelial ovarian cancer cases and 224 age-matched community controls enabled evaluation of risk in relation to reproductive, medical, familial, and selected lifestyle factors. An inverse relationship was observed between the number of full-term pregnancies and ovarian cancer risk. Compared to nulliparous women, subjects with one, two, or three full-term pregnancies were at 50%, 70%, or 90% reduced risks, respectively (P for trend less than 0.01). A positive correlation was found between the number of ovulatory years and risk, with a 2.6-fold increased risk for women with 30 or more compared to less than 10 ovulatory years (P for trend less than 0.01). Infertility, as estimated in various ways, was also found to be an important risk factor. When parity was taken into account, age at first pregnancy was not related to ovarian cancer risk. No protective effect was associated with mumps virus infection. In contrast, risk increased significantly as serum mumps virus antibody titres increased (P for trend less than 0.01). An elevated risk was found in women with a history of long-term (greater than 3 months) application of talc-containing dusting powder to the lower abdomen and perineum (Relative risk 3.9, 95% confidence interval: 0.9-10.63). These findings suggest that Chinese women have risk factors similar to those of occidental women. PMID:1544753

  19. [Emission Characteristics of VOCs from Typical Restaurants in Beijing].

    PubMed

    Cui, Tong; Cheng, Jing-chen; He, Wan-qing; Ren, Pei-fang; Nie, Lei; Xu, Dong-yao; Pan, Tao

    2015-05-01

    Using the EPA method, emission of volatile organic compounds (VOCs) , sampled from barbecue, Chinese and Western fast-food, Sichuan cuisine and Zhejiang cuisine restaurants in Beijing was investigated. VOCs concentrations and components from different cuisines were studied. The results indicated that based on the calibrated baseline ventilation volume, the VOCs emission level from barbecue was the highest, reaching 12.22 mg · m(-3), while those from fast-food of either Chinese or Western, Sichuan cuisine and Zhejiang cuisine were about 4 mg · m(-3). The components of VOCs from barbecue were different from those in the other cuisines, which were mainly propylene, 1-butene, n-butane, etc. The non-barbecue cuisines consisted of high concentration of alcohols, and Western fast-food contained relatively high proportion of aldehydes and ketones organic compounds. According to emission concentration of baseline ventilation volume, barbecue released more pollutants than the non-barbecue cuisines at the same scale. So, barbecue should be supervised and controlled with the top priority. PMID:26314095

  20. Characteristics and cellular effects of ambient particulate matter from Beijing.

    PubMed

    Lu, Yan; Su, Shu; Jin, Wenjie; Wang, Bin; Li, Ning; Shen, Huizhong; Li, Wei; Huang, Ye; Chen, Han; Zhang, Yanyan; Chen, Yuanchen; Lin, Nan; Wang, Xilong; Tao, Shu

    2014-08-01

    In vitro tests using human adenocarcinomic alveolar epithelial cell line A549 and small mouse monocyte-macrophage cell line J774A.1 were conducted to test toxicity of six PM (particulate matter) samples from Beijing. The properties of the samples differ significantly. The production of inflammatory cytokine (TNF-α for J774A.1) and chemokine (IL-8 for A549) and the level of intracellular reactive oxygen species (ROS) were used as endpoints. There was a positive correlation between water soluble organic carbon and DTT-based redox activity. Both cell types produced increased levels of inflammatory mediators and had higher level of intracelllar ROS, indicating the presence of PM-induced inflammatory response and oxidative stress, which were dose-dependent and significantly different among the samples. The releases of IL-8 from A549 and TNF-α from J774A.1 were significantly correlated to PM size, Zeta potential, endotoxin, major metals, and polycyclic aromatic hydrocarbons. No correlation between ROS and these properties was identified. PMID:24811947

  1. Air quality impacts of power plant emissions in Beijing.

    PubMed

    Hao, Jiming; Wang, Litao; Shen, Minjia; Li, Lin; Hu, Jingnan

    2007-05-01

    The CALMET/CALPUFF modeling system was applied to estimate the air quality impacts of power plants in 2000 and 2008 in Beijing, and the intake fractions (IF) were calculated to see the public health risks posed. Results show that in 2000 the high emission contribution induced a relatively small contribution to average ambient concentration and a significant impact on the urban area (9.52 microg/m(3) of SO(2) and 5.29 microg/m(3) of NO(x)). The IF of SO(2), NO(x) and PM(10) are 7.4 x 10(-6), 7.4 x 10(-6) and 8.7 x 10(-5), respectively. Control measures such as fuel substitution, flue gas desulfurization, dust control improvement and flue gas denitration planned before 2008 will greatly mitigate the SO(2) and PM(10) pollution, especially alleviating the pressure on the urban area to reach the National Ambient Air Quality Standard (NAAQS). NO(x) pollution will be mitigated with 34% decrease in concentration but further controls are still needed. PMID:16899328

  2. [Observational study of atmospheric HONO in summer of Beijing].

    PubMed

    Zhu, Yan-Wu; Liu, Wen-Qing; Xie, Pin-Hua; Dou, Ke; Liu, Shi-Sheng; Si, Fu-Qi; Li, Su-Wen; Qin, Min

    2009-06-15

    The concentration of HONO, NO2, O3 and other atmospheric pollutants were observed continuously by using differential optical absorption spectroscopy (DOAS) from 2007-08-14 to 2007-08-24 in Beijing, China. Diurnal variation characteristics of HONO and NO2 were analyzed. The HONO levels originated from the nocturnal direct emission were discussed. And the correlation between the heterogeneous formation of HONO and its related factors (BC, RH, and so on) was studied. The results showed that HONO had two peaks at about 01:00 and 06:00, respectively, while two peaks of NO2 concentrations appeared at about 01:00 and 07:00. The highest HONO(em)/HONO ratio of 31.3% was observed at about 20:00 between 19:00 to 07:00, and the average ratio was 15%. Good correlation of HONO(corr)/NO2 ratio with BC and RH at night was obtained. The correlation suggested that heterogeneous NO2 to HONO conversion processes may occur on BC surfaces by reaction with absorption water, and the average nighttime conversion frequency from NO2 into HONO (HONO/NO2) was calculated about 0.8% x h(-1). At the same time, the results showed that heterogeneous formation of HONO was increased with RH and inhibited at RH > 80%, and the hypothesis was further supported by detailed analysis of selected case. PMID:19662832

  3. Carbon dioxide fluxes from an urban area in Beijing

    NASA Astrophysics Data System (ADS)

    Song, Tao; Wang, Yuesi

    2012-03-01

    A better understanding of urban carbon dioxide (CO 2) emissions is important for quantifying urban contributions to the global carbon budget. From January to December 2008, CO 2 fluxes were measured, by eddy covariance at 47 m above ground on a meteorological tower in a high-density residential area in Beijing. The results showed that the urban surface was a net source of CO 2 in the atmosphere. Diurnal flux patterns were similar to those previously observed in other cities and were largely influenced by traffic volume. Carbon uptake by both urban vegetation during the growing season and the reduction of fuel consumption for domestic heating resulted in less-positive daily fluxes in the summer. The average daily flux measured in the summer was 0.48 mg m - 2 s - 1 , which was 82%, 35% and 36% lower than those in the winter, spring and autumn, respectively. The reduction of vehicles on the road during the 29th Olympic and Paralympic Games had a significant impact on CO 2 flux. The flux of 0.40 mg m - 2 s - 1 for September 2008 was approximately 0.17 mg m - 2 s - 1 lower than the flux for September 2007. Annual CO 2 emissions from the study site were estimated at 20.6 kg CO 2 m - 2 y - 1 , considerably higher than yearly emissions obtained from other urban and suburban landscapes.

  4. [Community Structure and Succession of Methanogens in Beishenshu Landfill, Beijing].

    PubMed

    Song, Li-na; Wang, Lei; Xia, Meng-jing; Su, Yue; Li, Zhen-shan

    2015-09-01

    Methanogens are the key microorganisms for landfill stabilization. RT-PCR and qPCR detecting system were employed to determine the types and abundance of methanogens in 2-15 year-old solid wastes that sampled from Beishenshu Landfill, Beijing. The organic components were almost stable and the pH values were in alkaline range, which indicated that the landfill was in the methanogenic process. Methanobacterials, Methanosaeta, and Methanosarcina were detected, among which Methanosaeta and Methanosarcina are acetoclastic, and Methanobacterials are hydrogenotrophic. As landfill processing, within this time range, although the bacterial abundance was significantly decreased, the amount of methanogens was first increased and then decreased, and finally became stable after being landfilled for 9 years. Methanosarcina was the dominate taxa. Significant correlations were found between the methanogens and the volatile fatty acids, but the correlations between methanogens and larger molecular organic matters were relatively weak or even absent. Taken together, our study revealed that the amount of methanogens were affected by substrates, but hardly influenced by the conversion of large molecules in these wastes landfilled for more than 2 years. PMID:26717715

  5. A novel approach for urbanization level evaluation based on information entropy principle: A case of Beijing

    NASA Astrophysics Data System (ADS)

    Zhao, Jingjing; Chai, Lihe

    2015-07-01

    Urbanization level evaluation (ULE) is an important scientific basis for guiding urban managers to make decisions. By introducing information entropy to describe the interactions between all indicators, a holistic structural parameter ξ, its dynamic equation and self-organizing feature map simulation technique are derived to describe the structural evolution of the indicator network. In this way, a novel ULE model is universally proposed. Then, we use the model to assess the evolutionary urbanization level of Beijing during 2005-2012. We calculate structural parameter ξ values of the indicator network with 35 microscopic indicators as nodes. The results show Beijing's urbanization level has ever kept increasing. Large increase of ξ values in 2008 and 2012 represented significant improvements of urbanization level in these two years, while a rapid adjustment of urbanization development occurred in 2010. Five meso-scopic subsystems as urban construction, economic development, social development, ecological environment and urban-rural development affected Beijing's urbanization level in different ways. The radar chart of the model shows the contributions of economic development and urban-rural development to Beijing's urbanization changed most, while poor coordination of urban-rural development largely existed. By showing Beijing's ULE based on two analytical ways, we further discuss the objectivity and flexibility in choosing indicator network. Finally, beyond the application case, we discuss the universality and superiority of the new model.

  6. Polybrominated diphenyl ethers in soil from three typical industrial areas in Beijing, China.

    PubMed

    Zhang, Yongfei; Fu, Shan; Liu, Xinchun; Li, Zheng; Dong, Yuan

    2013-12-01

    Areas containing industrial facilities belonging to three different typical industries that may cause pollution by polybrominated diphenyl ethers (PBDEs) in Beijing, China were investigated. Specifically, the areas contained a solid waste incineration plant, a chemical factory, and a heat and power plant. Investigation of the pollution status of PBDEs in the surface soil from areas around these industries revealed the highest concentration of 42 PBDE congeners (118 ng/g, dry mass) at the solid waste incineration plant. In the other two plants, the highest concentrations were both 26 ng/g (dry mass). Among the PBDE homologues, the PBDE contamination at all sites showed similar congener compositions, with BDE 209 being the dominant congener. Our findings established the first contamination status of three typical industrial areas in Beijing. Furthermore, the total concentrations of 42 PBDE congeners tended to decrease as the distance from the investigated plants increased. Overall, these plants were identified as potential pollution sources of PBDEs in Beijing. Moreover, Pearson correlation analysis revealed that the major PBDE source in Beijing may be associated with the technical deca-BDE and penta-BDE mixture. Based on the data obtained in this preliminary investigation, further study of the potential of these sources to emit PBDEs in Beijing is warranted. PMID:24649676

  7. Health impacts and economic losses assessment of the 2013 severe haze event in Beijing area.

    PubMed

    Gao, Meng; Guttikunda, Sarath K; Carmichael, Gregory R; Wang, Yuesi; Liu, Zirui; Stanier, Charles O; Saide, Pablo E; Yu, Man

    2015-04-01

    Haze is a serious air pollution problem in China, especially in Beijing and surrounding areas, affecting visibility, public health and regional climate. In this study, the Weather Research and Forecasting-Chemistry (WRF-Chem) model was used to simulate PM2.5 (particulate matters with aerodynamic diameter≤2.5 μm) concentrations during the 2013 severe haze event in Beijing, and health impacts and health-related economic losses were calculated based on model results. Compared with surface monitoring data, the model results reflected pollution concentrations accurately (correlation coefficients between simulated and measured PM2.5 were 0.7, 0.4, 0.5 and 0.6 in Beijing, Tianjin, Xianghe and Xinglong stations, respectively). Health impacts assessments show that the PM2.5 concentrations in January might cause 690 (95% confidence interval (CI): (490, 890)) premature deaths, 45,350 (95% CI: (21,640, 57,860)) acute bronchitis and 23,720 (95% CI: (17,090, 29,710)) asthma cases in Beijing area. Results of the economic losses assessments suggest that the haze in January 2013 might lead to 253.8 (95% CI: (170.2, 331.2)) million US$ losses, accounting for 0.08% (95% CI: (0.05%, 0.1%)) of the total 2013 annual gross domestic product (GDP) of Beijing. PMID:25585158

  8. Evaluating Beijing's human carrying capacity from the perspective of water resource constraints.

    PubMed

    Zhang, Yingxuan; Chen, Min; Zhou, Wenhua; Zhuang, Changwei; Ouyang, Zhiyun

    2010-01-01

    As the demands on limited water resources intensify, concerns are being raised about the human carrying capacity of these resources. However, few researchers have studied the carrying capacity of regional water resources. Beijing, the second-largest city in China, faces a critical water shortage that will limit the city's future development. We developed a method to quantify the carrying capacity of Beijing's water resources by considering water-use structures based on the proportions of water used for agricultural, industrial, and domestic purposes. We defined a reference structure as 45:22:33 (% of total, respectively), an optimized structure as 40:20:40, and an ideal structure as 50:15:35. We also considered four domestic water quotas: 55, 75, 95, and 115 m3/(person x yr). The urban carrying capacity of 10-12 million was closest to Beijing's actual 2003 population for all three water-use structures with urban domestic water use of 75 m3/(person x yr). However, after accounting for our underlying assumptions, the adjusted carrying capacity is closer to 5-6 million. Thus, Beijing's population in 2003 was almost twice the adjusted carrying capacity. Based on this result, we discussed the ecological and environmental problems created by Beijing's excessive population and propose measures to mitigate these problems. PMID:21179972

  9. Diurnal, weekly and monthly spatial variations of air pollutants and air quality of Beijing

    NASA Astrophysics Data System (ADS)

    Chen, Wei; Tang, Hongzhao; Zhao, Haimeng

    2015-10-01

    Under the National Ambient Air Quality Standard released in 2012 (NAAQS-2012), Beijing began to publicize hourly Air Quality Index as well as real time concentrations of 6 pollutants in its web platform to provide detailed information for air quality assessment from 2013. In this study, hourly air quality monitoring data from May 2014 to April 2015 were collected for all 35 monitoring stations in Beijing to analyze the temporal and spatial variations of air pollutants and air quality. It is found that in spatial pattern, the air qualities in southern and northern Beijing are totally different. The association between heavy pollution concentrations and wind situations suggested that neighboring area's air quality has an important role in the air quality of Beijing combining with air quality attainment rates in all 35 monitoring stations and northern China. For temporal variations, late night and early morning are the most polluted time while afternoon is the least polluted time for all pollutants except O3 with most polluted time in afternoon. Summer time in Beijing has the best air quality while winter time has the worst air quality coinciding with the heating season in the winter.

  10. [Change of resource environmental bearing capacity of Beijing-Tianjin-Hebei region and its driving factors].

    PubMed

    Guo, Ke; Wang, Li-qun

    2015-12-01

    Based on the evaluation index system established for measuring the resource environmental bearing capacity (REBC), this paper measured the REBC of Beijing-Tianjin-Hebei region by applying the state space model and analyzed their driving factors by using the Tobit model. The results showed that the REBC of Beijing-Tianjin-Hebei region was in the available state and at the rising stage as well during 2000-2012. The social economic growth had great pressure on the resources and environment. The bearing ratios of the REBCs of Beijing, Tianjin and Hebei all presented a U curve and located at low levels, which meant that there was high REBC potential in these regions. Both of the permanent population and the urban residents 'Engel' s coefficient were the influence factors of the REBC of Beijing-Tianjin-Hebei region. The population problem was likely to become the bottleneck to restrict the regional social and economic development, and also threaten the resources and environment. The specific driving factors of the REBC were different in Beijing, Tianjin and Hebei. For example, energy consumption per unit of GDP only had significant impact on Tianjin. At last, the paper proposed that the three regions should complement each other in resources and environment, social development, and economic structure, also the REBC should be taken a reference in decision and policy making. PMID:27112024

  11. Travelling to china for the beijing 2008 olympic and paralympic games.

    PubMed

    Shaw, Marc T M; Leggat, Peter A; Borwein, Sarah

    2007-11-01

    The 29th modern Olympic Summer Games, conducted once every 4 years since 1896, will be held in Beijing, China, from 8 to 24 August 2008. There will be approximately 28 major and 302 minor events in 37 venues in the prominent cities of Beijing, Hong Kong and Shanghai, and also in Qingdao (a coastal town in Shandong Province), Qinhuangdao (northeast of Beijing), Shanghai, Shenyang (an industrial city in Liaoning Province) and in Tianjin (on the coast near Beijing). Following the Olympic Games, the Paralympic Games will be conducted from 6 to 17 September 2008 in Beijing and 20 Paralympic Sports will be represented. This paper focuses on health and safety issues for travellers to China in general, although it makes specific references to advice for visiting Olympic and Paralympic athletes and team staff, who will be travelling to the games. It must be remembered that travel health advice can change, and that travellers should be advised to seek up-to-date travel health advice for China closer to their departure. PMID:17983975

  12. Etude theorique et experimentale des evaporateurs de dioxyde de carbone operant dans des conditions de givrage

    NASA Astrophysics Data System (ADS)

    Bendaoud, Adlane Larbi

    Les evaporateurs de refrigeration sont surtout du type tube a ailettes, appeles serpentins, et fonctionnent dans l'une des conditions suivantes: seche, humide ou avec formation de givre. Il a ete demontre que la formation du givre sur la paroi exterieure de l'echangeur engendre une surconsommation energetique a cause des operations de degivrage puisque 15 a 20% seulement de la chaleur produite sert au degivrage tandis que le reste est dissipee dans l'environnement [1]. Avec l'avenement des nouveaux refrigerants, moins nocifs envers l'environnement, l'industrie du froid se trouve penalisee du fait que peu ou pas de composantes mecaniques (compresseur, pompe, echangeur...etc.) adaptees sont disponibles [3]. Il s'agit pour la communaute des frigoristes de combler ce retard technologique en redeveloppant ces composantes mecaniques afin qu'elles soient adaptees aux nouveaux refrigerants. Dans cette optique, et afin de mieux comprendre le comportement thermique des evaporateurs au CO2 fonctionnant dans des conditions seches, qu'un groupe de chercheurs du CanmetENERGIE avaient lance, en 2000, un programme de R & D. Dans le cadre de programme un outil de simulation des evaporateurs au CO2 a ete developpe et un banc d'essai contenant une boucle secondaire de refrigeration utilisant le CO2 comme refrigerant a ete construit. Comme continuite de ce travail de recherche, en 2006 ce meme groupe de recherche a lance un nouveau projet qui consiste a faire une etude theorique et experimentale des evaporateurs au CO2 operants dans des conditions de givrage. Et, c'est exactement dans le cadre de ce projet que se positionne ce travail de these. Ce travail de recherche a ete entrepris pour mieux comprendre le comportement thermique et hydrodynamique des serpentins fonctionnant dans des conditions de givrage, l'effet des circuits de refrigerant ainsi que celui des parametres geometriques et d'operation. Pour cela, un travail theorique supporte par une etude experimentale a ete effectue

  13. Impact of buildings on surface solar radiation over urban Beijing

    NASA Astrophysics Data System (ADS)

    Zhao, Bin; Liou, Kuo-Nan; Gu, Yu; He, Cenlin; Lee, Wee-Liang; Chang, Xing; Li, Qinbin; Wang, Shuxiao; Tseng, Hsien-Liang R.; Leung, Lai-Yung R.; Hao, Jiming

    2016-05-01

    The rugged surface of an urban area due to varying buildings can interact with solar beams and affect both the magnitude and spatiotemporal distribution of surface solar fluxes. Here we systematically examine the impact of buildings on downward surface solar fluxes over urban Beijing by using a 3-D radiation parameterization that accounts for 3-D building structures vs. the conventional plane-parallel scheme. We find that the resulting downward surface solar flux deviations between the 3-D and the plane-parallel schemes are generally ±1-10 W m-2 at 800 m grid resolution and within ±1 W m-2 at 4 km resolution. Pairs of positive-negative flux deviations on different sides of buildings are resolved at 800 m resolution, while they offset each other at 4 km resolution. Flux deviations from the unobstructed horizontal surface at 4 km resolution are positive around noon but negative in the early morning and late afternoon. The corresponding deviations at 800 m resolution, in contrast, show diurnal variations that are strongly dependent on the location of the grids relative to the buildings. Both the magnitude and spatiotemporal variations of flux deviations are largely dominated by the direct flux. Furthermore, we find that flux deviations can potentially be an order of magnitude larger by using a finer grid resolution. Atmospheric aerosols can reduce the magnitude of downward surface solar flux deviations by 10-65 %, while the surface albedo generally has a rather moderate impact on flux deviations. The results imply that the effect of buildings on downward surface solar fluxes may not be critically significant in mesoscale atmospheric models with a grid resolution of 4 km or coarser. However, the effect can play a crucial role in meso-urban atmospheric models as well as microscale urban dispersion models with resolutions of 1 m to 1 km.

  14. Epidemiological Characteristics of Hypertension in the Elderly in Beijing, China

    PubMed Central

    Tang, Zhe; Li, Yun; Sun, Fei; Diao, Lijun; Ge, Gaizhen; Feng, Ming; Wang, Jieyu

    2015-01-01

    Background/Objectives The prevalence rate of hypertension increases significantly with the aging society, and hypertension is obviously becoming a major health care concern in China. The aim of the study was to explore the epidemiological characteristics of hypertension in the elderly and to provide a basis for the prevention of hypertension. Design 3-cross sectional studies in 2000, 2004, and 2007, respectively. Setting Beijing, China. Participants A group of 2,832, 1,828, and 2,277 elderly residents aged ≥60 years were included this study in 2000, 2004, and 2007, respectively. Intervention None. Measurements Statistical sampling techniques included cluster, stratification, and random selection. Trained staff used a comprehensive geriatric assessment questionnaire and a standard survey instrument to complete the assessments. During the person-to-person interviews, the participants’ demographic characteristics, living conditions, and health status were collected, and their blood pressure was measured. Results The prevalence rates (69.2%, 61.9%, and 56.0%) of hypertension and the control rates (22.6%, 16.7%, and 21.5%) lowered annually, while the awareness rates (43.7%, 55.8%, and 57.6%) of the treatment elevated annually in 2000, 2004, and 2007, respectively. There was no increase in the control rates for males (26.2%, 16.7%, and 20.8%), younger participants (28.0%, 18.4%, and 21.0%), and rural residents (19.5%, 9.6%, and 13.4%) in 2000, 2004, and 2007, respectively. Conclusions Our study findings indicated that the prevalence of hypertension is high in rural elderly participants, while the rates of awareness, treatment, and control were low. This suggests that effective public measures need to be developed to improve the prevention and control of hypertension. PMID:26295836

  15. Assessment of Heavy Metal Pollution in Topsoil around Beijing Metropolis

    PubMed Central

    Sun, Ranhao; Chen, Liding

    2016-01-01

    The topsoil around Beijing metropolis, China, is experiencing impacts of rapid urbanization, intensive farming, and extensive industrial emissions. We analyzed the concentrations of Cu, Ni, Pb, Zn, Cd, and Cr from 87 topsoil samples in the pre-rainy season and 115 samples in the post-rainy season. These samples were attributed to nine land use types: forest, grass, shrub, orchard, wheat, cotton, spring maize, summer maize, and mixed farmland. The pollution index (PI) of heavy metals was calculated from the measured and background concentrations. The ecological risk index (RI) was assessed based on the PI values and toxic-response parameters. The results showed that the mean PI values of Pb, Cr, and Cd were > 1 while those of Cu, Ni, and Zn were < 1. All the samples had low ecological risk for Cu, Ni, Pb, Zn, and Cr while only 15.35% of samples had low ecological risk for Cd. Atmospheric transport rather than land use factors best explained the seasonal variations in heavy metal concentrations and the impact of atmospheric transport on heavy metal concentrations varied according to the heavy metal types. The concentrations of Cu, Cd, and Cr decreased from the pre- to post-rainy season, while those of Ni, Pb, and Zn increased during this period. Future research should be focused on the underlying atmospheric processes that lead to these spatial and seasonal variations in heavy metals. The policymaking on environmental management should pay close attention to potential ecological risks of Cd as well as identifying the transport pathways of different heavy metals. PMID:27159454

  16. [Improvement of Air Quality During APEC in Beijing in 2014].

    PubMed

    Cheng, Nian-liang; Li, Yun-ting; Zhang, Da-wei; Chen, Tian; Li, Ling-jun; Li, Jin; Jiang, Lei

    2016-01-15

    Variations of air quality, meteorological conditions and the effect of pollution control measures on particle matter concentrations in Beijing were all analyzed during APEC (from 1st to 12th in November) in 2014 based on the atmospheric pollutant monitoring data, monitoring components of PM2.5, meteorological and remote sensing data and CMB model. The results showed that the average concentrations of PM2.5, PM10, SO2, NO2 were 43,62,8,46 [g.m respectively during APEC and the average concentrations of PM2.5, PM10, SO2, NO2 were decreased by 45%, 43%, 64% and 31% compared to those in the same period of the last 5 years (PM2. was the average of the last 2 years); the concentrations of PM25 at different sites were decreased by 27.4%-35.5%; the concentrations of PM2.5 in the center of city and northern mountainous areas were the lowest, which dropped by 30%-45% compared to those in the same period of the last 5 years while in the southern area the decrement was below 25%; the main component SO4(2-), the substance of the crust, and NO3- were decreased by 50%, 76%, 35% respectively compared to those in the same period in 2013 and the chemical mass balance (CMB) model analysis results indicated that contributions of coal boiler, dust, motor vehicle were 2%, 7%, 30% respectively during APEC; air pollution control measures (coal, dust and traffic management) had a significant effect on reducing pollutant emissions and the pollutant emissions control reduced the concentration peak and delayed the accumulation speed. PMID:27078942

  17. [Beijing common green tree leaves' accumulation capacity for heavy metals].

    PubMed

    Li, Shao-Ning; Kong, Ling-Wei; Lu, Shao-Wei; Chen, Bo; Gao, Chen; Shi, Yuan

    2014-05-01

    Seasonal variation of heavy metal contents in leaves and their relationships with soil heavy metal pollution levels were studied through measuring and analyzing the leaves of the common tree species in Beijing and soil heavy metal contents, to detect heavy metal accumulation ability of plant leaves. The results showed that: (1) the contents of Cu, Pb, Zn in plant leaves first decreased and then increased, again declined with changing the seasons (from spring to winter). Cr concentration showed the trend of first increase and then decrease from spring to winter, and the highest in the autumn; the accumulation capacities of Cu for Babylonica and Japonica were higher in the spring, summer and autumn, while Tabuliformis was in winter; the higher accumulation capacities for Cr, Pb were Japonica and Platycladus, and in winter were Platycladus and Bungeana; the higher accumulation capacities for Zn were Babylonica and Bungeana, while Platycladus in winter; (2) the pollution degree of four kinds of heavy metals (Cu, Cr, Pb, Zn) from downtown to suburbs showed that: Jingshan (C =2.48, C is contamination factor) > Olympic (C = 1.27) > Songshan (C = 1.20) > Shuiguan (C = 1. 18); (3) the heavy metals concentration of same plant leaves in the water of the Great Wall changed larger, but those in the other three areas showed that: Jingshan > Olympic > Songshan; the ability of same species leaf to absorb different sorts of heavy metals showed that: Zn >Cu >Pb >Cr; the difference between Zn content and Cr content was significant (P <0.01); (4) the relationship between heavy metal content in plant leaves and soil heavy metal pollution levels presented a quadratic polynomial relation; the significant correlation was found between other three heavy metal contents of plant samples and soil samples, but they were not the case for the Cu, and the correlation coefficients were above 0. 9. PMID:25055683

  18. [Particulate matter adsorption capacity of 10 evergreen species in Beijing].

    PubMed

    Wang, Bing; Zhang Wei-kang; Niu, Xiang; Wang, Xiao-yan

    2015-02-01

    In the atmosphere, high concentrations of air particles PM (Particulate matter) cause not only environmental pollution, but also serious harm to human body. Green plants as an air filter, can effectively improve the air quality in urban and suburb, and protect human health. Therefore, it is necessary to understand the adsorption capacity of air particulate matter of different species. Based on aerosol generator (QRJZFSQ-I), the leaf surface of ten plants including six evergreen trees and four evergreen shrubs were measured to determine the atmosphere adsorption (TSP, PM10, PM2.5 and PM10) capacity in Beijing, the results showed that: (1) There was obvious difference in the PM adsorption capacity of the leaf surface of different species, the highest were Cedrus deodara and Pinus tabuliformis, which were (18.95 ± 0.71) μg x cm(-2) and (14.61 ± 0.78) μg x cm(-2) respectively, while Abiesfabri was the minimum, which was (8.02 ± 0.4) μg x cm(-2); (2) There was also difference in the per unit leaf area particulate adhesion ability among different tree species, the tree species with the strongest leaf PM10 adhesion ability were Pinus tabulformis and Cedrus deodara, those with the strongest leaf PM2.5 adhesion ability were Cedrus deodara, Juniperus procumbens , Juniperus chinensis cv. kaizuka and Pinus tabuliformis, while those with the strongest leaf PM10 adhesion ability were Cedrus deodara, Juniperus procumbens, Abies fabri and Pinus tabuliformis; (3) The proportions of particulate matters (PM10 and PM2.5) in TSP were different. PM10 had mainly two kinds of trends in April-June, one was firstly decreasing and then increasing, with the main tree type of the shrub species; and the other was increasing, with the main tree type of the tree species. But this change trend was not obvious in PM2.5. PMID:26031064

  19. A spatial reference frame model of Beijing based on spatial cognitive experiment

    NASA Astrophysics Data System (ADS)

    Zhang, Jie; Zhang, Jing; Liu, Yu

    2006-10-01

    Orientation relation in the spatial relation is very important in GIS. People can obtain orientation information by making use of map reading and the cognition of the surrounding environment, and then create the spatial reference frame. City is a kind of special spatial environment, a person with life experiences has some spatial knowledge about the city where he or she lives in. Based on the spatial knowledge of the city environment, people can position, navigate and understand the meaning embodied in the environment correctly. Beijing as a real geographic space, its layout is very special and can form a kind of new spatial reference frame. Based on the characteristics of the layout of Beijing city, this paper will introduce a new spatial reference frame of Beijing and use two psychological experiments to validate its cognitive plausibility.

  20. Lidar observation campaigns on diurnal variations of the sodium layer in Beijing, China

    NASA Astrophysics Data System (ADS)

    Wang, Jihong

    2016-07-01

    Based on observations from daytime lidars in eastern China, diurnal cycles of the sodium layer over Beijing (40.5°N, 116°E) are investigated. Diurnal variations of Na density, root mean square (RMS) layer width, and centroid height of the sodium layer are analyzed. Results reveal that the large diurnal cycles of the sodium layer are controlled mainly by 24-hr oscillations at the Beijing observation site. The diurnal variation over Beijing was controlled principally by photoionization and photochemistry effects during another campaign, and there was little evidence of direct tidal perturbations. The comparisons suggest that the diurnal variation of the sodium layer perhaps has obvious regional characteristics across China. The variation can be either controlled mainly by tidal perturbations or by photoionization and photochemistry effects in different seasons.

  1. An analysis of periodicities in the 1470 to 1974 Beijing precipitation record

    NASA Technical Reports Server (NTRS)

    Hameed, S.; Yeh, W. M.; Cess, R. D.; Wang, W. C.; Li, M. T.

    1983-01-01

    An analyis of a time series consisting of an annual index of dryness/wetness for the years 1470 to 1974 in Beijing, China is presented. Its power spectrum shows that dominant cycles occur with long periods of the order of 80 years. Cycles with periods of 11 and 22 years are weak or non-existent, but a significant signal at 18.7 years (which is also the period of a component of the lunar tide generating force) is detected. The long term variations in Beijing precipitation appear to lag long term (Gleissberg) variations in solar activity by nearly 75 years. A pattern which spans nearly 150 years in the Beijing record is found to be repeated with notable similarity.

  2. Local and distant source contributions to secondary organic aerosol in the Beijing urban area in summer

    NASA Astrophysics Data System (ADS)

    Lin, Jian; An, Junling; Qu, Yu; Chen, Yong; Li, Ying; Tang, Yujia; Wang, Feng; Xiang, Weiling

    2016-01-01

    Quantification of local and distant source contributions to particulate matter is a key issue to improving air quality in large urban areas, but few studies have focused on secondary organic aerosol (SOA) source contributions in a large area, especially in China. In this study, we extended the Comprehensive Air Quality Model with Extensions (CAMX) version 5.4, replacing the two-product approach by the volatility basis-set (VBS) approach, with updated SOA yields based on smog chamber studies. The modules related to the computationally efficient particulate source apportionment technology (PSAT) used in CAMX v5.4 were extended based on the volatility basis set (VBS) approach. The updated version of the CAMX model was then used to calculate the local and distant source contributions to SOA in Beijing for the first time. The results indicated that the VBS approach substantially improved hourly, daily, and monthly SOA simulations, compared with the two-product approach and the observations. In August 2007, the local source contributions to anthropogenic and biogenic SOA in Beijing were 23.8% and 16.6%, respectively; distant sources dominated for both anthropogenic and biogenic SOA in Beijing: Northern Hebei, Middle Hebei, Northeast China, Inner Mongolia, Shandong, and Tianjin (including Xianghe) contributed 5.1%-18.2% to anthropogenic SOA in Beijing; whereas, Inner Mongolia, Northern Hebei, and Northeast China contributed 12.2%, 18.6%, and 10.1%, respectively, to biogenic SOA in Beijing. Additionally, other areas outside China respectively contributed 5.3% and 10.8% to anthropogenic and biogenic SOA in Beijing: this could be related to strong summer monsoon.

  3. Statistical Analysis of the Impacts of Regional Transportation on the Air Quality in Beijing

    NASA Astrophysics Data System (ADS)

    Huang, Zhongwen; Zhang, Huiling; Tong, Lei; Xiao, Hang

    2016-04-01

    From October to December 2015, Beijing-Tianjin-Hebei (BTH) region had experienced several severe haze events. In order to assess the effects of the regional transportation on the air quality in Beijing, the air monitoring data (PM2.5, SO2, NO2 and CO) from that period published by Chinese National Environmental Monitoring Center (CNEMC) was collected and analyzed with various statistical models. The cities within BTH area were clustered into three groups according to the geographical conditions, while the air pollutant concentrations of cities within a group sharing similar variation trends. The Granger causality test results indicate that significant causal relationships exist between the air pollutant data of Beijing and its surrounding cities (Baoding, Chengde, Tianjin and Zhangjiakou) for the reference period. Then, linear regression models were constructed to capture the interdependency among the multiple time series. It shows that the observed air pollutant concentrations in Beijing were well consistent with the model-fitted results. More importantly, further analysis suggests that the air pollutants in Beijing were strongly affected by regional transportation, as the local sources only contributed 17.88%, 27.12%, 14.63% and 31.36% of PM2.5, SO2, NO2 and CO concentrations, respectively. And the major foreign source for Beijing was from Southwest (Baoding) direction, account for more than 42% of all these air pollutants. Thus, by combining various statistical models, it may not only be able to quickly predict the air qualities of any cities on a regional scale, but also to evaluate the local and regional source contributions for a particular city. Key words: regional transportation, air pollution, Granger causality test, statistical models

  4. Seasonal variations and source estimation of saccharides in atmospheric particulate matter in Beijing, China.

    PubMed

    Liang, Linlin; Engling, Guenter; Du, Zhenyu; Cheng, Yuan; Duan, Fengkui; Liu, Xuyan; He, Kebin

    2016-05-01

    Saccharides are important constituents of atmospheric particulate matter (PM). In order to better understand the sources and seasonal variations of saccharides in aerosols in Beijing, China, saccharide composition was measured in ambient PM samples collected at an urban site in Beijing. The highest concentrations of total saccharides in Beijing were observed in autumn, while an episode with abnormal high total saccharide levels was observed from 15 to 23 June, 2011, due to extensive agricultural residue burning in northern China during the wheat harvest season. Compared to the other two categories of saccharides, sugars and sugar alcohols, anhydrosugars were the predominant saccharide group, indicating that biomass burning contributions to Beijing urban aerosol were significant. Ambient sugar and sugar alcohol levels in summer and autumn were higher than those in spring and winter, while they were more abundant in PM2.5 during winter time. Levoglucosan was the most abundant saccharide compound in both PM2.5 and PM10, the annual contributions of which to total measured saccharides in PM2.5 and PM10 were 61.5% and 54.1%, respectively. To further investigate the sources of the saccharides in ambient aerosols in Beijing, the PM10 datasets were subjected to positive matrix factorization (PMF) analysis. Based on the objective function to be minimized and the interpretable factors identified by PMF, six factors appeared to be optimal as to the probable origin of saccharides in the atmosphere in Beijing, including biomass burning, soil or dust, isoprene SOA and the direct release of airborne fungal spores and pollen. PMID:26921589

  5. Contamination status of hexachlorobenzene (HCB) in sandstorm depositions from Beijing and the origination region.

    PubMed

    Fu, S; Li, K; Yang, Z; Xu, X B

    2008-08-01

    In China, sandstorms play an important role in the long-range atmospheric transport and deposition of hexachlorobenzene (HCB). Concentrations of HCB in sandstorm depositions sampled from Beijing and the origination region were measured to reveal HCB levels during atmospheric transport. The results suggested a constant level of HCB during atmospheric transport. The values were close to environmental background values indicating that no potential source of HCB existed along the transport route. A tendency for HCB levels in Beijing to increase from north to east was also observed, which was probably due to the influence of wind speed and industrial zone distribution. PMID:18465068

  6. Estimation of Biomass Burning Influence on Air Pollution around Beijing from an Aerosol Retrieval Model

    PubMed Central

    Mukai, Sonoyo; Nakata, Makiko

    2014-01-01

    We investigate heavy haze episodes (with dense concentrations of atmospheric aerosols) occurring around Beijing in June, when serious air pollution was detected by both satellite and ground measurements. Aerosol retrieval is achieved by radiative transfer simulation in an Earth atmosphere model. We solve the radiative transfer problem in the case of haze episodes by successive order of scattering. We conclude that air pollution around Beijing in June is mainly due to increased emissions of anthropogenic aerosols and that carbonaceous aerosols from agriculture biomass burning in Southeast Asia also contribute to pollution. PMID:25250383

  7. Optic Disc - Fovea Angle: The Beijing Eye Study 2011

    PubMed Central

    Jonas, Rahul A.; Wang, Ya Xing; Yang, Hua; Li, Jian Jun; Xu, Liang; Panda-Jonas, Songhomitra; Jonas, Jost B.

    2015-01-01

    Purpose To determine the optic disc-fovea angle (defined as angle between the horizontal and the line between the optic disc center and the fovea) and to assess its relationships with ocular and systemic parameters. Methods The population-based cross-sectional Beijing Eye Study 2011 included 3468 individuals. A detailed ophthalmic examination was carried out. Using fundus photographs, we measured the disc-fovea angle. Results Readable fundus photographs were available for 6043 eyes of 3052 (88.0%) individuals with a mean age of 63.6±9.3 years (range: 50–91 years) and a mean axial length of 23.2±1.0 mm (range: 18.96–28.87 mm). Mean disc-fovea angle was 7.76 ± 3.63° (median: 7.65°; range: -6.3° to 28.9°). The mean inter-eye difference was 4.01 ± 2.94° (median: 3.49°; range: 0.00–22.3°). In multivariate analysis, larger disc-fovea angle was associated (regression coefficient r2: 0.08) with older age (P = 0.009; standardized regression coefficient beta: 0.05), thinner RNFL in the nasal superior sector (P<0.001; beta: -0.17), superior sector (P<0.001; beta: -0.10) and temporal superior sector (P<0.001; beta: -0.11) and thicker RNFL in the inferior sector (P<001; beta: 0.13), nasal inferior sector (P<001; beta: 0.13) and nasal sector (P = 0.007; beta: 0.06), higher prevalence of retinal vein occlusion (P = 0.02; beta: 0.04), and with larger cylindrical refractive error (P = 0.04; beta: 0.04). Conclusions The optic disc-fovea angle markedly influences the regional distribution of the RNFL thickness pattern. The disc-fovea angle may routinely be taken into account in the morphological glaucoma diagnosis and in the assessment of structure-function relationship in optic nerve diseases. Future studies may address potential associations between a larger disc-fovea angle and retinal vein occlusions and between the disc-fovea angle and the neuroretinal rim shape. PMID:26545259

  8. [Airborne fungal community composition in indoor environments in Beijing].

    PubMed

    Fang, Zhi-guo; Ouyang, Zhi-yun; Liu, Peng; Sun, Li; Wang, Xiao-yong

    2013-05-01

    Indoor environmental quality has significant effects on human health. It is reported that adults in China spent about 80%-90% of their time in indoor environments, and a number of physically handicapped people such as the elderly and infants stayed in the room even up to 95% of their total time. Moreover, air conditioner in indoor environments becomes more and more important in modern life, and a closed circulatory system can be formed among human body, room and air conditioner in indoor environments with an air conditioner, which can make the microbes such as bacteria, viruses and mold indoors propagate rapidly or abundantly. Therefore, studies on the microbial pollution in the air at places such as mall, classroom, office, and family home have been the research hotspots recently. In the present study, the community composition and concentration variation pattern of airborne fungi were investigated from Nov 2009 to Oct 2010 in 31 family homes with children in Beijing. Results showed that 24 generas of airborne fungi in family homes were identified from 225 isolates. The most common fungi were Penicillium, Cladosporium, Aspergillus, Alternaria and Phoma. The frequency of Penicillium, Cladosporium, Aspergillus, Alternaria and Monilia was much higher than those of other fungal genera in family home, and the frequency of Penicillium was more than 90%. As for the concentration percentage, airborne fungi with most high concentrations were Penicillium, Cladosporium, Aspergillus, No-sporing, and Alternaria, and totally accounted for more than 65.0%. Penicillium contributed to 32.2% of the total airborne fungi in family homes. In the 31 family homes selected, the fungal concentration in the air ranged from 62-3 498 CFU x m(-3), and the mean concentration was 837 CFU x m(-3). Seasonal variation pattern of total fungi, and Cladosporium, Aspergillus, Alternaria concentration was consistent, and the highest fungal concentration was observed in summer, followed by spring and

  9. Étude de la variation spatio-temporelle des paramètres physico-chimiques caractérisant la qualité des eaux d'une lagune côtière et ses zonations écologiques : cas de Moulay Bousselham, Maroc

    NASA Astrophysics Data System (ADS)

    Labbardi, Hanane; Ettahiri, Omar; Lazar, Said; Massik, Zakia; El Antri, Said

    2005-04-01

    Our interest is related to the hydrological characteristics of the Moulay Bousselham lagoon. Water samples were taken monthly from July 2001 to June 2002 in 15 stations distributed along the lagoon. The various measured hydrological parameters (temperature, salinity, suspended matter, chlorophyll a) showed significant monthly variations ( p<0.001), whereas spatially among all sampled stations, only the salinity showed significant variations. The variability analysis approached by the analysis of the normalized principal components combined with discriminate analysis showed very small inter-stations variability. Its percentage is 11% and 9% of the total variance during high and low tide, respectively. To cite this article: H. Labbardi et al., C. R. Geoscience 337 (2005).

  10. Comparative analysis of Mycobacterium tuberculosis Beijing strains isolated in three remote areas of Japan.

    PubMed

    Yokoyama, Eiji; Hachisu, Yushi; Iwamoto, Tomotada; Nakanishi, Noriko; Arikawa, Kentaro; Wada, Takayuki; Seto, Junji; Kishida, Kazunori

    2015-08-01

    A quantitative and qualitative comparison was carried out of Mycobacterium tuberculosis Beijing strains isolated in three remote areas of Japan. A total of 452 strains from Chiba Prefecture, 75 from Yamagata Prefecture, and 315 from Kobe City were analyzed for 24 loci by variable number of tandem repeats typing (24(Beijing)-VNTR). All strains were classified in six Beijing subgroups (B(SUB)), B1 to B5 and T, based on a minimum spanning tree reconstructed using data of a standard set of 15 VNTR loci. No significant difference was found in the distribution of strains in the B(SUB) in the three areas, with one exception due to a B5 outbreak in Yamagata, indicating no significant quantitative difference in the B(SUB) in the three areas (P<0.01, Chi-square test). In addition, when strains in each B(SUB) isolated in the three areas were mixed and standardized index of association (I(A)(s)) and variance (Φ(PT)) values were calculated, no significant qualitative difference in the B(SUB) in the three areas was found. These results suggested that the B(SUB) diverged prior to the introduction of M. tuberculosis Beijing strains into Japan. Differences in the distribution of strains in each B(SUB) between Japan and continental Asian countries suggested there had been genetic drift in the continental Asian countries in which B4 had been dominant. PMID:26096775

  11. Ambient particle characterization by single particle aerosol mass spectrometry in an urban area of Beijing

    NASA Astrophysics Data System (ADS)

    Li, Lei; Li, Mei; Huang, Zhengxu; Gao, Wei; Nian, Huiqing; Fu, Zhong; Gao, Jian; Chai, Fahe; Zhou, Zhen

    2014-09-01

    To investigate the composition and possible sources of aerosol particles in Beijing urban area, a single particle aerosol mass spectrometer (SPAMS) was deployed from April 22 to May 4, 2011. 510,341 particles out of 2,953,200 sized particles were characterized by SPAMS in combination with the ART-2a neural network algorithm. The particles were classified as rich-K (39.79%), carbonaceous species (32.7%), industry metal (19.2%), dust (5.7%), and rich-Na (1.76%). Industrial emissions related particles, rich-Fe, rich-Pb, and K-nitrate, were the major components of aerosol particles during haze periods, which were mainly from the steel plants and metal smelting processes around Beijing. Under stagnant meterological conditions, these regional emissions have a vital effect on haze formation. Organic carbon (OC) particles were attributed to biomass burning. NaK-EC was likely to come from local traffic emissions. Internally mixed organic and elemental carbon (OCEC) was found to be from possible sources of local traffic emission and biomass burning. It was found that coarse dust particles were mainly composed of four different types of dust particles, dust-Si, dust-Ca, dust-Al, and dust-Ti. It is the first time that SPAMS was used to study a dust storm in Beijing. Our results showed that SPAMS could be a powerful tool in the identification and apportionment of aerosol sources in Beijing, providing useful reference information for environmental control and management.

  12. Students' Perceptions of School Counselors: An Investigation of Two High Schools in Beijing, China

    ERIC Educational Resources Information Center

    Shi, Qi; Liu, Xi; Leuwerke, Wade

    2014-01-01

    This study sought to examine students' perceptions of their school counselors in two high schools in Beijing, China. Independent t tests found that female students rated school counselors' availability significantly higher than male students did. Also, students who had received prior counseling services rated counselors significantly higher in the…

  13. [Ability of typical greenery shrubs of Beijing to adsorb and arrest PM2.5 ].

    PubMed

    Liang, Dan; Wang, Bin; Wang, Yun-qi; Zhang, Hui-lan; Yang, Song-nan; Li, Ang

    2014-09-01

    Four typical types of green shrubs of Beijing (Euonymus japonicus, Buxus microphylla, Berberis thunbergii cv. atropurpurea, Taxus cuspidate cv. nana) were selected to study their capacities in adsorbing and arresting PM2.5 using both field observations and air chamber simulations. Concurrently, in order to analyze the pollution characteristics of Beijing in winter and spring, the PM2.5 concentrations of December 2012 to May 2013 were collected. Experimental results showed that: From the gas chamber experiments, the ability to adsorb and arrest PM2.5 was in the order of Berberis thunbergii cv. atropurpurea > Buxus microphylla > Taxus cuspidate cv. nana > Euonymus japonicus, mainly due to the differences in leaf characteristics; Outside measurement results showed that the ability to adsorb and arrest PM2.5 was ranked as Buxus microphylla > Berberis thunbergii cv. atropurpurea > Taxus cuspidate cv. nana > Euonymus japonicus. Chamber simulation and outdoor observation showed that Buxus microphylla and Berberis thunbergii cv. atropurpurea had strong ability to adsorb and arrest PM2.5; Meanwhile, the slight differences between the chamber simulation and outdoor observation results might be related to plant structure. Compared to tree species, the planting condition of shrub species was loose, and it greened quickly; By analyzing the Beijing PM2.5 concentration values in winter and spring, it was found that the PM2.5 concentration was particularly high in the winter of Beijing, and evergreen shrubs maintained the ability to adsorb and arrest PM2.5. PMID:25518685

  14. The evaluation of the value of soil erosion prevention on wetlands in Beijing

    NASA Astrophysics Data System (ADS)

    Zhou, Bo; Zhu, Lin; Zhao, Wenji; Liu, Hao

    2011-02-01

    Wetland is an important part of the ecological system. It has an important role in soil erosion prevention. Without the protection of wetland, soil erosion will cause two aspects physical loss, including 1) the waste land caused by soil degradation and desertification; 2) nutrient contents loss. This paper takes all wetland in Beijing as object. This research includes investigation and research on indexes of soil erosion prevention in Beijing wetland ecological system. Two aspects of reduction soil waste and prevent soil fertility are studied. Potential and actual soil erosion are calculated using GIS and universal soil erosion equation based on collected data, with the difference of the two amounts is the soil conservation quantify, which will be converted to economic value. Research results show the economic value of Beijing wetland in the soil erosion prevention is 4,962.56 million Yuan. The river and swamp have the highest value; meanwhile, the rural wetland's value of soil erosion resistance is more than in the urban area. Wetland has the extremely vital significance to keep a good ecological environment in Beijing.

  15. Policy Choice for Urban Low-carbon transportation in Beijing: Scenario Analysis Based on LEAP model

    NASA Astrophysics Data System (ADS)

    Zhang, Yu

    2016-04-01

    Beijing is a fast developing megacity with serious traffic problems, such as high energy consumption, high CO2 emission and traffic congestion. The coming 13th Five-Year Plan for Beijing economic and social development will focus on the low-carbon transportation policy to achieve the urban traffic sustainable development. In order to improve the feasibility of urban low-carbon transportation policies, this paper analyzes the future trends of CO2 emissions from transportation of Beijing. Firstly, five policies scenarios are developed according to the coming Beijing 13th Five-Year Plan, including the "Business As Usual (BAU)", the "Public Transportation Priority(PTP)", the "New Energy Vehicle(NEV)", the "Active Transportation(AT)", the "Private Car Regulation(PCR)" and the "Hybrid Policy(HP)". Then the Long-range Energy Alternatives Planning System(LEAP model) framework is adopted to estimate CO2 emission under given policies scenarios up to year 2020 and analyze the implications. The results demonstrate that the low-carbon transportation policies can reduce CO2 emission effectively. Specifically, the "Hybrid Policy(HP)" has the best performance. In terms of single policy effect, the "Private Car Regulation(PCR)" comes first followed by the "Public Transportation Priority(PTP)".

  16. Chemical composition and quantitative relationship between meteorological condition and fine particles in Beijing.

    PubMed

    Wang, Jing-Li; Zhang, Yuan-Hang; Shao, Min; Liu, Xu-Lin; Zeng, Li-Min; Cheng, Cong-Lan; Xu, Xiao-Feng

    2004-01-01

    The recent year's monitor results of Beijing indicated that the pollution level of fine particles PM2.5 showed an increasing trend. To understand pollution characteristics of PM2.5 and its relationship with the meteorological conditions in Beijing, a one-year monitoring of PM2.5 mass concentration and correspondent meteorological parameters was performed in Beijing in 2001. The PM2.5 levels in Beijing were very high, the annual average PM2.5 concentration in 2001 was 7 times of the National Ambient Air Quality Standards proposed by US EPA. The major chemical compositions were organics, sulfate, crustals and nitrate. It was found that the mass concentrations of PM2.5 were influenced by meteorological conditions. The correlation between the mass concentrations of PM2.5 and the relative humidity was found. And the correlation became closer at higher relative humidity. And the mass concentrations of PM2.5 were negtive-correlated to wind speeds, but the correlation between the mass concentration of PM2.5 and wind speed was not good at stronger wind. PMID:15559829

  17. [Mass size distributions and existing forms of sulfate and nitrate and atmospheric environment in Beijing].

    PubMed

    Mao, Hua-yun; Tian, Gang; Huang, Yu-hu; Li, Gang; Song, Guang-wu

    2011-05-01

    In order to understand the formations and the concentrations of the secondary sulfate and nitrate of PM10 in Beijing. From May 2008 to April 2009, MOUDI has been used to collect the PM10 samples in Beijing atmospheric environment and the ion chromatography has been used to analyze the inorganic water-soluble components of the PM10 samples. The results showed that the mass size distributions of soluble sulfate and nitrate of PM10 in Beijing were single-mode distribution and the peak rang was from 0.32 microm to 0.56 microm, and the primary formation ways was the chemical reaction in the gas phase. The results of partial correlation analysis indicated that the primary formations of sulfate and nitrate of PM10 in Beijing was (NH4)2SO4, NH4NO3, NaNO3, KNO3 and Ca(NO3)2. The mass concentration of secondary (NH4)2SO4 and NH4NO3 were (17.0 +/- 8.2) microg/m3 and (8.8 +/- 3.3) microg/m3 respectively, which accounted for (14.7 +/- 3.6)% and (7.6 +/- 2.2)% of PM10 respectively. The sum of them accounted for (22.3 +/- 4.3)% of PM10. PMID:21780574

  18. Are Boys Left Behind? The Evolution of the Gender Achievement Gap in Beijing's Middle Schools

    ERIC Educational Resources Information Center

    Lai, Fang

    2010-01-01

    Using one cohort of 7235 middle school students in Beijing, China, we examined the evolution of the gender achievement gap in middle school. Our study found a more significant female dominance than in U.S. studies: even though boys gradually caught up during middle school, especially in Math and Science, and the gender achievement gap decreased…

  19. Markets Hidden on Thoroughfares: The Social Construction of Economic Informality/Illegality in Beijing's Zhongguancun, China

    ERIC Educational Resources Information Center

    Chang, Ho-Jun

    2009-01-01

    This dissertation deals with the tense relation between the visibility of unauthorized economic practices and the invisibility of law in Zhongguancun (ZGC) Beijing, a Chinese information technology (IT) industry center dubbed "China's Silicon Valley." This dissertation ethnographically examines the double process of extra-legal/illegal economic…

  20. Economic evaluation of health losses from air pollution in Beijing, China.

    PubMed

    Zhao, Xiaoli; Yu, Xueying; Wang, Ying; Fan, Chunyang

    2016-06-01

    Aggravated air pollution in Beijing, China has caused serious health concern. This paper comprehensively evaluates the health losses from illness and premature death caused by air pollution in monetary terms. We use the concentration of PM10 as an indicator of the pollution since it constitutes the primary pollutant in Beijing. By our estimation, air pollution in Beijing caused a health loss equivalent to Ұ583.02 million or 0.03 % of its GDP. Most of the losses took the form of depreciation in human capital that resulted from premature death. The losses from premature deaths were most salient for people of either old or young ages, with the former group suffering from the highest mortality rates and the latter group the highest per capital losses of human capitals from premature death. Policies that target on PM10 emission reduction, urban vegetation expansion, and protection of vulnerable groups are all proposed as possible solutions to air pollution risks in Beijing. PMID:26944425

  1. Origin and primary dispersal of the Mycobacterium tuberculosis Beijing genotype: Clues from human phylogeography

    PubMed Central

    Mokrousov, Igor; Ly, Ho Minh; Otten, Tatiana; Lan, Nguyen Ngoc; Vyshnevskyi, Boris; Hoffner, Sven; Narvskaya, Olga

    2005-01-01

    We suggest that the evolution of the population structure of microbial pathogens is influenced by that of modern humans. Consequently, the timing of hallmark changes in bacterial genomes within the last 100,000 yr may be attempted by comparison with relevant human migrations. Here, we used a lineage within Mycobacterium tuberculosis, a Beijing genotype, as a model and compared its phylogeography with human demography and Y chromosome-based phylogeography. We hypothesize that two key events shaped the early history of the Beijing genotype: (1) its Upper Palaeolithic origin in the Homo sapiens sapiens K-M9 cluster in Central Asia, and (2) primary Neolithic dispersal of the secondary Beijing NTF::IS6110 lineage by Proto-Sino-Tibetan farmers within east Asia (human O-M214/M122 haplogroup). The independent introductions of the Beijing strains from east Asia to northern Eurasia and South Africa were likely historically recent, whereas their differential dissemination within these areas has been influenced by demographic and climatic factors. PMID:16169923

  2. The State, Citizenship Education, and International Events in a Global Age: The 2008 Beijing Olympic Games

    ERIC Educational Resources Information Center

    Law, Wing-Wah

    2010-01-01

    With reference to the 2008 Beijing Olympic Games, this article shows how the Chinese state continues to be a key actor in defining citizenship and citizenship education by promoting nationalism and nation-specific elements of citizenship education while linking its people to an increasingly interconnected world. In particular, this study examines…

  3. [Evaluation on the Effectiveness of Vehicle Exhaust Emission Control Measures During the APEC Conference in Beijing].

    PubMed

    Fan, Shou-bin; Tian, Ling-di; Zhang, Dong-xu; Guo, Jin-jin

    2016-01-15

    Vehicle emission is one of the primary factors affecting the quality of atmospheric environment in Beijing. In order to improve the air quality during APEC conference, strict control measures including vehicle emission control were taken in Beijing during APEC meeting. Based on the activity level data of traffic volume, vehicle speed and vehicle types, the inventory of motor vehicle emissions in Beijing was developed following bottom-up methodology to assess the effectiveness of the control measures. The results showed that the traffic volume of Beijing road network during the APEC meeting decreased significantly, the vehicle speed increased obviously, and the largest decline of traffic volume was car. CO, NOx, HC and PM emissions of vehicle exhaust were reduced by 15.1%, 22.4%, 18.4% and 21.8% for freeways, 29.9%, 36.4%, 32.7% and 35.8% for major arterial, 35.7%, 41.7%, 38.4% and 41.2% for minor arterial, 40.8%, 46.5%, 43.1% and 46.0% for collectors, respectively. The vehicles exhaust emissions inventory before and during APEC conference was developed based on bottom-up emissions inventory method. The results indicated that CO, NOx, HC and PM emissions of vehicle exhaust were reduced by 37.5%, 43.4%, 39.9% and 42.9% in the study area, respectively. PMID:27078943

  4. The Initiation of Early Childhood Inclusion in China: A Case Study from Beijing

    ERIC Educational Resources Information Center

    Hu, Bi Ying; Roberts, Sherron Killingsworth; Wang, Yanhua; Zhao, Hongmei

    2011-01-01

    The national policies of the Chinese government regarding preschool inclusion are emerging to promote the well-being of all children, particularly children with disabilities in natural environments such as regular preschools or in homes. Following the global trend towards inclusive education, preschools in Beijing are gradually implementing both…

  5. ELEVATED PLUME TRANSPORT AND DIFFUSION: 20 TO 150 KM DOWNWIND OF BEIJING, PRC

    EPA Science Inventory

    Three mobile continuous and an array of fixed sequential syringe analyzers samplers were used to measure plume dispersion rates of SF6 released from a 300 m tower in Beijing during strong, steady winds with neutral conditions. he plume trajectories over the flat, open terrain dow...

  6. Use of homing pigeons as biomonitors of atmospheric metal concentrations in Beijing and Guangzhou, China.

    PubMed

    Cui, Jia; Halbrook, Richard S; Zang, Shuying; You, Jing

    2016-04-01

    Biomonitoring provides direct evidence of the bioavailability and accumulation of toxic elements in the environment and in the current study, homing pigeons were used as a biomonitor of atmospheric pollution in Beijing and Guangzhou, China. Cadmium (Cd), lead (Pb), and mercury (Hg) concentrations were measured in lung, kidney, and liver tissues of 25 homing pigeons collected from Beijing (n = 15) and Guangzhou (n = 10). Cadmium concentrations in all tissue and lung Pb concentrations were significantly greater in pigeons collected from Guangzhou compared to those collected from Beijing. Lung Cd and Pb concentrations corresponded to differences in ambient air concentrations between the two cities, suggesting that homing pigeons are valuable biomonitors of atmospheric metal contamination. Liver and kidney Hg concentrations were significantly greater in pigeons collected from Beijing compared to those collected from Guangzhou, while Hg concentrations in lung tissue were not significantly different. Results of the current study support a conclusion that homing pigeons provide valuable data for evaluating exposure and potential effects to environmental metal concentrations. PMID:26703383

  7. Validation of the Autism Spectrum Screening Questionnaire, Mandarin Chinese Version (CH-ASSQ) in Beijing, China

    ERIC Educational Resources Information Center

    Guo, Yan-Qing; Tang, Yilang; Rice, Catherine; Lee, Li-Ching; Wang, Yu-Feng; Cubells, Joseph F.

    2011-01-01

    Background: This study screened children in Beijing, China, in order to establish the validity of a Mandarin Chinese translation of the ASSQ. Methods: We recruited children diagnosed with autism spectrum disorders (ASDs), attention deficit/hyperactivity disorder (ADHD), childhood-onset schizophrenia (COS) (DSM-IV diagnoses made independently by…

  8. Low induction of proinflammatory cytokines parallels evolutionary success of modern strains within the Mycobacterium tuberculosis Beijing genotype.

    PubMed

    van Laarhoven, Arjan; Mandemakers, Jornt J; Kleinnijenhuis, Johanneke; Enaimi, Mimount; Lachmandas, Ekta; Joosten, Leo A B; Ottenhoff, Tom H M; Netea, Mihai G; van Soolingen, Dick; van Crevel, Reinout

    2013-10-01

    One of the most widespread clades of Mycobacterium tuberculosis worldwide, the Beijing genotype family, consists of ancient (atypical) and modern (typical) strains. Modern Beijing strains outcompete ancient strains in terms of prevalence, while reserving a higher degree of genetic conservation. We hypothesize that their selective advantage lies in eliciting a different host immune response. Bead-disrupted lysates of a collection of different M. tuberculosis strains of the modern (n = 7) or ancient (n = 7) Beijing genotype, as well as the Euro-American lineage (n = 6), were used for induction of ex vivo cytokine production in peripheral blood mononuclear cells (PBMCs) from 10 healthy individuals. Hierarchical clustering and multivariate regression analyses were used to study possible differences in production of nine cytokines. Modern and ancient M. tuberculosis Beijing genotypes induced different cytokine signatures. Overall induction of interleukin-1β (IL-1β), gamma interferon (IFN-γ), and IL-22 was 38 to 40% lower after stimulation with modern Beijing strains (corrected P values of <0.0001, 0.0288, and 0.0002, respectively). Euro-American reactivation strains induced 2-fold more TNF-α production than both types of Beijing strains. The observed differences in cytokine induction point to a reduction in proinflammatory cytokine response as a possible contributing factor to the evolutionary success of modern Beijing strains. PMID:23897611

  9. Research on Beijing human settlement in district level by GIS spatial analyzing

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaojun; Yin, Weihong; Dong, Suocheng; Guo, Hongshi

    2009-08-01

    This paper mainly focuses on the human settlement of livable city appraisal system to research the evaluation criteria, using Spatial Analyzing in Arcinfo, to unify the objective evaluation system, to conduct the analysis research from the spatial angle to Beijing residential environment healthy, by the subjective and objective aspects, there has conducted the spatial analysis research on the urban residential environment. The research indicated that:1) Beijing urban district residential environment healthy satisfaction degree level still permissible, has the obvious spatial autocorrelation characteristic. The satisfaction degree of the spatial difference research to indicate that, the satisfaction degree overall existence by take the urban center as the zero point to the periphery emission, the section presents "the saddle" characteristic, has the satisfaction degree nearby the transportation node "concave" region, simultaneously, some islet existence, also causes to the spatial distribution of the livable city satisfaction degree to be more complex; 2) uses the Beijing Environmental protection Bureau issue 2000-2006 year correlation data, carries on the objective evaluation using the factor analysis method to Beijing environment healthy in recent years, discovered atmospheric and the noise pollution does not present the rule change tendency; 3) the residential environment healthy system will divide into atmospheric, the water, the noise and the solid reject four sub-systems, will carry on the subjective and objective appraisal to Beijing the synthesis contrast analysis, north city is higher than western city regarding the air pollution appraisal. In the central city Xicheng District and Chongwen district's inhabitant has the enhancement regarding the air pollution appraisal, but Xuanwu district and Dongcheng district's air pollution condition still had certain disparity from the public satisfaction; The noise appraisal aspect, east city is higher than western

  10. High-resolution MIRU-VNTRs typing reveals the unique nature of Mycobacterium tuberculosis Beijing genotype in Okinawa, Japan.

    PubMed

    Millet, Julie; Miyagi-Shiohira, Chika; Yamane, Nobuhisa; Mokrousov, Igor; Rastogi, Nalin

    2012-06-01

    Mycobacterium tuberculosis Beijing lineage is highly prevalent in Japan. The aim of the present study was to describe the population structure of the Beijing lineage in this country based on 12-, 15-, and 21-loci MIRU-VNTR genotyping schemes. The MIRU-VNTR patterns of Beijing strains from Okinawa, Ryukyu Islands were compared to those recently published from the Osaka-Kobe megalopolis of the main island of Japan, Honshu (Wada et al., 2009). We also compared proportions of "modern/typical" vs. "ancient/atypical" Beijing strains as defined by structure of the NTF locus. Contrarily to the 12-loci Minimum Spanning Tree (MST), the 15- and 21-loci trees allowed the distinction of two groups of strains in Okinawa. A 12-loci MIRU-VNTR pattern (223325173533) corresponding to MIRU international type MIT17 was identified as the most prevalent Beijing genotype in Japan. In the SITVIT2 database, this pattern was found to be disseminated worldwide and corresponded to the most widely distributed Beijing profile in East Asia and former USSR countries. A comparison of 15- and 21-loci MIRU-VNTR patterns showed that two loci (QUB-4156 and Mtub21) were most polymorphic in our study, and could be potential candidates to distinguish between NTF locus based subclassification of Beijing strains. High-resolution VNTR typing using 15- and 21-loci underlined an evolutionarily distinct "ancient/atypical" subpopulation of the Beijing genotype in Okinawa as well as a subgroup of strains closely related to "modern/typical" Beijing strains observed in Osaka/Kobe. PMID:21723420

  11. Rapid and simple identification of Beijing genotype strain of Mycobacterium tuberculosis using a loop-mediated isothermal amplification assay.

    PubMed

    Nagai, Yuhki; Iwade, Yoshito; Nakano, Manabu; Akachi, Shigehiro; Kobayashi, Takashi; Nishinaka, Takamichi

    2016-07-01

    Beijing genotype strains of Mycobacterium tuberculosis are geographically widespread and pose a notorious public health problem, these strains causing outbreaks of multidrug-resistant tuberculosis (TB); some studies have reported an association with drug resistance. Because the prevalence of Beijing strain has a substantial impact on TB control programs, the availability of a rapid and reliable method for detecting these strains is important for epidemiological monitoring of their circulation. The main methods currently used to identify Beijing genotype strains are IS6110 DNA fingerprinting, spoligotyping and PCR to detect specific deletions such as region of difference (RD)207. More recently, multiplex PCR assay using a Beijing-specific single nucleotide polymorphism (SNP) has been developed for detecting Beijing lineage strains. However, these methods are time-consuming and technically demanding. In the present study, a loop-mediated isothermal amplification (LAMP) assay that allows specific identification of Beijing genotype strain was developed. This Beijing genotype strain-identifying LAMP assay was performed 214 clinical isolates and the results compared with those of conventional PCR that targeted RD207 and Rv0679c-targreting multiplex PCR for Beijing lineage identification. LAMP assay showed 100% sensitivity and specificity compared with RD207-PCR. Furthermore, the sensitivity and specificity were 99.3% and 100%, respectively, compared with Rv0679c-multiplex PCR. This LAMP assay could be used routinely in local laboratories to monitor the prevalence of the Beijing genotype strain and thereby used to help control the spread of these potentially highly virulent and drug resistant strains. PMID:27213686

  12. Disclosure of Selective Advantages in the “modern” Sublineage of the Mycobacterium tuberculosis Beijing Genotype Family by Quantitative Proteomics*

    PubMed Central

    de Keijzer, Jeroen; de Haas, Petra E.; de Ru, Arnoud H.; van Veelen, Peter A.; van Soolingen, Dick

    2014-01-01

    The Mycobacterium tuberculosis Beijing genotype, consisting of the more ancient (atypical) and modern (typical) emerging sublineage, is one of the most prevalent and genetically conserved genotype families and has often been associated with multidrug resistance. In this study, we employed a 2D-LC-FTICR MS approach, combined with dimethylation of tryptic peptides, to systematically compare protein abundance levels of ancient and modern Beijing strains and identify differences that could be associated with successful spread of the modern sublineage. The data is available via ProteomeXchange using the identifier PXD000931. Despite the highly uniform protein abundance ratios in both sublineages, we identified four proteins as differentially regulated between both sublineages, which could explain the apparent increased adaptation of the modern Beijing strains. These proteins are; Rv0450c/MmpL4, Rv1269c, Rv3137, and Rv3283/sseA. Transcriptional and functional analysis of these proteins in a large cohort of 29 Beijing strains showed that the mRNA levels of Rv0450c/MmpL4 are significantly higher in modern Beijing strains, whereas we also provide evidence that Rv3283/sseA is less abundant in the modern Beijing sublineage. Our findings provide a possible explanation for the increased virulence and success of the modern Beijing sublineage. In addition, in the established dataset of 1817 proteins, we demonstrate the pre-existence of several, possibly unique, antibiotic efflux pumps in the proteome of the Beijing strains. This may reflect an increased ability of Beijing strains to escape exposure to antituberculosis drugs. PMID:25022876

  13. Atmospheric particulate mercury in the megacity Beijing: Efficiency of mitigation measures and assessment of health effects

    NASA Astrophysics Data System (ADS)

    Schleicher, N. J.; Schäfer, J.; Chen, Y.; Blanc, G.; Chen, Y.; Chai, F.; Cen, K.; Norra, S.

    2016-01-01

    Atmospheric particulate mercury (HgP) was studied before, during, and after the Olympic Summer Games in Beijing, China, in August 2008 in order to investigate the efficiency of the emission control measures implemented by the Chinese Government. These source control measures comprised traffic reductions, increase in public transportation, planting of vegetation, establishment of parks, building freeze at construction sites, cleaner production techniques for industries and industry closures in Beijing and also in the surrounding areas. Strictest measures including the "odd-even ban" to halve the vehicle volume were enforced from the 20th of July to the 20th of September 2008. The Olympic period provided the unique opportunity to investigate the efficiency of these comprehensive actions implemented in order to reduce air pollution on a large scale. Therefore, the sampling period covered summer (August, September) and winter (December and January) samples over several years from December 2005 to September 2013. Average HgP concentrations in total suspended particulates (TSP) sampled in August 2008 were 81 ± 39 pg/m3 while TSP mass concentrations were 93 ± 49 μg/m3. This equals a reduction by about 63% for TSP mass and 65% for HgP, respectively, compared to the previous two years demonstrating the short-term success of the measures. However, after the Olympic Games, HgP concentrations increased again to pre-Olympic levels in August 2009 while values in August 2010 decreased again by 30%. Moreover, winter samples, which were 2- to 11-fold higher than corresponding August values, showed decreasing concentrations over the years indicating a long-term improvement of HgP pollution in Beijing. However, regarding adverse health effects, comparisons with soil guideline values and studies from other cities highlighted that HgP concentrations in TSP remained high in Beijing despite respective control measures. Consequently, future mitigation measures need to be tailored more

  14. Size segregated water uptake of the urban submicrometer aerosol in Beijing

    NASA Astrophysics Data System (ADS)

    Massling, A.; Stock, M.; Wehner, B.; Wu, Z. J.; Hu, M.; Brüggemann, E.; Gnauk, T.; Herrmann, H.; Wiedensohler, A.

    Physical and chemical properties of submicrometer aerosol particles were measured in summer 2004 (June/July) and winter 2005 (January/February) in Beijing, Peoples Republic of China, using a Twin-Differential Mobility Particle Sizer (T-DMPS), a Hygroscopicity-Tandem Differential Mobility Analyzer (H-TDMA), and a Micro Orifice Uniform Deposit Impactor (MOUDI). Particle number-size distributions were measured in the diameter range Dp = 3-800 nm and hygroscopic properties were determined at initial dry particle diameters of Dp j ( j = 30, 50, 80, 150, 250, and 350 nm) at a relative humidity (RH) of 90%. Hygroscopic properties were compared with chemical analyses of aerosol samples taken with the MOUDI. Based on the hygroscopicity data, the total hygroscopic particle volume was modeled, including dependence on dry particle size, season and level of pollution using a simple approach. Overall, the chemical analysis showed ammonium sulfate to be the major inorganic component of the urban submicrometer aerosol in Beijing along with relatively high fractions of elemental carbon (10-25%) and organic matter (15-60%) depending on particle size and season. The hygroscopic growth distributions (H-TDMA) subdivided the aerosol population into three different groups of particles with varying growth factors depending on dry particle size, namely nearly hydrophobic (growth factor = 0.96-1.07), less hygroscopic (1.06-1.29) and more hygroscopic (1.26-1.62). Hydrophobic particle fractions indicating freshly emitted soot/carbonaceous particles varied between 10 and 32% depending on dry particle size and season. During heavily polluted times, a decreasing number of hydrophobic particle fractions indicated that the urban submicrometer aerosol in Beijing was highly influenced by more aged aerosol transported from the industrial regions around Beijing containing sulfate as a major component. Based on model calculations, the urban submicrometer aerosol in Beijing showed strong compositional

  15. Modeling the feedback between aerosol and boundary layer processes: a case study in Beijing, China.

    PubMed

    Miao, Yucong; Liu, Shuhua; Zheng, Yijia; Wang, Shu

    2016-02-01

    Rapid development has led to frequent haze in Beijing. With mountains and sea surrounding Beijing, the pollution is found to be influenced by the mountain-plain breeze and sea-land breeze in complex ways. Meanwhile, the presence of aerosols may affect the surface energy balance and impact these boundary layer (BL) processes. The effects of BL processes on aerosol pollution and the feedback between aerosol and BL processes are not yet clearly understood. Thus, the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) is used to investigate the possible effects and feedbacks during a haze episode on 23 September 2011. Influenced by the onshore prevailing wind, sea-breeze, and upslope breeze, about 45% of surface particulate matter (PM)2.5 in Beijing are found to be contributed by its neighbor cities through regional transport. In the afternoon, the development of upslope breeze suppresses the growth of BL in Beijing by imposing a relatively low thermal stable layer above the BL, which exacerbates the pollution. Two kinds of feedback during the daytime are revealed as follows: (1) as the aerosols absorb and scatter the solar radiation, the surface net radiation and sensible heat flux are decreased, while BL temperature is increased, resulting in a more stable and shallower BL, which leads to a higher surface PM2.5 concentration in the morning and (2) in the afternoon, as the presence of aerosols increases the BL temperature over plains, the upslope breeze is weakened, and the boundary layer height (BLH) over Beijing is heightened, resulting in the decrease of the surface PM2.5 concentration there. PMID:26490909

  16. Monitoring and analyzing surface subsidence based on SBAS-InSAR in Beijing region, China

    NASA Astrophysics Data System (ADS)

    Zhou, L.; Guo, J. M.; Li, X.

    2015-12-01

    Surface subsidence is the main regional environmental geological disaster in plain area in China. The rapid growth of population, the over-exploitation of groundwater and the rapid development of urbanization impacts the occurrence and development of surface subsidence to some extent. The city of Beijing, located in the Beijing Plain, is one of international metropolis in China that experiences the severe surface subsidence. Because of conventional measurement methods with low spatial resolution, differential interferometric synthetic aperture radar(D-InSAR) is susceptible to signal decorrelation and atmospheric delay, persistent scatterer interferometric synthetic aperture radar(PS-InSAR) is based on a large number of SAR images, but small baseline subset interferometric synthetic aperture radar (SBASInSAR) only needs a small number of images and performs better than PS-InSAR for obtaining nonlinear deformation information, in this paper, SBAS-InSAR was used to obtain the high resolution surface subsidence information in Beijing region, China. A spatial-temporal analysis of the surface subsidence in Beijing region during the years of 2007- 2010 was performed utilizing eighteen C-band ENVISAT ASAR images (from August 1, 2007 to September 29, 2010). The results show that subsidence in Beijing region is severe uneven, subsidence funnels appear in Changping District, Shunyi District, Tongzhou District, Daxing District, etc., and many subsidence funnels are interconnected and have an eastward expansion trend; during the period of 2007 to 2010, the subsidence velocities are in the range of -158.5 mm/year to 12.4 mm/year and the maximum subsidence of subsidence center is over 400 mm; surface subsidence is influenced by groundwater exploitation and urbanization significantly.

  17. Spatiotemporal Pattern Analysis of Scarlet Fever Incidence in Beijing, China, 2005–2014

    PubMed Central

    Mahara, Gehendra; Wang, Chao; Huo, Da; Xu, Qin; Huang, Fangfang; Tao, Lixin; Guo, Jin; Cao, Kai; Long, Liu; Chhetri, Jagadish K.; Gao, Qi; Wang, Wei; Wang, Quanyi; Guo, Xiuhua

    2016-01-01

    Objective: To probe the spatiotemporal patterns of the incidence of scarlet fever in Beijing, China, from 2005 to 2014. Methods: A spatiotemporal analysis was conducted at the district/county level in the Beijing region based on the reported cases of scarlet fever during the study period. Moran’s autocorrelation coefficient was used to examine the spatial autocorrelation of scarlet fever, whereas the Getis-Ord Gi* statistic was used to determine the hotspot incidence of scarlet fever. Likewise, the space-time scan statistic was used to detect the space-time clusters, including the relative risk of scarlet fever incidence across all settings. Results: A total of 26,860 scarlet fever cases were reported in Beijing during the study period (2005–2014). The average annual incidence of scarlet fever was 14.25 per 100,000 population (range, 6.76 to 32.03 per 100,000). The incidence among males was higher than that among females, and more than two-thirds of scarlet fever cases (83.8%) were among children 3–8 years old. The seasonal incidence peaks occurred from March to July. A higher relative risk area was mainly in the city and urban districts of Beijing. The most likely space-time clusters and secondary clusters were detected to be diversely distributed in every study year. Conclusions: The spatiotemporal patterns of scarlet fever were relatively unsteady in Beijing from 2005 to 2014. The at-risk population was mainly scattered in urban settings and dense districts with high population, indicating a positive relationship between population density and increased risk of scarlet fever exposure. Children under 15 years of age were the most susceptible to scarlet fever. PMID:26784213

  18. A comparison analysis of chemical composition of aerosols in the dust and non-dust periods in Beijing

    NASA Astrophysics Data System (ADS)

    Zhang, Renjian; Xu, Yongfu; Han, Zhiwei

    2004-04-01

    Dust events occurred frequently in Beijing in recent years. In this work, 120 aerosol samples were collected in two typical dust events (21 22 March and 15 May) and a non-dust period in Beijing from March to May 2001. Samples were analyzed for major elemental components by the Proton Induced X-ray Emission (PIXE) method. Results show that the enrichment factors of crustal elements such as Mg, Al, and Ti had little differences between the dust period and the non-dust period in Beijing, while the enrichment factors of other elements that have a relation to anthropogenic emissions were very low during the dust period. The results derived by using multivariate factor analysis from the observation data show that the sources such as soil dust, industry, and fuel combustion were among the major contributors to the particles in Beijing.

  19. The air quality forecast in Beijing with Community Multi-scale Air Quality Modeling (CMAQ) System: model evaluation and improvement

    NASA Astrophysics Data System (ADS)

    Wu, Q.

    2013-12-01

    The MM5-SMOKE-CMAQ model system, which is developed by the United States Environmental Protection Agency(U.S. EPA) as the Models-3 system, has been used for the daily air quality forecast in the Beijing Municipal Environmental Monitoring Center(Beijing MEMC), as a part of the Ensemble Air Quality Forecast System for Beijing(EMS-Beijing) since the Olympic Games year 2008. In this study, we collect the daily forecast results of the CMAQ model in the whole year 2010 for the model evaluation. The results show that the model play a good model performance in most days but underestimate obviously in some air pollution episode. A typical air pollution episode from 11st - 20th January 2010 was chosen, which the air pollution index(API) of particulate matter (PM10) observed by Beijing MEMC reaches to 180 while the prediction of PM10-API is about 100. Taking in account all stations in Beijing, including urban and suburban stations, three numerical methods are used for model improvement: firstly, enhance the inner domain with 4km grids, the coverage from only Beijing to the area including its surrounding cities; secondly, update the Beijing stationary area emission inventory, from statistical county-level to village-town level, that would provide more detail spatial informance for area emissions; thirdly, add some industrial points emission in Beijing's surrounding cities, the latter two are both the improvement of emission. As the result, the peak of the nine national standard stations averaged PM10-API, which is simulated by CMAQ as daily hindcast PM10-API, reach to 160 and much near to the observation. The new results show better model performance, which the correlation coefficent is 0.93 in national standard stations average and 0.84 in all stations, the relative error is 15.7% in national standard stations averaged and 27% in all stations. The time series of 9 national standard in Beijing urban The scatter diagram of all stations in Beijing, the red is the forecast and

  20. Primary sources and secondary formation of organic aerosols in Beijing, China.

    PubMed

    Guo, Song; Hu, Min; Guo, Qingfeng; Zhang, Xin; Zheng, Mei; Zheng, Jun; Chang, Chih Chung; Schauer, James J; Zhang, Renyi

    2012-09-18

    Ambient aerosol samples were collected at an urban site and an upwind rural site of Beijing during the CAREBEIJING-2008 (Campaigns of Air quality REsearch in BEIJING and surrounding region) summer field campaign. Contributions of primary particles and secondary organic aerosols (SOA) were estimated by chemical mass balance (CMB) modeling and tracer-yield method. The apportioned primary and secondary sources explain 73.8% ± 9.7% and 79.6% ± 10.1% of the measured OC at the urban and rural sites, respectively. Secondary organic carbon (SOC) contributes to 32.5 ± 15.9% of the organic carbon (OC) at the urban site, with 17.4 ± 7.6% from toluene, 9.7 ± 5.4% from isoprene, 5.1 ± 2.0% from α-pinene, and 2.3 ± 1.7% from β-caryophyllene. At the rural site, the secondary sources are responsible for 38.4 ± 14.4% of the OC, with the contributions of 17.3 ± 6.9%, 13.9 ± 9.1%, 5.6 ± 1.9%, and 1.7 ± 1.0% from toluene, isoprene, α-pinene, and β-caryophyllene, respectively. Compared with other regions in the world, SOA in Beijing is less aged, but the concentrations are much higher; between the sites, SOA is more aged and affected by regional transport at the urban site. The high SOA loading in Beijing is probably attributed to the high regional SOC background (~2 μg m(-3)). The toluene SOC concentration is high and comparable at the two sites, implying that some anthropogenic components, at least toluene SOA, are widespread in Beijing and represents a major factor in affecting the regional air quality. The aerosol gaseous precursor concentrations and temperature correlate well with SOA, both affecting SOA formation. The significant SOA enhancement with increasing water uptake and acidification indicates that the aqueous-phase reactions are largely responsible SOA formation in Beijing. PMID:22486583

  1. Aerosol Properties under Air Quality Control Measures of APEC 2014 in Beijing

    NASA Astrophysics Data System (ADS)

    Chen, X.; Xu, H.; Lv, Y.; Xie, Y.; Li, K.; Li, Z.; Li, D.; Ma, Y.; Mei, X.

    2015-12-01

    Because the economic and society were developing fast in the middle of last century, Los Angeles and London both were polluted by photochemical smog, which massacred thousands of people. Now, many regions are often covered by heavy haze in those large developing countries, especially in China and India. The Asia-Pacific Economic Cooperation (APEC) was held in Beijing during 5-11 November 2014. Beijing, Hebei, Tianjin, Shandong, Shanxi, Inner Mongolia reduced air pollution emissions for the APEC 2014 meeting held in Beijing. Only in Hebei province, there were 1028 factories stopped or restricted and 881 construction sites stopped. Half of the cars were prohibited driving even in the Zibo city which is 400 km far from Beijing. For scientific aims, these control measures were indeed a huge and uncommon atmospheric experiment led by the government. During the experiment, what did the "APEC Blue" mean? We analyzed aerosol properties with the data of an AERONET site in Beijing which is located 500m far from the main reception hall of APEC 2014. The Cimel solar photometers can give a series parameters of aerosol and water vapor. In this paper, we used CE318 solar photometer which is the main instrument of NASA AERONET. The CE318 of RADI belongs to the Chinese SONET (Sun-sky radiometer Observation NETwork) too. We analyzed the total, coarse and fine Aerosol Optical Depth (AOD), Fine-Mode Fraction (FMF) and Ångström exponent, Size Distribution and Real Refractive Index. In conclusion, the aerosol properties were analysed with the measurements of a sun photometer. During the APEC 2014, AOD decreased obviously with a 0.27 mean value compared with the annual mean 0.7. Around Beijing, the southern is polluted emission area including the cross part of Shandong, Shanxi, Hebei, Henan four provinces, and the northern is clean for less fine mode particles emission in the large Inner Mongolia province. In fact, during the APEC 2014, the weather condition was not good for the

  2. Tuberculous Spondylitis in Russia and Prominent Role of Multidrug-Resistant Clone Mycobacterium tuberculosis Beijing B0/W148

    PubMed Central

    Solovieva, Natalia; Mushkin, Alexander; Manicheva, Olga; Vishnevsky, Boris; Zhuravlev, Viacheslav; Narvskaya, Olga

    2015-01-01

    Extrapulmonary and, in particular, spinal tuberculosis (TB) constitutes a minor but significant part of the total TB incidence. In spite of this, almost no studies on the genetic diversity and drug resistance of Mycobacterium tuberculosis isolates from spinal TB patients have been published to date. Here, we report results of the first Russian and globally largest molecular study of M. tuberculosis isolates recovered from patients with tuberculous spondylitis (TBS). The majority of 107 isolates were assigned to the Beijing genotype (n = 80); the other main families were T (n = 11), Ural (n = 7), and LAM (n = 4). Multidrug resistance (MDR) was more frequently found among Beijing (90.5%) and, intriguingly, Ural (71.4%) isolates than other genotypes (5%; P < 0.001). The extremely drug-resistant (XDR) phenotype was exclusively found in the Beijing isolates (n = 7). A notable prevalence of the rpoB531 and katG315 mutations in Beijing strains that were similarly high in both TBS (this study) and published pulmonary TB (PTB) samples from Russia shows that TBS and PTB Beijing strains follow the same paradigm of acquisition of rifampin (RIF) and isoniazid (INH) resistance. The 24-locus mycobacterial interspersed repetitive unit–variable-number tandem-repeat (MIRU-VNTR) subtyping of 80 Beijing isolates further discriminated them into 24 types (Hunter Gaston index [HGI] = 0.83); types 100-32 and 94-32 represented the largest groups. A genotype of Russian successful clone B0/W148 was identified in 30 of 80 Beijing isolates. In conclusion, this study highlighted a crucial impact of the Beijing genotype and the especially prominent role of its MDR-associated successful clone B0/W148 cluster in the development of spinal MDR-TB in Russian patients. PMID:25645851

  3. Spatial and Temporal Variations of Aerosols Around Beijing in the Summer 2006: Model Evaluation and Source Apportionment

    SciTech Connect

    Matsui, Hitoshi; Koike, Makoto; Kondo, Yutaka; Takegawa, Nobuyuki; Kita, K.; Miyazaki, Y.; Hu, M.; Chang, S-Y; Blake, D. R.; Fast, Jerome D.; Zaveri, Rahul A.; Streets, D. G.; Zhang, Q.; Zhou, T.

    2009-08-15

    Regional aerosol model calculations were made using the WRF-CMAQ and WRF-chem models to study spatial and temporal variations of aerosols around Beijing, China, in August and September 2006 when the CAREBEIJING-2006 campaign was conducted. Model calculations were compared with in-situ observations made at the urban site in Beijing and suburb site in Yufa, which is 50 km to the south of Beijing. In general, the two model calculations reproduced features of temporal variations of meteorological parameters and concentrations of elemental carbon (EC) and inorganic aerosols (sulfate, ammonium, and nitrate). Spatial distributions of aerosol optical depth (AOD) obtained by the MODIS satellite sensor are also generally well reproduced. Model calculations show that enhancements in inorganic aerosol concentrations simultaneously observed at the two sites 4 to 5 times during the one-month observation period were resulted by accumulation of pollutants under stagnated air condition. Because Beijing is located at the north border the high anthropogenic emission area (the Great North China Plain), northward motion of air under the influence of anti-cyclone system caused enhancements in fine aerosol concentrations at Beijing. Concentrations of primary aerosols, such as EC, are found to be generally controlled by emissions within 100 km around Beijing within previous 24 hours. On the other hand, emissions as far as 500 km within previous 3 days were found to affect concentrations of secondary aerosols, such as sulfate. Because of significant contributions of secondary aerosols in Beijing, regional emission controls are found to be necessary for improvement of air quality in Beijing.

  4. Measurement of the tau lepton mass by the Beijing Spectrometer (BES) Collaboration

    SciTech Connect

    Soderstrom, E.; BES Collaboration

    1992-11-01

    The mass of the {tau} lepton has been measured at the Beijing Electron Positron Collider using the Beijing Spectrometer. A search near threshold for e{sup +}e{sup {minus}} {yields} {tau}{sup +}{tau}{sup {minus}} was performed. Candidate events were identified by requiring that one {tau} decay via {tau} {yields} e{nu}{bar {nu}}, and the other via {tau} {yields} {mu}{nu}{bar {nu}}. The mass value, obtained from a fit to the energy dependence of the {tau}{sup +}{tau}{sup {minus}} cross section, is m{sub {tau}} = 1776.9{sub -0.5}{sup +0.4} {plus_minus} 0.2 MeV.

  5. The System Dynamics Research on the Private Cars' Amount in Beijing

    NASA Astrophysics Data System (ADS)

    Fan, Jie; Yan, Guang-Le

    The thesis analyzes the development problem of private cars’ amount in Beijing from the perspective of system dynamics. With the flow chart illustrating the relationships of relevant elements, the SD model is established by VENSIM to simulate the growth trend of private autos’ amount in the future on the background of “Public Transportation First” policy based on the original data in Beijing. Then the article discusses the forecasting impacts of “Single-and-double license plate number limit” on the number of city vehicles and private cars under the assumption that this policy implemented for long after the 2008 Olympic Games. Finally, some recommendations are put forward for proper control over this problem.

  6. Characteristics of size-segregated carbonaceous aerosols in the Beijing-Tianjin-Hebei region.

    PubMed

    Guo, Yuhong

    2016-07-01

    Mass concentrations of organic carbon (OC) and elemental carbon (EC) in size-resolved aerosols were investigated at four sites (three cities and one country) in the Beijing-Tianjin-Hebei region from September 2009 to August 2011. The size distributions of OC and EC presented large evolutions among rural and urban sites, and among four seasons, with highest peaks of OC and EC in fine mode in urban areas during winter. Geometric mean diameters (GMDs) of OC and EC in fine particles at urban sites during winter were lower than those at rural site mainly due to effects of fine particle coagulation and organic compound repartitioning. Fossil fuel emissions were a dominant source of OC and EC in urban areas, while biomass burning was a major source of OC and EC at rural site. Trajectory clustering and CWT analysis showed that regional transport was an important contributor to OC and EC in Beijing. PMID:27040539

  7. Characterization of land subsidence induced by groundwater withdrawals in Wenyu River alluvial fan, Beijing, China

    NASA Astrophysics Data System (ADS)

    Wang, R.; Luo, Y.; Yang, Y.; Tian, F.; Zhou, Y.; Tian, M.-Z.

    2015-11-01

    The Beijing plain area has suffered from severe land subsidence owing to groundwater overdraft. A major example is the Wenyu River alluvial fan in the Beijing plain area. This area has experienced as much as 10 m of land subsidence through 2000s. An integrated subsidence-monitoring program, including borehole extensometer and multilayer monitoring of groundwater, has been designed to meet the needs of monitoring land subsidence in this region. This work has allowed us to characterize land subsidence and understand the mechanical properties of the strata. The analysis results show the development of the land subsidence in this area is consistent with water-level change. The major strata contributing to compression deformation are Mid-Pleistocene stratum which contributed around 70 % of total subsidence. The shallow stratum and deep stratum show elastic mechanical behavior the intermediate stratum exhibit elastic-plastic mechanical behavior.

  8. Emerging markets for imported beef in China: Results from a consumer choice experiment in Beijing.

    PubMed

    Ortega, David L; Hong, Soo Jeong; Wang, H Holly; Wu, Laping

    2016-11-01

    The purpose of this study is to explore emerging markets for imported beef in China by assessing Beijing consumer demand for quality attributes. This study utilizes data from an in-store choice experiment to evaluate consumer willingness-to-pay for select food quality attributes (food safety, animal welfare, Green Food and Organic certification) taking into account country-of-origin information. Our results show that Beijing consumers value food safety information the most, and are willing to pay more for Australian beef products than for US or domestic (Chinese) beef. We explore the various relationships between the quality attributes, find evidence of preference heterogeneity and discuss agribusiness and marketing implications of our findings. PMID:27395825

  9. Impact of urban sprawl on carbon uptake in Beijing metropolitan area

    NASA Astrophysics Data System (ADS)

    Zhang, Jie; Pan, Xiaoling; Gao, Zhiqiang; Shi, Qingdong; Lv, Guanghui; Gao, Wei

    2005-09-01

    Increasing populations and economics intensify the urban growth and cropland encroachment in Beijing metropolitan area. In this paper we investigated the effects of recent urban sprawl (1991-2001) in Beijing metropolitan region, People's Republic of China on ecosystem net primary production (NPP). The analysis employed a mechanistic model of NPP in combination with satellite-derived and ecological data. Our analysis shows that urban growth in the 10-year study period significantly altered the urban ecosystem component of the regional carbon cycle. The annual amount of atmospheric carbon assimilated into phytomass through NPP was reduced by approximately 50.71×104 Mg C (-15.08%). More than half of this reduction is attributed to the loss of cultivated land. Vegetation removal and road disturbance by the expansion of urban areas reduced the amount of carbon uptake.

  10. Agricultural and urban land use change analysis in Changping County, Beijing, using remote sensing and GIS

    NASA Astrophysics Data System (ADS)

    Guo, Meng; Huang, Xiaoxia; Li, Hongga; Li, Xia; Ming, An

    Urban growth is regarded as a necessary transitional stage for a sustainable economy, but uncontrolled or arbitrary urban growth rapidly consumes rural resources and causes environmental pollution, ecological deterioration. In this paper, we developed a remote sensing and GIS-based integrated approach to monitor and analyze agricultural and urban spatial land use and ecological landscape change characteristics. In the proposed approach, multi-temporal satellite images from 1995 to 2010 were selected and classified to obtain land cover and use spatial changes. And GIS was used to analyze variation tendency for land use and ecological landscape indices. Experiments were performed in the Changping County, north of Beijing to analyze rapid urbanization effects in the past two decades, especially during the Beijing 2008 Olympic Games. The results indicate that there has been a notable urban growth and a visible loss about 38.8% in cropland, meanwhile dominated landscape structures and patterns have greatly changed from agriculture to urban in the study area.

  11. The Beijing Olympics as a Field Experiment - The Aerosol Footprint of a Megacity

    NASA Astrophysics Data System (ADS)

    Cermak, J.; Knutti, R.

    2009-04-01

    During the 2008 Olympic Summer Games, emission reductions were enforced in and around Beijing to improve the notoriously poor air quality in the city. In this presentation we explore the effect of these measures on the regional aerosol load. To this end, we compare satellite-retrieved aerosol optical thickness of that period with previous years. In addition to absolute changes we explore the 2008 situation in its meteorological context. Using a neural network approach we predict summer 2008 aerosol based on meteorological conditions. Predicted values are contrasted with observations. A statistically significant reduction of aerosol load is found in Beijing that decreases in magnitude and significance with increasing region size. Locally, the aerosol load (log(AOT)) was about 10-15% below the levels expected for the prevailing meteorological situation. The small size of this effect highlights the importance of regional aerosol transport.

  12. Use of Ceres-Wheat Model for Wheat Yield Forecast in Beijing

    NASA Astrophysics Data System (ADS)

    Wang, Xian; Zhao, Chunjiang; Li, Cunjun; Liu, Liangyun; Huang, Wenjiang; Wang, Pengxin

    The CERES-Wheat model was applied to simulate yields from 2005 to 2007 at Xiaotangshan of northern Beijing. Experiment datum required by CERESWheat model were all collected and checked. In addition, 1974-2004 climate records were taken and calculated as predictive weather scenario used for yield forecasting. The model calibration adopted simulation results of 2005 and which of the other two years were used for validation. Model calibration was made through comparing the field-observed and model-simulated results at five stages: (i) dates of anthesis and maturity; (ii) values of LAI; (iii) biomass yields of anthesis and maturity; (iv) dry matter of leaf, stem, and grain; (v) final wheat yield. This study revealed that CERES-Wheat model can be used for the prediction of wheat growth and yield in Beijing.

  13. Etude par spectroscopie de Coulomb de points quantiques lateraux individuels et couples

    NASA Astrophysics Data System (ADS)

    Pioro-Ladriere, Michel

    Des points quantiques contenant un nombre discret et variable d'electrons sont formes dans un gaz bi-dimensionnel d'electrons a l'aide de grilles metalliques. Le transport electrique, le blocage de spin et la detection de charge sont employes comme outils spectroscopiques permettant de sonder les proprietes de ces nanostructures. Ces techniques permettent aussi de controler exactement le nombres d'electrons confines dans des points quantiques individuels et couples en utilisant un patron de grille judicieux. Une technique de refroidissement en tension est developpee afin de minimiser les effets parasites du bruit telegraphique. Ce type de bruit de charge deteriore la stabilite des nanostructures laterales par l'activation d'un minuscule courant de fuite entre les grilles et le gaz bi-dimensionnel. Un modele expliquant le role du refroidissement en tension sur le courant de fuite est presente. L'activation du courant de fuite est confirmee par detection de charge. Les effets des interactions entre les electrons pieges dans un point quantique sont ensuite etudies dans un regime ou il est possible de comparer les resulats experimentaux avec ceux obtenus par diagonalisation exacte. L'etude demontre que la phase associee au facteur de remplissage nu = 2 est instable au-dessus d'un nombre critique d'electrons. Cette instabilite est confirmee experimentalement par blocage de spin. On demontre aussi l'existence d'etats correles dans le regime des renversements de spin, associe au passage de la phase nu = 2 a nu = 1. Les etats correles sont identifies par spectroscopie en transport non lineaire. Cette caracterisation du diagramme de phase de points individuels permet de coupler deux points quantiques configures a nu = 2. Pour ce regime, la nanostructure se comporte comme un systeme a deux niveaux pouvant contenir entre un et quatre electrons de valence et ce, meme si le nombre total d'electrons est plus eleve. Les degres de liberte de charge et de spin des deux points

  14. La structure de l'eau liquide: Une etude thermique par spectroscopie infrarouge

    NASA Astrophysics Data System (ADS)

    Larouche, Pascal

    Le probleme de la structure de l'eau liquide est important car l'eau est le liquide le plus present sur Terre, et complexe, la quete d'un modele precis pour decrire comment fonctionne ce liquide ayant debute des la fin du dix-neuvieme siecle. Cette etude aborde ce probleme en etudiant l'effet de l'augmentation de la temperature sur H2O et D 2O purs a l'aide de la spectroscopie infrarouge. L'intervalle de temperatures scrute est 29--93.1°C. Les spectres enregistres sont des spectres MIR-ATR entre 650 et 6000 cm-1 . L'analyse par facteurs de ces donnees permet de montrer que deux et seulement deux facteurs principaux sont necessaires pour decomposer tous les spectres experimentaux. Ces resultats sont confirmes grace a l'analyse par facteurs de spectres de la region FIR. Par la suite, la transformation en spectres de la partie reelle n et imaginaire k de l'indice de refraction permet de combiner les donnees des regions MIR et FIR. Une fois ce calcul termine, les spectres de transmission complets de H 2O et D2O entre 25 et 90°C sont connus. Ils sont ensuite utilises pour calculer par extrapolation le spectre des especes constituant l'eau liquide, puis leur abondance en fonction de la temperature. L'extrapolation de ces abondances montre que les especes correspondent a des temperatures limites de --18 et 122°C. Par la suite, la decomposition gaussienne des spectres d'especes met en evidence la riche structure de ces objets et permet de demontrer que l'apparent deplacement du massif d'absorption OH (OD) est produit par une variation de l'intensite des bandes et non pas de leur deplacement. L'examen attentif des spectres des especes prouve qu'il n'y a pas de OH libres crees par l'augmentation de la temperature: meme a 93.1°C, chaque molecule possede quatre liens-H. Ces conclusions sont de plus confirmees par une analyse thermodynamique du passage des molecules de la phase solide a la phase gazeuse. Pour diversifier la nature des resultats experimentaux utilises, des

  15. Prospects for the study of gluonic states at Beijing Electron- Positron Collider (BEPC)

    SciTech Connect

    Chanowitz, M.S.

    1989-01-11

    Progress in the study of gluonic states depends crucially on accumulating data samples of order 10/sup 8/ J//psi/ decays, in order to perform complete partial wave analyses of radiative and hadronic J//psi/ decays. This requirement is well matched to the capabilities of the Beijing Electron-Positron Collider, which has approached the necessary luminosity in its first two months of operation. 28 refs., 1 fig., 1 tab.

  16. Aerosol optical properties under the condition of heavy haze over an urban site of Beijing, China.

    PubMed

    Che, Huizheng; Xia, Xiangao; Zhu, Jun; Wang, Hong; Wang, Yaqiang; Sun, Junying; Zhang, Xiaoye; Shi, Guangyu

    2015-01-01

    In January 2013, several serious haze pollution events happened in North China. Cimel sunphotometer measurements at an urban site of Beijing (Chinese Academy of Meteorological Sciences-CAMS) from 1 to 30 January 2013 were used to investigate the detailed variation of aerosol optical properties. It was found that Angstrom exponents were mostly larger than 0.80 when aerosol optical depth values are higher than 0.60 at the urban region of Beijing during January 2013. The aerosol optical depth (AOD) at the urban region of Beijing can remain steady at approximately 0.40 before haze happening and then increased sharply to more than 1.50 at 500 nm with the onset of haze, which suggests that the fine-mode AOD is a factor of 20 of the coarse-mode AOD during a serious haze pollution event. The single scattering albedo was approximately 0.90 ± 0.03 at 440, 675, 870 and 1,020 nm during the haze pollution period. The single scattering albedo at 440 nm as a function of the fine-mode fraction was relatively consistent, but it was highly variable at 675, 870 and 1,020 nm. Except on January 12 and 18, all the fine-mode particle volumes were larger than those of coarse particles, which suggests that fine particles from anthropogenic activities made up most of the haze. Aerosol type classification analysis showed that the dominant aerosol types can be classified as both "mixed" and "urban/industrial (U/I) and biomass burning (BB)" categories during the heavy haze period of Beijing in January of 2013. The mixed category occurrence was about 31 %, while the U/I and BB was about 69 %. PMID:25106521

  17. Characteristics of re-suspended road dust and its impact on the atmospheric environment in Beijing

    NASA Astrophysics Data System (ADS)

    Han, Lihui; Zhuang, Guoshun; Cheng, Shuiyuan; Wang, Ying; Li, Juan

    A sampling campaign of re-suspended road dust samples from 53 sites that could cover basically the entire Beijing, soil samples from the source regions of dust storm in August 2003, and aerosol samples from three representative sites in Beijing from December 2001 to September 2003, was carried out to investigate the characteristics of re-suspended road dust and its impact on the atmospheric environment. Ca, S, Cu, Zn, Ni, Pb, and Cd were far higher than its crustal abundances and Ca 2+, SO 42-, Cl -, K +, Na +, NO 3- were major ions in re-suspended road dust. Al, Ti, Sc, Co, and Mg in re-suspended road dust were mainly originated from crustal source, while Cu, Zn, Ni, and Pb were mainly derived from traffic emissions and coal burning, and Fe, Mn, and Cd were mainly from industrial emissions, coal combustion and oil burning. Ca 2+ and SO 42- mainly came from construction activities, construction materials and secondary gas-particle conversions, Cl - and Na + were derived from industrial wastewater disposal and chemical industrial emissions, and NO 3- and K + were from vehicle emissions, photochemical reactions of NO X, biomass and vegetable burning. The contribution of mineral aerosol from inside Beijing to the total mineral aerosols was ˜30% in spring of 2002, ˜70% in summer of 2002, ˜80% in autumn of 2003, ˜20% in PM 10 and ˜50% in PM 2.5, in winter of 2002. The pollution levels of the major pollution species, Ca, S, Cu, Zn, Ni, Pb, Fe, Mn, and Cd in re-suspended road dust reached ˜76%, ˜87%, ˜75%, ˜80%, ˜82%, ˜90%, ˜45%, ˜51%, and ˜94%, respectively. Re-suspended road dust from the traffic and construction activities was one of the major sources of pollution aerosols in Beijing.

  18. Regional source identification of atmospheric aerosols in Beijing based on sulfur isotopic compositions

    NASA Astrophysics Data System (ADS)

    Lianfang, Wei; Pingqing, Fu; Xiaokun, Han; Qingjun, Guo; Yele, Sun; Zifa, Wang

    2016-04-01

    65 daily PM2.5 (aerosol particle with aerodynamic diameter less than 2.5 μm) samples were collected from an urban site in Beijing in four months representing the four seasons between September 2013 and July 2014. Inorganic ions, organic/elemental carbon and stable sulfur isotopes of sulfate aerosols were analyzed systematically. The "fingerprint" characteristics of the stable sulfur isotopic composition, together with trajectory clustering modeled by HYSPLIT-4 and potential source contribution function (PSCF), were employed for identifying potential regional sources. Results obviously exhibited the distinctive seasonality for various aerosol speciation associated with PM2.5 in Beijing with sulfate, nitrate, ammonium, organic matter, and element carbon being the dominant species. Elevated chloride associated with higher concentration of organics were found in autumn and winter, due to enhanced coal combustion emissions. The δ34S values of Beijing aerosol samples ranged from 2.94‰ to 10.2‰ with an average value of 6.18±1.87‰ indicating that the major sulfur source is direct fossil fuel burning-related emissions. Owning to a temperature-dependent fractionation and elevated biogenic sources of isotopically light sulfur in summer, the δ34S values had significant seasonal variations with a winter maximum ( 8.6‰)and a summer minimum ( 5.0‰). The results of trajectory clustering and the PSCF method demonstrated that higher concentrations of sulfate with lower sulfur isotope ratios ( 4.83‰) were associated with air masses from the south, southeast or east, whereas lower sulfate concentrations with higher δ34S values ( 6.69‰) when the air masses were mainly from north or northwest. These results suggested two main different kinds of regional coal combustion sources contributed to the pollution in Beijing.

  19. Beijing clades of Mycobacterium tuberculosis are associated with differential survival in HIV-negative Russian patients.

    PubMed

    Balabanova, Yanina; Nikolayevskyy, Vladyslav; Ignatyeva, Olga; Kontsevaya, Irina; Mironova, Svetlana; Kovalyov, Alexander; Kritsky, Andrey; Rodionova, Yulia; Fedorin, Ivan; Casali, Nicola; Hooper, Richard; Horstmann, Rolf D; Nejentsev, Sergey; Hoffner, Sven; Nuernberg, Peter; Drobniewski, Francis

    2015-12-01

    We conducted a prospective study to establish factors associated with survival in tuberculosis patients in Russia including social, clinical and pathogen-related genetic parameters. Specifically we wished to determine whether different strains/clades of the Beijing lineage exerted a differential effect of survival. HIV-negative culture-confirmed cases were recruited during 2008-2010 across Samara Oblast and censored in December 2011. Molecular characterization was performed by a combination of spoligotyping, multilocus VNTR typing and whole genome sequencing (WGS). We analyzed 2602 strains and detected a high prevalence of Beijing family (n=1933; 74%) represented largely by two highly homogenous dominant clades A (n=794) and B (n=402) and non-A/non-B (n=737). Multivariable analysis of 1366 patients with full clinical and genotyping data showed that multi- and extensive drug resistance (HR=1.86; 95%CI: 1.52, 2.28 and HR=2.19; 95%CI: 1.55, 3.11) had the largest impact on survival. In addition older age, extensive lung damage, shortness of breath, treatment in the past and alcohol abuse reduced survival time. After adjustment for clinical and demographic predictors there was evidence that clades A and B combined were associated with poorer survival than other Beijing strains (HR=0.48; 95%CI 0.34, 0.67). All other pathogen-related factors (polymorphisms in genes plcA, plcB, plcC, lipR, dosT and pks15/1) had no effect on survival. In conclusion, drug resistance exerted the greatest effect on survival of TB patients. Nevertheless we provide evidence for the independent biological effect on survival of different Beijing family strains even within the same defined geographical population. Better understanding of the role of different strain factors in active disease and their influence on outcome is essential. PMID:26319998

  20. Depth-dependent mechanisms that drive land subsidence in Beijing plain, China

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Gong, H.; Wang, R.; Liu, H.; Gu, Z.; Li, X.

    2014-12-01

    The Beijing city, located in the north of North China Plain, China, has undergone severe land subsidence for the last several decades. An integrated subsidence-monitoring program, including leveling survey, borehole extensometer and and Satellite radar interferometry (InSAR) time series analysis, has been designed to meet the needs of mapping and monitoring land subsidence in this region. The monitoring data reveal that the subsidence rates of plain area exhibit significant spatial variability, ranging from 1cm to 15cm/yr. The purpose of this article is to identify and analyze the natural and anthropogenic mechanisms that drive the land subsidence. The movement sources are described and classified by their depth of occurrence. We attribute effects of displacement of the Beijing plain to three major components: (1) shallow components, (2) mediate component, and (3) deep component. Deep components are recognized as tectonic movement of the pre-Tertiary basement. Medium component act at depths generally range of 50 to 450m, and include groundwater exploitation; geochemical compaction, due to the high salt concentration in the deep lacustrine sendiments. Shallow components are related to the settlement of building; natural consolidation, due to the compaction of the loose sediments occurred mainly in the clayey layers of the uppermost 26-m Holocene deposits and organic soil subsidence occurs mainly with drainage and development of peat by land reclamation. The latter factor primarily involve the southeast area of the Beijing plain. The loads of new buildings may also cause short-live compaction of shallow deposits. Groundwater exploitation is thought to be the major factor that contributes to the present land subsidence in the Beijing plain. Settlement caused by buildings loads cannot be omitted in newly developed area, but such phenomenon might be localized.

  1. Assessment of land degradation and its spatial and temporal variation in Beijing surrounding area

    NASA Astrophysics Data System (ADS)

    Li, Shuang; Dong, Suocheng; Zhang, Xiaojun; Zhiqiang, Gao

    2005-08-01

    The indulgence in willful persecution of sandstorm had made great attention of many countries around the world. Chinese government and the Chinese academy of science going with some other countries have devoted a large amount of vigor to study the crucial environment problem. Due to the main source areas of sandstorm all located in the arid and semi-arid regions where there have great area, hard natural condition and bad traffic condition, it's very difficult to accomplish source area and the reason of sandstorm. For this destination, a international cooperation organization has been established to clarify the occur mechanism, transfer process and the following environment impact of sandstorm. The organization includes many researchers come form USA, Japan, Korea, and so on. Beijing surrounding area is one of the main sandstorm sources in recent years. In order to understand fully of the sandstorm form and development, we analyzed the land use degradation of Beijing surrounding area during the last ten years. 71 scenes Landsat TM/ETM, 611 scenes DRG and DEM data had been processed in our study. This paper made a detail describe of using Landsat image data and high resolution DEM data to construe the soil erosion and vegetation degenerate. The result shows that the irrational human activities and land use style are the main factors of land use degradation. In case of Beijing surrounding area, the land degradation directly impacted the frequency and intensity of sand & dust storm in Northern China. The case study region of Beijing surrounding area includes 51 counties that belong to three provinces and autonomous regions.

  2. Effects of rigorous emission controls on reducing ambient volatile organic compounds in Beijing, China.

    PubMed

    Li, Jing; Wu, Rongrong; Li, Yaqi; Hao, Yufang; Xie, Shaodong; Zeng, Liming

    2016-07-01

    102 volatile organic compound (VOC) species were measured online using a gas chromatography-mass spectrometry/flame ionization detector (GC-MS/FID) at an urban site in Beijing in 11 August to 3 September 2015, when a series of rigorous air quality control measures were implemented in Beijing city and neighbouring provinces. Positive matrix factorization (PMF) was applied to identify emission sources from 1h averaged values of VOC data. Based on the online VOC data and the PMF analysis results, the effectiveness of different control measures were investigated. The PMF results were compared with an emission inventory data. Results show that the rigorous air quality restrictions implemented were successful. The averaged ambient VOC mixing ratios during the emission control period and non-control period were 27.53 and 45.42ppbv, respectively. The mixing ratios of total VOC during the control period were reduced by 40%. Alkanes were the most abundant chemical group in the two periods, followed by oxygenated volatile organic compounds (OVOCs). Almost all quantified VOC species decreased during the control period. Tracers of industrial sources and vehicle exhaust reduced most, including some halocarbons, esters and aromatics. Eight sources were resolved by online PMF analysis for ambient VOCs in Beijing. Contributions of those sources varied significantly during the control and non-control period. Compared with the values before control, contributions of vehicle-related sources were most reduced, followed by solvent utilization. Reductions of vehicle-related sources, solvent utilization, secondary formation, fuel combustion, and biogenic were responsible for 65%, 19%, 10%, 5%, and 1% of the reductions in ambient VOCs. Both PMF results and emission inventory data indicated that the control measure on traffic was very effective in reducing ambient VOCs in Beijing, with the emission reductions of about 50%. PMID:27039059

  3. Unusual Large-Scale Chromosomal Rearrangements in Mycobacterium tuberculosis Beijing B0/W148 Cluster Isolates

    PubMed Central

    Shitikov, Egor A.; Bespyatykh, Julia A.; Ischenko, Dmitry S.; Alexeev, Dmitry G.; Karpova, Irina Y.; Kostryukova, Elena S.; Isaeva, Yulia D.; Nosova, Elena Y.; Mokrousov, Igor V.; Vyazovaya, Anna A.; Narvskaya, Olga V.; Vishnevsky, Boris I.; Otten, Tatiana F.; Zhuravlev, Valery Y.; Yablonsky, Peter K.; Ilina, Elena N.; Govorun, Vadim M.

    2014-01-01

    The Mycobacterium tuberculosis (MTB) Beijing family isolates are geographically widespread, and there are examples of Beijing isolates that are hypervirulent and associated with drug resistance. One-fourth of Beijing genotype isolates found in Russia belong to the B0/W148 group. The aim of the present study was to investigate features of these endemic strains on a genomic level. Four Russian clinical isolates of this group were sequenced, and the data obtained was compared with published sequences of various MTB strain genomes, including genome of strain W-148 of the same B0/W148 group. The comparison of the W-148 and H37Rv genomes revealed two independent inversions of large segments of the chromosome. The same inversions were found in one of the studied strains after deep sequencing using both the fragment and mate-paired libraries. Additionally, inversions were confirmed by RFLP hybridization analysis. The discovered rearrangements were verified by PCR in all four newly sequenced strains in the study and in four additional strains of the same Beijing B0/W148 group. The other 32 MTB strains from different phylogenetic lineages were tested and revealed no inversions. We suggest that the initial largest inversion changed the orientation of the three megabase (Mb) segment of the chromosome, and the second one occurred in the previously inverted region and partly restored the orientation of the 2.1 Mb inner segment of the region. This is another remarkable example of genomic rearrangements in the MTB in addition to the recently published of large-scale duplications. The described cases suggest that large-scale genomic rearrangements in the currently circulating MTB isolates may occur more frequently than previously considered, and we hope that further studies will help to determine the exact mechanism of such events. PMID:24416324

  4. Spatial and temporal characteristics of air quality and air pollutants in 2013 in Beijing.

    PubMed

    Yan, Shujun; Cao, Hui; Chen, Ying; Wu, Chengzhen; Hong, Tao; Fan, Hailan

    2016-07-01

    Air pollution has become an ever more critical issue in Beijing in more recent years. In this study, we use the air quality index (AQI), corresponding primary pollutant types and meteorological data which are collected at 16 monitoring stations in Beijing between January 2013 and December, 2013 studying the spatial and temporal variations of air quality and air pollutants. The results show that PM2.5 was the most serious pollutant, followed by O3. The average PM2.5 mass concentration was 119.5 ± 13.8 μg m(-3) in Beijing. In addition, the air quality varies across different seasons. More specifically, winter season showed the worst air quality. Moreover, while particulate matter (PM2.5 and PM10) concentrations were relatively higher in the spring and winter seasons, gaseous pollutants (O3 and NO2) were more serious in the summer and autumn. In terms of spatial heterogeneity, the findings showed that AQI and PM2.5 concentrations were higher in south and lower in the north of the city, and the O3 showed exactly a pattern with the opposite direction-higher in the north and lower in the south. NO2 was found to have a greater impact on the central region compared with that in other regions. Furthermore, PM2.5 was found to be positively correlated with the relative humidity, but negatively correlated with wind speed and atmospheric pressure (P < 0.01). However, the dominant meteorological factors that influence the PM2.5 concentrations varied in different seasons. The results in this paper provide additional information for the effective control of the air pollution in Beijing. PMID:27040547

  5. HIV incidence among men who have sex with men in Beijing: a prospective cohort study

    PubMed Central

    Li, Dongliang; Li, Shuming; Liu, Yingjie; Gao, Yanjie; Yu, Mingrun; Yang, Xueying; Li, Qingchun; Jiang, Shulin; Zhou, Zhenhai; Zhang, Zheng; Yan, Li; Jiang, Guiyan; Xiao, Dong; Pan, Stephen W; Luo, Fengji; Ruan, Yuhua; Shao, Yiming

    2012-01-01

    Objectives (1) To assess the HIV incidence rate among men who have sex with men (MSM) in a large cohort study in Beijing, China and (2) to identify sociodemographic and behavioural risk factors of HIV seroconversion among MSM in Beijing, China. Design A prospective cohort study. Setting Baseline and follow-up visits were conducted among MSM in Beijing, China. Participants A cohort of 797 HIV-seronegative MSM was recruited from August to December 2009, with follow-up occurring after 6 and 12 months. Primary and secondary outcome measures At baseline and follow-up visits, participants reported sociodemographic and sexual behaviour information, and were tested for HIV, herpes simplex virus-2 (HSV-2) and syphilis with whole blood specimens. Cox regression analysis was used to identify factors associated with HIV seroconversion. Results Most study participants (86.8%) were retained by the 12-month follow-up. The HIV, HSV-2 and syphilis incidence rates were 8.09 (95% CI 6.92 to 9.26), 5.92 (95% CI 5.44 to 6.40) and 8.06 (95% CI 7.56 to 8.56) cases per 100 person-years, respectively. HIV seroconversion was significantly associated with being <25 years old, having <12 years of education, having >1 male sex partner in the past 6 months, and being syphilis positive or HSV-2 positive. Conclusions The HIV incidence among MSM in Beijing is serious. Interventions and treatment of sexually transmitted diseases (STD) should be combined with HIV control and prevention measures among MSM. PMID:23166133

  6. Formation mechanism of continuous extreme haze episodes in the megacity Beijing, China, in January 2013

    NASA Astrophysics Data System (ADS)

    Yang, Yiru; Liu, Xingang; Qu, Yu; Wang, Jingli; An, Junling; Zhang, Yuanhangi; Zhang, Fang

    2015-03-01

    The primary objective of this study is to investigate the formation and evolution mechanism of the regional haze in Beijing by analyzing the process of a severe haze episode that occurredfrom1 to 31 January 2013. The mass concentration of PM2.5 and its chemical components were simultaneously measured at the Beijing urban atmospheric environmental monitoring station. The haze was characterized by a high frequency, a long duration, a large influential region and an extremely high PM2.5 values (> 500 μg/m3). The primary factors driving the haze formation were stationary atmospheric flows (in both vertical and horizontal directions), while a temperature inversion, a lower planetary boundary layer and a higher RH accelerated the formation of the regional haze. In one incident, the temperature inversion layer occurred at a height of 130 m above ground level, which prevented the air pollutants from being dispersed vertically. The regional transport of pollutants also played an important role in the formation of the haze. Wind from the south of Beijing increased from 58% in January 2012 to 63% in January 2013. Because the area to the south of Beijing is characterized by high industrial development, the unusual wind direction favored the regional transport of pollutants and severely exacerbated the haze. SO42-, NO3- and NH4+ are the three major water-soluble ions that contributed to the formation of the haze. The high variability in Cl- and K+ indicated that large quantities of coal combustion and biomass burning occurred during the haze.

  7. Urban stress-induced biogenic VOC emissions and SOA-forming potentials in Beijing

    NASA Astrophysics Data System (ADS)

    Ghirardo, Andrea; Xie, Junfei; Zheng, Xunhua; Wang, Yuesi; Grote, Rüdiger; Block, Katja; Wildt, Jürgen; Mentel, Thomas; Kiendler-Scharr, Astrid; Hallquist, Mattias; Butterbach-Bahl, Klaus; Schnitzler, Jörg-Peter

    2016-03-01

    Trees can significantly impact the urban air chemistry by the uptake and emission of reactive biogenic volatile organic compounds (BVOCs), which are involved in ozone and particle formation. Here we present the emission potentials of "constitutive" (cBVOCs) and "stress-induced" BVOCs (sBVOCs) from the dominant broadleaf woody plant species in the megacity of Beijing. Based on the municipal tree census and cuvette BVOC measurements on leaf level, we built an inventory of BVOC emissions, and assessed the potential impact of BVOCs on secondary organic aerosol (SOA) formation in 2005 and 2010, i.e., before and after realizing the large tree-planting program for the 2008 Olympic Games. We found that sBVOCs, such as fatty acid derivatives, benzenoids, and sesquiterpenes, constituted a significant fraction ( ˜ 40 %) of the total annual BVOC emissions, and we estimated that the overall annual BVOC budget may have doubled from ˜ 4.8 × 109 g C year-1 in 2005 to ˜ 10.3 × 109 g C year-1 in 2010 due to the increase in urban greening, while at the same time the emission of anthropogenic VOCs (AVOCs) decreased by 24 %. Based on the BVOC emission assessment, we estimated the biological impact on SOA mass formation potential in Beijing. Constitutive and stress-induced BVOCs might produce similar amounts of secondary aerosol in Beijing. However, the main contributors of SOA-mass formations originated from anthropogenic sources (> 90 %). This study demonstrates the general importance to include sBVOCs when studying BVOC emissions. Although the main problems regarding air quality in Beijing still originate from anthropogenic activities, the present survey suggests that in urban plantation programs, the selection of low-emitting plant species has some potential beneficial effects on urban air quality.

  8. Quantitative evaluation of emission control of primary and secondary organic aerosol sources during Beijing 2008 Olympics

    NASA Astrophysics Data System (ADS)

    Guo, S.; Hu, M.; Guo, Q.; Zhang, X.; Schauer, J. J.; Zhang, R.

    2012-12-01

    To explore the primary and secondary sources of fine organic particles after the aggressive implementation of air pollution controls during 2008 Beijing Olympic Games, 12-h PM2.5 concentrations were measured at one urban and one upwind rural site during the CAREBeijing-2008 (Campaigns of Air quality REsearch in Beijing and surrounding region) summer field campaign. The PM2.5 concentrations were 72.5±43.6μg m3 and 64.3±36.2μg m-3 at the urban site and rural site, respectively, which were the lowest in recent years due to the implementation of drastic control measures and favorable weather conditions. Five primary and four secondary fine organic particle sources were quantified using a CMB (chemical mass balance) model and tracer-yield method. Compared with previous studies in Beijing, the contribution of vehicle emission increased, with diesel engines contributing 16.2±5.9% and 14.5±4.1% to the total organic carbon (OC) concentrations and gasoline vehicles accounting for 10.3±8.7% and 7.9±6.2% of the OC concentrations at two sites. Due to the implementation of emission control measures, the OC concentrations from important primary sources have been reduced, and secondary formation has become an important contributor to fine organic aerosols. Compared with the non-controlled period, primary vehicle contributions were reduced by 30% and 24% in the urban and regional area, and reductions in the contribution from coal combustion were 57% and 7%, respectively. These results demonstrate the emission control measures significantly alleviated the primary organic particle pollution in and around Beijing. However, the control effectiveness of secondary organic particles was not significant.

  9. Long-term measurements of trace gaseous pollutants over Beijing using Mini-MAX-DOAS instruments

    NASA Astrophysics Data System (ADS)

    Ma, Jianzhong; Jin, Junli; Shaiganfar, Reza; Wagner, Thomas

    2014-05-01

    Air quality in Beijing megacity has been of great concern in the atmospheric and environmental science community as well as public media. In addition to in situ measurements of ambient concentrations of air pollutants (e.g. NO2, SO2) near the ground, satellite data have also been used to analyze the long-term variation trend of urban pollution as well as the special emission control effect. However, the emission sources of pollutants in a megacity like Beijing are diverse and heterogeneously distributed in the urban canopy. Therefore, in situ surface measurement results may be quite different from one site to another depending on the representativeness of the chosen sites. Satellite measurements are found to have large biases in monitoring the air pollutant levels in a city due to both grid-smoothing and aerosol shielding effects. Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) is a passive remote sensing technology, which retrieves atmospheric trace gases by using scattered sun light from various elevation angles. Ground-based measurements by MAX-DOAS are especially sensitive to the tropospheric part of trace gas column, and can be used effectively to validate the satellite products for the troposphere. We have performed ground Mini-MAX-DOAS measurements at an urban site (39.95N, 116.32E) in Beijing since August 2008. The diurnal and seasonal variations of tropospheric NO2 vertical column densities were retrieved by analyzing the MAX-DOAS spectra obtained at this site. Such dataset were also used to validate the SCIMACHY and OMI satellite NO2 products for the period 2008-2009. Analyses of these MAX-DOAS spectra for SO2 and HCHO will be done in the near future to investigate the long-term variations of pollution level and character in Beijing over the past years.

  10. [Distribution Characteristics and Source Analysis of Dustfall Trace Elements During Winter in Beijing].

    PubMed

    Xiong, Qiu-lin; Zhao, Wen-ji; Guo, Xiao-yu; Chen, Fan-tao; Shu, Tong-tong; Zheng, Xiao-xia; Zhao, Wen-hui

    2015-08-01

    The dustfall content is one of the evaluation indexes of atmospheric pollution. Trace elements especially heavy metals in dustfall can lead to risks to ecological environment and human health. In order to study the distribution characteristics of trace elements, heavy metals pollution and their sources in winter atmospheric dust, 49 dustfall samples were collected in Beijing City and nearby during November 2013 to March 2014. Then the contents (mass percentages) of 40 trace elements were measured by Elan DRC It type inductively coupled plasma mass (ICP-MS). Test results showed that more than half of the trace elements in the dust were less than 10 mg x kg(-1); about a quarter were between 10-100 mg x kg-1); while 7 elements (Pb, Zr, Cr, Cu, Zn, Sr and Ba) were more than 100 mg x kg(-1). The contents of Pb, Cu, Zn, Bi, Cd and Mo of winter dustfall in Beijing city.were respectively 4.18, 4.66, 5.35, 6.31, 6.62, and 8.62 times as high as those of corresponding elements in the surface soil in the same period, which went beyond the soil background values by more than 300% . The contribution of human activities to dustfall trace heavy metals content in Beijing city was larger than that in the surrounding region. Then sources analysis of dustfall and its 20 main trace elements (Cd, Mo, Nb, Ga, Co, Y, Nd, Li, La, Ni, Rb, V, Ce, Pb, Zr, Cr, Cu, Zn, Sr, Ba) was conducted through a multi-method analysis, including Pearson correlation analysis, Kendall correlation coefficient analysis and principal component analysis. Research results indicated that sources of winter dustfall in Beijing city were mainly composed of the earth's crust sources (including road dust, construction dust and remote transmission of dust) and the burning of fossil fuels (vehicle emissions, coal combustion, biomass combustion and industrial processes). PMID:26591998

  11. Changing trends and serotype distribution of Shigella species in Beijing from 1994 to 2010

    PubMed Central

    2013-01-01

    Shigella species are a common cause of acute diarrheal disease in China. In this study, we characterized the changing trends and serotype distribution of Shigella species in Beijing from 1994 to 2010. A total of 5999 Shigella strains were isolated and serotyped from the 302nd Hospital in Beijing. The annual number of Shigella isolates reached a peak (n = 1192; 19.84%) in 1996 and then decreased annually, reaching the lowest point (n = 24; 0.41%) in 2010. S. flexneri 2a and S. sonnei were the most frequently isolated Shigella, with their respective isolates making up 53.3% and 27.6% of the total. Isolates of S. flexneri 4c, 4a, and x made up 3% respectively of the total isolates. Significant decreases in percentage of S. flexneri over time were observed. S. sonnei surpassed S. flexneri 2a as the predominant serotype in 2000. Most isolates were recovered from July to September; 13.6% of the isolates were recovered from children aged 0 to 5 years, and 16% were recovered from those aged 21 to 25 years. S. flexneri 2a and 5 were recovered mostly from males (33.41%, p < 0.001; and 0.46%, p < 0.001%; respectively), whereas S. flexneri 2b and 6, and S. sonnei were most often isolated from females. Continuous monitoring of Shigella showed that all 4 species and 27 serotypes were present in Beijing, China, during the study period. The emergence of S. sonnei and the overall decreasing isolation rate of Shigella in Beijing can potentially aid in the development of vaccine and control strategies for shigellosis in the city. PMID:23919811

  12. Effect of Ethanol/Water Solvents on Phenolic Profiles and Antioxidant Properties of Beijing Propolis Extracts.

    PubMed

    Sun, Chunli; Wu, Zhengshuang; Wang, Ziyan; Zhang, Hongcheng

    2015-01-01

    Propolis is a natural substance known to be beneficial for human health and used as a folk medicine in many parts of the world. In this study, phenolic profiles and antioxidant properties of Beijing propolis extracted by different ethanol/water solvents were analyzed. Our results reveal that phenolic compounds and antioxidant properties of propolis extracts were significantly dependent on the concentration of ethanol/water solvents. Totally, 29 phenolic compounds were identified: 12 phenolic acids, 13 flavonoids, and 4 phenolic acid esters. In particular, 75 wt.% ethanol/water solvent may be the best for the highest extraction yield and the strongest antioxidant properties. Caffeic acid, benzyl caffeate, phenethyl caffeate, 5-methoxy pinobanksin, pinobanksin, pinocembrin, pinobanksin-3-O-acetate, chrysin, and galangin were the characteristic compounds of Beijing propolis, and these compounds seem to verify that Beijing propolis may be poplar-type propolis. In addition, the presence of high level of pinobanksin-3-O-acetate in Chinese propolis may be a novel finding, representing one-third of all phenolics. PMID:26351514

  13. A Network Flow Analysis of the Nitrogen Metabolism in Beijing, China.

    PubMed

    Zhang, Yan; Lu, Hanjing; Fath, Brian D; Zheng, Hongmei; Sun, Xiaoxi; Li, Yanxian

    2016-08-16

    Rapid urbanization results in high nitrogen flows and subsequent environmental consequences. In this study, we identified the main metabolic components (nitrogen inputs, flows, and outputs) and used ecological network analysis to track the direct and integral (direct + indirect) metabolic flows of nitrogen in Beijing, China, from 1996 to 2012 and to quantify the structure of Beijing's nitrogen metabolic processes. We found that Beijing's input of new reactive nitrogen (Q, which represents nitrogen obtained from the atmosphere or nitrogen-containing materials used in production and consumption to support human activities) increased from 431 Gg in 1996 to 507 Gg in 2012. Flows to the industry, atmosphere, and household, and components of the system were clearly largest, with total integrated inputs plus outputs from these nodes accounting for 31, 29, and 15%, respectively, of the total integral flows for all paths. The flows through the sewage treatment and transportation components showed marked growth, with total integrated inputs plus outputs increasing to 3.7 and 5.2 times their 1996 values, respectively. Our results can help policymakers to locate the key nodes and pathways in an urban nitrogen metabolic system so they can monitor and manage these components of the system. PMID:27406465

  14. Ecological accounting and evaluation of urban economy: Taking Beijing city as the case

    NASA Astrophysics Data System (ADS)

    Ji, Xi

    2011-03-01

    Urban economy is confronted with increasing biophysical limitations derived from the exhaustion of natural resources and the depletion of environmental capacity, and human cultural diversity has been declining during the fast urbanization. The conventional anthropocentric economics, regarding the natural environment as the 'exterior' of human economy, is invalid in the scientific evaluation on the contribution of natural resources and environment as well as human culture when facing the current urban crises. The theory of embodied cosmic exergy, as the latest development of ecological economics and ecological thermodynamics, is introduced in this study to construct an ecological evaluation framework of urban economy. The advantage of embodied cosmic exergy dedicated to ecological economics has been discussed in comparison with other ecological evaluation alternatives. Transformities describing hierarchies and manifesting quality are systematically calculated and tabulated. A new framework of embodied cosmic exergy based on network accounting (EmexNA) is sketched out in this study, taking not only diversity flows but also ecological stocks into consideration. The stock based concept of 'ecological wealth' and the flow based concept of 'ecological cost' as well as related evaluation indicators are developed based on EmexNA. Taking Beijing city as the case, the network accounting and related ecological evaluation of a practical urban economy are carried out in this study in the light of the basic social, economic and environmental data available from 1990 to 2005 of Beijing. The system construction and the ecological mechanism of the development of Beijing economy are correspondingly illuminated and discussed.

  15. [Testing of Concentration and Characteristics of Particulate Matters Emitted from Stationary Combustion Sources in Beijing].

    PubMed

    Hu, Yue-qi; Wu, Xiao-dong; Wang, Chen; Liang, Yun-ping; Ma, Zhao-hui

    2016-05-15

    A self-built monitoring sampling system on particulate matters and water soluble ions emitted from stationary combustion sources and a size separated sampling system on particulate matters based on FPS4000 and ELPI + were applied to test particulate matters in fumes of typical stationary combustion sources in Beijing. The results showed that the maximum concentration of total particulate matters in fumes of stationary combustion sources in Beijing was 83.68 mg · m⁻³ in standard smoke oxygen content and the minimum was 0.12 mg · m⁻³. And particle number concentration was in the 10⁴-10⁶ cm⁻³ number of grade. Both mass and number concentration ranking order of particulate matters emitted from stationary combustion sources in Beijing was: heating gas fired boilers < power plant coal fired boilers < heating coal fired boilers. And two or three peaks existed under 1 µm of particulate size for both number size distribution and mass size distribution. The number concentration for PM₂.₅ accounted for over 99.8% of that for PM₁₀ and that for PM₀.₁ accounted for over 83% of that for PM₂.₅. But the proportions of PM₀.₁, and PM₂.₅ in PM₁₀ were significantly lower in quality analysis,the proportion of PM₂.₅ in PM₁₀ was about 82%, and that of PM₀.₁ in PM₂.₅ was about 27%-33%. PMID:27506016

  16. Ring of impact from the mega-urbanization of Beijing between 2000 and 2009

    NASA Astrophysics Data System (ADS)

    Jacobson, Mark Z.; Nghiem, Son V.; Sorichetta, Alessandro; Whitney, Natasha

    2015-06-01

    The transient climate, soil, and air quality impacts of the rapid urbanization of Beijing between 2000 and 2009 are investigated with three-dimensional computer model simulations. The simulations integrate a new satellite data set for urban extent and a geolocated crowd-sourced data set for road surface area and consider differences only in urban land cover and its physical properties. The simulations account for changes in meteorologically driven natural emissions but do not include changes in anthropogenic emissions resulting from urbanization and road network variations. The astounding urbanization, which quadrupled Beijing urban extent between 2000 and 2009 in terms of physical infrastructure change, created a ring of impact that decreased surface albedo, increased ground and near-surface air temperatures, increased vertical turbulent kinetic energy, and decreased the near-surface relative humidity and wind speed. The meteorological changes alone decreased near-surface particulate matter, nitrogen oxides (NOx), and many other chemicals due to vertical dilution but increased near-surface ozone due to the higher temperature and lower NO. Vertical dilution and wind stagnation increased elevated pollution layers and column aerosol extinction. In sum, the ring of impact around Beijing may have increased urban heating, dried soil, mixed pollutants vertically, aggravated air stagnation, and increased near-surface oxidant pollution even before accounting for changes in anthropogenic emissions.

  17. Anthropogenic and biogenic organic compounds in summertime fine aerosols (PM2.5) in Beijing, China

    NASA Astrophysics Data System (ADS)

    Yang, Fan; Kawamura, Kimitaka; Chen, Jing; Ho, Kinfai; Lee, Shuncheng; Gao, Yuan; Cui, Long; Wang, Tieguan; Fu, Pingqing

    2016-01-01

    Ambient fine aerosol samples (PM2.5) were collected at an urban site (PKU) in Beijing and its upwind suburban site (Yufa) during the CAREBEIJING-2007 field campaign. Organic molecular compositions of the PM2.5 samples were studied for seven organic compound classes (sugars, lignin/resin acids, hydroxy-/polyacids, aromatic acids, biogenic SOA tracers, fatty acids and phthalates) using capillary GC/MS to better understand the characteristics and sources of organic aerosol pollution in Beijing. More than 60 individual organic species were detected in PM2.5 and were grouped into different compound classes based on their functional groups. Concentrations of total quantified organics at Yufa (469-1410 ng m-3, average 1050 ng m-3) were slightly higher than those at PKU (523-1390 ng m-3, 900 ng m-3). At both sites, phthalates were found as the most abundant compound class. Using a tracer-based method, the contributions of the biogenic secondary organic carbon (SOC) to organic carbon (OC) were 3.1% at PKU and 5.5% at Yufa, among which isoprene-SOC was the dominant contributor. In addition, most of the measured organic compounds were higher at Yufa than those at PKU, indicating a more serious pollution in its upwind region than in urban Beijing.

  18. Intensification of aerosol pollution associated with its feedback with surface solar radiation and winds in Beijing

    NASA Astrophysics Data System (ADS)

    Yang, Xin; Zhao, Chuanfeng; Guo, Jianping; Wang, Yang

    2016-04-01

    Beijing has been experiencing serious air pollution in recent years, resulting in serious impacts on the local environment and climate and on human health. In addition to individual pollution sources and weather systems, feedback between aerosols and downwelling solar radiation (DSR) and between aerosols and winds also contribute to heavy aerosol pollution. By using atmospheric visibility (VIS) to represent the relative amount of aerosol pollution during a 5 week observation around the Asia-Pacific Economic Cooperation (APEC) period (22 October to 25 November 2014) over a site in south Beijing, China, we show clear positive relationships between DSR and VIS and between winds and VIS. The sensitivities of daily DSR and surface winds to VIS are approximately 15.42 W/m2/km and 0.068 m/s/km, respectively. The strengthening contributions to atmospheric visibility by surface DSR-VIS interactions and between surface wind-aerosol interactions are estimated at approximately 15% and 12%, respectively, in south Beijing around the APEC period.

  19. [Research on monitoring land subsidence in Beijing plain area using PS-InSAR technology].

    PubMed

    Gu, Zhao-Qin; Gong, Hui-Li; Zhang, You-Quan; Lu, Xue-Hui; Wang, Sa; Wang, Rong; Liu, Huan-Huan

    2014-07-01

    In the present paper, the authors use permanent scatterers synthetic aperture radar interferometry (PS-InSAR) technique and 29 acquisitions by Envisat during 2003 to 2009 to monitor and analyze the spatial-temporal distribution and mechanism characterize of land subsidence in Beijing plain area. The results show that subsidence bowls have been bounded together in Beijing plain area, which covers Chaoyang, Changping, Shunyi and Tongzhou area, and the range of subsidence has an eastward trend. The most serious regional subsidence is mainly distributed by the quaternary depression in Beijing plain area. PS-Insar results also show a new subsidence bowl in Pinggu. What's more, the spatial and temporal distribution of deformation is controlled mainly by faults, such as Liangxiang-Shunyi fault, Huangzhuang-Gaoliying fault, and Nankou-Sunhe fault. The subsidence and level of groundwater in study area shows a good correlation, and the subsidence shows seasonal ups trend during November to March and seasonal downs trend during March to June along with changes in groundwater levels. The contribution of land subsidence is also influenced by stress-strain behavior of aquitards. The compaction of aquitards shows an elastic, plastic, viscoelastic pattern. PMID:25269304

  20. Spatial variation in the ecological relationships among the components of Beijing's carbon metabolic system.

    PubMed

    Xia, Linlin; Fath, Brian D; Scharler, Ursula M; Zhang, Yan

    2016-02-15

    In this paper, we construct a spatially explicit model of carbon metabolism for the flows of carbon among the components of an urban area. We used the model to identify spatial heterogeneity in the ecological relationships within a carbon metabolic network. We combined land-use and cover type maps for Beijing from 1990 to 2010 with empirical coefficients and socioeconomic data to quantify the flows. We used utility analysis to determine the ecological relationships between the components of the system and analyzed their changes during urban development. We used ArcGIS to analyze their spatial variation. We found that the positive utilities in Beijing decreased over time and that negative relationships mostly outweighed positive relationships after 2000. The main ecological relationships were distributed throughout the entire urban area before 2000; subsequently, exploitation, control, and mutualism relationships became concentrated in the southeast, leaving competition relationships to dominate the northwest. Mutualism relationships were most common for natural components, but were not stable because they were easily disturbed by urban expansion. Transportation and industrial land and urban land were the most important contributors to exploitation and control relationships and may be important indicators of spatial adjustment. Increasing competition relationships unbalanced the carbon metabolism, and limitations on the area of land available for development and on the water resources led to increasingly serious competition. The results provide an objective basis for planning adjustments to Beijing's land-use patterns to improve its carbon metabolism and reduce carbon emission. PMID:26657253

  1. Using stable isotopes to trace sources and formation processes of sulfate aerosols from Beijing, China

    PubMed Central

    Han, Xiaokun; Guo, Qingjun; Liu, Congqiang; Fu, Pingqing; Strauss, Harald; Yang, Junxing; Hu, Jian; Wei, Lianfang; Ren, Hong; Peters, Marc; Wei, Rongfei; Tian, Liyan

    2016-01-01

    Particulate pollution from anthropogenic and natural sources is a severe problem in China. Sulfur and oxygen isotopes of aerosol sulfate (δ34Ssulfate and δ18Osulfate) and water-soluble ions in aerosols collected from 2012 to 2014 in Beijing are being utilized to identify their sources and assess seasonal trends. The mean δ34S value of aerosol sulfate is similar to that of coal from North China, indicating that coal combustion is a significant contributor to atmospheric sulfate. The δ34Ssulfate and δ18Osulfate values are positively correlated and display an obvious seasonality (high in winter and low in summer). Although an influence of meteorological conditions to this seasonality in isotopic composition cannot be ruled out, the isotopic evidence suggests that the observed seasonality reflects temporal variations in the two main contributions to Beijing aerosol sulfate, notably biogenic sulfur emissions in the summer and the increasing coal consumption in winter. Our results clearly reveal that a reduction in the use of fossil fuels and the application of desulfurization technology will be important for effectively reducing sulfur emissions to the Beijing atmosphere. PMID:27435991

  2. Ambient air quality trends and driving factor analysis in Beijing, 1983-2007.

    PubMed

    Zhang, Ju; Ouyang, Zhiyun; Miao, Hong; Wang, Xiaoke

    2011-01-01

    The rapid development in Beijing, the capital of China, has resulted in serious air pollution problems. Meanwhile great efforts have been made to improve the air quality, especially since 1998. The variation in air quality under the interaction of pollution and control in this mega city has attracted much attention. We analyzed the changes in ambient air quality in Beijing since the 1980's using the Daniel trend test based on data from long-term monitoring stations. The results showed that different pollutants displayed three trends: a decreasing trend, an increasing trend and a flat trend. SO2, dustfall, B[a]P, NO2 and PM10 fit decreasing trend pattern, while NOx showed an increasing trend, and CO, ozone pollution, total suspended particulate (TSP), as well as Pb fit the flat trend. The cause of the general air pollution in Beijing has changed from being predominantly related to coal burning to mixed traffic exhaust and coal burning related pollution. Seasonally, the pollution level is typically higher during the heating season from November to the following March. The interaction between pollution sources change and implementation of air pollution control measures was the main driving factor that caused the variation in air quality. Changes of industrial structure and improved energy efficiency, the use of clean energy and preferred use of clean coal, reduction in pollution sources, and implementation of advanced environmental standards have all contributed to the reduction in air pollution, particularly since 1998. PMID:22432333

  3. Revolutionary narratives of self-compassion among older women in post-Mao Beijing.

    PubMed

    Shea, Jeanne L

    2014-01-01

    Drawing upon interviews and participant observation conducted with hundreds of middle-aged and elderly Chinese women in rural and urban neighborhoods in Beijing Municipality between 1993 and 2012, this paper explores the emergence of revolutionary new narratives of self-compassion among older women in reform-era Beijing. Taught before 1949 that they should first and foremost serve their families and after 1949 that they should put their own individual needs aside and serve the party and the masses, many older Chinese women in Beijing - after the seeds of market reform were sown in the late 1970s - slowly began to focus more attention than before on themselves, their past and present experiences, sources of and solutions to past and present distress, and their own personal enjoyment of everyday life. The analysis shows how western theories of both gero-transcendence and individualization as modernization are insufficient to account for the complex cultural formations of self-care that have developed among older women in the first decades of post-Mao China. PMID:24506769

  4. Modeling study on the factors affecting regional air quality during the Beijing 2008 Olympic Games

    NASA Astrophysics Data System (ADS)

    Wei, C.; Carmichael, G. R.; Adhikary, B.; D'Allura, A.; Cheng, Y.; Tang, Y.; Zhang, Q.; Streets, D. G.; Pierce, R.; Al-Saadi, J. A.; Flowers, B. A.; Dubey, M. K.; Krotkov, N. A.; Pickering, K. E.; Ramanathan, V.

    2009-12-01

    Chinese government took measures to control emissions of pollutants before and during the Beijing 2008 Olympic Games in order to get better air quality for the event. A 3-dimensional regional chemical transport model, the University of Iowa’s Sulfur Transport and dEposition Model (STEM), is used to evaluate the effects of emission reductions on regional air quality by this event. The emission inventories with and without the consideration of emission reductions are used in case studies. Impacts of the emissions from different regions and sectors on Beijing and regional air quality are discussed in this study. Meteorological factor on the improvement of air quality during this event is also assessed by using the meteorological conditions from different years to drive the model. Model performance is evaluated by comparing the modeled trace gases and aerosols with the surface measurements from Beijing, the field observations from the Cheju ABC Plume-Asian Monsoon Experiment (CAPMEX) during this summer, and satellite data from NASA.

  5. Input-Output Modeling for Urban Energy Consumption in Beijing: Dynamics and Comparison

    PubMed Central

    Zhang, Lixiao; Hu, Qiuhong; Zhang, Fan

    2014-01-01

    Input-output analysis has been proven to be a powerful instrument for estimating embodied (direct plus indirect) energy usage through economic sectors. Using 9 economic input-output tables of years 1987, 1990, 1992, 1995, 1997, 2000, 2002, 2005, and 2007, this paper analyzes energy flows for the entire city of Beijing and its 30 economic sectors, respectively. Results show that the embodied energy consumption of Beijing increased from 38.85 million tonnes of coal equivalent (Mtce) to 206.2 Mtce over the past twenty years of rapid urbanization; the share of indirect energy consumption in total energy consumption increased from 48% to 76%, suggesting the transition of Beijing from a production-based and manufacturing-dominated economy to a consumption-based and service-dominated economy. Real estate development has shown to be a major driving factor of the growth in indirect energy consumption. The boom and bust of construction activities have been strongly correlated with the increase and decrease of system-side indirect energy consumption. Traditional heavy industries remain the most energy-intensive sectors in the economy. However, the transportation and service sectors have contributed most to the rapid increase in overall energy consumption. The analyses in this paper demonstrate that a system-wide approach such as that based on input-output model can be a useful tool for robust energy policy making. PMID:24595199

  6. Heavy metal concentrations in roadside soils and correlation with urban traffic in Beijing, China.

    PubMed

    Chen, Xi; Xia, Xinghui; Zhao, Ye; Zhang, Ping

    2010-09-15

    A detailed investigation was conducted to study the heavy metal concentrations in roadside soils of Beijing. The concentrations of Cd, Cu, Pb and Zn showed a decreasing trend with increasing distance from the road while such trend was not identified in As, Cr and Ni. In addition, the concentrations of Cd, Cu, Pb and Zn significantly positively correlated with black carbon (BC) and TOC (p<0.01). The soil samples from West 2nd Ring Road with the highest traffic volume had the highest heavy metal concentrations of the 10 roads, and Pb concentration was significantly positively correlated with traffic volumes (p<0.05). According to the soil guideline values of China, Cd was considered to have considerable contamination in roadside soils, while Cu, Pb and Zn less, but As, Ni, Cr none. The concentrations of heavy metals in roadside soils of Beijing were considered medium or low in comparison with those in other cities; this may be due to the windy and dry climate in Beijing. The heavy metals could move with wind along the wind direction and the soil samples had higher heavy metal concentrations at the downwind direction. PMID:20541319

  7. Consumption and Sources of Dietary Salt in Family Members in Beijing

    PubMed Central

    Zhao, Fang; Zhang, Puhong; Zhang, Lu; Niu, Wenyi; Gao, Jianmei; Lu, Lixin; liu, Caixia; Gao, Xian

    2015-01-01

    In China, few people are aware of the amount and source of their salt intake. We conducted a survey to investigate the consumption and sources of dietary salt using the “one-week salt estimation method” by weighing cooking salt and major salt-containing food, and estimating salt intake during dining out based on established evidence. Nine hundred and three families (1981 adults and 971 children) with students in eight primary or junior high schools in urban and suburban Beijing were recruited. On average, the daily dietary salt intake of family members in Beijing was 11.0 (standard deviation: 6.2) g for children and adolescents (under 18 years old), 15.2 (9.1) g for adults (18 to 59 years old), and 10.2 (4.8) g for senior citizens (60 years old and over), respectively. Overall, 60.5% of dietary salt was consumed at home, and 39.5% consumed outside the home. Approximately 90% of the salt intake came from cooking (household cooking and cafeteria or restaurant cooking), while less than 10% came from processed food. In conclusion, the dietary salt intake in Beijing families far surpassed the recommended amounts by World Health Organization, with both household cooking and dining-out as main sources of salt consumption. More targeted interventions, especially education about major sources of salt and corresponding methods for salt reduction should be taken to reduce the risks associated with a high salt diet. PMID:25867952

  8. Risk of human exposure to polycyclic aromatic hydrocarbons: A case study in Beijing, China.

    PubMed

    Yu, Yanxin; Li, Qi; Wang, Hui; Wang, Bin; Wang, Xilong; Ren, Aiguo; Tao, Shu

    2015-10-01

    Polycyclic aromatic hydrocarbons (PAHs) can cause adverse effects on human health. The relative contributions of their two major intake routes (diet and inhalation) to population PAH exposure are still unclear. We modeled the contributions of diet and inhalation to the overall PAH exposure of the population of Beijing in China, and assessed their human incremental lifetime cancer risks (ILCR) using a Mont Carlo simulation approach. The results showed that diet accounted for about 85% of low-molecular-weight PAH (L-PAH) exposure, while inhalation accounted for approximately 57% of high-molecular-weight PAH (H-PAH) exposure of the Beijing population. Meat and cereals were the main contributors to dietary PAH exposure. Both gaseous- and particulate-phase PAHs contributed to L-PAH exposure through inhalation, whereas exposure to H-PAHs was mostly from the particulate-phase. To reduce the cancer incidence of the Beijing population, more attention should be given to inhaled particulate-phase PAHs with considerable carcinogenic potential. PMID:26017113

  9. Coupled Monitoring and Modeling of Air Quality and Regional Climate during the 2008 Beijing Olympic Games

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Smith, J. A.; Michel, A. P.; Baeck, M. L.; Wang, Z.; Fast, J. D.; Gmachl, C.

    2009-12-01

    The 2008 Summer Olympic Games focused attention on the air quality of Beijing, China, especially through emission reduction measures designed to improve air quality for the 2008 Games. The Quantum Cascade Laser Open-Path System (QCLOPS) is a mid-infrared laser absorption spectrometer that uses a tunable, thermoelectrically cooled, and pulsed quantum cascade laser for continuous measurement of multiple trace gases. QCLOPS was used in a field campaign from July to September 2008 in Beijing to study trace gas concentrations before, during, and after the Olympic Games to examine changes induced by emissions reduction methods. Jointly, numerical simulation experiments were carried out with the Weather Research and Forecasting Model with chemistry module (WRF-Chem) for the same time period to examine the air quality, regional climate, and aerosol-cloud-precipitation interactions in the Beijing metropolitan region, by taking advantage of high-resolution emission inventories developed by the Institute of Atmospheric Physics - Chinese Academy of Sciences to represent the effects of emission reduction policies for the Olympic period. Intercomparisons between QCLOPS observations and WRF-Chem simulations were performed, and results are presented. Furthermore we present detailed analyses on the atmospheric environment and air quality variables during the first week of August in 2008 followed by the opening ceremony of the 2008 Summer Olympics.

  10. PM₂.₅ emissions from light-duty gasoline vehicles in Beijing, China.

    PubMed

    Shen, Xianbao; Yao, Zhiliang; Huo, Hong; He, Kebin; Zhang, Yingzhi; Liu, Huan; Ye, Yu

    2014-07-15

    As stricter standards for diesel vehicles are implemented in China, and the use of diesel trucks is forbidden in urban areas, determining the contribution of light-duty gasoline vehicles (LDGVs) to on-road PM2.5 emissions in cities is important. Additionally, in terms of particle number and size, particulates emitted from LDGVs have a greater health impact than particulates emitted from diesel vehicles. In this work, we measured PM2.5 emissions from 20 LDGVs in Beijing, using an improved combined on-board emission measurement system. We compared these measurements with those reported in previous studies, and estimated the contribution of LDGVs to on-road PM2.5 emissions in Beijing. The results show that the PM2.5 emission factors for LDGVs, complying with European Emission Standards Euro-0 through Euro-4 were: 117.4 ± 142, 24.1 ± 20.4, 4.85 ± 7.86, 0.99 ± 1.32, 0.17 ± 0.15 mg/km, respectively. Our results show a significant decline in emissions with improving vehicle technology. However, this trend is not reflected in recent emission inventory studies. The daytime contributions of LDGVs to PM2.5 emissions on highways, arterials, residential roads, and within urban areas of Beijing were 44%, 62%, 57%, and 57%, respectively. The contribution of LDGVs to PM2.5 emissions varied both for different road types and for different times. PMID:24810889

  11. Quantum cascade laser open-path system for remote sensing of trace gases in Beijing, China

    NASA Astrophysics Data System (ADS)

    Michel, Anna P. M.; Liu, Peter Q.; Yeung, June K.; Corrigan, Paul; Baeck, Mary Lynn; Wang, Zifa; Day, Timothy; Smith, James A.

    2010-11-01

    Exploiting several key characteristics of quantum cascade (QC) lasers, including wide tunability and room-temperature operation, the Quantum Cascade Laser Open-Path System (QCLOPS) was designed for the detection of a range of trace gases and for field deployment in urban environments. Tunability over a wavelength range from 9.3 to 9.8 μm potentially provides the capability for monitoring ozone, ammonia, and carbon dioxide, a suite of trace gases important for air quality and regional climate applications in urban environments. The 2008 Olympic Games in Beijing, China drew attention to air quality problems in urban environments. Prior to and during the Olympic games, regional air quality modifications through factory shutdowns, car restrictions, and construction halts in Beijing and its surrounding areas created a unique test bed for new sensor technologies such as the QCLOPS sensor. We report the design of this novel, open-path air quality sensor and the results of both laboratory tests and field trials during the 2008 Olympic Games in Beijing, China.

  12. Effect of Ethanol/Water Solvents on Phenolic Profiles and Antioxidant Properties of Beijing Propolis Extracts

    PubMed Central

    Sun, Chunli; Wu, Zhengshuang; Wang, Ziyan; Zhang, Hongcheng

    2015-01-01

    Propolis is a natural substance known to be beneficial for human health and used as a folk medicine in many parts of the world. In this study, phenolic profiles and antioxidant properties of Beijing propolis extracted by different ethanol/water solvents were analyzed. Our results reveal that phenolic compounds and antioxidant properties of propolis extracts were significantly dependent on the concentration of ethanol/water solvents. Totally, 29 phenolic compounds were identified: 12 phenolic acids, 13 flavonoids, and 4 phenolic acid esters. In particular, 75 wt.% ethanol/water solvent may be the best for the highest extraction yield and the strongest antioxidant properties. Caffeic acid, benzyl caffeate, phenethyl caffeate, 5-methoxy pinobanksin, pinobanksin, pinocembrin, pinobanksin-3-O-acetate, chrysin, and galangin were the characteristic compounds of Beijing propolis, and these compounds seem to verify that Beijing propolis may be poplar-type propolis. In addition, the presence of high level of pinobanksin-3-O-acetate in Chinese propolis may be a novel finding, representing one-third of all phenolics. PMID:26351514

  13. Hypertension Detection, Management, Control and Associated Factors Among Residents Accessing Community Health Services In Beijing

    PubMed Central

    JIANG, Bin; LIU, Hongmei; RU, Xiaojuan; ZHANG, Hui; WU, Shengping; WANG, Wenzhi

    2014-01-01

    The aim of this study was to analyse high blood pressure detection, management, control and associated factors among residents accessing community health services (CHSs) in Beijing. We screened for HBP in 9524 individuals aged 50 years or older who accessed care in four Beijing CHSs. Among the 9397 residents with questionnaire responses that qualified them for inclusion in the study, 5029 patients with HBP were identified, 1510 (i.e., 30% of the HBP patient group) of whom were newly identified cases. The rate of hypertension detection was 53.5%. Among the 5029 HBP patients, the rates of awareness, treatment and control of hypertension were 70.0%, 62.1% and 29.6%, respectively. In general, the rate of hypertension control was higher when the rates of hypertension awareness and treatment were higher in subgroups stratified by different sociodemographic and risk factors, except for the overweight and obesity subgroups. In conclusion, suboptimal HBP awareness, treatment, and control are still major problems confronting CHSs in Beijing. Control of hypertension in the population may be improved by increasing awareness and improving the treatment of hypertension in CHSs. PMID:24784167

  14. [Trends and variation of CFC-11 in the atmosphere of Beijing].

    PubMed

    Xiu, Tian-yang; Wang, Yue-si; Sun, Yang; Xu, Xin; Liu, Guang-Ren

    2005-01-01

    In recent years, concentration of CFC in the atmosphere has undergone rapid changes especially in association with human activities. For the influence of CFC on climate changes and environment changes, the concentration of atmospheric CFC-11 in Beijing is continuously observed and analyzed by a gas chromatography-mass spectrometry. The seasonal variation concentration and trends of CFC-11 are reported. The results show that the seasonal variation of CFC-11 was basically similar from 1999 to 2003. There was one peak value in the seasonal variation of CFC-11 in 1999-2003. The highest monthly average concentration of CFC-11 was 1149.5 +/- 531.9 x 10(12) ( V x V(-1)) in summer and the lowest monthly average concentration of CFC-11 was 487.5 +/- 131.5 x 10(-12) (V x V(-1)) in spring. The annual average concentration of CFC-11 was increasing in Beijing atmosphere from 1995 to 1998, and the average increasing ratio was 17.9%. The annual average concentration of CFC-11 was slowly decreasing from 1999, and the average decreasing ratio was 10.7%. The average concentration of CFC-11 in the atmosphere of Beijing was 3 to approximately 5 times of the average concentration of CFC-11 in the atmosphere of Mauna Loa Station of U.S.A. PMID:15859398

  15. Consumption and sources of dietary salt in family members in Beijing.

    PubMed

    Zhao, Fang; Zhang, Puhong; Zhang, Lu; Niu, Wenyi; Gao, Jianmei; Lu, Lixin; Liu, Caixia; Gao, Xian

    2015-04-01

    In China, few people are aware of the amount and source of their salt intake. We conducted a survey to investigate the consumption and sources of dietary salt using the "one-week salt estimation method" by weighing cooking salt and major salt-containing food, and estimating salt intake during dining out based on established evidence. Nine hundred and three families (1981 adults and 971 children) with students in eight primary or junior high schools in urban and suburban Beijing were recruited. On average, the daily dietary salt intake of family members in Beijing was 11.0 (standard deviation: 6.2) g for children and adolescents (under 18 years old), 15.2 (9.1) g for adults (18 to 59 years old), and 10.2 (4.8) g for senior citizens (60 years old and over), respectively. Overall, 60.5% of dietary salt was consumed at home, and 39.5% consumed outside the home. Approximately 90% of the salt intake came from cooking (household cooking and cafeteria or restaurant cooking), while less than 10% came from processed food. In conclusion, the dietary salt intake in Beijing families far surpassed the recommended amounts by World Health Organization, with both household cooking and dining-out as main sources of salt consumption. More targeted interventions, especially education about major sources of salt and corresponding methods for salt reduction should be taken to reduce the risks associated with a high salt diet. PMID:25867952

  16. Environmental impact assessment of solid waste management in Beijing City, China

    SciTech Connect

    Zhao Yan; Christensen, Thomas H.; Lu Wenjing; Wu Huayong; Wang Hongtao

    2011-04-15

    The environmental impacts of municipal solid waste management in Beijing City were evaluated using a life-cycle-based model, EASEWASTE, to take into account waste generation, collection, transportation, treatment/disposal technologies, and savings obtained by energy and material recovery. The current system, mainly involving the use of landfills, has manifested significant adverse environmental impacts caused by methane emissions from landfills and many other emissions from transfer stations. A short-term future scenario, where some of the landfills (which soon will reach their capacity because of rising amount of waste in Beijing City) are substituted by incinerators with energy recovery, would not result in significant environmental improvement. This is primarily because of the low calorific value of mixed waste, and it is likely that the incinerators would require significant amounts of auxiliary fuels to support combustion of wet waste. As for the long-term future scenario, efficient source separation of food waste could result in significant environmental improvements, primarily because of increase in calorific value of remaining waste incinerated with energy recovery. Sensitivity analysis emphasized the importance of efficient source separation of food waste, as well as the electricity recovery in incinerators, in order to obtain an environmentally friendly waste management system in Beijing City.

  17. Statistical corruption in Beijing's air quality data has likely ended in 2012

    NASA Astrophysics Data System (ADS)

    Stoerk, Thomas

    2016-02-01

    This research documents changes in likely misreporting in official air quality data from Beijing for the years 2008-2013. It is shown that, consistent with prior research, the official Chinese data report suspiciously few observations that exceed the politically important Blue Sky Day threshold, a particular air pollution level used to evaluate local officials, and an excess of observations just below that threshold. Similar data, measured by the US Embassy in Beijing, do not show this irregularity. To document likely misreporting, this analysis proposes a new way of comparing air quality data via Benford's Law, a statistical regularity known to fit air pollution data. Using this method to compare the official data to the US Embassy data for the first time, I find that the Chinese data fit Benford's Law poorly until a change in air quality measurements at the end of 2012. From 2013 onwards, the Chinese data fit Benford's Law closely. The US Embassy data, by contrast, exhibit no variation over time in the fit with Benford's Law, implying that the underlying pollution processes remain unchanged. These findings suggest that misreporting of air quality data for Beijing has likely ended in 2012. Additionally, I use aerosol optical density data to show the general applicability of this method of detecting likely misreporting in air pollution data.

  18. On the source contribution to Beijing PM2.5 concentrations

    NASA Astrophysics Data System (ADS)

    Zíková, Naděžda; Wang, Yungang; Yang, Fumo; Li, Xinghua; Tian, Mi; Hopke, Philip K.

    2016-06-01

    Beijing is a city with some of the world's worst particulate air pollution. Although there have been various control strategies implemented since 1998, there are still episodes of PM2.5 concentrations of hundreds of micrograms per cubic meter. In this study, samples were collected over a year in Beijing, chemically characterized, and the resulting data analyzed for source apportionment. The new error analysis capabilities built into EPA PMF V5.0 have been employed to better evaluate the profiles and assign them to source types. Secondary sulfate, local coal combustion and secondary nitrate were the major contributors to the PM2.5 mass. However, in this study, traffic was found to be more important as a PM compared to prior studies. It was actually the largest PM2.5 source in autumn and winter although local coal combustion is also a large source of PM in the winter months. These results demonstrate the value of using the displacement method to assess the variability in source profiles to improve our interpretation of PMF results. They also suggest more attention needs to be paid to traffic emissions in Beijing.

  19. “APEC Blue”: Secondary Aerosol Reductions from Emission Controls in Beijing

    PubMed Central

    Sun, Yele; Wang, Zifa; Wild, Oliver; Xu, Weiqi; Chen, Chen; Fu, Pingqing; Du, Wei; Zhou, Libo; Zhang, Qi; Han, Tingting; Wang, Qingqing; Pan, Xiaole; Zheng, Haitao; Li, Jie; Guo, Xiaofeng; Liu, Jianguo; Worsnop, Douglas R.

    2016-01-01

    China implemented strict emission control measures in Beijing and surrounding regions to ensure good air quality during the 2014 Asia-Pacific Economic Cooperation (APEC) summit. We conducted synchronous aerosol particle measurements with two aerosol mass spectrometers at different heights on a meteorological tower in urban Beijing to investigate the variations in particulate composition, sources and size distributions in response to emission controls. Our results show consistently large reductions in secondary inorganic aerosol (SIA) of 61–67% and 51–57%, and in secondary organic aerosol (SOA) of 55% and 37%, at 260 m and ground level, respectively, during the APEC summit. These changes were mainly caused by large reductions in accumulation mode particles and by suppression of the growth of SIA and SOA by a factor of 2–3, which led to blue sky days during APEC commonly referred to as “APEC Blue”. We propose a conceptual framework for the evolution of primary and secondary species and highlight the importance of regional atmospheric transport in the formation of severe pollution episodes in Beijing. Our results indicate that reducing the precursors of secondary aerosol over regional scales is crucial and effective in suppressing the formation of secondary particulates and mitigating PM pollution. PMID:26891104

  20. Variation of ambient carbonyl levels in urban Beijing between 2005 and 2012

    NASA Astrophysics Data System (ADS)

    Chen, Wentai; Shao, Min; Wang, Ming; Lu, Sihua; Liu, Ying; Yuan, Bin; Yang, Yudong; Zeng, Limin; Chen, Zhongming; Chang, Chih-Chung; Zhang, Qian; Hu, Min

    2016-03-01

    Carbonyl compounds are important precursors of secondary air pollutants. With the rapid economic development and the implementation of stricter control measures in Beijing, the sources of carbonyls possibly changed. Based on measurement data obtained at an urban site in Beijing between 2005 and 2012, we investigated annual variations in carbonyl levels and sources during these years. In summer, formaldehyde and acetaldehyde levels decreased significantly at a rate of 9.1%/year and 7.2%/year, respectively, while acetone levels increased at a rate of 4.3%/year. In winter, formaldehyde levels increased and acetaldehyde levels decreased. We also investigated the factors driving the variation in carbonyls levels during summer by determination of emission ratios for carbonyls and their precursors, and calculation of photochemical formation of carbonyls. The relative declines for primary formaldehyde and acetaldehyde levels were larger than those for secondary formation. This is possibly due to the increasing usage of natural gas and liquefied petroleum gas which could result in the rise of carbonyl precursor emission ratios. The increase in acetone levels might be related to the rising solvent usage in Beijing during these years. The influences of these sources should be paid more attention in future research.

  1. Spatial Pattern Analysis of Heavy Metals in Beijing Agricultural Soils Based on Spatial Autocorrelation Statistics

    PubMed Central

    Huo, Xiao-Ni; Zhang, Wei-Wei; Sun, Dan-Feng; Li, Hong; Zhou, Lian-Di; Li, Bao-Guo

    2011-01-01

    This study explored the spatial pattern of heavy metals in Beijing agricultural soils using Moran’s I statistic of spatial autocorrelation. The global Moran’s I result showed that the spatial dependence of Cr, Ni, Zn, and Hg changed with different spatial weight matrixes, and they had significant and positive global spatial correlations based on distance weight. The spatial dependence of the four metals was scale-dependent on distance, but these scale effects existed within a threshold distance of 13 km, 32 km, 50 km, and 29 km, respectively for Cr, Ni, Zn, and Hg. The maximal spatial positive correlation range was 57 km, 70 km, 57 km, and 55 km for Cr, Ni, Zn, and Hg, respectively and these were not affected by sampling density. Local spatial autocorrelation analysis detected the locations of spatial clusters and spatial outliers and revealed that the pollution of these four metals occurred in significant High-high spatial clusters, Low-high, or even High-low spatial outliers. Thus, three major areas were identified and should be receiving more attention: the first was the northeast region of Beijing, where Cr, Zn, Ni, and Hg had significant increases. The second was the southeast region of Beijing where wastewater irrigation had strongly changed the content of metals, particularly of Cr and Zn, in soils. The third area was the urban fringe around city, where Hg showed a significant increase. PMID:21776217

  2. Retrieval of CHOCHO from MAX-DOAS measurements in the Beijing area

    NASA Astrophysics Data System (ADS)

    Hendrick, Francois; Lerot, Christophe; Stavrakou, Trissevgeni; De Smedt, Isabelle; Fayt, Caroline; Gielen, Clio; Hermans, Christian; Müller, Jean-Francois; Pinardi, Gaia; Van Roozendael, Michel

    2015-04-01

    Glyoxal (CHOCHO) is one of the most important carbonyl compounds in the atmosphere. It is produced mainly by the oxidation of biogenic and anthropogenic non-methane volatile organic compounds (NMVOCs) which participate to the formation of tropospheric ozone and secondary organic aerosols. CHOCHO is also directly released by biomass burning and fossil fuel combustion. Measuring this species is therefore of major importance for air quality monitoring, especially given the scarcity of available CHOCHO observational data sets. In this presentation, CHOCHO vertical profiles and corresponding column densities are retrieved from MAX-DOAS measurements in the Beijing city center and at the suburban site of Xianghe located at 60km East of Beijing. The periods covered by the observations are June 2008-April 2009 in Beijing and March 2010-December 2014 in Xianghe. We first investigate the capability of the MAX-DOAS technique to measure this species in such highly-polluted environment. Then the diurnal and seasonal cycles of CHOCHO near-surface concentrations and vertical column densities as well as the corresponding CHOCHO/HCHO ratios are examined on a long-term basis at both locations. The CHOCHO/HCHO ratios are derived from MAX-DOAS HCHO vertical profiles retrieved in parallel to the CHOCHO profiles. These diurnal and seasonal cycles are further assessed using simulations from the 3D-CTM IMAGES and observations from the OMI and GOME-2 satellite nadir instruments. The impact of these results on our knowledge about the CHOCHO budget is discussed.

  3. [Assessing PM10 and SO2 networks using positive matrix factorization in Beijing city].

    PubMed

    Gao, Tao; Xie, Shao-dong; Bo, Yu; Zhao, Yue

    2010-03-01

    The aim of this study was to identify city areas with similar air pollution characteristics and determine which sites may be providing redundant information. Positive matrix factorization (PMF) was applied in this study to assess the mass concentrations of sulfur dioxide (SO2) and particulate matter with an aerodynamic diameter less than 10 microm (PM010), collected in the air quality monitoring network in the year of 2000. The analysis indicated that there were obviously seasonal variations for PM10 and SO2 in Beijing. The PM10 concentrations were higher in spring and lower in summer, but the SO2 concentrations were higher in winter and lower in summer. The results of the PMF showed that the sites of PM10 network in Beijing could be identified as three regions, which represented city areas characterized by the same specific air pollution. These three regions represented Gucheng site/Chegongzhuang site, Qianmen site/National Olympic Sports Center site/Tiantan site/Nongzhanguan site, and Ming Tombs site, respectively. Some sites in region 2 which included four sites may be redundant and can be removed. SO2 network can be divided into six regions including Chegongzhuang site/Qianmen site, Tiantan site/Nongzhanguan stie, Ming Tombs site, National Olympic Sports Center site, Dongsi site, and Gucheng site. It indicated that some sites in Beijing PM10 and SO2 monitoring networks might be redundant and could be removed or relocated to other areas. PMID:20358808

  4. Atmospheric particulate mercury in the megacity Beijing: Spatio-temporal variations and source apportionment

    NASA Astrophysics Data System (ADS)

    Schleicher, N. J.; Schäfer, J.; Blanc, G.; Chen, Y.; Chai, F.; Cen, K.; Norra, S.

    2015-05-01

    Particulate mercury (HgP) concentrations in weekly aerosol samples (PM2.5 and TSP) from Beijing, China, were measured for a complete year. In addition, spatial differences were measured for a shorter time period at four different sites and potential source materials were analyzed. Average HgP concentrations in PM2.5 samples were 0.26 ng/m3 for day-time PM2.5, 0.28 ng/m3 for night-time PM2.5, and 0.57 ng/m3 for TSP samples, respectively. Coal combustion was identified as the major source of HgP in Beijing. Other sources included industrial activities as well as red color on historical buildings as a minor contribution. Spatial differences were pronounced with highest concentrations in the inner city (inside the 3rd ring road). The results further showed a strong seasonality with highest concentrations in winter and lowest in summer due to local meteorological conditions (precipitation in summer and stagnant conditions and low mixing layer height in winter) as well as seasonal sources, such as coal combustion for heating purposes. Day-night differences also showed a seasonal pattern with higher night-time concentrations during summer and higher day-time concentrations during winter. Compared to other cities worldwide, the HgP concentrations in Beijing were alarmingly high, suggesting that airborne particulate Hg should be the focus of future monitoring activities and mitigation measures.

  5. Using stable isotopes to trace sources and formation processes of sulfate aerosols from Beijing, China.

    PubMed

    Han, Xiaokun; Guo, Qingjun; Liu, Congqiang; Fu, Pingqing; Strauss, Harald; Yang, Junxing; Hu, Jian; Wei, Lianfang; Ren, Hong; Peters, Marc; Wei, Rongfei; Tian, Liyan

    2016-01-01

    Particulate pollution from anthropogenic and natural sources is a severe problem in China. Sulfur and oxygen isotopes of aerosol sulfate (δ(34)Ssulfate and δ(18)Osulfate) and water-soluble ions in aerosols collected from 2012 to 2014 in Beijing are being utilized to identify their sources and assess seasonal trends. The mean δ(34)S value of aerosol sulfate is similar to that of coal from North China, indicating that coal combustion is a significant contributor to atmospheric sulfate. The δ(34)Ssulfate and δ(18)Osulfate values are positively correlated and display an obvious seasonality (high in winter and low in summer). Although an influence of meteorological conditions to this seasonality in isotopic composition cannot be ruled out, the isotopic evidence suggests that the observed seasonality reflects temporal variations in the two main contributions to Beijing aerosol sulfate, notably biogenic sulfur emissions in the summer and the increasing coal consumption in winter. Our results clearly reveal that a reduction in the use of fossil fuels and the application of desulfurization technology will be important for effectively reducing sulfur emissions to the Beijing atmosphere. PMID:27435991

  6. “APEC Blue”: Secondary Aerosol Reductions from Emission Controls in Beijing

    NASA Astrophysics Data System (ADS)

    Sun, Yele; Wang, Zifa; Wild, Oliver; Xu, Weiqi; Chen, Chen; Fu, Pingqing; Du, Wei; Zhou, Libo; Zhang, Qi; Han, Tingting; Wang, Qingqing; Pan, Xiaole; Zheng, Haitao; Li, Jie; Guo, Xiaofeng; Liu, Jianguo; Worsnop, Douglas R.

    2016-02-01

    China implemented strict emission control measures in Beijing and surrounding regions to ensure good air quality during the 2014 Asia-Pacific Economic Cooperation (APEC) summit. We conducted synchronous aerosol particle measurements with two aerosol mass spectrometers at different heights on a meteorological tower in urban Beijing to investigate the variations in particulate composition, sources and size distributions in response to emission controls. Our results show consistently large reductions in secondary inorganic aerosol (SIA) of 61-67% and 51-57%, and in secondary organic aerosol (SOA) of 55% and 37%, at 260 m and ground level, respectively, during the APEC summit. These changes were mainly caused by large reductions in accumulation mode particles and by suppression of the growth of SIA and SOA by a factor of 2-3, which led to blue sky days during APEC commonly referred to as “APEC Blue”. We propose a conceptual framework for the evolution of primary and secondary species and highlight the importance of regional atmospheric transport in the formation of severe pollution episodes in Beijing. Our results indicate that reducing the precursors of secondary aerosol over regional scales is crucial and effective in suppressing the formation of secondary particulates and mitigating PM pollution.

  7. Haze detection by using modified normalized difference haze index in Beijing, Tianjin, and Hebei province

    NASA Astrophysics Data System (ADS)

    Han, Xinlei; Yao, Fengmei; Zhang, Jiahua; Waqar, Mirza Muhammad; Zha, Yong; He, Junliang

    2016-04-01

    This paper presents the development of index to detect haze from moderate resolution imaging spectroradiometer remote sensing data. Detection of haze over a large area has always been a problem. This study focuses on Beijing, Tianjin, and Shijiazhuang cities in China. These cities have suffered the worst hazy weather in recent years. The spectral influence of haze on surface features was determined through analysis of the spectral variations of surface covers between hazy and haze-free days. A spectral index known as modified normalized difference haze index (m-NDHI) is developed that can be used to monitor haze distribution and intensity. Correlation analysis of the derived m-NDHI and previously developed NDHI with in situ PM2.5 (particulate matter with diameter <2.5 μm) data reveals that m-NDHI over water bodies has a coefficient of 0.7096, 0.5864, and 0.4857 and NDHI has coefficient of 0.5625, 0.5321, and 0.4618 with PM2.5 for Beijing, Tianjin, and Shijiazhuang, respectively, in winter. Moreover, the correlation of m-NDHI with PM2.5 is 0.4097, 0.8092, and 0.5546 during the spring, summer, and autumn, respectively, in Beijing. This developed index can be a much easier and more effective method to detect haze in large scales from remotely sensing data and characterize the situation of urban atmospheric pollution.

  8. [Assessment of ecological environment benefits of reclaimed water reuse in Beijing].

    PubMed

    Fan, Yu-Peng; Chen, Wei-Ping

    2014-10-01

    With the rapid development of the social economy and the sustained growth of population, China is facing increasingly serious water problems, and reclaimed water utilization has become an effective measure to solve water shortage problem and to control further deterioration of the ecological environment. Reclaimed water utilization can not only save a lot of fresh water, but also reduce the environmental impact of wastewater discharge, and thus has great ecological environmental benefits, including resource, environmental and human health benefits and so on. This study used the opportunity cost method to construct an evaluation system for ecological environmental benefits of reclaimed water utilization, and Beijing was taken as an example to conduct an estimation of ecological environmental benefits of reclaimed water utilization. Research results indicated that the reclaimed water utilization in Beijing had considerable environmental benefits for ¥ 1.2 billion in 2010, in which replacement of fresh water accounted for the largest share. The benefits of environmental improvement and groundwater recharge were large, while the other benefits were small or negative. The ecological environment benefits of reclaimed water utilization in Beijing was about 1.8 times that of its direct economic benefits, showing that reclaimed water utilization was in accordance with sustainable development. Related methods and results will provide scientific basis to promote the development of reclaimed water utilization in our country. PMID:25693414

  9. Using stable isotopes to trace sources and formation processes of sulfate aerosols from Beijing, China

    NASA Astrophysics Data System (ADS)

    Han, Xiaokun; Guo, Qingjun; Liu, Congqiang; Fu, Pingqing; Strauss, Harald; Yang, Junxing; Hu, Jian; Wei, Lianfang; Ren, Hong; Peters, Marc; Wei, Rongfei; Tian, Liyan

    2016-07-01

    Particulate pollution from anthropogenic and natural sources is a severe problem in China. Sulfur and oxygen isotopes of aerosol sulfate (δ34Ssulfate and δ18Osulfate) and water-soluble ions in aerosols collected from 2012 to 2014 in Beijing are being utilized to identify their sources and assess seasonal trends. The mean δ34S value of aerosol sulfate is similar to that of coal from North China, indicating that coal combustion is a significant contributor to atmospheric sulfate. The δ34Ssulfate and δ18Osulfate values are positively correlated and display an obvious seasonality (high in winter and low in summer). Although an influence of meteorological conditions to this seasonality in isotopic composition cannot be ruled out, the isotopic evidence suggests that the observed seasonality reflects temporal variations in the two main contributions to Beijing aerosol sulfate, notably biogenic sulfur emissions in the summer and the increasing coal consumption in winter. Our results clearly reveal that a reduction in the use of fossil fuels and the application of desulfurization technology will be important for effectively reducing sulfur emissions to the Beijing atmosphere.

  10. Ambient concentrations of aldehydes in relation to Beijing Olympic air pollution control measures

    NASA Astrophysics Data System (ADS)

    Gong, J. C.; Zhu, T.; Hu, M.; Zhang, L. W.; Cheng, H.; Zhang, L.; Tong, J.; Zhang, J.

    2010-08-01

    Aldehydes are ubiquitous constituents of the atmosphere. Their concentrations are elevated in polluted urban atmospheres. The present study was carried out to characterize three aldehydes of most health concern (formaldehyde, acetaldehyde, and acrolein) in a central Beijing site in the summer and early fall of 2008 (from June to October). Measurements were made before, during, and after the Beijing Olympics to examine whether the air pollution control measures implemented to improve Beijing's air quality during the Olympics had any impact on concentrations of the three aldehydes. Average concentrations of formaldehyde, acetaldehyde and acrolein were 29.34 ± 15.12 μg/m3, 27.09 ± 15.74 μg/m3 and 2.32 ± 0.95 μg/m3, respectively, for the entire period of measurements, all being the highest among the levels measured in cities around the world in photochemical smog seasons. Among the three measured aldehydes, only acetaldehyde had a substantially reduced mean concentration during the Olympic air pollution control period compared to the pre-Olympic period. Formaldehyde and acrolein followed the changing pattern of temperature and were each significantly correlated with ozone (a secondary product of photochemical reactions). In contrast, acetaldehyde was significantly correlated with several pollutants emitted mainly from local emission sources (e.g., NO2, CO, and PM2.5). These findings suggest that local direct emissions had a larger impact on acetaldehyde than formaldehyde and acrolein.

  11. Chemical characterization and source apportionment of PM2.5 in Beijing: seasonal perspective

    NASA Astrophysics Data System (ADS)

    Zhang, R.; Jing, J.; Tao, J.; Hsu, S.-C.; Wang, G.; Cao, J.; Lee, C. S. L.; Zhu, L.; Chen, Z.; Zhao, Y.; Shen, Z.

    2013-07-01

    In this study, 121 daily PM2.5 (aerosol particle with aerodynamic diameter less than 2.5 μm) samples were collected from an urban site in Beijing in four months between April 2009 and January 2010 representing the four seasons. The samples were determined for various compositions, including elements, ions, and organic/elemental carbon. Various approaches, such as chemical mass balance, positive matrix factorization (PMF), trajectory clustering, and potential source contribution function (PSCF), were employed for characterizing aerosol speciation, identifying likely sources, and apportioning contributions from each likely source. Our results have shown distinctive seasonality for various aerosol speciations associated with PM2.5 in Beijing. Soil dust waxes in the spring and wanes in the summer. Regarding the secondary aerosol components, inorganic and organic species may behave in different manners. The former preferentially forms in the hot and humid summer via photochemical reactions, although their precursor gases, such as SO2 and NOx, are emitted much more in winter. The latter seems to favorably form in the cold and dry winter. Synoptic meteorological and climate conditions can overwhelm the emission pattern in the formation of secondary aerosols. The PMF model identified six main sources: soil dust, coal combustion, biomass burning, traffic and waste incineration emission, industrial pollution, and secondary inorganic aerosol. Each of these sources has an annual mean contribution of 16, 14, 13, 3, 28, and 26%, respectively, to PM2.5. However, the relative contributions of these identified sources significantly vary with changing seasons. The results of trajectory clustering and the PSCF method demonstrated that regional sources could be crucial contributors to PM pollution in Beijing. In conclusion, we have unraveled some complex aspects of the pollution sources and formation processes of PM2.5 in Beijing. To our knowledge, this is the first systematic study

  12. Variation of ambient non-methane hydrocarbons in Beijing city in summer 2008

    NASA Astrophysics Data System (ADS)

    Wang, B.; Shao, M.; Lu, S. H.; Yuan, B.; Zhao, Y.; Wang, M.; Zhang, S. Q.; Wu, D.

    2010-02-01

    In conjunction with hosting the 2008 Beijing Olympics, the municipal government implemented a series of stringent air quality control measures. To assess the impacts on variation of ambient non-methane hydrocarbons (NMHCs), the whole air was sampled by canisters at one urban site and two suburban sites in Beijing, and 55 NMHC species were quantified by gas chromatography equipped with a quadrupole mass spectrometer and a flame ionization detector (GC/MSD/FID) as parts of the field Campaign for the Beijing Olympic Games Air Quality program (CareBeijing). According to the control measures, the data were presented according to four periods: 18-30 June, 8-19 July, 15-24 August (during the Olympic Games), and 6-15 September (during the Paralympic Games). Compared with the levels in June, the mixing ratios of NMHCs obtained in the Olympic and Paralympic Games periods were reduced by 35% and 25%, respectively. Source contributions were calculated using a chemical mass balance model (CMB 8.2). After implementing the control measures, emissions from target sources were obviously reduced, and reductions in vehicle exhaust could explain 48-82% of the reductions of ambient NMHCs. Reductions in emissions from gasoline evaporation, paint and solvent use, and the chemical industry contributed 9-40%, 3-24%, and 1-5%, respectively, to reductions of ambient NMHCs. Sources of liquefied petroleum gas (LPG) and biogenic emissions were not controlled, and contributions from these sources from July to September were stable or even higher than in June. Ozone formation potentials (OFPs) were calculated for the measured NMHCs. The total OFPs during the Olympic and Paralympic Games were reduced by 48% and 32%, respectively, compared with values in June. Reductions in the OFPs of alkenes and aromatics explained 77-92% of total OFP reductions. The alkenes and aromatics were mainly from vehicle exhausts, and reductions of vehicle exhaust gases explained 67-87% of reductions in alkenes and 38

  13. Variation of ambient non-methane hydrocarbons in Beijing city in summer 2008

    NASA Astrophysics Data System (ADS)

    Wang, B.; Shao, M.; Lu, S. H.; Yuan, B.; Zhao, Y.; Wang, M.; Zhang, S. Q.; Wu, D.

    2010-07-01

    In conjunction with hosting the 2008 Beijing Olympics, the municipal government implemented a series of stringent air quality control measures. To assess the impacts on variation of ambient non-methane hydrocarbons (NMHCs), the whole air was sampled by canisters at one urban site and two suburban sites in Beijing, and 55 NMHC species were quantified by gas chromatography equipped with a quadrupole mass spectrometer and a flame ionization detector (GC/MSD/FID) as parts of the field Campaign for the Beijing Olympic Games Air Quality program (CareBeijing). According to the control measures, the data were presented according to four periods: 18-30 June, 8-19 July, 15-24 August (during the Olympic Games), and 6-15 September (during the Paralympic Games). Compared with the levels in June, the mixing ratios of NMHCs obtained in the Olympic and Paralympic Games periods were reduced by 35% and 25%, respectively. Source contributions were calculated using a chemical mass balance model (CMB 8.2). After implementing the control measures, emissions from target sources were obviously reduced, and reductions in vehicle exhaust could explain 48-82% of the reductions of ambient NMHCs. Reductions in emissions from gasoline evaporation, paint and solvent use, and the chemical industry contributed 9-40%, 3-24%, and 1-5%, respectively, to reductions of ambient NMHCs. Sources of liquefied petroleum gas (LPG) and biogenic emissions were not controlled, and contributions from these sources from July to September were stable or even higher than in June. Ozone formation potentials (OFPs) were calculated for the measured NMHCs. The total OFPs during the Olympic and Paralympic Games were reduced by 48% and 32%, respectively, compared with values in June. Reductions in the OFPs of alkenes and aromatics explained 77-92% of total OFP reductions. The alkenes and aromatics were mainly from vehicle exhausts, and reductions of vehicle exhaust gases explained 67-87% of reductions in alkenes and 38

  14. Air quality during the 2008 Beijing Olympics: secondary pollutants and regional impact

    NASA Astrophysics Data System (ADS)

    Wang, T.; Nie, W.; Gao, J.; Xue, L. K.; Gao, X. M.; Wang, X. F.; Qiu, J.; Poon, C. N.; Meinardi, S.; Blake, D.; Wang, S. L.; Ding, A. J.; Chai, F. H.; Zhang, Q. Z.; Wang, W. X.

    2010-08-01

    This paper presents the first results of the measurements of trace gases and aerosols at three surface sites in and outside Beijing before and during the 2008 Olympics. The official air pollution index near the Olympic Stadium and the data from our nearby site revealed an obvious association between air quality and meteorology and different responses of secondary and primary pollutants to the control measures. Ambient concentrations of vehicle-related nitrogen oxides (NOx) and volatile organic compounds (VOCs) at an urban site dropped by 25% and 20-45% in the first two weeks after full control was put in place, but the levels of ozone, sulfate and nitrate in PM2.5 increased by 16%, 64%, 37%, respectively, compared to the period prior to the full control; wind data and back trajectories indicated the contribution of regional pollution from the North China Plain. Air quality (for both primary and secondary pollutants) improved significantly during the Games, which were also associated with the changes in weather conditions (prolonged rainfall, decreased temperature, and more frequent air masses from clean regions). A comparison of the ozone data at three sites on eight ozone-pollution days, when the air masses were from the southeast-south-southwest sector, showed that regional pollution sources contributed >34-88% to the peak ozone concentrations at the urban site in Beijing. Regional sources also contributed significantly to the CO concentrations in urban Beijing. Ozone production efficiencies at two sites were low (~3 ppbv/ppbv), indicating that ozone formation was being controlled by VOCs. Compared with data collected in 2005 at a downwind site, the concentrations of ozone, sulfur dioxide (SO2), total sulfur (SO2+PM2.5 sulfate), carbon monoxide (CO), reactive aromatics (toluene and xylenes) sharply decreased (by 8-64%) in 2008, but no significant changes were observed for the concentrations of PM2.5, fine sulfate, total odd reactive nitrogen (NOy), and longer

  15. Modern Tectonic Deformation in the Active Basin-And Province Northwest of Beijing, China

    NASA Astrophysics Data System (ADS)

    Mi, S.; Wen, X.

    2012-12-01

    Our study region is the northwest of Beijing, northern north China. The most typical extensional active tectonic area of the China continent, called the active basin-and-range province northwest of Beijing, exist there. This active tectonic province is made up of several NE-trending Quaternary graben basins and horst ranges between basins. An about 1500-year-long written historical record has suggested that there have been no major earthquakes with magnitude 7 or greater occurred in most of the study region since AD 512. So, the characteristic of modern tectonic deformation of the study region and its implication for the future seismic potential of major earthquakes are important scientific issues. In this study, based on data of regional GPS station velocities and active tectonics, combining relocated earthquake distribution, we make a preliminary analysis on the characteristic of the modern tectonic deformation of the study region. We design three zones across deferent segments of the active basin-and-range province to analyze both the present tectonic deformation from the GPS velocity profiles and the major fault's downward-extents from the relocated hypocenters. Our analyses reveal that: (1) Significant NNW-ward and SSE-ward horizontal extension exists on different segments of the active basin-and-range province northwest of Beijing at rates of 2 to 3mm /yr, accompanied with right-lateral shear deformation at 1 to 2mm/yr. (2) On the present tectonic deformation, the southeastern margin of the Datong-Yangyuan basin, the biggest graben basin of the active tectonic province, shows as a turning belt of the extensional rates, suggesting that relatively high tensile strain accumulation could exist there. (3)On the northeastern segment of the studied active basin-and-range province, both the Zhangjiakou-Yanhui graben basin and the Beijing graben basin have also been being in significant extensional and shear deformation. (4) The relocated hypocenter distribution have

  16. On-road emission factor distributions of individual diesel vehicles in and around Beijing, China

    NASA Astrophysics Data System (ADS)

    Wang, Xing; Westerdahl, Dane; Wu, Ye; Pan, Xiaochuan; Zhang, K. Max

    2011-01-01

    This paper reports findings of a recent field study that characterized the on-road emissions of individual diesel vehicles in and around Beijing, China during November and December of 2009. We successfully sampled 230 individual trucks on 4 major expressways around the city as well as 57 individual buses in the city using refined mobile chasing techniques and fast response instruments. Emission factors (EF) for carbon monoxide (CO), black carbon (BC) and particulate matter with diameters less than 0.5 μm (PM 0.5) are derived from the measurements, which are consistent with the results from laboratory dynamometer tests. The PM 0.5 number emission factor distributions demonstrate consistent bimodal modes with peaks around 10 nm and 80 nm, while the mass emission factor distributions demonstrate a unimodal maximum around 110 nm for a majority of the trucks. The BC emissions are shown to be highly correlated with the mass emission of particles with 100-250 nm diameters, which are in good agreement with the results from previous studies. A number of important policy implications are discussed based on the results from this study. First, we identified "heavy emitters" in the on-road fleet we encountered, finding that 5% of diesel trucks in this sample are responsible for 50% of total BC emissions, and 20% of the trucks are responsible for 50% CO and PM 0.5 number emissions, 60% PM 0.5 mass emissions and over 70% of BC emissions. This suggests that emissions control programs should include identifying and removing heavy emitters from the road or improving their emissions. Second, the BC and PM 0.5 number emission factors of trucks registered in regions outside Beijing are significantly higher than those of Beijing-registered trucks, suggesting that improving engine and fuel standards in Beijing alone is not sufficient in reducing the traffic-related air pollution in Beijing. Third, the significantly lower emissions from Euro IV and CNG buses compared to the Euro II and

  17. A comparative study on women's employment in Beijing, Guangzhou and Hong Kong.

    PubMed

    Liu, X

    1992-01-01

    A comparison of the female population in different social systems and different socioeconomic levels was conducted for Beijing, Guangzhou, and Hong Kong between September 1988 and October 1990. The women's federations in Beijing and Guangzhou and the University of Hong Kong performed the sample survey of 12 occupations in China and Hong Kong. The assumption was that the process of women's emancipation was accelerated when material conditions and culture were well-developed. The differences in employment patterns in the three cities are presented followed by a discussion of the motives for employment. Differences in their attachment to the traditional role of women were evident; most expressed the importance of work and family and the desire to be successful in life and career. Differences were also evident in women's expectation of the role of government in having responsibility for women's employment and priorities. The reports from women in Beijing and Guangzhou expressed difficulty in locating a job and lack of information on job availabilities. Hong Kong is different from the other cities in that the supply of workers is less than the demand. Only through productivity increases can women have a brighter prospect for employment. There was a high level of agreement that the reasons for employment are increased income and economic independence. The third factor of importance was "self-realization", and over 90% in all three cities reported that employment would continue if other family members could support the family. Women strongly agreed that success was achieved through extra effort, and wished for the same opportunity for promotion which the men enjoyed. The traditional role of women giving priority to their families was strongest in Hong Kong. 45% of women in Hong Kong agreed that women should avoid being more successful in work than their husbands, while only 13.4% in Beijing agreed. Women in Beijing and Guangzhou expected government to other relevant

  18. Seasonal trends in PM2.5 source contributions in Beijing, China

    NASA Astrophysics Data System (ADS)

    Zheng, Mei; Salmon, Lynn G.; Schauer, James J.; Zeng, Limin; Kiang, C. S.; Zhang, Yuanhang; Cass, Glen R.

    The 24-h PM2.5 samples (particles with an aerodynamic diameter of 2.5 μm or less) were taken at 6-day intervals at five urban and rural sites simultaneously in Beijing, China for 1 month in each quarter of calendar year 2000. Samples at each site were combined into a monthly composite for the organic tracer analysis by GC/MS (gas chromatography/mass spectrometry). Compared to the data obtained from other metropolitan cities in the US, the PM2.5 mass and fine organic carbon (OC) concentrations in Beijing were much higher with an annual average of 101 and 20.9 μg m -3, respectively. Over one hundred organic compounds including unique tracers for important sources were quantified in PM2.5 in Beijing. Source apportionment of fine OC was conducted using chemical mass balance receptor model (CMB) in combination with particle-phase organic compounds as fitting tracers. Carbonaceous aerosols and major ions (sulfate, nitrate and ammonium) constituted 69% of PM2.5 mass on average. The major sources of PM2.5 mass in Beijing averaged over five sites on an annual basis were determined as dust (20%), secondary sulfate (17%), secondary nitrate (10%), coal combustion (7%), diesel and gasoline exhaust (7%), secondary ammonium (6%), biomass aerosol (6%), cigarette smoke (1%), and vegetative detritus (1%). The lowest PM2.5 mass concentration was found in January (60.9 μg m -3), but the contribution of carbonaceous aerosol to PM2.5 mass was maximal during this season, accounting for 57% of the mass. During cold heating season, the contributions from coal combustion and biomass aerosol to PM2.5 mass increased, accounting for 20.9% of fine particle mass in October and 24.5% in January. The contribution of the biomass aerosols peaked in the fall. In April 2000, the impact of dust storms was so significant that dust alone constituted 36% of PM2.5 mass. On average, the model resolved 88% of the sources of the PM2.5 mass concentrations in Beijing.

  19. Long term PM2.5 estimation and its impact on human health in Beijing, China

    NASA Astrophysics Data System (ADS)

    Zheng, Sheng; Pozzer, Andrea; Cao, Chunxiang

    2014-05-01

    Due to the economic growth and urbanization, the emissions of pollutants have increased significantly in the North China Plain (NCP). Beijing, the capital of China, is located at the northern tip of NCP, and it is considered one of the most densely populated cities with the poorest air quality. This is of major concerns, because of the impact of high pollutants concentration on human health. The present study analyses the characteristics of AOD and the particulate matter with diameter < 2.5 μm (PM2.5) and its impact on human health in the central Beijing areas. We acquire AOD from Aerosol Robotic Network (AERONET) in Beijing from 2001 to 2012. The AOD data are fitted with a lognormal distribution, and the 95% of the cumulative probability is used as the threshold for episodes of high AOD. Most episodes occur in summer, mostly in June, though this is combined with high precipitation. Episodes of high AOD caused by coarse pollutants occur only in March and April, and they are mostly caused by dust from the north. According to wind direction, wind speed, boundary layer height (BLH) and pollutant emission distribution, episodes of high AOD are due to the anthropogenic pollutants from the south (Hebei province). Based on ground PM2.5 observation from the US embassy in Beijing from 2010 to 2011, we establish a relationship between PM2.5and AERONET AOD, including BLH and relative humidity (RH) correction. Thanks to this method, 12 years of PM2.5 are estimated for the Beijing central area, allowing the estimation of long term concentrations of this pollutant. Since there is no obvious difference among the daily PM2.5 of six stations lying in Chaoyang, Dongcheng, and Xicheng district, we use the daily PM2.5 from US embassy station to represent the PM2.5 concentration in these three districts, and calculate yearly premature mortality due to long term exposure to PM2.5among the population with an age of ≥ 30 yr in these three districts.

  20. Source apportionment and air quality impact assessment studies in Beijing/China

    NASA Astrophysics Data System (ADS)

    Suppan, P.; Schrader, S.; Shen, R.; Ling, H.; Schäfer, K.; Norra, S.; Vogel, B.; Wang, Y.

    2012-04-01

    More than 15 million people in the greater area of Beijing are still suffering from severe air pollution levels caused by sources within the city itself but also from external impacts like severe dust storms and long range advection from the southern and central part of China. Within this context particulate matter (PM) is the major air pollutant in the greater area of Beijing (Garland et al., 2009). PM did not serve only as lead substance for air quality levels and therefore for adverse health impact effects but also for a strong influence on the climate system by changing e.g. the radiative balance. Investigations on emission reductions during the Olympic Summer Games in 2008 have caused a strong reduction on coarser particles (PM10) but not on smaller particles (PM2.5). In order to discriminate the composition of the particulate matter levels, the different behavior of coarser and smaller particles investigations on source attribution, particle characteristics and external impacts on the PM levels of the city of Beijing by measurements and modeling are performed: Examples of long term measurements of PM2.5 filter sampling in 2005 with the objectives of detailed chemical (source attribution, carbon fraction, organic speciation and inorganic composition) and isotopic analyses as well as toxicological assessment in cooperation with several institutions (Karlsruhe Institute of Technology (IfGG/IMG), Helmholtz Zentrum München (HMGU), University Rostock (UR), Chinese University of Mining and Technology Beijing, CUMTB) will be discussed. Further experimental studies include the operation of remote sensing systems to determine continuously the MLH (by a ceilometer) and gaseous air pollutants near the ground (by DOAS systems) as well as at the 320 m measurement tower (adhesive plates at different heights for passive particle collection) in cooperation with the Institute of Atmospheric Physics (IAP) of the Chinese Academy of Sciences (CAS). The influence of the MLH on

  1. Etude de l'influence de la temperature et de l'humidite sur les proprietes mecaniques en traction des fibres de chanvre et de coco

    NASA Astrophysics Data System (ADS)

    Ho Thi, Thu Nga

    L'objectif de cette etude fut d'etablir l'effet de l'humidite et de la temperature sur la resistance en traction et le module elastique des fibres de chanvre et de coco. Deux etudes ont ete realisees afin d'atteindre cet objectif. La premiere vise l'absorption de l'humidite dans ces fibres en exposition dans l'air (de 0%RH a 80%RH) ainsi que l'absorption de l'eau dans ces fibres immergees dans l'eau aux differentes temperatures. La deuxieme consiste a mesurer la resistance en traction et le module elastique de ces fibres sous differentes conditions d'humidite et de temperature. En basant sur les resultats experimentaux obtenus, les methodes semi empiriques et de reseaux de neurones ont ete utilisees pour but de predire les proprietes en traction (resistance et module d'elasticite) des fibres de chanvre et de coco sous l'influence de l'humidite et de la temperature.

  2. Reductions of PM2.5 in Beijing-Tianjin-Hebei urban agglomerations during the 2008 Olympic Games

    NASA Astrophysics Data System (ADS)

    Xin, Jinyuan; Wang, Yuesi; Wang, Lili; Tang, Guiqian; Sun, Yang; Pan, Yuepeng; Ji, Dongsheng

    2012-11-01

    The Atmospheric Environmental Monitoring Network successfully undertook the task of monitoring the atmospheric quality of Beijing and its surrounding area during the 2008 Olympics. The results of this monitoring show that high concentrations of PM2.5 pollution exhibited a regional pattern during the monitoring period (1 June-30 October 2008). The PM2.5 mass concentrations were 53 μg m-3, 66 μg m-3, and 82 μg m-3 at the background site, in Beijing, and in the Beijing-Tianjin-Hebei urban agglomerations, respectively. The PM2.5 levels were lowest during the 2008 Olympic Games (8-24 August): 35 μg m-3 at the background site, 42 μg m-3 in Beijing and 57 μg m-3 in the region. These levels represent decreases of 49%, 48%, and 56%, respectively, compared to the prophase mean concentration before the Olympic Games. Emission control measures contributed 62%-82% of the declines observed in Beijing, and meteorological conditions represented 18%-38%. The concentration of fine particles met the goals set for a "Green Olympics."

  3. Etude des phenomenes dynamiques ultrarapides et des caracteristiques impulsionnelles d'emission terahertz du supraconducteur YBCO

    NASA Astrophysics Data System (ADS)

    Savard, Stephane

    Les premieres etudes d'antennes a base de supraconducteurs a haute temperature critique emettant une impulsion electromagnetique dont le contenu en frequence se situe dans le domaine terahertz remontent a 1996. Une antenne supraconductrice est formee d'un micro-pont d'une couche mince supraconductrice sur lequel un courant continu est applique. Un faisceau laser dans le visible est focalise sur le micro-pont et place le supraconducteur dans un etat hors-equilibre ou des paires sont brisees. Grace a la relaxation des quasiparticules en surplus et eventuellement de la reformation des paires supraconductrices, nous pouvons etudier la nature de la supraconductivite. L'analyse de la cinetique temporelle du champ electromagnetique emis par une telle antenne terahertz supraconductrice s'est averee utile pour decrire qualitativement les caracteristiques de celle-ci en fonction des parametres d'operation tels que le courant applique, la temperature et la puissance d'excitation. La comprehension de l'etat hors-equilibre est la cle pour comprendre le fonctionnement des antennes terahertz supraconductrices a haute temperature critique. Dans le but de comprendre ultimement cet etat hors-equilibre, nous avions besoin d'une methode et d'un modele pour extraire de facon plus systematique les proprietes intrinseques du materiau qui compose l'antenne terahertz a partir des caracteristiques d'emission de celle-ci. Nous avons developpe une procedure pour calibrer le spectrometre dans le domaine temporel en utilisant des antennes terahertz de GaAs bombarde aux protons H+ comme emetteur et detecteur. Une fois le montage calibre, nous y avons insere une antenne emettrice dipolaire de YBa 2Cu3O7-delta . Un modele avec des fonctions exponentielles de montee et de descente du signal est utilise pour lisser le spectre du champ electromagnetique de l'antenne de YBa 2Cu3O7-delta, ce qui nous permet d'extraire les proprietes intrinseques de ce dernier. Pour confirmer la validite du modele

  4. Aerosol chemistry in Beijing, China: Different pollution regimes and diurnal profiles

    NASA Astrophysics Data System (ADS)

    van Pinxteren, D.; Brüggemann, E.; Gnauk, T.; Iinuma, Y.; Müller, K.; Nowak, A.; Achtert, P.; Wiedensohler, A.; Herrmann, H.

    2009-04-01

    The rapid economic development during the last three decades in China has led to a severe decrease in air quality, especially in densely populated regions such as Beijing, Shanghai, and the Pearl River Delta. Although during last years a number of measures for air pollution control have been implemented especially in the capital Beijing, air pollution is still regarded to be one of the top environmental concerns in China during the next decade. To better characterize the processes leading to the frequently observed high concentrations of air pollutants on a regional scale, the international field campaign "Campaigns of Air Quality Research in Beijing 2006" (CAREBEIJING2006) was conducted in summer 2006. Organized by the Peking University, project partners from Japan, Korea, Hong Kong, Germany, and China studied the various aspects of gaseous and particulate air pollution in a megacity environment. In this contribution, we present chemical data of size-resolved particles, obtained by a 5-stage Berner impactor (0.05-10 μm) during 3 weeks at both an urban and a suburban site in the area of Beijing, China. The sampling time of the impactors was about 4-5 hours. This allowed for taking four size-resolved samples per day and obtaining rough diurnal profiles of particle components. The samples were analyzed for inorganic ions (Cl-, SO42-, NO3-, NH4+, K+, Ca2+, Na+, Mg2+), carbon sum parameters (OC, EC, WSOC), and a variety of organic compounds such as dicarboxylic acids, alkanes, PAHs and, for the first time in China, nitrooxy-organosulfates. On average, the observed PM10 mass concentrations were 133 μg m-3 and 112 μg m-3 at the urban and suburban site, respectively. In general, the observed concentrations of particulate pollutants were similarly high as reported from previous studies in the Beijing summer atmosphere. A back trajectory analysis allowed the classification of the samples into different meteorological categories with different air mass origins. A high

  5. Application of Microtremor Array Analysis to Estimate the Bedrock Depth in the Beijing Plain area

    NASA Astrophysics Data System (ADS)

    Xu, P.; Ling, S.; Liu, J.; Su, W.

    2013-12-01

    With the rapid expansion of large cities around the world, urban geological survey provides key information regarding resource development and urban construction. Among the major cities of the world, China's capital city Beijing is among the largest cities possessing complex geological structures. The urban geological survey and study in Beijing involves the following aspects: (1) estimating the thickness of the Cenozoic deposit; (2) mapping the three-dimensional structure of the underlying bedrock, as well as its relations to faults and tectonic settings; and (3) assessing the capacity of the city's geological resources in order to support its urban development and operation safety. The geological study of Beijing in general was also intended to provide basic data regarding the urban development and appraisal of engineering and environment geological conditions, as well as underground space resources. In this work, we utilized the microtremor exploration method to estimate the thickness of the bedrock depth, in order to delineate the geological interfaces and improve the accuracy of the bedrock depth map. The microtremor observation sites were located in the Beijing Plain area. Traditional geophysical or geological survey methods were not effective in these areas due to the heavy traffic and dense buildings in the highly-populated urban area. The microtremor exploration method is a Rayleigh-wave inversion technique which extracts its phase velocity dispersion curve from the vertical component of the microtremor array records using the spatial autocorrelation (SPAC) method, then inverts the shear-wave velocity structure. A triple-circular array was adopted for acquiring microtremor data, with the observation radius in ranging from 40 to 300 m, properly adjusted depending on the geological conditions (depth of the bedrock). The collected microtremor data are used to: (1) estimation of phase velocities of Rayleigh-wave from the vertical components of the microtremor

  6. Chemical characteristics of PM2.5 during haze episodes in Beijing

    NASA Astrophysics Data System (ADS)

    Shen, Rongrong; Schaefer, Klaus; Suppan, Peter; Wang, Yuesi; Schnelle-Kreis, Jürgen; Shao, Longyi; Emeis, Stefan

    2014-05-01

    Haze episodes have become much more frequent in Beijing and have received more attention during the past decade because of its influences on visibility and human health. Due to the chemical characteristics and sources of haze, which are different from the normal urban aerosols, studies of haze pollution become more important for the control of air pollution in Beijing. This study aims to investigate the chemical characteristics of PM2.5 during haze episodes in Beijing in 2013 spring and the possible sources of chemical compounds during haze episodes. Two sequential High-Volume Samplers (Digitel DHA-80, Hegnau, Switzerland) were used to collect PM2.5 samples in Beijing automatically from 10 April to 8 June 2013. The inorganic elements, inorganic water-soluble ions, EC and OC of PM2.5 were analyzed by ICP-MS, IC and thermal/optical carbon analyzers respectively. Three haze episodes were found: 18 to 25 April, 3 to 9 May and 1 to 8 June. The average PM2.5 mass concentration during haze days was 140 µg m-3 while 45 µg m-3 during clear days. SO42-, NO3-, NH4+, Cl-, K+, Cu, Ni, Zn, As, Cd, Tl, Pb, EC and OC, mass concentrations increased during haze days, compared with concentrations during clear days. The main increase is that secondary inorganic pollutant mass concentrations (NO3-, SO42- and NH4+) were 6 times higher and mass percentages were 2 times higher. This indicates that the major chemical species of PM2.5 during haze episodes are originated from anthropogenic sources. NO3-, SO42- and NH4+ are basically formed by a gas-to-particle formation processes on the basis of chemical reactions of precursor gases. Mass ratio of NO3-/SO42- is widely used as an indicator to determine the importance of mobile sources and stationary sources of sulphur and nitrogen. The mass ratio of NO3-/SO42- during haze days (0.82) was higher than during clear days (0.68) suggesting that vehicle emission is an important reason for haze in Beijing. OC/EC mass ratio higher than 2 indicates

  7. A Population-based Study of Invasive Cervical Cancer Patients in Beijing: 1993–2008

    PubMed Central

    Wang, Tong; Wu, Ming-Hui; Wu, Yu-Mei; Zhang, Wei-Yuan

    2015-01-01

    Background: In recent years, the incidence of cervical cancer has been rising, particularly in young adults, as the second most common gynecological cancer in China. The aim of this study was to explore the incidence change and the epidemiological characteristics of cervical cancer in Beijing over the past 16 years. Methods: All the cases of the study were limited to Beijing residents diagnosed with cervical cancer and registered in Beijing from January 1, 1993, to December 31, 2008. A total of 4100 patients with cervical cancer were obtained from the Statistics Database of Beijing Cancer Registry (BJCaR). According to the registered data, we retrospectively reviewed all original cases which we can acquired in reported hospital. Cervical situ cancer, cervical metastatic cancer, non-Beijing residents and repeatedly registered cases were excluded. Totally, 3641 registered cases were verified correctly. Meanwhile, we also collected the following data: Age, occupation, detected methods, histological type, and staging. The trends of incidence and mortality were analyzed by Joinpoint Regression Program 4.1.1.1 produced by National Cancer Institute (NCI, USA). The annual percent change (APC) was calculated using the Joinpoint regression model. Results: The crude rates of incidence and mortality were 10.4 and 1.0 per 100,000 women, respectively during 1993 to 2008. The average WHO age-standardized incidence rates were 11.5 per 100,000 women. There was a decrease in incidence annually by 8.0% (P = 0.3) during 1993–1996 and a rapid increase annually by 18.9% after 1999 (P < 0.01). The median age was 67 years in 1993, but the median age decreased to 45 years in 2008. The peak of the age-specific incidence curve was at 40 years in the most recent period (2005–2008), which was 25–30 years earlier than that in previous periods (1993–1996). In the 2224 cases, the numbers of patients with stage I, II, III and IV were 910 (40.9%), 601 (27%), 542 (24.4%), 171 (7

  8. O3, SO2, NO2, and UVB measurements in Beijing and Baseline Station of northwestern part of China

    NASA Technical Reports Server (NTRS)

    Guo, Song; Zhou, Xiuji; Zhang, Xiachun

    1994-01-01

    A MKII Brewer ozone spectrometer was used in Beijing from Oct. 1990 to June 1991 to measure O3, SO2 and UVB radiation. And since Nov. 1991 a new MKIV Brewer spectrometer, which can take the measurements of O3, SO2, NO2 and UVB radiation, has been set up in Beijing. The MKII Brewer spectrometer was moved to Qinghai baseline station which is on the Qinghai-tibetean plateau in the northwestern part of China. Both the data in Beijing and Qinghai baseline station has been analyzed and some results will be shown here along with the ozone profiles botained through the Umkehr program given by AES of Canada for the Brewer ozone spectrometer.

  9. Evaluation of High-Resolution Precipitation Estimates from Satellites during July 2012 Beijing Flood Event Using Dense Rain Gauge Observations

    PubMed Central

    Chen, Sheng; Liu, Huijuan; You, Yalei; Mullens, Esther; Hu, Junjun; Yuan, Ye; Huang, Mengyu; He, Li; Luo, Yongming; Zeng, Xingji; Tang, Guoqiang; Hong, Yang

    2014-01-01

    Satellite-based precipitation estimates products, CMORPH and PERSIANN-CCS, were evaluated with a dense rain gauge network over Beijing and adjacent regions for an extremely heavy precipitation event on July 21 2012. CMORPH and PEERSIANN-CSS misplaced the region of greatest rainfall accumulation, and failed to capture the spatial pattern of precipitation, evidenced by a low spatial correlation coefficient (CC). CMORPH overestimated the daily accumulated rainfall by 22.84% while PERSIANN-CCS underestimated by 72.75%. In the rainfall center, both CMORPH and PERSIANN-CCS failed to capture the temporal variation of the rainfall, and underestimated rainfall amounts by 43.43% and 87.26%, respectively. Based on our results, caution should be exercised when using CMORPH and PERSIANN-CCS as input for monitoring and forecasting floods in Beijing urban areas, and the potential for landslides in the mountainous zones west and north of Beijing. PMID:24691358

  10. Evaluation of high-resolution precipitation estimates from satellites during July 2012 Beijing flood event using dense rain gauge observations.

    PubMed

    Chen, Sheng; Liu, Huijuan; You, Yalei; Mullens, Esther; Hu, Junjun; Yuan, Ye; Huang, Mengyu; He, Li; Luo, Yongming; Zeng, Xingji; Tang, Guoqiang; Hong, Yang

    2014-01-01

    Satellite-based precipitation estimates products, CMORPH and PERSIANN-CCS, were evaluated with a dense rain gauge network over Beijing and adjacent regions for an extremely heavy precipitation event on July 21 2012. CMORPH and PEERSIANN-CSS misplaced the region of greatest rainfall accumulation, and failed to capture the spatial pattern of precipitation, evidenced by a low spatial correlation coefficient (CC). CMORPH overestimated the daily accumulated rainfall by 22.84% while PERSIANN-CCS underestimated by 72.75%. In the rainfall center, both CMORPH and PERSIANN-CCS failed to capture the temporal variation of the rainfall, and underestimated rainfall amounts by 43.43% and 87.26%, respectively. Based on our results, caution should be exercised when using CMORPH and PERSIANN-CCS as input for monitoring and forecasting floods in Beijing urban areas, and the potential for landslides in the mountainous zones west and north of Beijing. PMID:24691358

  11. Linking the environmental loads to the fate of PPCPs in Beijing: Considering both the treated and untreated wastewater sources.

    PubMed

    Wang, Bin; Dai, Guohua; Deng, Shubo; Huang, Jun; Wang, Yujue; Yu, Gang

    2015-07-01

    The environmental loads of pharmaceutical and personal care products (PPCPs) in Beijing were estimated from direct discharge of untreated wastewater and WWTP treated effluent. The annual environmental loads of 15 PPCP components ranged from 16.3 kg (propranolol) to 9.85 tons (caffeine). A fugacity model was developed to successfully estimate the PPCP pollution based on the estimated environmental load. The modeled results approximated the observed PPCP concentrations in Beijing. The untreated wastewater contributed significantly to PPCP pollution in Beijing, ranging from 46% (propranolol) to 99% (caffeine). The total environmental burden of target PPCPs ranged from 0.90 kg (propranolol) to 536 kg (caffeine). Water is the most important media for the fate of PPCPs. Monte Carlo-based concentration distributions of PPCPs are consistent with the observed results. The most important way to reduce the PPCP pollution is to both improve wastewater collection rate and adopt deep treatment technologies. PMID:25827690

  12. Characteristics of aerosol and meteorological parameters during major dust storm events (2005 - 2010) over Beijing, China

    NASA Astrophysics Data System (ADS)

    Zheng, Sheng; Cao, Chunxiang; Singh, Ramesh

    Multi satellite sensors are capable in monitoring dust storm, its path and changes in atmospheric parameters. The present paper discusses aerosol optical properties and meteorological parameters during major dust storm events (2005-2010) over Beijing, China. The back trajectory model shows that the dust is transported from the Inner Mongolia and Mongolia to Beijing. High aerosol optical depth (AOD) and low Ångström exponent (AE) values are observed during dusty days, the average AOD (675 nm) and AE (440-870 nm) during dusty days are 2.33 and 0.06, respectively. The aerosol size distribution (ASD) in coarse mode shows a large increase in the volume during dusty days. The single scattering albedo (SSA) increases with higher wavelength on dusty days, and higher compared to non-dusty days, indicating the presence of high scattering particles due to dust storm events. Characteristics of particles during dusty and non-dusty days are also supported by the real and imaginary parts of refractive index (RI). High air pollution index (API) during dusty days represent poor air quality is a serious health hazard at the time of dust events. The CO volume mixing ratio (COVMR) from Atmospheric Infrared Sounder (AIRS) shows decrease on the ground on dusty days, while the relative humidity (RH) and H _{2}0 mass mixing ratio (H _{2}OMMR) enhance. In addition, due to the dust storm in 2005, enhanced level of water vapor (WV) using Moderate Resolution Imaging Spectroradiometer (MODIS) data is observed in and around Beijing over the dust storms track.

  13. Numerical study of urbanization effect on a heavy storm event in Beijing

    NASA Astrophysics Data System (ADS)

    Liu, Z.

    2015-12-01

    In the past few decades, Great Beijing area has experienced rapid and widespread urbanization, which has substantially modified the land surface physical characteristics and affected urban regional weather and climate. A single layer urban canopy module has been developed based on the Community Land Surface Model Urban Module (CLMU) with several improvements: the energy balances on the five surface conditions (building roof, sun side and shaded side wall, pervious and impervious land surfaces) are considered separately. A method to calculate sky view factor is developed based on the physically process while most urban models simply provide an empirical value. This method improves the solar and long wave radiation simulation on each surface. The latent heat flux on both wall and impervious land is calculated; the anthropogenic heat is considered in terms of industrial production, domestic wastes, vehicles and air conditions. The urban effect on summer convective precipitation over Beijing was investigated by simulating a heavy storm event on July 21st 2012, when precipitation of averagely 164 mm was brought to Beijing within 6 hours, which is the heaviest during the past 60 years' record in the region. Numerical simulating experiment was set up by coupling Weather Research and Forecast (WRF)/SSiB3 model with the Modified CLMU (MCLMU). Several control cases without MCLMU were set up. The horizontal resolution in the inner domains was set to be 2 km. While all of the control results drastically underestimate the urban precipitation, the result of WRF/SSiB3/MCLMU is much closer to the observation. Sensitive experiments show that although large areas of impervious surfaces restrain the surface latent heat flux in urban, the anthropogenic heat and enhanced sensible heat flux warmed up the lower atmospheric layer then strengthen the vertical stratification instability, which is the key factor for heavy storm while moisture is sufficient.

  14. Respiratory infections associated with enterovirus D68 from 2011 to 2015 in Beijing, China.

    PubMed

    Zhang, Tiegang; Li, Aihua; Chen, Meng; Wu, Jiang; Huang, Fang

    2016-09-01

    Enterovirus D68 (EV-D68) is an emergent viral pathogen associated with mild to severe respiratory infections. In this study, we describe respiratory infections associated with EV-D68 in Beijing over a 4 year period. Total nucleic acid was extracted from 7,945 clinical specimens collected between January 5, 2011 and July 30, 2015 in Beijing and used for detecting EV-D68 and other enteroviruses by real-time PCR. Overall, 555/7,945 (6.99%) specimens were enterovirus positive: 12/7,945 (0.2%) specimens were EV-D68 positive. Of these patients, 11 were pediatric patients and 1 was a 76-year-old man. The main symptoms for the 12 EV-D68 positive patients were fever (10/12, 83.3%) and cough (6/12, 50%). Ten EV-D68 infection cases were identified in autumn or winter season. The phylogenetic relationships of the 12 EV-D68 viral strains with other strains were analyzed based on the sequences of viral protein 1(VP1). The EV-D68 strains from 2011 to 2013 belonged to groups 1 or 3, while all strains in 2014 were clustered into group 1 together with the strains circulating in the USA. In conclusion, EV-D68 played a role in respiratory infections in Beijing during this period. In addition, the most common EV-D68 strain detected was similar to that circulating in the USA in 2014. J. Med. Virol. 88:1529-1534, 2016. © 2016 Wiley Periodicals, Inc. PMID:26896830

  15. Concentrations and patterns of polychlorinated naphthalenes in urban air in Beijing, China.

    PubMed

    Xue, Lingnan; Zhang, Lifei; Yan, Yan; Dong, Liang; Huang, Yeru; Li, Xiaoxiu

    2016-11-01

    Air samples were collected, using a high-volume air sampler, at an urban site in Beijing from April 2014 to March 2015. The polychlorinated naphthalene (PCN) concentration in the atmosphere in each season was determined. The total PCN (total target tri- to octachloronaphthalene congeners) concentrations were 1.99-19.0 pg/m(3), and the mean was 7.20 pg/m(3). The PCN concentrations were higher in fall than summer, indicating that the concentrations varied significantly over time. The trichloronaphthalene homolog was the predominant PCN homolog in all four seasons. The PCN toxic equivalent (TEQ) concentrations were 0.42-6.89 fg/m(3), and the mean was 1.74 fg/m(3). The CN-66/67 and CN-73 congeners were the predominant contributors to the TEQ concentrations. The mean seasonal TEQ concentration decreased in the order fall (3.18 fg/m(3)) > winter (1.41 fg/m(3)) > summer (1.11 fg/m(3)) > spring (1.03 fg/m(3)). The TEQ concentrations and the PCN concentrations did not follow the same seasonal trends, but the highest TEQ and PCN concentrations were both found in fall. Correlation analysis, ratio analysis, and principal component analysis were used to investigate the sources of PCNs to the Beijing atmosphere. The results suggested that combustion processes may be the main sources of PCNs to the Beijing atmosphere. PMID:27497350

  16. Applying land use regression model to estimate spatial variation of PM₂.₅ in Beijing, China.

    PubMed

    Wu, Jiansheng; Li, Jiacheng; Peng, Jian; Li, Weifeng; Xu, Guang; Dong, Chengcheng

    2015-05-01

    Fine particulate matter (PM2.5) is the major air pollutant in Beijing, posing serious threats to human health. Land use regression (LUR) has been widely used in predicting spatiotemporal variation of ambient air-pollutant concentrations, though restricted to the European and North American context. We aimed to estimate spatiotemporal variations of PM2.5 by building separate LUR models in Beijing. Hourly routine PM2.5 measurements were collected at 35 sites from 4th March 2013 to 5th March 2014. Seventy-seven predictor variables were generated in GIS, including street network, land cover, population density, catering services distribution, bus stop density, intersection density, and others. Eight LUR models were developed on annual, seasonal, peak/non-peak, and incremental concentration subsets. The annual mean concentration across all sites is 90.7 μg/m(3) (SD = 13.7). PM2.5 shows more temporal variation than spatial variation, indicating the necessity of building different models to capture spatiotemporal trends. The adjusted R (2) of these models range between 0.43 and 0.65. Most LUR models are driven by significant predictors including major road length, vegetation, and water land use. Annual outdoor exposure in Beijing is as high as 96.5 μg/m(3). This is among the first LUR studies implemented in a seriously air-polluted Chinese context, which generally produce acceptable results and reliable spatial air-pollution maps. Apart from the models for winter and incremental concentration, LUR models are driven by similar variables, suggesting that the spatial variations of PM2.5 remain steady for most of the time. Temporal variations are explained by the intercepts, and spatial variations in the measurements determine the strength of variable coefficients in our models. PMID:25487555

  17. The consumption and recycling collection system of PET bottles: a case study of Beijing, China.

    PubMed

    Zhang, Hua; Wen, Zong-Guo

    2014-06-01

    After studying the recycling collection system of polyethylene terephthalate (PET) bottles worldwide, the authors conducted an intercept survey in Beijing. Two separate questionnaires were issued, one questionnaire to PET bottle consumers and one to PET bottle recyclers. In this study, consumers are defined as people that consume PET-bottled beverages in their daily life. Recyclers were defined as those involved in the collection and recycling of PET bottles. These include scavengers, itinerant waste buyers, small community waste-buying depots, medium/large redemption depots, and recycling companies. In total, 580 surveys were completed, including 461 by consumers and 119 by recyclers. The authors found that consumption of PET bottles in Beijing was nearly 100,000 tonnes in 2012. Age, occupation, gender, and education were identified as significant factors linked to PET-bottled beverage consumption, while income was not a significant factor. 90% Of post-consumed PET bottles were collected by informal collectors (i.e., scavengers and itinerant waste buyers). The survey also found that nearly all PET bottles were reprocessed by small factories that were not designed with pollution control equipment, which allows them to offer higher prices for waste recyclable bottles. As Beijing is trying to build a formal recycling collection system for recyclables, subsidies should be given to the formal recycling sector rather than being charged land use fees, and attention should also be given to informal recyclers that make their living from the collection of recyclables. Informal and formal sectors may work together by employing the scavengers and itinerant waste buyers for the formal sectors. In addition to the recycling of PET bottles, concern should also be allocated to reduce consumption, especially among young people, as they, compared to other groups, have a stronger demand for PET-bottled beverages and will be the main body of society. PMID:23948054

  18. Toward Beijing: linking HIV / AIDS to other women's issues is imperative.

    PubMed

    Forrest, K

    1995-01-01

    The senior advisor to the AIDSCAP Women's Initiative, Dr. E. Maxine Ankrah, is actively lobbying to secure the inclusion of HIV/AIDS language in the draft platform of the UN Fourth World Conference on Women: Action for Equality, Development and Peace scheduled for September 1995 in Beijing. She organized the only workshop on HIV/AIDS at the preparatory meeting in New York in March 1995. It examined the effects of poverty on the expanding epidemic among females. Workshop presentations included international perspectives on: the effect of structural adjustment programs on women's vulnerability; the relationship between poverty, female prostitution, and AIDS; credit schemes and education to empower rural women; reproductive rights; ethnic issues; and the need for women to help women. Obstacles that obscured the relationships between HIV/AIDS and other women's issues have been: that AIDS was initially defined as a medical problem; that risk groups were narrowly defined; and the emphasis on behavior that blames persons infected with HIV. Despite earlier obstacles, the draft platform has several sections with HIV/AIDS language. Strategic Objective C.3: Undertake Multi-Sectoral Initiatives Sensitive to Women's Life Situations addresses the HIV pandemic and other sexual and reproductive health issues. Some of the actions called for in this objective are involvement of women in decision making, expansion of peer education and outreach, and supporting research of woman-controlled prevention methods. AIDSCAP Women's Initiative and other nongovernmental organizations will work together focus attention on HIV/AIDS in Beijing. AIDSCAP plans to have resource publications available in Beijing as well as to host networking sessions. Unless it is waived, the policy prohibiting HIV-infected persons from entering China will preclude HIV-infected women from taking part in the Conference. PMID:12346008

  19. Numerical Study of Urbanization Effect on 2012 Heavy Storm Precipitation in Beijing

    NASA Astrophysics Data System (ADS)

    Liu, Z.; Liu, S.; Xue, Y.; Oleson, K. W.

    2014-12-01

    In the past few decades, Great Beijing area has experienced rapid and widespread urbanization, which has significantly modified the land surface physical characteristics and affects urban regional climate.A single layer urban canopy module has been developed based on the Community Land Surface Model Urban Module (CLMU) with improvements: the energy balances on the five surface conditions are considered separately: building roof, sun side and shaded side wall, pervious and impervious land surface. A method to calculate sky view factor is developed based on the physically process while most urban models simply provide an empirical value. This method improves the solar and long wave radiation simulation on each surface; a new scheme for calculating the latent heat flux is applied on both wall and impervious land; the anthropogenic heat is considered in terms of industrial production, domestic wastes, vehicles and air condition. The urban effect on summer convective precipitation under the unstable atmospheric condition over Beijing was investigated by simulating a heavy storm event in July 21st 2012. In this storm, precipitation of averagely 164 mm was brought to Beijing within 6 hours, which is the record of past 60 years in the region. Numerical simulating experiment was set up by coupling Weather Research and Forecast (WRF)/SSiB3 model with the Modified CLMU (MCLMU). Several control cases without MCLMU were set up. The horizontal resolution in the inner domains was set to be 2 km. While all of the control results drastically underestimate the urban precipitation, the result of WRF/SSiB3/MCLMU is much closer to the observation. Sensitive experiments show that the existence of large area of impervious surfaces restrain the surface evaporation and latent heat flux in urban while the anthropogenic heat and enhanced sensible heat flux warm up the lower atmospheric layer and strengthen the vertical stratification instability, which is the key factor for storm while

  20. Analysis of Spatial Variations and Sources of Heavy Metals in Farmland Soils of Beijing Suburbs

    PubMed Central

    Zou, Jianmei; Dai, Wei; Gong, Shengxuan; Ma, Zeyu

    2015-01-01

    To understand the effect of intense human activities in suburbs on environmental quality, we obtained 758 measurements of the heavy metals in certain farmland soils of the Beijing suburbs. Multivariate statistical analysis and geostatistical analysis were used to conduct a basic analysis of the heavy metal concentrations, the distribution characteristics and the sources of pollution of the farmland soils in these suburbs. The results showed the presence of eight heavy metals in the agricultural soils at levels exceeding the background values for As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn. In particular, all the measured Cr concentrations exceeded the background value, while As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn were present at 1.13, 1.68, 1.95, 1.43, 1.63, 0.79, 0.92 and 1.36 times their background values, respectively. The results of correlation, factor and spatial structure analyses showed that Cd, Cu, Pb and Zn were strongly homologous, whereas Cr and Hg showed a degree of heterogeneity. The analysis further indicated that in addition to natural factors, Cd, Cu, Pb and Zn in the soil were mainly associated with distribution from road traffic and land use status. Different agricultural production measures in the various areas were also important factors that affected the spatial distribution of the soil Cr concentration. The major sources of Hg pollution were landfills for industrial waste and urban domestic garbage, while the spatial distribution of As was more likely to be a result of composite pollution. The regional distribution of the heavy metals indicated that except for Cr and Hg, the high heavy metal levels occurred in districts and counties with higher organic matter concentrations, such as the northwestern and southeastern suburbs of Beijing. There was no significant Ni pollution in the agricultural soils of the Beijing suburbs. PMID:25658749

  1. The composition, trend and impact of urban solid waste in Beijing.

    PubMed

    Xiao, Yi; Bai, Xuemei; Ouyang, Zhiyun; Zheng, Hua; Xing, Fangfang

    2007-12-01

    This paper provides an overview of the trend of generation, composition, and management of municipal solid waste, and estimates the carbon emissions arising from municipal solid waste management in Beijing. The correlation analysis conducted shows that the generation of municipal solid waste in Beijing has been growing steadily, showing high correlations (r > 0.9) to the total GDP, per capita income, and the population. Food waste showed an increasing trend since 1990. Compared with the results of an investigation in 1990, ash and woodchips content in 2003 declined from 56% to 17%, while the percentage of paper and plastic increased from 10% to 29% over the same period. The calorific value of the municipal waste also increased, from 2,686 kJ/kg in 1990 to 4,667 kJ/kg in 2003, indicating that the waste is suitable for incineration. Currently, the source separation ratio of municipal waste is approximately 15%. About 94% of all the collected solid waste goes to the landfill while 4% is composted and 2% is incinerated. A moderate garbage collection fee is applied to both permanent and temporary residents in Beijing, but the willingness to pay for solid waste collection and treatment is still low. Under current treatment mode, the total amounts of carbon emission from waste disposal sites and incineration increased with the increase of municipal solid waste, from 29.8 Gg in 1990 to 84.5 Gg in 2003, including 83.3 Gg of CH(4) and 22.0 Gg of CO(2). The data availability and methodological challenges in monitoring the quantity and characteristics of municipal solid waste are discussed. PMID:17503212

  2. "Looking at the world through women's eyes": Latin Americans at Beijing.

    PubMed

    Farmelo, M

    1996-01-01

    This news article discusses the perspective brought by Latin American women to the women's conference held in Beijing in 1995. One major accomplishment was the inclusion of Caribbean women into the regional Latin American exhibition space and the regional gatherings. The Latin American conference space was used to present regional exhibits, music and dance performances, theater productions, and messages from country delegates. The official government conference included the well-organized advocacy efforts among Latin American delegates. This accomplishment reflected the improvement in skills among delegates since the Mar del Plata meetings. The nongovernmental organization (NGO) conference had some serious transportation difficulties due to its location in Huairou, 35 miles north of Beijing. The distance exhausted participants and reduced the NGO forum impact on the official conference. Participants at the NGO conference also were restricted in their freedom of movement by the Chinese Organizing Committee. There was insufficient infrastructure for handling planned plenary sessions, lack of access for the disabled, harassment of certain special interest groups, and obstruction of meetings in hotels. Secret searches were conducted by Chinese officials in delegates' hotel rooms. Non-English speakers were able to participate only in large plenary sessions and selected workshops. Non-Spanish speaking Latin Americans walked out of Latin American events held in Spanish. Women were also frustrated that views strongly articulated on the plenary floor were excluded from the Plan of Action and from press coverage. To be successful, plans for the post-Beijing period must account for the diversity of women's groups. PMID:12291720

  3. Epidemiology of Chlamydia psittaci Infection in Racing Pigeons and Pigeon Fanciers in Beijing, China.

    PubMed

    Ling, Y; Chen, H; Chen, X; Yang, X; Yang, J; Bavoil, P M; He, C

    2015-08-01

    Over 3 million racing pigeons (Columba livia) are registered in Beijing City Center for gambling purposes. During 2008-2010, we evaluated the occurrence and prevalence of Chlamydia psittaci in racing pigeons as well as the possible zoonotic transmission to pigeon fanciers in six districts of Beijing where pigeon races are particularly popular. C. psittaci-specific serum antibody titres were obtained from 370 pigeons and 79 fanciers using enzyme-linked immunosorbent assay. In addition, 206 and 67 throat swabs were, respectively, collected from pigeons and fanciers and tested for the presence of chlamydial antigen using immunofluorescence. C. psittaci-specific serum antibody was detected in 37 of 370 pigeons and 19 of 79 fanciers. Of 206 pigeon clinical specimens, 55 were positive for C. psittaci antigen, while 16 of 67 swabs from the pigeon fanciers were positive. Based on ompA sequence analysis, the genotype of several avian and human isolates was genotype B. Thus, both high-titre C. psittaci-specific antibody and C. psittaci-specific antigen were found with relatively high frequency in the pigeon flocks as well as in the pigeon fanciers. Our study suggests that C. psittaci infection is prevalent among the racing pigeon population in Beijing. Moreover, detection of serum antibodies and antigen in pigeon fanciers suggests that exposure and possible zoonotic transmission of C. psittaci from racing pigeons to humans does occur. In view of the life-threatening respiratory illness C. psittaci may cause in humans, regulatory public health measures, to prevent further spread of the pathogen in avian populations and possible transmission to exposed humans, are urgently needed. PMID:25244602

  4. Modeled deposition of fine particles in human airway in Beijing, China

    NASA Astrophysics Data System (ADS)

    Li, Xiaoying; Yan, Caiqing; Patterson, Regan F.; Zhu, Yujiao; Yao, Xiaohong; Zhu, Yifang; Ma, Shexia; Qiu, Xinghua; Zhu, Tong; Zheng, Mei

    2016-01-01

    This study aims to simulate depositions of size-segregated particles in human airway in Beijing, China during seasons when fine particulate matter concentrations are high (December 2011 and April 2012). Particle size distributions (5.6-560 nm, electrical mobility diameter) near a major road in Beijing were measured by the TSI Fast Mobility Particle Sizer (FMPS). The information of size distributions provided by FMPS was applied in the Multiple-Path Particle Dosimetry model (MPPD) to quantify number and mass depositions of particles in human airway including extrathoracic (ET), tracheobronchial (TB), and pulmonary (PUL) regions of exposed Chinese in Beijing. Our results show that under ambient conditions, particle number concentration (NC) deposition in PUL is the highest in the three major regions of human airway. The total particle NC deposition in human airway in winter is higher than that in spring, especially for ultrafine particles (1.8 times higher) while particle mass concentration (MC) deposition is higher in spring. Although particle MC in clean days are much lower than that in heavily polluted days, total particle NC deposition in human airway in clean days is comparable to that in heavily polluted days. NC deposition for nucleation mode particles (10-20 nm, aerodynamic diameter) in clean days is higher than that in heavily polluted days. MC deposition for accumulation mode particles (100-641 nm, aerodynamic diameter) in heavily polluted days is much higher than that in clean days, while that of nucleation mode is negligible. The temporal variation shows that the arithmetic mean and the median values of particle NC and MC depositions in the evening are both the highest, followed by morning and noon, and it is most likely due to increased contribution from traffic emissions.

  5. Scenario analysis to vehicular emission reduction in Beijing-Tianjin-Hebei (BTH) region, China.

    PubMed

    Guo, Xiurui; Fu, Liwei; Ji, Muse; Lang, Jianlei; Chen, Dongsheng; Cheng, Shuiyuan

    2016-09-01

    Motor vehicle emissions are increasingly becoming one of the important factors affecting the urban air quality in China. It is necessary and useful to policy makers to demonstrate the situation given the relevant pollutants reduction measures are taken. This paper predicted the reduction potentials of conventional pollutants (PM10, NOx, CO, HC) under different control strategies and policies in the Beijing-Tianjin-Hebei (BTH) region during 2011-2020. There are the baseline and 5 control scenarios designed, which presented the different current and future possible vehicular emissions control measures. Future population of different kinds of vehicles were predicted based on the Gompertz model, and vehicle kilometers travelled estimated as well. After that, the emissions reduction under the different scenarios during 2011-2020 could be estimated using emission factors and activity level data. The results showed that, the vehicle population in the BTH region would continue to grow up, especially in Tianjin and Hebei. Comparing the different scenarios, emission standards updating scenario would achieve a substantial reduction and keep rising up for all the pollutants, and the scenario of eliminating high-emission vehicles can reduce emissions more effectively in short-term than in long-term, especially in Beijing. Due to the constraints of existing economical and technical level, the reduction effect of promoting new energy vehicles would not be significant, especially given the consideration of their lifetime impact. The reduction effect of population regulation scenario in Beijing cannot be ignorable and would keep going up for PM10, CO and HC, excluding NOx. Under the integrated scenario considering all the control measures it would achieve the maximum reduction potential of emissions, which means to reduce emissions of PM10, NOx, CO, HC, by 56%, 59%, 48%, 52%, respectively, compared to BAU scenario for the whole BTH region in 2020. PMID:27325548

  6. Distribution and sources of oxygenated non-hydrocarbons in topsoil of Beijing, China.

    PubMed

    Zhang, Zhihuan; Wan, Tiantian; Peng, Xuyang; He, Guangxiu; Liu, Yu; Zeng, Li

    2016-08-01

    The oxygenated non-hydrocarbon compounds are widely distributed in soil. To investigate the distribution and origin of these compounds in topsoil of Beijing, their contents and compositions were measured in topsoil from 62 sites in Beijing. The research results showed that oxygenated non-hydrocarbons were composed primarily of C6∼C28 n-fatty acids, C12∼C28 n-fatty alcohols, n-fatty acid methyl esters, phthalates, sterols, and dehydroabietic acid in the topsoil of Beijing. The contents and compositions of these compounds varied with the sampling site. The concentrations of n-fatty acids and phthalate esters were the highest at all sites, followed by sterols, n-fatty acid methyl esters, fatty alcohols, and dehydroabietic acid in order. The n-fatty acids had a main peak of C16, followed by C18. An odd or even carbon number predominance was not observed in the low-molecular-weight n-fatty acids, indicating a fossil fuel or organic matter source. However, some high-molecular-weight n-fatty acids with an even carbon predominance may derive from a biomass. The n-fatty alcohols showed a main peak of C22 and were predominated by an even carbon number, suggesting plant, microbial, or other natural origins. Phthalates, including diethyl phthalate (DEP), diisobutyl phthalate (DIBP), dibutyl phthalate (DBP), diethylhexyl phthalate (DEHP), and dimethylphthalate (DMP), were detected. The content of phthalate esters was higher in the samples collected from dense human activity areas. The concentrations of DBP, DEHP, and DIBP were relatively high, indicating an anthropogenic source. The sterols (predominantly β-sitosterol) originated from biological sources, especially plants. The n-fatty acid methyl esters and dehydroabietic acid in topsoil showed apparent even carbon predominance with the former mainly derived from microorganisms or plants and the latter from cork combustion products. PMID:27172982

  7. Size-resolved particulate matter composition in Beijing during pollution and dust events

    NASA Astrophysics Data System (ADS)

    Dillner, Ann M.; Schauer, James J.; Zhang, Yuanhang; Zeng, Limin; Cass, Glen R.

    2006-03-01

    Each spring, Beijing, China, experiences dust storms which cause high particulate matter concentrations. Beijing also has many anthropogenic sources of particulate matter including the large Capitol Steel Company. On the basis of measured size segregated, speciated particulate matter concentrations, and calculated back trajectories, three types of pollution events occurred in Beijing from 22 March to 1 April 2001: dust storms, urban pollution events, and an industrial pollution event. For each event type, the source of each measured element is determined to be soil or anthropogenic and profiles are created that characterize the particulate matter composition. Dust storms are associated with winds traveling from desert regions and high total suspended particle (TSP) and PM2.5 concentrations. Sixty-two percent of TSP is due to elements with oxides and 98% of that is from soil. Urban pollution events have smaller particulate concentrations but 49% of the TSP is from soil, indicating that dust is a major component of the particulate matter even when there is not an active dust storm. The industrial pollution event is characterized by winds from the southwest, the location of the Capitol Steel Company, and high particulate concentrations. PM2.5 mass and acidic ion concentrations are highest during the industrial pollution event as are Mn, Zn, As, Rb, Cd, Cs and Pb concentrations. These elements can be used as tracers for industrial pollution from the steel mill complex. The industrial pollution is potentially more detrimental to human health than dust storms due to higher PM2.5 concentrations and higher acidic ion and toxic particulate matter concentrations.

  8. Characteristics of carbonaceous aerosol in the region of Beijing, Tianjin, and Hebei, China

    NASA Astrophysics Data System (ADS)

    Zhao, Pusheng; Dong, Fan; Yang, Yadong; He, Di; Zhao, Xiujuan; Zhang, Wenzong; Yao, Qing; Liu, Huaiyu

    2013-06-01

    More than 400 PM2.5 samples were collected at four urban sites in Beijing (BJ), Tianjin (TJ), Shijiazhuang (SJZ), and Chengde (CD), and also one site in Shangdianzi (SDZ), which was used as a regional background station, over four seasons from 2009 to 2010. The organic carbon (OC) and elemental carbon (EC) in each sample were analyzed. The average annual concentrations were 71.8-191.2 μg m-3 for PM2.5, 10.8-26.4 μg m-3 for OC, and 3.9-9.7 μg m-3 for EC at the five sites. OC and EC concentrations were lower in the spring and summer and much higher in the autumn and winter, mainly due to aerosol emissions from additional fuel combustion for heating. OC/EC ratios were lowest in the summer and highest in the winter at SDZ, BJ, TJ, and SJZ. These seasonal trends indicate that the characteristics of carbonaceous aerosol pollution were spatially similar and season-dependent in the plain area of Beijing, Tianjin, and Hebei (BTH). An EC tracer method was used to calculate the concentrations for secondary organic carbon (SOC); SOC concentrations were also higher in the autumn and winter and lowest during the summer at all five sites. A stable atmosphere and low temperatures, which were more frequent during the winter and autumn, facilitated the accumulation of air pollutants and accelerated the condensation or adsorption of volatile organic compounds in the BTH area. Over the past ten years (1999-2009), Beijing had observed a decrease in the EC concentrations during every season and a remarkable reduction in aerosol emissions from coal combustion for heating.

  9. Progress of research on plasma facing materials in University of Science and Technology Beijing

    NASA Astrophysics Data System (ADS)

    Ge, Chang-Chun; Zhou, Zhang-Jian; Song, Shu-Xiang; Du, Juan; Zhong, Zhi-Hong

    2007-06-01

    In this paper, we report some new progress on plasma facing materials in University of Science and Technology Beijing (USTB), China. They include fabrication of tungsten coating with ultra-fine grain size by atmosphere plasma spraying; fabrication of tungsten with ultra-fine grain size by a newly developed method named as resistance sintering under ultra-high pressure; using the concept of functionally graded materials to join tungsten to copper based heat sink; joining silicon doped carbon to copper by brazing using a Ti based amorphous filler and direct casting.

  10. New attempts on increasing economic gains in the development of geothermal resources in Beijing, China

    SciTech Connect

    Zheng, K.

    1997-12-31

    The development of geothermal resources in the city of Beijing and its surrounding suburbs has been made possible by investments from companies in the surrounding Provinces of China. The development of these geothermal deposits has created a market for hot spring real estate. The real estate has been developed into comprehensive projects for recreation and vacation resorts, in addition to, heath care centers and greenhouse farming. This new attempt to develop these geothermal resources has increased the economic growth of the area and interest in geothermal expansion.

  11. Simulation of an rf gun injector for the Beijing free electron laser

    NASA Astrophysics Data System (ADS)

    Liu, Hongxiu

    1990-09-01

    An rf gun injector is being developed in the Institute of High Energy Physics, Academia Sinica. It will be used for a 30 MeV, 2856 MHz disk-loaded travelling-wave linac to drive the Beijing free electron laser (BFEL). It consists of an rf thermionic gun with a LaB 6 cathode and an achromatic but nonisochronic alpha magnet serving as the momentum filter. The transverse and longitudinal dynamics of a single electron bunch were simulated using SUPERFISH and PARMELA. The injector performance was examined in the light of the simulation results.

  12. Impact of fine particulate fluctuation and other variables on Beijing's air quality index.

    PubMed

    Chen, Bo; Lu, Shaowei; Li, Shaoning; Wang, Bing

    2015-04-01

    We analyzed fluctuation in Beijing's air quality over 328 days, based on air quality grades and air quality data from 35 atmospheric monitoring stations. Our results show the air over Beijing is subject to pollution 152 days of the year, or 46.34%. Among all pollutants, fine particulates, solid or liquid, 2.5 μm or less in size (PM2.5), appeared most frequently as the primary pollutant: 249 days, or 76% of the sample year (328 days). Nitrogen dioxide (NO2) and coarse particulates (PM10) cause the least pollution, appearing only 7 and 3 days, or 2 and 1% of the sample year, respectively. In Beijing, fine particulates like PM2.5 vary seasonally: 154.54 ± 18.60 in winter > 145.22 ± 18.61 in spring > 140.16 ± 20.76 in autumn > 122.37 ± 13.42 in summer. Air quality is best in August and worst in December, while various districts in Beijing experience different air quality. To be specific, from south to north and from west to east, air quality tends to improve. Meteorological elements have a constraining effect on air pollutants, which means there is a linear correlation between the air quality index and humidity, rainfall, wind speed, and temperature. Under a typical pollution scenario, the higher the air quality index (AQI) value, the lower the wind speed and the greater the relative humidity; the lower the AQI value, the higher the wind speed and lower the relative humidity. Analysis of influencing factors reveals that the air pollution is mainly particulate matter produced by burning coal, vehicle emissions, volatile oils and gas, fast development of food services, emissions from the surrounding region, and natural dust clouds formed in arid areas to the northwest. Topography affects the distribution of meteorological conditions, in turn varying air quality over the region from one location to another. Human activities also exercise impact on urban air quality with dual functions. PMID:25563832

  13. Online beam energy measurement of Beijing electron positron collider II linear accelerator.

    PubMed

    Wang, S; Iqbal, M; Liu, R; Chi, Y

    2016-02-01

    This paper describes online beam energy measurement of Beijing Electron Positron Collider upgraded version II linear accelerator (linac) adequately. It presents the calculation formula, gives the error analysis in detail, discusses the realization in practice, and makes some verification. The method mentioned here measures the beam energy by acquiring the horizontal beam position with three beam position monitors (BPMs), which eliminates the effect of orbit fluctuation, and is much better than the one using the single BPM. The error analysis indicates that this online measurement has further potential usage such as a part of beam energy feedback system. The reliability of this method is also discussed and demonstrated in this paper. PMID:26931839

  14. Air quality during the 2008 Beijing Olympics: secondary pollutants and regional impact

    NASA Astrophysics Data System (ADS)

    Wang, T.; Nie, W.; Gao, J.; Xue, L. K.; Gao, X. M.; Wang, X. F.; Qiu, J.; Poon, C. N.; Meinardi, S.; Blake, D.; Ding, A. J.; Chai, F. H.; Zhang, Q. Z.; Wang, W. X.

    2010-05-01

    This paper presents the first results of the atmospheric measurements of trace gases and aerosols at three surface sites in and around Beijing before and during the 2008 Olympics. We focus on secondary pollutants including ozone, fine sulfate and nitrate, and the contribution of regional sources in summer 2008. The results reveal different responses of secondary pollutants to the control measures from primary pollutants. Ambient concentrations of vehicle-related nitrogen oxides (NOx) and volatile organic compounds (VOCs) at an urban site dropped by 25% and 20-45% in the first two weeks after full control was put in place, but the levels of ozone, sulfate and nitrate in PM2.5 increased by 16%, 64%, 37%, respectively, compared to the period prior to the full control; wind data and back trajectories indicated the contribution of regional pollution from the North China Plain. Air quality (for both primary and secondary pollutants) improved significantly during the Games, which were also associated with the changes in weather conditions (prolonged rainfall, decreased temperature, and more frequent air masses from clean regions). A comparison of the ozone data at three sites on eight ozone-pollution days, when the air masses were from the southeast-south-southwest sector, showed that regional pollution sources contributed 34%-88% to the peak ozone concentrations in urban Beijing. Ozone production efficiencies at two sites were low (~3 ppbv/ppbv), indicating that ozone formation was being controlled by VOCs. Compared with data collected in 2005 at a downwind site, the concentrations of ozone, sulfur dioxide (SO2), total sulfur (SO2+PM2.5 sulfate), carbon monoxide (CO), reactive aromatics (toluene and xylenes) sharply decreased (by 8-64%) in 2008, but no significant changes were observed for the concentrations of PM2.5, fine sulfate, total odd reactive nitrogen (NOy), and longer lived alkanes and benzene. We suggest that these results indicate the success of the government

  15. Modern Tectonic Deformation in the Active Basin-and-Range Province Northwest of Beijing, China

    NASA Astrophysics Data System (ADS)

    Mi, Suting; Wen, Xueze

    2013-04-01

    Our study region is the northwest of Beijing, northern north China. The most typical extensional active tectonic area of the China continent, called the active basin-and-range province northwest of Beijing, exist there. This active tectonic province is made up of several NE-trending Quaternary graben basins and horst ranges between basins. An about 1500-year-long written historical record has suggested that there have been no major earthquakes with magnitude 7 or greater occurred in most of the study region since AD 512. So, the characteristic of modern tectonic deformation of the study region and its implication for the future seismic potential of major earthquakes are important scientific issues. In this study, based on data of regional GPS station velocities and active tectonics, combining relocated earthquake distribution, we make a preliminary analysis on the characteristic of the modern tectonic deformation of the study region. We design three zones across deferent segments of the active basin-and-range province to analyze both the present tectonic deformation from the GPS velocity profiles and the major fault's downward-extents from the relocated hypocenters. Our analyses reveal that: (1) Significant NNW-ward and SSE-ward horizontal extension exists on different segments of the active basin-and-range province northwest of Beijing at rates of 2 to 3mm /yr, accompanied with right-lateral shear deformation at 1 to 2mm/yr. (2) On the western and middle segments of the active basin and range province, most of the total horizontal extension and shear deformation happen in the width from the Huangqihai basin to the Datong-Yanggao basin , suggesting that some major faults in this width could have had relatively-high strain build-up. (3) It is possible that one or more basement detachment belts exist under the active basins, and it or they possibly dip(s) southeastern-ward. (4) The modern tectonic extensional rate is up to 2 to 3mm /yr in the study region. However

  16. Source Apportionment of PM2.5 in Beijing, China Using Organic Tracers

    NASA Astrophysics Data System (ADS)

    Zheng, M.; Cass, G. R.; Salmon, L. G.; Schauer, J. J.

    2001-12-01

    In 2000, the annual average concentration of PM2.5 measured at five air quality monitoring sites in Beijing, China was found to be 101 micrograms per cubic meter, which is significantly higher than the annual average fine particle concentrations in many North American and European urban locations. Such high concentrations of airborne fine particulate matter lead to a variety of air quality problems including severe visibility reduction. Development of an effective strategy for reducing the air pollution emissions in Beijing requires a clear understanding of the composition, concentration, and sources of these fine particles in the atmosphere. Daily average PM2.5 samples were collected simultaneously once every 6th day at five air quality monitoring stations in Beijing, China during January, April, July, and October 2000. The samples obtained each month at each site were combined as a monthly composite sample for detailed organic tracer analysis by GC/MS (gas chromatography/mass spectrometry). The concentrations of one hundred organic compounds were quantified in each composite sample, including n-alkanes, branched alkanes, cycloalkanes, n-alkanoic acids, n-alkenoic acids, PAHs (polycyclic aromatic hydrocarbons), oxy-PAHs, hopanes, steranes, alkanedioic acids, resin acids, aromatic acids as well as key molecular marker compounds. The identified organic tracers along with elemental carbon, organic carbon, Al and Si which have been previously quantified were applied in a chemical mass balance model to apportion the sources contributing to PM2.5 mass. The major sources include coal combustion, wood burning, gasoline-power vehicle exhaust, diesel exhaust, crustal material, meat cooking, vegetative detritus, as well as secondary aerosol formation. Significant seasonal variations in the source contributions to PM2.5 were observed, e.g., higher contribution from crustal material in April and higher concentration from coal combustion in January. The highest concentration of

  17. Earthquake Strong Ground Motion Scenario at the 2008 Olympic Games Sites, Beijing, China

    NASA Astrophysics Data System (ADS)

    Liu, L.; Rohrbach, E. A.; Chen, Q.; Chen, Y.

    2006-12-01

    Historic earthquake record indicates mediate to strong earthquakes have been frequently hit greater Beijing metropolitan area where is going to host the 2008 summer Olympic Games. For the readiness preparation of emergency response to the earthquake shaking for a mega event in a mega city like Beijing in summer 2008, this paper tries to construct the strong ground motion scenario at a number of gymnasium sites for the 2008 Olympic Games. During the last 500 years (the Ming and Qing Dynasties) in which the historic earthquake record are thorough and complete, there are at least 12 earthquake events with the maximum intensity of VI or greater occurred within 100 km radius centered at the Tiananmen Square, the center of Beijing City. Numerical simulation of the seismic wave propagation and surface strong ground motion is carried out by the pseudospectral time domain methods with viscoelastic material properties. To improve the modeling efficiency and accuracy, a multi-scale approach is adapted: the seismic wave propagation originated from an earthquake rupture source is first simulated by a model with larger physical domain with coarser grids. Then the wavefield at a given plane is taken as the source input for the small-scale, fine grid model for the strong ground motion study at the sites. The earthquake source rupture scenario is based on two particular historic earthquake events: One is the Great 1679 Sanhe-Pinggu Earthquake (M~8, Maximum Intensity XI at the epicenter and Intensity VIII in city center)) whose epicenter is about 60 km ENE of the city center. The other one is the 1730 Haidian Earthquake (M~6, Maximum Intensity IX at the epicenter and Intensity VIII in city center) with the epicentral distance less than 20 km away from the city center in the NW Haidian District. The exist of the thick Tertiary-Quaternary sediments (maximum thickness ~ 2 km) in Beijing area plays a critical role on estimating the surface ground motion at the Olympic Games sites, which

  18. Quantitative evaluation of emission controls on primary and secondary organic aerosol sources during Beijing 2008 Olympics

    NASA Astrophysics Data System (ADS)

    Guo, S.; Hu, M.; Guo, Q.; Zhang, X.; Schauer, J. J.; Zhang, R.

    2013-08-01

    To assess the primary and secondary sources of fine organic aerosols after the aggressive implementation of air pollution controls during the 2008 Beijing Olympic Games, 12 h PM2.5 values were measured at an urban site at Peking University (PKU) and an upwind rural site at Yufa during the CAREBEIJING-2008 (Campaigns of Air quality REsearch in BEIJING and surrounding region) summer field campaign. The average PM2.5 concentrations were 72.5 ± 43.6 μg m-3 and 64.3 ± 36.2 μg m-3 (average ± standard deviation, below as the same) at PKU and Yufa, respectively, showing the lowest concentrations in recent years. Combining the results from a CMB (chemical mass balance) model and secondary organic aerosol (SOA) tracer-yield model, five primary and four secondary fine organic aerosol sources were compared with the results from previous studies in Beijing. The relative contribution of mobile sources to PM2.5 concentrations was increased in 2008, with diesel engines contributing 16.2 ± 5.9% and 14.5 ± 4.1% and gasoline vehicles contributing 10.3 ± 8.7% and 7.9 ± 6.2% to organic carbon (OC) at PKU and Yufa, respectively. Due to the implementation of emission controls, the absolute OC concentrations from primary sources were reduced during the Olympics, and the contributions from secondary formation of OC represented a larger relative source of fine organic aerosols. Compared with the non-controlled period prior to the Olympics, primary vehicle contributions were reduced by 30% at the urban site and 24% at the rural site. The reductions in coal combustion contributions were 57% at PKU and 7% at Yufa. Our results demonstrate that the emission control measures implemented in 2008 significantly alleviated the primary organic particle pollution in and around Beijing. However, additional studies are needed to provide a more comprehensive assessment of the emission control effectiveness on SOA formation.

  19. Urban stress-induced biogenic VOC emissions impact secondary aerosol formation in Beijing

    NASA Astrophysics Data System (ADS)

    Ghirardo, A.; Xie, J.; Zheng, X.; Wang, Y.; Grote, R.; Block, K.; Wildt, J.; Mentel, T.; Kiendler-Scharr, A.; Hallquist, M.; Butterbach-Bahl, K.; Schnitzler, J.-P.

    2015-08-01

    Trees can significantly impact the urban air chemistry by the uptake and emission of reactive biogenic volatile organic compounds (BVOCs), which are involved in ozone and particle formation. Here we present the emission potentials of "constitutive" (cBVOCs) and "stress-induced" BVOCs (sBVOCs) from the dominant broadleaf woody plant species in the megacity of Beijing. Based on an inventory of BVOC emissions and the tree census, we assessed the potential impact of BVOCs on secondary particulate matter formation in 2005 and 2010, i.e., before and after realizing the large tree-planting program for the 2008 Olympic Games. We found that sBVOCs, such as fatty acid derivatives, benzenoids and sesquiterpenes, constituted a significant fraction (∼ 15 %) of the total annual BVOC emissions, and we estimated that the overall annual BVOC budget may have doubled from ∼ 3.6 × 109 g C year-1 in 2005 to ∼ 7.1 × 109 g C year-1 in 2010 due to the increase in urban greens, while at the same time, the emission of anthropogenic VOCs (AVOCs) could be lowered by 24 %. Based on our BVOC emission assessment, we estimated the biological impact on SOA mass formation in Beijing. Compared to AVOCs, the contribution of biogenic precursors (2-5 %) for secondary particulate matter in Beijing was low. However, sBVOCs can significantly contribute (∼ 40 %) to the formation of total secondary organic aerosol (SOA) from biogenic sources; apparently, their annual emission increased from 1.05 μg m-3 in 2005 to 2.05 μg m-3 in 2010. This study demonstrates that biogenic and, in particular, sBVOC emissions contribute to SOA formation in megacities. However, the main problems regarding air quality in Beijing still originate from anthropogenic activities. Nevertheless, the present survey suggests that in urban plantation programs, the selection of plant species with low cBVOC and sBVOC emission potentials have some possible beneficial effects on urban air quality.

  20. Hand, foot and mouth disease caused by coxsackievirus A6, Beijing, 2013.

    PubMed

    Hongyan, Gu; Chengjie, Ma; Qiaozhi, Yang; Wenhao, Hua; Juan, Li; Lin, Pang; Yanli, Xu; Hongshan, Wei; Xingwang, Li

    2014-12-01

    Specimens and clinical data were collected from 243 hand, foot and mouth disease patients in Beijing in 2013. In total, 130 stool specimens were genotyped for enterovirus. Hand, foot and mouth disease was mainly detected in suburban areas and at the edges of urban areas between May and August. Coxsackievirus (CV) A6 replaced enterovirus (EV) 71 and CVA16, becoming the main causative agent of hand, foot and mouth disease. CVA6 infection led to significantly reduced fever duration and glucose levels compared with EV71 infection. PMID:25037037

  1. Online beam energy measurement of Beijing electron positron collider II linear accelerator

    NASA Astrophysics Data System (ADS)

    Wang, S.; Iqbal, M.; Liu, R.; Chi, Y.

    2016-02-01

    This paper describes online beam energy measurement of Beijing Electron Positron Collider upgraded version II linear accelerator (linac) adequately. It presents the calculation formula, gives the error analysis in detail, discusses the realization in practice, and makes some verification. The method mentioned here measures the beam energy by acquiring the horizontal beam position with three beam position monitors (BPMs), which eliminates the effect of orbit fluctuation, and is much better than the one using the single BPM. The error analysis indicates that this online measurement has further potential usage such as a part of beam energy feedback system. The reliability of this method is also discussed and demonstrated in this paper.

  2. Tuberculosis Beijing strain outbreak in an Israeli Arab rural community linked to an incarcerated immigrant.

    PubMed

    Bishara, H; Rorman, E; Mor, Z; Shechter-Amram, D; Weiler-Ravell, D

    2014-12-01

    A tuberculosis (TB) outbreak with six definite and four probable cases, caused by a Beijing strain isolate, occurred in an Arab rural community in north Israel. Using epidemiological investigation and strain genotyping, we identified the source case as an incarcerated immigrant. This outbreak illustrates how a systematic breakdown in TB prevention and control measures at multiple levels, within prisons and upon exiting prison, can result in rapid, cross-ethnic transmission of TB to a low-risk population. The close social bonds in this rural community and downsizing of the regional TB clinic staff may also have contributed to the magnitude of this outbreak. PMID:25517819

  3. Characteristics of atmospheric organic and elemental carbon aerosols in urban Beijing, China

    NASA Astrophysics Data System (ADS)

    Ji, Dongsheng; Zhang, Junke; He, Jun; Wang, Xiaoju; Pang, Bo; Liu, Zirui; Wang, Lili; Wang, Yuesi

    2016-01-01

    Organic carbon (OC) and elemental carbon (EC) in PM2.5 were measured hourly with a semicontinuous thermal-optical analyzer in urban Beijing, China, from Mar 1, 2013 to Feb 28, 2014. The annual mean concentrations of OC and EC in Beijing were 14.0 ± 11.7 and 4.1 ± 3.2 μg/m3, respectively. The concentrations observed in this study were lower than those of other reports over the past ten years; however, the concentrations were higher than those reported from most of the megacities in North America and Europe. These findings suggest that OC and EC remained at high levels despite the implementation of strict control measures to improve air quality. The OC and EC concentrations exhibited strong seasonality, with high values in the autumn and winter but low values in the spring and summer in Beijing. The diurnal OC and EC cycles were characterized by higher values at night and in the morning because of primary emissions, accumulations and low boundary-layer heights. Due to increasing photochemical activity, a well-defined OC peak was observed at approximately noon. The OC and EC concentrations followed typical lognormal patterns in which more than 75% of the OC samples had concentrations between 0.9 and 18.0 μg/m3 and 75% of the EC samples had concentrations between 0.4 and 5.6 μg/m3. An EC tracer method and combined EC tracer and K+ mass balance methods were used to estimate the contributions from secondary formation and biomass burning, respectively. High secondary organic carbon (SOC) concentrations were found in the autumn and winter due to low temperatures, which are favorable for the absorption and condensation of semi-volatile organic compounds on existing particles. High correlations were found between the estimated SOC in PM2.5 and the observed OOA (oxidized organic aerosol) in PM1; thus, the method proved to be effective and reliable. The annual average OCBiomass burning (OCbb) contribution to the total OC concentration was 18.4%, suggesting that biomass

  4. Impact of emission control on regional air quality: an observational study of air pollutants before, during and after the Beijing Olympic Games.

    PubMed

    Wang, Shulan; Gao, Jian; Zhang, Yuechong; Zhang, Jingqiao; Cha, Fahe; Wang, Tao; Ren, Chun; Wang, Wenxing

    2014-01-01

    An observational study on trace gases and PM2.5 was conducted at three sites in and around Beijing, during the Olympic season from 2007 to 2009. Air quality improved significantly during the Olympic Games due to the special emission control measures. However, concentrations of the primary pollutants and PM were found to have risen significantly after the Games. Although the major O3 precursors (NO(x) and VOCs) were well controlled during the Olympic season, O3 was still found to be the highest in 2008, based on the data of ground-based observation. All this information suggests that while control of regional emissions for the Beijing Olympic Games did improved the air quality in Beijing, more efforts will be needed for the continuous improvement of regional air quality, especially for significant reductions of O3 and fine particulate pollution, and not only in Beijing, but also in the Beijing-Tianjin-Hebei region. PMID:24649704

  5. Granulometric and magnetic properties of deposited particles in the Beijing subway and the implications for air quality management.

    PubMed

    Cui, Guipeng; Zhou, Liping; Dearing, John

    2016-10-15

    The subway system is an important traffic facility in Beijing and its internal air quality is an environmental issue that could potentially affect millions of people every day. Due to the intrinsic nature of rail abrasion in subway tunnels, iron-containing particles can be generated and become suspended in the subway environment. While some studies (e.g. Li et al., 2006) have monitored the in-train levels of PM2.5 (particles<2.5μm), there is a lack of systematic assessment of the concentration and characteristics of iron-containing particles in the Beijing subway system. Here we report results of a study on the granulometric and magnetic properties of deposited particle samples collected at different localities of the Beijing subway system. Our results show that the subway samples are characterized by the presence of fine particles. Volume proportions of 6.1±1.3% for particles<2.5μm and 27.5±6.1% for particles<10μm are found in the bulk subway samples. These samples exhibit a strong magnetic signal, which is approximately two orders of magnitude higher than that in naturally deposited particles collected in Beijing. Fine grained ferromagnetic and ferrimagnetic minerals (e.g. iron and magnetite, respectively) are identified from mineral magnetic measurements and scanning electric microscopy. The samples collected from the Beijing stations with platform screen doors are found to be magnetically stronger and finer than those without them, suggesting that platform screen doors have failed to block the fine iron-containing particles released from the rail tunnel. Given the potential health consequences of fine suspended iron-containing particles, our results have important implications for air quality management in the Beijing subway system. PMID:27372891

  6. The Beijing Geothermal System, PR China: Natural state and exploitation modelling study of a low temperature basement aquifer system

    SciTech Connect

    Hochstein, M.P.; Zhongke, Yang

    1988-01-01

    Computer modeling of the Beijing low temperature, basement aquifer system has shown that secular natural convection of meteoric waters down to depths greater than 5 km can produce a temperature field which is similar to that observed in deep wells. Secular convection occurs within a crustal block with the approximate dimensions of 45 km {times} 60 km {times} 10 km; the Beijing system is probably one of the largest secular convecting systems described so far. It is driven entirely by the crustal heatflow which appears to be slightly lower (i.e. 54 mW/m{sup 2}) than the average continental heat flux. Several geophysical implications are described.

  7. Reconstruction de la surface de Fermi dans l'etat normal d'un supraconducteur a haute Tc: Une etude du transport electrique en champ magnetique intense

    NASA Astrophysics Data System (ADS)

    Le Boeuf, David

    Des mesures de resistance longitudinale et de resistance de Hall en champ magnetique intense transverse (perpendiculaire aux plans CuO2) ont ete effectuees au sein de monocristaux de YBa2Cu3Oy (YBCO) demacles, ordonnes et de grande purete, afin d'etudier l'etat fondamental des supraconducteurs a haute Tc dans le regime sous-dope. Cette etude a ete realisee en fonction du dopage et de l'orientation du courant d'excitation J par rapport a l'axe orthorhombique b de la structure cristalline. Les mesures en champ magnetique intense revelent par suppression de la supraconductivite des oscillations magnetiques des resistances longitudinale et de Hall dans YBa2Cu 3O6.51 et YBa2Cu4O8. La conformite du comportement de ces oscillations quantiques au formalisme de Lifshitz-Kosevich, apporte la preuve de l'existence d'une surface de Fermi fermee a caractere quasi-2D, abritant des quasiparticules coherentes respectant la statistique de Fermi-Dirac, dans la phase pseudogap d'YBCO. La faible frequence des oscillations quantiques, combinee avec l'etude de la partie monotone de la resistance de Hall en fonction de la temperature indique que la surface de Fermi d'YBCO sous-dope comprend une petite poche de Fermi occupee par des porteurs de charge negative. Cette particularite de la surface de Fermi dans le regime sous-dope incompatible avec les calculs de structure de bande est en fort contraste avec la structure electronique presente dans le regime surdope. Cette observation implique ainsi l'existence d'un point critique quantique dans le diagramme de phase d'YBCO, au voisinage duquel la surface de Fermi doit subir une reconstruction induite par l'etablissement d'une brisure de la symetrie de translation du reseau cristallin sous-jacent. Enfin, l'etude en fonction du dopage de la resistance de Hall et de la resistance longitudinale en champ magnetique intense suggere qu'un ordre du type onde de densite (DW) est responsable de la reconstruction de la surface de Fermi. L'analogie de

  8. Concentration and size distribution of viable bioaerosols during non-haze and haze days in Beijing.

    PubMed

    Gao, Min; Qiu, Tianlei; Jia, Ruizhi; Han, Meilin; Song, Yuan; Wang, Xuming

    2015-03-01

    Accumulation of airborne particulate matter (PM) has profoundly affected the atmospheric environment of Beijing, China. Although studies on health risks have increased, characterization of specific factors that contribute to increased health risks remains an area of needed exploration. Chemical composition studies on PM can readily be found in the literature but researches on biological composition are still limited. In this study, the concentration and size distribution of viable airborne bacteria and fungi were determined in the atmosphere from May to July 2013 in Beijing, China. Samples were collected during non-haze days and haze days based on the value of air quality index (AQI) PM2.5. Multiple linear regression results indicated that concentrations of viable bioaerosol exhibited a negative correlation with PM2.5 (AQI) ranging from 14 to 452. There was a little difference in size distribution of bioaerosol between non-haze and haze days that all airborne bacteria showed skewed trends toward larger sizes and airborne fungi followed a Gaussian distribution. Spearman's correlation analysis showed that a fraction of bioaerosol with fine and coarse particles had negative and positive relations with PM2.5 (AQI), respectively. Moreover, the temporal variation of d g (aerodynamic diameter) of bioaerosol with PM2.5 (AQI) fluctuated from 9:00 to 21:00, which suggested that their deposition pattern would vary during a day. The primary research in this study implied that aerodynamic size variation should be considered in assessing the bioaerosol exposure during haze weather. PMID:25300183

  9. Preliminary Assessment of Health Risks of Potentially Toxic Elements in Settled Dust over Beijing Urban Area

    PubMed Central

    Wan, Dejun; Zhan, Changlin; Yang, Guanglin; Liu, Xingqi; Yang, Jinsong

    2016-01-01

    To examine levels, health risks, sources, and spatial distributions of potentially toxic elements in settled dust over Beijing urban area, 62 samples were collected mostly from residential building outdoor surfaces, and their <63 μm fractions were measured for 12 potentially toxic elements. The results show that V, Cr, Mn, Co, Ni, and Ba in dust are from predominantly natural sources, whereas Cu, Zn, As, Cd, Sb, and Pb mostly originate from anthropogenic sources. Exposure to these elements in dust has significant non-cancer risks to children but insignificant to adults. Cancer risks of Cr, Co, Ni, As, and Cd via inhalation and dermal contact are below the threshold of 10−6–10−4 but As via dust ingestion shows a tolerable risk. The non-cancer risks to children are contributed mainly (75%) by As, Pb, and Sb, and dominantly (92%) via dust ingestion, with relatively higher risks mainly occurring in the eastern and northeastern Beijing urban areas. Although Cd, Zn, and Cu in dust are heavily affected by anthropogenic sources, their health risks are insignificant. Source appointments suggest that coal burning emissions, the dominant source of As, are likely the largest contributors to the health risk, and traffic-related and industrial emissions are also important because they contribute most of the Pb and Sb in dust. PMID:27187427

  10. Predominance of modern Mycobacterium tuberculosis strains and active transmission of Beijing sublineage in Jayapura, Indonesia Papua.

    PubMed

    Chaidir, Lidya; Sengstake, Sarah; de Beer, Jessica; Oktavian, Antonius; Krismawati, Hana; Muhapril, Erfin; Kusumadewi, Inri; Annisa, Jessi; Anthony, Richard; van Soolingen, Dick; Achmad, Tri Hanggono; Marzuki, Sangkot; Alisjahbana, Bachti; van Crevel, Reinout

    2016-04-01

    Mycobacterium tuberculosis genotype distribution is different between West and Central Indonesia, but there are no data on the most Eastern part, Papua. We aimed to identify the predominant genotypes of M. tuberculosis responsible for tuberculosis in coastal Papua, their transmission, and the association with patient characteristics. A total of 199 M. tuberculosis isolates were collected. Spoligotyping was applied to describe the population structure of M. tuberculosis, lineage identification was performed using a combination of lineage-specific markers, and genotypic clusters were identified using a combination of 24-locus-MIRU-VNTR and spoligotyping. A high degree of genetic diversity was observed among isolates based on their spoligopatterns. Strains from modern lineage 4 made up almost half of strains (46.9%), being more abundant than the ancient lineage 1 (33.7%), and modern lineage 2 (19.4%). Thirty-five percent of strains belonged to genotypic clusters, especially strains in the Beijing genotype. Previous TB treatment and mutations associated with drug resistance were more common in patients infected with strains of the Beijing genotype. Papua shows a different distribution of M. tuberculosis genotypes compared to other parts of Indonesia. Clustering and drug resistance of modern strains recently introduced to Papua may contribute to the high tuberculosis burden in this region. PMID:26825253

  11. A Case-Control Study of Risk Factors Associated with Scrub Typhus Infection in Beijing, China

    PubMed Central

    Zhang, Liqin; Dou, Xiangfeng; Wang, Xiaomei; Li, Weihong; Zhang, Xiuchun; Sun, Yulan; Guan, Zengzhi; Li, Xinyu; Wang, Quanyi

    2013-01-01

    To investigate the risk factors of scrub typhus infection in Beijing, China, a case-control study was carried out. Cases (n = 56) were defined as persons who were diagnosed by PCR and serological method within three years. Three neighborhood control subjects were selected by matching for age and occupation. Living at the edge of the village, living in the houses near grassland, vegetable field or ditch, house yard without cement floor, piling weeds in the house or yard, all of these were risk factors for scrub typhus infection. Working in vegetable fields and hilly areas, and harvesting in autumn posed the highest risks, with odds ratios (ORs) and 95% confidence intervals (CIs) of 3.7 (1.1–11.9), 8.2 (1.4–49.5), and 17.2 (5.1–57.9), respectively. These results would be useful for the establishment of a detail control strategy for scrub typhus infection in Beijing, China. PMID:23691083

  12. Polycyclic aromatic hydrocarbons in urban green spaces of Beijing: concentration, spatial distribution and risk assessment.

    PubMed

    Zhang, Juan; Wu, Jianzhi; Liu, Yan

    2016-09-01

    A comprehensive investigation of the levels, spatial distribution of polycyclic aromatic hydrocarbons (PAHs) in urban green space soils of Beijing, China, was conducted, and the potential human health risks associated with the levels observed were addressed. The objective of this study was to determine concentration, spatial distribution, and health risk of 15 PAHs in 121 surface soil (0-5 cm) samples collected from four types of green space, such as park green space (PGS), roadside green space (RDS), residential green space (RGS), and attached green space (AGS). Results showed that the highest concentrations of 15 PAHs was in soils of RDS, followed by RGS, PGS, and AGS. The level of PAHs pollution was seriously and mainly distributed in the central and southwest of the city. Incremental lifetime cancer risks (ILCRs) associated with exposures to PAHs in soil was calculated separately for children and adults under normal and extreme conditions. The results showed that ILCRs for urban green space soil of Beijing were low under normal conditions. But individual samples are seriously polluted, and its potential health risks cannot be ignored. PMID:27502522

  13. The Effects of Weather Factors on Hand, Foot and Mouth Disease in Beijing

    NASA Astrophysics Data System (ADS)

    Dong, Weihua; Li, Xian'En; Yang, Peng; Liao, Hua; Wang, Xiaoli; Wang, Quanyi

    2016-01-01

    The morbidity and mortality of hand, foot and mouth disease (HFMD) are increasing in Beijing, China. Previous studies have indicated an association between incidents of HFMD and weather factors. However, the seasonal influence of these factors on the disease is not yet understood, and their relationship with the enterovirus 71 (EV71) and Coxsackie virus A16 (CV-A16) viruses are not well documented. We analysed 84,502 HFMD cases from 2008 to 2011 in Beijing to explore the seasonal influence of weather factors (average temperature [AT], average relative humidity [ARH], total precipitation [TP] and average wind speed [AWS]) on incidents of HFMD by using a geographically weighted regression (GWR) model. The results indicated that weather factors differ significantly in their influence on HFMD depending on the season. AT had the greatest effect among the four weather factors, and while the influence of AT and AWS was greater in the summer than in the winter, the influence of TP was positive in the summer and negative in the winter. ARH was negatively correlated with HFMD. Also, we observed more EV71-associated cases than CV-A16 but there is no convincing evidence to show significant differences between the influences of the weather factors on EV71 and CV-A16.

  14. Residents’ Preferences for Household Kitchen Waste Source Separation Services in Beijing: A Choice Experiment Approach

    PubMed Central

    Yuan, Yalin; Yabe, Mitsuyasu

    2014-01-01

    A source separation program for household kitchen waste has been in place in Beijing since 2010. However, the participation rate of residents is far from satisfactory. This study was carried out to identify residents’ preferences based on an improved management strategy for household kitchen waste source separation. We determine the preferences of residents in an ad hoc sample, according to their age level, for source separation services and their marginal willingness to accept compensation for the service attributes. We used a multinomial logit model to analyze the data, collected from 394 residents in Haidian and Dongcheng districts of Beijing City through a choice experiment. The results show there are differences of preferences on the services attributes between young, middle, and old age residents. Low compensation is not a major factor to promote young and middle age residents accept the proposed separation services. However, on average, most of them prefer services with frequent, evening, plastic bag attributes and without instructor. This study indicates that there is a potential for local government to improve the current separation services accordingly. PMID:25546279

  15. Residents' preferences for household kitchen waste source separation services in Beijing: a choice experiment approach.

    PubMed

    Yuan, Yalin; Yabe, Mitsuyasu

    2015-01-01

    A source separation program for household kitchen waste has been in place in Beijing since 2010. However, the participation rate of residents is far from satisfactory. This study was carried out to identify residents' preferences based on an improved management strategy for household kitchen waste source separation. We determine the preferences of residents in an ad hoc sample, according to their age level, for source separation services and their marginal willingness to accept compensation for the service attributes. We used a multinomial logit model to analyze the data, collected from 394 residents in Haidian and Dongcheng districts of Beijing City through a choice experiment. The results show there are differences of preferences on the services attributes between young, middle, and old age residents. Low compensation is not a major factor to promote young and middle age residents accept the proposed separation services. However, on average, most of them prefer services with frequent, evening, plastic bag attributes and without instructor. This study indicates that there is a potential for local government to improve the current separation services accordingly. PMID:25546279

  16. IASI measurements of tropospheric ozone over Chinese megacities: Beijing, Shanghai, and Hong Kong

    NASA Astrophysics Data System (ADS)

    Dufour, G.; Eremenko, M.; Orphal, J.; Flaud, J.-M.

    2009-11-01

    IASI observations of tropospheric ozone over Beijing, Shanghai and Hong Kong during one year have been analysed, demonstrating the capability of space-borne infrared nadir measurements to probe both seasonal and daily variations of lower tropospheric ozone around megacities on the regional scale. The monthly variations of lower tropospheric ozone retrieved from IASI show the influence of the Asian summer monsoon that brings clean air masses from the Pacific during summer. They exhibit indeed a sharp ozone maximum in late spring and early summer (May-June) followed by a summer minimum. The time periods and the intensities of the maxima and of the decreases are latitude-dependent: they are more pronounced in Hong Kong and Shanghai than in Beijing. Moreover, IASI provides the opportunity to follow the spatial variations of ozone over the surroundings of each megacity as well as its daily variability. We show indeed that the large lower tropospheric ozone amounts observed with IASI are consistent with the highest population density distribution in each region, thus suggesting the anthropogenic origin of the large ozone amounts observed. Finally an analysis of the mean daily ozone profiles over each region for selected periods with high ozone events shows that the high ozone amounts observed during winter are likely related to descents of ozone-rich air from the stratosphere whereas in spring and summer the tropospheric ozone is likely enhanced by photochemical production in polluted areas and/or in fire plumes.

  17. [Pollution characteristics of platinum group elements in road dust in central urban area of Beijing].

    PubMed

    Xu, Ling-Ling; Gao, Bo; Lu, Jin; Zhou, Huai-Dong; Hao, Hong; Wang, Xiao-Jun

    2011-03-01

    In order to survey platinum group elements (PGEs) contamination in central urban area of Beijing, dust samples were collected from the second ring road in December 2009. The road samples were digested with aqua regia and separated and purified with cation exchange resin, and the resulting solutions were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The results showed that the concentrations of Pd, Pt and Rh in road dust ranged from 17.40-458.75 ng x g(-1) (126.66 ng x g(-1)), 10.04-182.89 ng x g(-1) (65.25 ng x g(-1)), 4.00-68.04 ng x g(-1) (22.67 ng x g(-1)) respectively. In comparison with international cities, Pd and Rh concentrations in Beijing road dust were middle level and Pt concentration was lower. Pd concentration was rapidly increased in recent years. The concentrations of PGEs in four locations of the second ring road were arranged in the following order: West approximately East > North > South, which were controlled with the traffic intensity. Size partitioning indicated that the 0.125-0.25 mm fraction had the higher PGEs concentrations than other fractions and the < 0.063 mm fraction had the lower PGEs concentration. These data suggest that autocatalyst PGEs flux estimates into the environment will be significantly underestimated if only a fine grain size fraction (< 0.063 mm) is analyzed. PMID:21634172

  18. Dynamic modeling of tourism by stochastic method: a case of the Beijing-Tianjin-Hebei region

    NASA Astrophysics Data System (ADS)

    Dai, Juan; Zhang, Shihui; Xue, Chongsheng

    2009-10-01

    As an efficient way to stimulate the growth of economy, tourism is promoted by most counties allover the world, and has become one of the world's largest and fastest-growing industries. Essentially, tourism is a spatiotemporal system, with tourist attractions located in different geographic areas and tourist flows exchanging between different geographic regions. In this paper, we present a dynamic model for the simulation of tourism and tourist's activities in the context of GIS and stochastic method, using a case of the Beijing-Tianjin-Hebei region. The model is developed on stochastic method and multiple geospatial data sources. In the model, the spatiotemporal behavior of tourist on the Earth's Surface is governed by the evolution rules, which are extracted from the researches on tourist's activities and executed via stochastic method and multiple geospatial data. By means of the model, we simulate the tourism in the Beijing-Tianjin- Hebei region, and find that there is good correspondence between the tourist arrivals calculated with the model and those obtained from the tourism statistics. This shows that the animated dynamic modeling of tourism based on geospatial data can be used as an indicator of the tourism in the realistic world, and is also can be embedded in the GIS applications.

  19. [Emission Characteristics of Vehicle Exhaust in Beijing Based on Actual Traffic Flow Information].

    PubMed

    Fan, Shou-bin; Tian, Ling-di; Zhang, Dong-xu; Qu, Song

    2015-08-01

    The basic data of traffic volume, vehicle type constitute and speed on road networks in Beijing was obtained fly modei simulation and field survey. Based on actual traffic flow information and. emission factors data with temporal and spatial distribution features, emission inventory of motor vehicle exhaust in Beijing was built on the ArcGIS platform, meanwhile, the actual road emission characteristics and spatial distribution of the pollutant emissions were analyzed. The results showed that the proportion of passenger car was higher than 89% on each type of road in the urban, and the proportion of passenger car was the highest in suburban roads as well while the pickup truck, medium truck, heavy truck, motorbus, tractor and motorcycle also occupied a certain proportion. There was a positive correlation between the pollutant emission intensity and traffic volume, and the emission intensity was generally higher in daytime than nighttime, but the diurnal variation trend of PM emission was not clear for suburban roads and the emission intensity was higher in nighttime than daytime for highway. The emission intensities in urban area, south, southeast and northeast areas near urban were higher than those in the western and northern mountainous areas with lower density of road network. The ring roads in urban and highways in suburban had higher emission intensity because of the heavy traffic volume. PMID:26592000

  20. A Long-Term Prediction Model of Beijing Haze Episodes Using Time Series Analysis.

    PubMed

    Yang, Xiaoping; Zhang, Zhongxia; Zhang, Zhongqiu; Sun, Liren; Xu, Cui; Yu, Li

    2016-01-01

    The rapid industrial development has led to the intermittent outbreak of pm2.5 or haze in developing countries, which has brought about great environmental issues, especially in big cities such as Beijing and New Delhi. We investigated the factors and mechanisms of haze change and present a long-term prediction model of Beijing haze episodes using time series analysis. We construct a dynamic structural measurement model of daily haze increment and reduce the model to a vector autoregressive model. Typical case studies on 886 continuous days indicate that our model performs very well on next day's Air Quality Index (AQI) prediction, and in severely polluted cases (AQI ≥ 300) the accuracy rate of AQI prediction even reaches up to 87.8%. The experiment of one-week prediction shows that our model has excellent sensitivity when a sudden haze burst or dissipation happens, which results in good long-term stability on the accuracy of the next 3-7 days' AQI prediction. PMID:27597861

  1. Impacts of radiance data assimilation on the Beijing 7.21 heavy rainfall

    NASA Astrophysics Data System (ADS)

    Xie, Yanhui; Xing, Jianyong; Shi, Jiancheng; Dou, Youjun; Lei, Yonghui

    2016-03-01

    Precipitation simulation during the Beijing heavy rainfall event on 21 July 2012 has been investigated in this study. A control run of the Weather Research and Forecasting (WRF) model can roughly simulate the mesoscale features and spatial heterogeneity of precipitation over North China, but it cannot capture the locations, intensity and timing of maximum rainfall over the Beijing area compared with ground observations. To gain better initial conditions in the performance of the mesoscale model, Advanced Microwave Sounding Unit (AMSU) radiance data assimilation was carried out. The spatial distribution and intensity of precipitation have been significantly improved. In particular, data assimilation of Advanced Microwave Sounding Unit-A only has similar impacts on heavy rainfall simulation as the AMSU data assimilation run. Data assimilation of Advanced Microwave Sounding Unit-B only has improved the spatial distribution of heavy rainfall, but it has little impact on the intensity of rainfall. However, the timing of heavy rainfall in all simulations is about 5 to 6 h later than observations. Further analysis shows that the center and strength of the low-pressure system was not well simulated during the early development of heavy rainfall in the model. Results from radiance data assimilation suggest that improvement of the initial conditions plays a positive impact on heavy rainfall in 24 h simulation. Operational forecast system including satellite radiance data assimilation may improve heavy rainfall forecasting.

  2. Reduction of Aerosol Absorption in Beijing Since 2007 from MODIS and AERONET

    NASA Technical Reports Server (NTRS)

    Lyapustin, A.; Smirnov, A.; Holben, B.; Chin, M.; Streets, D. G.; Lu, Z.; Kahn, R.; Slutsker, I.; Laszlo, I.; Kondragunta, S.; Tanre, D.; Dubovik, O.; Goloub, P.; Chen, H.-B.; Sinyuk, A.; Wang, Y.; Korkin, S.

    2011-01-01

    An analysis of the time series of MODIS-based and AERONET aerosol records over Beijing reveals two distinct periods, before and after 2007. The MODIS data from both the Terra and Aqua satellites were processed with the new Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm. A comparison of MAIAC and AERONET AOT shows that whereas MAIAC consistently underestimated peak AOT values by 10-20% in the prior period, the bias mostly disappears after mid-2007. Independent analysis of the AERONET dataset reveals little or no change in the effective radii of the fine and coarse fractions and of the Angstrom exponent. At the same time, it shows an increasing trend in the single scattering albedo, by approx.0.02 in 9 years. As MAIAC was using the same aerosol model for the entire 2000-2010 period, the decrease in AOT bias after 2007 can be explained only by a corresponding decrease of aerosol absorption caused by a reduction in local black carbon emissions. The observed changes correlate in time with the Chinese government's broad measures to improve air quality in Beijing during preparations for the Summer Olympics of 2008.

  3. Reduction of Aerosol Absorption in Beijing Since 2007 from MODIS and AERONET

    NASA Technical Reports Server (NTRS)

    Lyapustin, A.; Smirnov, A.; Holben, B.; Chin, M.; Streets, D. G.; Lu, Z.; Kahn, R.; Slutsker, I.; Laszlo, I.; Kondragunta, S.; Tanre, D.; Dubovik, O.; Goloub, P.; Chen, H.-B.; Sinyuk, A.; Wang, Y.; Korkin, S.

    2011-01-01

    An analysis of the time series of MODIS-based and AERONET aerosol records over Beijing reveals two distinct periods, before and after 2007. The MODIS data from both the Terra and Aqua satellites were processed with the new Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm. A comparison of MAIAC and AERONET AOT shows that whereas MAIAC consistently underestimated peak AOT values by 10-20% in the prior period, the bias mostly disappears after mid- 2007. Independent analysis of the AERONET dataset reveals little or no change in the effective radii of the fine and coarse fractions and of the Angstrom exponent. At the same time, it shows an increasing trend in the single scattering albedo, by 0.02 in 9 years. As MAIAC was using the same aerosol model for the entire 2000-2010 period, the decrease in AOT bias after 2007 can be explained only by a corresponding decrease of aerosol absorption caused by a reduction in local black carbon emissions. The observed changes correlate in time with the Chinese government's broad measures to improve air quality in Beijing during preparations for the Summer Olympics of 2008.

  4. Comparison of Hourly PM2.5 Observations Between Urban and Suburban Areas in Beijing, China.

    PubMed

    Yao, Ling; Lu, Ning; Yue, Xiafang; Du, Jia; Yang, Cundong

    2015-10-01

    Hourly PM2.5 observations collected at 12 stations over a 1-year period are used to identify variations between urban and suburban areas in Beijing. The data demonstrates a unique monthly variation form, as compared with other major cities. Urban areas suffer higher PM2.5 concentration (about 92 μg/m³) than suburban areas (about 77 μg/m³), and the average PM2.5 concentration in cold season (about 105 μg/m³) is higher than warm season (about 78 μg/m³). Hourly PM2.5 observations exhibit distinct seasonal, diurnal and day-of-week variations. The diurnal variation of PM2.5 is observed with higher concentration at night and lower value at daytime, and the cumulative growth of nighttime (22:00 p.m. in winter) PM2.5 concentration maybe due to the atmospheric stability. Moreover, annual average PM2.5 concentrations are about 18 μg/m³ higher on weekends than weekdays, consistent with driving restrictions on weekdays. Additionally, the nighttime peak in weekdays (21:00 p.m.) is one hour later than weekends (20:00 p.m.) which also shows the evidence of human activity. These observed facts indicate that the variations of PM2.5 concentration between urban and suburban areas in Beijing are influenced by complex meteorological factors and human activities. PMID:26426035

  5. Reduction of aerosol absorption in Beijing since 2007 from MODIS and AERONET

    NASA Astrophysics Data System (ADS)

    Lyapustin, A.; Smirnov, A.; Holben, B.; Chin, M.; Streets, D. G.; Lu, Z.; Kahn, R.; Slutsker, I.; Laszlo, I.; Kondragunta, S.; Tanré, D.; Dubovik, O.; Goloub, P.; Chen, H.-B.; Sinyuk, A.; Wang, Y.; Korkin, S.

    2011-05-01

    An analysis of the time series of MODIS-based and AERONET aerosol records over Beijing reveals two distinct periods, before and after 2007. The MODIS data from both the Terra and Aqua satellites were processed with the new Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm. A comparison of MAIAC and AERONET AOT shows that whereas MAIAC consistently underestimated peak AOT values by 10-20% in the prior period, the bias mostly disappears after mid-2007. Independent analysis of the AERONET dataset reveals little or no change in the effective radii of the fine and coarse fractions and of the Ångström exponent. At the same time, it shows an increasing trend in the single scattering albedo, by ˜0.02 in 9 years. As MAIAC was using the same aerosol model for the entire 2000-2010 period, the decrease in AOT bias after 2007 can be explained only by a corresponding decrease of aerosol absorption caused by a reduction in local black carbon emissions. The observed changes correlate in time with the Chinese government's broad measures to improve air quality in Beijing during preparations for the Summer Olympics of 2008.

  6. The Large Scale Machine Learning in an Artificial Society: Prediction of the Ebola Outbreak in Beijing.

    PubMed

    Zhang, Peng; Chen, Bin; Ma, Liang; Li, Zhen; Song, Zhichao; Duan, Wei; Qiu, Xiaogang

    2015-01-01

    Ebola virus disease (EVD) distinguishes its feature as high infectivity and mortality. Thus, it is urgent for governments to draw up emergency plans against Ebola. However, it is hard to predict the possible epidemic situations in practice. Luckily, in recent years, computational experiments based on artificial society appeared, providing a new approach to study the propagation of EVD and analyze the corresponding interventions. Therefore, the rationality of artificial society is the key to the accuracy and reliability of experiment results. Individuals' behaviors along with travel mode directly affect the propagation among individuals. Firstly, artificial Beijing is reconstructed based on geodemographics and machine learning is involved to optimize individuals' behaviors. Meanwhile, Ebola course model and propagation model are built, according to the parameters in West Africa. Subsequently, propagation mechanism of EVD is analyzed, epidemic scenario is predicted, and corresponding interventions are presented. Finally, by simulating the emergency responses of Chinese government, the conclusion is finally drawn that Ebola is impossible to outbreak in large scale in the city of Beijing. PMID:26457078

  7. Humidity plays an important role in the PM₂.₅ pollution in Beijing.

    PubMed

    Cheng, Yuan; He, Ke-bin; Du, Zhen-yu; Zheng, Mei; Duan, Feng-kui; Ma, Yong-liang

    2015-02-01

    Heavily-polluted PM₂.₅ (fine particulate matter) episodes frequently impacting Beijing, especially during winter, have become a substantial concern. We found that during winter, the daily variation of PM2.5 in Beijing tracked the pattern of relative humidity (RH). With the increase of PM₂.₅ (or RH), water-soluble components (especially inorganic ions) became more abundant, and the water-soluble organic carbon to organic carbon ratios increased. The nitrate to sulfate ratios also exhibited dependence on RH, and were higher than those measured about a decade ago, consistent with the increasing trend of nitrogen oxides emissions. Surprisingly, the ratios of water-insoluble organic carbon to elemental carbon showed significant increase at high RH levels, presumably indicating the formation of secondary organic aerosol that is not soluble in water. In addition, humid winters were occasionally identified during 1996-2013 which are expected to be favorable for the formation of air pollution episodes with high PM₂.₅ concentrations. PMID:25497308

  8. Three-scale input-output modeling for urban economy: Carbon emission by Beijing 2007

    NASA Astrophysics Data System (ADS)

    Chen, G. Q.; Guo, Shan; Shao, Ling; Li, J. S.; Chen, Zhan-Ming

    2013-09-01

    For urban economies, an ecological endowment embodiment analysis has to be supported by endowment intensities at both the international and domestic scales to reflect the international and domestic imports of increasing importance. A three-scale input-output modeling for an urban economy to give nine categories of embodiment fluxes is presented in this paper by a case study on the carbon dioxide emissions by the Beijing economy in 2007, based on the carbon intensities for the average world and national economies. The total direct emissions are estimated at 1.03E+08 t, in which 91.61% is energy-related emissions. By the modeling, emissions embodied in fixed capital formation amount to 7.20E+07 t, emissions embodied in household consumption are 1.58 times those in government consumption, and emissions in gross capital formation are 14.93% more than those in gross consumption. As a net exporter of carbon emissions, Beijing exports 5.21E+08 t carbon embodied in foreign imported commodities and 1.06E+08 t in domestic imported commodities, while emissions embodied in foreign and domestic imported commodities are 3.34E+07 and 1.75E+08 t respectively. The algorithm presented in this study is applicable to the embodiment analysis of other environmental resources for regional economies characteristic of multi-scales.

  9. [Pollution Characteristics of Aldehydes and Ketones Compounds in the Exhaust of Beijing Typical Restaurants].

    PubMed

    Cheng, Jing-chen; Cui, Tong; He, Wan-qing; Nie, Lei; Wang, Jun-ling; Pan, Tao

    2015-08-01

    Aldehydes and ketones compounds, as one of the components in the exhaust of restaurants, are a class of volatile organic compounds (VOCs) with strong chemical reactivity. However, there is no systematic study on aldehydes and ketones compounds in the exhaust of restaurants. To further clarify the food source emission levels of aldehydes and ketones compounds and controlling measures, to access city group catering VOCs emissions control decision-making basis, this study selected 8 Beijing restaurants with different types. The aldehydes and ketones compounds were sampled using DNPH-silica tube, and then ultra performance liquid chromatography was used for quantitative measurement. The aldehydes and ketones concentrations of reference volume condition from 8 restaurants in descending order were Roasted Duck restaurant, Chinese Style Barbecue, Home Dishes, Western Fast-food, School Canteen, Chinese Style Fast-food, Sichuan Cuisine, Huaiyang Cuisine. The results showed that the range of aldehydes and ketones compounds (C1-C9) concentrations of reference volume condition in the exhaust of restaurants was 115.47-1035.99 microg x m(-3). The composition of aldehydes and ketones compounds in the exhaust of sampled restaurants was obviously different. The percentages of C1-C3 were above 40% in the exhaust from Chinese style restaurants. Fast food might emit more C4-C9 aldehydes and ketones compounds. From the current situation of existing aldehydes and ketones compounds control, the removal efficiency of high voltage electrostatic purifiers widely used in Beijing is limited. PMID:26591999

  10. Accumulation and distribution characteristics of platinum group elements in roadside dusts in Beijing, China.

    PubMed

    Gao, Bo; Yu, Yanke; Zhou, Huaidong; Lu, Jin

    2012-06-01

    The concentrations, distribution, and accumulation of platinum group elements (PGEs) were investigated in roadside dusts collected in four different foundational areas in Beijing during February to May 2010. The results showed that PGE levels in all samples were above the average upper crust values, with mean concentrations of 57.5 ng · g(-1) Pd, 28.2 ng · g(-1) Pt, and 9.8 ng · g(-1) Rh, respectively. Palladium concentration has increased rapidly in recent years. The rank of PGE levels in four different functional regions for roadside dusts was: heavy density traffic area > residential area > educational area > tourism area. Palladium, Pt, and Rh concentrations in dusts showed strong positive correlations, indicating a common traffic-related source of these metals. Meanwhile, PGEs in these samples were not correlated with other traffic-related metals except for Cr. The average PGE ratios of road dusts from Beijing were consistent with those in Germany and Western Australia, but lower than those in the United States and Mexico, indicating that various catalyst productions were used in different countries. In addition, grain-size partitioning of PGEs in dusts indicated that concentrations of PGEs differed from one particle size to another. The coarse fraction had higher PGE concentrations than the fine fraction in roadside dusts. These results showed that autocatalyst PGE contamination estimates in the environment would be significantly underestimated if only a fine-grain size fraction (<0.063 mm) is analyzed. PMID:22505271

  11. Residues and Characteristics of Organochlorine Pesticides in the Surface Water in the Suburb of Beijing

    NASA Astrophysics Data System (ADS)

    CHEN, Jiawei; LIU, Chen; YANG, Zhongfang; WANG, Jiyuan

    Organochlorine Pesticides (OCPs), such as DDT and HCH, have stable chemical properties and less biodegradability. As a kind of persistent organic pollutants, they have high risk to the environment and human health. Although DDT and HCH have been prohibited in China since 1983, they are still found in some soil and water nowadays. Water resource is very important in natural environment and essential for agriculture. The existence of OCPs in some surface water in Beijing has been detected with different levels according to previous investigations. In recent years, many measures have been taken to control the pollution and to monitor the environment, and more attention has been paid to the status of surface water today. In this study, the water samples were collected from the Wenyu, Beiyun, Yanqing, Fangshan, Changping, and Shunyi Rivers in the suburb of Beijing, and the residues and characteristics of DDT and HCH were studied. The results showed that the contents of DDTs and HCHs were ND-13.98 ng/L and 3.87-146.42 ng/L, respectively. According to the indicators of the ratio values of (DDD+DDE)/DDT and α-HCH/γ-HCH, the source of pollution and its potential risk are also discussed in this article.

  12. The Effects of Weather Factors on Hand, Foot and Mouth Disease in Beijing

    PubMed Central

    Dong, Weihua; Li, Xian’en; Yang, Peng; Liao, Hua; Wang, Xiaoli; Wang, Quanyi

    2016-01-01

    The morbidity and mortality of hand, foot and mouth disease (HFMD) are increasing in Beijing, China. Previous studies have indicated an association between incidents of HFMD and weather factors. However, the seasonal influence of these factors on the disease is not yet understood, and their relationship with the enterovirus 71 (EV71) and Coxsackie virus A16 (CV-A16) viruses are not well documented. We analysed 84,502 HFMD cases from 2008 to 2011 in Beijing to explore the seasonal influence of weather factors (average temperature [AT], average relative humidity [ARH], total precipitation [TP] and average wind speed [AWS]) on incidents of HFMD by using a geographically weighted regression (GWR) model. The results indicated that weather factors differ significantly in their influence on HFMD depending on the season. AT had the greatest effect among the four weather factors, and while the influence of AT and AWS was greater in the summer than in the winter, the influence of TP was positive in the summer and negative in the winter. ARH was negatively correlated with HFMD. Also, we observed more EV71-associated cases than CV-A16 but there is no convincing evidence to show significant differences between the influences of the weather factors on EV71 and CV-A16. PMID:26755102

  13. Sublineages of Mycobacterium tuberculosis Beijing genotype strains and unfavorable outcomes of anti-tuberculosis treatment.

    PubMed

    Hang, Nguyen T L; Maeda, Shinji; Keicho, Naoto; Thuong, Pham H; Endo, Hiroyoshi

    2015-05-01

    The influence of Mycobacterium tuberculosis (MTB) lineages/sublineages on unfavorable tuberculosis (TB) treatment outcomes is poorly understood. We investigated the effects of Beijing genotype sublineages and other factors contributing to treatment outcome. Patients newly diagnosed with sputum smear-positive and culture-positive TB in Hanoi, Vietnam, participated in the study. After receiving anti-TB treatment, they were intensively followed up for the next 16 months. MTB isolates collected before treatment were subjected to drug susceptibility testing, and further analyzed to determine MTB (sub) lineages and their clonal similarities. Of 430 patients, 17 had treatment failure and 30 had TB recurrence. Rifampicin resistance was associated with treatment failure {adjusted odds ratio = 6.64 [95% confidence interval (CI), 1.48-29.73]}. The modern Beijing genotype was significantly associated with recurrent TB within 16 months [adjusted hazard ratio = 3.29 (95% CI, 1.17-9.27)], particularly after adjustment for the relevant antibiotic resistance. Human immunodeficiency virus coinfection and severity on chest radiographs were not significantly associated with unfavorable outcomes. Our findings provide further understanding of the influence of MTB strains on unfavorable treatment outcomes. Multiple risk factors should be considered for the optimal management of TB. PMID:25732626

  14. [Hydrology and pollution characteristics of urban runoff: Beijing as a sample].

    PubMed

    Dong, Xin; Du, Peng-Fei; Li, Zhi-Yi; Yu, Zheng-Rong; Wang, Rui; Huang, Jin-Liang

    2008-03-01

    The purpose of this study is identification and characterization of hydrological process of urban runoff, as well as concentration variation of pollutants in it. Samples were collected in 4 rainfall events in Beijing from Jun. 2006 to Aug. 2006. Hydrology and pollution of the rainfall-runoff process were analyzed on roof and road. Study results show that the shapes of hydrological curves of runoff, despite for a 5 - 20 min delay and a milder tendency, are similar to rainfall curves. Runoff coefficients of roof are 0.80 - 0.98, while 0.87 - 0.97 of road. Event mean concentrations (EMC) of pollutants are influenced by build-up and wash-off features, which leads to a higher concentration in road runoff than in roof runoff. Major pollutants that excess the water quality standards are COD, TN, and TP. Evident correlations (> 0.1) are found between pollutants. Correlation with particles are higher for COD and SO4(2-) (> 0.5), while lower for nutrients (<0.5). First flush effects (FFE) are found and affected by several factors, such as pollutant variety, types of land covers, and rainfall intensity. FFE are found more intense in SS, more frequently in road runoff, and more difficult to form for COD and nutrients with low rainfall intensity. Therefore, control of first period of runoff would be an effective approach for runoff management in Beijing. PMID:18649515

  15. The Beijing Twin Study (BeTwiSt): a longitudinal study of child and adolescent development.

    PubMed

    Chen, Jie; Li, Xinying; Zhang, Jianxin; Natsuaki, Misaki N; Leve, Leslie D; Harold, Gordon T; Chen, Zhiyan; Yang, Xiaodong; Guo, Fei; Zhang, Jie; Ge, Xiaojia

    2013-02-01

    Rates of emotional and behavioral problems among children and adolescents in China are increasing and represent a major public health concern. To investigate the etiology of such problems, including the effects and interplay of genes and environment, the Beijing Twin Study (BeTwiSt) was established. A representative sample of adolescent twins in Beijing (N = 1,387 pairs of adolescent twins, mostly between the ages of 10 and 18 years) was recruited and assessed longitudinally. Data collection included the following: emotional and behavioral problems (e.g., depressive symptoms, anxiety, delinquency, drinking, and smoking); family, peer, and school environments; stress; social and academic competence; cognitive traits (e.g., emotion suppression, rumination, and effortful control); and saliva samples for DNA genotyping and sequencing. The combination of quantitative and molecular genetic approaches and the timeliness of the project, with the sample residing in a region with a rapidly changing economic and cultural climate, are particular strengths of this study. Findings from this study are expected to help understanding of the etiological mechanisms underlying child and adolescent normal and abnormal development in regions undergoing substantial social, cultural, and economic changes. PMID:23177327

  16. Variations in ecological service value in Beijing from 1990 to 2006 based on remote sensing

    NASA Astrophysics Data System (ADS)

    Sun, Yonghua; Li, Xiaojuan; Gong, Huili; Wang, Yihan

    2009-09-01

    Ecological services are defined as the conditions and processes through which natural ecosystems and the species that comprise them, sustain and fulfill human life, or the goods and services provided by ecosystem which contribute to human welfare, both directly and indirectly. Ecological service value has been a hot topic in ecological economic research. Beijing, the capital of China, covers an area of more than 16,410 square kilometers and has a population of 14.93 million people. It's also a fast-growing city with rapid urbanization, which may significantly impact ecological services and functions. Such effects are difficult to quantify and are seldom taken into account in the policy making process. So this article tried a technical process for calculating the ecological service value based on remote sensing. Then the article estimated variations in ecological services value in response to land use changes in Beijing from 1990 to 2006, and provided useful information and advice to policy-making for sustainable development of ecological environment.

  17. Variations in ecological service value in Beijing from 1990 to 2006 based on remote sensing

    NASA Astrophysics Data System (ADS)

    Sun, Yonghua; Li, Xiaojuan; Gong, Huili; Wang, Yihan

    2010-11-01

    Ecological services are defined as the conditions and processes through which natural ecosystems and the species that comprise them, sustain and fulfill human life, or the goods and services provided by ecosystem which contribute to human welfare, both directly and indirectly. Ecological service value has been a hot topic in ecological economic research. Beijing, the capital of China, covers an area of more than 16,410 square kilometers and has a population of 14.93 million people. It's also a fast-growing city with rapid urbanization, which may significantly impact ecological services and functions. Such effects are difficult to quantify and are seldom taken into account in the policy making process. So this article tried a technical process for calculating the ecological service value based on remote sensing. Then the article estimated variations in ecological services value in response to land use changes in Beijing from 1990 to 2006, and provided useful information and advice to policy-making for sustainable development of ecological environment.

  18. Relationship between haze and acute cardiovascular, cerebrovascular, and respiratory diseases in Beijing.

    PubMed

    Zhang, Jin-Jun; Cui, Meng-Meng; Fan, Da; Zhang, De-Shan; Lian, Hui-Xin; Yin, Zhao-Yin; Li, Jin

    2015-03-01

    Haze is an atmospheric phenomenon in which dry particulate pollutants obscure the sky. Haze has been associated with chronic diseases, but its relationship with acute diseases is less clear. We aimed to determine the association between haze and acute cardiovascular, cerebrovascular, and respiratory diseases, in order to determine the influence of haze on human health. We compared the number of cases of acute cardiovascular, cerebrovascular, and respiratory diseases in Beijing Emergency Center between 2006 and 2013, with haze data from Beijing Observatory. The relationship between the number of hazy days and the number of cases of the above types of diseases was analyzed using univariate analyses. Both the number of cases and the number of hazy days showed a rising trend. The average number of cases per day for all three diseases was higher on hazy days than on non-hazy days. There was a positive correlation between the number of hazy days and the number of cases, and this correlation showed a hysteretic quality. Haze has an influence on acute cardiovascular (CVDs), cerebrovascular (CBDs), and respiratory system (RSDs) diseases. Haze seems to have an additive effect, since the associations between haze and number of cases were stronger in the following month than in the preceding month. The increasing trend in the number of hazy days might worsen the problem of haze-related diseases. PMID:25292298

  19. Cigarette smoking and its risk factors among elementary school students in Beijing.

    PubMed Central

    Zhu, B P; Liu, M; Shelton, D; Liu, S; Giovino, G A

    1996-01-01

    OBJECTIVES. This study investigated patterns of and risk factors for smoking among elementary school children in Beijing, China. METHODS. In 1988, anonymous questionnaires were administered to a multistage stratified cluster sample of 16996 students, aged mostly 10 to 12, in 479 fourth- to sixth-grade classes from 122 Beijing elementary schools. RESULTS. Approximately 28% of boys and 3% of girls had smoked cigarettes. The most frequently cited reasons for smoking initiation were "to imitate others' behavior" and "to see what it was like." Girls were more likely to get cigarettes from home than to purchase their own. Having close friends who smoked and being encouraged by close friends to smoke were strong risk factors for smoking. Smoking was also associated with lower parental socioeconomic status; having parents, siblings, or teachers who smoked; buying cigarettes for parents; performing poorly in school; and not believing that smoking is harmful to health. CONCLUSIONS. Gender differences in smoking prevalence among adolescents in China are larger than those among US teenagers, whereas the proximal risk factors for smoking are similar. Major efforts are needed to monitor and prevent smoking initiation among Chinese adolescents, particularly girls. PMID:8604762

  20. A Long-Term Prediction Model of Beijing Haze Episodes Using Time Series Analysis

    PubMed Central

    Zhang, Zhongqiu; Sun, Liren; Xu, Cui

    2016-01-01

    The rapid industrial development has led to the intermittent outbreak of pm2.5 or haze in developing countries, which has brought about great environmental issues, especially in big cities such as Beijing and New Delhi. We investigated the factors and mechanisms of haze change and present a long-term prediction model of Beijing haze episodes using time series analysis. We construct a dynamic structural measurement model of daily haze increment and reduce the model to a vector autoregressive model. Typical case studies on 886 continuous days indicate that our model performs very well on next day's Air Quality Index (AQI) prediction, and in severely polluted cases (AQI ≥ 300) the accuracy rate of AQI prediction even reaches up to 87.8%. The experiment of one-week prediction shows that our model has excellent sensitivity when a sudden haze burst or dissipation happens, which results in good long-term stability on the accuracy of the next 3–7 days' AQI prediction. PMID:27597861

  1. [Formation Mechanism of a Serious Pollution Event in January 2013 in Beijing].

    PubMed

    Cheng, Nian-liang; Li, Yun-ting; Zhang, Da-wei; Nie, Teng; Qiu, Qi-hong; Xu, Wen-shuai

    2015-04-01

    The weather conditions, atmospheric environmental background and formation mechanism of a heavy air pollution episode in Beijing City from January 9th to 15th, 2013 was preliminarily investigated by combining observed data and the WRF meteorology model. The results showed that the average concentration of PM2.5 was 323 μg x m(-3) from January 10th to 14th; the heavy pollution episode was closely related to the local meteorological conditions; the stable atmospheric circulation pattern provided favorable environmental field for the lasting of this heavy air pollution; small wind speed, high humidity, low PBL, and lasting temperature inversion were the main reasons for this heavy air pollution incident; further analysis showed that contributions of regional transmission to the receptor sites in Beijing were between 53% - 69% and there were obvious secondary conversions and transformations; overall regional transportation played a more important role during this serious air pollution incident; the meteorological conditions played a key role in the formation and destruction of the heavy air pollution, therefore we need to strengthen the study on early warning of heavy air pollution, in order to prevent and control the air heavy pollution effectively. PMID:26164885

  2. Preliminary Assessment of Health Risks of Potentially Toxic Elements in Settled Dust over Beijing Urban Area.

    PubMed

    Wan, Dejun; Zhan, Changlin; Yang, Guanglin; Liu, Xingqi; Yang, Jinsong

    2016-01-01

    To examine levels, health risks, sources, and spatial distributions of potentially toxic elements in settled dust over Beijing urban area, 62 samples were collected mostly from residential building outdoor surfaces, and their <63 μm fractions were measured for 12 potentially toxic elements. The results show that V, Cr, Mn, Co, Ni, and Ba in dust are from predominantly natural sources, whereas Cu, Zn, As, Cd, Sb, and Pb mostly originate from anthropogenic sources. Exposure to these elements in dust has significant non-cancer risks to children but insignificant to adults. Cancer risks of Cr, Co, Ni, As, and Cd via inhalation and dermal contact are below the threshold of 10(-6)-10(-4) but As via dust ingestion shows a tolerable risk. The non-cancer risks to children are contributed mainly (75%) by As, Pb, and Sb, and dominantly (92%) via dust ingestion, with relatively higher risks mainly occurring in the eastern and northeastern Beijing urban areas. Although Cd, Zn, and Cu in dust are heavily affected by anthropogenic sources, their health risks are insignificant. Source appointments suggest that coal burning emissions, the dominant source of As, are likely the largest contributors to the health risk, and traffic-related and industrial emissions are also important because they contribute most of the Pb and Sb in dust. PMID:27187427

  3. Monitoring land subsidence rates with permanent scatterers SAR interferometry: a case study of Beijing, China

    NASA Astrophysics Data System (ADS)

    Fan, Jun; Li, Xiaojuan; Yu, Jie; Wang, Yanbing; Wan, Yanyan; An, Zhihui

    2015-12-01

    The ground subsidence phenomenon is more serious in Beijing, large-scale land subsidence seriously threats to urban planning and construction and the safety of residents. In order to study the subsidence condition, it is necessary to monitor land subsidence. Choosing 28 scenes Envisat ASAR images covering Beijing city from December 2003 to March 2009, permanent scatterer SAR interferometry (PSI) technique was applied to obtained time series land subsidence information. Then the trend characteristics and factors of subsidence were analyzed, comparing land subsidence result with the groundwater data and geological structure data. Comparison between the PSI-derived subsidence rates and leveling data obtained shows that the result of PSI is agreed with the leveling data. The results indicate that the PSI technique is capable of providing high-level accuracy subsidence information. The results show that:(1) The deformation rates derived PSI ranging from -45.80 to 4.36mm/a;(2) In the study area, the serious subsidence areas distribute in Chaoyang District, Shunyi District, Tongzhou District and Pinggu District;(3) The subsidence tends to become more and more concentrated in 6 years from 2003 to 2009.

  4. Energy-Dominated Local Carbon Emissions in Beijing 2007: Inventory and Input-Output Analysis

    PubMed Central

    Guo, Shan; Liu, J. B.; Shao, Ling; Li, J. S.; An, Y. R.

    2012-01-01

    For greenhouse gas (GHG) emissions by Beijing economy 2007, a concrete emission inventory covering carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) is presented and associated with an input-output analysis to reveal the local GHG embodiment in final demand and trade without regard to imported emissions. The total direct GHG emissions amount to 1.06E + 08 t CO2-eq, of which energy-related CO2 emissions comprise 90.49%, non-energy-related CO2 emissions 6.35%, CH4 emissions 2.33%, and N2O emissions 0.83%, respectively. In terms of energy-related CO2 emissions, the largest source is coal with a percentage of 53.08%, followed by coke with 10.75% and kerosene with 8.44%. Sector 26 (Construction Industry) holds the top local emissions embodied in final demand of 1.86E + 07 t CO2-eq due to its considerable capital, followed by energy-intensive Sectors 27 (Transport and Storage) and 14 (Smelting and Pressing of Ferrous and Nonferrous Metals). The GHG emissions embodied in Beijing's exports are 4.90E + 07 t CO2-eq, accounting for 46.01% of the total emissions embodied in final demand. The sound scientific database totally based on local emissions is an important basis to make effective environment and energy policies for local decision makers. PMID:23193385

  5. Temporal Patterns in Fine Particulate Matter Time Series in Beijing: A Calendar View

    PubMed Central

    Liu, Jianzheng; Li, Jie; Li, Weifeng

    2016-01-01

    Extremely high fine particulate matter (PM2.5) concentration has become synonymous to Beijing, the capital of China, posing critical challenges to its sustainable development and leading to major public health concerns. In order to formulate mitigation measures and policies, knowledge on PM2.5 variation patterns should be obtained. While previous studies are limited either because of availability of data, or because of problematic a priori assumptions that PM2.5 concentration follows subjective seasonal, monthly, or weekly patterns, our study aims to reveal the data on a daily basis through visualization rather than imposing subjective periodic patterns upon the data. To achieve this, we conduct two time-series cluster analyses on full-year PM2.5 data in Beijing in 2014, and provide an innovative calendar visualization of PM2.5 measurements throughout the year. Insights from the analysis on temporal variation of PM2.5 concentration show that there are three diurnal patterns and no weekly patterns; seasonal patterns exist but they do not follow a strict temporal division. These findings advance current understanding on temporal patterns in PM2.5 data and offer a different perspective which can help with policy formulation on PM2.5 mitigation. PMID:27561629

  6. Beijing Sublineages of Mycobacterium tuberculosis Differ in Pathogenicity in the Guinea Pig

    PubMed Central

    Shanley, Crystal A.; Ackart, David; Jarlsberg, Leah G.; Shang, Shaobin; Obregon-Henao, Andres; Harton, Marisabel; Basaraba, Randall J.; Henao-Tamayo, Marcela; Barrozo, Joyce C.; Rose, Jordan; Kawamura, L. Masae; Coscolla, Mireia; Fofanov, Viacheslav Y.; Koshinsky, Heather; Gagneux, Sebastien; Hopewell, Philip C.; Ordway, Diane J.; Orme, Ian M.

    2012-01-01

    The Beijing family of Mycobacterium tuberculosis strains is part of lineage 2 (also known as the East Asian lineage). In clinical studies, we have observed that isolates from the sublineage RD207 of lineage 2 were more readily transmitted among humans. To investigate the basis for this difference, we tested representative strains with the characteristic Beijing spoligotype from four of the five sublineages of lineage 2 in the guinea pig model and subjected these strains to comparative whole-genome sequencing. The results of these studies showed that all of the clinical strains were capable of growing and causing lung pathology in guinea pigs after low-dose aerosol exposure. Differences between the abilities of the four sublineages to grow in the lungs of these animals were not overt, but members of RD207 were significantly more pathogenic, resulting in severe lung damage. The RD207 strains also induced much higher levels of markers associated with regulatory T cells and showed a significant loss of activated T cells in the lungs over the course of the infections. Whole-genome sequencing of the strains revealed mutations specific for RD207 which may explain this difference. Based on these data, we hypothesize that the sublineages of M. tuberculosis are associated with distinct pathological and clinical phenotypes and that these differences influence the transmissibility of particular M. tuberculosis strains in human populations. PMID:22718126

  7. Comparison of Hourly PM2.5 Observations Between Urban and Suburban Areas in Beijing, China

    PubMed Central

    Yao, Ling; Lu, Ning; Yue, Xiafang; Du, Jia; Yang, Cundong

    2015-01-01

    Hourly PM2.5 observations collected at 12 stations over a 1-year period are used to identify variations between urban and suburban areas in Beijing. The data demonstrates a unique monthly variation form, as compared with other major cities. Urban areas suffer higher PM2.5 concentration (about 92 μg/m3) than suburban areas (about 77 μg/m3), and the average PM2.5 concentration in cold season (about 105 μg/m3) is higher than warm season (about 78 μg/m3). Hourly PM2.5 observations exhibit distinct seasonal, diurnal and day-of-week variations. The diurnal variation of PM2.5 is observed with higher concentration at night and lower value at daytime, and the cumulative growth of nighttime (22:00 p.m. in winter) PM2.5 concentration maybe due to the atmospheric stability. Moreover, annual average PM2.5 concentrations are about 18 μg/m3 higher on weekends than weekdays, consistent with driving restrictions on weekdays. Additionally, the nighttime peak in weekdays (21:00 p.m.) is one hour later than weekends (20:00 p.m.) which also shows the evidence of human activity. These observed facts indicate that the variations of PM2.5 concentration between urban and suburban areas in Beijing are influenced by complex meteorological factors and human activities. PMID:26426035

  8. Generation amount prediction and material flow analysis of electronic waste: a case study in Beijing, China.

    PubMed

    Liu, Xianbing; Tanaka, Masaru; Matsui, Yasuhiro

    2006-10-01

    The draft legislation on e-waste prepared by the Chinese national government assigns management responsibility to local governments. It is an urgent task for the municipal government to plan an effective system as soon as possible to divert the e-waste flow from the existing informal e-waste recycling processes. This paper presents a case study implemented in Beijing, the capital city of China, with the purpose of predicting the amount of obsolete equipment for five main kinds of electronic appliances from urban households and to analyse the flow after the end of their useful phase. The amount to be handled was 885,354 units in 2005 and is predicted to double by 2010. Due to consumption growth and the expansion of urbanization it is estimated that the amount will increase to approximate 2,820,000 units by 2020: 70% of the obsolete appliances will be awaiting collection for possible recycling, 7% will be stored at the owner's home for 1 year on average and 4% will be discarded directly and enter the municipal solid waste collecting system. The remaining items will be reused for about 3 years on average after the change of ownership. The results of this study will assist the waste management authorities of Beijing to plan the collecting system and facilities needed for management of e-waste generated in the near future. PMID:17121115

  9. Energy-dominated local carbon emissions in Beijing 2007: inventory and input-output analysis.

    PubMed

    Guo, Shan; Liu, J B; Shao, Ling; Li, J S; An, Y R

    2012-01-01

    For greenhouse gas (GHG) emissions by Beijing economy 2007, a concrete emission inventory covering carbon dioxide (CO(2)), methane (CH(4)), and nitrous oxide (N(2)O) is presented and associated with an input-output analysis to reveal the local GHG embodiment in final demand and trade without regard to imported emissions. The total direct GHG emissions amount to 1.06E + 08 t CO(2)-eq, of which energy-related CO(2) emissions comprise 90.49%, non-energy-related CO(2) emissions 6.35%, CH(4) emissions 2.33%, and N(2)O emissions 0.83%, respectively. In terms of energy-related CO(2) emissions, the largest source is coal with a percentage of 53.08%, followed by coke with 10.75% and kerosene with 8.44%. Sector 26 (Construction Industry) holds the top local emissions embodied in final demand of 1.86E + 07 t CO(2)-eq due to its considerable capital, followed by energy-intensive Sectors 27 (Transport and Storage) and 14 (Smelting and Pressing of Ferrous and Nonferrous Metals). The GHG emissions embodied in Beijing's exports are 4.90E + 07 t CO(2)-eq, accounting for 46.01% of the total emissions embodied in final demand. The sound scientific database totally based on local emissions is an important basis to make effective environment and energy policies for local decision makers. PMID:23193385

  10. Quantitative evaluation of reactive nitrogen emissions with urbanization: a case study in Beijing megacity, China.

    PubMed

    Xian, Chaofan; Ouyang, Zhiyun; Lu, Fei; Xiao, Yang; Li, Yanmin

    2016-09-01

    The rapid increase in anthropogenic nitrogen (N) load in urbanized environment threatens urban sustainability. In this study, we estimated the amount of reactive N (Nr) as an index of N pollution potential caused by human activities, using the megacity of Beijing as a case study. We investigated the temporal changes in Nr emissions in the environment from 2000 to 2012 using a multidisciplinary approach with quantitative evaluation. The Nr emissions presented slightly increasing during study period, and the annual emission was 0.19 Tg N, mainly resulting from fuel combustion. Nevertheless, the Nr output intensity resulting from inhabitants' livelihoods and material production had weakened over the study period. The evaluation results showed that the environmental measures to remove Nr in Beijing were efficient in most years, suggesting that progress in mitigating the growth of the Nr load in this urban environment was significant. Further measures based on N offset are suggested that could help alleviate the environmental pressure resulting from anthropogenic Nr emissions. These could provide theoretical support for the sustainable development of megacities. PMID:27240830

  11. [Chemical Characteristics and Sources of Atmospheric Carbonyls During the 2014 Beijing APEC].

    PubMed

    He, Xiao-lang; Tan, Ji-hua; Guo, Song-jun; Ma, Yong-liang; He, Ke-bin

    2016-03-15

    Pollution characteristic and variation trend of atmospheric carbonyls were investigated in November during the 2014 Beijing APEC. Formaldehyde, acetaldehyde and acetone were the dominant carbonyls, accounting for 82.66% of total carbonyls, and especially, formaldehyde accounted for 40.12% of total carbonyls. Atmospheric concentrations of total carbonyls decreased by around 64.10% after the clean air policy was carried out during the Beijing APEC, and the variation trend of carbonyls showed a similar pattern to those of other pollutants like PM₂.₅ during the APEC. Strong correlations (R² of 0.67-0.98) were observed among formaldehyde, acetaldehyde, acetone and total carbonyls during and after the APEC, indicating that they had similar sources; however, poor correlations (R² of -0.11-0.42 and 0.16-0.94, respectively) were observed before the APEC, implying different emission sources for ambient carbonyls. The calculated ratios of C1/C2, C2/C3 and OC/EC indicated that both vehicles and coal emissions were responsible for atmospheric carbonyls before the APEC, and emissions from coal burning were the major contributor to atmospheric carbonyls during and after the APEC, especially after the APEC. PMID:27337869

  12. Temporal Patterns in Fine Particulate Matter Time Series in Beijing: A Calendar View.

    PubMed

    Liu, Jianzheng; Li, Jie; Li, Weifeng

    2016-01-01

    Extremely high fine particulate matter (PM2.5) concentration has become synonymous to Beijing, the capital of China, posing critical challenges to its sustainable development and leading to major public health concerns. In order to formulate mitigation measures and policies, knowledge on PM2.5 variation patterns should be obtained. While previous studies are limited either because of availability of data, or because of problematic a priori assumptions that PM2.5 concentration follows subjective seasonal, monthly, or weekly patterns, our study aims to reveal the data on a daily basis through visualization rather than imposing subjective periodic patterns upon the data. To achieve this, we conduct two time-series cluster analyses on full-year PM2.5 data in Beijing in 2014, and provide an innovative calendar visualization of PM2.5 measurements throughout the year. Insights from the analysis on temporal variation of PM2.5 concentration show that there are three diurnal patterns and no weekly patterns; seasonal patterns exist but they do not follow a strict temporal division. These findings advance current understanding on temporal patterns in PM2.5 data and offer a different perspective which can help with policy formulation on PM2.5 mitigation. PMID:27561629

  13. Beijing Lunar Declaration 2010: B) Technology and Resources; Infrastructures and Human Aspects; Moon, Space and Society

    NASA Technical Reports Server (NTRS)

    Arvidson, R.; Foing, B. H.; Plescial, J.; Cohen, B.; Blamont, J. E.

    2010-01-01

    We report on the Beijing Lunar Declaration endorsed by the delegates of the Global Lunar Conference/11th ILEWG Conference on Exploration and Utilisation of the Moon, held at Beijing on 30 May- 3 June 2010. Specifically we focus on Part B:Technologies and resources; Infrastructures and human aspects; Moon, Space, Society and Young Explorers. We recommend continued and enhanced development and implementation of sessions about lunar exploration, manned and robotic, at key scientific and engineering meetings. A number of robotic missions to the Moon are now undertaken independently by various nations, with a degree of exchange of information and coordination. That should increase towards real cooperation, still allowing areas of competition for keeping the process active, cost-effective and faster. - Lunar landers, pressurized lunar rover projects as presented from Europe, Asia and America are important steps that can create opportunities for international collaboration, within a coordinated village of robotic precursors and assistants to crew missions. - We have to think about development, modernization of existing navigation capabilities, and provision of lunar positioning, navigation and data relay assets to support future robotic and human exploration. New concepts and new methods for transportation have attracted much attention and are of great potential.

  14. Dietary supplementation patterns of Korean olympic athletes participating in the Beijing 2008 Summer Olympic Games.

    PubMed

    Kim, Jongkyu; Kang, Seung-ki; Jung, Han-sang; Chun, Yoon-suck; Trilk, Jennifer; Jung, Seung Ho

    2011-04-01

    Athletes report frequent use of various dietary supplements (DSs). However, no study has examined DS use and antidoping knowledge in Korean Olympians. The objectives of this study were to obtain information about Korean Olympians' DS use during the training period for the Beijing 2008 Summer Olympic Games and immediately before their Olympic events, to obtain DS-intake reasons and DS providers, and to obtain information on athletes' doping education, knowledge, and educators. Korean Olympians completed 2 questionnaires 1 wk before the opening and within 1 wk after the closing of the Beijing 2008 Summer Olympic Games. Results showed that 79% of male and 82% of female Olympians take more than 1 DS during the training period and that vitamins and Oriental supplements are the 2 top-ranked DSs. Reasons for DS use were to improve recovery ability (66%) and muscle performance (22%), and sources of obtaining DSs were parents (36%) and coaches (35%). Furthermore, 79% of Korean Olympians reported receiving regular education on antidoping regulations from Olympic-sponsored education classes (64%) and coaches (15%). In conclusion, this study was the first to examine DS use and antidoping-related information in Korean Olympians. Because some herbal products contain substances banned by the World Anti-Doping Agency, athletes should be cautious in using mixed Oriental supplements. PMID:21558578

  15. The influence of governmental mitigation measures on contamination characteristics of PM(2.5) in Beijing.

    PubMed

    Chen, Yuan; Schleicher, Nina; Chen, Yizhen; Chai, Fahe; Norra, Stefan

    2014-08-15

    Beijing, the capital of China, has become one of the most air-polluted cities due to its rapid economic growth. Weekly PM2.5 samples-collected continuously from 2007 to 2010-were used to study the contamination characteristics of atmospheric particles and effects of governmental mitigation measures especially since the 2008 Summer Olympic Games. PM2.5 mass concentrations during the sampling period were reduced compared to the previous studies before 2005, although they were still too high in comparison with environmental standards of China and many other countries as well as WHO standards. Results of principle component analysis show that elements of primary anthropogenic origin had an obvious decline while elements mainly from the natural environment kept a relatively stable course. The governmental macro-control measures influenced both anthropogenic and geogenic sources, but they also led to some pollution peaks prior to implementation of the respective measures. Some element concentrations correlated to the restrictiveness of relative measures, especially during different traffic restrictions. The comparison with other countries and international standards shows that there is a long way to go in order to improve air quality in Beijing, and that governmental mitigation measures need to be continued and reinforced. PMID:24887192

  16. The characteristics of Beijing aerosol during two distinct episodes: impacts of biomass burning and fireworks.

    PubMed

    Cheng, Yuan; Engling, Guenter; He, Ke-bin; Duan, Feng-kui; Du, Zhen-yu; Ma, Yong-liang; Liang, Lin-lin; Lu, Zi-feng; Liu, Jiu-meng; Zheng, Mei; Weber, Rodney J

    2014-02-01

    The chemical composition of Beijing aerosol was measured during summer and winter. Two distinct episodes were identified. Water-soluble potassium (K(+)) increased significantly during the firework episode in winter with an episode to non-episode ratio of 4.97, whereas the biomass burning (BB) episode in summer was characterized by high episode to non-episode ratios of levoglucosan (6.38) and K(+) (6.90). The BB and firework episodes had only a minor influence on the water-soluble OC (organic carbon) to OC ratio. Based on separate investigations of episode and non-episode periods, it was found that: (i) sulfate correlated strongly with both relative humidity and nitrate during the typical winter period presumably indicating the importance of the aqueous-phase oxidation of sulfur dioxide by nitrogen dioxide, (ii) oxalate and WSOC during both winter and summer in Beijing were mainly due to secondary formation, and (iii) high humidity can significantly enhance the formation potential of WSOC in winter. PMID:24275313

  17. Contrasting impacts of urban forms on the future thermal environment: example of Beijing metropolitan area

    NASA Astrophysics Data System (ADS)

    Yang, Long; Niyogi, Dev; Tewari, Mukul; Aliaga, Daniel; Chen, Fei; Tian, Fuqiang; Ni, Guangheng

    2016-03-01

    This study investigated impacts of urban forms on the future thermal environment over Beijing, the capital city of China. Beijing is experiencing remarkable urban expansion and is planned to undergo the transformation of urban forms from single-centric (compact-city) to poly-centric city (dispersed-city). Impacts of urban forms on the future thermal environment were compared and evaluated by conducting numerical experiments based on a regional atmospheric model coupled with a single-layer urban canopy model as well as future climate forcing output from a global climate model. Results show that a dispersed city is efficient in reducing mean urban heat island intensity, but produces larger thermal loading and deeper thermal feedback at the regional scale compared to a compact city. Thermal comfort over downtown areas is reduced in compact-city scenario under future climate conditions. Future climate contributes almost 80% of the additional thermal loading over urban areas, with the remaining 20% contributed by urbanization (for both the compact-city and dispersed-city scenarios). The thermal contrast between the two urban forms is dominated by the expected future climate change. This study leads to two complementary conclusions: (i) for developing assessments related to current climate comfort, urban form of the city is important; (ii) for assessing future climate change impacts, the areal coverage of the city and urbanization extent emerges to be more important than the details related to how the urbanization will evolve.

  18. Spatial And Temporal Variations Analysis Of Urban IPM Pollution In Beijing From 2007 To 2009

    NASA Astrophysics Data System (ADS)

    Gong, Zhao-Ning; Zhao, Wen-Ji; Zhao, Wen-Hui; Tao, Shu

    2010-10-01

    Monitoring summer data obtained from 93 air sampling stations in Beijing urban area from 2007 to 2009, the spatial distribution of PM0.3, PM3.0 and PM5.0 concentration and meteorological factors were simulated by using Kriging method. Meanwhile, the different regularity and spatial variability of inhalable particulate matters (IPM) were shown in the experiment. Furthermore, taking the case of data in 2009, the influences of different meteorological factors such as temperature, humidity and wind speed were analyzed and compared. Finally, based on land cover map derived from remote sensing image, research on the relationship of land use types and local IPM concentration has been carried out. The results showed that spherical models with nuggets could fit the variograms of airborne inhalable particulates. In recent years, the level of inhalable particulate pollution in Beijing has fallen substantially, especially in 2008. The main polluted area was centralized at southwest, northwest was weaker. Pollution level in the central city was relatively light, and the spatial relativity between three kinds of airborne inhalable particulate pollutant and their impact factors had spatial heterogeneity. As for the meteorological factors, the relative humidity significantly affected inhalable particulate pollution. Temperature was second, and the weakest factor was wind speed.

  19. Levels of polybrominated diphenyl ethers and hexabromocyclododecane in the atmosphere and tree bark from Beijing, China.

    PubMed

    Hu, Jicheng; Jin, Jun; Wang, Ying; Ma, Zhaohui; Zheng, Wanjing

    2011-06-01

    Air samples in four seasons at one site and tree bark samples from four districts were determined to investigate seasonal variation and regional distribution of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) in Beijing, China. The total concentrations of PBDEs (∑PBDE) and HBCD (∑HBCD) were in the range of 57-470 and 20-1800 pg m(-3) in the atmosphere, respectively. The ∑PBDE and ∑HBCD concentrations were significantly influenced by the total suspended particulate matter in atmosphere. The total concentrations of PBDEs and HBCD in tree bark samples were in the range of 99-3700 and 26-3400 ng g(-1) lipid weight. It was found that regional distribution of PBDEs and HBCD was related to the function of each district. In addition, the study found that weeping willow bark was an ideal atmospheric PBDEs and HBCD passive sampler. Finally, atmospheric levels of BDE-209 and HBCD at tree bark sampling districts were estimated via applying an established bark/air partitioning model, which had been verified by the measured concentrations in tree bark and atmosphere in Beijing. PMID:21546059

  20. Submicron aerosols during the Beijing Asia-Pacific Economic Cooperation conference in 2014

    NASA Astrophysics Data System (ADS)

    Zhang, J. K.; Wang, L. L.; Wang, Y. H.; Wang, Y. S.

    2016-01-01

    Approximately 30%-40% of industrial practices and 50% of vehicles in operation were limited in Beijing and its surroundings regions during the Beijing Asia-Pacific Economic Cooperation (APEC) conference in 2014. Compared with values obtained prior to the APEC conference, the atmospheric concentration of submicron aerosol particles (PM1) decreased from 101 to 36.9 μg m-3, or 63%. Of all the inorganic species and black carbon present, the concentrations of nitrate to the total concentration of PM1 decreased the most in terms of both mass concentration, from 25.5 to 7.1 μg m-3, and relative contribution, from 21% to 14%. In addition, both sulfate and ammonium decreased substantially by 9.5 and 8.5 μg m-3, respectively. Accordingly, the relative contributions of ammonium nitrate and ammonium sulfate to light extinction decreased by 10% and 5%, respectively, as a result of the pollution control measures implemented during that period. In addition, polycyclic aromatic hydrocarbons in vehicle emissions were reduced significantly.

  1. [Preliminary health risk assessment of heavy metals in drinking waters in Beijing].

    PubMed

    Gao, Ji-jun; Zhang, Li-ping; Huang, Sheng-biao; Ma, Mei; Wang, Zi-jian

    2004-03-01

    Concentrations distribution of the Cu, Hg, Cd, As in drinking water in the 8 city districts and 10 counties in Beijing was studied based on a total of 120 random samples. Health risks associated with 4 metals in drinking water were assessed using USEPA health risk assessment model. The results showed that the concentrations of the heavy metals in drinking water in Beijing ranged from 0.81 to 6.96 micrograms.L-1 for Cu, 0.34-0.82 microgram.L-1 for Cd, 0.10-0.74 microgram.L-1 for Hg and 0.19-3.02 micrograms.L-1 for As. Among the health risks caused by the carcinogens in drinking water, the largest risk associated with As should be in Tongzhou County (2.0 x 10(-5).a-1) and that with Cd should be in Changping County (2.3 x 10(-6).a-1), while both were significantly lower than the maximum allowance levels recommended by ICRP(5 x 10(-5).a-1). Among the non-carcinogenic risks in drinking water, the largest risk was the risk associated with Hg, followed by Cu. The non-carcinogenic risks levels ranged from 10(-8) to 10(-9), much lower than the maximum allowance levels recommended by ICRP. PMID:15202233

  2. The Large Scale Machine Learning in an Artificial Society: Prediction of the Ebola Outbreak in Beijing

    PubMed Central

    Zhang, Peng; Chen, Bin; Ma, Liang; Li, Zhen; Song, Zhichao; Duan, Wei; Qiu, Xiaogang

    2015-01-01

    Ebola virus disease (EVD) distinguishes its feature as high infectivity and mortality. Thus, it is urgent for governments to draw up emergency plans against Ebola. However, it is hard to predict the possible epidemic situations in practice. Luckily, in recent years, computational experiments based on artificial society appeared, providing a new approach to study the propagation of EVD and analyze the corresponding interventions. Therefore, the rationality of artificial society is the key to the accuracy and reliability of experiment results. Individuals' behaviors along with travel mode directly affect the propagation among individuals. Firstly, artificial Beijing is reconstructed based on geodemographics and machine learning is involved to optimize individuals' behaviors. Meanwhile, Ebola course model and propagation model are built, according to the parameters in West Africa. Subsequently, propagation mechanism of EVD is analyzed, epidemic scenario is predicted, and corresponding interventions are presented. Finally, by simulating the emergency responses of Chinese government, the conclusion is finally drawn that Ebola is impossible to outbreak in large scale in the city of Beijing. PMID:26457078

  3. [Characterization of Water-soluble Ions in PM₂.₅ of Beijing During 2014 APEC].

    PubMed

    Yang, Dong-yan; Liu, Bao-xian; Zhang, Da-wei; Shi, Ai-jun; Zhou, Jian-nan; Jing, Kuan; Fu, Jia-ming

    2015-12-01

    The mass concentration of PM₂.₅ associated with its online and off-line water-soluble ions were obtained during 2014- 10- 2014-11. Secondary inorganic species NO₃⁻, SO₄²⁻ and NH₄⁺ were the major components of PM₂.₅ during different observation periods. The total concentration of NO₃⁻, SO₄²⁻ and NH₄⁺ was (26.8 ± 22.5) µg · m⁻³, which contributed (41.7 ± 8.5)% to PM₂.₅. The concentration of NO₃⁻ was higher than those of others and contributed most to PM₂.₅. The ions of NO₃⁻, SO₄²⁻ NH₄⁺ and Cl⁻ all showed three different periods during 2014 Beijing APEC, besides the different meteorological condition, the cumulative effect caused by local emissions and regional pollution could also not be ignored. Although the characteristics of water-soluble ions was different during different observation periods, there was no obvious acidification of PM₂.₅ in Beijing at the end of autumn and beginning of winter. PMID:27011964

  4. Trifluoroacetic Acid Level in the Atmosphere of Beijing and Its Relationship with PM2.5

    NASA Astrophysics Data System (ADS)

    Guo, Junyu; Zhang, Jianbo

    2016-04-01

    Atmospheric concentrations of Trifluoroacetic Acid (TFA), one of the main degradation products of HCFC-123, HCFC-124 and HFC-134a, were detected in Beijing, China between 2013 and 2014. By analyzing the 137 atmospheric samples, the results showed that the annual mean atmospheric concentration of TFA was 1459±223 pg•m-3. TFA was mainly distributed in gaseous phase, for the concentration was 1396±225 pg•m-3, while that in particle phase was 62±8 pg•m-3. Considering the frequent occurrence of hazy weather in Beijing, the relationship between TFA and PM2.5 in atmosphere was analyzed. The correlation analysis shows that the proportion of particle phase in atmosphere concentration of TFA and mass concentration of PM2.5 are positively correlated with each other (P<0.001), indicating the particles have an absorption effect on TFA. At the same time, when mass concentration of PM2.5 in atmosphere is high, atmospheric concentration of TFA is relatively low. According to the correlation analysis, mass concentration of PM2.5 and atmospheric concentration of TFA are negatively correlated with each other (P=0.005). The main reason is very likely that particle's extinction for light can be enhanced as particle level rises, which causes TFA precursors photolysis to weaken. The results indicate that PM2.5 has a significant impact on TFA.

  5. The Effects of Weather Factors on Hand, Foot and Mouth Disease in Beijing.

    PubMed

    Dong, Weihua; Li, Xian'en; Yang, Peng; Liao, Hua; Wang, Xiaoli; Wang, Quanyi

    2016-01-01

    The morbidity and mortality of hand, foot and mouth disease (HFMD) are increasing in Beijing, China. Previous studies have indicated an association between incidents of HFMD and weather factors. However, the seasonal influence of these factors on the disease is not yet understood, and their relationship with the enterovirus 71 (EV71) and Coxsackie virus A16 (CV-A16) viruses are not well documented. We analysed 84,502 HFMD cases from 2008 to 2011 in Beijing to explore the seasonal influence of weather factors (average temperature [AT], average relative humidity [ARH], total precipitation [TP] and average wind speed [AWS]) on incidents of HFMD by using a geographically weighted regression (GWR) model. The results indicated that weather factors differ significantly in their influence on HFMD depending on the season. AT had the greatest effect among the four weather factors, and while the influence of AT and AWS was greater in the summer than in the winter, the influence of TP was positive in the summer and negative in the winter. ARH was negatively correlated with HFMD. Also, we observed more EV71-associated cases than CV-A16 but there is no convincing evidence to show significant differences between the influences of the weather factors on EV71 and CV-A16. PMID:26755102

  6. Determination of Trace Elements in Edible Nuts in the Beijing Market by ICP-M.

    PubMed

    Yin, Liang Liang; Tian, Qing; Shao, Xian Zhang; Kong, Xiang Yin; Ji, Yan Qin

    2015-06-01

    Nuts have received increased attention from the public in recent years as important sources of some essential elements, and information on the levels of elements in edible nuts is useful to consumers. Determination of the elemental distributions in nuts is not only necessary in evaluating the total dietary intake of the essential elements, but also useful in detecting heavy metal contamination in food. The aim of this study was to determine the mineral contents in edible nuts, and to assess the food safety of nuts in the Beijing market. Levels of Li, Cr, Mn, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Cd, Cs, Ba, Pb, Th, and U in 11 types of edible nuts and seeds (macadamia nuts, lotus nuts, pistachios, sunflower seeds, pine nuts, almonds, walnuts, chestnuts, hazelnuts, cashews, and ginkgo nuts) as well as raisins were determined by inductively coupled plasma mass spectrometry (ICP-MS). The accuracy of the method was validated using standard reference materials GBW10014 (cabbage) and GBW10016 (tea). Our results provide useful information for evaluating the levels of trace elements in edible nuts in the Beijing market, will be helpful for improving food safety, and will aid in better protecting consumer interests. PMID:26177906

  7. Survey Study on Chinese University Students' Perceptions of the Political Systems of China and the United States: Using as Examples Five Key Universities in Beijing, Including Peking (Beijing) University and Tsinghua (Qinghua) University

    ERIC Educational Resources Information Center

    Shengluo, Chen

    2011-01-01

    Through surveys of students at Beijing University, Qinghua University, and other institutions, this article finds that today, twenty years after the political disturbance in 1989 and despite the long-term and unremitting efforts made by the Chinese government, China's college students still take a better view of the U.S. political system than they…

  8. Spatio-Temporal Distribution Characteristics and Trajectory Similarity Analysis of Tuberculosis in Beijing, China.

    PubMed

    Li, Lan; Xi, Yuliang; Ren, Fu

    2016-03-01

    Tuberculosis (TB) is an infectious disease with one of the highest reported incidences in China. The detection of the spatio-temporal distribution characteristics of TB is indicative of its prevention and control conditions. Trajectory similarity analysis detects variations and loopholes in prevention and provides urban public health officials and related decision makers more information for the allocation of public health resources and the formulation of prioritized health-related policies. This study analysed the spatio-temporal distribution characteristics of TB from 2009 to 2014 by utilizing spatial statistics, spatial autocorrelation analysis, and space-time scan statistics. Spatial statistics measured the TB incidence rate (TB patients per 100,000 residents) at the district level to determine its spatio-temporal distribution and to identify characteristics of change. Spatial autocorrelation analysis was used to detect global and local spatial autocorrelations across the study area. Purely spatial, purely temporal and space-time scan statistics were used to identify purely spatial, purely temporal and spatio-temporal clusters of TB at the district level. The other objective of this study was to compare the trajectory similarities between the incidence rates of TB and new smear-positive (NSP) TB patients in the resident population (NSPRP)/new smear-positive TB patients in the TB patient population (NSPTBP)/retreated smear-positive (RSP) TB patients in the resident population (RSPRP)/retreated smear-positive TB patients in the TB patient population (RSPTBP) to detect variations and loopholes in TB prevention and control among the districts in Beijing. The incidence rates in Beijing exhibited a gradual decrease from 2009 to 2014. Although global spatial autocorrelation was not detected overall across all of the districts of Beijing, individual districts did show evidence of local spatial autocorrelation: Chaoyang and Daxing were Low-Low districts over the six

  9. Spatio-Temporal Distribution Characteristics and Trajectory Similarity Analysis of Tuberculosis in Beijing, China

    PubMed Central

    Li, Lan; Xi, Yuliang; Ren, Fu

    2016-01-01

    Tuberculosis (TB) is an infectious disease with one of the highest reported incidences in China. The detection of the spatio-temporal distribution characteristics of TB is indicative of its prevention and control conditions. Trajectory similarity analysis detects variations and loopholes in prevention and provides urban public health officials and related decision makers more information for the allocation of public health resources and the formulation of prioritized health-related policies. This study analysed the spatio-temporal distribution characteristics of TB from 2009 to 2014 by utilizing spatial statistics, spatial autocorrelation analysis, and space-time scan statistics. Spatial statistics measured the TB incidence rate (TB patients per 100,000 residents) at the district level to determine its spatio-temporal distribution and to identify characteristics of change. Spatial autocorrelation analysis was used to detect global and local spatial autocorrelations across the study area. Purely spatial, purely temporal and space-time scan statistics were used to identify purely spatial, purely temporal and spatio-temporal clusters of TB at the district level. The other objective of this study was to compare the trajectory similarities between the incidence rates of TB and new smear-positive (NSP) TB patients in the resident population (NSPRP)/new smear-positive TB patients in the TB patient population (NSPTBP)/retreated smear-positive (RSP) TB patients in the resident population (RSPRP)/retreated smear-positive TB patients in the TB patient population (RSPTBP) to detect variations and loopholes in TB prevention and control among the districts in Beijing. The incidence rates in Beijing exhibited a gradual decrease from 2009 to 2014. Although global spatial autocorrelation was not detected overall across all of the districts of Beijing, individual districts did show evidence of local spatial autocorrelation: Chaoyang and Daxing were Low-Low districts over the six

  10. [Particle mass concentrations and size distribution during and after the Beijing Olympic Games].

    PubMed

    Liu, Zi-Rui; Sun, Yang; Li, Liang; Wang, Yue-Si

    2011-04-01

    To study the variance characteristics of particle mass and number concentration during and after the Beijing Olympic Games, on-line measurements of particle mass and number concentration were conducted on the rooftop of a two-story building near the 325 m meteorological observation tower in the courtyard of the Institute of Atmospheric Physics during 2008-08-08 - 2008- 10-07 by using TEOM and APS. Sources and transportation of atmospheric particles during the experiment were discussed with surface meteorology data and backward trajectories calculated using HYSPLIT model. It had been found that the average mass concentration of PM2.5-10 and PM2.5 were (23.1 +/- 1.6) microg x m(-3) and (55.5 +/- 7.3) microg x m(-3) during the Olympic time, which were 18.2% and 16.0% lower than non-Olympic time, and 22.3% and 18.0% lower than non-Source control time. In Olympic time, average number concentration of PN2.5-10 and PN0.5-2.5 were (15 +/- 1) cm(-3) and (3138 +/- 567) cm(-3), which were 23.4% and 27.5% lower than non-Olympic time, and 29.5% and 34.3% lower than non-Source control time. According to the correlation analysis result of particle matter and meteorological factors, there were significant linear relationships between wind speed, relative humidity and precipitation of prior day and particle mass and number concentrations, stepwise regression analysis showed that 42% and 53% of the variance in mass and number concentration of fine particle were both accounted for wind speed and relative humility, while 21% and 39% of the variance in mass and number concentration of coarse particle were both accounted for wind speed and precipitation of prior day. For the entire period, 46% of total air masses came from regions south of Beijing like Baoding and Shijiazhuang and were favor to increase both the mass and number concentration of fine particles, whereas air masses transported from the north and near north regions had a great effect on scavenging both fine and coarse

  11. Chemical composition, sources, and aging process of submicron aerosols in Beijing: Contrast between summer and winter

    NASA Astrophysics Data System (ADS)

    Hu, Weiwei; Hu, Min; Hu, Wei; Jimenez, Jose L.; Yuan, Bin; Chen, Wentai; Wang, Ming; Wu, Yusheng; Chen, Chen; Wang, Zhibin; Peng, Jianfei; Zeng, Limin; Shao, Min

    2016-02-01

    To investigate the seasonal characteristics of submicron aerosol (PM1) in Beijing urban areas, a high-resolution time-of-flight aerosol-mass-spectrometer (HR-ToF-AMS) was utilized at an urban site in summer (August to September 2011) and winter (November to December 2010), coupled with multiple state of the art online instruments. The average mass concentrations of PM1 (60-84 µg m-3) and its chemical compositions in different campaigns of Beijing were relatively consistent in recent years. In summer, the daily variations of PM1 mass concentrations were stable and repeatable. Eighty-two percent of the PM1 mass concentration on average was composed of secondary species, where 62% is secondary inorganic aerosol and 20% secondary organic aerosol (SOA). In winter, PM1 mass concentrations changed dramatically because of the different meteorological conditions. The high average fraction (58%) of primary species in PM1 including primary organic aerosol (POA), black carbon, and chloride indicates primary emissions usually played a more important role in the winter. However, aqueous chemistry resulting in efficient secondary formation during occasional periods with high relative humidity may also contribute substantially to haze in winter. Results of past OA source apportionment studies in Beijing show 45-67% of OA in summer and 22-50% of OA in winter can be composed of SOA. Based on the source apportionment results, we found 45% POA in winter and 61% POA in summer are from nonfossil sources, contributed by cooking OA in both seasons and biomass burning OA (BBOA) in winter. Cooking OA, accounting for 13-24% of OA, is an important nonfossil carbon source in all years of Beijing and should not be neglected. The fossil sources of POA include hydrocarbon-like OA from vehicle emissions in both seasons and coal combustion OA (CCOA) in winter. The CCOA and BBOA were the two main contributors (57% of OA) for the highest OA concentrations (>100 µg m-3) in winter. The POA

  12. Seasonal variation of trace gas compounds and PM2.5 observed at an urban supersite in Beijing

    NASA Astrophysics Data System (ADS)

    Wu, Yusheng; Hu, Min; Zeng, Limin; Dong, Huabin; Li, Xin; Lu, Keding; Lu, Sihua; Yang, Yudong; Zhang, Yuanhang

    2016-04-01

    The air pollution in Beijing has been a growing concern in the last ten years. We have performed measurements on trace gas compounds (CO, NOx, NOy, O3, SO2), PM2.5, and meteorological parameters at Beijing urban Atmospheric Environmental Observation Station in the campus of Peking University for more than ten years. The measurement results provide us an opportunity to track the air quality change in downtown Beijing. Here, we present observations during year between 2011 and 2015. The annual averaged concentration of CO, NOx, NOy, O3, SO2, and PM2.5 is 1.2 ± 0.1 ppm, 49.9 ± 5.9 ppb, 54.6 ± 4.7 ppb, 26.1 ± 3.8 ppb, 10.6 ± 2.9 ppb, and 53.4 ± 9.8 μg ṡm‑3, respectively. A clear seasonal variation is identified for all the measured trace gas compounds and PM2.5, CO, NOx, NOy, SO2, and PM2.5 show their maximum in winter and minimum in summer. Whilst O3 shows an inverse pattern. This result indicates that the air pollution in Beijing is characterized by haze in winter but by photochemical smog in summer. The effects of meteorological conditions and emissions on the occurrence of pollution episode are discussed in details based on the long-term observation data set.

  13. Relations of SARS-Related Stressors and Coping to Chinese College Students' Psychological Adjustment during the 2003 Beijing SARS Epidemic

    ERIC Educational Resources Information Center

    Main, Alexandra; Zhou, Qing; Ma, Yue; Luecken, Linda J.; Liu, Xin

    2011-01-01

    This study examined the main and interactive relations of stressors and coping related to severe acute respiratory syndrome (SARS) with Chinese college students' psychological adjustment (psychological symptoms, perceived general health, and life satisfaction) during the 2003 Beijing SARS epidemic. All the constructs were assessed by self-report…

  14. A WebGIS-based system for rainfall-runoff prediction and real-time water resources assessment for Beijing

    NASA Astrophysics Data System (ADS)

    Jia, Yangwen; Zhao, Hongli; Niu, Cunwen; Jiang, Yunzhong; Gan, Hong; Xing, Zhi; Zhao, Xueli; Zhao, Zhixin

    2009-07-01

    A WebGIS-based system designed to predict rainfall-runoff and assess real-time water resources for Beijing was developed to provide support for scientific decision making regarding solving water shortages while effectively reducing urban flood threats in the city. The system adopts a Browse Server (B/S) structure and combines the distributed hydrologic modeling and WebGIS techniques. For this system, a distributed hydrologic model of Beijing that adopts a grid cell-size of 1 km by 1 km and covers the city's entire area of 16,400 km 2 was developed and validated. This model employs a simple, yet practical rainfall-runoff correlation curve method to predict runoff, as well as prediction approaches for rainfall, evaporation, subsurface runoff and recharge to groundwater. In addition, a framework for the assessment of real-time water resources assessment based on hydrologic monitoring stations and the distributed model was established. Finally, a WebGIS-based system for rainfall-runoff prediction and real-time water resources assessment for Beijing was developed by integrating a data platform, the professional models and the WebGIS techniques. This system was successfully integrated into the hydrologic prediction practices of the General Station of Hydrology, Bureau of Beijing Water Affairs in 2005, and the demonstration version of the system can be seen on the Web at http://123.127.143.23/enewRF/login/login.aspx?ReturnUrl=%2fenewRF%2ftemp.aspx.

  15. An Evaluation of Beijing 1995 on the Appointments and Promotions of Nigerian Women to Decision-Making Positions

    ERIC Educational Resources Information Center

    Ifedili, Chika Josephine A.; Ifedili, Chigozie Adaora

    2009-01-01

    The paper assessed the after effect of Beijing women conference of 1995. It looked at issues of women with special regard to the resistance of men to women advancing to higher position; the rate of exposure of rural women to the struggle of women for equal opportunities with men and the attitudes of traditional men and women towards education of…

  16. [Molecular epidemiological characteristics of HIV-1 strains isolated from newly diagnosed MSM subjects (2006-2010) in Beijing, China].

    PubMed

    Ye, Jing-Rong; Zang, Wan-Chun; Su, Xue-Li; Lu, Hong-Yan; Hao, Ming-Qiang; Xin, Ruo-Lei; Chen, Guo-Min; He, Xiong; Zeng, Yi

    2014-03-01

    This study aims to analyze the molecular epidemiological characteristics of HIV-1 strains prevailing among men who have sex with men (MSM) in Beijing, China. The pol gene fragments from 250 newly diagnosed HIV-1-infected MSM individuals during 2006-2010 in Beijing were amplified by RT-nested PCR, sequenced, and phylogenetically analyzed. HIV-1 pol gene from 189 individuals were amplified and analyzed; 81 (42. 9%), 3 (1. 6%), 2 (1.0%), 88 (46. 6%), and 15 (7.9%) individuals were infected with HIV-1 subtypes B, B', C, CRF01_AE, and CRF07_BC, respectively. The subtypes B and CRF01_AE could both be grouped into two clusters, and CRFO7_BC strains shared high homology and were presumed to originate from a common ancestor. The HIV-1 circulating in MSM in Beijing had a lower genetic diversity than in heterosexuals. The HIV-1 epidemic (2006-2010) in MSM in Beijing was actually a rapid spread of HIV-1 CRF01 AE and B, or rather native strains of the two viruses. PMID:24923166

  17. Hygiene Behaviors Associated with Influenza-Like Illness among Adults in Beijing, China: A Large, Population-Based Survey

    PubMed Central

    Wu, Shuangsheng; Ma, Chunna; Yang, Zuyao; Yang, Peng; Chu, Yanhui; Zhang, Haiyan; Li, Hongjun; Hua, Weiyu; Tang, Yaqing; Li, Chao; Wang, Quanyi

    2016-01-01

    The objective of this study was to identify possible hygiene behaviors associated with the incidence of ILI among adults in Beijing. In January 2011, we conducted a multi-stage sampling, cross-sectional survey of adults living in Beijing using self-administered anonymous questionnaires. The main outcome variable was self-reported ILI within the past year. Multivariate logistic regression was used to identify factors associated with self-reported ILI. A total of 13003 participants completed the questionnaires. 6068 (46.7%) of all participants reported ILI during the past year. After adjusting for demographic characteristics, the variables significantly associated with a lower likelihood of reporting ILI were regular physical exercise (OR 0.80; 95% CI 0.74–0.87), optimal hand hygiene (OR 0.87; 95% CI 0.80–0.94), face mask use when going to hospitals (OR 0.87; 95% CI 0.80–0.95), and not sharing of towels and handkerchiefs (OR 0.68; 95% CI 0.63–0.73). These results highlight that personal hygiene behaviors were potential preventive factors against the incidence of ILI among adults in Beijing, and future interventions to improve personal hygiene behaviors are needed in Beijing. PMID:26840614

  18. Problems with Academic Preferences Indicated by Students of Beijing Municipality Taking the Entrance Examination for Colleges and Universities.

    ERIC Educational Resources Information Center

    Jing'an, Zhang

    1987-01-01

    Based on survey data collected in 1982, this article reports the enrollment preferences of students entering colleges and universities in China. Results showed a clear preference for universities whose graduates are to be allocated jobs in Beijing and for the career fields of medicine, computer science, and radio communications. (JDH)

  19. Satellite-based estimates of reduced CO and CO2 emissions due to traffic restrictions during the 2008 Beijing Olympics

    NASA Astrophysics Data System (ADS)

    Worden, Helen M.; Cheng, Yafang; Pfister, Gabriele; Carmichael, Gregory R.; Zhang, Qiang; Streets, David G.; Deeter, Merritt; Edwards, David P.; Gille, John C.; Worden, John R.

    2012-07-01

    During the 2008 Olympics, the Chinese government made a significant effort to improve air quality in Beijing, including restrictions on traffic. Here we estimate the reductions in carbon monoxide (CO) and carbon dioxide (CO2) emissions resulting from the control measures on Beijing transportation. Using MOPITT (Measurements Of Pollution In The Troposphere) multispectral satellite observations of near-surface CO along with WRF-Chem (Weather Research and Forecasting model with Chemistry) simulations for Beijing during August, 2007 and 2008, we estimate changes in CO due to meteorology and transportation sector emissions. Applying a reported CO/CO2 emission ratio for fossil fuels, we find the corresponding reduction in CO2, 60 ± 36 Gg[CO2]/day. As compared to emission scenarios being considered for the IPCC AR5 (Intergovernmental Panel on Climate Change, 5th Assessment Report), this result suggests that urban traffic controls on the Beijing Olympics scale could play a significant role in meeting target reductions for global CO2 emissions.

  20. Chinese Teachers' Perceptions of the Roles and Functions of School Psychological Service Providers in Beijing

    ERIC Educational Resources Information Center

    Wang, Cixin; Ni, Hong; Ding, Yi; Yi, Chunli

    2015-01-01

    This study used a semi-structured interview with 94 teachers from 92 elementary and secondary schools in Beijing, China, to explore their perceptions of the roles, training, and challenges of school psychological service providers (SPs) as well as teachers' satisfaction with the services provided by SPs. Results indicated that the SP to…

  1. Hygiene Behaviors Associated with Influenza-Like Illness among Adults in Beijing, China: A Large, Population-Based Survey.

    PubMed

    Wu, Shuangsheng; Ma, Chunna; Yang, Zuyao; Yang, Peng; Chu, Yanhui; Zhang, Haiyan; Li, Hongjun; Hua, Weiyu; Tang, Yaqing; Li, Chao; Wang, Quanyi

    2016-01-01

    The objective of this study was to identify possible hygiene behaviors associated with the incidence of ILI among adults in Beijing. In January 2011, we conducted a multi-stage sampling, cross-sectional survey of adults living in Beijing using self-administered anonymous questionnaires. The main outcome variable was self-reported ILI within the past year. Multivariate logistic regression was used to identify factors associated with self-reported ILI. A total of 13003 participants completed the questionnaires. 6068 (46.7%) of all participants reported ILI during the past year. After adjusting for demographic characteristics, the variables significantly associated with a lower likelihood of reporting ILI were regular physical exercise (OR 0.80; 95% CI 0.74-0.87), optimal hand hygiene (OR 0.87; 95% CI 0.80-0.94), face mask use when going to hospitals (OR 0.87; 95% CI 0.80-0.95), and not sharing of towels and handkerchiefs (OR 0.68; 95% CI 0.63-0.73). These results highlight that personal hygiene behaviors were potential preventive factors against the incidence of ILI among adults in Beijing, and future interventions to improve personal hygiene behaviors are needed in Beijing. PMID:26840614

  2. Constructing a Theory of Individual Space: Understanding Transnational Migration through the Experience of Return Chinese Immigrants from Canada in Beijing

    ERIC Educational Resources Information Center

    Ding, Yueya

    2015-01-01

    Drawing on life history research, this study critically examines the transnational experiences of return Chinese immigrants from Canada in Beijing. Through the accounts of their experiences, it explores different integration and reintegration strategies, including self-adjustment, lifelong learning and flexible citizenship. A native concept of…

  3. Meta-Synthetic Support Frameworks for Reuse of Government Information Resources on City Travel and Traffic: The Case of Beijing

    ERIC Educational Resources Information Center

    An, Xiaomi; Xu, Shaotong; Mu, Yong; Wang, Wei; Bai, Xian Yang; Dawson, Andy; Han, Hongqi

    2012-01-01

    Purpose: The purpose of this paper is to propose meta-synthetic ideas and knowledge asset management approaches to build a comprehensive strategic framework for Beijing City in China. Design/methodology/approach: Methods include a review of relevant literature in both English and Chinese, case studies of different types of support frameworks in…

  4. The Contributions of School Quality and Teacher Qualifications to Student Performance: Evidence from a Natural Experiment in Beijing Middle Schools

    ERIC Educational Resources Information Center

    Lai, Fang; Sadoulet, Elisabeth; de Janvry, Alain

    2011-01-01

    We use administrative data from the lottery-based open enrollment system in Beijing middle schools to obtain unbiased estimates of school fixed effects on student performance. To do this, we classify children in selection channels, with each channel representing a unique succession of lotteries through which a child was assigned to a school.…

  5. A Survey of Current Pre-School Education of/for Children from Urban Low-Income Families in Beijing

    ERIC Educational Resources Information Center

    Jin-Qinghua; Liu-Yan; Zhang-Yan; Li-Qiong

    2005-01-01

    This study investigated the pre-school education of children from low-income families in six urban districts of Beijing, using questionnaires and in-depth interviews with respondents from district educational committees, sub-district and resident's committees, nursery schools, and low-income families. The results indicated that (1) the number of…

  6. Analysis of urban metabolic processes based on input-output method: model development and a case study for Beijing

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Liu, Hong; Chen, Bin; Zheng, Hongmei; Li, Yating

    2014-06-01

    Discovering ways in which to increase the sustainability of the metabolic processes involved in urbanization has become an urgent task for urban design and management in China. As cities are analogous to living organisms, the disorders of their metabolic processes can be regarded as the cause of "urban disease". Therefore, identification of these causes through metabolic process analysis and ecological element distribution through the urban ecosystem's compartments will be helpful. By using Beijing as an example, we have compiled monetary input-output tables from 1997, 2000, 2002, 2005, and 2007 and calculated the intensities of the embodied ecological elements to compile the corresponding implied physical input-output tables. We then divided Beijing's economy into 32 compartments and analyzed the direct and indirect ecological intensities embodied in the flows of ecological elements through urban metabolic processes. Based on the combination of input-output tables and ecological network analysis, the description of multiple ecological elements transferred among Beijing's industrial compartments and their distribution has been refined. This hybrid approach can provide a more scientific basis for management of urban resource flows. In addition, the data obtained from distribution characteristics of ecological elements may provide a basic data platform for exploring the metabolic mechanism of Beijing.

  7. Effects of DDT and BHC on amino acid content and its varieties in Chlorella vulgaris Beij. and Cladophora sp.

    NASA Astrophysics Data System (ADS)

    Lin, Yixiong

    1991-03-01

    In Chlorella vulgaris Beij. and Cladophora sp. treated with different concentrations of r-BHC and p, p-DDT, the protein and free amino acid content in both were higher than those in the controls, and the free amino acid content was even higher than the protein amino acid content.

  8. Geo-spatial Hotspots of Hemorrhagic Fever with Renal Syndrome and Genetic Characterization of Seoul Variants in Beijing, China

    PubMed Central

    Zuo, Shu-Qing; Fang, Li-Qun; Zhan, Lin; Zhang, Pan-He; Jiang, Jia-Fu; Wang, Li-Ping; Ma, Jia-Qi; Wang, Bing-Cai; Wang, Ri-Min; Wu, Xiao-Ming; Yang, Hong; Cao, Zhi-Wei; Cao, Wu-Chun

    2011-01-01

    Background Hemorrhagic fever with renal syndrome (HFRS) is highly endemic in mainland China, and has extended from rural areas to cities recently. Beijing metropolis is a novel affected region, where the HFRS incidence seems to be diverse from place to place. Methodology/Principal Findings The spatial scan analysis based on geographical information system (GIS) identified three geo-spatial “hotspots” of HFRS in Beijing when the passive surveillance data from 2004 to 2006 were used. The Relative Risk (RR) of the three “hotspots” was 5.45, 3.57 and 3.30, respectively. The Phylogenetic analysis based on entire coding region sequence of S segment and partial L segment sequence of Seoul virus (SEOV) revealed that the SEOV strains circulating in Beijing could be classified into at least three lineages regardless of their host origins. Two potential recombination events that happened in lineage #1 were detected and supported by comparative phylogenetic analysis. The SEOV strains in different lineages and strains with distinct special amino acid substitutions for N protein were partially associated with different spatial clustered areas of HFRS. Conclusion/Significance Hotspots of HFRS were found in Beijing, a novel endemic region, where intervention should be enhanced. Our data suggested that the genetic variation and recombination of SEOV strains was related to the high risk areas of HFRS, which merited further investigation. PMID:21264354

  9. [δ¹⁵N-NO₃⁻ and δ¹⁸O-NO₃⁻ Tracing of Nitrate Sources in Beijing Urban Rivers].

    PubMed

    Zhao, Qing-liang; Ma, Hui-ya; Ren, Yu-fen; Wang, Xiao-ke; Peng, Jian-feng; He, Cheng-wu; Wu, Jun-hang; Liu, Meng-zhen; Yan, Miao-miao

    2016-05-15

    In order to quantitatively identify sources of nitrate pollution in Beijing urban area and provide effective guidance for relevant departments to control the pollution of Beijing rivers, δ¹⁵N-NO₃⁻ and δ¹⁸O-NO₃⁻ isotope tracing method was used to analyze the composition of nitrogen and oxygen stable isotopes from nitrate in Beijing urban river. Besides, stable isotope mixing model was adopted to track nitrogen sources of nitrate in Beijing urban rivers and the contribution rates of respective pollution sources were evaluated. The results showed that: (1) NO₃⁻-N pollution was the main inorganic nitrogen pollution in Beijing rivers and pollution of downstream was more serious than that of upstream. (2) δ¹⁵N-NO₃⁻ in Beijing urban surface rivers was in range of 6.26 per thousand-24.94 per thousand, while δ¹⁸O-NO₃⁻ ranged -0.41 per thousand-11.74 per thousand; δ¹⁵N-NO₃⁻ increased from upstream to downstream along the flow of the surface water. (3) The nitrate pollution composition of Beijing rivers could be gained from the stable isotope mixing model. The average contribution rates of manure and sewage, soil nitrate and atmospheric deposition were 61.2%, 31.5% and 7.3%, respectively. PMID:27506021

  10. Whole genome analysis of an MDR Beijing/W strain of Mycobacterium tuberculosis with large genomic deletions associated with resistance to isoniazid.

    PubMed

    Zhang, Qiufen; Wan, Baoshan; Zhou, Aiping; Ni, Jinjing; Xu, Zhihong; Li, Shuxian; Tao, Jing; Yao, YuFeng

    2016-05-15

    Mycobacterium tuberculosis (M.tb) is one of the most prevalent bacterial pathogens in the world. With geographical wide spread and hypervirulence, Beijing/W family is the most successful M.tb lineage. China is a country of high tuberculosis (TB) and high multiple drug-resistant TB (MDR-TB) burden, and the Beijing/W family strains take the largest share of MDR strains. To study the genetic basis of Beijing/W family strains' virulence and drug resistance, we performed the whole genome sequencing of M.tb strain W146, a clinical Beijing/W genotype MDR isolated from Wuxi, Jiangsu province, China. Compared with genome sequence of M.tb strain H37Rv, we found that strain W146 lacks three large fragments and the missing of furA-katG operon confers isoniazid resistance. Besides the missing of furA-katG operon, strain W146 harbored almost all known drug resistance-associated mutations. Comparison analysis of single nucleotide polymorphisms (SNPs) and indels between strain W146 and Beijing/W genotype strains and non-Beijing/W genotype strains revealed that strain W146 possessed some unique mutations, which may be related to drug resistance, transmission and pathogenicity. These findings will help to understand the large sequence polymorphisms (LSPs) and the transmission and drug resistance related genetic characteristics of the Beijing/W genotype of M.tb. PMID:26854371

  11. Randomized control trial for the assessment of the anti-albuminuric effects of topiroxostat in hyperuricemic patients with diabetic nephropathy (the ETUDE study)

    PubMed Central

    Kato, Sawako; Ando, Masahiko; Mizukoshi, Toshihiro; Nagata, Takanobu; Katsuno, Takayuki; Kosugi, Tomoki; Tsuboi, Naotake; Maruyama, Shoichi

    2016-01-01

    ABSTRACT Proteinuria is an established risk factor for diabetic nephropathy. Recent studies indicate that some xanthine oxidase inhibitors have a renoprotective effect. The aim of this study was to assess whether topiroxostat reduces albuminuria in hyperuricemic patients with diabetic nephropathy and overt proteinuria. The ETUDE study is an ongoing 24-week, multicenter, open-label, randomized (1:1), parallel group study involving hyperuricemic patients with diabetic nephropathy (estimated glomerular filtration rate [eGFR] ≥ 20 mL/min/1.73 m2) and overt proteinuria (0.3 ≤ urine protein to creatinine ratio (UPCR) < 3.5 g/g Cr). Patients are randomly assigned to high dose (topiroxostat 160 mg daily) or low dose (topiroxostat 40 mg daily) on top of standard of care. The primary endpoint is the change in albuminuria indicated by urine albumin-to-creatinine ratio after 24 treated weeks relative to the baseline values. This trial was registered at the Japanese University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR: UMIN 000015403). The background, rationale, and study design of this trial are presented here. Seventy-six patients from four registered facilities have already been enrolled and received at least one dose of topiroxostat. This trial will end in 2017. The ETUDE trial is the first randomized controlled study of topiroxostat in hyperuricemic patients with diabetic nephropathy and overt proteinuria. We will clarify the pleiotropic function of topiroxostat including an anti-albumiuric effect as well as its effects on safely decreasing serum uric acid levels. PMID:27303100

  12. Estimated Reduction in Cancer Risk due to PAH Exposures If Source Control Measures during the 2008 Beijing Olympics Were Sustained

    PubMed Central

    Jia, Yuling; Stone, Dave; Wang, Wentao; Schrlau, Jill; Tao, Shu; Massey Simonich, Staci L.

    2011-01-01

    Background The 2008 Beijing Olympic Games provided a unique case study to investigate the effect of source control measures on the reduction in air pollution, and associated inhalation cancer risk, in a Chinese megacity. Objectives We measured 17 carcinogenic polycyclic aromatic hydrocarbons (PAHs) and estimated the lifetime excess inhalation cancer risk during different periods of the Beijing Olympic Games, to assess the effectiveness of source control measures in reducing PAH-induced inhalation cancer risks. Methods PAH concentrations were measured in samples of particulate matter ≤ 2.5 μm in aerodynamic diameter (PM2.5) collected during the Beijing Olympic Games, and the associated inhalation cancer risks were estimated using a point-estimate approach based on relative potency factors. Results We estimated the number of lifetime excess cancer cases due to exposure to the 17 carcinogenic PAHs [12 priority pollutant PAHs and five high-molecular-weight (302 Da) PAHs (MW 302 PAHs)] to range from 6.5 to 518 per million people for the source control period concentrations and from 12.2 to 964 per million people for the nonsource control period concentrations. This would correspond to a 46% reduction in estimated inhalation cancer risk due to source control measures, if these measures were sustained over time. Benzo[b]fluoranthene, dibenz[a,h]anthracene, benzo[a]pyrene, and dibenzo[a,l]pyrene were the most carcinogenic PAH species evaluated. Total excess inhalation cancer risk would be underestimated by 23% if we did not include the five MW 302 PAHs in the risk calculation. Conclusions Source control measures, such as those imposed during the 2008 Beijing Olympics, can significantly reduce the inhalation cancer risk associated with PAH exposure in Chinese megacities similar to Beijing. MW 302 PAHs are a significant contributor to the estimated overall inhalation cancer risk. PMID:21632310

  13. Origin of non-spherical particles in the boundary layer over Beijing, China: based on balloon-borne observations.

    PubMed

    Chen, Bin; Yamada, Maromu; Iwasaka, Yasunobu; Zhang, Daizhou; Wang, Hong; Wang, Zhenzhu; Lei, Hengchi; Shi, Guangyu

    2015-10-01

    Vertical structures of aerosols from the ground to about 1,000 m altitude in Beijing were measured with a balloon-borne optical particle counter. The results showed that, in hazy days, there were inversions at approximately 500-600 m, below which the particulate matters were well mixed vertically, while the concentration of particles decreased sharply above the mixing layer. Electron microscopic observation of the particles collected with the balloon-borne impactor indicates that the composition of particles is different according to weather conditions in the boundary mixing layer of Beijing city and suggests that dust particles are always dominant in coarse-mode particles. Interestingly, sea-salt particles are frequently identified, suggesting the importance of marine air inflow to the Beijing area even in summer. The Ca-rich spherical particles are also frequently identified, suggesting chemical modification of dust particle by NOx or emission of CaO and others from local emission. Additionally, those types of particles showed higher concentration above the mixing layer under the relatively calm weather condition of summer, suggesting the importance of local-scale convection found in summer which rapidly transported anthropogenic particles above the mixing layer. Lidar extinction profiles qualitatively have good consistency with the balloon-borne measurements. Attenuation effects of laser pulse intensity are frequently observed due to high concentration of particulate matter in the Beijing atmosphere, and therefore quantitative agreement of lidar return and aerosol concentration can be hardly observed during dusty condition. Comparing the depolarization ratio obtained from the lidar measurements with the balloon-borne measurements, the contribution of the dry sea-salt particles, in addition to the dust particles, is suggested as an important factor causing depolarization ratio in the Beijing atmosphere. PMID:25537163

  14. Regional and Local Influences on Surface O3 over Beijing: Constraints from Integrated Surface observations and Modeling

    NASA Astrophysics Data System (ADS)

    Wang, Y.; McElroy, M. B.; Munger, W.; Hao, J.; Ma, H.; Chen, Y.

    2007-05-01

    Beijing, the Chinese capital, faces the challenge of improving its atmospheric environment while seeing an annual growth rate of 15% in the number of personal vehicles on the road. Among many pollutants, surface ozone is of particular concern for Beijing as it will host the "green" Olympics Games in summer 2008. Continuous measurements of surface O3 and CO at Miyun (a rural site 50km northeast of Beijing) in 2006 are analyzed using a 3-dimensional chemical transport model (GEOS-Chem) to improve our understanding of regional and local factors contributing to changes in tropospheric O3 in the Beijing area. The location of the site was selected to sample both clean continental air and pollution included in the plume from Beijing. To our knowledge, this is the first station in mainland China providing continuous measurements of O3 and related species (CO and CO2) over a relatively long period (years). Observations show that O3 peaks in June and September, while CO has a broad maximum in winter. Using updated emissions for China, the model successfully reproduces the seasonal variability in O3, CO, and their correlations observed at Miyun. Regional O3 levels representative of north China are identified from observations using concurrent measurements of CO. Events with daytime peak O3 concentrations exceeding 100 ppb were observed mainly in summer (JJA) and in September. A major discrepancy of the model is an overestimate of O3 in July. Observations show a decrease of 16 ppb in mean (median) O3 from June to July, presumably associated with enhanced precipitation and cloudiness in July. Implications of high levels of O3 for crop production will be discussed.

  15. Transport of gaseous NO2 and SO2 by MAX-DOAS in Beijing and surrounding area

    NASA Astrophysics Data System (ADS)

    Xu, Jin; Li, Ang; Xie, Pinhua; Liu, Jianguo; Liu, Wenqing

    2016-04-01

    With the development of industry and urbanization, regional pollution is increasing seriously, and the cross influence between cities is becoming more frequently. Multi Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) has been successfully applied in the remote sensing of gaseous pollutants during the past decade, it is based on scattered light of the sun, and can measure spectral in different directions, measure tropospheric and the whole atmospheric column densities of trace gases combining with radiative transfer model (RTM). This approach is very useful for the investigation of the main path of air pollution transportation. Fifteen MAX-DOAS stations which are in urban and in the path of pollution transport are set up in Beijing and surrounding area including Tianjin and Hebei province to observe the spatial and temporal distributions and regional transport of gaseous NO2 and SO2. The NO2 VCDs and profiles and SO2 VCDs are obtained. The results show that the NO2 column densities in urban are higher than surroundings, it shows that the NO2 in Beijing is mainly from the local; The SO2 column densities in other cities to the south of Beijing are obviously higher than in Beijing, so regional transport from the south of Hebei province will have a significant impact on Beijing. From the results of NO2 and SO2, the whole pollution process including incubation, generation, duration, and dispersion was observed. The vertical distribution show that NO2 concentration is mainly near the surface from 0 to 400m, and SO2 is higher in the transport process.

  16. Temporal trends and spatial variation characteristics of primary air pollutants emissions from coal-fired industrial boilers in Beijing, China.

    PubMed

    Xue, Yifeng; Tian, Hezhong; Yan, Jing; Zhou, Zhen; Wang, Junling; Nie, Lei; Pan, Tao; Zhou, Junrui; Hua, Shenbing; Wang, Yong; Wu, Xiaoqing

    2016-06-01

    Coal-fired combustion is recognized as a significant anthropogenic source of atmospheric compounds in Beijing, causing heavy air pollution events and associated deterioration in visibility. Obtaining an accurate understanding of the temporal trends and spatial variation characteristics of emissions from coal-fired industrial combustion is essential for predicting air quality changes and evaluating the effectiveness of current control measures. In this study, an integrated emission inventory of primary air pollutants emitted from coal-fired industrial boilers in Beijing is developed for the period of 2007-2013 using a technology-based approach. Future emission trends are projected through 2030 based on current energy-related and emission control policies. Our analysis shows that there is a general downward trend in primary air pollutants emissions because of the implementation of stricter local emission standards and the promotion by the Beijing municipal government of converting from coal-fired industrial boilers to gas-fired boilers. However, the ratio of coal consumed by industrial boilers to total coal consumption has been increasing, raising concerns about the further improvement of air quality in Beijing. Our estimates indicate that the total emissions of PM10, PM2.5, SO2, NOx, CO and VOCs from coal-fired industrial boilers in Beijing in 2013 are approximately 19,242 t, 13,345 t, 26,615 t, 22,965 t, 63,779 t and 1406 t, respectively. Under the current environmental policies and relevant energy savings and emission control plans, it may be possible to reduce NOx and other air pollutant emissions by 94% and 90% by 2030, respectively, if advanced flue gas purification technologies are implemented and coal is replaced with natural gas in the majority of existing boilers. PMID:27023281

  17. Analysis of organic and elemental carbon in heating and non-heating periods in four locations of Beijing.

    PubMed

    Sun, Fengbin; Lun, Xiaoxiu; Liu, Xuhui; Mo, Li; Li, Renna; Zhang, Hongxia; Chen, Jungang; Cao, Yingying; Shi, Fangtian; Yu, Xinxiao

    2016-01-01

    The concentrations of elemental carbon (EC) and organic carbon (OC) in PM2.5 atmospheric aerosol were measured at four different sites in Beijing: Beijing Olympic Forest Park (OF), Jiufeng National Forest Park (JF), Beijing Forestry University campus lawn (G), and roads near the Beijing Forestry University (S). The winter heating period concentrations were 30-45% higher than the spring non-heating period. Possible reasons for this could be the severe convective weather in spring due to the temperate monsoon, deposition of PM2.5 to plants in spring, stable atmospheric conditions in winter, and/or a greater number of sources of carbonaceous aerosols in winter. The proportion of total carbon (i.e. EC + OC) in PM2.5 in Beijing is high. The OC/EC value was 2.45 (OF) and 2.39 (JF) in winter and 1.6 (OF) and 1.43 (JF) in spring. These ratios and the high correlation of OC with EC in the winter samples indicate a strong primary source of OC. Eight carbon fractions from the four different sampling locations were analysed, and the OC1-4 values were found to vary considerably. In winter, the OC1 values from all four sites were higher than the spring values. Although there were differences at each site, the percentages of OC2, OC3, EC1-OP, and EC2 were the largest. Secondary organic carbon (SOC) formed during long-range transport from the emission sources to the monitoring sites, and the increase of OC2 and OC3 concentrations could be associated with SOC. PMID:26101900

  18. Evaluating the air quality impacts of the 2008 Beijing Olympic Games: On-road emission factors and black carbon profiles

    NASA Astrophysics Data System (ADS)

    Wang, Xing; Westerdahl, Dane; Chen, Lung Chi; Wu, Ye; Hao, Jiming; Pan, Xiaochuan; Guo, Xinbiao; Zhang, K. Max

    The aggressive traffic interventions and emission control measures implemented to improve air quality during the 2008 Beijing Olympic Games created a valuable case study to evaluate the effectiveness of these measures on mitigating air pollution and protecting public health. In this paper, we report the results from our field campaign in summer 2008 on the on-road emission factors of carbon monoxide, black carbon (BC) and ultrafine particles (UFP) as well as the ambient BC concentrations. The fleet average emission factors for light-duty gasoline vehicles (LDGV) showed considerable reduction in the Olympic year (2008) compared to the pre-Olympic year (2007). Our measurement of Black Carbon (BC), a primary pollutant, at different elevations at the ambient site suggests consistent decrease in BC concentrations as the height increased near the ground level, which indicates that the nearby ground level sources, probably dominated by traffic, contributed to a large portion of BC concentrations in the lower atmospheric layer in Beijing during summertime. These observations indicate that people living in near ground levels experience higher exposures than those living in higher floors in Beijing. The BC diurnal patterns on days when traffic control were in place during the Olympic Games were compared to those on non-traffic-control days in both 2007 and in 2008. These patterns strongly suggest that diesel trucks are a major source of summertime BC in Beijing. The median BC concentration on Olympic days was 3.7 μg m -3, which was dramatically lower than the value on non-traffic-control days, indicating the effectiveness of traffic control regulations in BC reduction in Beijing.

  19. Volatile organic compounds measured in summer in Beijing and their role in ground-level ozone formation

    NASA Astrophysics Data System (ADS)

    Shao, Min; Lu, Sihua; Liu, Ying; Xie, Xin; Chang, Chichung; Huang, Shan; Chen, Zhongmin

    2009-01-01

    Beijing has long suffered from serious ground-level ozone pollution, and volatile organic compounds (VOCs) play a key role in ozone formation. To understand the chemical speciation of VOCs in Beijing, nonmethane hydrocarbons (NMHCs) and oxygenated VOCs (OVOCs) were measured in summer in Beijing and nearby provinces (VOCs in this work means NMHCs+OVOCs). A variation of VOC mixing ratios and chemical speciation from 2004 to 2006 was observed at an urban site in Beijing. The typical VOC species, e.g., propane, propene, and toluene, had comparable or lower mixing ratios than levels found in other cities that previously hosted the Olympic Games, while the mixing ratios for isoprene were higher. The chemical compositions of VOCs within Beijing were heavily influenced by vehicular emissions and differed from those obtained in Tianjin and Hebei Province. OVOCs were an important component, accounting for 54% and 37% in the VOC mixing ratio in 2005 and 2006, respectively, and about 40% of the OH loss rates. The main reactive VOC compounds were aldehydes and alkenes. By using isoprene chemistry and the ratio of ethylbenzene to mp-xylene, the initial mixing ratios of VOCs were estimated. The VOCs had similar variation patterns to ambient ozone and peroxyacetyl nitrate (PAN) concentrations. The correlation between daily maximum ozone concentrations and initial VOCs revealed that ozone formation was sensitive to VOCs for both urban (Peking University, PKU) and rural (Yufa) sites. A reduction in NOx would lead to a decrease in ozone at Yufa, but would cause increased ozone at the PKU site.

  20. Observation of a Dust Storm during 2015 Spring over Beijing, China

    NASA Astrophysics Data System (ADS)

    Lv, Y.; Li, D.; Li, Z.; Chen, X.; Xu, H.; Liu, Z.; Qie, L.; Zhang, Y.; Li, K.; Ma, Y.

    2015-12-01

    Dust events bring significant impacts on the regional environment, human health and even climate. There are four major dust explosion areas in the world, such as North America, Australia, Central Asia and Middle East. Located in the Central Asia, North China has a severe desertification because of deforestation and excessive population growth. Beijing is at the fork of three dust transmission paths in Chin, which makes it a dust-prone region for a long history especially in spring. Thanks to the improvement of the ecological environment in Mongolia, the number of dust weather in recent years reduced significantly than before. However, as the spring coming earlier for the relatively high temperature, a severe dust weather process happened suddenly on March 28, 2015 following with the long-term hazy weather, which up to the highest intensity in the nearly two years. A set of ground-based observations for this serious dust event were adopted in this paper. The ground-based remote sensing station is equipped with an automatic CIMEL lidar and an AERONET sun-photometer. Aerosol optical depth (AOD) and aerosol size distribution were measured by sun-photometer. AOD of dust reached 2.0 at 532nm, which was much larger than clear days. And there was an obvious trend that coarse mode increases more significantly and quickly than fine mode when a dust storm occurs. At the same time, data provided by the air quality monitoring and analysis platform of China shown that the PM10 concentration was larger than 1000μg/m3 and PM10 made important contribution to the high AQI. Lidar observation clearly shown the dust spread very tall (higher than 1km) when the dust storm occurrence. After the dust dissipating, the planetary boundary layer roughly from 0 to 3km, aerosol has a very widely vertical distribution. The AOD based on sun-photometer were taken as a constraint, 65 sr were retrieved and analyzed. And the extinction coefficients indicated that the dust had been dissipation near

  1. Ocular Axial Length and Its Associations in Chinese: The Beijing Eye Study

    PubMed Central

    Yin, Guo; Wang, Ya Xing; Zheng, Zhi Yun; Yang, Hua; Xu, Liang; Jonas, Jost B.

    2012-01-01

    Purpose To investigate the normative data of ocular axial length and its associations in Chinese. Method The population-based Beijing Eye Study 2011 is a cross-sectional study performed in Greater Beijing. The study included 3468 individuals (1963 (56.6%) women) with a mean age of 64.6±9.8 years (range: 50–93 years). A detailed ophthalmic and medical examination was performed. Axial length was measured by optical low-coherence reflectometry. Results Axial length measurements were available for 3159 (91.1%) study participants. Mean axial length was 23.25±1.14 mm (range: 18.96–30.88 mm). In multivariate analysis, axial length was significantly associated with the systemic parameters of higher age (P<0.001), higher body height (P = 0.003), higher level of education (P<0.001) and urban region of habitation (P<0.001), and with the ocular parameters of thicker central cornea (P = 0.001), higher corneal curvature radius (P<0.001), deeper anterior chamber (P<0.001), thicker lens (P<0.001), more myopic refractive error (P<0.001), larger pupil diameter (P = 0.018), and higher best corrected visual acuity (P<0.001). It was additionally and negatively associated with the lens vault (P<0.001). In highly myopic eyes, axial length was significantly associated with lower level of education (P = 0.008), more myopic refractive error (P<0.001), and lower best corrected visual acuity (P = 0.034). Conclusions Mean ocular axial length in the older adult population of Greater Beijing (23.25±1.14 mm) was similar to the value measured in other urban populations and was higher than in a rural Central Indian population. The association between axial length and older age may potentially be associated with a survival artifact. The association between axial length and body height agrees with the general association between anthropomorphic measures and eye globe size. The association with the level of education and urban region of habitation confirms with previous

  2. Baseline blood levels of manganese, lead, cadmium, copper, and zinc in residents of Beijing suburb

    SciTech Connect

    Zhang, Long-Lian; Lu, Ling; Pan, Ya-Juan; Ding, Chun-Guang; Xu, Da-Yong; Huang, Chuan-Feng; Pan, Xing-Fu; Zheng, Wei

    2015-07-15

    Baseline blood concentrations of metals are important references for monitoring metal exposure in environmental and occupational settings. The purpose of this study was to determine the blood levels of manganese (Mn), copper (Cu), zinc (Zn), lead (Pb), and cadmium (Cd) among the residents (aged 12–60 years old) living in the suburb southwest of Beijing in China and to compare the outcomes with reported values in various developed countries. Blood samples were collected from 648 subjects from March 2009 to February 2010. Metal concentrations in the whole blood were determined by ICP-MS. The geometric means of blood levels of Mn, Cu, Zn, Pb and Cd were 11.4, 802.4, 4665, 42.6, and 0.68 µg/L, respectively. Male subjects had higher blood Pb than the females, while the females had higher blood Mn and Cu than the males. There was no gender difference for blood Cd and Zn. Smokers had higher blood Cu, Zn, and Cd than nonsmokers. There were significant age-related differences in blood levels of all metals studied; subjects in the 17–30 age group had higher blood levels of Mn, Pb, Cu, and Zn, while those in the 46–60 age group had higher Cd than the other age groups. A remarkably lower blood level of Cu and Zn in this population as compared with residents of other developed countries was noticed. Based on the current study, the normal reference ranges for the blood Mn were estimated to be 5.80–25.2 μg/L; for blood Cu, 541–1475 μg/L; for blood Zn, 2349–9492 μg/L; for blood Pb, <100 μg/L; and for blood Cd, <5.30 μg/L in the general population living in Beijing suburbs. - Highlights: • Baseline blood levels of metals in residents of Beijing suburb are investigated. • BMn and BPb in this cohort are higher than those in other developed countries. • Remarkably lower blood levels of Cu and Zn in this Chinese cohort are noticed. • The reference values for blood levels of Mn, Cu, Zn, Pb, and Cd are established.

  3. Relative efficiency and productivity: a preliminary exploration of public hospitals in Beijing, China

    PubMed Central

    2014-01-01

    Background Third-grade hospitals in Beijing have been rapidly developing in capacity and scale for many years. These hospitals receive a large number of patients, and ensuring their efficient operation is crucial in meeting people’s healthcare needs. In this context, a study of their relative efficiency and productivity would be helpful to identify the driving factors and further improve their performance. Methods After a review of literature, the current numbers of open beds and employees were selected as input variables. The number of outpatient and emergency visits and the number of discharged patients were selected as output variables. A total of 12 third-grade Class A general public hospitals in Beijing were selected for a preliminary study. The panel data from 2006–2009 were collected by the National Institute of Hospital Administration, Ministry of Health of P.R. China. Descriptive analysis and data envelopment analysis were used to analyze the data using Stata 10.0 and DEAP(V2.1) software. Results In the 2006–2009 period, descriptive results show that sample hospitals continuously expanded their capacity and scale, with growth rate of total revenue being the highest among all variables. The DEA results show that the average annual growth rate of productivity was 26.7%, and the rates were 47.3%, 21.3% and 13.8% respectively for two consecutive years. The average annual growth rate of technological change was 28.3%, and the rates were 49.4%, 21.5% and 16.4% respectively for two consecutive years. The average annual growth rate of technical efficiency change was -1.3%, and the rates were -1.4%, -0.02% and -2.2% respectively for two consecutive years. Conclusions The sample hospitals in Beijing experienced substantial productivity growth, but annual growth rates were declining. Substantial technological change was the main contributor to the growth. Although some hospitals exhibited improvements in technical efficiency, there was a slight decline in

  4. Subjective well-being of the elderly in Xi Cheng District, Beijing

    PubMed Central

    Li, Shuo; Xie, Zhaohui; Shao, Jun; Xiao, Cunli; Tian, Liang; Zhao, Rongfeng; Gong, Jiakai; Han, Jinxiang; Wang, Yue; Han, Chao; Dang, Liping; Zhang, Yushi; Chen, Bo; Luo, Xiaojing; Guo, Wei

    2012-01-01

    Background In 2010 the Beijing Municipal Government promulgated a policy aimed at improving the quality of life and subjective well-being of elderly residents that included a component focused on mental health. Aim Identify factors associated with subjective well-being in a representative sample of elderly residents of Xi Cheng District in Beijing. Methods This cross-sectional study administered a self-completion survey to a stratified random sample of 2342 residents of Xi Cheng District who were 60 to 80 years of age. The level of well-being was assessed using a validated Chinese version of the Memorial University of Newfoundland Scale of Happiness (MUNSH). Detailed socioeconomic variables were obtained using a questionnaire developed by the authors. Social support, anxiety, and depression were assessed using validated Chinese versions of the Social Support Rating Scale (SSRS), Self-rating Anxiety Scale (SAS), and Self-rating Depression Scale (SDS). Results Among the 2342 respondents, 1616 (69.0%) had a total MUNSH score of 32 or above, indicating a high level of happiness; 423 (18.1%) has a total SSRS score 32 or below, indicating poor social support; 201 (8.6%) had a total SDS score of 53 or above, indicating significant depression; and 126 (5.3%) had a total SAS score of 50 or above, indicating significant anxiety. In the multivariate regression analysis the self-reported level of depression was the most important factor related to well-being. Anxiety, social support, income level, the quality of family relationships, the ability to self-regulate emotions, and regular exercise were also significantly related to well-being; but gender, marital status, age and educational level were not associated with well-being. Conclusion Among elderly urban residents in Beijing, self-reports of poor subjective well-being are closely associated with self-reports of depressive and anxiety symptoms and also associated with social factors such as social support, income level and

  5. The Prevalence of Thyroid Nodules and an Analysis of Related Lifestyle Factors in Beijing Communities

    PubMed Central

    Jiang, Hua; Tian, Yongfeng; Yan, Wenhua; Kong, Yue; Wang, Haibin; Wang, Anping; Dou, Jingtao; Liang, Ping; Mu, Yiming

    2016-01-01

    Thyroid nodules (TNs) have annual increasing trends worldwide, and large-scale investigations on the prevalence of TNs in Beijing communities have not been conducted since the introduction of salt iodization in 1995. We performed a cross-sectional study to determine the prevalence of TNs, their epidemiological characteristics, and their correlation with lifestyle factors. A total of 6324 permanent residents aged 18 years or older (mean age, 52.15 ± 11.58 years) from seven representative communities in Beijing were included in the analyses. Once informed consent was obtained, the subjects were asked to complete questionnaires, a physical examination, and thyroid ultrasound. A total of 3100 cases had TNs. The overall prevalence rate was 49.0%, and the age-standardized prevalence was 40.1%, which increased significantly as age increased (p < 0.001). The prevalence was significantly higher in females compared to males (p < 0.001), and it was significantly higher among female current smokers and former smokers compared to non-smokers (p = 0.007). There was no correlation between alcohol consumption and TNs, and there were no significant differences in the prevalence among different groups of taste preference. The prevalence decreased with an increased frequency of seafood intake (p = 0.015) and with higher literacy levels (p < 0.001). The Cochran–Armitage trend test showed that the prevalence significantly increased with decreased physical labor and exercise intensity (p < 0.001, p = 0.009). Logistic regression analysis showed that age (Odds ratio (OR) = 1.039 (1.034–1.044), p < 0.001), the female sex (OR = 1.789 (1.527–2.097)), Body mass index (BMI) (OR = 1.019 (1.005–1.034)), and current smoking habits (OR = 1.246 (1.046–1.483)) were independent risk factors for TNs. Our findings indicate that there is a high prevalence of TNs in Beijing, with a higher prevalence in females than in males. Moreover, the prevalence increases as age increases. Smoking and BMI

  6. Impacts of climate change on spring flower tourism in Beijing, China

    NASA Astrophysics Data System (ADS)

    Wang, Huanjiong

    2016-04-01

    The beauty of blooming flowers causes spring to be one of the most picturesque and pleasant seasons in which to travel. However, the blooming time of plant species are very sensitive to small changes in climate. Therefore, recent climate change may shift flowering time and, as a result, may affect timing of spring tourism for tourists. In order to prove this assumption, we gathered data of first flowering date and end of flowering date (1963-2014) for 49 common ornamental plants in Beijing, China. In addition, we used the number of messages (2010-2014) posted on Sina Weibo (one of the most popular microblogs sites in China, in use by well over 30% of internet users, with a market penetration similar to the United States' Twitter) to indicate the tourist numbers of five scenic spots in Beijing. These spots are most famous places for seeing spring flowers, including the Summer Palace, Yuyuantan Park, Beijing Botanical Garden, Jingshan Park, Dadu City Wall Relics Park. The results showed that the number of species in flower starts to increase in early spring and peaks in middle spring, and then begins to decrease from late spring. The date when the number of species in flower peaks can be defined as best date of spring flower tourism, because on this day people can see blooming flowers of most plant species. The best date of spring flower tourism varied from March 31 to May 1 among years with a mean of April 20. At above scenic spots characterized by the beauty of blooming flowers, tourist numbers also had a peak value during spring. Furthermore, peak time of tourist numbers derived from Weibo varied among different years and was related to best date of spring flower tour derived from phenological data. This suggests that the time of spring outing for tourists is remarkably attracted by flowering phenology. From 1963 to 2014, the best date of spring flower tour became earlier at a rate of 1.6 days decade-1, but the duration for spring flower tour (defined as width at

  7. The Prevalence of Thyroid Nodules and an Analysis of Related Lifestyle Factors in Beijing Communities.

    PubMed

    Jiang, Hua; Tian, Yongfeng; Yan, Wenhua; Kong, Yue; Wang, Haibin; Wang, Anping; Dou, Jingtao; Liang, Ping; Mu, Yiming

    2016-04-01

    Thyroid nodules (TNs) have annual increasing trends worldwide, and large-scale investigations on the prevalence of TNs in Beijing communities have not been conducted since the introduction of salt iodization in 1995. We performed a cross-sectional study to determine the prevalence of TNs, their epidemiological characteristics, and their correlation with lifestyle factors. A total of 6324 permanent residents aged 18 years or older (mean age, 52.15 ± 11.58 years) from seven representative communities in Beijing were included in the analyses. Once informed consent was obtained, the subjects were asked to complete questionnaires, a physical examination, and thyroid ultrasound. A total of 3100 cases had TNs. The overall prevalence rate was 49.0%, and the age-standardized prevalence was 40.1%, which increased significantly as age increased (p < 0.001). The prevalence was significantly higher in females compared to males (p < 0.001), and it was significantly higher among female current smokers and former smokers compared to non-smokers (p = 0.007). There was no correlation between alcohol consumption and TNs, and there were no significant differences in the prevalence among different groups of taste preference. The prevalence decreased with an increased frequency of seafood intake (p = 0.015) and with higher literacy levels (p < 0.001). The Cochran-Armitage trend test showed that the prevalence significantly increased with decreased physical labor and exercise intensity (p < 0.001, p = 0.009). Logistic regression analysis showed that age (Odds ratio (OR) = 1.039 (1.034-1.044), p < 0.001), the female sex (OR = 1.789 (1.527-2.097)), Body mass index (BMI) (OR = 1.019 (1.005-1.034)), and current smoking habits (OR = 1.246 (1.046-1.483)) were independent risk factors for TNs. Our findings indicate that there is a high prevalence of TNs in Beijing, with a higher prevalence in females than in males. Moreover, the prevalence increases as age increases. Smoking and BMI are

  8. Chemical and strontium isotope characterization of rainwater in Beijing during the 2008 Olympic year

    NASA Astrophysics Data System (ADS)

    Xu, Zhifang; Tang, Yang; Ji, Jianpeng

    2012-04-01

    To improve the air quality during the 2008 Beijing Olympic Games, the Beijing Municipal Government enforced a series of emission control measures. This provided a valuable case study to evaluate the effectiveness of these aggressive measures on mitigating air pollution and improving the atmospheric environment. In this paper, we report the first results of the chemical and Sr isotopic compositions of the rainwater in Beijing during the 2008 Olympic year. The ionic composition of samples show that Ca2 + and NH4+ were the dominant cations, accounting for about 76-97% of the total cations, and that SO42 - and NO3- were the major anions, accounting for 61-91% of the total anions measured. Using Na as the indicator of marine origin and Al as that of terrestrial inputs, the proportions of sea salt and terrestrial elements were estimated from elemental ratios. The calculated results indicate that the major chemical components were mainly of non-sea-salt origin. Good correlation between Ca2 + and Sr2 + (R2 = 0.85) in rainwater samples indicates the potential of Sr as a provenance tracer for Ca. Sr2 + concentrations in rainwater samples ranged from 0.01 to 2.87 μmol l- 1, with 87Sr/86Sr ratios from 0.7092 to 0.7109. All of the samples had a 87Sr/86Sr ratio higher than that of seawater. The 87Sr/86Sr isotopic and elemental ratio systems show that the data set of rainwater was mainly distributed between the seawater end-member (~ 0.70917) and the soil dust end-member (0.7111-0.7115), and the analysis indicate that the effect of anthropogenic inputs could decrease in 2008. Comparisons of the chemical composition of the rainwater in different periods show that all chemical components, except NH4+, had the lowest concentration levels during the Olympic Game period. The VWM concentrations of major ions in the rainwater decreased significantly during the Olympic period by up to 29% for SO42 -, 39% for NO3-, 38% for Ca2 +, 51% for Mg2 +, 57% for K+, and 44% for Na+, compared with

  9. Chemical composition and size distribution of airborne particulate matters in Beijing during the 2008 Olympics

    NASA Astrophysics Data System (ADS)

    Li, Xingru; Wang, Lili; Wang, Yuesi; Wen, Tianxue; Yang, Yongjie; Zhao, Yanan; Wang, Yingfeng

    2012-04-01

    Size-segregated aerosol samples were collected daily in Beijing from 1 Jun. to 20 Sep. during the Beijing Olympic Games in 2008 to investigate aerosol concentrations, particle size distributions, and sources as well as the effects of pollution control measures on the chemical compositions (including Water-soluble ions, trace elements, elemental carbon (EC), and organic carbon (OC)) in aerosols of different sizes. Water-soluble ions, EC, OC, and trace elements accounted for 45.0%, 1.6%, 14.7%, and 11.4% of the total particle mass (PM), respectively. Approximately 56%, 56%, 30%, 71% and 55% of the PM, water-soluble ions, trace elements, EC and OC, respectively, were associated with particles smaller than 2.1 μm. Sulfate, nitrate, and ammonium were the dominant ions, which together accounted for approximately 77% of total water-soluble ions. The crustal elements accounted for the majority of the trace elements present. Different sources showed different mass size distributions. Anthropogenic source compounds, such as sulfate, nitrate, ammonium, OC, EC, and toxic elements, were mainly present in fine mode aerosols, whereas crustal elements, such as Al, Fe, Ca, Mg and Ba, primarily occurred in the coarse mode. SO42- and NH4+ concentrations were strongly correlated (r2 = 0.90, slope = 1.63) in the fine mode, thereby indicating that SO42- was mainly present as (NH4)2SO4; in contrast, a weak correlation between SO42- and NH4+ (r2 = 0.18, slope = 0.54) was observed in the coarse mode, indicating that SO42- was associated with other ions. Similarly, SO42- and NO3- exhibited a stronger correlation in the fine mode than in the coarse mode, indicating that SO42- and NO3- were formed via the same in-cloud processes in fine particles. The OC/EC ratio and the correlations between EC and OC concentrations showed that the sources of carbonaceous species were secondary organic carbon from fine particles and the long-range transport of coarse carbonaceous particles from biomass

  10. Photochemical production of ozone in Beijing during the 2008 Olympic Games

    NASA Astrophysics Data System (ADS)

    Chou, C. C.-K.; Tsai, C.-Y.; Chang, C.-C.; Lin, P.-H.; Liu, S. C.; Zhu, T.

    2011-09-01

    As a part of the CAREBeijing-2008 campaign, observations of O3, oxides of nitrogen (NOx and NOy), CO, and hydrocarbons (NMHCs) were carried out at the air quality observatory of the Peking University in Beijing, China during August 2008, including the period of the 29th Summer Olympic Games. The measurements were compared with those of the CAREBeijing-2006 campaign to evaluate the effectiveness of the air pollution control measures, which were conducted for improving the air quality in Beijing during the Olympics. The results indicate that significant reduction in the emissions of primary air pollutants had been achieved; the monthly averaged mixing ratios of NOx, NOy, CO, and NMHCs decreased by 42.2, 56.5, 27.8, and 49.7 %, respectively. In contrast to the primary pollutants, the averaged mixing ratio of O3 increased by 42.2 %. Nevertheless, it was revealed that the ambient levels of total oxidant (Ox = O3+NO2+1.5 NOz) and NOz were reduced by 21.3 and 77.4 %, respectively. The contradictions between O3 and Ox were further examined in two case studies. Ozone production rates of 30-70 ppbv h-1 and OPEx of ~8 mole mole-1 were observed on a clear-sky day in spite of the reduced levels of precursors. In that case, it was found that the mixing ratio of O3 increased with the increasing NO2/NO ratio, whereas the NOz mixing ratio leveled off when NO2/NO>8. Consequently, the ratio of O3 to NOz increased to above 10, indicating the shift from VOC-sensitive regime to NOx-sensitive regime. However, in the other case, it was found that the O3 production was inhibited significantly due to substantial reduction in the NMHCs. According to the observations, it was suggested that the O3 and/or Ox production rates in Beijing should have been reduced as a result of the reduction in the emissions of precursors during the Olympic period. However, the nighttime O3 levels increased due to a decline in the NO-O3 titration, and the midday O3 peak levels were elevated because of the shift in

  11. Beijing Lightning Network (BLNET) and the observation on preliminary breakdown processes

    NASA Astrophysics Data System (ADS)

    Wang, Yu; Qie, Xiushu; Wang, Dongfang; Liu, Mingyuan; Su, Debin; Wang, Zhichao; Liu, Dongxia; Wu, Zhijun; Sun, Zhuling; Tian, Ye

    2016-05-01

    Beijing Lightning Network (BLNET), a regional multi-frequency-band lightning detection and location network, has been developed for both research and operational purposes. The network consisted of 15 stations in 2014, covering an area of about 100 km × 85 km in Beijing area. In this paper, we present the configuration of the network and the detailed description on the sensors for the first time. The Chan algorithm and Levenberg-Marquardt method are adopted jointly in the lightning location algorithm. The Monte Carlo simulation reveals that the horizontal and the vertical location errors within BLNET coverage are less than 300 m and 600 m, respectively. The comparison of total lightning location results with the corresponding radar reflectivity for a thunderstorm case indicates that BLNET has a good capability to track thunderstorms in the Beijing area. Besides, we examine the electric field waveforms of the preliminary breakdown process (PBP) of 111 - CG flashes, 92 + CG flashes, 22 normal-polarity IC flashes and 22 inverted-polarity IC flashes. Statistics on the time interval between the largest PBP pulse and the corresponding first RS pulse for CG flash (PB-RS interval), the ratio of the largest PBP pulse to the corresponding first RS pulse for CG flash (PB/RS ratio), the pulse width for individual pulse in the PBP train (Tw) and the time interval between successive pulses in the PBP train (Ti) are presented. The 3D location result shows that the PBP of a - CG flash initiates at an altitude of ~ 6 km and propagates downward to ~ 3 km with a vertical speed of 5.9 × 105 m/s. The initial 10 ms of an IC flash is found to start at ~ 7.2 km and develop upward to ~ 10 km. The vertical propagation speed is estimated to be 4.8 × 105 m/s during the first 6 ms. A PBP with relatively clear branched 3D structure is presented and discussed in the end of the paper. The average 3D propagation speed of two branches is estimated to be 2.1 × 106 m/s and 2.6 × 106 m

  12. [Characteristic comparative study of particulate matters in Beijing before and during the Olympics].

    PubMed

    Zhang, Ju; Ouyang, Zhi-Yun; Miao, Hong; Wang, Xiao-Ke; Ren, Yu-Fen; Song, Wen-Zhi

    2013-07-01

    Two city ecosystem research stations were selected for continuous monitoring of atmospheric fine particulate matter (PM2.5) concentration from June to September 2008, when the Beijing Olympic Games was held. The relationship between meteorological factors, artificial control management measures and PM2.5 dynamic characteristics were analyzed. The results showed that the daily average concentration of PM2.5 at RCEES Station, which is near the 5th North Ring, was 0.067 mg x m(-3) during the study period, and the particle concentration during the Olympic Games was 0.060 mg x m(-3), which was decreased by about 26% compared with the content before the Olympic Games (0.081 mg x m(-3)). As for JX Station located in the 2th South Ring, its daily average concentration of PM2.5 was 0.078 mg x m(-3). Similar to RCEES Station, PM2.5 average content during the Olympic Games (0.069 mg x m(-3)) was 27% lower compared with the content before the Olympic Games (0.095 mg x m(-3)). Two peaks could be found when daily distribution of PM2.5 was displayed, one appeared between 08:00 and 10:00 (the average content for RCEES and JX were 0.068 and 0.089 mg x m(-3), respectively), and the other appeared at 20:00-22:00, which could be attributed to traffic emission and road dust pollution, especially the emission from the growing number of cars in rush hours. Meteorological condition during the whole period was typical in summer in Beijing with both high temperature and humidity. Correlation analysis revealed that the concentrations of PM2.5 had a positive correlation with the air temperature (P < 0.01), while it had no significant relationship with wind speed, relative humidity or precipitation (P > 0.05). Our monitoring results suggested that the artificial air pollution control strategies were effective measures for air pollution control during 2008 Beijing Olympic Game. PMID:24027976

  13. Prevalence of Human Papillomavirus Genotypes Among Women With High-Grade Cervical Lesions in Beijing, China.

    PubMed

    Xiao, Meizhu; Xu, Qiuxiang; Li, Hongyan; Gao, Huiqiao; Bie, Yachun; Zhang, Zhenyu

    2016-01-01

    The aim of the study is to investigate the prevalence of high-risk human papillomavirus (hr-HPV) genotypes among Han women with high-grade cervical lesions in Beijing, China.Cervical cell specimens from patients with histopathologically confirmed cervical lesions at 7 hospitals in Beijing were examined with a validated HPV kit for 13 hr-HPV genotypes during the study period. The patients were divided into a low-grade cervical lesions group (cervical intraepithelial neoplasia grade 1, CIN1) and a high-grade cervical lesions group (CIN2+, including cervical intraepithelial neoplasia grade 2, CIN2; cervical intraepithelial neoplasia grade 3, CIN3; squamous cervical cancer, SCC; and adenocarcinoma of the cervix, ACC) based on the histopathology results.A total of 2817 eligible patients were enrolled, including 610 cases identified as CIN1 and 2207 as CIN2+. The hr-HPV positive rates in the CIN1 and CIN2+ groups were 78.2% (477/610) and 93.3% (2060/2207), respectively. The most frequently detected genotypes were HPV16, 58, 52 and18 in the CIN1 group and HPV16, 58, 33, and 52 in the CIN2+ group, in descending order of prevalence. In addition, the prevalence of HPV18 among the patients with ACC was 28.6% (14/49), significantly >7.2% (54/752) prevalence among the SCC patients (P < 0.001). Additionally, significantly more women in the CIN2+ group had multiple infections compared with those in the CIN1 group (38.1% and 24.9%, respectively; P < 0.001). However, as the cervical lesion grade increased, the prevalence of multiple hr-HPV infections gradually deceased to 44.2% in the CIN2 patients, 36.7% in the CIN3 patients, and 35.3% in the cervical cancer (CC) patients, which included SCC and ACC patients. In cases of multiple hr-HPV infections in the CIN2+ group, double infections accounted for ∼76.6%, and HPV16+58, HPV16+52, and HPV16+18 were the most common combinations, in descending order. The most frequent combination for triple infections was HPV16+58+31, with

  14. Cloud condensation nuclei (CCN) from fresh and aged air pollution in the megacity region of Beijing

    NASA Astrophysics Data System (ADS)

    Gunthe, S. S.; Rose, D.; Su, H.; Garland, R. M.; Achtert, P.; Nowak, A.; Wiedensohler, A.; Kuwata, M.; Takegawa, N.; Kondo, Y.; Hu, M.; Shao, M.; Zhu, T.; Andreae, M. O.; Pöschl, U.

    2011-11-01

    Atmospheric aerosol particles serving as cloud condensation nuclei (CCN) are key elements of the hydrological cycle and climate. CCN properties were measured and characterized during the CAREBeijing-2006 campaign at a regional site south of the megacity of Beijing, China. Size-resolved CCN efficiency spectra recorded for a supersaturation range of S=0.07% to 0.86% yielded average activation diameters in the range of 190 nm to 45 nm. The corresponding effective hygroscopicity parameters (κ) exhibited a strong size dependence ranging from ~0.25 in the Aitken size range to ~0.45 in the accumulation size range. The campaign average value (κ =0.3 ± 0.1) was similar to the values observed and modeled for other populated continental regions. The hygroscopicity parameters derived from the CCN measurements were consistent with chemical composition data recorded by an aerosol mass spectrometer (AMS) and thermo-optical measurements of apparent elemental and organic carbon (EC and OC). The CCN hygroscopicity and its size dependence could be parameterized as a function of only AMS based organic and inorganic mass fractions (forg, finorg) using the simple mixing rule κp ≈ 0.1 · forg + 0.7 · finorg. When the measured air masses originated from the north and passed rapidly over the center of Beijing (fresh city pollution), the average particle hygroscopicity was reduced (κ = 0.2 ± 0.1), which is consistent with enhanced mass fractions of organic compounds (~50%) and EC (~30%) in the fine particulate matter (PM1). Moreover, substantial fractions of externally mixed weakly CCN-active particles were observed at low supersaturation (S=0.07%), which can be explained by the presence of freshly emitted soot particles with very low hygroscopicity (κ < 0.1). Particles in stagnant air from the industrialized region south of Beijing (aged regional pollution) were on average larger and more hygroscopic, which is consistent with enhanced mass fractions (~60%) of soluble inorganic

  15. Cloud condensation nuclei (CCN) from fresh and aged air pollution in the megacity region of Beijing

    NASA Astrophysics Data System (ADS)

    Gunthe, S. S.; Rose, D.; Su, H.; Garland, R. M.; Achtert, P.; Nowak, A.; Wiedensohler, A.; Kuwata, M.; Takegawa, N.; Kondo, Y.; Hu, M.; Shao, M.; Zhu, T.; Andreae, M. O.; Pöschl, U.

    2011-03-01

    Atmospheric aerosol particles serving as cloud condensation nuclei (CCN) are key elements of the hydrological cycle and climate. CCN properties were measured and characterized during the CAREBeijing-2006 campaign at a regional site south of the megacity of Beijing, China. Size-resolved CCN efficiency spectra recorded for a supersaturation range of S = 0.07% to 0.86% yielded average activation diameters in the range of 190 nm to 45 nm. The corresponding effective hygroscopicity parameters (κ) exhibited a strong size dependence ranging from ~0.25 in the Aitken size range to ~0.45 in the accumulation size range. The campaign average value (κ = 0.3 ± 0.1) was similar to the values observed and modeled for other populated continental regions. The hygroscopicity parameters derived from the CCN measurements were consistent with chemical composition data recorded by an aerosol mass spectrometer (AMS) and thermo-optical measurements of apparent elemental and organic carbon (ECa and OC). The CCN hygroscopicity and its size dependence could be parameterized as a function of AMS based organic and inorganic mass fractions using the simple mixing rule κ p ≍ 0.1 · forg + 0.7 · finorg. When the measured air masses originated from the north and passed rapidly over the center of Beijing (fresh city pollution), the average particle hygroscopicity was reduced (κ = 0.2 ± 0.1), which is consistent with enhanced mass fractions of organic compounds (~50%) and ECa (~30%) in the fine particulate matter (PM1). Moreover, substantial fractions of externally mixed weakly CCN-active particles were observed at low supersaturation (S = 0.07%), which can be explained by the presence of freshly emitted soot particles with very low hygroscopicity (κ<0.1). Particles in stagnant air from the industrialized region south of Beijing (aged regional pollution) were on average larger and more hygroscopic, which is consistent with enhanced mass fractions (~60%) of soluble inorganic ions (mostly

  16. Dry deposition of particulate matter at an urban forest, wetland and lake surface in Beijing

    NASA Astrophysics Data System (ADS)

    Liu, Jiakai; Zhu, Lijuan; Wang, Huihui; Yang, Yilian; Liu, Jiatong; Qiu, Dongdong; Ma, Wu; Zhang, Zhenming; Liu, Jinglan

    2016-01-01

    The dry deposition of particular matters from atmosphere to ecosystems is an undesirable consequence of this pollution while the deposition process is also influenced by different land use types. In current study, concentration of fine particles, coarse particles and meteorological data were collected during the daytime in an artificial forest, wetland and a water surface in the Beijing Olympic Park. Dry deposition velocity, fluxes and vegetation collection were calculated by different models and the results were compared. The results show: (1) the deposition velocity onto the forest canopy was higher than which onto the wetland and the water surface and the velocity varied in different seasons; (2) the fine particles deposited most in the winter while the coarse particles was in the spring; (3) the vegetation collection rates of fine particles were lower than coarse particles, and the forest collected more PMs than the wetland plants.

  17. Carbon savings resulting from the cooling effect of green areas: a case study in Beijing.

    PubMed

    Lin, Wenqi; Wu, Tinghai; Zhang, Chengguo; Yu, Ting

    2011-01-01

    Green areas cool the climate of a city, reduce the energy consumption caused by the urban heat island (UHI) effect, and bring along carbon savings. However, the calculation of carbon savings due to the cooling effect of green areas is still not well understood. We have used a Landsat Enhanced Thematic Mapper Plus (ETM+) image of Beijing, to identify the cooled areas, compute the possible energy used to maintain the temperature differences between cooled areas and their surrounding heated areas, and calculate the carbon savings owing to the avoidance of energy use. Results show that a total amount of 14315.37 tons carbon savings was achieved in the study area and the amount was related to the biomass, the size and the shape of green areas. These results demonstrate the importance of carbon savings resulting from green areas' cooling effect. PMID:21444136

  18. Evolutionary history and global spread of the Mycobacterium tuberculosis Beijing lineage.

    PubMed

    Merker, Matthias; Blin, Camille; Mona, Stefano; Duforet-Frebourg, Nicolas; Lecher, Sophie; Willery, Eve; Blum, Michael G B; Rüsch-Gerdes, Sabine; Mokrousov, Igor; Aleksic, Eman; Allix-Béguec, Caroline; Antierens, Annick; Augustynowicz-Kopeć, Ewa; Ballif, Marie; Barletta, Francesca; Beck, Hans Peter; Barry, Clifton E; Bonnet, Maryline; Borroni, Emanuele; Campos-Herrero, Isolina; Cirillo, Daniela; Cox, Helen; Crowe, Suzanne; Crudu, Valeriu; Diel, Roland; Drobniewski, Francis; Fauville-Dufaux, Maryse; Gagneux, Sébastien; Ghebremichael, Solomon; Hanekom, Madeleine; Hoffner, Sven; Jiao, Wei-wei; Kalon, Stobdan; Kohl, Thomas A; Kontsevaya, Irina; Lillebæk, Troels; Maeda, Shinji; Nikolayevskyy, Vladyslav; Rasmussen, Michael; Rastogi, Nalin; Samper, Sofia; Sanchez-Padilla, Elisabeth; Savic, Branislava; Shamputa, Isdore Chola; Shen, Adong; Sng, Li-Hwei; Stakenas, Petras; Toit, Kadri; Varaine, Francis; Vukovic, Dragana; Wahl, Céline; Warren, Robin; Supply, Philip; Niemann, Stefan; Wirth, Thierry

    2015-03-01

    Mycobacterium tuberculosis strains of the Beijing lineage are globally distributed and are associated with the massive spread of multidrug-resistant (MDR) tuberculosis in Eurasia. Here we reconstructed the biogeographical structure and evolutionary history of this lineage by genetic analysis of 4,987 isolates from 99 countries and whole-genome sequencing of 110 representative isolates. We show that this lineage initially originated in the Far East, from where it radiated worldwide in several waves. We detected successive increases in population size for this pathogen over the last 200 years, practically coinciding with the Industrial Revolution, the First World War and HIV epidemics. Two MDR clones of this lineage started to spread throughout central Asia and Russia concomitantly with the collapse of the public health system in the former Soviet Union. Mutations identified in genes putatively under positive selection and associated with virulence might have favored the expansion of the most successful branches of the lineage. PMID:25599400

  19. The beam diagnostic instruments in Beijing radioactive ion-beam facilities isotope separator on-line

    SciTech Connect

    Ma, Y. Cui, B.; Ma, R.; Tang, B.; Chen, L.; Huang, Q.; Jiang, W.

    2014-02-15

    The beam diagnostic instruments for Beijing Radioactive Ion-beam Facilities Isotope Separator On-Line are introduced [B. Q. Cui, Z. H. Peng, Y. J. Ma, R. G. Ma, B. Tang, T. Zhang, and W. S. Jiang, Nucl. Instrum. Methods 266, 4113 (2008); T. J. Zhang, X. L. Guan, and B. Q. Cui, in Proceedings of APAC 2004, Gyeongju, Korea, 2004, http://www.jacow.org , p. 267]. For low intensity ion beam [30–300 keV/1 pA–10 μA], the beam profile monitor, the emittance measurement unit, and the analyzing slit will be installed. For the primary proton beam [100 MeV/200 μA], the beam profile scanner will be installed. For identification of the nuclide, a beam identification unit will be installed. The details of prototype of the beam diagnostic units and some experiment results will be described in this article.

  20. Spatial pattern of heavy metals accumulation risk in urban soils of Beijing and its influencing factors.

    PubMed

    Liu, Rui; Wang, Meie; Chen, Weiping; Peng, Chi

    2016-03-01

    Accumulations of heavy metals in urban soils are highly spatial heterogeneity and affected by multiple factors including soil properties, land use and pattern, population and climatic conditions. We studied accumulation risks of Cd, Cu, Pb and Zn in unban soils of Beijing and their influencing based on the regression tree analysis and a GIS-based overlay model. Result shows that Zinc causes the most extensive soil pollution and Cu result in the most acute soil pollution. The soil's organic carbon content and CEC and population growth are the most significant factors affecting heavy metal accumulation. Other influence factors in land use pattern, urban landscape, and wind speed also contributed, but less pronounced. The soils in areas with higher degree of urbanization and surrounded by intense vehicular traffics have higher accumulation risk of Cd, Cu, Pb, and Zn. PMID:26716731

  1. Characterization of new particle and secondary aerosol formation during summertime in Beijing, China

    NASA Astrophysics Data System (ADS)

    Zhang, Y. M.; Zhang, X. Y.; Sun, J. Y.; Lin, W. L.; Gong, S. L.; Shen, X. J.; Yang, S.

    2011-07-01

    Size-resolved aerosol number and mass concentrations and the mixing ratios of O3 and various trace gases were continuously measured at an urban station before and during the Beijing Olympic and Paralympic Games (5 June to 22 September, 2008). 23 new particle formation (NPF) events were identified; these usually were associated with changes in wind direction and/or rising concentrations of gas-phase precursors or after precipitation events. Most of the NPF events started in the morning and continued to noon as particles in the nucleation mode grew into the Aitken mode. From noon to midnight, the aerosols grew into the accumulation mode through condensation and coagulation. Ozone showed a gradual rise starting around 10:00 local time, reached its peak around 15:00 and then declined as the organics increased. The dominant new particle species were organics (40-75% of PM1) and sulphate; nitrate and ammonium were more minor contributors.

  2. Basic Graduate Curricula of GIS Design in Beijing Normal University, China

    NASA Astrophysics Data System (ADS)

    Liu, H.

    2015-05-01

    As the basic course of postgraduate programme in Beijing Normal University, the Introduction of GIS&T is selected by almost all the students of the GIS specialty and other related specialties like physical and human geography, ecology, environmental science and so on. The number of the students dropped in the course was over 100 each year in the past 5 years. The background of education and demands of the students were very different. How to design the course of Introduction of GIS&T to meet the demands of students is important. This paper include following parts: (1) The analysis of student's difference and the structure design of the course, (2) Spatial thinking and the body of knowledge design, (3) The practice exercises design, and (4) Feedback and evaluating.

  3. Multilayer-based soft X-ray polarimeter at the Beijing Synchrotron Radiation Facility

    NASA Astrophysics Data System (ADS)

    Sun, Li-Juan; Cui, Ming-Qi; Zhu, Jie; Zhao, Yi-Dong; Zheng, Lei; Wang, Zhan-Shan; Zhu, Jing-Tao

    2013-07-01

    A compact high precision eight-axis automatism and two-axis manual soft-ray polarimeter with a multilayer has been designed, constructed, and installed in 3W1B at the Beijing Synchrotron Radiation Facility (BSRF). Four operational modes in the same device, which are double-reflection, double-transmission, front-reflection-behind-transmission and front-transmission-behind-reflection, have been realized. It can be used for the polarization analysis of synchrotron radiation. It also can be used to characterize the polarization properties of the optical elements in the soft X-ray energy range. Some experiments with Mo/Si and Cr/C multilayers have been performed by using this polarimeter with good results obtained.

  4. Radiative forcing of SO2 and NOx: A case study in Beijing

    NASA Astrophysics Data System (ADS)

    Sun, Z. A.; Wang, X. Y.; Zeng, X. N.

    2006-03-01

    A case study was performed in Beijing in 2000 to observe concentrations Of SO2 and NO, in the atmosphere and to evaluate their radiative impact. It was found that the concentrations of these gases are usually high in the morning due to a temperature inversion in the boundary layer. The average concentrations obtained from the observations are much higher than those used in the McClatchey reference atmosphere. The radiative impacts of these gases are calculated using a line-by-line radiative transfer model. The results show that the radiative forcing at the surface due to SO2 is 0.0576 W m(-2) and that due to NOx is 0.0032 W m(-2). These figures are almost compatible with that due to CFC11.

  5. Estimation of carbon dioxide flux and source partitioning over Beijing, China.

    PubMed

    Song, Tao; Wang, Yuesi; Sun, Yang

    2013-12-01

    The magnitude and partitioning of carbon dioxide emission from the urban area in Beijing, China was estimated based on a statistical approach. Results showed that the urban surface is a net source of CO2 to atmosphere. The main sources of CO2 are vehicles, which accounted for 75.5% and 38.9% of CO2 emission in summer and winter, respectively. At midday in summer, the CO2 uptake of -0.034 mg/(m2 x sec) indicated that vegetation is an important sink of CO2 in summer. Comparison between the annual emission rates of CO2 from the statistical approach and that directly measured by the eddy covariance technique implies that a bottom-up emission approach is a viable means to estimate CO2 emission in an urban area. PMID:24649674

  6. Springtime precipitation effects on the abundance of fluorescent biological aerosol particles and HULIS in Beijing

    NASA Astrophysics Data System (ADS)

    Yue, Siyao; Ren, Hong; Fan, Songyun; Sun, Yele; Wang, Zifa; Fu, Pingqing

    2016-07-01

    Bioaerosols and humic-like substances (HULIS) are important components of atmospheric aerosols, which can affect regional climate by acting as cloud condensation nuclei and some of which can damage human health. Up to date, release of bioaerosols and HULIS initiated by precipitation is still poorly understood. Here we present different release processes for bioaerosols, non-bioaerosols and HULIS during a precipitation event in Beijing, China. Large fungal-spore-like aerosols were emitted at the onset and later weak stage of precipitation, the number concentration of which increased by more than two folds, while the number concentration of bacteria-like particles doubled when the precipitation strengthened. Besides, a good correlation between protein-like substances that were measured simultaneously by on-line and off-line fluorescence techniques consolidated their applications to measure bioaerosols. Furthermore, our EEM results suggest that the relative contribution of water-soluble HULIS to microbial materials was enhanced gradually by the rain event.

  7. Risk assessment and water safety plan: case study in Beijing, China.

    PubMed

    Ye, Bixiong; Chen, Yuansheng; Li, Yonghua; Li, Hairong; Yang, Linsheng; Wang, Wuyi

    2015-06-01

    Two typical rural water utilities in Beijing, China were chosen to describe the principles and applications of water safety plans (WSP), to provide a methodological guide for the actual application and improve the quality of rural drinking water quality, and to establish an appropriate method for WSP applied in rural water supply. Hazards and hazardous events were identified and risk assessment was conducted for rural water supply systems. A total of 13 and 12 operational limits were defined for two utilities, respectively. The main risk factors that affect the water safety were identified in water sources, water processes, water disinfection systems and water utility management. The main control measures were strengthening the water source protection, monitoring the water treatment processes, establishing emergency mechanisms, improving chemical input and operating system management. WSP can be feasibly applied to the management of a rural water supply. PMID:26042982

  8. Beijing fifteen years on: the persistence of barriers to gender mainstreaming in health policy.

    PubMed

    Payne, Sarah

    2011-01-01

    In 2010, fifteen years after the Beijing declaration on women's rights, the UN Commission on the Status of Women met to review progress in gender mainstreaming. Reports on gender equality by member states revealed differences in the degree of change achieved in this period, while highlighting common barriers to gender mainstreaming. The same barriers have long been identified by academics and activists, but prove remarkably resistant to strategies to address gender inequalities. This paper reviews approaches to gender mainstreaming in the context of health policy, and suggests that a model of the obstacles to gender mainstreaming, which identifies barriers as essentially pragmatic, conceptual, or political in origin, might enable a more explicit discussion of the factors underlying this resistance and the ways in which they might be challenged. PMID:22292172

  9. When politics froze fashion: the effect of the Cultural Revolution on naming in Beijing.

    PubMed

    Obukhova, Elena; Zuckerman, Ezra W; Zhang, Jiayin

    2014-09-01

    The authors examine the popularity of boys' given names in Beijing before and after the onset of the Cultural Revolution to clarify how exogenous and endogenous factors interact to shape fashion. Whereas recent work in the sociology of culture emphasizes the importance of endogenous processes in explaining fashion, their analysis demonstrates two ways in which politics shaped cultural expression during the Cultural Revolution: by promoting forms of expression reflecting prevailing political ideology and by limiting individuals' willingness to act differently. As argued by Lieberson and developed further in this article, the second condition is important because endogenous fashion cycles require a critical mass of individuals who seek to differentiate themselves from common practice. Exogenous factors can influence the operation of the endogenous factors. The authors discuss the implications of their study for understanding the nature of conformity under authoritarian regimes and social conditions supporting individual expression. PMID:25811071

  10. Student Reflections on a Study Abroad Course to the 2008 Summer Olympics in Beijing

    PubMed Central

    NAVALTA, JAMES W.; LYONS, SCOTT; GIBSON, FRED W.

    2008-01-01

    The authors lead a study abroad trip to Beijing, China during the 2008 Summer Olympic Games. Included are reflections from the students who participated. Throughout the visit, students had the opportunity to complete learning outside of the traditional classroom setting. In addition, various challenges were faced and overcome which also constituted a learning experience and was the cause of reflection. The country of China and all of its historical landmarks had a great impression on these students, especially the day that was spent at the Great Wall. Finally, being able to be at the Olympic Games was a life-changing experience, from the Opening Ceremony to the events that were attended. In all, it was a thoroughly worthwhile adventure and one that we hope to replicate every two years. PMID:27182303

  11. [Evaluation of resource exploitation value and ecosystem service loss in Mentougou District of Beijing City].

    PubMed

    Liu, Xu-Sheng; Li, Feng; Zhao, Dan; Wang, Bei-Bei

    2009-06-01

    By using the evaluation approach of ecosystem services (including market value, opportunity cost, restoration cost, and shadow project approaches), and combining with situation investigation, the ecosystem service loss in Mentougou District of Beijing City caused by coal resource exploitation in 1949-2006 was systematically evaluated. In the study area, coal mining mainly induced the cost increase of solid waste disposal and sink reclamation, and the losses in food production, water self-preserving, residents moving, and water and soil resources. The ecosystem service loss caused by the coal mining in 1949-2006 was about 54.3 billion Yuan RMB, approximately 9 times high of its market economic benefit (5.9 billion Yuan RMB). It was very difficult or needed a long time to restore the damaged ecosystem. PMID:19795655

  12. Beijing and beyond: women's health and gender-based analysis in Canada.

    PubMed

    Hankivsky, Olena

    2006-01-01

    On the tenth anniversary of the Fourth World Conference on Women, held in Beijing, this article evaluates Canada's progress in the area of women's health by critically examining the Women's Health Strategy. Introduced in 1999 by Health Canada, the Strategy is considered Canada's key response to its international commitments for promoting women's health and in particular for implementing a gender-based analysis in all programs, services, policies, and research. By reviewing each objective of the Strategy, the article illustrates the limited progress that has been made to date. It provides arguments for why and how all levels of government should work to improve their response to women's health in Canada and, specifically, how the Women's Health Strategy can be redesigned to be more effective in attending to the needs and concerns of all Canadian women. PMID:16878398

  13. [Atmospheric HCHO gradient monitoring and analysis in Beijing City with a scanning DOAS system].

    PubMed

    Wang, Man-hua; Xie, Pin-hua; Qin, Min; Dou, Ke; Wang, Jie; Li, Ang; Xu, Jin; Shi, Peng; Wu, Feng-cheng

    2011-03-01

    Scanning differential optical absorption spectroscopy (DOAS) technique combined with meteorological tower was used for monitoring vertical profiles of SO2, NO2, O3, HCHO and HONO along three light paths in Beijing City during July 28, 2009 to August 13, 2009. As a result, the time series of concentrations and vertical gradient of HCHO as well as other gases were acquired. By analyzing the vertical distribution frequency characteristics of HCHO, data of other gases and meteorological data, it was concluded that the main source of HCHO is vehicles emissions around the measurement site. The photochemical reaction as the secondary source accounts for a significant proportion of the source of HCHO at certain times of day (around noon, for a few hours). PMID:21595241

  14. [Monitoring and analysis of air pollutants using DOAS in winter of Beijing].

    PubMed

    Zhu, Yan-wu; Fu, Qiang; Xie, Pin-hua; Liu, Wen-qing; Peng, Fu-min; Qin, Min; Lin, Yi-hui; Si, Fu-qi; Dou, Ke

    2009-05-01

    Based on the differential optical absorption spectroscopy (DOAS) technology, the measurement of air pollutants (SOz, NO2, HONO and HCHO) was performed continuously from Jan 19, 2007 to Feb 8, 2007 in Peking University campus. The typical diurnal variation characteristic of SO2 concentration, the main source and the meteorological factors that influence the pollutants were analyzed. The results indicated that the typical diurnal variation of SO2 concentration has the same shape as the letter "V" when wind speed was low, and in the afternoon the SO2 concentration was the lowest, while in other time it was high. Coal-burning made prominent contribution to the concentration of atmospheric various pollutants in the heating period of Beijing. Wind speed played a leading role and other meteorological factors also have some effect, which resulted from the influence of the meteorology on diffusion, transmission, elimination of air pollutants. PMID:19650497

  15. [Monitoring and analysis of vertical profile of atmospheric HONO, NO2 in boundary layer of Beijing].

    PubMed

    Zhu, Yan-Wu; Liu, Wen-Qing; Fang, Jing; Xie, Pin-Hua; Dou, Ke; Qin, Min; Si, Fu-Qi

    2011-04-01

    Based on the scanning differential optical absorption spectroscopy (DOAS) system, field measurement of vertical profiles of HONO and NO2 was performed continuously from Aug. 27, 2007 to Sep. 4, 2007 in Chaoyang District of Beijing, and their vertical profiles were analyzed. Based on the acquired data, the typical vertical variation characteristics of HONO, NO2 and the ratio HONO/NO2 were discussed, and the possible formation sources of HONO were studied. The results indicated that the decrease of HONO with height was faster than the decrease of NO2. The study found good correlation between NO2 and HONO, as well as between the ratio HONO/NO2 and vapor, respectively. Therefore, the authors' conclusion is that HONO was formed by heterogeneous conversion of NO2 on surfaces or near ground and then transported to higher altitudes. PMID:21714264

  16. Temporal variation of trace compound emission on the working surface of a landfill in Beijing, China

    NASA Astrophysics Data System (ADS)

    Duan, Zhenhan; Lu, Wenjing; Li, Dong; Wang, Hongtao

    2014-05-01

    The temporal variation of trace component emissions from the working surface of a landfill in Beijing was investigated. Specific days in a year were selected as representatives for all four seasons. Different chemical species were quantified in all four seasons with the following average concentrations: spring: 41 compounds, 2482.6 μg m-3; summer: 59 compounds, 4512.6 μg m-3; fall: 66 compounds, 2438.4 μg m-3; and winter: 54 compounds, 2901 μg m-3. The detected compounds included sulfur compounds, oxygenated compounds, aromatics, hydrocarbons, halogenated compounds, and terpenes. Oxygenated compounds were the most abundant compound in most samples. Isobutane, ethyl alcohol, limonene, butane, toluene, and trichlorofluoromethane were recognized as the most abundant compounds on the working surface throughout the year. This study would bring new light in assessing the particle pollution in urban areas and the effect of trace components on landfill odor.

  17. Health benefit evaluation of the energy use scenarios in Beijing, China.

    PubMed

    Pan, Xiaochuan; Yue, Wei; He, Kebin; Tong, Shilu

    2007-03-15

    Air pollution is one of the important causal factors for excess cardiorespiratory deaths and diseases. However, little information is available on health gains from clean energy usage in developing countries. In this study the expected population exposed to air pollutants was estimated under the different energy use scenarios by the year 2010, 2020 and 2030, respectively, in the urban area of Beijing, China. The concentration-response functions between air pollutants and the health endpoints were established using meta-analysis and regression models. The decreased cardiorespiratory deaths and diseases of the exposed population were predicted as the health benefits from air pollution reduction. We used daily measurements of particulate matter less than 10 mum in aerodynamic diameter (PM(10)) and sulphate dioxide (SO(2)) as air pollution indicators. The percentage of population exposed to higher level of PM(10) will be decreased significantly under the clean energy use scenario than that under the Baseline Scenario (i.e., business-as-usual scenario). Compared with the Baseline Scenario there will be, by 2010, 2020, and 2030, respectively, a decrease of 29-152, 30-212 and 39-287 acute excess deaths; and 340-1811, 356-2529 and 462-3424 chronic excess deaths associated with the reduction of PM(10) level; also a decrease of 237-331, 285-371 and 400-554 short-term excess deaths associated with the decrease of SO(2) level. Meanwhile, the number of respiratory and cardiovascular hospital admissions, outpatient visits to internal and paediatrics departments, total emergency room visits and asthma attacks will be remarkably reduced with the reduction of air pollution. Energy structure improvement could reduce ambient air pollution and produce substantial health benefits to the population in Beijing. These findings may have significant implications for other metropolitan cities, particularly in developing countries. PMID:17289123

  18. [Emission Characteristics of Water-Soluble Ions in Fumes of Coal Fired Boilers in Beijing].

    PubMed

    Hu, Yue-qi; Ma, Zhao-hui; Feng, Ya-jun; Wang, Chen; Chen, Yuan-yuan; He, Ming

    2015-06-01

    Selecting coal fired boilers with typical flue gas desulfurization and dust extraction systems in Beijing as the study objects, the issues and characteristics of the water-soluble ions in fumes of coal fired boilers and theirs influence factors were analyzed and evaluated. The maximum mass concentration of total water-soluble ions in fumes of coal fired boilers in Beijing was 51.240 mg x m(-3) in the benchmark fume oxygen content, the minimum was 7.186 mg x m(-3), and the issues of the water-soluble ions were uncorrelated with the fume moisture content. SO4(2-) was the primary characteristic water-soluble ion for desulfurization reaction, and the rate of contribution of SO4(2-) in total water-soluble ions ranged from 63.8% to 81.0%. F- was another characteristic water-soluble ion in fumes of thermal power plant, and the rate of contribution of F- in total water-soluble ions ranged from 22.2% to 32.5%. The fume purification technologies significantly influenced the issues and the emission characteristics of water-soluble ions in fumes of coal fired boilers. Na+ was a characteristic water-soluble ion for the desulfurizer NaOH, NH4+ and NO3+ were characteristic for the desulfurizer NH4HCO3, and Mg2+ was characteristic for the desulfurizer MgO, but the Ca2+ emission was not increased by addition of the desulfurizer CaO or CaCO3 The concentrations of NH4+ and NO3- in fumes of thermal power plant were lower than those in fumes of industrial or heating coal fired boilers. The form of water-soluble ions was significantly correlated with fume temperature. The most water-soluble ions were in superfine state at higher fume temperature and were not easily captured by the filter membrane. PMID:26387296

  19. Varicella Disease in Beijing in the Era of Voluntary Vaccination, 2007 to 2010

    PubMed Central

    Lu, Li; Wang, Chengbin; Suo, Luodan; Li, Juan; Liu, Weixiang; Pang, Xinghuo; Seward, Jane F.

    2015-01-01

    Background In China, varicella vaccine has been available in the private sector to children ≥12 months of age since 1998 with a single-dose indication. In December 2006, varicella became a notifiable disease in Beijing. We used surveillance data to describe varicella vaccine uptake from 2005 to 2010 and varicella epidemiology in Beijing from 2007 to 2010. Methods Limited sociodemographic and clinical information was available from the passive surveillance system. Varicella vaccine coverage was estimated for each year for children born between 2004 and 2008 using the number of children in the immunization registry of each birth year as the denominator without adjustment for history of varicella. Results Vaccine coverage increased within each birth cohort between 2005 and 2010. The coverage at 2 years of age increased from 62.4% in 2005 to 74.1% in 2010 and was 80.4% in children 3–6 years of age in 2010. Between 2007 and 2010, 15,544 to 18,256 varicella cases were reported annually with stable overall incidence (range: 1.0–1.1/1000 persons), but the incidence in children 1–4 years of age decreased significantly from 6.2 per 1000 children in 2007 to 4.4 per 1000 children in 2010 (P < 0.001). Among adults (≥20 years of age), there were significant increases in the number and proportion of cases from 2557 (16.5%) in 2007 to 4277 (23.4%) in 2010 (P < 0.001). Conclusions Moderately high 1-dose vaccine coverage in young children has been achieved with declining disease incidence, but varicella remains a common, seasonal disease in the population. Current epidemiology suggests that a government-funded varicella vaccine program that includes catch-up vaccination for older children, adolescents and adults needs consideration. PMID:23429564

  20. Cognitive distortions based on MDS configuration and sketch mapping: a case study in Beijing

    NASA Astrophysics Data System (ADS)

    Shen, Si; Xue, Lulu; Wu, Lun; Liu, Yu

    2007-06-01

    As an emerging field, cognitive map kept playing a significant role in geography these decades. To date, there are two dominant methods to externalize human's internal cognitive map, namely, multidimensional scaling (MDS) and skech mapping. However, among most recent researches on cognitive map, the differences between both methods are always ignored. The usage of one method over another is still under scrutiny. In order to shed light on the similarity or distinctions of MDS configuration and sketch mapping, we conducted an experiment on Beijing residents by requesting a sketch of the region within 3rd Ring and meanwhile extracting distance estimates between 8 landmarks. Employing the Bidimensional regression along with standard deviational ellipse, we studied the global and local distortions among two kinds of cognitive maps and quantitatively measure the overall and local cognitive maps distortions. Besides, we use Monte Carlo simulation method to calculate the radius of distortion for the Distortion Index (DI). It shows that the average cognitive distortion of habitants in Beijing is 2km to 3km, and the distortion takes 2nd-ring road as a border, displaying a southwest-northeast diagonal stretch and an east-west contracted tendency. The distortion in the two methods is remarkably both correlated with factors, such as travel frequency and years of residence. Comparing two methods, it turned out that sketch map was more consistent with real map, while the distortion orientations of sketch map resembled MDS configuration. Finally, we gave possible reasons with regard to above conclusions and advices for future usage of two methods.

  1. Effects of Urban Landscape Pattern on PM2.5 Pollution--A Beijing Case Study.

    PubMed

    Wu, Jiansheng; Xie, Wudan; Li, Weifeng; Li, Jiacheng

    2015-01-01

    PM2.5 refers to particulate matter (PM) in air that is less than 2.5 μm in aerodynamic diameter, which has negative effects on air quality and human health. PM2.5 is the main pollutant source in haze occurring in Beijing, and it also has caused many problems in other cities. Previous studies have focused mostly on the relationship between land use and air quality, but less research has specifically explored the effects of urban landscape patterns on PM2.5. This study considered the rapidly growing and heavily polluted Beijing, China. To better understand the impact of urban landscape pattern on PM2.5 pollution, five landscape metrics including PLAND, PD, ED, SHEI, and CONTAG were applied in the study. Further, other data, such as street networks, population density, and elevation considered as factors influencing PM2.5, were obtained through RS and GIS. By means of correlation analysis and stepwise multiple regression, the effects of landscape pattern on PM2.5 concentration was explored. The results showed that (1) at class-level, vegetation and water were significant landscape components in reducing PM2.5 concentration, while cropland played a special role in PM2.5 concentration; (2) landscape configuration (ED and PD) features at class-level had obvious effects on particulate matter; and (3) at the landscape-level, the evenness (SHEI) and fragmentation (CONTAG) of the whole landscape related closely with PM2.5 concentration. Results of this study could expand our understanding of the role of urban landscape pattern on PM2.5 and provide useful information for urban planning. PMID:26565799

  2. Role of secondary aerosols in haze formation in summer in the Megacity Beijing.

    PubMed

    Han, Tingting; Liu, Xingang; Zhang, Yuanhang; Qu, Yu; Zeng, Limin; Hu, Min; Zhu, Tong

    2015-05-01

    A field experiment from 18 August to 8 September 2006 in Beijing, China, was carried out. A hazy day was defined as visibilityBeijing. PMID:25968258

  3. Longitudinal Associations between Triglycerides and Metabolic Syndrome Components in a Beijing Adult Population, 2007-2012

    PubMed Central

    Tao, Li-Xin; Yang, Kun; Liu, Xiang-Tong; Cao, Kai; Zhu, Hui-Ping; Luo, Yan-Xia; Guo, Jin; Wu, Li-Juan; Li, Xia; Guo, Xiu-Hua

    2016-01-01

    Background:Longitudinal associations between triglycerides (TG) and other metabolic syndrome (MetS) components have rarely been reported. The purpose was to investigate the longitudinal association between TG and other MetS components with time. Methods:The longitudinal study was established in 2007 on individuals who attended health check-ups at Beijing Tongren Hospital and Beijing Xiaotangshan Hospital. Data used in this study was based on 7489 participants who had at least three health check-ups over a period of 5-year follow up. Joint model was used to explore longitudinal associations between TG and other MetS components after adjusted for age. Results:There were positive correlations between TG and other MetS components except for high density lipoprotein (HDL), and the correlations increased with time. A negative correlation was displayed between TG and HDL, and the correlation also increased with time. Among all five pairs of TG and other MetS components, the marginal correlation between TG and body mass index (BMI) was the largest for both men and women. The marginal correlation between TG and fasting plasma glucose was the smallest for men, while the marginal correlation between TG and diastolic blood pressure was the smallest for women. Conclusions: The longitudinal association between TG and other MetS components increased with time. Among five pairs of TG and other MetS components, the longitudinal correlation between TG and BMI was the largest. It is important to closely monitor subjects with high levels of TG and BMI in health check-up population especially for women, because these two components are closely associated with development of hypertension, diabetes, cardiovascular disease and other metabolic diseases. PMID:27279794

  4. Aldehydes in relation to air pollution sources: A case study around the Beijing Olympics

    NASA Astrophysics Data System (ADS)

    Altemose, Brent; Gong, Jicheng; Zhu, Tong; Hu, Min; Zhang, Liwen; Cheng, Hong; Zhang, Lin; Tong, Jian; Kipen, Howard M.; Ohman-Strickland, Pamela; Meng, Qingyu; Robson, Mark G.; Zhang, Junfeng

    2015-05-01

    This study was carried out to characterize three aldehydes of health concern (formaldehyde, acetaldehyde, and acrolein) at a central Beijing site in the summer and early fall of 2008 (from June to October). Aldehydes in polluted atmospheres come from both primary and secondary sources, which limits the control strategies for these reactive compounds. Measurements were made before, during, and after the Beijing Olympics to examine whether the dramatic air pollution control measures implemented during the Olympics had an impact on concentrations of the three aldehydes and their underlying primary and secondary sources. Average concentrations of formaldehyde, acetaldehyde and acrolein were 29.3 ± 15.1 μg/m3, 27.1 ± 15.7 μg/m3 and 2.3 ± 1.0 μg/m3, respectively, for the entire period of measurements, all being at the high end of concentration ranges measured in cities around the world in photochemical smog seasons. Formaldehyde and acrolein increased during the pollution control period compared to the pre-Olympic Games, followed the changing pattern of temperature, and were significantly correlated with ozone and with a secondary formation factor identified by principal component analysis (PCA). In contrast, acetaldehyde had a reduction in mean concentration during the Olympic air pollution control period compared to the pre-Olympic period and was significantly correlated with several pollutants emitted from local emission sources (e.g., NO2, CO, and PM2.5). Acetaldehyde was also more strongly associated with primary emission sources including vegetative burning and oil combustion factors identified through the PCA. All three aldehydes were lower during the post-Olympic sampling period compared to the before and during Olympic periods, likely due to seasonal and regional effects. Our findings point to the complexity of source control strategies for secondary pollutants.

  5. On-road pollutant emission and fuel consumption characteristics of buses in Beijing.

    PubMed

    Wang, Aijuan; Ge, Yunshan; Tan, Jianwei; Fu, Mingliang; Shah, Asad Naeem; Ding, Yan; Zhao, Hong; Liang, Bin

    2011-01-01

    On-road emission and fuel consumption (FC) levels for Euro III and IV buses fueled on diesel and compressed natural gas (CNG) were compared, and emission and FC characteristics of buses were analyzed based on approximately 28,700 groups of instantaneous data obtained in Beijing using a portable emissions measurement system (PEMS). The experimental results revealed that NOx and PM emissions from CNG buses were decreased by 72.0% and 82.3% respectively, compared with Euro IV diesel buses. Similarly, these emissions were reduced by 75.2% and 96.3% respectively, compared with Euro III diesel buses. In addition, CO2, CO, HC, NOx, PM emissions and FC of Euro IV diesel buses were reduced by 26.4%, 75.2%, 73.6%, 11.4%, 79.1%, and 26.0%, respectively, relative to Euro III diesel buses. The CO2, CO, HC, NOx, PM emissions and FC factors all decreased with bus speed increased, while increased as bus acceleration increased. At the same time, the emission/FC rates as well as the emission/FC factors exhibited a strong positive correlation with the vehicle specific power (VSP). They all were the lowest when VSP < 0, and then rapidly increased as VSP increased. Furthermore, both the emission/FC rates and emission/FC factors were the highest at accelerations, higher at cruise speeds, and the lowest at decelerations for non-idling buses. These results can provide a base reference to further estimate bus emission and FC inventories in Beijing. PMID:21520811

  6. Monitoring trends of urban development and environmental impact of Beijing, 1999-2006.

    PubMed

    Liu, Gengyuan; Yang, Zhifeng; Chen, Bin; Ulgiati, Sergio

    2011-08-15

    The high rates of environmental change and accelerated species loss in the urban development process should be quantified to rebalance the social and environmental dimensions of sustainability. In this study, an emergy-based environmental impact assessment model is designed according to the framework of the Eco-Indicator 99 for monitoring the negative effects on human well-being and ecosystem integrity in the urban development system of Beijing from 1999 to 2006. The environmental impact assessment model is based on the sustainability promotion perspective, and emphasizes the determinants of human health and ecosystem integrity in the urban development process. It is vital that the links among human health, ecosystem integrity and urban sustainability are therefore considered especially from the perspective of a supply-side environmental cost evaluation (including ecological service supply, ecological and economic losses and investment for treatment). Results suggest that: (1) out of all the pollutants, ecological services were mainly used to dilute sulfur dioxide and NH(3)-N; (2) nitrogen dioxide and greenhouse gases released by the urban system contribute heavily to both ecological and economic losses evaluated in emergy terms; and (3) emissions impact, mainly from airborne pollutants, with small contribution from waterborne emissions, generally increases from 1999 to 2006, undermining the sustainability of Beijing. The emergy synthesis proves to be very appropriate to account for large-scale and indirect costs generated by pollution as side effects of economic activity. Such knowledge is a necessary pre-requisite to perform a reliable cost-benefit evaluation of urban sustainability strategies, and provide guidance for policy decision making to maximize benefits and minimize negative impacts. PMID:21696806

  7. Removal efficiency of particulate matters at different underlying surfaces in Beijing.

    PubMed

    Liu, Jiakai; Mo, Lichun; Zhu, Lijuan; Yang, Yilian; Liu, Jiatong; Qiu, Dongdong; Zhang, Zhenming; Liu, Jinglan

    2016-01-01

    Particulate matter (PM) pollution has been increasingly becoming serious in Beijing and has drawn the attention of the local government and general public. This study was conducted during early spring of 2013 and 2014 to monitor the concentration of PM at three different land surfaces (bare land, urban forest, and lake) in the Olympic Park in Beijing and to analyze its effect on the concentration of meteorological factors and the dry deposition onto different land cover types. The results showed that diurnal variation of PM concentrations at the three different land surfaces had no significant regulations, and sharp short-term increases in PM10 (particulate matter having an aerodynamic diameter <10 μm) occurred occasionally. The concentrations also differed from one land cover type to another at the same time, but the regulation was insignificant. The most important meteorological factor influencing the PM concentration is relative humidity; it is positively correlated with the PM concentration. While in the forests, the wind speed and irradiance also influenced the PM concentration by affecting the capture capacity of trees and dry deposition velocity. Other factors were not correlated with or influenced by the PM concentration. In addition, the hourly dry deposition in unit area (μg/m(2)) onto the three types of land surfaces and the removal efficiency based on the ratio of dry deposition and PM concentration were calculated. The results showed that the forest has the best removal capacity for both PM2.5 (particulate matter having an aerodynamic diameter <2.5 μm) and PM10 because of the faster deposition velocity and relatively low resuspension rate. The lake's PM10 removal efficiency is higher than that of the bare land because of the relatively higher PM resuspension rates on the bare land. However, the PM2.5 removal efficiency is lower than that of the bare land because of the significantly lower dry deposition velocity. PMID:26308922

  8. Molecular characterization and antibiotic resistance of clinical Streptococcus dysgalactiae subsp. equisimilis in Beijing, China.

    PubMed

    Lu, Binghuai; Fang, Yujie; Huang, Lei; Diao, Baowei; Du, Xiaoli; Kan, Biao; Cui, Yanchao; Zhu, Fengxia; Li, Dong; Wang, Duochun

    2016-06-01

    Streptococcus dysgalactiae subsp. equisimilis (SDSE) is presently considered as a human pathogen associated with clinical infection. We characterized 56 SDSE isolates collected from two tertiary hospitals in Beijing, China. Sixteen distinct emm types/subtypes were detected, dominated by stG245.0 (32.1%), stG652.0 (10.7%), stG6.1 (10.7%) and stG485.0 (10.7%), and a novel stG840.0 variant type was identified. All isolates possessed virulence genes of sagA and scpA, and most carried slo (98.2%), ska (98.2%) and speG(dys) (35.7%). By multilocus sequence typing (MLST) analysis, 17 individual sequence types (STs) were distinguished, including 7 newly-identified STs (26.8% of isolates), of which ST127 (30.4%), ST7 (12.5%) and ST44 (10.7%) dominated. Meanwhile, pulsed-field gel electrophoresis (PFGE) analysis revealed 33 pattern types (PTs), which were further combined into 16 pattern clusters (PCs), and 59.3% of isolates were distributed into 2 dominant PCs. Notably, emm types had both close relationship and consistency with STs and PFGE PCs. Furthermore, of 56 SDSE isolates, the predominant antibiotic resistances were erythromycin (71.4%), clindamycin (71.4%) and tetracycline (60.7%). Correspondingly, the prevalent resistance genes of macrolide and tetracycline were erm(B) (78.6%) and tet(M) (73.2%). In addition, multiple point mutations of parC, one of fluoroquinolone resistance genes, were observed (accounting for 75%), and were divided into 12 types, with parC 07 as the predominant type. Our data suggested the wide molecular diversity and distinctive regional features of SDSE from clinical infection in Beijing, China. PMID:26925701

  9. Residue levels of hexachlorocyclohexane and dichlorodiphenyltrichloroethane in human milk collected from Beijing.

    PubMed

    Song, Shuling; Ma, Xiaodong; Tong, Ling; Tian, Qin; Huang, Yi; Yin, Shaoquan; Sun, Hongbin

    2013-09-01

    Forty-eight human breast milk samples were collected from mothers in Beijing. The hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) (including α-HCH, β-HCH, γ-HCH, δ-HCH, p,p'-DDE, p,p'-DDD, o,p'-DDT, and p,p'-DDT) contents of the samples were determined by gas chromatography/electron capture detection and gas chromatography/mass spectrometry. α-HCH, β-HCH, γ-HCH, p,p'-DDE, p,p'-DDD, and p,p'-DDT were detected at rates of 20, 100, 10, 100, 10, and 22 %, respectively. The average residue levels in the samples were 174.6 ng/g fat for β-HCH, 333.8 ng/g fat for p,p'-DDE, 6.57 ng/g fat for α-HCH, 7.67 ng/g fat for γ-HCH, 4.18 ng/g fat for p,p'-DDD, and 11.4 ng/g fat for p,p'-DDT. The results showed that the infants' daily intake levels of HCH and DDT were 0.95 and 1.76 μg/kg body weight/day, respectively. Our result suggested that the total residue level of these organochlorine pesticides in breast milk from Beijing decreased and was lower than that from other coastal and heavy industrial cities in China. On the other hand, the levels of HCH and DDT were higher than those from some developed countries, but lower than those from other developing countries such as India. PMID:23355024

  10. Prevalence of Overweight and Obesity and Weight Loss Practice among Beijing Adults, 2011

    PubMed Central

    Cai, Li; Han, Xiaoyan; Qi, Zhi; Li, Zhe; Zhang, Yumei; Wang, Peiyu; Liu, Aiping

    2014-01-01

    Objective This study aims to determine the up-to-date prevalence of overweight and obesity, the distributions of body weight perception and weight loss practice in Beijing adults. Methods A cross-sectional study was conducted in 2011. A total of 2563 men and 4088 women aged 18–79 years from the general population were included. Data were obtained from questionnaire and physical examination. Results The prevalence of overweight (BMI 24–27.9 kg/m2) and obesity (BMI≥28 kg/m2) was 42.1% and 20.3% in men and 35.6% and 17.1% in women, respectively. Age was inversely associated with overweight in both sexes, and obesity in women. Education level was negatively associated with overweight and obesity in women but not in men. Only 49.1% men and 58.3% women had a correct perception of their body weight. Underestimation of body weight was more common than overestimation, especially in men, the older people, and those with low education level. The percentage of taking action to lose weight was inversely associated with men and old age, and positively associated with higher education level, higher BMI, and self-perception as “fat” (OR = 3.78 in men, OR = 2.91 in women). Only 26.1% of overweight/obese individuals took action to lose weight. The top two weight loss practices were to reduce the amount of food intake and exercise. Conclusion Overweight and obesity were highly prevalent with high incorrect body weight perceptions in the general adult population in Beijing. Weight loss practice was poor in overweight and obese individuals. Actions at multiple levels are needed to slow or control this overweight and obesity epidemic. PMID:25225884

  11. Source of Personal Exposure to PM2.5 among College Students in Beijing, China

    NASA Astrophysics Data System (ADS)

    Xie, Qiaorong; Zhu, Xianlei; Li, Xiang; Hui, Fan; Fu, Xianqiang; Zhang, Qiangbin

    2015-04-01

    The health risk from exposure to airborne particles arouses increasing public concern in Beijing, a megacity in China, where concentration of PM2.5 frequently exceeds the guideline values of World Health Organization (WHO). To investigate daily exposure to PM2.5, a personal exposure study was conducted for college students. The purpose of this study was to measure the daily PM2.5 personal exposures of students, to quantify the contributions of various microenvironments to personal exposure since students spend more than 85% of their time indoors, and to apportion the contributions of PM2.5 indoors origin and outdoor origin. In this work, a total of 320 paired indoor and outdoor PM2.5 samples were collected at eight types of microenvironments in both China University of Petroleum (suburban area) and Tsinghua University (urban area). The microenvironments were selected based on the time-activity diary finished by 1500 students from both universities. Simultaneously, the air exchange rate was measured in each microenvironment. PM2.5, elements, inorganic ions and polycyclic aromatic hydrocarbons in the samples were determined. The peak concentrations were observed in dinning halls, whereas PM2.5 in dormitories was the largest contributor to personal exposure because students spend more than half of a day there. Furthermore, source apportionment by positive matrix factorization (PMF) will be carried out to understand the source of personal exposure to PM2.5. Especially, efforts will be put on determing the contributions of primary combustion, secondary sulfate and organics, secondary nitrate, and mechanically generated PM, which present different infiltration behavior and are indoor PM2.5 of ambient origin, with help of air exchange rate data. The results would be benefit for refining the understanding of the contribution of PM2.5 of ambient (outdoor) origin to the daily PM2.5 personal exposures. Acknowledgments:This study has been funded by Beijing Municipal Commission

  12. Polybrominated diphenyl ethers in atmosphere from three different typical industrial areas in Beijing, China.

    PubMed

    Dong, Yuan; Fu, Shan; Zhang, Yongfei; Nie, Haifeng; Li, Zheng

    2015-03-01

    Three common industries that cause polybrominated diphenyl ethers (PBDEs) pollution in Beijing, China, are solid waste incineration, chemical manufacturing, and coal-fired thermal power generation. This study was conducted to determine both the concentrations and profiles of 42 PBDEs in gaseous and particulate matter (including PM2.5, PM2.5-10, and total suspended particulate (TSP)) from the major industries listed above at three sites in Beijing. The total concentration of PBDEs (defined as the sum of 42 congeners in gas and TSP) were 60.5-216 pg m(-3) at the solid waste incineration plant, 71.8-7500 pg m(-3) at the chemical plant, and 34.4-454 pg m(-3) at the coal-fired thermal power plant. The results indicate that the components of PBDE in gas were similar between three industrial sites, and the dominant congener was tri-BDEs. However, in particulate matter, the dominant BDEs were different between the three sites, possibly because they originated from different sources. In particulate matter, the dominant PBDEs were penta-BDEs at the solid waste incineration plant, deca-BDE at the coal-fired thermal power plant, and tetra-BDEs and deca-BDE at the chemical plant. Source analysis revealed that PBDE contamination might be associated with the use of different commercial PBDE flame-retardant mixtures. Results from a previous risk assessment indicated that the risk to human health was low. However, results from this study suggest that there is a potential threat associated with human exposure to PBDEs for the residents near these industrial sites. PMID:25491762

  13. Mixing layer height and its implications for air pollution over Beijing, China

    NASA Astrophysics Data System (ADS)

    Tang, Guiqian; Zhang, Jinqiang; Zhu, Xiaowan; Song, Tao; Münkel, Christoph; Hu, Bo; Schäfer, Klaus; Liu, Zirui; Zhang, Junke; Wang, Lili; Xin, Jinyuan; Suppan, Peter; Wang, Yuesi

    2016-03-01

    The mixing layer is an important meteorological factor that affects air pollution. In this study, the atmospheric mixing layer height (MLH) was observed in Beijing from July 2009 to December 2012 using a ceilometer. By comparison with radiosonde data, we found that the ceilometer underestimates the MLH under conditions of neutral stratification caused by strong winds, whereas it overestimates the MLH when sand-dust is crossing. Using meteorological, PM2.5, and PM10 observational data, we screened the observed MLH automatically; the ceilometer observations were fairly consistent with the radiosondes, with a correlation coefficient greater than 0.9. Further analysis indicated that the MLH is low in autumn and winter and high in spring and summer in Beijing. There is a significant correlation between the sensible heat flux and MLH, and the diurnal cycle of the MLH in summer is also affected by the circulation of mountainous plain winds. Using visibility as an index to classify the degree of air pollution, we found that the variation in the sensible heat and buoyancy term in turbulent kinetic energy (TKE) is insignificant when visibility decreases from 10 to 5 km, but the reduction of shear term in TKE is near 70 %. When visibility decreases from 5 to 1 km, the variation of the shear term in TKE is insignificant, but the decrease in the sensible heat and buoyancy term in TKE is approximately 60 %. Although the correlation between the daily variation of the MLH and visibility is very poor, the correlation between them is significantly enhanced when the relative humidity increases beyond 80 %. This indicates that humidity-related physicochemical processes is the primary source of atmospheric particles under heavy pollution and that the dissipation of atmospheric particles mainly depends on the MLH. The presented results of the atmospheric mixing layer provide useful empirical information for improving meteorological and atmospheric chemistry models and the forecasting

  14. Mixing ratio and carbon isotopic composition investigation of atmospheric CO2 in Beijing, China.

    PubMed

    Pang, Jiaping; Wen, Xuefa; Sun, Xiaomin

    2016-01-01

    The stable isotope composition of atmospheric CO2 can be used as a tracer in the study of urban carbon cycles, which are affected by anthropogenic and biogenic CO2 components. Continuous measurements of the mixing ratio and δ(13)C of atmospheric CO2 were conducted in Beijing from Nov. 15, 2012 to Mar. 8, 2014 including two heating seasons and a vegetative season. Both δ(13)C and the isotopic composition of source CO2 (δ(13)CS) were depleted in the heating seasons and enriched in the vegetative season. The diurnal variations in the CO2 mixing ratio and δ(13)C contained two peaks in the heating season, which are due to the effects of morning rush hour traffic. Seasonal and diurnal patterns of the CO2 mixing ratio and δ(13)C were affected by anthropogenic emissions and biogenic activity. Assuming that the primary CO2 sources at night (22:00-04:00) were coal and natural gas combustion during heating seasons I and II, an isotopic mass balance analysis indicated that coal combustion had average contributions of 83.83±14.11% and 86.84±12.27% and that natural gas had average contributions of 16.17±14.11% and 13.16±12.27%, respectively. The δ(13)C of background CO2 in air was the main error source in the isotopic mass balance model. Both the mixing ratio and δ(13)C of atmospheric CO2 had significant linear relationships with the air quality index (AQI) and can be used to indicate local air pollution conditions. Energy structure optimization, for example, reducing coal consumption, will improve the local air conditions in Beijing. PMID:26363727

  15. The characteristics of lightning risk and zoning in Beijing simulated by a risk assessment model

    NASA Astrophysics Data System (ADS)

    Hu, H.; Wang, J.; Pan, J.

    2014-08-01

    In this study, the cloud-to-ground (CG) lightning flash/stroke density was derived from the lightning location finder (LLF) data recorded between 2007 and 2011. The vulnerability of land surfaces was then assessed from the classification of the study areas into buildings, outdoor areas under the building canopy and open-field areas, which makes it convenient to deduce the location factor and confirm the protective capability. Subsequently, the potential number of dangerous lightning events at a location could be estimated from the product of the CG stroke density and the location's vulnerability. Although the human beings and all their material properties are identically exposed to lightning, the lightning casualty risk and property loss risk was assessed respectively due to their vulnerability discrepancy. Our analysis of the CG flash density in Beijing revealed that the valley of JuMaHe to the southwest, the ChangPing-ShunYi zone downwind of the Beijing metropolis, and the mountainous PingGu-MiYun zone near the coast are the most active lightning areas, with densities greater than 1.5 flashes km-2 year-1. Moreover, the mountainous northeastern, northern, and northwestern rural areas are relatively more vulnerable to lightning because the high-elevation terrain attracts lightning and there is little protection. In contrast, lightning incidents by induced lightning are most likely to occur in densely populated urban areas, and the property damage caused by lightning here is more extensive than that in suburban and rural areas. However, casualty incidents caused by direct lightning strokes seldom occur in urban areas. On the other hand, the simulation based on the lightning risk assessment model (LRAM) demonstrates that the casualty risk is higher in rural areas, whereas the property loss risk is higher in urban areas, and this conclusion is also supported by the historical casualty and damage reports.

  16. Numerical study on the impacts of heterogeneous reactions on ozone formation in the Beijing urban area

    NASA Astrophysics Data System (ADS)

    Xu, Jun; Zhang, Yuanhang; Wang, Wei

    2006-12-01

    The air quality model CMAQ-MADRID (Community Multiscale Air Quality-Model of Aerosol Dynamics, Reaction, Ionization and Dissolution) was employed to simulate summer O3 formation in Beijing China, in order to explore the impacts of four heterogeneous reactions on O3 formation in an urban area. The results showed that the impacts were obvious and exhibited the characteristics of a typical response of a VOC-limited regime in the urban area. For the four heterogeneous reactions considered, the NO2 and HO2 heterogeneous reactions have the most severe impacts on O3 formation. During the O3 formation period, the NO2 heterogeneous reaction increased new radical creation by 30%, raising the atmospheric activity as more NO→NO2 conversion occurred, thus causing the O3 to rise. The increase of O3 peak concentration reached a maximum value of 67 ppb in the urban area. In the morning hours, high NO titration reduced the effect of the photolysis of HONO, which was produced heterogeneously at night in the surface layer. The NO2 heterogeneous reaction in the daytime is likely one of the major reasons causing the O3 increase in the Beijing urban area. The HO2 heterogeneous reaction accelerated radical termination, resulting in a decrease of the radical concentration by 44% at the most. O3 peak concentration decreased by a maximum amount of 24 ppb in the urban area. The simulation results were improved when the heterogeneous reactions were included, with the O3 and HONO model results close to the observations.

  17. PBDEs, hydroxylated PBDEs and methoxylated PBDEs in bivalves from Beijing markets.

    PubMed

    Liu, Xitao; Jiao, Ying; Lin, Chunye; Sun, Ke; Zhao, Ye

    2014-09-01

    The structural analogues of polybrominated diphenyl ethers (PBDEs), hydroxylated PBDEs (OH-PBDEs) and methoxylated PBDEs (MeO-PBDEs) have been attracting increasing concern in recent years. Five bivalve species (blue mussel, short-necked clam, surf clam, ark shell and razor clam) were collected from Beijing markets, and the concentrations of seven PBDEs, four OH-PBDEs and fourteen MeO-PBDEs in the bivalves were measured. The seasonal variations of these three types of polybrominated compound in blue mussels were also monitored. The results indicate that the levels of ΣPBDEs in this study were comparable to those in short-necked clams from Liaodong Bay, China, with BDE47 as the dominant congener. For the ortho-MeO-PBDEs, 6-MeO-BDE47 was found at higher concentrations than the others, while for the meta- and para-MeO-PBDEs, 4'-MeO-BDE17 was found at higher concentrations. 6-OH-BDE-47 was the most abundant congener among the 4 measured OH-PBDEs, followed by 6-OH-BDE-137 and 6-OH-BDE-85. The levels of OH-PBDEs and MeO-PBDEs in bivalves from Beijing markets were much lower than the corresponding compounds in blue mussels from the Baltic Sea. In the blue mussels collected in April, June and September of 2012, apparent seasonal variations were observed for these three types of polybrominated compounds, but the acidic components displayed different trends from the neutral components, with PBDEs and MeO-PBDEs showing the highest concentrations in June, while OH-PBDEs had the lowest concentrations in June. This difference in seasonal variations between the neutral components and the acidic components may be explained by their different sources and transformation/elimination mechanisms. PMID:24636323

  18. Characterization of submicron particles during biomass burning and coal combustion periods in Beijing, China.

    PubMed

    Zhang, J K; Cheng, M T; Ji, D S; Liu, Z R; Hu, B; Sun, Y; Wang, Y S

    2016-08-15

    An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was deployed along with other observation instruments to measure the characteristics of PM1 (particulate matter with a vacuum aerodynamic diameter of ≤1μm) during the biomass burning period (October 1 to 27; BBP) and the coal combustion period (December 10 to 31; CCP) in Beijing in 2014. The average PM1 mass concentrations during the BBP and CCP were 82.3 and 37.5μgm(-3), respectively. Nitrate, ammonium and other pollutants emitted by the burning processes, especially coal combustion, increased significantly in association with increased pollution levels. Positive matrix factorization (PMF) was applied to a unified high-resolution mass spectra database of organic species with NO(+) and NO2(+) ions to discover the relationships between organic and inorganic species. One inorganic factor was identified in both periods, and another five and four distinct organic factors were identified in the BBP and CCP, respectively. Secondary organic aerosols (SOAs) accounted for 55% of the total organic aerosols (OAs) during the BBP, which is higher than the proportion during the CCP (oxygenated OA, 40%). The organic nitrate and inorganic nitrate were first successfully separated through the PMF analysis based on the HR-ToF-AMS observations in Beijing, and organic nitrate components accounted for 21% and 18% of the total nitrate mass during the BBP and CCP, respectively. Although the PM1 mass concentration during the CCP was much lower than in the BBP, the average concentration of polycyclic aromatic hydrocarbons (PAHs) during the CCP (107.3±171.6ngm(-3)) was ~5 times higher than that in the BBP (21.9±21.7ngm(-3)). PMID:27110992

  19. On-road emission characteristics of VOCs from diesel trucks in Beijing, China

    NASA Astrophysics Data System (ADS)

    Yao, Zhiliang; Shen, Xianbao; Ye, Yu; Cao, Xinyue; Jiang, Xi; Zhang, Yingzhi; He, Kebin

    2015-02-01

    This paper is the first in our series of papers aimed at understanding the volatile organic compound (VOC) emissions of vehicles in Beijing by conducting on-board emission measurements. This paper focuses on diesel vehicles. In this work, 18 China III diesel vehicles, including seven light-duty diesel trucks (LDDTs), four medium-duty diesel trucks (MDDTs) and seven heavy-duty diesel trucks (HDDTs), were examined when the vehicles were driven on predesigned fixed test routes in Beijing in China using a portable emissions measurement system (PEMS). Tedlar bag sampling and 2,4-dinitrophenyhydrazine (DNPH) cartridge sampling were used to collect VOC species, and gas chromatography-mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC) were used to analyze these samples. We obtained the VOC emission factors and relative compositions for diesel trucks of different sizes under different driving patterns. In total, 64 VOC species were quantified in this study, including 25 alkanes, four alkenes, 13 aromatics, 13 carbonyls and nine other compounds. The emission factors of the total VOCs based on mileage traveled for HDDTs were higher than those of LDDTs and MDDTs. Carbonyls, aromatics and alkanes were the dominant VOC species. Carbonyls accounted for 42.7%-69.2% of the total VOCs in the three types of tested diesel trucks. The total VOC emission factors of the tested vehicles that were driven on non-highway routes were 1.5-2.0 times higher than those of the vehicles driven on the highway. As for the OFP calculation results, with increased vehicle size, the ozone formation potential presented an increasing trend. Among the VOC components, carbonyls were the primary contributor to OFP. In addition, the OFPs under non-highway driving cycles were 1.3-1.7 times those under highway driving cycles. The results of this study will be helpful in improving our understanding of VOCs emitted from on-road diesel trucks in China.

  20. Evaluation of fungal spore characteristics in Beijing, China, based on molecular tracer measurements

    NASA Astrophysics Data System (ADS)

    Liang, Linlin; Engling, Guenter; He, Kebin; Du, Zhenyu; Cheng, Yuan; Duan, Fengkui

    2013-03-01

    PM2.5 (particulate matter with aerodynamic diameters less than 2.5 μm) and PM10 (particulate matter with aerodynamic diameters less than 10 μm) samples were collected by high-volume air samplers simultaneously at a rural site and an urban site in Beijing, China. Various carbohydrates were quantified by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), including the sugar alcohols mannitol and arabitol, recently proposed as molecular tracers for fungal aerosol. The annual average concentrations of arabitol in PM2.5 and PM10 at the urban site were 7.4 ± 9.4 and 21.0 ± 20.4 ng m-3, and the respective mannitol concentrations were 10.3 ± 9.5 and 31.9 ± 26.9 ng m-3. During summer and autumn, higher arabitol and mannitol levels than during spring and winter were observed in coarse particles, probably due to different dominant sources of fungal spores in different seasons. In the dry season (i.e., winter and spring) in Beijing, probably only the suspension from exposed surfaces (e.g., soil resuspension, transported dust, etc) can be regarded as the main sources for fungal aerosols. On the other hand, in summer and autumn, fungal spores in the atmosphere can be derived from more complex sources, including plants, vegetation decomposition and agricultural activity, such as ploughing; these fungal spore sources may contribute more to coarse PM. Moreover, statistical analysis according to typical seasonal patterns, including a dry season (December 2010 to March 2011) and a wet season (July to September 2011), revealed different variations of fungal spores in different seasons. Although fungal spore levels at rural sites were reported to be consistently higher than those at urban sites in other studies, our findings showed the opposite pattern, indicating a high abundance of fungal spores in the urban area of this Chinese megacity.

  1. [Exploring the Severe Haze in Beijing During December, 2015: Pollution Process and Emissions Variation].

    PubMed

    Xue, Yi-feng; Zhou, Zhen; Nie, Teng; Pan, Tao; Qi, Jun; Nie, Lei; Wang, Zhan-shan; Li, Yun-ting; Li, Xue-feng; Tian, He-zhong

    2016-05-15

    Severe haze episodes shrouded Beijing and its surrounding regions again during December, 2015, causing major environmental and health problems. Beijing authorities had launched two red alerts for atmospheric heavy pollution in this period, adopted a series of emergency control measures to reduce the emissions from major pollution sources. To better understand the pollution process and emissions variation during these extreme pollution events, we performed a model-assisted analysis of the hourly observation data of PM₂.₅, and meteorological parameters combined with the emissions variation of pollution sources. The synthetic analysis indicated that: (1) Compared with the same period of last year, the emissions of atmospheric pollution sources decreased in December 2015. However, the emission levels of primary pollutants were still rather high, which were the main intrinsic causes for haze episodes, and the unfavorable diffusion conditions represented the important external factor. High source emissions and meteorological factors together led to this heavy air pollution process. (2) Emergency control measures taken by the red alert for heavy air pollution could decrease the pollutants emission by about 36% and the PM₂.₅ concentrations by 11% to 21%. Though the implementation of red alert could not reverse the evolution trend of heavier pollution, it indeed played an active role in mitigation of PM₂.₅ pollution aggravating. (3) Under the heavy pollution weather conditions, air pollutants continued to accumulate in the atmosphere, and the maximum effect by taking emergency measures occurred 48-72 hours after starting the implementation; therefore, the best time for executing emergency measures should be 36-48 hours before the rapid rise of PM₂.₅ concentration, which requires a more powerful demand on the accuracy of air quality forecast. PMID:27506009

  2. Baseline Blood Levels of Manganese, Lead, Cadmium, Copper, and Zinc in Residents of Beijing Suburb

    PubMed Central

    Zhang, Long-Lian; Lu, Ling; Pan, Ya-Juan; Ding, Chun-Guang; Xu, Da-Yong; Huang, Chuan-Feng; Pan, Xing-Fu; Zheng, Wei

    2015-01-01

    Baseline blood concentrations of metals are important references for monitoring metal exposure in environmental and occupational settings. The purpose of this study was to determine the blood levels of manganese (Mn), copper (Cu), zinc (Zn), lead (Pb), and cadmium (Cd) among the residents (aged 12–60 years old) living in the suburb southwest of Beijing in China and to compare the outcomes with reported values in various developed countries. Blood samples were collected from 648 subjects from March 2009 to February 2010. Metal concentrations in the whole blood were determined by ICP-MS. The geometric means of blood levels of Mn, Cu, Zn, Pb and Cd were 11.4, 802.4, 4665, 42.6, and 0.68 μg/L, respectively. Male subjects had higher blood Pb than the females, while the females had higher blood Mn and Cu than the males. There was no gender difference for blood Cd and Zn. Smokers had higher blood Cu, Zn, and Cd than nonsmokers. There were significant age-related differences in blood levels of all metals studied; subjects in the 17–30 age group had higher blood levels of Mn, Pb, Cu, and Zn, while those in the 46–60 age group had higher Cd than the other age groups. A remarkably lower blood level of Cu and Zn in this population as compared with residents of other developed countries was noticed. Based on the current study, the normal reference ranges for the blood Mn were estimated to be 5.80–25.2 μ/L; for blood Cu, 541–1475 μ/L; for blood Zn, 2349–9492 μ/L; for blood Pb, <100 μ/L; and for blood Cd, <5.30 μ/L in the general population living in Beijing suburbs. PMID:25836720

  3. Effects of Urban Landscape Pattern on PM2.5 Pollution—A Beijing Case Study

    PubMed Central

    Wu, Jiansheng; Xie, Wudan; Li, Weifeng; Li, Jiacheng

    2015-01-01

    PM2.5 refers to particulate matter (PM) in air that is less than 2.5μm in aerodynamic diameter, which has negative effects on air quality and human health. PM2.5 is the main pollutant source in haze occurring in Beijing, and it also has caused many problems in other cities. Previous studies have focused mostly on the relationship between land use and air quality, but less research has specifically explored the effects of urban landscape patterns on PM2.5. This study considered the rapidly growing and heavily polluted Beijing, China. To better understand the impact of urban landscape pattern on PM2.5 pollution, five landscape metrics including PLAND, PD, ED, SHEI, and CONTAG were applied in the study. Further, other data, such as street networks, population density, and elevation considered as factors influencing PM2.5, were obtained through RS and GIS. By means of correlation analysis and stepwise multiple regression, the effects of landscape pattern on PM2.5 concentration was explored. The results showed that (1) at class-level, vegetation and water were significant landscape components in reducing PM2.5 concentration, while cropland played a special role in PM2.5 concentration; (2) landscape configuration (ED and PD) features at class-level had obvious effects on particulate matter; and (3) at the landscape-level, the evenness (SHEI) and fragmentation (CONTAG) of the whole landscape related closely with PM2.5 concentration. Results of this study could expand our understanding of the role of urban landscape pattern on PM2.5 and provide useful information for urban planning. PMID:26565799

  4. Characterization of organic aerosols in Beijing using an aerodyne high-resolution aerosol mass spectrometer

    NASA Astrophysics Data System (ADS)

    Zhang, Junke; Wang, Yuesi; Huang, Xiaojuan; Liu, Zirui; Ji, Dongsheng; Sun, Yang

    2015-06-01

    Fine particle of organic aerosol (OA), mostly arising from pollution, are abundant in Beijing. To achieve a better understanding of the difference in OA in summer and autumn, a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS, Aerodyne Research Inc., USA) was deployed in urban Beijing in August and October 2012. The mean OA mass concentration in autumn was 30±30 μg m-3, which was higher than in summer (13±6.9 μg m-3). The elemental analysis found that OA was more aged in summer (oxygen-to-carbon (O/C) ratio