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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. Folds and Etudes

    ERIC Educational Resources Information Center

    Bean, Robert

    2007-01-01

    In this article, the author talks about "Folds" and "Etudes" which are images derived from anonymous typing exercises that he found in a used copy of "Touch Typing Made Simple". "Etudes" refers to the musical tradition of studies for a solo instrument, which is a typewriter. Typing exercises are repetitive attempts to type words and phrases…

  4. 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…

  5. Beijing Lunar Declaration 2006

    NASA Astrophysics Data System (ADS)

    Foing, B. H.; Wu, J.; Iceum8 Participants

    2008-07-01

    We report to COSPAR the "Lunar Beijing Declaration" from the participants to The Eighth ILEWG International Conference on the Exploration and Utilization of the Moon (ICEUM8, 23-27 July 2006). Further information can be found on ILEWG website http://sci.esa.int/ilewg and selected 38 proceedings papers have been published in Journal of Astronautics of Chinese Society of Astronautics, vol. 28, Suppl., 2007.

  6. Etude des systèmes protoplanétaires

    NASA Astrophysics Data System (ADS)

    Augereau, Jean-Charles

    2000-11-01

    Les disques de poussières et de gaz autour des étoiles rejoignant la Séquence Principale sont les sites de formation des planètes extra-solaires dont l'existence s'est vu confirmée récemment. Cette thèse aborde l'étude de la poussière des environnements circumstellaires. Elle associe des observations spatiales à haute résolution angulaire, la modélisation des propriétés physico-chimiques des poussières et leur comportement optique, la modélisation des disques optiquement fins et la dynamique des planétésimaux à l'origine des grains observés autour des étoiles âgées. Les images obtenues avec le Télescope Spatial Hubble révèlent deux nouveaux disques circumstellaires autour des étoiles HD 141569 et HD 100546, parfois classées dans la catégorie des étoiles de Herbig. Bien que les systèmes présentent des âges proches (~10 millions d'années), les morphologies très différentes des disques mettent en évidence la difficulté pour élaborer un scénario unique d'évolution des systèmes protoplanétaires. L'anneau fin de poussières autour de HR 4796A, une étoile d'âge similaire aux précédentes, est marginalement résolu depuis le sol. La modélisation complète de ce disque permet de reproduire l'ensemble des observations disponibles. Ces résultats impliquent la présence de planétésimaux, à un âge aussi peu avancé, pour repeupler le disque en poussières poreuses et essentiellement amorphes qui sont soufflées par la pression de radiation. Une modélisation dynamique du prototypique disque autour de β Pictoris est proposée. Associée à une description réaliste du comportement optique des grains, cette approche reproduit les caractéristiques générales du disque ainsi que des asymétries plus fines en supposant la présence d'une planète dans un disque de planétésimaux et en tenant compte des effets différentiels de la pression de radiation sur les grains. Enfin, le modèle de disques que j'ai développé est exploit

  7. 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

  8. 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.

  9. Mycobacterium tuberculosis Beijing genotype, northern Malawi.

    PubMed

    Glynn, Judith R; Crampin, Amelia C; Traore, Hamidou; Yates, Malcolm D; Mwaungulu, Frank D; Ngwira, Bagrey M; Chaguluka, Steven D; Mwafulirwa, Donex T; Floyd, Sian; Murphy, Caroline; Drobniewski, Francis A; Fine, Paul E M

    2005-01-01

    In a 7-year population-based study in Malawi, we showed that Beijing genotype tuberculosis (TB) increased as a proportion of TB cases. All the Beijing genotype strains were fully drug sensitive. Contact histories, TB type, and case-fatality rates were similar for Beijing and non-Beijing genotype TB.

  10. 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

  11. Beijing restaurant network

    NASA Astrophysics Data System (ADS)

    Fu, Chun-Hua; Zhnag, Pei-Fang; Wang, Yong-Li; Shi, Jian-Jun; Feng, Ai-Xia; He, Da-Ren

    2008-03-01

    We have empirically studied the restaurants in Beijing and suggested a network description on the system. We define the restaurants as nodes and connect a link between two nodes if the two restaurants sell a common dish. The edge represents the sale competition relationship. In order to describe the competition, we define a node weight, which is the mark given by consumers on an evaluation network (http://www.dianping.com), to the restaurant in cooking the dish. 3338 nodes and 688 dishes have been investigated. We find that both the total node weight, which is defined as the sum of the node weight in all the dishes, and the so-called dish weight, which is defined as the sum of the node weight in one dish, show a rather nice power law distribution.

  12. 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

  13. Wintertime Haze Formation in Beijing

    NASA Astrophysics Data System (ADS)

    Levy Zamora, M. E.

    2015-12-01

    Recent severe haze events in China have attracted significant public attention due to the severely reduced visibility and unprecedentedly high pollutant concentrations. Particular attention has been given to the high concentrations of particulate matter with a diameter less than 2.5 microns (PM2.5), which can exceed several hundred micrograms per cubic meter over several days. During January and February of 2015, a suite of aerosol instruments was deployed in Beijing to directly measure a comprehensive set of aerosol properties, including the particle size distribution, effective density, and chemical composition. In this presentation, we will discuss the particulate matter formation mechanisms, the evolution of aerosol properties throughout the event, and how the winter formation mechanisms compare with the warmer seasons. We show that the periodic cycles of severe haze episodes in Beijing are largely driven by meteorological conditions. During haze events, stagnation typically develops as a result of a low planetary boundary layer and weak southerly wind from polluted industrial source regions. Stronger northerly winds were frequently observed during the clean period, which carry unpolluted air masses from the less populated northern mountainous areas. Nucleation consistently occurs on clean days, producing a high number concentration of nano particles. The particle mass concentration exceeding several hundred micrograms per cubic meter is attributed to the continuous size growth from the nucleation-mode particles (diameter less than 10 nm) over multiple days to produce a high concentration of larger particles (diameter greater than 100 nm). The particle chemical composition in Beijing is similar to those commonly measured in other urban centers, which is indicative of chemical constituents dominated by secondary aerosol formation. Our results reveal that the severe haze formation in Beijing during the wintertime is similar to the mechanism of haze formation

  14. 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

  15. Parent-School Councils in Beijing, China

    ERIC Educational Resources Information Center

    Lewis, Wayne D.; Bjork, Lars G.; Zhao, Yuru; Chi, Bin

    2011-01-01

    This exploratory study examines how schools in Beijing have responded to a Chinese national policy mandate to establish and maintain parent councils. We surveyed principals and parent council members across schools in the Beijing municipality about the establishment and functions of their schools' parent councils. Survey results provide insights…

  16. Beijing: a conference of commitments?

    PubMed

    Davis, S

    1996-05-01

    The author of this article holds the view that the Declaration and Platform for Action at the UN Fourth World Conference on Women held in Beijing in 1995 was the product of the most highly participatory process ever organized under the auspices of the UN. The Declaration and Platform expressed the strongest views on gender equality, empowerment, and justice that governments have ever endorsed. These documents were the consolidation of gains made by women in previous UN conferences. The 135-page Platform can be used at all levels of decision making. Governments and international can be held accountable for its provisions. The Platform exposes the problems violence and exploitation against women and girls as well as the revelation that environmental destruction is due to an unsustainable pattern of consumption and production, particularly in developed countries. Conference participants included about 3000 nongovernmental groups (NGOs). The Women's Linkage Caucus and WEDO served to facilitate the advocacy process by providing briefings on text still under negotiation and providing on-line recommendations from the 1995 and 1994 Commission on the Status of Women preparatory committee meetings. A scoreboard that tracked government's commitment at the 1995 preparatory committee meetings was reinstated in Beijing. The information was conveyed on the Internet. The European Union is credited with diluting the language about government commitment to the Platform. Governments are still given responsibility for implementation, and the need for political will is stressed (paragraph 293). Paragraph 297 indicates the process for implementation of the Platform and coordination with NGOs. Although the Platform recognizes the importance of women's groups and other NGOs, the responsibility for implementation is still given to governments.

  17. 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.

  18. Ecological evaluation of Beijing economy based on emergy indices

    NASA Astrophysics Data System (ADS)

    Jiang, M. M.; Zhou, J. B.; Chen, B.; Yang, Z. F.; Ji, X.; Zhang, L. X.; Chen, G. Q.

    2009-05-01

    An integrated ecological evaluation of the Beijing economy was presented in the paper based on the emergy accounting with the data in 2004. Through calculating environmental and economic inputs within and outside the Beijing economy, this paper discusses the Beijing's resource structure, economic situation and trade status based on a series of emergy indicators. Through the comparison of the systematic indicators of Beijing with those of the selected Chinese cities, the general status of the Beijing economy in China is identified. The results also show that most indicators of Beijing are located at middle levels among the selected Chinese cities. Particularly, the environmental impacts, expressed by the ratio of waste to the renewable emergy, and the ratio of waste to the total emergy use, are 84.2 and 0.26, respectively in Beijing in 2004, which indicate that the Beijing economy is greatly reliant on the imported intensive fuels, goods and services with high empower density and environmental loading.

  19. English Department Reforms at the Hautes Etudes Commerciales: Entering the Nineties.

    ERIC Educational Resources Information Center

    Shanahan, Daniel

    1993-01-01

    Discusses the reforms made in the fall of 1990 in the English department at the Ecole Hautes Etudes Commerciales (Paris, France), which were based on the basis of a combination of literature-culture and second- and foreign-language acquisition pedagogical biases. (four references) (VWL)

  20. 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.

  1. 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

  2. The Human Variome Project Beijing meeting.

    PubMed

    Smith, Timothy D; Robinson, Helen M; Cotton, Richard G H

    2012-04-01

    The Human Variome Project Beijing Meeting, a joint meeting of the Human Variome Project Consortium and the Human Variome Project Chinese Node, was held in Beijing, 8th-12th of December, 2011. The aim of the Human Variome Project is to ensure that all information on genetic variation can be collected, curated, interpreted and shared freely and openly. The meeting officially welcomed the Human Variome Project Chinese Node as a partner of the Human Variome Project and focused on those areas where collaborations between China and the global Human Variome Project Consortium are required to develop and extend the coverage of international gene/disease specific databases.

  3. 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

  4. Air pollution and sports performance in Beijing.

    PubMed

    Lippi, G; Guidi, G C; Maffulli, N

    2008-08-01

    The Beijing Olympics will begin in August 2008 and athletes will face an unpredictable challenge. Based on present data, Beijing is one of the most polluted megacities in the world; the air concentrations of carbon monoxide (CO), ozone, nitrogen oxides (NO and NO2), sulphur dioxide (SO2) and particulate matter approach or exceed the current limits established by U. S. Environmental Protection Agency (EPA). Although the athletes who will be competing in Beijing are physiologically very different to the participants in most published studies, and it is therefore difficult to predict individual responses, there is little doubt that the presence of these air pollutants might be detrimental to athletic performance due to the marked increase (up to 20-fold) in ventilatory rate and concomitant nasal and oral breathing. Moreover, mouth breathing often bypasses the noise during strenuous exercise, increasing the deleterious effects of pollutants on health and athletic performance. Although limited, each decrement in athletic performance would have a potentially deleterious impact on top-class athletes competing in the next Olympics in China. Several Olympic records are regularly broken during the Olympics. Will this be the case for Beijing? PMID:18512178

  5. Municipal solid waste management in Beijing City

    SciTech Connect

    Li Zhenshan Yang Lei; Qu XiaoYan; Sui Yumei

    2009-09-15

    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{sup 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.

  6. 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,…

  7. 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…

  8. The challenge of improving visibility in Beijing

    NASA Astrophysics Data System (ADS)

    Zhang, Q.; Zhang, J.; Xue, H.

    2010-03-01

    The "Blue Sky Project" was proposed in 1998 to investigate by how much emissions should be reduced to increase blue sky frequency in Beijing, which hosted the Summer Olympics in 2008. This paper focuses on the temporal variation of visibility and its dependence on meteorological conditions and suspended particles at Beijing using the hourly observed visibility data in Beijing Capital International Airport (BCIA) from 1999 to 2007. It has been found that about 47.8% (24.2%) of the hours in Beijing are "bad" ("good") hours with visibility below 10 km (equal or higher than 20 km) between 1999 and 2007. Due to the high Relative Humidity (RH), summer is the season with the lowest mean visibility in a year. Although PM10 index was reported in a decreasing trend, the increase of RH has resulted in a decreasing trend of visibility over BCIA in the summer from 1999 to 2007. To ensure blue sky ("good" visibility) for Olympics 2008, daily mean PM10 index should be reduced to 44 from 86.5. This requires that not only vehicle emissions, but also other emissions should be limited. Observations during Olympics 2008 verify that blue-sky-hour rate has been increased significantly after mean PM10 index was reduced to 56, however, the visibility during the same period of 2009 has returned to the mean standard before 2008.

  9. The challenge of improving visibility in Beijing

    NASA Astrophysics Data System (ADS)

    Zhang, Q. H.; Zhang, J. P.; Xue, H. W.

    2010-08-01

    The "Blue Sky Project" was proposed in 1998 to investigate by how much emissions should be reduced to increase blue sky frequency in Beijing, which hosted the Summer Olympics in 2008. This paper focuses on the temporal variation of visibility and its dependence on meteorological conditions and suspended particles at Beijing using the hourly observed visibility data at Beijing Capital International Airport (BCIA) from 1999 to 2007. It has been found that about 47.8% (24.2%) of the hours in Beijing are "bad" ("good") hours with visibility below 10 km (equal or higher than 20 km) between 1999 and 2007. Due to the high Relative Humidity (RH), summer is the season with the lowest mean visibility in a year. Although PM10 index was reported in a decreasing trend (Chan and Yao, 2008), the increase of RH has resulted in a decreasing trend of visibility over BCIA in the summer from 1999 to 2007. To ensure blue sky ("good" visibility) for Olympics 2008, daily mean PM10 index should have been reduced from 81 to 44. This requires that not only vehicle emissions, but also other emissions should be limited. Observations verify that blue-sky-hour rate increased significantly after mean PM10 index was reduced to 53 during Olympics 2008, however, the visibility of 2009 returned to the mean level from 1999 to 2007 during the period 8-24 August. RH (aerosol) contribute 24% (76%) of the improvement of visibility during August 2008.

  10. 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

  11. Etude sur les tendons en materiaux composites et leur application aux ancrages postcontraints

    NASA Astrophysics Data System (ADS)

    Chennouf, Adil

    L'objectif general de la presente these est d'evaluer le comportement a l'arrachement et au fluage d'ancrages injectes constitues de tendons en materiaux composites afin d'etablir des recommandations plus appropriees et realistes pour le dimensionnement et la conception. Quatre types de tendons en materiaux composites, deux a base de fibres d'aramide et deux a base de fibres de carbone, ont ete utilises dans l'etude. Les travaux de recherche de cette these ont porte notamment sur: (I) Une caracterisation physique et mecanique des tendons en materiaux composites utilises dans l'etude. (II) Une etude en laboratoire sur les coulis de scellement. La premiere etape de cette etude a concerne le developpement d'un coulis de scellement performant adapte aux tendons en materiaux composites et a differentes situations d'injection. La seconde etape a traite des essais de caracterisations physique et mecanique du coulis de scellement developpe comparativement a trois coulis de scellement usuels d'un meme rapport E/L de 0,4. (III) Une etude sur des modeles reduits d'ancrages injectes. (IV) Une etude sur des modeles d'ancrages a grande echelle. La synthese de ces etudes a permis d'enoncer les principales conclusions suivantes: (1) Les valeurs moyennes des charges de rupture des tendons en materiaux composites ont ete de 1% a 29% superieures a celles specifiees par les manufacturiers. (2) L'etude sur les coulis de scellement a permis le developpement de coulis de ciment repondant aux criteres fixes, soient une grande stabilite, une bonne fluidite, une legere expansion et de bonnes caracteristiques mecaniques. (3) Les tendons en materiaux composites ont montre des contraintes d'adherence maximum superieures a celles des tendons en acier. (4) Le type de fibre, la configuration et le fini de surface des tendons en materiaux composites gouvernent leur resistance a l'adherence. (5) L'introduction de sable et d'autres ajouts comme les fines de silice et la poudre d'aluminium au coulis

  12. Variability in UVB radiation in Beijing, China.

    PubMed

    Bo, Hu; Xinghua, Zhang; Yuesi, Wang

    2013-01-01

    The variation characteristics of Ultraviolet-B (UVB; 280-315 nm) radiation over Beijing were explored using measured data that were collected in Beijing from November 2010 to October 2011. Seasonal variations in UVB radiation and influence of ozone and clearness index on the ratio of UVB to broadband solar radiation (G) were investigated. The annual value of UVB radiation in Beijing is 6.37 MJ m(-2), and monthly average value ranges from 4.96 to 28.37 kJ m(-2) d(-1). The maximum daily total UVB radiation ranges from 6.55 kJ m(-2) d(-1) in November to 54.22 kJ m(-2) d(-1) in July. The monthly minimum of daily total UVB radiation varies from 0.5 kJ m(-2) d(-1) in February to 11.52 kJ m(-2) d(-1) in July. The monthly average of the ratio of UVB radiation to G ranges from 0.007 to 0.017%, with an annual average value of 0.012%. The variation in slant ozone column causes annual cycle of the ratio UVB radiation to G, with maximum value in summer. In addition, clouds have a greater effect on G than UVB radiation. Thus, the ratio increases by more than 17% when the atmospheric conditions change from clear to cloudy.

  13. Transmission of Mycobacterium tuberculosis Beijing Strains, Alberta, Canada, 1991-2007.

    PubMed

    Langlois-Klassen, Deanne; Senthilselvan, Ambikaipakan; Chui, Linda; Kunimoto, Dennis; Saunders, L Duncan; Menzies, Dick; Long, Richard

    2013-05-01

    Beijing strains are speculated to have a selective advantage over other Mycobacterium tuberculosis strains because of increased transmissibility and virulence. In Alberta, a province of Canada that receives a large number of immigrants, we conducted a population-based study to determine whether Beijing strains were associated with increased transmission leading to disease compared with non-Beijing strains. Beijing strains accounted for 258 (19%) of 1,379 pulmonary tuberculosis cases in 1991-2007; overall, 21% of Beijing cases and 37% of non-Beijing cases were associated with transmission clusters. Beijing index cases had significantly fewer secondary cases within 2 years than did non-Beijing cases, but this difference disappeared after adjustment for demographic characteristics, infectiousness, and M. tuberculosis lineage. In a province that has effective tuberculosis control, transmission of Beijing strains posed no more of a public health threat than did non-Beijing strains.

  14. 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.

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

    SciTech Connect

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

    2009-02-15

    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 {mu} g g{sup -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.

  16. 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

  17. Synthese et utilisation de fibres cellulosiques phosphatees pour la valorisation de la fibre vegetale dans l'amelioration des proprietes de surface du papier et la fabrication de materiaux ignifuges

    NASA Astrophysics Data System (ADS)

    Lentsolo Yalli, Gym Clerc

    Dans cette etude, nous souhaitions principalement greffer des groupements phosphates directement sur la cellulose comme materiau modele, et par la suite transposer les conditions optimales du design concu pour la cellulose, determine par modelisation a l'aide de l'outil JMP, sur la pate kraft. Ensuite, evaluer les proprietes physico-chimiques, optiques, d'hydrophilie, thermiques et d'inflammabilite des materiaux fabriques (feuilles ou pastilles fabriquees) a partir des fibres phosphorylees. Pour ce faire, nous avons pretraite la cellulose et la pate kraft dans une solution aqueuse de 10 a 15 % de LiCl a 70°C pendant 7 heures. Par la suite, nous avons procede a la reaction de phosphorylation in situ avec l'acide phosphorique et l'uree, dans des conditions de temperatures et de reactifs decrites par un design experimental, pendant 3 heures. La reaction de phosphorylation s'est realisee avec succes pour l'ensemble des resultats sur la cellulose, avec des taux de greffage variables selon les conditions operatoires. Les degres de substitutions (DSP), determines par ICP-OES, et les degres de polymerisation (DP), determines par viscosimetrie, etaient aussi variables, selon les conditions. L'etude des parametres experimentaux a permis de determiner les conditions optimales transposables sur la pate kraft (DSP = 1,47 et DP = 142,42 pour la cellulose, qui represente un taux de coupure de 38% de la fibre) et les facteurs critiques de la reaction. Les resultats de la reaction sur la fibre ont permis, non seulement de constater que les conditions utilisees pour la cellulose n'etaient directement transposables a la fibre, mais permettaient quand d'obtenir un DSP interessant ≥ a 1 avec un taux de coupure de 50 a 60 %. La structure du produit principal de la reaction (le sel de calcium du pyrophosphate d'ester de cellulose ou de pate kraft) a ete determinee par les analyses FTIR, XPS, RMN-13C et RMN-31P. L'etude de l'effet de la reaction de phosphorylation sur les proprietes

  18. A model of Beijing drivers' scrambling behaviors.

    PubMed

    Shi, Jing; Bai, Yun; Tao, Li; Atchley, Paul

    2011-07-01

    A major, but unstudied, cause of crashes in China is drivers that "scramble" to gain the right of way in violation of traffic regulations. The motivation of this study is to explore the features of drivers' scrambling behaviors and the attitudes and driving skills that influence them. In this study, we established a scrambling behavior scale, and developed a driving attitude scale and a driving skill scale using factor analysis of an Internet survey of 486 drivers in Beijing. A structural equation model of scrambling behavior toward cars and pedestrians/cyclists was developed with attitudes and skills as predictors of behavior. Skills and attitudes of approval toward violations of traffic rules did not predict scrambling behaviors, while the motivation for safety and attitudes against violating traffic rules led to reduced scrambling behaviors. The current work highlights this peculiar aspect of Chinese roads and suggests methods to reduce the behavior.

  19. Seoul virus in patients and rodents from Beijing, China.

    PubMed

    Zuo, Shu-qing; Zhang, Pan-he; Jiang, Jia-fu; Zhan, Lin; Wu, Xiao-ming; Zhao, Wen-juan; Wang, Ri-min; Tang, Fang; Dun, Zhe; Cao, Wu-chun

    2008-05-01

    Hemorrhagic fever with renal syndrome (HFRS) is a significant public health problem with an increasing incidence in Beijing, China (report of disease surveillance from the Center for Disease Control and Prevention of Beijing, China). Hantaviruses were detected using RT-PCR method in blood samples of HFRS patients and lung tissues of rodents captured in Beijing. Phylogenetic analyses of 724bp partial S segment of the hantavirus gene showed that the detected Seoul virus (SEOV) fell into three different lineages, two of which circulated in Beijing. A nucleotide sequence identity of 99.7% for one of the cases of HFRS--the human- and Rattus norvegicus-originated SEOV sequences--had only two silent substitutions, suggesting genetic analysis is an essential tool for "case-investigation."

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. 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

  5. [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.

  6. Beijing moves to curb population growth.

    PubMed

    Pao, T K

    Education and incentives are being used to encourage a "one-child for one-family" campaign in Beijing. The goal is to reduce its population growth rate to 5%/1000 by 1985. Parents who have only child will receive a certificate entitling the only child to preferential treatment for nursery or kindergarten and medical care. 1-child families will receive an annual bonus of 60 yuan. Those who have more than 2 children will be taxed a minimum of 10% of salaries. Single, childless people will receive their full salaries as pensions on retirement. All urban families will receive the same housing space no matter what size the family. The same will be true for the size of small plots of land parcelled out for private use in the rural suburban area. Sterilization operations are available for those who wish them. Parents with 1 child who have such operations can have their tubes rejoined free of charge if their child is disabled or dies. The average growth rate for China projected for 1978-1000 is 1.2%.

  7. Double sodium layers observation over Beijing, China

    NASA Astrophysics Data System (ADS)

    Wang, Jihong; Yang, Yong; Cheng, Xuewu; Yang, Guotao; Song, Shalei; Gong, Shunsheng

    2012-08-01

    The altitude of the sodium layer in the mesosphere and lower thermosphere is usually from 80 km to 105 km. In this paper, we report a set of double sodium layer (DSL) events observed by sodium lidar over Beijing, China. In these DSL events, the normal sodium layer and secondary sodium layer (SeSL) present separately. There were about 17 DSL events occurred in 319 observation nights during 2009˜2011. All DSL events were observed in spring and summer. The SeSL appeared independently within the altitude range from 105 km to 130 km. The density of the SeSL is very high. The maximum ratio of peak density and the ratio of column density for the SeSL to the normal sodium layer are up to ˜60% and ˜47%, respectively. The SeSL lasted several hours, and then merged into the normal sodium layer. After the SeSL, a sporadic sodium layer occurred in the normal sodium layer.

  8. 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.

  9. 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

  10. 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

  11. 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…

  12. 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,…

  13. [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.

  14. 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.

  15. 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.

  16. Methods on defining the urban fringe area of Beijing

    NASA Astrophysics Data System (ADS)

    Wang, Xiulan; Li, Xuerui; Feng, Zhongke; Fang, Yuan

    2009-09-01

    Urban fringe lies in the transitional region between urban area and rural area. Defining the urban fringe area and researching the changing situation will be beneficial to the urban planning and the readjustment of land use structure. Taking Land-Sat TM images as basic information, using the theories of Shannon entropy and land use degree comprehensive index, methods on how to define the urban fringe area of Beijing are discussed. Further, the urban fringe area of Beijing is defined by using these two methods. It shows that the urban fringe area in Beijing includes a part of the urban district and also a small part of rural district. Distributing ring, it extends around irregularly, especially northwest and southeast.

  17. Methods on defining the urban fringe area of Beijing

    NASA Astrophysics Data System (ADS)

    Wang, Xiulan; Li, Xuerui; Feng, Zhongke; Fang, Yuan

    2010-11-01

    Urban fringe lies in the transitional region between urban area and rural area. Defining the urban fringe area and researching the changing situation will be beneficial to the urban planning and the readjustment of land use structure. Taking Land-Sat TM images as basic information, using the theories of Shannon entropy and land use degree comprehensive index, methods on how to define the urban fringe area of Beijing are discussed. Further, the urban fringe area of Beijing is defined by using these two methods. It shows that the urban fringe area in Beijing includes a part of the urban district and also a small part of rural district. Distributing ring, it extends around irregularly, especially northwest and southeast.

  18. 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.

  19. Source apportionment of ambient volatile organic compounds in Beijing.

    PubMed

    Song, Yu; Shao, Min; Liu, Ying; Lu, Sihua; Kuster, William; Goldan, Paul; Xie, Shaodong

    2007-06-15

    The ambient air quality standard for ozone is frequently exceeded in Beijing in summer and autumn. Source apportionments of volatile organic compounds (VOCs), which are precursors of ground-level ozone formation, can be helpful to the further study of tropospheric ozone formation. In this study, ambient concentrations of VOCs were continuously measured with a time resolution of 30 min in August 2005 in Beijing. By using positive matrix factorization (PMF), eight sources for the selected VOC species were extracted. Gasoline-related emissions (the combination of gasoline exhaust and gas vapor), petrochemicals, and liquefied petroleum gas (LPG) contributed 52, 20, and 11%, respectively, to total ambient VOCs. VOC emissions from natural gas (5%), painting (5%), diesel vehicles (3%), and biogenic emissions (2%) were also identified. The gasoline-related, petrochemical, and biogenic sources were estimated to be the major contributors to ozone formation potentials in Beijing. PMID:17626435

  20. 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.

  1. 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…

  2. 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…

  3. 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…

  4. [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.

  5. Thinking Styles of Primary School Teachers in Beijing, China

    ERIC Educational Resources Information Center

    Wang, Ying; Pang, Nicholas Sun-Keung

    2013-01-01

    Previous studies on teachers' thinking have usually related to teaching and learning, and concentrated on classroom-level outcomes. In this study, an organizational and administrative perspective was adopted in examining teachers' thinking style. Data collected were from a sample of 268 in-service teachers from 6 primary schools in Beijing, China.…

  6. 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…

  7. 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.

  8. 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.

  9. 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…

  10. 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

  11. 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.

  12. 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

  13. Atmospheric Particulate Matter Pollution During The 2008 Beijing Olympics

    NASA Astrophysics Data System (ADS)

    Wang, W.; Primbs, T.; Tao, S.; Zhu, T.; Simonich, S. M.

    2009-05-01

    To assess the particulate matter (PM) pollution during the 2008 Beijing Olympic games, size fractionated PM samples of >PM10, PM2.5-PM10, and Beijing for a 2 week time period prior to the Olympics, during the 2 week period of the Olympics, and for a 4 week time period following the Olympics. These time periods included 6 weeks with source control and 2 weeks without source control measures. Our SumPM10 (PM2.5-PM10 + Beijing Environmental Protection Bureau's PM10 concentrations at near-by sites. The mean Beijing were attributed to source regions located south of Beijing, including Tianjin municipality and Hebei, Shanxi and Shandong provinces, while low PM concentration in Beijing were attributed to source regions located Northwest of Beijing, including Russia and Mongolia. While meteorological parameters (air masses from the south and precipitation) accounted for 40% of the total variation in SumPM10 concentration, source control accounted for 16%, suggesting that meteorology accounted for more of the variation in PM concentration than source control measures. Based on our

  14. 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.

  15. 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.

  16. Three cases giant panda attack on human at Beijing Zoo.

    PubMed

    Zhang, Peixun; Wang, Tianbing; Xiong, Jian; Xue, Feng; Xu, Hailin; Chen, Jianhai; Zhang, Dianying; Fu, Zhongguo; Jiang, Baoguo

    2014-01-01

    Panda is regarded as Chinese national treasure. Most people always thought they were cute and just ate bamboo and had never imagined a panda could be vicious. Giant panda attacks on human are rare. There, we present three cases of giant panda attacks on humans at the Panda House at Beijing Zoo from September 2006 to June 2009 to warn people of the giant panda's potentially dangerous behavior.

  17. 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

  18. 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

  19. Three cases giant panda attack on human at Beijing Zoo

    PubMed Central

    Zhang, Peixun; Wang, Tianbing; Xiong, Jian; Xue, Feng; Xu, Hailin; Chen, Jianhai; Zhang, Dianying; Fu, Zhongguo; Jiang, Baoguo

    2014-01-01

    Panda is regarded as Chinese national treasure. Most people always thought they were cute and just ate bamboo and had never imagined a panda could be vicious. Giant panda attacks on human are rare. There, we present three cases of giant panda attacks on humans at the Panda House at Beijing Zoo from September 2006 to June 2009 to warn people of the giant panda’s potentially dangerous behavior. PMID:25550978

  20. Atmospheric particulate matter pollution during the 2008 Beijing Olympics.

    PubMed

    Wang, Wentao; Primbs, Toby; Tao, Shu; Simonich, Staci L Massey

    2009-07-15

    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 nonsource control periods. 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 nonsource 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-h guideline 100% and 81% of the time, respectively. Finally, the PM10 concentrations in October, November, and December 2008 were reduced by 9-27% 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

  1. 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

  2. [Risk assessment of quaternary groundwater contamination in Beijing Plain].

    PubMed

    Guo, Gao-Xuan; Li, Yu; Xu, Liang; Li, Zhi-Ping; Yang, Qing; Xu, Miao-Juan

    2014-02-01

    Firstly, advances in investigation and evaluation of groundwater pollution in China in the last decade were presented, and several issues in the field which hinder the development of groundwater environment were pointed out. Then, four key concepts in risk assessment of groundwater pollution were briefly described with more emphasis on the difference between groundwater pollution assessment and groundwater quality assessment in this paper. After that, a method on risk assessment of groundwater pollution which included four indicators, the pollution assessment, the quality assessment, the vulnerability and the pollution load of groundwater, was presented based on the regional characteristics of Beijing Plain. Also, AHP and expert scoring method were applied to determine the weight of the four evaluation factors. Finally, the application of this method in Beijing Plain showed the area with high, relative high, medium, relative low and low risk of groundwater contamination was 1 232.1 km2, 699.3 km2, 1 951.4 km, 2 644 km2, and 133.2 km2, respectively. The study results showed that the higher risk in the western region was likely caused by the higher pollution load and its higher vulnerability, while the relatively high risk in the southeast of Beijing plain area, the Tongzhou District, is mainly caused by historical pollution sources.

  3. 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

  4. 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.

  5. Municipal solid waste management in Beijing: characteristics and challenges.

    PubMed

    Wang, Hao; Wang, Chunmei

    2013-01-01

    An overview of the municipal solid waste (MSW) management in Beijing, a city with a resident population of about 19.61 million in 2010, is presented in the article. Economic development and population growth have resulted in a MSW generation increase from 2.96 million tons in 2000 to 6.20 million tons in 2007, fluctuating to 6.35 million tons in 2010. The components of MSW over the past decade are characterized by increasing food and paper contents, and a decreasing ash content. The percentage of food waste, the main putrescible component, increased steadily from 45.77% in 2002 to 66.98% in 2010. Combustible materials, such as plastic, paper, textile, wood and food waste, accounted for 94.66% of MSW in 2008. There are 15 landfill sites, 2 incinerators and 2 composting plants in Beijing, with a total designed capacity of 15,380 tons/day in 2010. The main waste disposal technology used in Beijing is landfill, which accounts for 92.27% of the total designed capacity in 2008 and 78.54% in 2009. The designed capacity of the existing disposal plants cannot cope with the actual quantity of waste generation, resulting in overloading and premature closure of landfill sites. Solid waste incineration has been given priority in technology development and financial support over other disposal methods. PMID:23188712

  6. [Effects of synoptic type on surface ozone pollution in Beijing].

    PubMed

    Tang, Gui-qian; Li, Xin; Wang, Xiao-ke; Xin, Jin-yuan; Hu, Bo; Wang, Li-li; Ren, Yu-fen; Wang, Yue-Si

    2010-03-01

    Ozone (O), influenced by meteorological factors, is a primary gaseous photochemical pollutant during summer to fall in Beijing' s urban ambient. Continuous monitoring during July to September in 2008 was carried out at four sites in Beijing. Analyzed with synoptic type, the results show that the ratios of pre-low cylonic (mainly Mongolia cyclone) and pre-high anticylonic to total weather conditions are about 42% and 20%, illustrating the high-and low-ozone episodes, respectively. At the pre-low cylonic conditions, high temperature, low humidity, mountain and valley winds caused by local circulation induce average hourly maximum ozone concentration (volume fraction) up to 102.2 x 10(-9), negative correlated with atmospheric pressure with a slope of -3.4 x 10(-9) Pa(-1). The time of mountain wind changed to valley wind dominates the diurnal time of maximum ozone, generally around 14:00. At the pre-high anticylonic conditions, low temperature, high humidity and systematic north wind induce average hourly maximum ozone concentration (volume fraction) only 49.3 x 10(-9), the diurnal time of maximum ozone is deferred by continuous north wind till about 16:00. The consistency of photochemical pollution in Beijing region shows that good correlation exists between synoptic type and ozone concentration. Therefore, getting an eye on the structure and evolution of synoptic type is of great significances for forecasting the photochemical pollution.

  7. [Characteristics of chemical compositions of precipitation in Beijing].

    PubMed

    Yang, Dong-Yan; Li, Xiu-Jinz; Chen, Yuan-Yuan; Zou, Ben-Dong; Lin, An-Guo

    2011-07-01

    Characteristics of chemical compositions of precipitation in Beijing were analyzed. The average value of pH was 5.19 from 2005 to 2009, showing stable characteristics of acidification with precipitation. The lowest annual average pH was 4. 87 in 2008 with the highest acidification frequency of 42% and 23% in Chegongzhuang and Daxing districts respectively. The inorganic ion concentrations declined in 5a, indicating an increasing improvement of air quality in Beijing. The concentrations of NH4+ and NO3- were found to increase and contributed to the high nitrogen amount in precipitation. Different seasons have influence on composition concentrations. Generally speaking, the ion concentrations in winter were higher that that in summer. SO4(2-) was the main factor responsible for the acidification of snow in winter, SO4(2-) and NO3- had similar contributions to the acidification of precipitation in summer. It was also found that the local pollutants of SO2, NO(x) and NH3 were major contributors to the acidification of precipitation in Beijing area, local geological conditions and long-distance transfers have important effects on the neutralization of the precipitation.

  8. 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.

  9. [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

  10. Municipal solid waste management in Beijing: characteristics and challenges.

    PubMed

    Wang, Hao; Wang, Chunmei

    2013-01-01

    An overview of the municipal solid waste (MSW) management in Beijing, a city with a resident population of about 19.61 million in 2010, is presented in the article. Economic development and population growth have resulted in a MSW generation increase from 2.96 million tons in 2000 to 6.20 million tons in 2007, fluctuating to 6.35 million tons in 2010. The components of MSW over the past decade are characterized by increasing food and paper contents, and a decreasing ash content. The percentage of food waste, the main putrescible component, increased steadily from 45.77% in 2002 to 66.98% in 2010. Combustible materials, such as plastic, paper, textile, wood and food waste, accounted for 94.66% of MSW in 2008. There are 15 landfill sites, 2 incinerators and 2 composting plants in Beijing, with a total designed capacity of 15,380 tons/day in 2010. The main waste disposal technology used in Beijing is landfill, which accounts for 92.27% of the total designed capacity in 2008 and 78.54% in 2009. The designed capacity of the existing disposal plants cannot cope with the actual quantity of waste generation, resulting in overloading and premature closure of landfill sites. Solid waste incineration has been given priority in technology development and financial support over other disposal methods.

  11. "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

  12. [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.

  13. Etude de l'affaiblissement du comportement mecanique du pergelisol du au rechauffement climatique

    NASA Astrophysics Data System (ADS)

    Buteau, Sylvie

    Le rechauffement climatique predit pour les prochaines decennies, aura des impacts majeurs sur le pergelisol qui sont tres peu documentes pour l'instant. La presente etude a pour but d'evaluer ces impacts sur les proprietes mecaniques du pergelisol et sa stabilite a long terme. Une nouvelle technique d'essai de penetration au cone a taux de deformation controle, a ete developpee pour caracteriser en place le pergelisol. Ces essais geotechniques et la mesure de differentes proprietes physiques ont ete effectues sur une butte de pergelisol au cours du printemps 2000. Le developpement et l'utilisation d'un modele geothermique 1D tenant compte de la thermodependance du comportement mecanique ont permis d'evaluer que les etendues de pergelisol chaud deviendraient instables a la suite d'un rechauffement de l'ordre de 5°C sur cent ans. En effet, la resistance mecanique du pergelisol diminuera alors rapidement jusqu'a 11,6 MPa, ce qui correspond a une perte relative de 98% de la resistance par rapport a un scenario sans rechauffement.

  14. 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

  15. Etude des etats electroniques en champ magnetique dans le niveau de Landau N=0 de la tricouche ABC de graphene

    NASA Astrophysics Data System (ADS)

    Rondeau, Maxime

    Dans cet ouvrage nous etudions les phases du gaz d'electrons bidimensionnel dans la tricouche de graphene en empilement ABC. En partant du modele des liaisons fortes et en faisant l'approximation du continuum autour des vallees K +, K-, nous obtenons un modele effectif a deux bandes qui permet de decrire la physique de basse energie des electrons en champ magnetique dans cette structure. Ce modele contient trois orbitales degenerees dans le niveau de Landau N = O. Ce dernier est donc 12N φ, fois degeneres en incluant les degres de liberte de spin et de vallee. En ajoutant l'interaction de Coulomb au systeme et en considerant seulement les remplissages v = -5, -4, -4, 5 afin d'avoir un systeme a trois niveaux, nous etudions le diagramme de phase du gaz d'electrons en fonction d'un biais electrique entre les couches externes. Nous trouvons une phase d'onde de densite de charge bidimensionnelle (ODC2D) comme etat fondamental du systeme. Cette ODC2D se nomme cristal dans ce memoire et nous derivons ses proprietes de transports et ses modes collectifs. Nous discutons egalement du caractere topologique de ce cristal. Notre etude englobe aussi les phases liquides avec ou sans coherence orbitale. Nous concluons notre memoire par l'etude de quelques signatures experimentales des phases du gaz d'electrons dans la tricouche.

  16. 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…

  17. 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…

  18. 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 =…

  19. 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…

  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. 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.

  2. 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

  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.

  4. 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

  5. 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.

  6. Etude de la dynamique des porteurs dans des nanofils de silicium par spectroscopie terahertz

    NASA Astrophysics Data System (ADS)

    Beaudoin, Alexandre

    Ce memoire presente une etude des proprietes de conduction electrique et de la dynamique temporelle des porteurs de charges dans des nanofils de silicium sondes par rayonnement terahertz. Les cas de nanofils de silicium non intentionnellement dopes et dopes type n sont compares pour differentes configurations du montage experimental. Les mesures de spectroscopie terahertz en transmission montre qu'il est possible de detecter la presence de dopants dans les nanofils via leur absorption du rayonnement terahertz (˜ 1--12 meV). Les difficultes de modelisation de la transmission d'une impulsion electromagnetique dans un systeme de nanofils sont egalement discutees. La detection differentielle, une modification au systeme de spectroscopie terahertz, est testee et ses performances sont comparees au montage de caracterisation standard. Les instructions et des recommendations pour la mise en place de ce type de mesure sont incluses. Les resultats d'une experience de pompe optique-sonde terahertz sont egalement presentes. Dans cette experience, les porteurs de charge temporairement crees suite a l'absorption de la pompe optique (lambda ˜ 800 nm) dans les nanofils (les photoporteurs) s'ajoutent aux porteurs initialement presents et augmentent done l'absorption du rayonnement terahertz. Premierement, l'anisotropie de l'absorption terahertz et de la pompe optique par les nanofils est demontree. Deuxiemement, le temps de recombinaison des photoporteurs est etudie en fonction du nombre de photoporteurs injectes. Une hypothese expliquant les comportements observes pour les nanofils non-dopes et dopes-n est presentee. Troisiemement, la photoconductivite est extraite pour les nanofils non-dopes et dopes-n sur une plage de 0.5 a 2 THz. Un lissage sur la photoconductivite permet d'estimer le nombre de dopants dans les nanofils dopes-n. Mots-cles: nanofil, silicium, terahertz, conductivite, spectroscopie, photoconductivite.

  7. Investigation on Mycobacterium tuberculosis Diversity in China and the Origin of the Beijing Clade

    PubMed Central

    Wan, Kanglin; Liu, Jinghua; Hauck, Yolande; Zhang, Yuanyuan; Liu, Jie; Zhao, Xiuqin; Liu, Zhiguang; Lu, Bing; Dong, Haiyan; Jiang, Yi; Kremer, Kristin; Vergnaud, Gilles; van Soolingen, Dick; Pourcel, Christine

    2011-01-01

    Background Investigation of the genetic diversity of Mycobacterium tuberculosis in China has shown that Beijing genotype strains play a dominant role in the tuberculosis (TB) epidemic. In order to examine the strain diversity in the whole country, and to study the evolutionary development of Beijing strains, we sought to genotype a large collection of isolates using different methods. Methodology/Principal Findings We applied a 15-loci VNTR typing analysis on 1,586 isolates from the Beijing municipality and 12 Chinese provinces or autonomous regions. The data was compared to that of 900 isolates from various other worldwide geographic regions outside of China. A total of 1,162/1,586 (73.2%) of the isolates, distributed into 472 VNTR types, were found to belong to the Beijing genotype family and this represented 56 to 94% of the isolates in each of the localizations. VNTR typing revealed that the majority of the non-Beijing isolates fall into two genotype families, which represented 17% of the total number of isolates, and seem largely restricted to China. A small number of East African Indian genotype strains was also observed in this collection. Ancient Beijing strains with an intact region of difference (RD) 181, as well as strains presumably resembling ancestors of the whole Beijing genotype family, were mainly found in the Guangxi autonomous region. Conclusions/Significance This is the largest M. tuberculosis VNTR-based genotyping study performed in China to date. The high percentage of Beijing isolates in the whole country and the presence in the South of strains representing early branching points may be an indication that the Beijing lineage originated from China, probably in the Guangxi region. Two modern lineages are shown here to represent the majority of non-Beijing Chinese isolates. The observed geographic distribution of the different lineages within China suggests that natural frontiers are major factors in their diffusion. PMID:22220207

  8. 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

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

    PubMed

    Hao, Jiming; Wang, Litao

    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 (SO2), 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 SO2 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.

  10. 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.

  11. Vertical ozone characteristics in urban boundary layer in Beijing.

    PubMed

    Ma, Zhiqiang; Xu, Honghui; Meng, Wei; Zhang, Xiaoling; Xu, Jing; Liu, Quan; Wang, Yuesi

    2013-07-01

    Vertical ozone and meteorological parameters were measured by tethered balloon in the boundary layer in the summer of 2009 in Beijing, China. A total of 77 tethersonde soundings were taken during the 27-day campaign. The surface ozone concentrations measured by ozonesondes and TEI 49C showed good agreement, albeit with temporal difference between the two instruments. Two case studies of nocturnal secondary ozone maxima are discussed in detail. The development of the low-level jet played a critical role leading to the observed ozone peak concentrations in nocturnal boundary layer (NBL). The maximum of surface ozone was 161.7 ppbv during the campaign, which could be attributed to abundant precursors storage near surface layer at nighttime. Vertical distribution of ozone was also measured utilizing conventional continuous analyzers on 325-m meteorological observation tower. The results showed the NBL height was between 47 and 280 m, which were consistent with the balloon data. Southerly air flow could bring ozone-rich air to Beijing, and the ozone concentrations exceeded the China's hourly ozone standard (approximately 100 ppb) above 600 m for more than 12 h.

  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. Beijing Basin's amplification effect on long-period ground motion

    NASA Astrophysics Data System (ADS)

    Fu, Changhua

    2016-04-01

    A lot of high-rise buildings are located in basins. Previous researches tell us that the intensity of long-period ground motion in the basin is usually larger than that in its vicinities when a strong earthquake occurs. This higher intensity will cause severe damage to high-rise buildings which have long self-vibrating periods. So, by studying the characteristics of ground motion in the basin and analyzing basin amplification effect on long-period ground motion, we can understand reasonable seismic fortification requirement of high-rise buildings in the basin, and provide scientific reference for city future planning, earthquake emergency and rescue. Taking Beijing Basin as an example, we set up several scenario earthquakes, then use Ground-Motion-Simulation method to study how different scenario earthquakes influence basin's amplification effect on long-period ground motion. The research demonstrates that the amplification effect on 3~10-second ground motion acceleration response spectrum is mainly controlled by thickness of sediment in basin, although different seismic sources may cause the uncertainty to a certain extent. Thus, the average basin's amplification factor on 3~10-second ground motion acceleration response spectrum is computed, and the correlation function, that between the average amplification factor and equivalent thickness of sediment in basin, is analyzed. Finally, according to the distribution of high-rise buildings in Beijing Basin, preliminary discussion on the relationship between risk level of seismic hazard of high-rise buildings and basin structure is made.

  14. [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.

  15. [Relationship between surface UV radiation and air pollution in Beijing].

    PubMed

    An, Jun-lin; Wang, Yue-si; Li, Xin; Sun, Yang; Shen, Shuang-he

    2008-04-01

    Based on the data of solar radiation and air pollutants collected in Beijing, the relationship between surface ultraviolet (UV) radiation and the content of air pollutants were analyzed, using the radiative transfer model TUV4.4 (Tropospheric Ultraviolet Visible). The results show that average total ozone content is 329 DU and higher in winter and spring, lower in summer and autumn. The inverse relationship exists between ground level UV radiation and total ozone content. This study also shows that a substantial reduction (up to 50%) in the UV radiation on days with high levels of air pollution. Larger fluctuations are found in UV radiation in the summer. The effects of clouds and air pollution on UV are higher than on total solar radiation, and the reduction in UV is about twice as large as the total solar radiation values. Strong reduction in the UV radiation reaching the ground is associated with the increase of tropospheric ozone and nitrogen oxides in Beijing. The correlation coefficient between ozone concentration and decrease in UV radiation is 0.70 in the early afternoon.

  16. Beijing Lightning Network (BLNET): Configuration, Function and Preliminary Results

    NASA Astrophysics Data System (ADS)

    Qie, X.; Wang, D.; Wang, Y.; Liu, M.; Tian, Y.; Lu, G.

    2015-12-01

    A regional multi-frequency-band lightning detection network in Beijing (BLNET) has been developed for both research and operational purposes. The network is employed in the experiment of Dynamic-microphysical-electrical Processes in Severe Thunderstorms and Lightning Hazards (Storm973), supported by Ministry of Science and Technology as National Key Basic Research Program of China or 973 Program. The network consisted of 16 stations in 2015 covering most part of The "Jing-Jin-Ji" (Beijing-Tianjin-Hebei) metropolis zone, one of the most developed areas in China. Four different sensors, including slow antenna, fast antenna, magnetic antenna, and VHF antenna, are integrated in each station to detect lightning radiation signals in different frequency band. The Chan algorithm and Levenberg-Marquardt method are adopted jointly in the lightning location algorithm. In addition to locate the lightning radiation pulses in two-dimension or three-dimension in different band, the charge source neutralized by the lightning discharge can be retrieved either. The theoretical horizontal error over the network is less than 200 m and the vertical error is less than 500 m over the network. The comparison of total lightning location results with corresponding radar echoes for thunderstorm cases indicates the good performance of BLNET in the severe convection surveillance. The actual two-dimensional location error in VLF/LF band, compared with a ground truth that acquired with a GPS-synchronized high-speed video camera, is about 250 m.

  17. 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.

  18. [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

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. Genetic diversity and transmission characteristics of Beijing family strains of Mycobacterium tuberculosis in Peru.

    PubMed

    Iwamoto, Tomotada; Grandjean, Louis; Arikawa, Kentaro; Nakanishi, Noriko; Caviedes, Luz; Coronel, Jorge; Sheen, Patricia; Wada, Takayuki; Taype, Carmen A; Shaw, Marie-Anne; Moore, David A J; Gilman, Robert H

    2012-01-01

    Beijing family strains of Mycobacterium tuberculosis have attracted worldwide attention because of their wide geographical distribution and global emergence. Peru, which has a historical relationship with East Asia, is considered to be a hotspot for Beijing family strains in South America. We aimed to unveil the genetic diversity and transmission characteristics of the Beijing strains in Peru. A total of 200 Beijing family strains were identified from 2140 M. tuberculosis isolates obtained in Lima, Peru, between December 2008 and January 2010. Of them, 198 strains were classified into sublineages, on the basis of 10 sets of single nucleotide polymorphisms (SNPs). They were also subjected to variable number tandem-repeat (VNTR) typing using an international standard set of 15 loci (15-MIRU-VNTR) plus 9 additional loci optimized for Beijing strains. An additional 70 Beijing family strains, isolated between 1999 and 2006 in Lima, were also analyzed in order to make a longitudinal comparison. The Beijing family was the third largest spoligotyping clade in Peru. Its population structure, by SNP typing, was characterized by a high frequency of Sequence Type 10 (ST10), which belongs to a modern subfamily of Beijing strains (178/198, 89.9%). Twelve strains belonged to the ancient subfamily (ST3 [n=3], ST25 [n=1], ST19 [n=8]). Overall, the polymorphic information content for each of the 24 loci values was low. The 24 loci VNTR showed a high clustering rate (80.3%) and a high recent transmission index (RTI(n-1)=0.707). These strongly suggest the active and on-going transmission of Beijing family strains in the survey area. Notably, 1 VNTR genotype was found to account for 43.9% of the strains. Comparisons with data from East Asia suggested the genotype emerged as a uniquely endemic clone in Peru. A longitudinal comparison revealed the genotype was present in Lima by 1999.

  4. 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

  5. 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

  6. Double sodium layer observation over Beijing, China by lidar

    NASA Astrophysics Data System (ADS)

    Wang, Jihong; Yang, Guotao; Yong, Yang; Song, Shalei; Gong, Shunsheng; Cheng, Xuewu

    2012-07-01

    The sodium layer is usually located between 80-105 km. The double sodium layer (DSL) event observed by sodium lidar (light detection and radar) over Wuhan extend the altitude to about 125km. A secondary sodium layer appeared above the normal sodium layer. However, the exact mechanism responsible for the DSL formation is still unclear, due to lack of DSL events observed. In this paper, we reports a series of double sodium layer events observed by sodium lidar over Beijing, China. About ten DSL events occurred during 2010 and 2011. All DSL events were observed in summer. The SeSL last about several hours and joined the normal sodium layer, which seems its loss mechanism. When the SeSL disappeared, the sporadic sodium layer occurred in the normal sodium layer.

  7. [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

  8. 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

  9. [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.

  10. [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

  11. [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.

  12. 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.

  13. 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.

  14. Examine Urban Extreme Rainfall Event: A Case Study for Beijing 7.13.2012 Event

    NASA Astrophysics Data System (ADS)

    Jin, M.; Li, Y.; Shepherd, M.; Su, D.

    2013-05-01

    Using satellite remote sensing observations from 1 km MODIS data, this paper examines the clouds, aerosols, water vapor and surface skin temperature over Beijing to understand the heat and hydrological conditions responsible for the extreme rainfall event that occurred in Beijing on July 21, 2012. Remote sensing data, with the advantage of high spatial resolution and coverage, proves three key mechanisms: (a) the urban heat island effect (UHI) may have contributed to strong convection over Beijing, which led to high level cloud cover; (b) urban aerosol amount peaked before the rainfall, which may have "seeded" the clouds and invigorating precipitation; and (c) abundant water vapor was transported from the northwest into Beijing region and enhanced the existing rainfall system. Simply put, the urban canyon effect, aerosol effect, and UHI effect all likely contributed to enhancement of this extreme rainfall. This work proves that urban system is responsible, at least partly, for urban rainfall extremes.;

  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. 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.

  17. 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

  18. Phylogenetic assignment of Mycobacterium tuberculosis Beijing clinical isolates in Japan by maximum a posteriori estimation.

    PubMed

    Seto, Junji; Wada, Takayuki; Iwamoto, Tomotada; Tamaru, Aki; Maeda, Shinji; Yamamoto, Kaori; Hase, Atsushi; Murakami, Koichi; Maeda, Eriko; Oishi, Akira; Migita, Yuji; Yamamoto, Taro; Ahiko, Tadayuki

    2015-10-01

    Intra-species phylogeny of Mycobacterium tuberculosis has been regarded as a clue to estimate its potential risk to develop drug-resistance and various epidemiological tendencies. Genotypic characterization of variable number of tandem repeats (VNTR), a standard tool to ascertain transmission routes, has been improving as a public health effort, but determining phylogenetic information from those efforts alone is difficult. We present a platform based on maximum a posteriori (MAP) estimation to estimate phylogenetic information for M. tuberculosis clinical isolates from individual profiles of VNTR types. This study used 1245 M. tuberculosis clinical isolates obtained throughout Japan for construction of an MAP estimation formula. Two MAP estimation formulae, classification of Beijing family and other lineages, and classification of five Beijing sublineages (ST11/26, STK, ST3, and ST25/19 belonging to the ancient Beijing subfamily and modern Beijing subfamily), were created based on 24 loci VNTR (24Beijing-VNTR) profiles and phylogenetic information of the isolates. Recursive estimation based on the formulae showed high concordance with their authentic phylogeny by multi-locus sequence typing (MLST) of the isolates. The formulae might further support phylogenetic estimation of the Beijing lineage M. tuberculosis from the VNTR genotype with various geographic backgrounds. These results suggest that MAP estimation can function as a reliable probabilistic process to append phylogenetic information to VNTR genotypes of M. tuberculosis independently, which might improve the usage of genotyping data for control, understanding, prevention, and treatment of TB.

  19. [Research on the virtual water composition and virtual water trade for agriculture in Beijing].

    PubMed

    Wang, Hong-rui; Wang, Yan; Wang, Jun-hong; Dong, Yan-yan; Han, Zhao-xing

    2007-12-01

    Based on the irrigation norm of typical district and county, and revised by the isoline map of Chinese crops water demand, the change of crops program was analyzed as well as the agricultural water use and its GDP benefits. Then the virtual water was calculated for years. At last, the input-output method was used to calculate the trade of virtual water in Beijing. As the results, the virtual water for cereal crops has been decreasing in Beijing, from 1.832 x 10(9) m3 in 1990 to 4.283 x 10(8) m3 in 2004. Otherwise the virtual water for technical crops has been increasing, which is from 9.06 x 10(8) m3 in 1990 to 1.492 x 10(9) m3 in 2004. On the whole, the virtual water for crops has been decreasing in Beijing. From the angle of primary products Beijing is a virtual water importing area. Virtual water importing of annual average is 2.37 x 10(8) m3, which is about 5.93% of the total water of Beijing. Virtual water has been an important supplement of local real water of 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. 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.

  2. 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.

  3. 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

  4. 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

  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. 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 particles or aged

  7. 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

  8. 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

  9. 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

  10. 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

  11. Predominance of Mycobacterium tuberculosis EAI and Beijing lineages in Yangon, Myanmar.

    PubMed

    Phyu, Sabai; Stavrum, Ruth; Lwin, Thandar; Svendsen, Øyvind S; Ti, Ti; Grewal, Harleen M S

    2009-02-01

    Isolates of the Mycobacterium tuberculosis Beijing lineage are associated with high rates of transmission, hypervirulence and drug resistance. The Beijing lineage has been shown to dominate the tuberculosis (TB) epidemic in East Asia; however, the diversity and frequency of M. tuberculosis genotypes from Myanmar are unknown. We present the first comprehensive study describing the M. tuberculosis isolates circulating in Yangon, Myanmar. Thus, 310 isolates from pulmonary TB patients from Yangon, Myanmar, were genotyped by spoligotyping and IS6110-based restriction fragment length polymorphism analysis (IS6110 RFLP). The most frequent lineages observed were the East African-Indian (EAI; 48.4%; n = 150) and Beijing (31.9%; n = 99) lineages. Isolates belonging to the most frequent shared types (STs), ST1 (n = 98; Beijing), ST292 (n = 28; EAI), and ST89 (n = 11; EAI), had >or=75% similarity in their IS6110 patterns. Five of 11 Beijing isolates comprising five clusters with identical IS6110 RFLP patterns could be discriminated by mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) analysis. Of the 150 EAI isolates, 40 isolates (26.7%) had only one IS6110 copy, and 17 of these isolates could be discriminated by MIRU-VNTR analysis. The findings from this study suggest that although there is a predominance of the ancient EAI lineage in Yangon, the TB epidemic in Yangon is driven by clonal expansion of the ST1 genotype. The Beijing lineage isolates (21.4%) were more likely (P = 0.009) than EAI lineage isolates to be multidrug resistant (MDR) (1.3%; odds ratio, 3.2, adjusted for the patients' history of exposure to anti-TB drugs), suggesting that the spread of MDR Beijing isolates is a major problem in Yangon.

  12. 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.

  13. Chemical composition of rainwater and the acid neutralizing effect at Beijing and Chizhou city, China

    NASA Astrophysics Data System (ADS)

    Xu, Zhifang; Wu, Yao; Liu, Wen-Jing; Liang, Chong-Shan; Ji, Jianpeng; Zhao, Tong; Zhang, Xuan

    2015-10-01

    The chemical compositions were measured in rainwater samples collected during 2011-2012 from two representative cities, Beijing in north China and Chizhou city in south China. The rainwater was highly acidic with a volume-weighted mean (VWM) pH of 4.56, ranging from 3.77 to 5.67, and about 94% of the samples had pH below 5.0 in Chizhou. The pH values of rainwater in Beijing ranged from 3.78 to 6.62, with a VWM value of 4.85. The predominant ions in the precipitation were SO42 -, Ca2 + and NH4+ at both sites. The VWM concentrations of ions in rainwater were higher in Beijing, and the SO42 - concentration of rainwater in Beijing was about twice that in Chizhou. However, due to the weaker neutralization of acidity, the rainwater from Chizhou had relatively low pH values. According to the results of linear regression analysis, the percentage of the potential acidity counteracted by Ca2 + and NH4+ was higher in rainwater in Beijing (90.7%) than that in Chizhou (70.8%). Using Na as an indicator of marine origin, and Al for the terrestrial inputs, the proportions of sea salt and terrestrial elements were estimated from elemental ratios. More than 98% of SO42 - and Ca2 + in rainwater samples are non-sea-salt origin at both sites. Coal combustion may be the main source of SO42 -, and local and remote soil dust may be an important source of Ca2 + in Beijing rainwater. The high concentrations of alkaline ions (Ca2 + and NH4+) have played an important role to neutralize the acidity of rainwater in Beijing.

  14. 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

  15. 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.

  16. [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

  17. [Fluorescence properties of urban water bodies of Beijing].

    PubMed

    Wu, Jing; Cui, Shuo; Su, Wei; Cao, Zhi-Ping

    2011-06-01

    "Fluorescence fingerprint" of water body based on fluorescence excitation-emission matrix has been a novel and valuable method to exhibit the organics details. In the present study, the fluorescence matrixes of urban water bodies of Beijing were investigated. The experimental results showed that these matrixes could be divided into 3 groups: Type I owned two fluorescence centers, locating at lambda(ex)/lambda(em) = 275-280/340 and 225-230/340 nm respectively, and was the predominant group; fluorescence centers of Type II located at lambda(ex)/lambda(em) = 280/345-365 and 245/380 nm; Type II had four fluorescence centers around 275/305, 275/340, 225/305 and 225/340 nm. The fingerprints indicated that these water bodies had been disturbed by human activities. Type I and Type III were transitional fingerprints between undisturbed water body and sewage wastewater and Type III was closer to sewage wastewater. Type II closely originated from reclaimed water of municipal wastewater treatment plant. These three types were main types of urban water bodies where domestic pollution was dominating. The fluorescence fingerprints clearly displayed the ubiquitous impacts of human activities and the resulting potential risk. Fluorescence fingerprint could display pollution information and serve as a possible diagnosis tool of pollution source.

  18. 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

  19. [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

  20. 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.

  1. [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.

  2. [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.

  3. [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

  4. 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.

  5. [Beijing to use education, incentives to control population growth].

    PubMed

    1979-11-01

    The Beijing Municipal Family Planning Office started in 1979 a "1 child-1 family" campaign aimed at city dwellers and suburban peasants through a system of incentives for parents. The aim is to reduce China's population growth to 5/1000 by 1985. Parents who undertake to have only 1 child will receive a certificate entitling the child to preferential entrance to nursery school, kindergarten, school, factory jobs, and preferential treatment in medical care. A 1 child family will receive an annual 60 yuan bonus to be returned if the parents decide to have another child. Better housing and less taxation will also be provided for 1 child families. Childless people will receive their full wage as a pension on retirement, or will receive subsidies from their production team. A series of measures to improve maternity and child care, and sterilization operations have also been taken. An education campaign to change ideas about male superiority is presently taking place in rural areas, and young couples are recommended to move in with the bride's family.

  6. 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.

  7. Seatbelt use amongst taxi drivers in Beijing, China.

    PubMed

    Passmore, J; Ozanne-Smith, J

    2006-09-01

    Associated with explosive growth in motorization, China has the world's highest road toll with more than 100,000 deaths and 400,000 injuries annually. In response, the Chinese Government introduced the first road traffic safety law in 2003, which included mandatory use of seatbelts by drivers and front seat passengers. Noting frequent non-compliance to this seatbelt regulation by Beijing taxi drivers, the authors studied seatbelt use patterns as onboard observers in a convenience sample of 235 taxi trips. Findings indicated a low seatbelt-wearing rate among taxi drivers of 7.7%, an overt non-wearing rate of 57%, covert non-wearing of 35.3% and total non-compliance of 92.3%. As in high-income countries, adoption of proven safety strategies, including wearing safety restraints, could contribute to reducing the Chinese road toll, particularly as vehicle occupant numbers and the availability of restraints increases. Further investigation of reasons for non-compliance and pretense of wearing seatbelts is required to inform future seatbelt-wearing promotions, including attitudinal studies of taxi drivers. Seatbelt wearing rates should continue to be monitored.

  8. 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

  9. 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

  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. 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.

  12. 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.

  13. Evolutionary History and Ongoing Transmission of Phylogenetic Sublineages of Mycobacterium tuberculosis Beijing Genotype in China

    PubMed Central

    Yin, Qing-qin; Liu, Hai-can; Jiao, Wei-wei; Li, Qin-jing; Han, Rui; Tian, Jian-ling; Liu, Zhi-guang; Zhao, Xiu-qin; Li, Ying-jia; Wan, Kang-lin; Shen, A-dong; Mokrousov, Igor

    2016-01-01

    Mycobacterium tuberculosis Beijing genotype originated in China and has undergone a dramatic population growth and global spread in the last century. Here, a collection of M. tuberculosis Beijing family isolates from different provinces across all China was genotyped by high-resolution (24-MIRU-VNTR) and low-resolution, high-rank (modern and ancient sublineages) markers. The molecular profiles and global and local phylogenies were compared to the strain phenotype and patient data. The phylogeographic patterns observed in the studied collection demonstrate that large-scale (but not middle/small-scale) distance remains one of the decisive factors of the genetic divergence of M. tuberculosis populations. Analysis of diversity and network topology of the local collections appears to corroborate a recent intriguing hypothesis about Beijing genotype originating in South China. Placing our results within the Eurasian context suggested that important Russian B0/W148 and Asian/Russian A0/94-32 epidemic clones of the Beijing genotype could trace their origins to the northeastern and northwestern regions of China, respectively. The higher clustering of the modern isolates in children and lack of increased MDR rate in any sublineage suggest that not association with drug resistance but other (e.g., speculatively, virulence-related) properties underlie an enhanced dissemination of the evolutionarily recent, modern sublineage of the Beijing genotype in China. PMID:27681182

  14. Seasonal pollution characteristics of organic compounds in atmospheric fine particles in Beijing.

    PubMed

    He, Ling-Yan; Hu, Min; Huang, Xiao-Feng; Zhang, Yuan-Hang; Tang, Xiao-Yan

    2006-04-15

    Beijing is a rapidly developing city with severe and unique air pollution problems. Organic matter is the most abundant fraction in fine particles in Beijing, occupying 30-50% of the total mass, indicating its key role in air pollution control. However, detailed chemical characterization of particulate organic matter in Beijing has never been reported. In this study, fine particles in the urban atmosphere in Beijing were investigated for its organic components by GC/MS technique. Over 100 individual organic compounds were identified and quantified in 25 PM2.5 samples from the summer, autumn and winter of 2002-2003. Alkanes, fatty acids, dicarboxylic acids, polycyclic aromatic hydrocarbons and some important tracer compounds (hopanes, levoglucosan and steroids) were the major constituents with the sum of their concentrations of 502, 1471 and 1403 ng m(-3) in summer, autumn and winter, respectively. Different organic compounds presented apparently different seasonal characteristics, reflecting their different dominant emission sources, such as coal combustion, biomass burning and cooking emission. The abundance and origin of these organic compounds are discussed to reveal seasonal air pollution characteristics of Beijing.

  15. Ambient air quality and the effects of air pollutants on otolaryngology in Beijing.

    PubMed

    Zhang, Fengying; Xu, Jin; Zhang, Ziying; Meng, Haiying; Wang, Li; Lu, Jinmei; Wang, Wuyi; Krafft, Thomas

    2015-08-01

    To investigate temporal patterns, pollution concentrations and the health effects of air pollutants in Beijing we carried out time-series analyses on daily concentrations of ambient air pollutants and daily numbers of outpatient visits for otolaryngology over 2 years (2011-2012) to identify possible health effects of air pollutants. The results showed that PM10 was the major air pollutant in Beijing and that air quality was slightly better in 2012 than in 2011. Seasonal differences were apparent for SO2 and NO2. Both the background and urban areas of Beijing experienced particulate matter pollution in 2011. In addition to local air pollution, Beijing was also affected by pollutants transported from other regions, especially during heavy air pollution episodes. PM10, NO2, and SO2 concentrations showed positive associations with numbers of outpatient visits for otolaryngology during winter. NO2 and SO2 also had adverse ear, nose, and throat health effects outside of winter. The ear, nose, and throat health risks caused by air pollutants were higher during the winter than during the summer. NO2 had stronger influence on increased the likelihood of outpatient visits than SO2. The findings provide additional information about air quality and health effects of air pollution in Beijing.

  16. Survey on radioactive contamination in Beijing following the Japanese Fukushima nuclear accident.

    PubMed

    Lou, Yun; Wan, Ling; Ma, Yongzhong; Li, Huijuan; Meng, Qinghua; Kong, Yuxia; Zhu, Weijie; Wu, Dapeng; Cui, Limeng

    2013-09-01

    The radioactive contamination in Beijing caused by the Japanese Fukushima nuclear accident was monitored. In this research, samples of air, rainwater, surface water and vegetables in Beijing were collected and measured to estimate the radioactive contamination levels in Beijing. During the period from the 15th to the 41st day after the first emission of radioactive material (first emission) from the Japanese Fukushima nuclear power station (NPS) on 12 March 2011, obvious radioactive contamination was found in the Beijing air samples. The maximum concentration of I-131 was 5.89 mBq m(-3) in the air samples detected on the 22nd day after the first emission, and the maximum concentration of Cs-137 and Cs-134 was found on the 20th day after the first emission. Except for one sample of rainwater, no artificial radionuclides associated with Fukushima were found in surface water. The measurement results showed that there was no harm to the health of local Beijing residents.

  17. Findings of the fertility survey in Beijing municipality and other five provinces.

    PubMed

    1988-12-01

    The findings of the 2nd Chinese Fertility Survey, conducted in Beijing Municipality and the provinces of Liaoning, Shandong, Guangdong, Guizhou, and Gansu, indicate progress in the postponement of age at 1st marriage as well as increasing marital stability. The divorce rate ranged from 0.2-0.6% in the areas studied. Median age at 1st marriage is 3 years higher among women 25-29 years of age than among women 45-49 years of age. Among these younger women, median age at 1st marriage now stands at 23 years in Beijing Municipality and Liaoning, Shandong, and Guangdong Provinces and at 21-22 years in Guizhou and Gansu Provinces. The average. At present, the average number of children born is 1.63 in Beijing Municipality, 1.97 in Liaoning Province, 2.19 in Shandong, 2.67 in Guangdong, 2.79 in Gansu, and 3.47 in Guizhou Province. All the women surveyed were able to cite 4-7 birth control methods and have themselves used 1-2 methods (a low of 1 method in Guizhou and Gansu Provinces to a high of 1.7 in Beijing). Overall, 70% of the women of childbearing age surveyed were using contraceptive method at present. The highest contraceptive prevalence rate (84%) exists in Beijing Municipality.

  18. Population Exposure to PM2.5 in the Urban Area of Beijing

    PubMed Central

    Zhang, An; Qi, Qingwen; Jiang, Lili; Zhou, Fang; Wang, Jinfeng

    2013-01-01

    The air quality in Beijing, especially its PM2.5 level, has become of increasing public concern because of its importance and sensitivity related to health risks. A set of monitored PM2.5 data from 31 stations, released for the first time by the Beijing Environmental Protection Bureau, covering 37 days during autumn 2012, was processed using spatial interpolation and overlay analysis. Following analyses of these data, a distribution map of cumulative exceedance days of PM2.5 and a temporal variation map of PM2.5 for Beijing have been drawn. Computational and analytical results show periodic and directional trends of PM2.5 spreading and congregating in space, which reveals the regulation of PM2.5 overexposure on a discontinuous medium-term scale. With regard to the cumulative effect of PM2.5 on the human body, the harm from lower intensity overexposure in the medium term, and higher overexposure in the short term, are both obvious. Therefore, data of population distribution were integrated into the aforementioned PM2.5 spatial spectrum map. A spatial statistical analysis revealed the patterns of PM2.5 gross exposure and exposure probability of residents in the Beijing urban area. The methods and conclusions of this research reveal relationships between long-term overexposure to PM2.5 and people living in high-exposure areas of Beijing, during the autumn of 2012. PMID:23658832

  19. [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

  20. [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.

  1. 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.

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

    PubMed

    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

  3. 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

  4. Characteristics of ozone vertical profile observed in the boundary layer around Beijing in autumn.

    PubMed

    Ma, Zhiqiang; Zhang, Xiaoling; Xu, Jing; Zhao, Xiujuan; Meng, Wei

    2011-01-01

    In the autumn of 2008, the vertical profiles of ozone and meteorological parameters in the low troposphere (0-1000 m) were observed at two sites around Beijing, specifically urban Nanjiao and rural Shangdianzi. At night and early morning, the lower troposphere divided into two stratified layers due to temperature inversion. Ozone in the lower layer showed a large gradient due to the titration of NO. Air flow from the southwest brought ozone-rich air to Beijing, and the ozone profiles were marked by a continuous increase in the residual layer at night. The accumulated ozone in the upper layer played an important role in the next day's surface peak ozone concentration, and caused a rapid increase in surface ozone in the morning. Wind direction shear and wind speed shear exhibited different influences on ozone profiles and resulted in different surface ozone concentrations in Beijing.

  5. [Landscape ecological security assessment of Beijing City based on RS and GIS].

    PubMed

    Song, Yu-qin; Cao, Ming-lan

    2010-11-01

    By using RS, GIS, and landscape ecology methods, and based on the landscape structure, function, vitality, ecological sensitivity, and landscape pressure, an evaluation index system of landscape ecological security was constructed to analyze the landscape ecological security level and its spatiotemporal distribution pattern in Beijing City in 1988-2004. During the study period, the ecological service value of Beijing City was on a relatively high level, while the landscape vigor index and landscape pressure were on a relatively low level. The stability of landscape structure dropped, and the ecological sensitivity was also on a relatively low level. In 1998 and 2004, the landscape ecological security index of Beijing City was on a medium level, with the average value being 0.410 and 0.403, respectively, suggesting a slight deterioration in the landscape ecological security during the study period.

  6. 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.

  7. 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.

  8. 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.

  9. Mercury in urban soils with various types of land use in Beijing, China.

    PubMed

    Chen, Xi; Xia, Xinghui; Wu, Shan; Wang, Fan; Guo, Xuejun

    2010-01-01

    Mercury (Hg) concentration was investigated for 127 urban soil samples collected from business area (BA), classical garden (CG), culture and education area (CEA), public green space (PGS), residential area (RA) and roadside area (RSA) in Beijing. The median of Hg concentration in Beijing was 0.26 mg/kg. The value in CG was much higher than the other 5 types of land use, which was due to the historical use of Hg. More than 87% of the samples were not contaminated according to the guideline values of China, UK, Canada, and USEPA. Spatial distribution map revealed that Hg concentration showed a decreasing trend from the center to the suburb, it increased with the age of the urban area. Hg contamination in urban area of Beijing is marked by features of non-point sources associated with human activities, and it is most likely to be the common characteristics of Hg contamination in cities.

  10. Evidence of widespread ozone-induced visible injury on plants in Beijing, China.

    PubMed

    Feng, Zhaozhong; Sun, Jingsong; Wan, Wuxing; Hu, Enzhu; Calatayud, Vicent

    2014-10-01

    Despite the high ozone levels measured in China, and in Beijing in particular, reports of ozone-induced visible injury in vegetation are very scarce. Visible injury was investigated on July and August 2013 in the main parks, forest and agricultural areas of Beijing. Ozone injury was widespread in the area, being observed in 28 different species. Symptoms were more frequent in rural areas and mountains from northern Beijing, downwind from the city, and less frequent in city gardens. Among crops, injury to different types of beans (genera Phaseolus, Canavalia and Vigna) was common, and it was also observed in watermelon, grape vine, and in gourds. Native species such as ailanthus, several pines and ash species were also symptomatic. The black locust, the rose of Sharon and the Japanese morning glory were among the injured ornamental plants. Target species for broader bio-monitoring surveys in temperate China have been identified.

  11. Spatio-temporal variations of black carbon concentrations in the Megacity Beijing.

    PubMed

    Schleicher, Nina; Norra, Stefan; Fricker, Mathieu; Kaminski, Uwe; Chen, Yizhen; Chai, Fahe; Wang, Shulan; Yu, Yang; Cen, Kuang

    2013-11-01

    The spatial and temporal distribution and the flux of black carbon (BC) concentration in Beijing were continuously investigated over a two-year period at five sites to highlight the relative influence of contributing sources. The results demonstrate firstly that there is significant spatio-temporal variability of BC in Beijing. Highest concentrations occurred during winter primarily due to stagnant meteorological conditions, and seasonal BC sources, such as coal combustion for heating purposes. Biomass burning was identified as a minor seasonal source during the summer months. BC also varied spatially with higher concentrations in the SE of Beijing and lower concentrations in the NW, due to the differing emission intensity of various local BC sources such as traffic and industry. Frequently, overnight BC concentrations were higher due to specific meteorological conditions, such as the lower urban mixing layer height and various anthropogenic activities, such as exclusive night-time heavy duty vehicle traffic in the inner-city.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. [Source apportionment of aerosol lead in Beijing using absolute principal component analysis].

    PubMed

    Li, Yu-wu; Liu, Xian-de; Li, Bing; Yang, Hong-xia; Dong, Shu-ping; Zhang, Ting; Guo, Jing

    2008-12-01

    From 18 September 2005 to 13 September 2006 in Beijing, 166 TSP samples were collected at three sites in southern suburb, downtown and northern suburb, respectively. Lead and other 28 elements were determined for those samples by ICP-AES and ICP-MS methods. The lead average concentration of one year in southern suburb, downtown and northern suburb was 179, 142 and 102 ng x m(-3), respectively. Source identification and apportionment were carried out using absolute principal component analysis (APCA) method. Five groups of sources were recognized. The sources are nonferrous metallurgy (55.6%), coal combustion (16.9%), construction dust (11.8%) and soil dust (10.2%), respectively. Major sources of aerosol lead in Beijing were from nonferrous metallurgy industry. Lead associated with coal combustion and other sources were evenly distributed over three sites. However, industrial leadwas apparently at different levels at three sites, higher in southern suburb and lower in northern suburb. The lead concentration originated from nonferrous metallurgy at three sites from southern suburb, downtown to northern suburb was 113, 77.0 and 44.2 ng x m(-3), respectively, implying that the major sources for industrial lead were from the south to the Beijing. There is considerable space for reduction of aerosol lead concentration in Beijing. The main object for lead pollution discharge reduction and environmental management measures should aim at nonferrous metallurgy, especially for the field of lead metallurgy located at the south area to the Beijing. The calculation result based on the same chemical analysis data also shows that major source for TSP in Beijing is of soil dust and construction dust, accounting for 72.3%. The other sources such as coal combustion and nonferrous metallurgy account for 13.4% and 9.5%, respectively.

  17. The chemistry of precipitation and its relation to aerosol in Beijing

    NASA Astrophysics Data System (ADS)

    Tang, Aohan; Zhuang, Guoshun; Wang, Ying; Yuan, Hui; Sun, Yele

    Fifty-three rain events throughout the entire year of 2003 were collected in Beijing and the concentration of 15 major ions with the pH of the rainwater were analyzed. The close correlations of the acidity in rainwater with the concentrations of aerosol and gases in the air were observed and elaborated. The scavenging of the pollutants from the air directly affects the pH and composition of the rainwater. The major ions in rainwater in Beijing were SO 42-, NO 3-, Cl -, NH 4+, Ca 2+, Mg 2+, K +, and F -. The alkaline cations, NH 4+ and Ca 2+, acted as acid neutralizers and buffered the acidity of rain. The temporal variation of those major pollution ions in rainwater was similar to that of the air pollution. The concentrations of SO 42-, NO 3-, and NH 4+ have increased for the last two decades and likely indicated that the air pollution has become more and more serious in Beijing since the 1980s. The ratio of the concentration of SO 42- to NO 3- observed in 2003 was much lower than that in 1981, indicating that the air pollution resulting from the traffic emission, NO x, has been more significant. A remarkably positive correlation between pH and Ca 2+ concentration illustrates that Ca 2+ generally from mineral aerosols plays an important role in buffering rainwater acidity in Beijing and in northern China at all times. The concentrations of SO 42- and NO 3-, the predominant acid anions in rain, was much higher in Beijing than other cities, suggesting that the anthropogenic air pollution in Beijing has been a much more serious problem than other places.

  18. 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

  19. Establishment of Beijing underground pipeline information system based on ArcSDE

    NASA Astrophysics Data System (ADS)

    Yang, Bogang; Tao, Yingchun; Sui, Jianbo; Zhang, Feizhou

    2007-06-01

    Using GIS, network and database technologies, Beijing underground pipeline information system is established. After detailed analysis of the actuality and specialty of the present underground pipeline database managed by Beijing Institute of Surveying and Mapping (BISM), the paper systematically presents the studying purpose, meanings and primary contents. According to the study of pipeline data features, a spatio-temporal pipeline database classified by pipeline types is built. Based on the database, the urban underground pipeline information system is designed and developed by BISM, which unifies data from planning department and other departments, realizing modernized managements of underground pipeline data input, management, analysis and output.

  20. 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

  1. [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

  2. Aerosol Absorption Near Beijing During EAST-AIRE

    NASA Astrophysics Data System (ADS)

    Yang, M.; Howell, S.; Huebert, B.; Zhuang, J.

    2006-12-01

    To understand the aerosol absorption that had been observed offshore during ACE-Asia, we took a suite of instruments (including a 7 wavelength aethalometer) to a site 70 km ESE of Beijing in March of 2005 to measure the wavelength dependence of aerosol absorption as a part of the EAST-AIRE program. Confidence in filter methods suffers a bit because several corrections are required to estimate ambient absorption from particles on a filter: there is enhancement by multiple scatter from the filter's matrix, shadowing by thick cakes of collected particles, and scattering by co-collected aerosols, to name a few. We encountered mild dust, heavy pollution, relatively clean air, coal-burning chimney plumes, industrial plumes, and biomass burning, often at separate times. The absorption Angstrom exponent was always greater than 1, averaging 1.5: in the UV and violet there is an enhanced absorption over what one would expect of black carbon. If we assume that BC is responsible for all the absorption at 950 nm and that it has an Angstrom coefficient of 1.0 (yielding a specific absorbance of about 9 m2g-1 at 550 nm), the remaining absorption Angstrom exponent in the visible averaged 3.2. However, the 370-950 nm absorption spectrum of the remainder looked very much like the clay and hematite absorption spectra published by Sokolik and Toon, including a striking UV absorption and a characteristic dip around 660 nm (e.g., not a power law shape). This is not surprising, since clay is both a frequent component of dust and is used as a binder in the charcoal briquettes that are widely used in China for heating and cooking. We found single-scatter albedos virtually always less than 0.9, averaging 0.82. In the presence of dust, the SSA increased toward the IR. We also find that the clay spectrum explains virtually all the non-BC absorption, so there must not be much brown carbon present. Our confidence in these on-filter absorption measurements is increased by the fact that we

  3. A genome-wide analysis of multidrug-resistant and extensively drug-resistant strains of Mycobacterium tuberculosis Beijing genotype.

    PubMed

    Wu, Wei; Zheng, Huajun; Zhang, Lu; Wen, Zilu; Zhang, Shulin; Pei, Hao; Yu, Guohua; Zhu, Yongqiang; Cui, Zhenling; Hu, Zhongyi; Wang, Honghai; Li, Yao

    2013-09-01

    The Beijing genotype of Mycobacterium tuberculosis (MTB) is one of the most successful MTB lineages that has disseminated in the world. In China, the rate of multidrug-resistant (MDR) tuberculosis is significantly higher than the global average rate, and the Beijing genotype strains take the largest share of MDR strains. To study the genetic basis of the epidemiological findings that Beijing genotype has often been associated with tuberculosis outbreaks and drug resistance, we determined the genome sequences of four clinical isolates: two extensively drug resistant (XDR1219, XDR1221) and two multidrug resistant (WX1, WX3), using whole-genome sequencing. A large number of individual and shared SNPs of the four Beijing strains were identified. Our isolates harbored almost all classic drug resistance-associated mutations. The mutations responsible for drug resistance in the two XDR strains were consistent with the clinical quantitative drug resistance levels. COG analysis revealed that Beijing strains have significantly higher abundances of the mutations responsible for cell wall/membrane/envelope biogenesis (COG M), secondary metabolites biosynthesis, transport and catabolism (COG Q), lipid transport and metabolism (COG I) and defense mechanisms (COG V). The shared mutated genes of the four studied Beijing strains were significantly overrepresented in three DNA repair pathways. Our analyses promote the understanding of the genome polymorphism of the Beijing family strains and provide the molecular genetic basis for their wide dissemination capacity and drug resistance.

  4. Etude de la Production de Paires de Leptons dans les Interactions Proton-Beryllium a 450 GEV

    NASA Astrophysics Data System (ADS)

    Aubry, Pierre Rene Roger

    L'experience HELIOS a fait une etude precise de la production des paires e^+e^-, mu^+mu^-, mu ^+mu^-+nu, et mu^+/- e^+/- dans les interactions p-Be a 450 GeV. Le detecteur comporte un spectrometre a electrons, un spectrometre a muons, et un ensemble de calorimetres qui peuvent mesurer les photons et l'energie manquante emportee par les neutrinos. Les paires de leptons sont observees dans la region cinematique ^1: eqalign {2/m_mu 6 GeV cr E_{e}&>2.8 GeV cr.25&etude de la distribution en energie manquante des dimuons de masse intermediaire (1.2 GeV

  5. 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)".

  6. 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…

  7. 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

  8. 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

  9. 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

  10. 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…

  11. Ground-high altitude joint detection of ozone and nitrogen oxides in urban areas of Beijing.

    PubMed

    Chen, Pengfei; Zhang, Qiang; Quan, Jiannong; Gao, Yang; Zhao, Delong; Meng, Junwang

    2013-04-01

    Based on observational data of ozone (O3) and nitrogen oxide (NO(x)) mixing ratios on the ground and at high altitude in urban areas of Beijing during a period of six days in November 2011, the temporal and spatial characteristics of mixing ratios were analyzed. The major findings include: urban O3 mixing ratios are low and NO(x) mixing ratios are always high near the road in November. Vertical variations of the gases are significantly different in and above the planetary boundary layer. The mixing ratio of O3 is negatively correlated with that of NO(x) and they are positively correlated with air temperature, which is the main factor directly causing vertical variation of O3 and NO(x) mixing ratios at 600-2100 m altitude. The NO(x) mixing ratios elevated during the heating period, while the O3 mixing ratios decreased: these phenomena are more significant at high altitudes compared to lower altitudes. During November, air masses in the urban areas of Beijing are brought by northwesterly winds, which transport O3 and NO(x) at low mixing ratios. Due to Beijing's natural geographical location, northwest air currents are beneficial to the dilution and dispersion of pollutants, which can result in lower O3 and NO(x) background values in the Beijing urban area.

  12. Vocational Education and Productivity: A Case Study of the Beijing General Auto Industry Company.

    ERIC Educational Resources Information Center

    Min, Wei-Fang; Tsang, Mun Chiu

    1990-01-01

    Examines the economic rationale for vocationalizing secondary education in China by comparing vocational education graduates' and general education graduates' performance in the workplace. Using Beijing Auto Industry Company data, the study found that vocational-technical education graduates engaged in factory work relevant to their previous…

  13. 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…

  14. [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

  15. [Correlation between acidic materials and acid deposition in Beijing during 1997-2011].

    PubMed

    Chen, Yuan-yuan; Tian, He-zhong; Yang, Dong-yan; Zou, Ben-dong; Lu, Hai-feng; Lin, An-guo

    2013-05-01

    Based on the environment monitoring data and the ambient air quality data during the period of 1997-2011 from Beijing municipal environmental monitoring center, the correlations between primary pre-cursors of acid deposition, acidic materials and precipitation in Beijing area were analyzed in detail by taking economic development and energy mix into account. These results will be helpful for assessing the performance of environment quality improvement, as well as supplying scientific supporting information to make policies for national and local environment protection authorities. The main findings included as follows: there are significant correlations between the concentrations of NO2, NOx, and SO2 in the atmosphere, which indicated that both N and S in ambient air of Beijing came from fossil fuels combustion; acidic pollutants in the air are mainly discharged from local emission sources in Beijing, while there is no obvious correlation between S and N in wet deposition and concentrations of SO2, NO2 and NOx in the atmosphere, which demonstrated that concentrations of different ions in the acid deposition were influenced by both local sources as well as the inputs from other surrounding districts. Besides, the concentration of NO3- appeared to be correlative with the amount of motor vehicles, implying that the NOx from motor vehicles have contributed the increase of NO3- concentration of substantially.

  16. Pre-multidrug-resistant Mycobacterium tuberculosis Beijing strain associated with disseminated tuberculosis in a pet dog.

    PubMed

    Botelho, Ana; Perdigão, João; Canto, Ana; Albuquerque, Teresa; Leal, Nuno; Macedo, Rita; Portugal, Isabel; Cunha, Mónica V

    2014-01-01

    Resistance to isoniazid, ethambutol, and streptomycin was detected in a Mycobacterium tuberculosis strain, belonging to the Beijing family lineage, isolated from two nodule exudates of a Yorkshire terrier with generalized tuberculosis. This report alerts medical practitioners to the risk of dissemination of pre-multidrug-resistant tuberculosis (preMDR-TB) through exposure to M. tuberculosis-shedding pets.

  17. 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.

  18. 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.

  19. Laboratory Diagnosis and Genotype Identification of Scrub Typhus from Pinggu District, Beijing, 2008 and 2010

    PubMed Central

    Li, Weihong; Dou, Xiangfeng; Zhang, Liqin; Lyu, Yanning; Du, Zhizhong; Tian, Lili; Zhang, Xiuchun; Sun, Yulan; Guan, Zengzhi; Chen, Lijuan; Li, Xinyu; Wang, Quanyi

    2013-01-01

    This study was conducted to determine the diagnosis and genotype of Orientia tsutsugamushi in Pinggu district, Beijing. Indirect immunofluorescence assay (IFA) was performed to detect O. tsutsugamushi-specific immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies. Nested polymerase chain reaction (PCR) and DNA sequencing analysis targeting the O. tsutsugamushi-specific groEL gene and 56 kDa protein gene were performed on whole-blood samples from scrub typhus patients. We confirmed that 47 patients were infected with scrub typhus in Pinggu district, Beijing. Representative sequences amplified by primers according to the groEL gene (BJ-PG-2008; GenBank accession No. JQ894502) and the 56 kDa protein gene (PG-56kDa; GenBank accession No. JX843795) both clustered with Kawasaki. PG-56kDa had sequence homology of 100% with TADY12-0308, shandong-XDM2, Neimeng-90, and sdu-1 and sequence homology of 96% with Kawasaki, Taguchi, Oishi, and Kanda. We confirmed the genotype of O. tsutsugamushi in Pinggu district, Beijing, as Kawasaki, and the patient in 2008 confirmed in this study was the first patient with confirmed scrub typhus in Beijing. PMID:23716411

  20. Inversion of source parameters for moderate and small earthquakes in Beijing region

    NASA Astrophysics Data System (ADS)

    Lan, Cong-Xin; Liu, Jie; Zheng, Si-Hua; Ma, Shi-Zhen; Li, Ju-Zhen

    2005-09-01

    According to the geological structural features, Beijing and the adjacent areas can be divided into two regions of plain in the east and mountain in the west. Among the stations covered by the telemetered digital seismic station network of Earthquake Administration of Beijing Municipality, the stations in the plain area are all borehole ones and the stations in the western mountainous region are all located on the surface bedrock. In the paper, 511 waveform data recorded by the network from Oct. 2001 to Oct. 2004 are used in the researches for the entire Beijing region, the western mountainous region and the eastern plain area, respectively. The Q values are calculated for each area by Atkinson’s method and compared with the existed data. The reliability of the Q values and the reasons for the difference in the Q values are also discussed. Then, the source parameters and site response are inverted by the Moya’s method, in which two models are used. The first model uses the Q values, earthquakes and stations in the sub-areas and the second model uses the Q values, earthquakes and stations in the entire Beijing region. The results indicate that the source parameters and site responses obtained by two models are basically consistent with each other. It also indicates that the source parameters obtained by these methods are not affected by the size of station network.

  1. 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.

  2. Increased Foxp3 expression in guinea pigs infected with W-Beijing strains of M. tuberculosis

    PubMed Central

    Shang, Shaobin; Harton, Marisa; Tamayo, Marcela Henao; Shanley, Crystal; Palanisamy, Gopinath S.; Caraway, Megan; Chan, Edward D.; Basaraba, Randall J.; Orme, Ian M.; Ordway, Diane J.

    2011-01-01

    SUMMARY There is increasing evidence that clinical isolates of Mycobacterium tuberculosis that belong to the W-Beijing genotype of newly emerging strains are often of very high virulence when tested in small animal models, including the mouse and guinea pig. In this report we provide further evidence to support this contention, and show that two W-Beijing strains are of very high virulence when introduced by low dose aerosol into out-bred guinea pigs. In addition to severe lung pathology, each of these infections was associated with large influxes of activated CD4 and CD8 T cells into the lungs. Large influxes of macrophages were also observed, but the fraction of these showing evidence of activation by Class-II expression was relatively low. A progressive increase in neutrophils was also seen, with highest levels accumulating in the lungs of the W-Beijing infected animals. In the case of these two infections mRNA levels for TH1 cytokines was elevated early, but these then declined, and were replaced by increasing levels of message encoding for Foxp3, IL-10, and TGFβ. These observations support the hypothesis that W-Beijing strains are potent inducers of regulatory T cells, and that this event may enhance survival and transmission of these bacilli. PMID:21737349

  3. 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…

  4. Beijing In-Service Teachers' Self-Efficacy and Attitudes towards Inclusive Education

    ERIC Educational Resources Information Center

    Malinen, Olli-Pekka; Savolainen, Hannu; Xu, Jiacheng

    2012-01-01

    Four-hundred-and-fifty-one in-service teachers from the Beijing municipality filled in a questionnaire containing a Teacher Efficacy for Inclusive Practices (TEIP) scale. The aim was to examine the factor structure of the TEIP scale among mainland Chinese in-service teachers, and to investigate the relationship between self-efficacy for inclusive…

  5. Epidemiological study: Correlation between diet habits and constipation among elderly in Beijing region

    PubMed Central

    Yang, Xiao-Jiao; Zhang, Mei; Zhu, Hong-Ming; Tang, Zhe; Zhao, Dan-Dan; Li, Bang-Yi; Gabriel, Amanda

    2016-01-01

    AIM To investigate correlations between diet and prevalence of constipation among elderly people in Beijing. METHODS A total of 2776 (≥ 60 years) were selected in Beijing region for investigation. Data regarding constipation and diet habits was collected via hierarchical status, segmentation and random cluster sampling. Investigation included constipation-related demographic indicators and diet habits. Door-to-door questionnaires and surveys included daily staple food intakes, frequency of fish, egg, fruits and vegetables consumption. Constipation was defined according to the China Chronic Constipation Diagnosis and Treatment Guideline (2013), with the following constipation judgment indicators: decreased defecation frequency, dry and hard stool, and difficulty in defecation. RESULTS The prevalence of constipation among elderly people in Beijing region was 13%. There was a positive correlation between prevalence of constipation and age, but negative correlations between prevalence of constipation and staple food, fish and dietary fibres (fruits and vegetables) intakes. These differences were all statistically significant. CONCLUSION The prevalence of elderly constipation in Beijing region is closely related to diet habits, and is significantly decreased by high staple foods intake, fish eating and high dietary fibres (fruits and vegetables) consumption.

  6. Composes inter-halogenes sous pression: etude des transformations structurales dans le monobromure d'iode sous forme dense

    NASA Astrophysics Data System (ADS)

    Bouchard, Alexandre

    La famille des composes halogenes et inter-halogenes representent des solides moleculaires adoptant des phases denses communes avec des solides moleculaires diatomiques comme l'azote et l'hydrogene. Parmi les transformations structurales et electroniques induites sous haute pression et observees dans ces solides, on note, entre autres, la dissociation moleculaire et la metallisation. De plus, l'etude des phases denses de l'iode a permis recemment l'observation d'une structure cristalline possedant une modulation dite incommensurable, c'est-a-dire une modulation possedant une periodicite differente de celle de la structure cristalline, jetant ainsi une lumiere nouvelle sur le processus de dissociation moleculaire dans les solides halogenes. Dans ce memoire, on propose d'etudier les changements structuraux dans monobromure d'iode (IBr), un compose inter-halogene possedant des proprietes structurales semblables a celles de deux composes halogenes, soit l'iode (I 2) et le brome (Br2) sous leur forme solide. Des experiences de diffraction des rayons X de poudres en utilisant un rayonnement synchrotron ont ete realisees a temperature ambiante sur l'IBr en variant la pression jusqu'aux environs de 60 GPa. La nature chimique particuliere du compose IBr a necessite la mise au point de techniques de chargement d'echantillon destinees a preserver l'integrite chimique de la substance utilisee. On rapporte egalement l'observation d'une phase de l'IBr presentant une modulation incommensurable. Les phases observees dans l'IBr permettent d'etablir des paralleles avec les phases denses rapportees dans I2 et Br2 par le biais d'un modele phenomenologique decrivant la sequence structurale des solides halogenes sous forme condensee.

  7. 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

  8. 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.

  9. 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

  10. 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

  11. Satellite Air Quality Monitoring Before, During and After the Beijing 2008 Olympics and Paralympics

    NASA Astrophysics Data System (ADS)

    Witte, J. C.; Schoeberl, M. R.; Krotkov, N. A.; Pickering, K. E.; Streets, D. G.; Gleason, J. F.; Gille, J. C.

    2009-12-01

    In 2001, Beijing, China was awarded the hosting rights to the 2008 Olympic and Paralympic Games. Since then, the government has gradually implemented pollution emission control strategies to improve Beijing's air quality in preparation for both games. Long-term industrial and short-term vehicle emission controls have also been enforced upwind of Beijing's neighboring provinces to the south and west. This region is characterized by numerous heavy-polluting industries whose emissions are typically transported towards Beijing, significantly impacting the city's air quality. We examine the efficacy of these emission control measures on tropospheric NO2, SO2, and CO pollution using satellite data from Aura's Ozone Monitoring Instrument (OMI) and Terra's Measurements Of Pollution In The Troposphere (MOPITT) from 2004 to the present. During both games, held in August and September 2008, OMI and MOPITT measured significant decreases in all three tracer gases compared to the past three years: NO2 (-43%), SO2 (-13%), and CO (-12%). This decrease in CO and SO2 over northeastern China continues through 2009, reflecting the longer-term nature of emission controls on heavily polluting industries. The global recession is also a likely contributor, as factories have shut down or slowed production due to the decrease in demand for manufactured goods. The tropospheric NO2 column over Beijing returned to typical monthly mean values when controls on vehicle emissions were lifted by the end of September 2008. However, we observe a slight NO2 decrease at the beginning of 2009 relative to 2008 suggesting a decrease in the contribution of industrial emissions of NOx to the overall NO2 column.

  12. Current Status of Diagnosis And Treatment of Primary Breast Cancer in Beijing, 2008

    PubMed Central

    Yuan, Xiao-mei; Wang, Ning; Ouyang, Tao; Yang, Lei; Song, Ming-yang; Lin, Ben-yao; Xie, Yun-tao; Li, Jin-feng; Pan, Kai-feng; You, Wei-cheng; Zhang, Lian

    2011-01-01

    Objective To investigate the status of diagnosis and treatment of primary breast cancer in Beijing, 2008. Methods All the patients who were diagnosed as primary breast cancer in Beijing in 2008 were enrolled in this study. Information of these patients, including the features of tumors, clinical diagnosis and treatment was collected, and filled in the well-designed questionnaire forms by trained surveyors. The missing data was partly complemented through telephone interviews. Results A total of 3473 Beijing citizens were diagnosed as primary breast cancer (25 patients with synchronal bilateral breast cancer) in Beijing, 2008. Of them 82.09% were symptomatic. 19.02% and 34.11% were diagnosed using fine needle aspiration biopsy (FNAB) and core needle biopsy (CNB), respectively. 15.92% received sentinel lymph node biopsy (SLNB) and 24.27% received breast conserving surgery (BCS). Among 476 cases with Her-2 positive, only 96 received anti-Her-2 therapy. We found that the standardization level varied in hospitals of different grades, with higher level in Grade-III hospitals. Of note, some breast cancer patients received non-standard primary tumor therapy: 65.63% of the patients with ductal carcinoma in situ (DCIS) received axillary lymph node dissection and 36.88% received chemotherapy; 25.89% of the patients underwent breast conserving surgery without margin status; 12.10% of the patients received chemotherapy less than 4 cycles. Conclusion Although most breast cancer patients received basic medical care, the mode of diagnosis and treatment should be improved and should be standardized in the future in Beijing. PMID:23467615

  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. 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

  15. 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

  16. Impacts of sewage irrigation on heavy metal distribution and contamination in Beijing, China.

    PubMed

    Liu, Wen-hua; Zhao, Jing-zhu; Ouyang, Zhi-yun; Söderlund, Leif; Liu, Guo-hua

    2005-08-01

    A potential hazard to Beijing was revealed due to the accumulation trend of heavy metals in agricultural soils with sewage irrigation, which results in metal contamination and human exposure risk. Samples including soils and plants were collected to assess the impacts of sewage irrigation on the irrigated farming area of Beijing. Concentrations of the five elements Cd, Cr, Cu, Zn, and Pb were determined in samples to calculate the accumulation factor and to establish a basis for environmental protection and the suitability of sewage irrigation for particular land use in the urban-rural interaction area of Beijing. Using reference values provided by the Beijing Background Research Cooperative Group in the 1970s, the pollution load index (PLI), enrichment factor (EF), and contamination factor (CF) of these metals were calculated. The pollution load indices (sewage irrigation land 3.49) of soils indicated that metal contamination occurred in these sites. The metal enrichment (EF of Cd 1.8, Cr 1.7, Cu 2.3, Zn 2.0, Pb 1.9) and the metal contamination (CF of Cd 2.6, Cr 1.5, Cu 2.0, Zn 1.7, Pb 1.6) showed that the accumulation trend of the five toxic metals increased during the sewage irrigation as compared with the lower reference values than other region in China and world average, and that pollution with Cd, Cu, Zn, and Pb was exacerbated in soils. The distributions of these metals were homogeneous in the irrigation area, but small-scale heterogeneous spatial distribution was observed. Irrigation sources were found to affect heavy metal distributions in soils. It was suggested that heavy metal transfer from soils to plants was a key pathway to human health exposure to metal contamination. However, with the expansion of urban areas in Beijing, soil inhalation and ingestion may become important pathways of human exposure to metal contamination.

  17. Oxidative potential and inflammatory impacts of source apportioned ambient air pollution in Beijing.

    PubMed

    Liu, Qingyang; Baumgartner, Jill; Zhang, Yuanxun; Liu, Yanju; Sun, Yongjun; Zhang, Meigen

    2014-11-01

    Air pollution exposure is associated with a range of adverse health impacts. Knowledge of the chemical components and sources of air pollution most responsible for these health effects could lead to an improved understanding of the mechanisms of such effects and more targeted risk reduction strategies. We measured daily ambient fine particulate matter (<2.5 μm in aerodynamic diameter; PM2.5) for 2 months in peri-urban and central Beijing, and assessed the contribution of its chemical components to the oxidative potential of ambient air pollution using the dithiothreitol (DTT) assay. The composition data were applied to a multivariate source apportionment model to determine the PM contributions of six sources or factors: a zinc factor, an aluminum factor, a lead point factor, a secondary source (e.g., SO4(2-), NO3(2-)), an iron source, and a soil dust source. Finally, we assessed the relationship between reactive oxygen species (ROS) activity-related PM sources and inflammatory responses in human bronchial epithelial cells. In peri-urban Beijing, the soil dust source accounted for the largest fraction (47%) of measured ROS variability. In central Beijing, a secondary source explained the greatest fraction (29%) of measured ROS variability. The ROS activities of PM collected in central Beijing were exponentially associated with in vivo inflammatory responses in epithelial cells (R2=0.65-0.89). We also observed a high correlation between three ROS-related PM sources (a lead point factor, a zinc factor, and a secondary source) and expression of an inflammatory marker (r=0.45-0.80). Our results suggest large differences in the contribution of different PM sources to ROS variability at the central versus peri-urban study sites in Beijing and that secondary sources may play an important role in PM2.5-related oxidative potential and inflammatory health impacts.

  18. [Spatial changes and sources of nitrate in Beijing urban ecosystem surface water].

    PubMed

    Xu, Zhi-wei; Zhang, Xin-yu; Ren, Yu-fen; Sun, Xiao-min; Wang, Xiao-ke; Wang, Sheng-zhong

    2012-08-01

    The spatial variation in nitrate-nitrogen (NO3- -N) concentrations in surface water of ten sampling sites in the Beijing urban ecosystem from Kunminghu Lake to Tonghui River were assessed using monitoring data from 2009 to 2010. Nitrogen sources were examined using a hydro-chemical method. The results showed that the average nitrate-N concentrations of surface water in the Beijing urban ecosystem ranged from 0.7-7.6 mg x L(-1), with concentrations at all sites affected by human activities to a varying degree. The nitrate-N concentrations in the Dongbianmen and Tonghui River located in the southeastern of Beijing ranged from 7.0-7.6 mg x L(-1) and were significantly higher than those in the upper reaches (P < 0.01). For all sampling sites, the chloride concentrations fell between 14.8-86.0 mg x L(-1). The chloride concentrations at the furthest downstream sites, in the Dongbianmen and Tonghui River, ranged from 81.5-85.0 mg x L(-1) and were 2.3-5.8 times higher than those in the upper reaches. This indicates that the surface water in Dongbianmen and Tonghui River is clearly affected by human activities and that there are outfalls or pollutant sources near these two sampling sites. Further, the Cl-/Na+, SO4(2-)/Ca2+ ratios showed that the majority of nitrate-N came from a single source. The information given by the nitrate-N concentrations combined with the NO3- -N/Cl- ratio implied that sewage effluent, including industrial waste water, leakage from solid waste disposal and domestic wastewater mainly controlled nitrate distribution in the Beijing urban surface water. The results from this study suggest that surface water management should focus on downstream sites located in the southeastern region of Beijing such as the Dongbianmen and Tonghui River in the future.

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. 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

  4. 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

  5. Modeling analysis of the seasonal characteristics of haze formation in Beijing

    NASA Astrophysics Data System (ADS)

    Han, X.; Zhang, M.; Gao, J.; Wang, S.; Chai, F.

    2013-11-01

    The air quality modeling system RAMS-CMAQ coupled with an aerosol optical property scheme was applied to simulate the meteorological field, major aerosol components (sulfate, nitrate, ammonium, black carbon, organic carbon, dust, and sea salt), and surface visibility over the North China Plain (NCP) in 2011. The modeled results in February and July 2011 were selected and analyzed to obtain an in-depth understanding of the haze formation mechanism in Beijing in different seasons. The evaluations suggested that the modeling system provided reliable simulation results of meteorological factors (temperature, relative humidity, and wind field), visibility, mass concentrations of gaseous pollutants (NO2 and O3), and major aerosol components in PM2.5 by compared with various observation data at several measurement stations over NCP. The simulation results showed that the visibility below 10 km covered most regions of NCP and dropped below 5 km over the urban areas of Beijing, Tianjin, and Shijiazhuang during the pollution episodes in February and July. The heavy particulate pollutants were concentrated in the same areas as well. The heavy loading of PM2.5 which could reach 300 μg m-3 in Beijing should be the main reason of haze occurrence in February, and the visibility generally decreased to 3-5 km when the mass concentration of PM2.5 exceeded 200 μg m-3. However, similar values of visibility also appeared in July when the mass concentration of PM2.5 was merely in the range of 120 μg m-3 to 200 μg m-3. Analysis presented that nitrate, sulfate, and ammonium were the three major aerosol components in Beijing and their total mass burden was even higher in July than that in February. Thus, the significantly higher relative humidity and larger mass proportion of soluble aerosol components resulted in more haze days in July. Sensitivity test shows that the mass concentration threshold of PM2.5 to cause haze occurrence was about 80 μg m-3 when the relative humidity was 70

  6. [Observation on atmospheric pollution in Xianghe during Beijing 2008 Olympic Games].

    PubMed

    Pan, Yue-Peng; Wang, Yue-Si; Hu, Bo; Liu, Quan; Wang, Ying-Hong; Nan, Wei-Dong

    2010-01-01

    There is a concern that much of the atmospheric pollution experienced in Beijing is regional in nature and not attributable to local sources. The objective of this study is to examine the contribution of sources outside Beijing to atmospheric pollution levels during Beijing 2008 Olympic Games. The observations of SO2, NO(x), O3, PM2.5 and PM10 were conducted from June 1 to September 30, 2008 in Xianghe, a rural site about 70 km southeast of Beijing. Sources and transportation of atmospheric pollution during the experiment were discussed with surface meteorology data and backward trajectories calculated using HYSPLIT model. The results showed that the daily average maximum (mean +/- standard deviation) concentrations of SO2, NO(x), O3, PM2.5, and PM10 during observation reached 84.4(13.4 +/- 15.2), 43.3 (15.9 +/- 9.1), 230 (82 +/- 38), 184 (76 +/- 42) and 248 (113 +/- 52) microg x m(-3), respectively. In particular, during the pollution episodes from July 20 to August 12, the hourly average concentration of O3 exceeded the National Ambient Air Quality Standard II for 46 h (9%), and the daily average concentration of PM10 exceeded the Standard for 11 d (46%); PM2.5 exceeded the US EPA Standard for 18 d (75%). The daily average concentrations of SO2, NO(x), O3, PM2.5 and PM10 decreased from 27.7, 18.6, 96, 90, 127 microg x m(-3) in June-July to 5.8, 13.2, 80, 60, 106 microg x m(-3) during Olympic Games (August-September), respectively. The typical diurnal variations of NO(x), PM2.5 and PM10 were similar, peaking at 07:00 and 20:00, while the maximum of O3 occurred between 14:00 to 16:00 local time. The findings also suggested that the atmospheric pollution in Xianghe is related to local emission, regional transport as well as the meteorological conditions. Northerly wind and precipitation are favorable for diffusion and wet deposition of pollutants, while sustained south flows make the atmospheric pollution more serious. The lead-lag correlation analysis during the

  7. 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

  8. Tuberculous spondylitis in Russia and prominent role of multidrug-resistant clone Mycobacterium tuberculosis Beijing B0/W148.

    PubMed

    Vyazovaya, Anna; Mokrousov, Igor; Solovieva, Natalia; Mushkin, Alexander; Manicheva, Olga; Vishnevsky, Boris; Zhuravlev, Viacheslav; Narvskaya, Olga

    2015-04-01

    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

  9. Mapping IS6110 in high-copy number Mycobacterium tuberculosis strains shows specific insertion points in the Beijing genotype

    PubMed Central

    2013-01-01

    Background Mycobacterium tuberculosis Beijing strains are characterized by a large number of IS6110 copies, suggesting the potential implication of this element in the virulence and capacity for rapid dissemination characteristic of this family. This work studies the insetion points of IS6110 in high-copy clinical isolates specifically focusing on the Beijing genotype. Results In the present work we mapped the insertion points of IS6110 in all the Beijing strains available in the literature and in the DNA sequence databases. We generated a representative primer collection of the IS6110 locations, which was used to analyse 61 high-copy clinical isolates. A total of 440 points of insertion were identified and analysis of their flanking regions determined the exact location, the direct repeats (DRs), the orientation and the distance to neighboring genes of each copy of IS6110. We identified specific points of insertion in Beijing strains that enabled us to obtain a dendrogram that groups the Beijing genotype. Conclusions This work presents a detailed analysis of locations of IS6110 in high-copy clinical isolates, showing points of insertion present with high frequency in the Beijing family and absent in other strains. PMID:23800083

  10. 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

  11. 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.

  12. Measurements and characteristics of nitrogen-containing compounds in atmospheric particulate matter in Beijing, China

    SciTech Connect

    Duan, F.K.; Liu, X.D.; He, K.B.; Dong, S.P.

    2009-03-15

    The total nitrogen (TN) and water-soluble nitrogenous ions were determined by using CHN Elemental Analyzer and ion chromatography method, respectively, from November 24, 1998 to February 12, 1999 in Beijing. The average concentrations of TN, NH{sub 4}{sup +} and NO{sub 3}{sup -} were 10.62 {mu} g N m{sup -3}, 6.67 {mu} g m{sup -3} and 10.01 {mu} g m{sup -3}, respectively. The total inorganic nitrogen (IN) calculated from NH{sub 4}{sup +} and NO{sub 3}{sup -} was 7.45 {mu} g N m{sup -3}, accounting for 70% of TN, i.e., 30% of TN existed as organic nitrogen form (ON). The correlation between ON and other pollution tracers showed that, coal combustion, biomass burning, soil humic matter and secondary formation were the important sources of ON in particulate matter in Beijing.

  13. 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.

  14. Serological survey of 2009 H1N1 influenza in residents of Beijing, China.

    PubMed

    Deng, Y; Pang, X H; Yang, P; Shi, W X; Tian, L L; Liu, B W; Li, S; Cui, S J; Li, Y; Lu, G L; Zhang, L; Zhang, X; Liu, B; Seale, H; Huang, F; Wang, Q Y

    2011-01-01

    In order to determine the prevalence of antibody against 2009 H1N1 influenza in Beijing, we conducted a serological survey in 710 subjects, 1 month after the epidemic peak. We found that 13·8% of our cohort was seropositive. Subjects aged ≥60 years recorded the lowest seroprevalence (4·5%). The age-weighted seroprevalence of 14·0% was far lower than the supposed infection rate at the epidemic peak, derived from the basic reproduction number for 2009 H1N1 virus. For subjects who had received the pandemic vaccine seroprevalence was 51·4%. In subjects aged ≥60 years the seasonal influenza vaccination was not significantly associated with being seropositive. Our study suggests that many factors, and not just the immunological level against 2009 H1N1 influenza in the community, affected the spread of the virus within the population of Beijing. PMID:20854713

  15. 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.

  16. 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.

  17. 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

  18. 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%.

  19. 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.

  20. 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.

  1. 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.

  2. Estimation of amphetamine and methamphetamine uses in Beijing through sewage-based analysis.

    PubMed

    Li, Jing; Hou, Linlin; Du, Peng; Yang, Jun; Li, Kaiyang; Xu, Zeqiong; Wang, Congcong; Zhang, Huafang; Li, Xiqing

    2014-08-15

    Sewage epidemiology has been proven as an effective approach to estimate the use of illicit drugs by a population. In this study, sewage analysis was applied to examine the patterns of amphetamine (AMP) and methamphetamine (METH) uses in the urban area of Beijing. Influent and effluent samples were collected from all the thirteen sewage treatment plants (STPs) in the urban area during two sampling campaigns. METH concentrations in influents were found to range from several tens to several hundred ng·L(-1), whereas AMP concentrations ranged from several to several tens ng·L(-1). The concentration ratios between AMP and METH in influents at most STPs were close to the rate of AMP excretion following METH ingestion, indicating that AMP in sewage in Beijing was predominately from the metabolism of METH. Much higher METH loads were observed in the center part of the urban area in Beijing, indicating a strong correlation between METH use and economic level and entertainment activities. Seasonal variation in METH loads was significant, with greater use in summer than in winter. Significant difference in METH loads between weekdays and weekend days were observed in winter but not in summer. No clear trend in diurnal variation of METH use was observed. Nearly complete removal of METH occurred at the STPS in Beijing. Apparent removal rates of AMP were lower than those of METH, likely due to degradation of METH into AMP during the wastewater treatment processes. In summary, this study represents the first application of sewage epidemiology to the entire urban population of a metropolitan in mainland China and provided an overview of METH and AMP uses in the city.

  3. [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).

  4. [Investigation of heavy metal and polycyclic aromatic hydrocarbons contamination in street dusts in urban Beijing].

    PubMed

    Xiang, Li; Li, Ying-Xia; Shi, Jiang-Hong; Liu, Jing-Ling

    2010-01-01

    This paper investigated the contamination levels of heavy metal and polycyclic aromatic hydrocarbons (PAHs) in street dusts in different functional areas in urban Beijing. Results show that the mean concentrations of Cd, Hg, Cr, Cu, Ni, Pb and Zn in street dusts in Beijing are 710 ng/g, 307 ng/g, 85.0 microg/g, 78.3 microg/g, 41.1 microg/g, 69.6 microg/g and 248.5 microg/g, respectively, which are significantly lower than those in most cities around the world and Shenyang, Shanghai in China. The mean concentration of Sigma 16PAHs in street dusts in Beijing is 0.398 microg/g, which is also lower than those of Handan, Tianjin and Shanghai. Non-parametric Friedman test demonstrates significant differences of heavy metal contents on street dusts from different functional zones. Street dusts in residential area and parks have lower heavy metal and PAHs concentrations than the street dusts from areas of high traffic density. The concentrations of heavy metals follow the order Zn > Cr > Cu > Pb > Ni > Cd > Hg, which is consistent with the situation in other cities around the world. The geoaccumulation index analysis shows that street dust in urban Beijing is moderately polluted by Cd, Zn and Cu, little polluted by Cr and Pb and practically unpolluted by Ni. The contamination levels of Sigma 16PAHs on street dusts vary greatly in different functional zones with parks little polluted, residential areas moderately to strongly polluted and traffic related areas strongly polluted to extremely polluted. Mass loading of heavy metals and PAHs is largely associated with street dusts of size range < 300 microm. Therefore, the urban sweeping vehicles should update the dust sweeping devices to remove not only the fine particle but also the coarser particles.

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. [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

  10. [Changing characteristics of the main air pollutants of the Dongling Mountain in Beijing].

    PubMed

    Yu, Yang-Chun; Hu, Bo; Wang, Yue-Si

    2013-07-01

    Concentrations of SO2, NO(x), O3 and PM2.5 were observed from August 2009 to June 2011 in Beijing forest ecology observation site which locates at the Dongling Mountain of Beijing. Monthly, seasonal variation and statistical diurnal variation characteristics of air pollutants were analyzed. Besides, the influence of transportation to air pollutants was also discussed combined with the back trajectories of air mass. The average concentrations of NO, NO2, NO(x), O3, SO2 and PM2.5 were (2.0 +/- 1.6), (13.2 +/- 7.2), (15.3 +/- 8.2), (61.0 +/- 19.6), (3.6 +/- 3.6) and (35.6 +/- 32.0) microg x m(-3), respectively. The concentration of pollutants in Beijing forest ecology observation site was lower than that in rural observation site in Beijing. The highest value of NO(x) appeared in autumn while the lowest appeared in summer, and concentrations of NO(x) in autumn and summer were (17.0 +/- 8.0) microg x m(-3) and (13.8 +/- 4.1) microg x m(-3), respectively. Concentrations of O3 in spring and summer were higher than those in autumn and winter. The highest concentration of O3 appeared in June. The concentration of SO2 in winter was the highest, and this concentration was 2.7 times to the lowest concentration in summer. The highest concentration of PM2.5 appeared in summer and was 56.4 microg x m(-3). There were obvious diurnal variation of NO(x), O3 and SO2. There are two peaks of NO(x) have been observed, however there are only one peak of O3 and SO2 has been observed. There was no obvious diurnal variation of PM2.5 to other pollutants.

  11. 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.

  12. 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 %.

  13. Wintertime peroxyacetyl nitrate (PAN) in the megacity Beijing: role of photochemical and meteorological processes.

    PubMed

    Zhang, Hualong; Xu, Xiaobin; Lin, Weili; Wang, Ying

    2014-01-01

    Previous measurements of peroxyacetyl nitrate (PAN) in Asian megacities were scarce and mainly conducted for relative short periods in summer. Here, we present and analyze the measurements of PAN, O3, NO(x), etc., made at an urban site (CMA) in Beijing from 25 January to 22 March 2010. The hourly concentration of PAN averaged 0.70 x 10(-9) mol/mol (0.23 x 10(-9) -3.51 x 10(-9) mol/mol) and was well correlated with that of NO2 but not O3, indicating that the variations of the winter concentrations of PAN and 03 in urban Beijing are decoupled with each other. Wind conditions and transport of air masses exert very significant impacts on O3, PAN, and other species. Air masses arriving at the site originated either from the boundary layer over the highly polluted N-S-W sector or from the free troposphere over the W-N sector. The descending free-tropospheric air was rich in O3, with an average PAN/O3 ratio smaller than 0.031, while the boundary layer air over the polluted sector contained higher levels of PAN and primary pollutants, with an average PAN/O3 ratio of 0.11. These facts related with transport conditions can well explain the observed PAN-O3 decoupling. Photochemical production is important to PAN in the winter over Beijing. The concentration of the peroxyacetyl (PA) radical was estimated to be in the range of 0.0014 x 10(-12) -0.0042 x 10(-12) mol/mol. The contributions of the formation reaction and thermal decomposition to PAN's variation were calculated and found to be significant even in the colder period in air over Beijing, with the production exceeding the decomposition. PMID:24649694

  14. 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

  15. 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.

  16. [Species composition and spatial structure of plants in urban parks of Beijing].

    PubMed

    Zhao, Juan-Juan; Ouyang, Zhi-Yun; Zheng, Hua; Xu, Wei-Hua; Wang, Xiao-Ke

    2009-02-01

    By the method of stratified random sampling, the species composition and spatial structure of the plants in 53 parks in Beijing urban area were investigated, aimed to provide basic information for the protection of plant diversity in the parks and the management of the parks. A total of 492 plant species belong to 96 families and 283 genera were recorded. Based on the data of 21 investigation items about the trees, shrubs, and grasses in the study area and related statistical analyses, the plant structural patterns commonly seen in the green space of the parks of Beijing urban area were introduced. Among the plants in the parks, native species occupied 53.86% of the total. The chorological composition of the genera embraced broad kinds of geographical elements in China, and the predominance of dominant plants was remarkable. In most green patches of the parks, herbaceous species were more abundant and had higher coverage, shrubs had relatively low coverage and were less beneath tree canopy, and trees and shrubs had lower species richness and density. The canopy breadth and the diameter of breast height of trees as well as the breadth of shrubs and the heights of trees and shrubs were basically at the second grade, but the canopy structure of the trees were better, with good conditions of sunlight and growth. The crown missing of the shrubs was relatively low. It was suggested from correlation analyses and document survey of Beijing parks construction history that park landscape design, alien species introduction; and cultivation management were the main factors affecting the species composition and spatial structure of the plants in Beijing urban parks. PMID:19459367

  17. Source contributions to ambient concentrations of CO and NOX in the urban area of Beijing.

    PubMed

    Hao, J; Wu, Y; Fu, L; He, D; He, K

    2001-01-01

    An emission inventory based on GIS technology was developed in this study, and used to estimate the spatial distribution of the stationary and mobile sources in the urban area of Beijing. The stationary sources were divided into various types of finer classes depending on different usage, stack height and emission factors. The mobile sources were treated as both line sources and area sources. It was shown that total anthropogenic CO and NOX emissions had reached 1.4 million and 233 thousand tons, respectively, and vehicle sources emissions of CO and NOX accounted for 76.8% and 40.2%, respectively, of the total emissions in 1995. ISCST3, a Gaussian dispersion air quality model, was modified at low wind speed condition, and then used to facilitate the study of source contributions to ambient concentrations of CO and NOX in Beijing. The simulation results showed that emissions from the vehicle sources had contributed 76.5% and 68.4% of the total CO and NOX concentrations in urban atmosphere of Beijing in 1995, and were even higher in the city core (86.3% of the CO and 72.0% of the NOX). Therefore, strategies for CO and NOX pollution control will of necessity need to focus on the vehicle sources. PMID:11382022

  18. 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

  19. 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.

  20. Sensitivity of ozone to precursor emissions in urban Beijing with a Monte Carlo scheme

    NASA Astrophysics Data System (ADS)

    Tang, Xiao; Wang, Zifa; Zhu, Jiang; Gbaguidi, Alex E.; Wu, Qizhong; Li, Jie; Zhu, Tong

    2010-10-01

    In order to understand the formation mechanisms of high surface ozone and identify the main contributor sources in Beijing, this study investigates the sensitivity of surface ozone to NO, NO 2 and nine types of NMVOC emissions during a photochemical smog episode. Monte Carlo sensitivity analysis scheme with fifty simulations is established based on the Nested Air Quality Prediction Model System (NAQPMS). At every simulation, each of the eleven precursor emissions is perturbed with a distinct set of perturbations. The sensitivities of ozone to emissions are identified by multiple linear regressions. The stability of sensitivity results is validated by two experiments with standard deviations of log-normal perturbations set as 30% and 50% respectively. The sensitivity results suggest that the current high surface ozone is strongly stimulated by NMVOC emissions. Among NMVOC emissions, formaldehyde, ethylene and olefins emissions present the greatest impacts on ozone. On the other hand, NOx emissions have a strong inhibitory effect on ozone formation, even after 50% NOx emission reduction. This indicates that the current ozone formation in Beijing is under NOx-saturated conditions. A transition of ozone formation is observed from NOx-saturated to NOx-limited sensitivity behavior with a 75% reduction of NOx emissions. This study gives the implication that abatement of the four NMVOC types mentioned above could be efficient on reducing the high levels of surface ozone in central urban Beijing, while inadequate abatement in NOx emissions probably induces reverse effects.

  1. 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.

  2. 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

  3. [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

  4. 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.

  5. 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.

  6. Aging Beijing: challenges and strategies of health care for the elderly.

    PubMed

    Chen, Zheng; Yu, Jia; Song, Yuetao; Chui, Dehua

    2010-11-01

    Following the global trend of population aging, China became an aging society at the end of the 20th century. The ever-growing medical demands of the elderly, the lag in medical insurance policy, and the late development of geriatric services make the present situation of public health in China worrying. To meet these challenges, the Beijing municipal government has actively adjusted its development strategies and has been building up a medical service and healthcare system suitable for the elderly. The core of the system is a three-level management of geriatric diseases: prevention and treatment for chronic diseases, functional rehabilitation, long-term care, and family attendance at rural and urban community health service centers (stations); post-acute rehabilitation, long-term care, and palliative treatment in the specialized geriatric hospitals of every district (county); and rescue and treatment for acute and serious geriatric diseases in the geriatric sections of all general hospitals and Beijing Geriatric Hospital. By raising awareness and gaining support from all of society, the implementation of this system will benefit millions of elderly people and promote the sustainable financial development and social harmony of Beijing. PMID:20667512

  7. [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.

  8. “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.

  9. 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.

  10. [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.

  11. Effects of land use intensity on the natural attenuation capacity of urban soils in Beijing, China.

    PubMed

    Wang, Meie; Faber, Jack H; Chen, Weiping; Li, Xiaoma; Markert, Bernd

    2015-07-01

    Urban soils are major sinks that provide the services of attenuating and detoxifying environmental pollutants. This significant ecosystem service of urban soil can be evaluated by the natural attenuation capacity (NAC). In this research, we develop a method to calculate the natural pollutant attenuation capacity of urban soils on the basis of 5 chemical and physical measurements. By selecting municipal parks soils for reference, we assessed the spatial and temporal changes of NAC in Beijing city soils under influences of rapid urbanization. Results indicated that NAC was increasingly impacted by land use in the order: parksBeijing built-up area resembled the age of urbanization. Regional hot spots of NAC corresponded to the land use distribution and the urbanization progress in Beijing city. The developed index can be used to assess the impacts of urbanization on soil ecosystem services of natural attenuation of contaminants.

  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. Mass Media and HIV/AIDS Prevention Among Female Sex Workers in Beijing, China.

    PubMed

    Xiao, Zhiwen; Li, Xiaoming; Lin, Danhua; Tam, Cheuk Chi

    2015-01-01

    The current study aimed to identify the sources of HIV prevention information for female sex workers in Beijing and assess the associations between levels of mass media exposure of HIV/AIDS prevention information and HIV/AIDS knowledge as well as condom use-related attitudes, beliefs, and behaviors. Cross-sectional data were collected from 359 female sex workers in Beijing, China. Chi-square tests and one-way ANOVA tests were employed. Female sex workers sampled in Beijing were more likely to obtain HIV/AIDS prevention information from television and street posters than radio and the Internet. However, a higher level of exposure to and a lasting impression on online information were significantly associated with a higher level of condom use self-efficacy and more consistent condom use among the participants. Exposure to HIV/AIDS prevention information delivered by radio, street posters, and the Internet was found to be associated with sexual communication about HIV or condom use with sexual partners. Overall, this study provides preliminary evidence of the utility of various mass media outlets in delivering HIV/AIDS prevention information among female sex workers in China. Future studies are needed to systematically examine the effectiveness of mass media-based prevention education on HIV/AIDS related attitudes and behaviors among female sex workers and other populations in China.

  14. "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.

  15. 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

  16. 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

  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. 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.

  19. Source apportionment and health risk assessment of trace metals in surface soils of Beijing metropolitan, China.

    PubMed

    Chen, Haiyang; Teng, Yanguo; Lu, Sijin; Wang, Yeyao; Wu, Jin; Wang, Jinsheng

    2016-02-01

    Understanding the exposure risks of trace metals in contamination soils and apportioning their sources are the basic preconditions for soil pollution prevention and control. In this study, a detailed investigation was conducted to assess the health risks of trace metals in surface soils of Beijing which is one of the most populated cities in the world and to apportion their potential sources. The data set of metals for 12 elements in 240 soil samples was collected. Pollution index and enrichment factor were used to identify the general contamination characteristic of soil metals. The probabilistic risk model was employed for health risk assessment, and a chemometrics technique, multivariate curve resolution-weighted alternating least squares (MCR-WALS), was applied to apportion sources. Results suggested that the soils in Beijing metropolitan region were contaminated by Hg, Cd, Cu, As, and Pb in varying degree, lying in the moderate pollution level. As a whole, the health risks posed by soil metals were acceptable or close to tolerable. Comparatively speaking, children and adult females were the relatively vulnerable populations for the non-carcinogenic and carcinogenic risks, respectively. Atmospheric deposition, fertilizers and agrochemicals, and natural source were apportioned as the potential sources determining the contents of trace metals in soils of Beijing area with contributions of 15.5%-16.4%, 5.9%-7.7% and 76.0%-78.6%, respectively.

  20. 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.

  1. Source profiles of volatile organic compounds associated with solvent use in Beijing, China

    NASA Astrophysics Data System (ADS)

    Yuan, Bin; Shao, Min; Lu, Sihua; Wang, Bin

    2010-05-01

    Compositions of volatile organic compound (VOC) emissions from painting applications and printing processes were sampled and measured by gas chromatography-mass spectrometry/flame ionization detection (GC-MS/FID) in Beijing. Toluene and C8 aromatics were the most abundant species, accounting for 76% of the total VOCs emitted from paint applications. The major species in printing emissions included heavier alkanes and aromatics, such as n-nonane, n-decane, n-undecane, toluene, and m/p-xylene. Measurements of VOCs obtained from furniture paint emissions in 2003 and 2007 suggest a quick decline in benzene levels associated with formulation changes in furniture paints during these years. A comparison of VOC source profiles for painting and printing between Beijing and other parts of the world showed significant region-specific discrepancies, probably because of different market demands and environmental standards. We conducted the evaluation of the source reactivities for various VOC emission sources. The ozone formation potential (OFP) for unit mass of VOCs source emissions is the highest for paint applications. Substituting solvent-based paints by water-based in Beijing will lead to an OFP reduction of 152,000 tons per year, which is more than 1/4 of the OFPs for VOCs emissions from vehicle exhaust in the city.

  2. [Dynamic changes of ecosystem service value in Pinggu District of Beijing].

    PubMed

    Li, Bo; Song, Xiao-Yuan; Xie, Hua-Lin; Hao, Li-Xia; Zhang, Shu-Hui

    2008-10-01

    Based on the land use/cover data of 1995 and 2004, and by using ecosystem service value per unit area of different terrestrial ecosystem types in China, the dynamic changes of ecosystem service value in Pinggu District of Beijing were analyzed. The results showed that the total ecosystem service value of Pinggu District was decreased from 3.291 x 10(9) yuan in 1995 to 3.044 x 10(9) yuan in 2004, with a change rate of -7.50%. The decrease in the areas of farmland and waters was the primary cause of the loss in ecosystem service function. Aquatic ecosystem had the highest ecological service value per unit area, while forest ecosystem gave the greatest contribution to the total ecosystem service value. The dynamic changes of the ecological service value revealed the conspicuously irrationality of land use structure in the District. The area proportions of forestland, farmland, and waters should be increased, and the conversion from farmland to constructive land should be controlled strictly. As the emergency water source and eco-conservation division of Beijing City, Pinggu District should improve its eco-environment protection and economic development to support the ecological and drinking water source securities of the Capital Beijing.

  3. Source apportionment and health risk assessment of trace metals in surface soils of Beijing metropolitan, China.

    PubMed

    Chen, Haiyang; Teng, Yanguo; Lu, Sijin; Wang, Yeyao; Wu, Jin; Wang, Jinsheng

    2016-02-01

    Understanding the exposure risks of trace metals in contamination soils and apportioning their sources are the basic preconditions for soil pollution prevention and control. In this study, a detailed investigation was conducted to assess the health risks of trace metals in surface soils of Beijing which is one of the most populated cities in the world and to apportion their potential sources. The data set of metals for 12 elements in 240 soil samples was collected. Pollution index and enrichment factor were used to identify the general contamination characteristic of soil metals. The probabilistic risk model was employed for health risk assessment, and a chemometrics technique, multivariate curve resolution-weighted alternating least squares (MCR-WALS), was applied to apportion sources. Results suggested that the soils in Beijing metropolitan region were contaminated by Hg, Cd, Cu, As, and Pb in varying degree, lying in the moderate pollution level. As a whole, the health risks posed by soil metals were acceptable or close to tolerable. Comparatively speaking, children and adult females were the relatively vulnerable populations for the non-carcinogenic and carcinogenic risks, respectively. Atmospheric deposition, fertilizers and agrochemicals, and natural source were apportioned as the potential sources determining the contents of trace metals in soils of Beijing area with contributions of 15.5%-16.4%, 5.9%-7.7% and 76.0%-78.6%, respectively. PMID:26439517

  4. [Composition and Source Apportionments of Saccharides in Atmospheric Particulate Matter in Beijing].

    PubMed

    Liang, Lin-lin; Guenter, Engling; Duan, Feng-kui; Ma, Yong-liang; Cheng, Yuan; Du, Zhen-yu; He, Ke-bin

    2015-11-01

    Based on the newly established high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), the saccharides in PM2.5 and PM10 in Beijing from 2011 - 2012 were quantified. Fourteen saccharides were synchronously detected in the aerosols samples in Beijing, which can be divided into three categories, i. e. anhydrosugar, sugar and sugar alcohol. Anhydrosugar, coming from biomass burning, include levoglucosan, mannosan and galactosan. Sugar and sugar alcohol, emitted by the primary biogenic emission, include glucose, fructose, trehalose, arabitol, mannitol, glycerol, threitol, 2-meythltrtols (2-methylthreitol and 2-methylerythrito), xylitol and inositol. The concentrations of monosaccharide anhydrides in summer and autumn were obviously higher than those in spring and winter, while the concentrations of sugar and sugar alcohol in winter were significantly lower than those in other seasons. The results of positive matrix factorization analysis suggested that saccharides compounds in atmospheric PM in Beijing can be derived from biomass burning, suspended soil or dust, isoprene SOA, as well as direct release of airborne fungal spores and pollen. PMID:26910976

  5. 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.

  6. “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

  7. Heavy metals in urban soils with various types of land use in Beijing, China.

    PubMed

    Xia, Xinghui; Chen, Xi; Liu, Ruimin; Liu, Hong

    2011-02-28

    Heavy metal concentrations of Cd, Cr, Cu, Ni, Pb and Zn were investigated for 127 urban soil samples collected from business area (BA), classical garden (CG), culture and education area (CEA), public green space (PGS), residential area (RA) and roadside area (RSA) in Beijing. The distribution of Cd, Cu, Pb and Zn was mainly affected by anthropogenic sources, with their mean concentrations much higher than the background values of Beijing, while Cr and Ni were from natural sources. Among the 6 types of land use, the concentrations of Cd, Cu, Pb and Zn in CG were significantly higher than those in the other 5 types of land use (p<0.05), which were due to their historical use such as pigments, wood preservation and brassware. For the other 5 types of land use except CG, the mean concentration of Cd in RSA was significantly higher than those in BA, CEA, PGS and RA (p<0.05), suggesting Cd was mainly from traffic sources. The distribution maps revealed that the concentrations of Cu, Pb and Zn showed decreasing trends from the center to the suburb of Beijing, they increased with the age of the urban area.

  8. 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

  9. 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.

  10. 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.

  11. 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

  12. [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

  13. [Optical properties of aerosol during haze-fog episodes in Beijing].

    PubMed

    Yu, Xing-Na; Li, Xin-Mei; Deng, Zen-Grandeng; De, Qing-Yangzong; Yuan, Shuai

    2012-04-01

    The purpose of this study is to investigate the optical properties of aerosol during haze-fog episodes in Beijing. The aerosol optical depth (AOD), Angstrom exponent (alpha), size distribution and single scattering albedo (omega) during haze-fog episodes were analyzed between 2002 and 2008 using AERONENT data. During haze-fog episodes, the aerosol optical depth showed a decreasing trend with wavelengths, and showed high values with an average 1.34 at 440 nm. The magnitude of Angstrom exponent was relatively high during haze-fog episodes and the mean values reached 1.11. The frequency distribution of alpha was up to 94% when alpha > 0.9, indicating the predominance of fine particles during haze-fog episodes in Beijing. The aerosol volume size distributions presented a bimodal structure (fine and coarse modes). The maxima (peaks) radius of fine mode showed an increasing trend with AOD, however, those of coarse mode showed a decreasing trend with AOD. The size distribution showed a distinct difference in dominant mode for the different AOD. The single scattering albedo showed an increasing trend with AOD during haze-fog episodes in Beijing. The mean value of omega was 0.89 at the four wavelengths and the omega exhibited a low sensitivity to wavelengths.

  14. [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

  15. 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

  16. 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

  17. 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.

  18. 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.

  19. 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

    2016-07-20

    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.

  20. Distribution and sources of phthalate esters in the topsoils of Beijing, China.

    PubMed

    Zhang, Zhihuan; He, Guangxiu; Peng, Xuyang; Lu, Ling

    2014-06-01

    Phthalate esters in the topsoil samples collected from Beijing were determined by derivatization and gas chromatography-mass spectrometry techniques. The results showed that diethyl phthalate (DEP), diisobutyl phthalate ester (DIBP), dibutyl phthalate ester (DBP), dibutyl (2-ethyl hexyl) phthalate (DEHP), and dimethyl phthalate (DMP) were found in the topsoils. The total concentrations of the five phthalate esters varied from 2.30 to 24.71 μg g(-1). According to phthalate esters (PAEs) control standards in soil of the USA, the standard exceeding rates of DMP, DBP, and DEHP were 100 %, 100 %, and 4.84 % in soils of Beijing, respectively. The rate of DBP exceeding soil remediation standard was 12.9 %. Overall, concentrations of PAEs in Beijing were at a high level in China. The concentrations of DBP, DEHP, and DIBP were high, and the total concentrations of all the phthalate esters were higher in the areas with intensive human activities than in the other areas, which may be related to the use of phthalate compounds (such as the use of plastic products). The total and individual concentrations of phthalate compounds were relatively low in the areas that used plastic films compared with other samples due to the diffusion of atmospheric motion, categories, and amounts of plastic products and other factors. The greatest contributor may be the usage amount of plastic products in people's daily lives.

  1. [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

  2. 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.

  3. Emergy-based analysis of Beijing-Tianjin-Tangshan region in China

    NASA Astrophysics Data System (ADS)

    Cai, Z. F.; Zhang, L. X.; Zhang, B.; Chen, Z. M.

    2009-12-01

    An emergy-based analysis was conducted for the Beijing-Tianjin-Tangshan urban agglomeration district from perspectives of emergy density, resource structure, environmental pressure and resource use efficiency during the period of 1991-2005. The results showed that Beijing, Tianjin and Tangshan as contiguous regions shared similar characters and evolving trends in certain aspects as emergy intensity and proportion of local renewable resources on the whole. As for the local resources availability, process efficiency and environmental pressure, however, these three cities have significant differences. With comparison of the other cities in China, it is shown that Beijing-Tianjin-Tangshan region has higher environment loading and lower sustainability level though enjoying rapid urbanization process and economic development. This study also suggests that the first priority on economic development competition within urban agglomeration regions may lead to the wasting of resources and redundant construction, while cooperative and rational selection for development pattern are the proper choice for coordinate regional development and long term sustainability to overcome resource restrictions.

  4. [Uncertainty analysis for evaluating methane emissions from municipal solid waste landfill in Beijing].

    PubMed

    Chen, Cao-Cao; Liu, Chun-Lan; Li, Zheng; Wang, Hai-Hua; Zhang, Yan; Wang, Lu

    2012-01-01

    In order to improve the accurate evaluation of CH4 emissions from municipal solid waste landfill in Beijing, FOD-model and Monte Carlo method were conducted. Based on local data, national data and experts' experience, the uncertainty of FOD-model and parameters' sensitivity analysis were identified. And we quantified effect of various parameters on model output. The results showed that 95% probability distribution range of CH4 emission from landfill was (11.8-19.76) x 10(4) t x a(-1) in Beijing. The mean value was 15.58 x 10(4)t x a(-1) with uncertainty range of -24.26% - 26.83%. Among all the parameters MCF (after 2000) showed the greatest impact on landfill CH4 emission in 2008, and its contribution to the uncertainty of emission result was 41.4%. This research can improve the assessment accuracy and quality on CH4 emission from municipal solid waste landfill in Beijing, as providing scientific basis to improve the landfill greenhouse gas inventory and data collection.

  5. 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.

  6. 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.

  7. [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.

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

    PubMed

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

    2011-04-01

    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. PMID:21145723

  9. 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

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

    PubMed

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

    2011-04-01

    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.

  11. Using a mobile laboratory to characterize the distribution and transport of sulfur dioxide in and around Beijing

    NASA Astrophysics Data System (ADS)

    Wang, M.; Zhu, T.; Zhang, J. P.; Zhang, Q. H.; Lin, W. W.; Li, Y.; Wang, Z. F.

    2011-11-01

    Megacities are places with intensive human activity and energy consumption. To reduce air pollution, many megacities have relocated energy supplies and polluted industries to their outer regions. However, regional transport then becomes an important source of air pollution in megacities. To improve air quality before and during the 2008 Beijing Olympics, a wide range of control strategies were implemented, including the relocation of polluting industries. High sulfur dioxide (SO2) concentrations were occasionally observed during this period. Potential sources from southern regions of Beijing were indicated by backward trajectories model and urban/rural stationary measurements, but direct evidence was lacking. Here we used a mobile laboratory to characterize the spatial distribution and regional transport of SO2 to Beijing during the Campaign for Air Quality Research in Beijing and the Surrounding Region (CAREBEIJING)-2008. Among the five days chosen for the case studies during the Olympic air pollution control period, four had high SO2 concentrations (6, 20 August and 3, 4 September 2008) while one had low SO2 concentration (11 September 2008). The average values of SO2 during the low SO2 concentration day were 3.9 ppb, much lower than during the high concentration days (7.8 ppb). This result implied an impact by regional transport from outside Beijing. During these days, we captured transport events of SO2 from areas south of Beijing, with a clear decrease in SO2 concentrations southeast of the 6th to 4th Ring Roads around Beijing and along the 140 km highway from Tianjin to Beijing. The influx of SO2 through the 4th to 6th Ring Roads ranged from 2.1 to 4.6 kg s-1 on 4 September and 0.2 to 1.6 kg s-1 on 20 August 2008. The differences of influx in days were due to the variations of emission changes, transport directions and dilutions. Locally emitted SO2 from a source located along Jingshi Highway outside the southwest section of the 5th Ring Road of Beijing was

  12. Using a mobile laboratory to characterize the distribution and transport of sulfur dioxide in and around Beijing

    NASA Astrophysics Data System (ADS)

    Wang, M.; Zhu, T.; Zhang, J. P.; Zhang, Q. H.; Lin, W. W.; Li, Y.; Wang, Z. F.

    2011-06-01

    Megacities are places with intensive human activity and energy consumption. To reduce air pollution, many megacities have relocated energy supplies and polluted industries to their outer regions. However, regional transport then becomes an important source of air pollution in megacities. To improve air quality before and during the 2008 Beijing Olympics, a wide range of control strategies were implemented, including the relocation of polluting industries. High sulfur dioxide (SO2) concentrations were occasionally observed during this period. Potential sources from southern regions of Beijing were indicated by backward trajectories and urban/rural stationary measurements, but direct evidence was lacking. Here we used a mobile laboratory to characterize the spatial distribution and regional transport of SO2 to Beijing during the Campaign for Air Quality Research in Beijing and the Surrounding Region (CAREBEIJING)-2008. Among the five days chosen for the case studies during the Olympic air pollution control period, four had high SO2 concentrations (6, 20 August and 3, 4 September 2008) while one had low SO2 concentration (11 September 2008). The average values of SO2 during the low SO2 concentration day were 3.9 ppb, much lower than during the high concentration days (7.8 ppb). This result implied an impact by regional transport from outside Beijing. During these days, we captured transport events of SO2 from areas south of Beijing, with a clear decrease in SO2 concentrations southeast of the 6th to 4th Ring Roads around Beijing and along the 140 km highway from Tianjin to Beijing. The influx of SO2 through the 4th to 6th Ring Roads ranged from 2.07 to 4.64 kg s-1 on 4 September and 0.21 to 1.56 kg s-1 on 20 August 2008. Locally emitted SO2 from a source located along Jingshi Highway outside the southwest section of the 5th Ring Road of Beijing was identified using wind field data generated by the Weather Research and Forecasting model and the measured particle size

  13. 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

  14. 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.

  15. Modeling analysis of the seasonal characteristics of haze formation in Beijing

    NASA Astrophysics Data System (ADS)

    Han, X.; Zhang, M.; Gao, J.; Wang, S.; Chai, F.

    2014-09-01

    The air quality modeling system RAMS-CMAQ (Regional Atmospheric Modeling System-Community Multiscale Air Quality), coupled with an aerosol optical property scheme, was applied to simulate the meteorological field, major aerosol components (sulfate, nitrate, ammonium, black carbon, organic carbon, dust, and sea salt), and surface visibility over the North China Plain (NCP) in 2011. The modeled results in February and July 2011 were selected and analyzed to obtain an in-depth understanding of the haze formation mechanism in Beijing for different seasons. The simulation results showed that the visibility was below 10 km for most regions of the NCP, and dropped to less than 5 km over the megacities of Beijing and Tianjin, the whole of Hebei Province, and the northwest part of Shandong Province during pollution episodes in February and July. The heavy mass concentration of PM2.5 ranged from 120 to 300 μg m-3 and was concentrated in the areas with low visibility. The haze formation mechanism in Beijing in winter was different from that in summer. The mass concentration of PM2.5 was higher, and the components more complicated, in winter. While the mass concentration of PM2.5 in summer was lower than that in winter, the mass concentrations of hygroscopic inorganic salts were comparable with those in winter, and the relative humidity was, as expected, higher. Therefore, the water uptake of hygroscopic aerosols played a key role in summer. Moreover, the analysis showed that the influence of the PM2.5 mass burden on visibility was very weak when its value was larger than 100 μg m-3. Only when the mass burden of PM2.5 decreased to a certain threshold interval did the visibility increase rapidly. This indicates that, when emission reduction measures are taken to control haze occurrence, the mass burden of PM2.5 must be cut to below this threshold interval. The relationship between the threshold of haze occurrence and the relative humidity in Beijing was fitted by an

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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.

    2013-04-01

    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 seasonalities 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 study is the first

  1. 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

  2. A study of aerosol properties based on observations of particulate matter from the U.S. Embassy in Beijing, China

    NASA Astrophysics Data System (ADS)

    Mukherjee, Anondo; Toohey, Darin W.

    2016-08-01

    The United States Embassy in Beijing, China publicly released a record of mass concentrations of particulate matter 2.5 µm and smaller in aerodynamic diameter (PM2.5), from April 2008 to the present, measured with a beta attenuation monitor (BAM). We compare these measurements with observations of particulate matter recorded at the Beijing Institute of Atmospheric Physics and observations of visibility recorded at the Beijing Capital International Airport (BCIA) to assess their value as a record of air quality in the greater Beijing metropolitan area. We find that the PM2.5 observations correlate well with the other observations of particulate matter (PM) over the period 1 January-1 February 2013 using a tapered element oscillating microbalance and an aerosol mass spectrometer (AMS), and they exhibit a clear inverse correlation with visibility measured at BCIA. Using inverse visibility as a proxy of radiation extinction, we determine a dry mass extinction efficiency and a dependence of radiation extinction on relative humidity, which is consistent with other studies of polluted urban environments. We deduce a strong degree of homogeneity of particulate pollution across the Beijing metropolitan region and conclude that the U.S. Embassy measurements are a reliable sample of this particulate pollution during periods of photochemical smog. The U.S. Embassy observations of PM2.5 appear to remain consistent throughout the available record and can serve as a useful dataset for studying future trends in particulate matter as China implements ambitious measures to improve air quality in the region.

  3. [Analysis on Regional Characteristics of Air Quality Index and Weather Situation in Beijing and Its Surrounding Cities During the APEC].

    PubMed

    Gao, Qing-xian; Lu, Jun-rong; Wang, Ning; Li, Wen-tao; Gao, Wen-kang; Su, Bu-da

    2015-11-01

    Analysis on the revolution and regional characteristics of air quality by hourly monitored readings from 1 to 15 November 2014 released by Environmental Monitoring Station of China and research of the impacts of weather situation and meteorological elements released by China Meteorological Administration towards air quality of Beijing and its surrounding cities during the Asia-Pacific Economic Cooperation (APEC) indicated that: (1) The air quality was good because of the implementation of mitigation measures, while the Air Quality Index (AQI) increased along with the termination of mitigation measures. Thus it can be seen that mitigation measures made a great contribution to the improvement of air quality of Beijing and its surrounding cities. (2) Affected by thermal inversion layer, AQI of Beijing and its surrounding cities increased quickly during the initial of the implemental of reducing measures which proved that pollutants would accumulate in the context of unfavourable weather, hence the influence of weather situation towards air quality could not be ignored. (3) Although affected by thermal inversion layer, the concentration of pollutants of Beijing was not accumulated to a high degree at the end period of reducing measures, while Tianjin, Tangshan, Baoding and Xingtai suffered from moderate and severe pollution at the same time which further illustrated that the implementation of mitigation measures have made a great contribution to the improvement of air quality in Beijing during APEC.

  4. 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."

  5. Etude Par Spectroscopie Infrarouge des Oxydes Moleculaires Superoxyde de Potassium, Peroxyde de Potassium et Trioxyde de Silicium Isoles EN Matrice D'argon

    NASA Astrophysics Data System (ADS)

    Tremblay, Benoit

    1995-01-01

    A l'aide de la spectroscopie d'absorption infrarouge et de la technique d'isolation en matrice d'argon, nous avons repris l'etude des differents oxydes moleculaires qui se forment lorsque l'oxygene moleculaire se trouve dans des agregats avec du potassium, du silicium et de l'oxyde de silicium SiO. Le choix des oxydes moleculaires KO_2 et K_2O_2 a ete motive par le fait qu'ils ont souvent ete mis en evidence dans tres travaux en physique des surfaces lors de letude du systeme O_2/K/Si. Ces oxydes avaient deja ete identifies par spectroscopie infrarouge en matrice d'argon au debut des annees soixante-dix. Pour KO_2, l'observation des modes nu_2 et nu_3 pour de nombreuses especes isotopiques nous a permis de deduire la longueur de la liaison K-O et de l'angle O-K-O. En effet, la construction d'un champ de force harmonique nous a permis de determiner sa structure et des constantes de force qui reprodusient tres bien les frequences experimentales observees. L'etude de l'oxyde K_2O _2 s'est averee interessante car avant notre travail, seule une vibration avait ete mise en evidence. Nous avons reussi a observer deux nouvelles vibrations fondamentales: une bande infrarouge faible a 185 cm^{-1}, avec les isotopes ^{16}O _2, ^{18}O _2 et ^{16} O^{18}O de l'oxygene, et une autre, activee en infrarouge avec l'isotope ^{16}O^{18 }O a 405 cm^{-1}. Les donnees experimentales etant insuffisantes pour deduire la structure de la molecule, des calculs theoriques avec la methode de la fonctionnelle de la densite ont donne le structure et les vibrations non observees du K _2O_2. Ces donnees supplementaires sont venues completer les resultats experimentaux et nous ont permis de construire un champ de force harmonique avec <=uel nous avons trouve des constantes de force qui reproduisent tres bien les frequences observees. Les calculs theoriques ont monte que K_2O _2 doit etre de structure C_ {rm 2v}, bien que la structure D _{rm 2h} ne puisse pas etre rejetee, puisque qu'il y a un

  6. Comparison of Air Pollution in Metropolises in China (Beijing) and Japan (Osaka and Nagoya) on the Basis of the Levels of Contaminants and Mutagenicity.

    PubMed

    Coulibaly, Souleymane; Minami, Hiroki; Abe, Maho; Furukawa, Nami; Ono, Ryo; Hasei, Tomohiro; Toriba, Akira; Tang, Ning; Hayakawa, Kazuichi; Funasaka, Kunihiro; Asakawa, Daichi; Ikemori, Fumikazu; Watanabe, Masanari; Honda, Naoko; Wakabayashi, Keiji; Watanabe, Tetsushi

    2016-01-01

    Public concern regarding the transport of air pollutants from mainland East Asia to the leeward area by the prevailing westerlies in spring and winter monsoon has been growing in recent years. We collected total suspended particle (TSP) in Beijing, a metropolis of China located windward of Japan, in spring (late February 2011-May 2011) and in winter (November 2012-early February 2013), then analyzed metals, ions, and organic compounds and mutagenicity, and compared the pollution levels with samples collected at two Japanese metropolises (Osaka and Nagoya) during the same periods. The medians of concentration of TSP and other factors in Beijing were much larger than those in the Japanese metropolises. Especially, the concentrations of polycyclic aromatic hydrocarbons (PAHs) were remarkably high in Beijing in winter, and the median of total PAHs concentration in Beijing was 62-63 times larger than that in the Japanese sites. The mutagenicity of TSP from Beijing toward Salmonella typhimurium YG1024, with and without a mammalian metabolic system (S9 mix), was 13-25 times higher than that from the Japanese sites in winter. These results suggest that air pollution levels in Beijing are very high compared with those at the two Japanese metropolises we evaluated. The diagnostic ratios of PAHs and nitrated polycyclic aromatic hydrocarbons (NPAHs) suggest that the major sources of PAHs and NPAHs in Beijing are different from those at the two Japanese sites in winter, and that the major source in Beijing is coal/biomass combustion.

  7. Etude exploratoire des conceptions de la circulation sanguine aupres d'eleves de l'ordre collegial

    NASA Astrophysics Data System (ADS)

    Robitaille, Jean-Marc

    Il existe peu d'etudes sur les conceptions touchant les domaines de la biologie, notamment sur les conceptions de la circulation sanguine Nous avons observe egalement l'absence de recherche menee aupres d'eleves de l'ordre collegial sur cette question. Nous avons voulu combler une lacune en menant une recherche sur les conceptions de la circulation sanguine aupres d'eleves de l'ordre collegial. Pour mener cette recherche nous nous sommes inspires d'une methode developpee par Treagust (1988). Le premier niveau de formulation didactique etablit l'architecture du systeme et la fonction nutritive de la circulation. Le second niveau de formulation didactique decrit et relie les parametres de la dynamique de la circulation et leur relation: Pression, Debit et Resistance. Le troisieme niveau de formulation didactique s'interesse au controle de la circulation du sang dans un contexte d'homeostasie qui implique la regulation de la pression arterielle. Nous avons construit un questionnaire en nous guidant sur les niveaux de formulation didactique et l'analyse des entrevues menees aupres de dix-huit eleves, representatifs de la population cible. Ce questionnaire fut administre a un echantillon de 2300 eleves disperses dans six colleges de la region de Montreal. Notre echantillon comprend des eleves inscrits a des programmes de l'ordre collegial en Sciences de la nature et en Techniques de la sante et qui n'ont pas suivi le cours sur la circulation sanguine. Notre analyse des reponses des eleves de notre echantillon aux questions sur le premier niveau de formulation didactique revele que la majorite des eleves considerent que le systeme circulatoire relie les organes les uns aux autres dans un circuit en serie. Notre analyse revele egalement que la majorite des eleves estiment que les nutriments sont extraits du sang par les organes selon un processus de selection base sur les besoins determines par la fonction de l'organe. Ces besoins sont differents selon les organes qui ne

  8. 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

  9. 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

  10. 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

  11. 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

  12. Etude experimentale des excitations topologiques de l'effet Hall quantique a nu = 1 dans les heterostructures semiconductrices a double puits quantique

    NASA Astrophysics Data System (ADS)

    Charlebois, Serge

    De nombreux travaux theoriques et experimentaux ont ete publies sur les excitations topologiques de gaz electroniques bidimensionnels (GE2D), appellees skyrmions, dans le regime de l'effet Hall quantique a remplissage unitaire. On attend des excitations semblables appellees bimerons dans les systemes formes de deux GE2D couples. Contrairement au cas des GE2D simples, aucune experience n'a, a notre connaissance, presente la mesure d'une propriete specifique aux bimerons. Nous presentons dans cette these des travaux experimentaux ayant pour objectif l'etude d'excitations topologiques dans les heterostructures a double puits quantique. Une manifestation attendue (les bimerons est la presence d'une anisotropie dans la conductivite a travers une constriction. Nous avons concu un dispositif original a point de contact a trois grilles non-coplanaires. Ce dispositif a trois grilles a la particularite de permettre la creation d'une constriction etroite dans le double GE2D tout en permettant l'equilibrage de la densite electronique entre les deux puits dans l'etroit canal de conduction. Nous avons fabrique ce dispositif de taille submicronique par electrolithographie sur des heterostructures a double puits. Les dispositifs ainsi fabriques ont ete etudies a basse temperature (0.3K) et ont montre un fonctionnement conforme aux attentes. Les travaux n'ont pas permis de mettre en evidence une anisotropie de transport revelatrice de l'existence de bimerons. Cette these est a notre connaissance la premiere etude experimentale visant la realisation de l'experience d'anisotropie de transport et est ainsi une contribution significative a l'avancement des connaissances dans ce domaine. Les travaux theoriques que nous presentons ont permis de montrer l'effet des excitations topologiques sur la capacite grille-GE2D du systeme. Ces travaux ouvrent la voie de la detection des bimerons par l'intermediaire de la mesure de la capacite grille-GE2D ou encore de la susceptibilite electrique du

  13. 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

  14. 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.

  15. 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

  16. 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.

  17. Predictors of unprotected sex among men who have sex with men in Beijing, China.

    PubMed

    Li, Xinxu; Shi, Wei; Li, Dongliang; Ruan, Yuhua; Jia, Yujiang; Vermund, Sten H; Zhang, Xiaoxi; Wang, Chen; Liu, Yingjie; Yu, Miao; Xing, Hui; Hong, Kunxue; Shao, Yiming

    2008-01-01

    To estimate the prevalence of HIV and syphilis and to assess the predictors of unprotected anal intercourse (UAI) among men who have sex with men (MSM) in Beijing, a community-based survey recruited MSM in 2005 through internet advertisement, community outreach, and peer referral. Demographic, sexual, and HIV risk behavioral information were collected. Serospecimens were tested for HIV and syphilis infections. Of the 526 participants, 3.2% were HIV-positive, 11.2% syphilis-positive, 50% and 43.3% had UAI with regular and casual sex partners, respectively. Participants practicing UAI with regular male partners were independently associated with lower monthly income (adjusted odds ratio-AOR, 1.7; 95% CI, 1.0-3.0) and encountering male sex partners at bathhouses, public washrooms, and parks (AOR, 2.2; 95% CI, 1.0-4.9). Participants practicing UAI with casual male partners were associated with encountering male sex partners at bathhouses, publics washrooms, and park (AOR, 3.0; 95% CI, 1.8-5.2) and more male sex partners having receptive anal intercourse (AOR, 1.8; 95% CI, 1.1-2.9), and was inversely associated with receiving money for sex with men (AOR, 0.3; 95% CI, 0.2-0.7). Professional male sex workers were less likely to practice UAI in Beijing, suggesting the benefits of educational outreach to date. Further education, condom promotion, and prevention of sexually transmitted infections should be intensified urgently to combat the rising HIV epidemic among MSM in Beijing.

  18. Influences of characteristic meteorological conditions on atmospheric carbonyls in Beijing, China

    NASA Astrophysics Data System (ADS)

    Pang, Xiaobing; Mu, Yujing; Lee, Xinqing; Zhang, Yujie; Xu, Zhu

    2009-08-01

    Atmospheric pollutants are controlled not only by their production rates but also by meteorological conditions. The influences of dust storm, sauna weather (haze with high temperature and high humidity), wet precipitation and wind speed on atmospheric carbonyls in Beijing were investigated. During a severe dust episode (April 17, 2006), the mixing ratios of carbonyls were significantly elevated to 13-27 ppbV from 7 to 13 ppbV in the previous non-dust days (April 15 and 16) with the increasing extents of 38-154%. The accumulating effect and the lower photolysis rate in the dust day may be responsible for the increases of carbonyls' levels. Additionally, the contribution from heterogeneous reactions occurring on dust particles to formaldehyde and acetaldehyde cannot be ruled out. During the period of typical sauna weather, the concentrations of atmospheric carbonyls increased to 18-60 ppbV from 10 to 17 ppbV before the sauna days. The air mass over Beijing during the sauna days was controlled by a subtropical anticyclone and the boundary layer became quite stable, which was beneficial to the rapid accumulation of air pollutants including carbonyls. Wet precipitation was found to be an effective removal process to the atmospheric carbonyls. After one-hour of rain in summer, the total concentrations of atmospheric carbonyls decreased to less than half of that before the rainfall. The similar temporal varying patterns of carbonyls and inorganic ions in rainwater indicated that carbonyls were mainly washed out from the atmosphere into rainwater as inorganic ions were. Strong wind could evidently dilute atmospheric carbonyls and a negative correlation was found between wind speeds and the concentrations of carbonyls in spring in Beijing.

  19. 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.

  20. [The Beijing conference did not meet our expectations. Interview with Sergia Galvan].

    PubMed

    Peguero, J R

    1995-10-01

    An interview with a representative of two women's groups in the Dominican Republic to the International Conference on Women in Beijing expresses disappointment with the achievements of the Conference. The women's movement in the Dominican Republic is at a time of transition in which the importance of working with and influencing other agencies of the civil society and government has become clear. The nongovernmental organizations (NGOs) prepared for the Beijing Conference with a national report evaluating actions for women undertaken in the decade since the previous Conference and recommending additional actions. The document served as a reference for discussions in regional meetings and with specific groups of women. Another document containing the proposals of the Dominican NGOs was created. Representatives of the NGOs participated in discussions with the General Office for Promotion of Women, which officially represented the Dominican Republic in Beijing. In a general sense, the plan of action suggested by the Dominican Republic agreed with that of the women's movement, except that in the important areas of sexual and reproductive rights, the official position was that of the Catholic Church. The outlook for continuing cooperation between the NGOs and the government, represented by the General Office for Promotion of Women, does not appear promising. Such cooperation is not a strategy or policy of the government, and there is considerable resistance within the government to the movement. Latin American and Caribbean women contributed to Conference discussions on the themes of poverty, the impact of structural adjustment programs, reproduction and sexual rights, and violence. The results of the Conference did not meet expectations, largely because of the weight of conservative elements opposed to changes in gender relations. Results should be sought not in the rather weak and underfunded Plan of Action, but in the activities generated by the process.

  1. 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.

  2. Frequencies of blood types A, B, and AB in non-pedigree domestic cats in Beijing

    PubMed Central

    Zheng, Lan; Zhong, Yougang; Shi, Zhensheng; Giger, Urs

    2011-01-01

    Background Blood type A, B, and AB frequencies in domestic cats vary geographically and among breeds. Frequencies of feline blood types in China have not been reported. Objective The purpose of this study was to survey the frequency of blood types in domestic cats in the Beijing area. Methods A total of 262 cats from the city of Beijing were blood-typed using a standard tube agglutination assay. All cats were non-pedigree domestic shorthaired and longhaired cats; purebred cats were excluded. Serum obtained from type B cats and a lectin (Triticum vulgaris) solution served as anti-A and anti-B reagents, respectively. The presence of alloantibodies was also determined in some cats. Results The frequency of blood types was 88.2% type A, 11.4% type B, and 0.4% type AB. The tube assay resulted in 3+ to 4+ agglutination reactions with either the anti-A or anti-B reagents. The one type-AB sample showed 3+ agglutination with both anti-A and anti-B reagents; the plasma of that sample did not react with either type-A or type-B RBCs. Tested type-B cats had strong anti-A antibodies. Conclusions The frequency of blood type B in the Beijing area was relatively high and similar to that reported for other Asian countries and Australia. Blood-typing is recommended to match donors and recipients before transfusion therapy and planned matings to avoid hemolytic transfusion and neonatal isoerythrolysis reactions, respectively, due to blood type incompatibility. PMID:22092346

  3. 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

  4. 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

  5. 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.

  6. 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

  7. 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

  8. 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

  9. 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.

  10. 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

  11. Ozone weekend effects in the Beijing-Tianjin-Hebei metropolitan area, China

    NASA Astrophysics Data System (ADS)

    Wang, Y. H.; Hu, B.; Ji, D. S.; Liu, Z. R.; Tang, G. Q.; Xin, J. Y.; Zhang, H. X.; Song, T.; Wang, L. L.; Gao, W. K.; Wang, X. K.; Wang, Y. S.

    2014-03-01

    The ozone weekend effect (OWE) was first investigated in the metropolitan area of Beijing-Tianjin-Hebei (BTH), China, using in situ measurements from the Atmospheric Environment Monitoring Network from July 2009 to August 2011. The results indicate that there is an obvious weekly periodical variation in the surface ozone concentration. There is a lower ozone concentration from Wednesday to Friday (weekday) and a higher concentration from Saturday to Monday (weekend) at all the locations of the study. NOx also displays a weekly cycle, with the maximum level occurring on weekdays and the minimum level on weekends, especially later on Sunday night and early Monday morning. This pattern may be responsible for the higher concentration of ozone on weekends. Additionally, the vertical variations in O3 and NOx from the 8 m, 47 m, 120 m and 280 m observation platforms on the 325 m Beijing meteorological tower displayed obvious weekly cycles that corresponded to the surface results. A smaller decrease in volatile organic compounds (VOCs; using CO as a proxy) and much lower NOx concentrations on the weekend may lead to higher VOC / NOx ratio, which can enhance the ozone production efficiency in VOC-limited regime areas. Additionally, a clear weekly cycle in the fine aerosol concentration was observed, with maximum values occurring on weekdays and minimum values occurring on weekends. Higher concentrations of aerosol on weekdays can reduce the UV radiation flux by scattering or absorbing, which leads to a decrease in the ozone production efficiency. A significant weekly cycle in UV radiation, consistent with the aerosol concentration, was discovered at the Beijing meteorological tower site (BJT), validating the assumption. A comprehensive understanding of the ozone weekend effect in the BTH area can provide deep insights into controlling photochemical pollution.

  12. 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.

  13. Seasonal and diurnal variations of atmospheric peroxyacetyl nitrate, peroxypropionyl nitrate, and carbon tetrachloride in Beijing.

    PubMed

    Zhang, Gen; Mu, Yujing; Liu, Junfeng; Zhang, Chenglong; Zhang, Yuanyuan; Zhang, Yujie; Zhang, Hongxing

    2014-01-01

    Atmospheric peroxyacetyl nitrate (PAN), peroxypropionyl nitrate (PPN), and carbon tetrachloride (CCl4) were measured from September 2010 to August 2011 in Beijing. PAN exhibited low values from mid-autumn to early spring (October to March) with monthly average concentrations ranging from 0.28 to 0.73 ppbV, and increased from early spring to summer (March to August), ranging from 1.37-3.79 ppbV. The monthly variation of PPN was similar to PAN, with low values (below detection limit to 0.18 ppbV) from mid-autumn to early spring, and a monthly maximum in September (1.14 ppbV). The monthly variation of CCl4 was tightly related to the variation of temperature, exhibiting a minimum in winter (69.3 pptV) and a maximum of 180.6 pptV in summer. Due to weak solar intensity and short duration, PAN and O3 showed no distinct diurnal patterns from morning to night during winter, whereas for other seasons, they both exhibited maximal values in the late afternoon (ca. 15:00 to 16:00 local time) and minimal values during early morning and midnight. Good linear correlations between PAN and PPN were found in autumn (R = 0.91), spring (R = 0.94), and summer (R = 0.81), with slopes of 0.130, 0.222, and 0.133, respectively, suggesting that anthropogenic hydrocarbons dominated the photochemical formation of PANs in Beijing. Positive correlation between PAN and O3 in summer with the low slopes (deltaO3/deltaPAN) ranging from 9.92 to 18.0 indicated serious air pollution in Beijing, and strong negative correlation in winter reflected strong O3 consumption by NO titration and less thermal decompositin of PAN.

  14. Seasonal and diurnal variations of atmospheric peroxyacetyl nitrate, peroxypropionyl nitrate, and carbon tetrachloride in Beijing.

    PubMed

    Zhang, Gen; Mu, Yujing; Liu, Junfeng; Zhang, Chenglong; Zhang, Yuanyuan; Zhang, Yujie; Zhang, Hongxing

    2014-01-01

    Atmospheric peroxyacetyl nitrate (PAN), peroxypropionyl nitrate (PPN), and carbon tetrachloride (CCl4) were measured from September 2010 to August 2011 in Beijing. PAN exhibited low values from mid-autumn to early spring (October to March) with monthly average concentrations ranging from 0.28 to 0.73 ppbV, and increased from early spring to summer (March to August), ranging from 1.37-3.79 ppbV. The monthly variation of PPN was similar to PAN, with low values (below detection limit to 0.18 ppbV) from mid-autumn to early spring, and a monthly maximum in September (1.14 ppbV). The monthly variation of CCl4 was tightly related to the variation of temperature, exhibiting a minimum in winter (69.3 pptV) and a maximum of 180.6 pptV in summer. Due to weak solar intensity and short duration, PAN and O3 showed no distinct diurnal patterns from morning to night during winter, whereas for other seasons, they both exhibited maximal values in the late afternoon (ca. 15:00 to 16:00 local time) and minimal values during early morning and midnight. Good linear correlations between PAN and PPN were found in autumn (R = 0.91), spring (R = 0.94), and summer (R = 0.81), with slopes of 0.130, 0.222, and 0.133, respectively, suggesting that anthropogenic hydrocarbons dominated the photochemical formation of PANs in Beijing. Positive correlation between PAN and O3 in summer with the low slopes (deltaO3/deltaPAN) ranging from 9.92 to 18.0 indicated serious air pollution in Beijing, and strong negative correlation in winter reflected strong O3 consumption by NO titration and less thermal decompositin of PAN. PMID:24649692

  15. Association of Systemic Inflammation with Marked Changes in Particulate Air Pollution in Beijing in 2008

    PubMed Central

    Xu, Xiaohua; Deng, Furong; Guo, Xinbiao; Lv, Peng; Zhong, Mianhua; Liu, Cuiqing; Wang, Aixia; Tzan, Kevin; Jiang, Silis Y.; Lippmann, Morton; Rajagopalan, Sanjay; Qu, Qingshan; Chen, Lung-Chi; Sun, Qinghua

    2012-01-01

    Many studies have linked ambient fine particulate matter (aerodynamic diameters less than 2.5 μm, PM2.5) air pollution to increased morbidity and mortality of cardiovascular diseases in the general population, but the biologic mechanisms of these associations are yet to be elucidated. In this study, we aimed to evaluate the relationship between daily variations in exposure to PM2.5 and inflammatory responses in mice during and for 2 months after the Beijing Olympic Games. Male C57BL/6 mice were exposed to Beijing PM2.5 or filtered air (FA) in 2008 during the 2 months of Beijing Olympic and Paralympic Games, and for 2 months after the end of the Games. During the Games, circulating monocyte chemoattractant protein 1 and interleukin 6 were increased significantly in the PM2.5 exposure group, when compared with the FA control group, although there were no significant inter-group differences in tumor necrosis factor α or interferon γ, or in macrophages, neutrophils or lymphocytes in the spleen or thymus between these 2 groups. However, macrophages were significantly increased in the lung and visceral fat with increasing PM2.5. After the Olympic Games, there were no significant PM2.5-associated differences for macrophages, neutrophils or lymphocytes in the thymus, but macrophages were significantly elevated in the lung, spleen, subcutaneous and visceral fat with increasing PM2.5, and the numbers of macrophages were even higher after than those during the Games. Moreover, the number of neutrophils was markedly higher in the spleen for the PM2.5-exposed- than the FA-group. These data suggest that short-term increases in exposure to ambient PM2.5 leads to increased systemic inflammatory responses, primarily macrophages and neutrophils in the lung, spleen, and visceral adipose tissue. Short-term air quality improvements were significantly associated with reduced overall inflammatory responses. PMID:22617750

  16. Predictors of unprotected sex among men who have sex with men in Beijing, China.

    PubMed

    Li, Xinxu; Shi, Wei; Li, Dongliang; Ruan, Yuhua; Jia, Yujiang; Vermund, Sten H; Zhang, Xiaoxi; Wang, Chen; Liu, Yingjie; Yu, Miao; Xing, Hui; Hong, Kunxue; Shao, Yiming

    2008-01-01

    To estimate the prevalence of HIV and syphilis and to assess the predictors of unprotected anal intercourse (UAI) among men who have sex with men (MSM) in Beijing, a community-based survey recruited MSM in 2005 through internet advertisement, community outreach, and peer referral. Demographic, sexual, and HIV risk behavioral information were collected. Serospecimens were tested for HIV and syphilis infections. Of the 526 participants, 3.2% were HIV-positive, 11.2% syphilis-positive, 50% and 43.3% had UAI with regular and casual sex partners, respectively. Participants practicing UAI with regular male partners were independently associated with lower monthly income (adjusted odds ratio-AOR, 1.7; 95% CI, 1.0-3.0) and encountering male sex partners at bathhouses, public washrooms, and parks (AOR, 2.2; 95% CI, 1.0-4.9). Participants practicing UAI with casual male partners were associated with encountering male sex partners at bathhouses, publics washrooms, and park (AOR, 3.0; 95% CI, 1.8-5.2) and more male sex partners having receptive anal intercourse (AOR, 1.8; 95% CI, 1.1-2.9), and was inversely associated with receiving money for sex with men (AOR, 0.3; 95% CI, 0.2-0.7). Professional male sex workers were less likely to practice UAI in Beijing, suggesting the benefits of educational outreach to date. Further education, condom promotion, and prevention of sexually transmitted infections should be intensified urgently to combat the rising HIV epidemic among MSM in Beijing. PMID:18567448

  17. Size, composition, and strength of ties of personal social support networks among adult people living with HIV/AIDS in Henan and Beijing, China.

    PubMed

    Zhang, Ting; Cao, Weihua; Lv, Jun; Wang, Ning; Reilly, Kathleen Heather; Zhu, Qian; Li, Liming

    2012-05-01

    To characterize the level of personal support available to people living with HIV/AIDS (PLWHA) in Henan and Beijing, China, face-to-face interviews were conducted to collect information on network size, composition, and strength of ties. The number of people as sources of support for participants in Henan varied from 1 to 13 and 1 to 16 in Beijing. In Henan, family members were more likely to provide support than non-relatives and they provided support more frequently; in Beijing non-relatives were more likely to provide support than family members. Family members were closer to PLWHA than non-relatives in both sites, but the closest type of relative and non-relative supporters were different between Henan and Beijing. PLWHA in Henan and Beijing receive considerable social support, but there is still opportunity for additional social support. Efforts should be made to mobilize civil society to provide support for PLWHA in China. PMID:21861194

  18. 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.

  19. Characteristics of PM2.5 concentrations across Beijing during 2013-2015

    NASA Astrophysics Data System (ADS)

    Batterman, Stuart; Xu, Lizhong; Chen, Feng; Chen, Fang; Zhong, Xuefen

    2016-11-01

    High concentrations of particulate matter (PM2.5) and frequent air pollution episodes in Beijing have attracted widespread attention. This paper utilizes data from the new air pollution network in China to examine the current spatial and temporal variability of PM2.5 at 12 monitoring sites in Beijing over a recent 2-year period (April 2013 to March 2015). The long term (2-year) average concentration was 83 μg m-3, well above Chinese and international standards. Across the region, annual average concentrations varied by 20 μg m-3 (25% of the average level), with lower levels in suburban areas compared to periurban and urban areas, which had similar concentrations. The spatial variation in PM2.5 concentrations was associated with several land use and economic variables, including the fraction of vegetated land and building construction activity, which together explained 71% of the spatial variation. Daily air quality was characterized as "polluted" (above 75 μg m-3) on 36-47% of days, depending on site. There were 77 pollution episodes during the study period (defined as two or more consecutive days with Beijing-wide 24-hour average concentrations over 75 μg m-3), and 2 to 5 episodes occurred each month, including summer months. The longest episode lasted 9 days and daily concentrations exceeded 450 μg m-3. Daily PM2.5 levels were autocorrelated (rlag1 = 0.516) and associated with many meteorological variables, including barometric pressure, relative humidity, hours of sunshine, surface and ambient temperature, precipitation and scavenging coefficient, and wind direction. Parsimonious models with meteorological and autoregressive terms explained over 60% of the variation in daily PM2.5 levels. The first autoregressive term and hours of sunshine were the most important variables in these models, however, the latter variable is PM2.5-dependent and thus not an explanatory variable. The present study can serve as a baseline to compare the improved air quality in

  20. 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.

  1. An ion source module for the Beijing Radioactive Ion-beam Facility

    SciTech Connect

    Cui, B. Huang, Q.; Tang, B.; Ma, R.; Chen, L.; Ma, Y.

    2014-02-15

    An ion source module is developed for Beijing Radioactive Ion-beam Facility. The ion source module is designed to meet the requirements of remote handling. The connection and disconnection of the electricity, cooling and vacuum between the module and peripheral units can be executed without on-site manual work. The primary test of the target ion source has been carried out and a Li{sup +} beam has been extracted. Details of the ion source module and its primary test results are described.

  2. 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

  3. 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

  4. 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

  5. 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

  6. [The population growth in the city of Beijing and our present tasks (author's transl)].

    PubMed

    Qian, L J; Xu, B; Huang, S Y

    1980-04-01

    Concern for the rapid population growth since 1949 of China's second largest city, Beijing, is discussed in terms of population control, migration, and rises in the productive development of the city. From 1949 to 1963 the natural rate of population increased from 7.5 to 35.3%; however, after the introduction of a birth control program in 1971, the natural increase of population declined to 4.02% in 1977. From 1949-1978, the average birth rate was 145,000/year while the average death rate was 46,500/year, leaving the annual average increase in population at 98,000. The natural population increased by 2,340,000 from 1949-1978. The massive population growth since 1949 affected the economic development of the city as well as the country. Cultivated land near Beijing increased from 1949-1952, but because of urban development the land for cultivation decreased by 1,527,000 market acres from that available in 1949 (7,965,000 market acres). Population density increased from 430 persons/ square kilometer in 1962 to 506 persons/ square kilometer in 1978. From 1953 to 1978, production and consumption rates fluctuated with a net balance of only 2020 million catties in the 26 years, causing the need for products to be imported from other areas of the country. Unemployment is exacerbated by the lack of jobs and increasing numbers of people. Transportation problems also have developed. New efforts are being made to inform people of population control by the Beijing Population Association begun in 1979, because Beijing's population will continue to increase until 1989 due to the baby boom years during the fifties which created a 2nd boom in the late 1970s as well as the lack of education on population control. Other programs are being developed to, 1) educate people on economical measures of reducing the population, 2) promote governmental departments to improve birth control programs by means of social security services, child health agencies, and nursing schools, 3

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. Sequence and crystallization of influenza virus B/Beijing/1/87 neuraminidase

    SciTech Connect

    Burmeister, W.P.; Daniels, R.S.; Dayan, S.; Gagnon, J.; Cusack, S.; Ruigrok, R.W. )

    1991-01-01

    Influenza B/Beijing/1/87 neuraminidase heads were isolated from virus via trypsin digestion and characterized by PAGE, N-terminal sequencing, electron microscopy, and enzyme activity. The heads were crystallized into two crystal forms; tetragonal plates, like other neuraminidase crystals described before, that diffract to medium resolution (3 A) and a new form consisting of trigonal prisms or needles that diffract to high resolution (at least 2 A). The gene segment coding for neuraminidase was sequenced and compared with the neuraminidase sequence of B/Lee/40. The deduced amino acid sequences for neuraminidase showed only a 7% difference, whereas those for the NB proteins differed by 20%.

  12. 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.

  13. 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

  14. The source identification of ambient aerosols in Beijing, China by multivariate analysis coupled with {sup 14}C tracer

    SciTech Connect

    Xiaoyan Tang; Min Shao; Yuanhang Zhang

    1996-12-31

    Ambient aerosol is one of most important pollutants in China. This paper showed the results of aerosol sources of Beijing area revealed by combination of multivariate analysis models and 14C tracer measured on Accelerator Mass Spectrometry (AMS). The results indicated that the mass concentration of particulate (<100 (M)) didn`t increase rapidly, compared with economic development in Beijing city. The multivariate analysis showed that the predominant source was soil dust which contributed more than 50% to atmospheric particles. However, it would be a risk to conclude that the aerosol pollution from anthropogenic sources was less important in Beijing city based on above phenomenon. Due to lack of reliable tracers, it was very hard to distinguish coal burning from soil source. Thus, it was suspected that the soil source above might be the mixture of soil dust and coal burning. The 14C measurement showed that carbonaceous species of aerosol had quite different emission sources. For carbonaceous aerosols in Beijing, the contribution from fossil fuel to ambient particles was nearly 2/3, as the man-made activities ( coal-burning, etc.) increased, the fossil part would contribute more to atmospheric carbonaceous particles. For example, in downtown Beijing at space-heating seasons, the fossil fuel even contributed more than 95% to carbonaceous particles, which would be potential harmful to population. By using multivariate analysis together with 14C data, two important sources of aerosols in Beijing (soil and coal) combustion were more reliably distinguished, which was critical important for the assessment of aerosol problem in China.

  15. 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.

  16. Real-Time PCR Assay for Rapid Detection of Epidemiologically and Clinically Significant Mycobacterium tuberculosis Beijing Genotype Isolates

    PubMed Central

    Vyazovaya, Anna; Zhuravlev, Viacheslav; Otten, Tatiana; Millet, Julie; Jiao, Wei-Wei; Shen, A-Dong; Rastogi, Nalin; Vishnevsky, Boris; Narvskaya, Olga

    2014-01-01

    Mycobacterium tuberculosis Beijing genotype strains are rapidly disseminating, frequently hypervirulent, and multidrug resistant. Here, we describe a method for their rapid detection by real-time PCR that targets the specific IS6110 insertion in the dnaA-dnaN genome region. The method was evaluated with a geographically and genetically diverse collection representing areas in East Asia and the former Soviet Union in which the Beijing genotype is endemic and epidemic (i.e., major foci of its global propagation) and with clinical specimens. PMID:24523461

  17. Real-time PCR assay for rapid detection of epidemiologically and clinically significant Mycobacterium tuberculosis Beijing genotype isolates.

    PubMed

    Mokrousov, Igor; Vyazovaya, Anna; Zhuravlev, Viacheslav; Otten, Tatiana; Millet, Julie; Jiao, Wei-Wei; Shen, A-Dong; Rastogi, Nalin; Vishnevsky, Boris; Narvskaya, Olga

    2014-05-01

    Mycobacterium tuberculosis Beijing genotype strains are rapidly disseminating, frequently hypervirulent, and multidrug resistant. Here, we describe a method for their rapid detection by real-time PCR that targets the specific IS6110 insertion in the dnaA-dnaN genome region. The method was evaluated with a geographically and genetically diverse collection representing areas in East Asia and the former Soviet Union in which the Beijing genotype is endemic and epidemic (i.e., major foci of its global propagation) and with clinical specimens.

  18. 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.

  19. 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

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. Temporal variations of black carbon during haze and non-haze days in Beijing

    NASA Astrophysics Data System (ADS)

    Liu, Qingyang; Ma, Tangming; Olson, Michael R.; Liu, Yanju; Zhang, Tingting; Wu, Yu; Schauer, James J.

    2016-09-01

    Black carbon (BC) aerosol has been identified as one of key factors responsible for air quality in Beijing. BC emissions abatement could help slow regional climate change while providing benefits for public health. In order to quantify its variations and contribution to air pollution, we systematically studied real-time measurements of equivalent black carbon (eBC) in PM2.5 aerosols at an urban site in Beijing from 2010 to 2014. Equivalent black carbon (eBC) is used instead of black carbon (BC) for data derived from Aethalometer-31 measurement. Equivalent BC concentrations showed significant temporal variations with seasonal mean concentration varying between 2.13 and 5.97 μg m‑3. The highest concentrations of eBC were found during autumn and winter, and the lowest concentrations occurred in spring. We assessed the temporal variations of eBC concentration during haze days versus non-haze days and found significantly lower eBC fractions in PM2.5 on haze days compared to those on non-haze days. Finally, we observed a clear inverse relationship between eBC and wind speed. Our results show that wind disperses PM2.5 more efficiently than eBC; so, secondary aerosols are not formed to the same degree as primary aerosols over the same transport distance during windy conditions.

  5. 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

  6. Variation in initiation condition of debris flows in the mountain regions surrounding Beijing

    NASA Astrophysics Data System (ADS)

    Ma, Chao; Wang, Yu-jie; Du, Cui; Wang, Yun-qi; Li, Yun-peng

    2016-11-01

    Debris flows in the mountain regions surrounding Beijing have been occurring for a long time and have resulted in great economic losses. In this study, 23 rainstorm events, surficial sediments, and debris flow deposits were analyzed to quantify the area's rainfall threshold and to investigate how such conditions may be used to predict debris flow in this region. Rainfall threshold of intensity-duration (I-D) functions after vegetation recovery was higher than before recovery and also higher than I-D levels in other regions where debris flows are closely associated with runoff. Field investigations revealed that surficial sediments were characterized by coarse-grained sediments and that debris flow deposits lacked fine particles. Local debris flows can be triggered by runoff; however, no single standard equation is used to predict the conditions that lead to runoff-triggered debris flow; and commonly used equations give different values. Here, we propose an empirical function that takes into account peak discharge per width and particle diameter. This model should be verified with further investigations so that it can be used as a reference to analyze the conditions that lead to debris flow in the study area. Finally, debris flows may have been related to occasional storms in the study area, which has been experiencing substantially increased temperatures and decreased annual precipitation. This work provides important information about the conditions that initiated debris flow in the Beijing mountain regions in the last few decades.

  7. 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.

  8. 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.

  9. [Estimate of the formation potential of secondary organic aerosol in Beijing summertime].

    PubMed

    Lü, Zi-Feng; Hao, Ji-Ming; Duan, Jing-Chun; Li, Jun-Hua

    2009-04-15

    Fractional aerosol coefficients (FAC) are used in conjunction with measurements of volatile organic compounds (VOC) during ozone episodes to estimate the formation potential of secondary organic aerosols (SOA) in the summertime of Beijing. The estimation is based on the actual atmospheric conditions of Beijing, and benzene and isoprene are considered as the precursors of SOA. The results show that 31 out of 70 measured VOC species are SOA precursors, and the total potential SOA formation is predicted to be 8.48 microg/m3, which accounts for 30% of fine organic particle matter. Toluene, xylene, pinene, ethylbenzene and n-undecane are the 5 largest contributors to SOA production and account for 20%, 22%, 14%, 9% and 4% of total SOA production, respectively. The anthropogenic aromatic compounds, which yield 76% of the calculated SOA, are the major source of SOA. The biogenic alkenes, alkanes and carbonyls produce 16%, 7% and 1% of SOA formation, respectively. The major components of produced SOA are expected to be aromatic compounds, aliphatic acids, carbonyls and aliphatic nitrates, which contribute to 72%, 14%, 11% and 3% of SOA mass, respectively. The SOA precursors have relatively low atmospheric concentrations and low ozone formation potential. Hence, SOA formation potential of VOC species, in addition to their atmospheric concentrations and ozone formation potential, should be considered in policy making process of VOCs control.

  10. 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.

  11. [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.

  12. 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

  13. 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.

  14. [Measurement of atmospheric boundary layer pollutants by mobile lidar in Beijing].

    PubMed

    Wang, Shao-Lin; Xie, Pin-Hua; Hu, Shun-Xing; Wei, He-Li; Hu, Huan-Ling; Xie, Jun; Cao, Kai-Fa; Fang, Xin

    2008-03-01

    The parameters of AML-2 mobile lidar were introduced, which was based on differential absorption principle and designed by our institute. In Yufa of Beijing, the pollutants including O3, NO2, SO2 in atmospheric boundary layer were monitored in August and September of 2006 under different weather conditions. Vertical profile and diurnal variation of concentrations of these pollutants were analyzed. If without the influence of pollution air transport from south region, the concentrations of these pollutants are low under the overcast weather condition. The concentrations of O3 and NO2 decrease with altitude, and this characteristic is not obvious for SO2, but there is a high concentration layer of SO2 near ground (about 0.6km). The quality of atmosphere Beijing is influenced significantly by air transportation from south region, and the altitude of the severe pollution air transport is about 1km to 1.5km in August 23rd to 25th. As a result, the characteristics of vertical profile and daily variation of the pollutants are changed, and the concentrations of O3, NO2, SO2 in atmospheric boundary layer of Yufa area increased obviously.

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. [Genetic variability and phylogenetic analysis of 39 short tandem repeat loci in Beijing Han population].

    PubMed

    Xiuyan, Ruan; Weini, Wang; Yaran, Yang; Bingbing, Xie; Jing, Chen; Yacheng, Liu; Jiangwei, Yan

    2015-07-01

    In this study, we studied the genetic polymorphisms of short tandem repeat (STR) loci from 13 CODIS and 26 non-CODIS system in Beijing Han population for the first time, and established a database of 39 STR loci whose forensic parameters were further evaluated. Our results demonstrated no significant deviation from the Hardy-Weinberg equilibrium of 39 STR loci and no pairwise linkage disequilibrium between them. The power of discriminations, expected heterozygosity, polymorphic information content, and power of exclusion of 39 STR loci ranged from 0.7740-0.9818, 0.6000-0.9350, 0.5317-0.9047 and 0.2909-0.8673. The cumulated discrimination power and cumulative probability of exclusion were 0.999999999999999999999999999999999999999964971 and 0.999999999973878, respectively. Moreover, the genetic distance was calculated based on allele frequency and phylogenetic tree was built using STR loci data from Beijing Han and other 11 Chinese ethnic groups.This study provides important basic data for Chinese forensic DNA database and population genetics database, and has important significance in carrying out forensic individual identification, paternity testing, and population genetic study.

  2. [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.

  3. 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.

  4. Temporal variations of black carbon during haze and non-haze days in Beijing.

    PubMed

    Liu, Qingyang; Ma, Tangming; Olson, Michael R; Liu, Yanju; Zhang, Tingting; Wu, Yu; Schauer, James J

    2016-09-16

    Black carbon (BC) aerosol has been identified as one of key factors responsible for air quality in Beijing. BC emissions abatement could help slow regional climate change while providing benefits for public health. In order to quantify its variations and contribution to air pollution, we systematically studied real-time measurements of equivalent black carbon (eBC) in PM2.5 aerosols at an urban site in Beijing from 2010 to 2014. Equivalent black carbon (eBC) is used instead of black carbon (BC) for data derived from Aethalometer-31 measurement. Equivalent BC concentrations showed significant temporal variations with seasonal mean concentration varying between 2.13 and 5.97 μg m(-3). The highest concentrations of eBC were found during autumn and winter, and the lowest concentrations occurred in spring. We assessed the temporal variations of eBC concentration during haze days versus non-haze days and found significantly lower eBC fractions in PM2.5 on haze days compared to those on non-haze days. Finally, we observed a clear inverse relationship between eBC and wind speed. Our results show that wind disperses PM2.5 more efficiently than eBC; so, secondary aerosols are not formed to the same degree as primary aerosols over the same transport distance during windy conditions.

  5. 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.

  6. 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.

  7. 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.

  8. [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

  9. 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

  10. 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

  11. 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.

  12. Human papillomavirus infection in Beijing, People's Republic of China: a population-based study

    PubMed Central

    Zhao, R; Zhang, W Y; Wu, M H; Zhang, S W; Pan, J; Zhu, L; Zhang, Y P; Li, H; Gu, Y S; Liu, X Z

    2009-01-01

    Background: No recent data exist on human papillomavirus (HPV) infection in Beijing, People's Republic of China. Materials and method We interviewed and examined a representative, randomly selected sample of 5552 sexually active women aged 25–54 years. Cervical cell samples were analysed for HPV DNA by a MY09/11-based PCR assay. Results: Human papillomavirus prevalence was 6.7% overall and 4.8% among women without cervical abnormalities. Of the 21 subtypes identified, HPV16 was the commonest type (2.6% overall; 39.1% of HPV-positive women), followed by HPV 58 (1.0%), 33 (0.8%), 43 (0.7%) and 56 (0.7%). High-risk HPV types predominated in all age groups. Human papillomavirus prevalence was highest in young to middle-aged women. Marital status, number of husband's sexual partners, age at sexual debut and nulligravidity were all associated with being HPV positive. Conclusions: In our survey, HPV 16, HPV 58 and HPV 33 were the most prevalent HPV types in Beijing, indicating the potential for the prophylactic HPV 16/18 vaccine in China. PMID:19862002

  13. Aggregate human health risk assessment from dust of daily life in the urban environment of Beijing.

    PubMed

    Xu, L Y; Shu, X

    2014-04-01

    Because of the high emissions of polycyclic aromatic hydrocarbons (PAHs) into the environment by the increasing number of vehicles in Beijing and the absorption of these PAHs onto particulates, the performance of a preliminary health risk assessment of the aggregate exposure to PAHs of urban citizens in daily life is very important. Urban dust can be used to examine the aggregation of atmospheric particulates from local pollution sources over a long time period and the direct exposure of the urban human population. The environment's correlative with clothing, dining, residing, and traveling in urban daily life was assessed using exposure-receptor-oriented analysis. The multipathway exposure model was used to simulate the lifetime exposure of a female citizen to PAHs in dust. All of the PAH concentrations in dust for each behavior and its correlative environment in Beijing were acceptable because all of the carcinogenic risks of PAHs in the dust were approximately 1.0 × 10(-6). The dominant induced carcinogenic risks in the dust were Benzo(a)pyrene and Dibenzo(a,h)anthracene. The main carcinogenic risk routes for humans were dermal contact and oral intake, which contributed on average 99.78% of the risk. Indoor risk is especially important, as the decoration and height within the building were important impact factors for carcinogenic risk induced by indoor PAHs. For people living in an urban area, a healthy lifestyle includes less decoration per room, living on a low floor, wearing a respirator, and reducing exposed skin area when traveling.

  14. 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

  15. Temporal variations of black carbon during haze and non-haze days in Beijing

    PubMed Central

    Liu, Qingyang; Ma, Tangming; Olson, Michael R; Liu, Yanju; Zhang, Tingting; Wu, Yu; Schauer, James J.

    2016-01-01

    Black carbon (BC) aerosol has been identified as one of key factors responsible for air quality in Beijing. BC emissions abatement could help slow regional climate change while providing benefits for public health. In order to quantify its variations and contribution to air pollution, we systematically studied real-time measurements of equivalent black carbon (eBC) in PM2.5 aerosols at an urban site in Beijing from 2010 to 2014. Equivalent black carbon (eBC) is used instead of black carbon (BC) for data derived from Aethalometer-31 measurement. Equivalent BC concentrations showed significant temporal variations with seasonal mean concentration varying between 2.13 and 5.97 μg m−3. The highest concentrations of eBC were found during autumn and winter, and the lowest concentrations occurred in spring. We assessed the temporal variations of eBC concentration during haze days versus non-haze days and found significantly lower eBC fractions in PM2.5 on haze days compared to those on non-haze days. Finally, we observed a clear inverse relationship between eBC and wind speed. Our results show that wind disperses PM2.5 more efficiently than eBC; so, secondary aerosols are not formed to the same degree as primary aerosols over the same transport distance during windy conditions. PMID:27634102

  16. 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.

  17. 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

  18. 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

  19. 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

  20. Contamination of polycyclic aromatic hydrocarbons (PAHs) in urban soils in Beijing, China.

    PubMed

    Tang, Lily; Tang, Xiang-Yu; Zhu, Yong-Guan; Zheng, Ming-Hui; Miao, Qi-Long

    2005-08-01

    Soil contamination with polycyclic aromatic hydrocarbons (PAHs) is an increasing problem in many countries, including China. An extensive and systematic survey has been undertaken to evaluate the contamination with PAHs of urban soils in Beijing, China. Soil samples were collected from campuses of universities, schools and kindergartens, public squares, fallow land and roadsides, and were analyzed for 16 PAHs by GC-MS. There was a high variability in the total PAHs (SigmaPAHs) concentrations, ranging from less than 366 to 27,825 ng g(-1). The highest SigmaPAHs concentrations were found at roadsides and industrial sites. Soil organic carbon (SOC) is one of the important factors that can influence the concentrations of PAHs in soils. It was found that concentrations of SigmaPAHs were significantly correlated with that of soil organic carbon. To trace the sources of PAHs, the ratios of phenanthrene to anthracene and fluoranthene to pyrene were used to identify pyrogenic and petrogenic sources, respectively. In most cases, PAHs in soils in urban areas of Beijing were pyrogenic. These sources included motor vehicle exhausts, industrial activities and coal burning. These data can be further used to assess the health risk associated with soils polluted with PAHs. PMID:15992927

  1. Mercury contamination in the topsoil and subsoil of urban areas of Beijing, China.

    PubMed

    Li, Xing-Hong; Cheng, Hang-Xin; Zhao, Chuan-Dong; Xu, Xiao-Bai

    2010-08-01

    Mercury contamination is a serious problem in Chinese cities. In the present study, mercury contamination was evaluated in topsoil and subsoil samples collected in an urban area of Beijing. The level of total mercury in topsoil ranged from 12.1 to 8,487 ng g(-1), and a significant correlation (R = 0.58145, p < 0.0001) with polycyclic aromatic hydrocarbons was observed. Higher levels were generally observed in the suburbs and urban centers, with the highest levels being observed in the urban centers. The fraction of water soluble, ion exchangeable, Fe-Mn in the oxide-bound and organic phase was 0.78%, 0.18%, 0.25% and 3.42%, respectively. For subsoils, the level of total mercury ranged from 7.0 to 924.6 ng g(-1), and the higher levels were primarily located in the suburbs. This study showed that mercury has possibly affected the environmental quality of soil and groundwater in urban areas of Beijing.

  2. Microbicide Acceptability among Female Sex Workers in Beijing, China: Results from a Pilot Study

    PubMed Central

    Han, Lin; Lv, Fan; Xu, Peng; Zhang, Guolei; Juniper, Naomi S.

    2009-01-01

    Abstract Objectives To explore attitudes toward hypothetical vaginal microbicides and willingness to use them among female sex workers (FSWs) in a district of Beijing, China, and to identify factors likely to affect acceptability and use of microbicides for HIV prevention among this population. Methods An exploratory cross-sectional study using convenience sampling was conducted. A total of 54 FSWs were recruited from Shijingshan District in Beijing for a face-to-face interview. Main outcome variables were measured by a microbicide acceptability score, perception of HIV/STI risk and self-reported high-risk sexual behaviors, condom use, HIV/STI history, and self-reported experience of vaginal product use. Results Mean score of microbicide acceptability in FSWs was 2.73, with a standard deviation (SD) of 0.46 (ranging from 1 to 4). Acceptability score varied by partner types (p = 0.025), history of HIV testing (p = 0.037), and concern about contracting an STI (p = 0.042). Covert use of microbicides in FSWs with various sexual partners was statistically different (p = 0.001). FSWs preferred to pay for microbicides and to use them covertly. Conclusions In general, FSWs in Shijinghsan District might have a positive response to microbicides across all hypothetical characteristics. Further study is needed for comprehensive understanding of the contextual factors of microbicide use. PMID:19743909

  3. [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

  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. [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.

  6. Temporal variations of black carbon during haze and non-haze days in Beijing.

    PubMed

    Liu, Qingyang; Ma, Tangming; Olson, Michael R; Liu, Yanju; Zhang, Tingting; Wu, Yu; Schauer, James J

    2016-01-01

    Black carbon (BC) aerosol has been identified as one of key factors responsible for air quality in Beijing. BC emissions abatement could help slow regional climate change while providing benefits for public health. In order to quantify its variations and contribution to air pollution, we systematically studied real-time measurements of equivalent black carbon (eBC) in PM2.5 aerosols at an urban site in Beijing from 2010 to 2014. Equivalent black carbon (eBC) is used instead of black carbon (BC) for data derived from Aethalometer-31 measurement. Equivalent BC concentrations showed significant temporal variations with seasonal mean concentration varying between 2.13 and 5.97 μg m(-3). The highest concentrations of eBC were found during autumn and winter, and the lowest concentrations occurred in spring. We assessed the temporal variations of eBC concentration during haze days versus non-haze days and found significantly lower eBC fractions in PM2.5 on haze days compared to those on non-haze days. Finally, we observed a clear inverse relationship between eBC and wind speed. Our results show that wind disperses PM2.5 more efficiently than eBC; so, secondary aerosols are not formed to the same degree as primary aerosols over the same transport distance during windy conditions. PMID:27634102

  7. 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

  8. Characterization of mineral particles in winter fog of Beijing analyzed by TEM and SEM.

    PubMed

    Li, Weijun; Shao, Longyi

    2010-02-01

    Aerosol samples were collected during winter fog and nonfog episodes in Beijing. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were applied to study morphologies, sizes, and compositions of aerosol particles. TEM observation indicates that most mineral particles collected in fog episode are scavenged in fog droplets. Number-size distributions of mineral particles collected in fog and nonfog episodes show two main peaks at the ranges of 0.1-0.3 and 1-2.5 microm, respectively. Based on their major compositions, mineral particles mainly include Si-rich, Ca-rich, and S-rich. Average S/Ca ratio of mineral particles collected in fog episode is 6.11, being eight times higher than that in nonfog episodes. Development mechanism of individual mineral particles in fog droplets is proposed. It is suggested that mineral particles with abundant alkaline components (e.g., "Ca-rich" particles) occurred in air should alleviate acidic degree of fog and contribute to complexity of fog droplets in Beijing.

  9. [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.

  10. 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

  11. 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

  12. 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.

  13. 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

  14. Aging, health and place in residential care facilities in Beijing, China.

    PubMed

    Cheng, Yang; Rosenberg, Mark W; Wang, Wuyi; Yang, Linsheng; Li, Hairong

    2011-02-01

    In recent years, residential care has become an alternative option for elder care in Beijing, China. Little is known, however, about the well-being of elderly residents and the relationship between their health and living in residential care facilities (RCFs). Hence this research aims to understand the well-being of elderly residents in RCFs and how the environment of RCFs affects elderly people's everyday activities and health. The concepts of therapeutic landscapes, active aging, and well-being contribute to understanding the relationships among aging, health, and environment within RCF settings. Qualitative data from 46 in-depth semi-structured interviews with RCF managers, elderly residents, and family members in Beijing were transcribed and analysed using the constant comparative method. The results show that most of the elderly residents are satisfied with their lives in RCFs, but a few of them feel isolated and depressed after their relocation. Each RCF, as a place with its unique physical and social environment, has a significant influence on the elderly residents' physical and psychological well-being. Individual factors such as characteristics of elderly residents, their attitudes on aging and residential care, and family support also play important roles in their adaptation and well-being after relocation from home to RCFs. Although this study focuses on residential care at the local level, it sheds light on future research on geographical and socio-cultural meanings of elder care at local, regional, and national levels in China. PMID:21109338

  15. 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

  16. 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

  17. Residents' preferences for household kitchen waste source separation services in Beijing: a choice experiment approach.

    PubMed

    Yuan, Yalin; Yabe, Mitsuyasu

    2014-12-23

    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.

  18. 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.

  19. The deformation behavior of soil mass in the subsidence region of Beijing, China

    NASA Astrophysics Data System (ADS)

    Tian, F.; Liu, J.-R.; Luo, Y.; Zhu, L.; Yang, Y.; Zhou, Y.

    2015-11-01

    Land subsidence induced by excessive groundwater withdrawal has been a major environmental and geological problem in the Beijing plain area. The monitoring network of land subsidence in Beijing has been established since 2002 and has covered the entire plain area by the end of 2008. Based on data from extensometers and groundwater observation wells, this paper establishes curves of variations over time for both soil mass deformation and water levels and the relationship between soil mass deformation and water level. In addition, an analysis of deformation behavior is carried out for soil mass with various lithologies at different depths depending on the corresponding water level. Finally, the deformation behavior of soil mass is generalized into five categories. The conclusions include: (i) the current rate of deformation of the shallow soil mass is slowing, and most of the mid-deep and deep soil mass continue to compress at a more rapid speed; (ii) the sand strata behaves elastically, while the clay soil mass at different depths is usually characterized by elastic-plastic and creep deformation, which can be considered as visco-elastoplastic.

  20. 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.

  1. Modeling urban storm rainfall runoff from diverse underlying surfaces and application for control design in Beijing.

    PubMed

    Ouyang, Wei; Guo, Bobo; Hao, Fanghua; Huang, Haobo; Li, Junqi; Gong, Yongwei

    2012-12-30

    Managing storm rainfall runoff is paramount in semi-arid regions with urban development. In Beijing, pollution prevention in urban storm runoff and storm water utilization has been identified as the primary strategy for urban water management. In this paper, we sampled runoff during storm rainfall events and analyzed the concentration of chemical oxygen demand (COD), total suspended solids (TSS) and total phosphorus (TP) in the runoff. Furthermore, the first flush effect of storm rainfall from diverse underlying surfaces was also analyzed. With the Storm Water Management Model (SWMM), the different impervious rates of underlying surfaces during the storm runoff process were expressed. The removal rates of three typical pollutants and their interactions with precipitation and underlying surfaces were identified. From these rates, the scenarios regarding the urban storm runoff pollution loading from different designs of underlying previous rates were assessed with the SWMM. First flush effect analysis showed that the first 20% of the storm runoff should be discarded, which can help in utilizing the storm water resource. The results of this study suggest that the SWMM can express in detail the storm water pollution patterns from diverse underlying surfaces in Beijing, which significantly affected water quality. The scenario analysis demonstrated that impervious rate adjustment has the potential to reduce runoff peak and decrease pollution loading.

  2. [Distribution and sources of oxygen and sulfur heterocyclic aromatic compounds in surface soil of Beijing, China].

    PubMed

    He, Guang-Xiu; Zhang, Zhi-Huan; Peng, Xu-Yang; Zhu, Lei; Lu, Ling

    2011-11-01

    62 surface soil samples were collected from different environmental function zones in Beijing. Sulfur and oxygen heterocyclic aromatic compounds were detected by GC/MS. The objectives of this study were to identify the composition and distribution of these compounds, and discuss their sources. The results showed that the oxygen and sulfur heterocyclic aromatic compounds in the surface soils mainly contained dibenzofuran, methyl- and C2-dibenzofuran series, dibenzothiophene, methyl-, C2- and C3-dibenzothiophene series and benzonaphthothiophene series. The composition and distribution of the oxygen and sulfur heterocyclic aromatic compounds in the surface soil samples varied in the different environmental function zones, of which some factories and the urban area received oxygen and sulfur heterocyclic aromatic compounds most seriously. In Beijing, the degree of contamination by oxygen and sulfur heterocyclic aromatic compounds in the north surface soil was higher than that in the south. There were preferable linear correlations between the concentration of dibenzofuran series and fluorene series, as well as the concentration of dibenzothiophene series and dibenzofuran series. The oxygen and sulfur heterocyclic aromatic compounds in the surface soil were mainly derived from combustion products of oil and coal and direct input of mineral oil, etc. There were some variations in pollution sources of different environmental function zones.

  3. 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.

  4. Temporal Patterns in Fine Particulate Matter Time Series in Beijing: A Calendar View

    NASA Astrophysics Data System (ADS)

    Liu, Jianzheng; Li, Jie; Li, Weifeng

    2016-08-01

    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.

  5. 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

  6. Beijing sublineages of Mycobacterium tuberculosis differ in pathogenicity in the guinea pig.

    PubMed

    Kato-Maeda, Midori; 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

    2012-08-01

    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.

  7. 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

  8. Peroxyacetyl nitrate observed in Beijing in August from 2005 to 2009.

    PubMed

    Gao, Tianyu; Han, Li; Wang, Bin; Yang, Guang; Xu, Zhenqiang; Zeng, Limin; Zhang, Jianbo

    2014-10-01

    Measurements of peroxyacetyl nitrate (PAN) were made at a Beijing urban site each August from 2005 to 2009. Over this 5-year period, the average PAN concentration for August in each year increased from 3 (2005) to 11.7μg/m(3) (2007); however, it decreased rapidly in 2008 (4.1μg/m(3)). Generally, the variation over the 5 years showed a rise in the first part of the study period, followed by a decline. We considered two categories of local and regional air masses in this study, which revealed that the PAN concentration in Beijing was affected mainly by southeastern air masses. The August PAN variation was influenced predominantly by local air masses in 2005, but by 2009 regional air masses had become more important. This study showed the level and variation of PAN in the month of August in 5 consecutive years for the first time, and proved that control measures are useful in decreasing photochemical pollution; hence, these measures are probably feasible for other megacities too. Furthermore, this method of analyzing regional and local impacts might be useful for other studies as well. PMID:25288544

  9. 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.

  10. [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

  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. Human papillomavirus type-specific prevalence in women referred for colposcopic examination in Beijing.

    PubMed

    Ding, Xiurong; Liu, Zhizhong; Su, Jianrong; Yan, Donghui; Sun, Wei; Zeng, Zhaoying

    2014-11-01

    Human papillomavirus (HPV) is associated with several disorders of the genital tract, skin, and oropharynx. This study investigated the prevalence of infection by 37 HPV genotypes among women of the Beijing area in China. Cervical specimens from 1,082 patients and 165 healthy controls were tested for HPV genotypes using a chip hybridization assay. Based on the local pathology, patients were divided into cervicitis and cervical lesion groups. Overall HPV infection rates were 30.5% for the cervicitis group and 78.4% for the cervical lesion group; whereas infection rates for high-risk HPV types (i.e., those associated with cervical cancers) were 24.0% and 73.4%, respectively. The most common HPV genotypes were HPV 52, 16, 81, 58, and 18 in healthy controls, HPV 52, 61, 55, 16, and 53 in those with cervicitis, HPV 52, 16, 33, 39, and 58 in cervical intraepithelial neoplasia grade 1, HPV 16, 58, 31, 52, and 33 in cervical intraepithelial neoplasia grade 2 or grade 3, and HPV 16, 33, 18, 52, and 58 in cervical cancer. Established high-risk HPV showed two peaks, in patients aged 30-34 and 55-79 years. In Beijing, HPV 16, 52, 58, and 33 are the most prevalent HPV types in women with cervical lesions, which should affect development of a cervical cancer vaccination for local use.

  13. 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

  14. Early oesophageal cancer: results of a European multicentre survey. Group Européen pour l'Etude des Maladies de l'Oesophage.

    PubMed

    Bonavina, L

    1995-01-01

    Early oesophageal cancer has been extensively studied in Far-Eastern countries, where its prevalence is high. A multicentre survey was conducted within the Groupe Européen pour l'Etude des Maladies de l'Oesophage to analyse results of surgical treatment in patients with disease staged as pTis-T1 N0 M0 according to the tumour node metastasis classification. Of 9743 patients with squamous cell oesophageal carcinoma observed since 1980, 4663 underwent resection; 253 (5.4 per cent) of these fulfilled the criteria for inclusion in the study. The overall mortality rate was 9.1 per cent (23 patients), and was higher after transthoracic than transhiatal oesophagectomy (10.7 versus 6 per cent, P not significant). Pathological examination showed an intraepithelial tumour in 46 patients (18.2 per cent), intramucosal carcinoma in 64 (25.3 per cent) and a submucosal lesion in 143 (56.5 per cent). The overall 5-year survival rate for patients with intraepithelial, intramucosal and submucosal tumours was 92.8, 72.8 and 44.3 per cent respectively. The 5-year survival rate was higher after transthoracic than transhiatal oesophagectomy (66 versus 52 per cent). No survival advantage was observed after either operation in patients with mucosal tumours. Of 21 patients with recurrent disease, 20 had a submucosal lesion. The 5-year survival rate in patients with submucosal tumour was higher after transthoracic than transhiatal oesophagectomy (54.2 versus 25.5 per cent).

  15. 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

  16. [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

  17. 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

  18. 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

  19. Spatio-Temporal Distribution Characteristics and Trajectory Similarity Analysis of Tuberculosis in Beijing, China.

    PubMed

    Li, Lan; Xi, Yuliang; Ren, Fu

    2016-03-07

    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

  20. [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

  1. [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

  2. [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.

  3. 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…

  4. A health-based assessment of particulate air pollution in urban areas of Beijing in 2000-2004.

    PubMed

    Zhang, Minsi; Song, Yu; Cai, Xuhui

    2007-04-15

    Particulate air pollution is a serious problem in Beijing. The annual concentration of particulate matter with aerodynamic diameter less than 10 microm (PM(10)), ranging from 141 to 166 microg m(-3) in 2000-2004, could be very harmful to human health. In this paper, we presented the mortality and morbidity effects of PM(10) pollution based on statistical data and the epidemiological exposure-response function. The economic costs to health during the 5 years were estimated to lie between US$1670 and $3655 million annually, accounting for about 6.55% of Beijing's gross domestic product each year. The total costs were apportioned into two parts caused by: the local emissions and long-range transported pollution. The contribution from local emissions dominated the total costs, accounting on average for 3.60% of GDP. However, the contributions from transported pollution cannot be neglected, and the relative percentage to the total costs from the other regions could account for about 45%. An energy policy and effective measures should be proposed to reduce particulate matter, especially PM(2.5) pollution in Beijing to protect public health. The Beijing government also needs to cooperate with the other local governments to reduce high background level of particulate air pollution.