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Sample records for beijing rp china

  1. 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

  2. Atmospheric mercury monitoring survey in Beijing, China.

    PubMed

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

    2002-07-01

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

  3. 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…

  4. 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

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

    SciTech Connect

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

    2009-05-01

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

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

    PubMed

    Shi, Yun; Howe, Tsu-Hsin

    2016-06-01

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

  7. 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

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  9. 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…

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

    PubMed

    Qi, Jun; Yang, Linsheng; Wang, Wuyi

    2007-01-01

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

  11. 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

  12. 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.

  13. 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

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

    PubMed

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

    1992-02-01

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

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

    PubMed Central

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

    2015-01-01

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

  17. 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.

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

    PubMed

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

    2007-11-01

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

  19. 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.

  20. 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…

  1. 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…

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

    ERIC Educational Resources Information Center

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

    2011-01-01

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

  3. 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

  4. 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

  5. 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

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

    NASA Astrophysics Data System (ADS)

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

    2012-09-01

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

  7. 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

  8. 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

  9. 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.

  10. 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

  11. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2012-12-01

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

  13. 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.

  14. 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

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

    NASA Astrophysics Data System (ADS)

    Dong, Xueling; Liu, Dameng; Gao, Shaopeng

    2013-02-01

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

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

    PubMed

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

    2016-04-01

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

  17. 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

  18. 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

  19. 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.

  20. 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

  1. 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.

  2. 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

  3. 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

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  5. New attempts on increasing economic gains in the development of geothermal resources in Beijing, China

    SciTech Connect

    Zheng, K.

    1997-12-31

    The development of geothermal resources in the city of Beijing and its surrounding suburbs has been made possible by investments from companies in the surrounding Provinces of China. The development of these geothermal deposits has created a market for hot spring real estate. The real estate has been developed into comprehensive projects for recreation and vacation resorts, in addition to, heath care centers and greenhouse farming. This new attempt to develop these geothermal resources has increased the economic growth of the area and interest in geothermal expansion.

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

    PubMed

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

    2010-09-15

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

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

    PubMed

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

    2015-10-01

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

  8. 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

  9. 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

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

    NASA Astrophysics Data System (ADS)

    Mi, S.; Wen, X.

    2012-12-01

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

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

    NASA Astrophysics Data System (ADS)

    Zheng, Sheng; Pozzer, Andrea; Cao, Chunxiang

    2014-05-01

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

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

    PubMed

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

    2015-01-01

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

  14. 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

  15. On-road emission characteristics of VOCs from light-duty gasoline vehicles in Beijing, China

    NASA Astrophysics Data System (ADS)

    Cao, Xinyue; Yao, Zhiliang; Shen, Xianbao; Ye, Yu; Jiang, Xi

    2016-01-01

    This study is the third in a series of three papers aimed at characterizing the VOC emissions of vehicles in Beijing. In this study, 30 light-duty vehicles fueled with gasoline were evaluated using a portable emission measurement system (PEMS) as they were driven on a predesigned, fixed test route. All of the tested vehicles were rented from private vehicle owners and spanned regulatory compliance guidelines ranging from Pre-China I to China IV. Alkanes, alkenes, aromatics and some additional species in the exhaust were collected in Tedlar bags and analyzed using gas chromatography/mass spectrometry (GC-MS). Carbonyls were collected on 2,4-dinitrophenyhydrazine (DNPH) cartridges and analyzed using high-performance liquid chromatography (HPLC). Overall, 74 VOC species were detected from the tested vehicles, including 22 alkanes, 6 alkenes, 1 alkyne, 16 aromatics, 3 cyclanes, 10 halohydrocarbons, 12 carbonyls and 4 other compounds. Alkanes, aromatics and carbonyls were the dominant VOCs with weight percentages of approximately 36.4%, 33.1% and 17.4%, respectively. The average VOC emission factors and standard deviations of the Pre-China I, China I, China II, China III and China IV vehicles were 469.3 ± 200.1, 80.7 ± 46.1, 56.8 ± 37.4, 25.6 ± 11.7 and 14.9 ± 8.2 mg/km, respectively, which indicated that the VOC emissions significantly decreased under stricter vehicular emission standards. Driving cycles also influenced the VOC emissions from the tested vehicles. The average VOC emission factors based on the travel distances of the tested vehicles under urban driving cycles were greater than those under highway driving cycles. In addition, we calculated the ozone formation potential (OFP) using the maximum incremental reactivity (MIR) method. The results of this study will be helpful for understanding the true emission levels of light-duty gasoline vehicles and will provide information for controlling VOC emissions from vehicles in Beijing, China.

  16. 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

  17. 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

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

    NASA Astrophysics Data System (ADS)

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

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

  19. Modern Tectonic Deformation in the Active Basin-and-Range Province Northwest of Beijing, China

    NASA Astrophysics Data System (ADS)

    Mi, Suting; Wen, Xueze

    2013-04-01

    Our study region is the northwest of Beijing, northern north China. The most typical extensional active tectonic area of the China continent, called the active basin-and-range province northwest of Beijing, exist there. This active tectonic province is made up of several NE-trending Quaternary graben basins and horst ranges between basins. An about 1500-year-long written historical record has suggested that there have been no major earthquakes with magnitude 7 or greater occurred in most of the study region since AD 512. So, the characteristic of modern tectonic deformation of the study region and its implication for the future seismic potential of major earthquakes are important scientific issues. In this study, based on data of regional GPS station velocities and active tectonics, combining relocated earthquake distribution, we make a preliminary analysis on the characteristic of the modern tectonic deformation of the study region. We design three zones across deferent segments of the active basin-and-range province to analyze both the present tectonic deformation from the GPS velocity profiles and the major fault's downward-extents from the relocated hypocenters. Our analyses reveal that: (1) Significant NNW-ward and SSE-ward horizontal extension exists on different segments of the active basin-and-range province northwest of Beijing at rates of 2 to 3mm /yr, accompanied with right-lateral shear deformation at 1 to 2mm/yr. (2) On the western and middle segments of the active basin and range province, most of the total horizontal extension and shear deformation happen in the width from the Huangqihai basin to the Datong-Yanggao basin , suggesting that some major faults in this width could have had relatively-high strain build-up. (3) It is possible that one or more basement detachment belts exist under the active basins, and it or they possibly dip(s) southeastern-ward. (4) The modern tectonic extensional rate is up to 2 to 3mm /yr in the study region. However

  20. 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

  1. An evaluation of atmospheric Nr pollution and deposition in North China after the Beijing Olympics

    NASA Astrophysics Data System (ADS)

    Luo, X. S.; Liu, P.; Tang, A. H.; Liu, J. Y.; Zong, X. Y.; Zhang, Q.; Kou, C. L.; Zhang, L. J.; Fowler, D.; Fangmeier, A.; Christie, P.; Zhang, F. S.; Liu, X. J.

    2013-08-01

    North China is known for its large population densities and rapid development of industry and agriculture. Air quality around Beijing improved substantially during the 2008 Summer Olympics. We measured atmospheric concentrations of various Nr compounds at three urban sites and three rural sites in North China from 2010 to 2012 and estimated N dry and wet deposition by inferential models and the rain gauge method to determine current air conditions with respect to reactive nitrogen (Nr) compounds and nitrogen (N) deposition in Beijing and the surrounding area. NH3, NO2, and HNO3 and particulate NH4+ and NO3-, and NH4+-N and NO3--N in precipitation averaged 8.2, 11.5, 1.6, 8.2 and 4.6 μg N m-3, and 2.9 and 1.9 mg N L-1, respectively, with large seasonal and spatial variability. Atmospheric Nr (especially oxidized N) concentrations were highest at urban sites. Dry deposition of Nr ranged from 35.2 to 60.0 kg N ha-1 yr-1, with wet deposition of Nr of 16.3 to 43.2 kg N ha-1 yr-1 and total deposition of 54.4-103.2 kg N ha-1 yr-1. The rates of Nr dry and wet deposition were 36.4 and 33.2% higher, respectively, at the urban sites than at the rural sites. These high levels reflect the occurrence of a wide range of Nr pollution in North China and suggest that further strict air pollution control measures are required.

  2. On-road emission characteristics of VOCs from diesel trucks in Beijing, China

    NASA Astrophysics Data System (ADS)

    Yao, Zhiliang; Shen, Xianbao; Ye, Yu; Cao, Xinyue; Jiang, Xi; Zhang, Yingzhi; He, Kebin

    2015-02-01

    This paper is the first in our series of papers aimed at understanding the volatile organic compound (VOC) emissions of vehicles in Beijing by conducting on-board emission measurements. This paper focuses on diesel vehicles. In this work, 18 China III diesel vehicles, including seven light-duty diesel trucks (LDDTs), four medium-duty diesel trucks (MDDTs) and seven heavy-duty diesel trucks (HDDTs), were examined when the vehicles were driven on predesigned fixed test routes in Beijing in China using a portable emissions measurement system (PEMS). Tedlar bag sampling and 2,4-dinitrophenyhydrazine (DNPH) cartridge sampling were used to collect VOC species, and gas chromatography-mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC) were used to analyze these samples. We obtained the VOC emission factors and relative compositions for diesel trucks of different sizes under different driving patterns. In total, 64 VOC species were quantified in this study, including 25 alkanes, four alkenes, 13 aromatics, 13 carbonyls and nine other compounds. The emission factors of the total VOCs based on mileage traveled for HDDTs were higher than those of LDDTs and MDDTs. Carbonyls, aromatics and alkanes were the dominant VOC species. Carbonyls accounted for 42.7%-69.2% of the total VOCs in the three types of tested diesel trucks. The total VOC emission factors of the tested vehicles that were driven on non-highway routes were 1.5-2.0 times higher than those of the vehicles driven on the highway. As for the OFP calculation results, with increased vehicle size, the ozone formation potential presented an increasing trend. Among the VOC components, carbonyls were the primary contributor to OFP. In addition, the OFPs under non-highway driving cycles were 1.3-1.7 times those under highway driving cycles. The results of this study will be helpful in improving our understanding of VOCs emitted from on-road diesel trucks in China.

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

    NASA Astrophysics Data System (ADS)

    Zheng, Sheng; Cao, Chunxiang; Singh, Ramesh

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

  4. 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

  5. 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.

  6. Levels of polybrominated diphenyl ethers and hexabromocyclododecane in the atmosphere and tree bark from Beijing, China.

    PubMed

    Hu, Jicheng; Jin, Jun; Wang, Ying; Ma, Zhaohui; Zheng, Wanjing

    2011-06-01

    Air samples in four seasons at one site and tree bark samples from four districts were determined to investigate seasonal variation and regional distribution of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) in Beijing, China. The total concentrations of PBDEs (∑PBDE) and HBCD (∑HBCD) were in the range of 57-470 and 20-1800 pg m(-3) in the atmosphere, respectively. The ∑PBDE and ∑HBCD concentrations were significantly influenced by the total suspended particulate matter in atmosphere. The total concentrations of PBDEs and HBCD in tree bark samples were in the range of 99-3700 and 26-3400 ng g(-1) lipid weight. It was found that regional distribution of PBDEs and HBCD was related to the function of each district. In addition, the study found that weeping willow bark was an ideal atmospheric PBDEs and HBCD passive sampler. Finally, atmospheric levels of BDE-209 and HBCD at tree bark sampling districts were estimated via applying an established bark/air partitioning model, which had been verified by the measured concentrations in tree bark and atmosphere in Beijing. PMID:21546059

  7. Generation amount prediction and material flow analysis of electronic waste: a case study in Beijing, China.

    PubMed

    Liu, Xianbing; Tanaka, Masaru; Matsui, Yasuhiro

    2006-10-01

    The draft legislation on e-waste prepared by the Chinese national government assigns management responsibility to local governments. It is an urgent task for the municipal government to plan an effective system as soon as possible to divert the e-waste flow from the existing informal e-waste recycling processes. This paper presents a case study implemented in Beijing, the capital city of China, with the purpose of predicting the amount of obsolete equipment for five main kinds of electronic appliances from urban households and to analyse the flow after the end of their useful phase. The amount to be handled was 885,354 units in 2005 and is predicted to double by 2010. Due to consumption growth and the expansion of urbanization it is estimated that the amount will increase to approximate 2,820,000 units by 2020: 70% of the obsolete appliances will be awaiting collection for possible recycling, 7% will be stored at the owner's home for 1 year on average and 4% will be discarded directly and enter the municipal solid waste collecting system. The remaining items will be reused for about 3 years on average after the change of ownership. The results of this study will assist the waste management authorities of Beijing to plan the collecting system and facilities needed for management of e-waste generated in the near future. PMID:17121115

  8. 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

  9. Estimation of carbon dioxide flux and source partitioning over Beijing, China.

    PubMed

    Song, Tao; Wang, Yuesi; Sun, Yang

    2013-12-01

    The magnitude and partitioning of carbon dioxide emission from the urban area in Beijing, China was estimated based on a statistical approach. Results showed that the urban surface is a net source of CO2 to atmosphere. The main sources of CO2 are vehicles, which accounted for 75.5% and 38.9% of CO2 emission in summer and winter, respectively. At midday in summer, the CO2 uptake of -0.034 mg/(m2 x sec) indicated that vegetation is an important sink of CO2 in summer. Comparison between the annual emission rates of CO2 from the statistical approach and that directly measured by the eddy covariance technique implies that a bottom-up emission approach is a viable means to estimate CO2 emission in an urban area. PMID:24649674

  10. Risk assessment and water safety plan: case study in Beijing, China.

    PubMed

    Ye, Bixiong; Chen, Yuansheng; Li, Yonghua; Li, Hairong; Yang, Linsheng; Wang, Wuyi

    2015-06-01

    Two typical rural water utilities in Beijing, China were chosen to describe the principles and applications of water safety plans (WSP), to provide a methodological guide for the actual application and improve the quality of rural drinking water quality, and to establish an appropriate method for WSP applied in rural water supply. Hazards and hazardous events were identified and risk assessment was conducted for rural water supply systems. A total of 13 and 12 operational limits were defined for two utilities, respectively. The main risk factors that affect the water safety were identified in water sources, water processes, water disinfection systems and water utility management. The main control measures were strengthening the water source protection, monitoring the water treatment processes, establishing emergency mechanisms, improving chemical input and operating system management. WSP can be feasibly applied to the management of a rural water supply. PMID:26042982

  11. Characterization of on-road vehicle emission factors and microenvironmental air quality in Beijing, China

    NASA Astrophysics Data System (ADS)

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

    In this paper, we report the results and analysis of a recent field campaign in August 2007 investigating the impacts of emissions from transportation on air quality and community concentrations in Beijing, China. We conducted measurements in three different environments, on-road, roadside and ambient. The carbon monoxide, black carbon and ultrafine particle number emission factors for on-road light-duty vehicles are derived to be 95 g kg -1-fuel, 0.3 g kg -1-fuel and 1.8 × 10 15 particles kg -1-fuel, respectively. The emission factors for on-road heavy-duty vehicles are 50 g kg -1-fuel, 1.3 g kg -1-fuel and 1.1 × 10 16 particles kg -1-fuel, respectively. The carbon monoxide emission factors from this study agree with those derived from remote sensing and on-board vehicle emission testing systems in China. The on-road black carbon and particle number emission factors for Chinese vehicles are reported for the first time in the literature. Strong traffic impacts can be observed from the concentrations measured in these different environments. Most clear is a reflection of diesel truck traffic activity in black carbon concentrations. The comparison of the particle size distributions measured at the three environments suggests that the traffic is a major source of ultrafine particles. A four-day traffic control experiment conducted by the Beijing Government as a pilot to test the effectiveness of proposed controls was found to be effective in reducing extreme concentrations that occurred at both on-road and ambient environments.

  12. Molecular characterization and antibiotic resistance of clinical Streptococcus dysgalactiae subsp. equisimilis in Beijing, China.

    PubMed

    Lu, Binghuai; Fang, Yujie; Huang, Lei; Diao, Baowei; Du, Xiaoli; Kan, Biao; Cui, Yanchao; Zhu, Fengxia; Li, Dong; Wang, Duochun

    2016-06-01

    Streptococcus dysgalactiae subsp. equisimilis (SDSE) is presently considered as a human pathogen associated with clinical infection. We characterized 56 SDSE isolates collected from two tertiary hospitals in Beijing, China. Sixteen distinct emm types/subtypes were detected, dominated by stG245.0 (32.1%), stG652.0 (10.7%), stG6.1 (10.7%) and stG485.0 (10.7%), and a novel stG840.0 variant type was identified. All isolates possessed virulence genes of sagA and scpA, and most carried slo (98.2%), ska (98.2%) and speG(dys) (35.7%). By multilocus sequence typing (MLST) analysis, 17 individual sequence types (STs) were distinguished, including 7 newly-identified STs (26.8% of isolates), of which ST127 (30.4%), ST7 (12.5%) and ST44 (10.7%) dominated. Meanwhile, pulsed-field gel electrophoresis (PFGE) analysis revealed 33 pattern types (PTs), which were further combined into 16 pattern clusters (PCs), and 59.3% of isolates were distributed into 2 dominant PCs. Notably, emm types had both close relationship and consistency with STs and PFGE PCs. Furthermore, of 56 SDSE isolates, the predominant antibiotic resistances were erythromycin (71.4%), clindamycin (71.4%) and tetracycline (60.7%). Correspondingly, the prevalent resistance genes of macrolide and tetracycline were erm(B) (78.6%) and tet(M) (73.2%). In addition, multiple point mutations of parC, one of fluoroquinolone resistance genes, were observed (accounting for 75%), and were divided into 12 types, with parC 07 as the predominant type. Our data suggested the wide molecular diversity and distinctive regional features of SDSE from clinical infection in Beijing, China. PMID:26925701

  13. Source of Personal Exposure to PM2.5 among College Students in Beijing, China

    NASA Astrophysics Data System (ADS)

    Xie, Qiaorong; Zhu, Xianlei; Li, Xiang; Hui, Fan; Fu, Xianqiang; Zhang, Qiangbin

    2015-04-01

    The health risk from exposure to airborne particles arouses increasing public concern in Beijing, a megacity in China, where concentration of PM2.5 frequently exceeds the guideline values of World Health Organization (WHO). To investigate daily exposure to PM2.5, a personal exposure study was conducted for college students. The purpose of this study was to measure the daily PM2.5 personal exposures of students, to quantify the contributions of various microenvironments to personal exposure since students spend more than 85% of their time indoors, and to apportion the contributions of PM2.5 indoors origin and outdoor origin. In this work, a total of 320 paired indoor and outdoor PM2.5 samples were collected at eight types of microenvironments in both China University of Petroleum (suburban area) and Tsinghua University (urban area). The microenvironments were selected based on the time-activity diary finished by 1500 students from both universities. Simultaneously, the air exchange rate was measured in each microenvironment. PM2.5, elements, inorganic ions and polycyclic aromatic hydrocarbons in the samples were determined. The peak concentrations were observed in dinning halls, whereas PM2.5 in dormitories was the largest contributor to personal exposure because students spend more than half of a day there. Furthermore, source apportionment by positive matrix factorization (PMF) will be carried out to understand the source of personal exposure to PM2.5. Especially, efforts will be put on determing the contributions of primary combustion, secondary sulfate and organics, secondary nitrate, and mechanically generated PM, which present different infiltration behavior and are indoor PM2.5 of ambient origin, with help of air exchange rate data. The results would be benefit for refining the understanding of the contribution of PM2.5 of ambient (outdoor) origin to the daily PM2.5 personal exposures. Acknowledgments:This study has been funded by Beijing Municipal Commission

  14. Impacts of climate change on spring flower tourism in Beijing, China

    NASA Astrophysics Data System (ADS)

    Wang, Huanjiong

    2016-04-01

    The beauty of blooming flowers causes spring to be one of the most picturesque and pleasant seasons in which to travel. However, the blooming time of plant species are very sensitive to small changes in climate. Therefore, recent climate change may shift flowering time and, as a result, may affect timing of spring tourism for tourists. In order to prove this assumption, we gathered data of first flowering date and end of flowering date (1963-2014) for 49 common ornamental plants in Beijing, China. In addition, we used the number of messages (2010-2014) posted on Sina Weibo (one of the most popular microblogs sites in China, in use by well over 30% of internet users, with a market penetration similar to the United States' Twitter) to indicate the tourist numbers of five scenic spots in Beijing. These spots are most famous places for seeing spring flowers, including the Summer Palace, Yuyuantan Park, Beijing Botanical Garden, Jingshan Park, Dadu City Wall Relics Park. The results showed that the number of species in flower starts to increase in early spring and peaks in middle spring, and then begins to decrease from late spring. The date when the number of species in flower peaks can be defined as best date of spring flower tourism, because on this day people can see blooming flowers of most plant species. The best date of spring flower tourism varied from March 31 to May 1 among years with a mean of April 20. At above scenic spots characterized by the beauty of blooming flowers, tourist numbers also had a peak value during spring. Furthermore, peak time of tourist numbers derived from Weibo varied among different years and was related to best date of spring flower tour derived from phenological data. This suggests that the time of spring outing for tourists is remarkably attracted by flowering phenology. From 1963 to 2014, the best date of spring flower tour became earlier at a rate of 1.6 days decade-1, but the duration for spring flower tour (defined as width at

  15. Observation of a Dust Storm during 2015 Spring over Beijing, China

    NASA Astrophysics Data System (ADS)

    Lv, Y.; Li, D.; Li, Z.; Chen, X.; Xu, H.; Liu, Z.; Qie, L.; Zhang, Y.; Li, K.; Ma, Y.

    2015-12-01

    Dust events bring significant impacts on the regional environment, human health and even climate. There are four major dust explosion areas in the world, such as North America, Australia, Central Asia and Middle East. Located in the Central Asia, North China has a severe desertification because of deforestation and excessive population growth. Beijing is at the fork of three dust transmission paths in Chin, which makes it a dust-prone region for a long history especially in spring. Thanks to the improvement of the ecological environment in Mongolia, the number of dust weather in recent years reduced significantly than before. However, as the spring coming earlier for the relatively high temperature, a severe dust weather process happened suddenly on March 28, 2015 following with the long-term hazy weather, which up to the highest intensity in the nearly two years. A set of ground-based observations for this serious dust event were adopted in this paper. The ground-based remote sensing station is equipped with an automatic CIMEL lidar and an AERONET sun-photometer. Aerosol optical depth (AOD) and aerosol size distribution were measured by sun-photometer. AOD of dust reached 2.0 at 532nm, which was much larger than clear days. And there was an obvious trend that coarse mode increases more significantly and quickly than fine mode when a dust storm occurs. At the same time, data provided by the air quality monitoring and analysis platform of China shown that the PM10 concentration was larger than 1000μg/m3 and PM10 made important contribution to the high AQI. Lidar observation clearly shown the dust spread very tall (higher than 1km) when the dust storm occurrence. After the dust dissipating, the planetary boundary layer roughly from 0 to 3km, aerosol has a very widely vertical distribution. The AOD based on sun-photometer were taken as a constraint, 65 sr were retrieved and analyzed. And the extinction coefficients indicated that the dust had been dissipation near

  16. Prevalence of Human Papillomavirus Genotypes Among Women With High-Grade Cervical Lesions in Beijing, China.

    PubMed

    Xiao, Meizhu; Xu, Qiuxiang; Li, Hongyan; Gao, Huiqiao; Bie, Yachun; Zhang, Zhenyu

    2016-01-01

    The aim of the study is to investigate the prevalence of high-risk human papillomavirus (hr-HPV) genotypes among Han women with high-grade cervical lesions in Beijing, China.Cervical cell specimens from patients with histopathologically confirmed cervical lesions at 7 hospitals in Beijing were examined with a validated HPV kit for 13 hr-HPV genotypes during the study period. The patients were divided into a low-grade cervical lesions group (cervical intraepithelial neoplasia grade 1, CIN1) and a high-grade cervical lesions group (CIN2+, including cervical intraepithelial neoplasia grade 2, CIN2; cervical intraepithelial neoplasia grade 3, CIN3; squamous cervical cancer, SCC; and adenocarcinoma of the cervix, ACC) based on the histopathology results.A total of 2817 eligible patients were enrolled, including 610 cases identified as CIN1 and 2207 as CIN2+. The hr-HPV positive rates in the CIN1 and CIN2+ groups were 78.2% (477/610) and 93.3% (2060/2207), respectively. The most frequently detected genotypes were HPV16, 58, 52 and18 in the CIN1 group and HPV16, 58, 33, and 52 in the CIN2+ group, in descending order of prevalence. In addition, the prevalence of HPV18 among the patients with ACC was 28.6% (14/49), significantly >7.2% (54/752) prevalence among the SCC patients (P < 0.001). Additionally, significantly more women in the CIN2+ group had multiple infections compared with those in the CIN1 group (38.1% and 24.9%, respectively; P < 0.001). However, as the cervical lesion grade increased, the prevalence of multiple hr-HPV infections gradually deceased to 44.2% in the CIN2 patients, 36.7% in the CIN3 patients, and 35.3% in the cervical cancer (CC) patients, which included SCC and ACC patients. In cases of multiple hr-HPV infections in the CIN2+ group, double infections accounted for ∼76.6%, and HPV16+58, HPV16+52, and HPV16+18 were the most common combinations, in descending order. The most frequent combination for triple infections was HPV16+58+31, with

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

    NASA Technical Reports Server (NTRS)

    Guo, Song; Zhou, Xiuji; Zhang, Xiachun

    1994-01-01

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

  18. Ten-year Pollution Characteristics of Particulate-associated Polycyclic Aromatic Hydrocarbons in Beijing, China

    NASA Astrophysics Data System (ADS)

    Zhu, Xianlei; Deng, Changjiang; Biandan, Luobu; Fu, Xianqiang; Mu, Xilong

    2015-04-01

    Polycyclic aromatic hydrocarbons (PAHs) are well-known air pollutants of health concern. However, they are not listed as routinely measured pollutants in China, in spite of benzo[a]pyrene (BaP) being included in the National Ambient Air Quality Standard (NAAQS). Thus, very limited continuous measurements are available for PAHs, which would hinder the understanding of long-term pollution characteristics of PAHs in context of rapid development of economy and intensive urbanization in China. To investigate annual variation and its causes of airborne particulate-associated PAHs, a total of 18 PAHs (including 16 USEPA priority species) in PM10 and PM2.5 were measured in Beijing, the capital and one of megacities of China, for a decade (from the year of 2004 to 2013) with meteorological data simultaneously recorded. The long-term measurements of PAHs showed significant annual and seasonal variations for the total concentration of PAHs (ΣPAH18) and individual PAH species. The ΣPAH18 in PM10 was highest in 2010 and lowest in 2006. Likewise, the ΣPAH18 in PM2.5 reached the highest level in 2010 and dropped to the lowest level in 2005. The annual concentration varied insignificantly for 2- and 3-ring PAHs, were relatively high in the year of 2004, 2007 and 2010 for 4-ring PAHs, and increased gradually with year for 5- to 7-ring PAHs, the markers of motor vehicle emission. As for seasonal variation, the concentrations in winter (heating period) was higher than those in summer, while concentrations in spring and autumn ranked in the middle. As for BaP, one of criteria pollutants, its concentration exceeded NAAQS of China in winter. Source apportionment by factor analysis suggested the contributions of coal combustion, vehicle emissions, fugitive dust and straw burning. Especially, the great contributions of coal combustion and vehicle emission were also supported by diagnostic ratios. The backward trajectories showed air mass crossing polluted cities and transporting in low

  19. 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…

  20. 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

  1. 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

  2. Assessing the Capacity of Plant Species to Accumulate Particulate Matter in Beijing, China

    PubMed Central

    Mo, Li; Ma, Zeyu; Xu, Yansen; Sun, Fengbin; Lun, Xiaoxiu; Liu, Xuhui; Chen, Jungang; Yu, Xinxiao

    2015-01-01

    Air pollution causes serious problems in spring in northern China; therefore, studying the ability of different plants to accumulate particulate matter (PM) at the beginning of the growing season may benefit urban planners in their attempts to control air pollution. This study evaluated deposits of PM on the leaves and in the wax layer of 35 species (11 shrubs, 24 trees) in Beijing, China. Differences in the accumulation of PM were observed between species. Cephalotaxus sinensis, Euonymus japonicus, Broussonetia papyriferar, Koelreuteria paniculata and Quercus variabilis were all efficient in capturing small particles. The plants exhibiting high amounts of total PM accumulation (on leaf surfaces and/or in the wax layer), also showed comparatively high levels of PM accumulation across all particle sizes. A comparison of shrubs and trees did not reveal obvious differences in their ability to accumulate particles based on growth form; a combination of plantings with different growth forms can efficiently reduce airborne PM concentrations near the ground. To test the relationships between leaf traits and PM accumulation, leaf samples of selected species were observed using a scanning electron microscope. Growth forms with greater amounts of pubescence and increased roughness supported PM accumulation; the adaxial leaf surfaces collected more particles than the abaxial surfaces. The results of this study may inform the selection of species for urban green areas where the goal is to capture air pollutants and mitigate the adverse effects of air pollution on human health. PMID:26506104

  3. Bright and Not-So-Bright Prospects for Women in Physics in China-Beijing

    NASA Astrophysics Data System (ADS)

    Wu, Ling-An; Yang, Zhongqin; Ma, Wanyun

    2009-04-01

    Science in China-Beijing is enjoying a healthy increase in funding year by year, so the prospects for physicists are also bright. However, employment discrimination against women, formerly unthinkable, is becoming more and more explicit as the country evolves toward a market economy. Some recruitment notices bluntly state that only men will be considered, or impose restrictions upon potential female candidates. Female associate professors in many institutions are forced to retire at age 55, compared with 60 for men. This double-pinching discrimination against both younger and older women threatens to lead to a "pincer" effect, more serious than the "scissors" effect. Indeed, the ratio of senior-level women physicists in general has dropped significantly in recent years in China. Ironically, the number of female students applying for graduate studies is on the rise, as it is becoming increasingly difficult for them to compete with men in the job market with just an undergraduate degree. The Chinese Physical Society has made certain efforts to promote the image of women physicists, but it will take time and effort to reverse the trend.

  4. Enumeration and characterization of campylobacter species from retail chicken carcasses in Beijing, China.

    PubMed

    Bai, Yao; Cui, Shenghui; Xu, Xiao; Li, Fengqin

    2014-11-01

    Epidemiological data have implicated contaminated raw or undercooked chicken as primary vehicles of Campylobacter transmission to humans. Risk assessment relating to Campylobacter contamination of poultry products in China is frequently hampered by the lack of quantitative data. In this study, whole chicken carcasses (n=240) were collected from the retail markets of Beijing. The level of Campylobacter contamination was enumerated by the plate-counting method. The representative Campylobacter isolates were characterized for antimicrobial resistance. Selected representative isolates were further analyzed by the multilocus sequencing typing method for genetic relatedness. Overall, 26.3% (63/240) of the retail whole chicken carcasses were contaminated by Campylobacter, and the values ranged from 2.5 to 7050 colony-forming units (CFU)/g. The 50th percentile of Campylobacter value was 45 CFU/g in chicken carcass. Multidrug-resistant profiles were observed in 33 (39.2%) C. jejuni isolates (from 27 chicken carcasses) and 57 (86.4%) C. coli isolates (from 30 chicken carcasses). One dominant ST (ST6322) and one dominant clonal complex (CC828) consisting of multidrug-resistant C. coli isolates were identified. Our findings showed a high prevalence of Campylobacter contamination in retail chicken carcasses, which could be a source of exposure to multidrug-resistant isolates for consumers. This study provided baseline enumeration data for the quantitative risk assessment and evaluation of new control measures of Campylobacter contamination in retail chicken products in China. PMID:25238587

  5. Organochlorine pesticide residuals in chickens and eggs at a poultry farm in Beijing, China.

    PubMed

    Tao, S; Liu, W X; Li, X Q; Zhou, D X; Li, X; Yang, Y F; Yue, D P; Coveney, R M

    2009-02-01

    Chicken organs, animal feed, droppings, and ambient air were sampled at a farm in Beijing to determine the concentrations of hexachlorocyclohexane isomers (HCHs) and dichlorodiphenyltrichloroethane and metabolites (DDTs). Mean fresh weight concentrations of HCHs and DDTs were 0.122+/-0.061 ng/g and 0.051+/-0.038 ng/g in the muscles. These values are 1-2 orders of magnitude lower than those reported in China in 1980. Contaminated feed was the main source of HCHs and DDTs. Only 12.8% of HCH and 3.3% of DDT of the amount consumed were excreted. Accumulated quantities of HCHs and DDTs increased during growth. However, concentrations of HCHs and DDTs did not increase because of dilution from rapid growth. Based on the observed residual levels in mature chicken and the average diet of residents of China, the contributions from chicken and egg consumption to per capita daily intake of HCHs and DDTs were 487% and 88% of those of fish consumption. PMID:18963306

  6. Relative efficiency and productivity: a preliminary exploration of public hospitals in Beijing, China

    PubMed Central

    2014-01-01

    Background Third-grade hospitals in Beijing have been rapidly developing in capacity and scale for many years. These hospitals receive a large number of patients, and ensuring their efficient operation is crucial in meeting people’s healthcare needs. In this context, a study of their relative efficiency and productivity would be helpful to identify the driving factors and further improve their performance. Methods After a review of literature, the current numbers of open beds and employees were selected as input variables. The number of outpatient and emergency visits and the number of discharged patients were selected as output variables. A total of 12 third-grade Class A general public hospitals in Beijing were selected for a preliminary study. The panel data from 2006–2009 were collected by the National Institute of Hospital Administration, Ministry of Health of P.R. China. Descriptive analysis and data envelopment analysis were used to analyze the data using Stata 10.0 and DEAP(V2.1) software. Results In the 2006–2009 period, descriptive results show that sample hospitals continuously expanded their capacity and scale, with growth rate of total revenue being the highest among all variables. The DEA results show that the average annual growth rate of productivity was 26.7%, and the rates were 47.3%, 21.3% and 13.8% respectively for two consecutive years. The average annual growth rate of technological change was 28.3%, and the rates were 49.4%, 21.5% and 16.4% respectively for two consecutive years. The average annual growth rate of technical efficiency change was -1.3%, and the rates were -1.4%, -0.02% and -2.2% respectively for two consecutive years. Conclusions The sample hospitals in Beijing experienced substantial productivity growth, but annual growth rates were declining. Substantial technological change was the main contributor to the growth. Although some hospitals exhibited improvements in technical efficiency, there was a slight decline in

  7. Polybrominated diphenyl ethers in atmosphere from three different typical industrial areas in Beijing, China.

    PubMed

    Dong, Yuan; Fu, Shan; Zhang, Yongfei; Nie, Haifeng; Li, Zheng

    2015-03-01

    Three common industries that cause polybrominated diphenyl ethers (PBDEs) pollution in Beijing, China, are solid waste incineration, chemical manufacturing, and coal-fired thermal power generation. This study was conducted to determine both the concentrations and profiles of 42 PBDEs in gaseous and particulate matter (including PM2.5, PM2.5-10, and total suspended particulate (TSP)) from the major industries listed above at three sites in Beijing. The total concentration of PBDEs (defined as the sum of 42 congeners in gas and TSP) were 60.5-216 pg m(-3) at the solid waste incineration plant, 71.8-7500 pg m(-3) at the chemical plant, and 34.4-454 pg m(-3) at the coal-fired thermal power plant. The results indicate that the components of PBDE in gas were similar between three industrial sites, and the dominant congener was tri-BDEs. However, in particulate matter, the dominant BDEs were different between the three sites, possibly because they originated from different sources. In particulate matter, the dominant PBDEs were penta-BDEs at the solid waste incineration plant, deca-BDE at the coal-fired thermal power plant, and tetra-BDEs and deca-BDE at the chemical plant. Source analysis revealed that PBDE contamination might be associated with the use of different commercial PBDE flame-retardant mixtures. Results from a previous risk assessment indicated that the risk to human health was low. However, results from this study suggest that there is a potential threat associated with human exposure to PBDEs for the residents near these industrial sites. PMID:25491762

  8. Relating urban surface temperature to surface characteristics in Beijing area of China

    NASA Astrophysics Data System (ADS)

    Liu, Weidong; Lu, Liping; Ye, Caihua; Liu, Yonghong

    2009-10-01

    The surface environment and the thermal infrared information of remote sensing have been widely used to study urban climate. In this paper, the Landsat Thematic Mapper (TM) data acquired in 2008 were applied to study the relationship between urban surface temperature and surface characteristics within the Beijing 5th ring road area of China. The thermal band data of TM combined with classification-based surface emissivity were utilized to estimate land surface temperature (LST). Meanwhile, surface characteristics parameters, such as the Normalized Difference Vegetation Index (NDVI), the Modified Normalized Difference Water Index (MNDWI), the Normalized Difference Building Index (NDBI) and the Normalized Difference Bareness Index (NDBaI) were calculated according to related arithmetic respectively. The quantitative relationship between LST and NDVI, MNDWI, NDBI and NDBaI were investigated according to urban main land use/cover types (water body, vegetation and built-up surfaces). The results showed there were negative correlations between LST and NDVI, MNDWI for vegetation and built-up land use/cover types, positive correlations between LST and NDBI, NDBaI for vegetation and built-up land use/cover types. In general, in the area 5th ring road of Beijing the distribution of NDVI, MNDWI and NDBI directly defined the distribution of LST. For built-up land use/cover type, the NDVI was small, However, NDBI and LST were high. While in the area with more water and vegetation, the NDVI and MNDWI were high and LST was small. There were obvious correlation between LST and urban surface characteristics.

  9. Health benefit evaluation of the energy use scenarios in Beijing, China.

    PubMed

    Pan, Xiaochuan; Yue, Wei; He, Kebin; Tong, Shilu

    2007-03-15

    Air pollution is one of the important causal factors for excess cardiorespiratory deaths and diseases. However, little information is available on health gains from clean energy usage in developing countries. In this study the expected population exposed to air pollutants was estimated under the different energy use scenarios by the year 2010, 2020 and 2030, respectively, in the urban area of Beijing, China. The concentration-response functions between air pollutants and the health endpoints were established using meta-analysis and regression models. The decreased cardiorespiratory deaths and diseases of the exposed population were predicted as the health benefits from air pollution reduction. We used daily measurements of particulate matter less than 10 mum in aerodynamic diameter (PM(10)) and sulphate dioxide (SO(2)) as air pollution indicators. The percentage of population exposed to higher level of PM(10) will be decreased significantly under the clean energy use scenario than that under the Baseline Scenario (i.e., business-as-usual scenario). Compared with the Baseline Scenario there will be, by 2010, 2020, and 2030, respectively, a decrease of 29-152, 30-212 and 39-287 acute excess deaths; and 340-1811, 356-2529 and 462-3424 chronic excess deaths associated with the reduction of PM(10) level; also a decrease of 237-331, 285-371 and 400-554 short-term excess deaths associated with the decrease of SO(2) level. Meanwhile, the number of respiratory and cardiovascular hospital admissions, outpatient visits to internal and paediatrics departments, total emergency room visits and asthma attacks will be remarkably reduced with the reduction of air pollution. Energy structure improvement could reduce ambient air pollution and produce substantial health benefits to the population in Beijing. These findings may have significant implications for other metropolitan cities, particularly in developing countries. PMID:17289123

  10. Evaluation of fungal spore characteristics in Beijing, China, based on molecular tracer measurements

    NASA Astrophysics Data System (ADS)

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

    2013-03-01

    PM2.5 (particulate matter with aerodynamic diameters less than 2.5 μm) and PM10 (particulate matter with aerodynamic diameters less than 10 μm) samples were collected by high-volume air samplers simultaneously at a rural site and an urban site in Beijing, China. Various carbohydrates were quantified by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), including the sugar alcohols mannitol and arabitol, recently proposed as molecular tracers for fungal aerosol. The annual average concentrations of arabitol in PM2.5 and PM10 at the urban site were 7.4 ± 9.4 and 21.0 ± 20.4 ng m-3, and the respective mannitol concentrations were 10.3 ± 9.5 and 31.9 ± 26.9 ng m-3. During summer and autumn, higher arabitol and mannitol levels than during spring and winter were observed in coarse particles, probably due to different dominant sources of fungal spores in different seasons. In the dry season (i.e., winter and spring) in Beijing, probably only the suspension from exposed surfaces (e.g., soil resuspension, transported dust, etc) can be regarded as the main sources for fungal aerosols. On the other hand, in summer and autumn, fungal spores in the atmosphere can be derived from more complex sources, including plants, vegetation decomposition and agricultural activity, such as ploughing; these fungal spore sources may contribute more to coarse PM. Moreover, statistical analysis according to typical seasonal patterns, including a dry season (December 2010 to March 2011) and a wet season (July to September 2011), revealed different variations of fungal spores in different seasons. Although fungal spore levels at rural sites were reported to be consistently higher than those at urban sites in other studies, our findings showed the opposite pattern, indicating a high abundance of fungal spores in the urban area of this Chinese megacity.

  11. Prevalence and molecular characterization of Cryptosporidium spp. and Giardia duodenalis in dairy cattle in Beijing, China.

    PubMed

    Li, Fuhuang; Wang, Haiyan; Zhang, Zhenjie; Li, Junqiang; Wang, Chenrong; Zhao, Jinfeng; Hu, Suhui; Wang, Rongjun; Zhang, Longxian; Wang, Ming

    2016-03-30

    822 fecal samples from cattle in six areas of Beijing were examined with microscopy for Cryptosporidium oocysts and Giardia cysts. The overall infection rates for Cryptosporidium spp. and Giardia duodenalis were 2.55% and 1.09%, respectively. Cryptosporidium was only detected in calves and heifers, whereas G. duodenalis was found in all age groups. Cryptosporidium spp. were characterized with a PCR-restriction fragment length polymorphism analysis and DNA sequence analysis of the small subunit (SSU) rRNA gene. Two Cryptosporidium species were identified: Cryptosporidium parvum (n=12) and Cryptosporidium andersoni (n=9). Six C. parvum isolates were successfully subtyped with the gp60 gene and three subtypes were detected: IIdA19G1 (n=1), IIdA17G1 (n=1), and IIdA15G1 (n=4). Subtype IIdA17G1 is reported for the first time in cattle worldwide. Nine G. duodenalis isolates were analyzed by sequencing the triosephosphate isomerase (tpi) gene, and only G. duodenalis assemblage E was identified. Therefore, the predominance of C. parvum detected in calves was identical to that found in the Xinjiang Uyghur and Ningxia Hui Autonomous Regions, but differed considerably from that in Henan, Heilongjiang, and Shannxi Provinces. In contrast, the predominance of G. duodenalis assemblage E was more or less similar to its predominance in other areas of China or countries. Our findings confirm the unique character of the C. parvum IId subtypes in China. More systematic studies are required to better understand the transmission of Cryptosporidium and G. duodenalis in cattle in China. PMID:26921041

  12. Control Costs, Enhance Quality, and Increase Revenue in Three Top General Public Hospitals in Beijing, China

    PubMed Central

    Zhao, Lue-Ping; Yu, Guo-Pei; Liu, Hui; Ma, Xie-Min; Wang, Jing; Kong, Gui-Lan; Li, Yi; Ma, Wen; Cui, Yong; Xu, Beibei; Yu, Na; Bao, Xiao-Yuan; Guo, Yu; Wang, Fei; Zhang, Jun; Li, Yan; Xie, Xue-Qin; Jiang, Bao-Guo; Ke, Yang

    2013-01-01

    Background With market-oriented economic and health-care reform, public hospitals in China have received unprecedented pressures from governmental regulations, public opinions, and financial demands. To adapt the changing environment and keep pace of modernizing healthcare delivery system, public hospitals in China are expanding clinical services and improving delivery efficiency, while controlling costs. Recent experiences are valuable lessons for guiding future healthcare reform. Here we carefully study three teaching hospitals, to exemplify their experiences during this period. Methods We performed a systematic analysis on hospitalization costs, health-care quality and delivery efficiencies from 2006 to 2010 in three teaching hospitals in Beijing, China. The analysis measured temporal changes of inpatient cost per stay (CPS), cost per day (CPD), inpatient mortality rate (IMR), and length of stay (LOS), using a generalized additive model. Findings There were 651,559 hospitalizations during the period analyzed. Averaged CPS was stable over time, while averaged CPD steadily increased by 41.7% (P<0.001), from CNY 1,531 in 2006 to CNY 2,169 in 2010. The increasing CPD seemed synchronous with the steady rising of the national annual income per capita. Surgical cost was the main contributor to the temporal change of CPD, while medicine and examination costs tended to be stable over time. From 2006 and 2010, IMR decreased by 36%, while LOS reduced by 25%. Increasing hospitalizations with higher costs, along with an overall stable CPS, reduced IMR, and shorter LOS, appear to be the major characteristics of these three hospitals at present. Interpretations These three teaching hospitals have gained some success in controlling costs, improving cares, adopting modern medical technologies, and increasing hospital revenues. Effective hospital governance and physicians' professional capacity plus government regulations and supervisions may have played a role. However, purely

  13. [Molecular epidemiological characteristics of HIV-1 strains isolated from newly diagnosed MSM subjects (2006-2010) in Beijing, China].

    PubMed

    Ye, Jing-Rong; Zang, Wan-Chun; Su, Xue-Li; Lu, Hong-Yan; Hao, Ming-Qiang; Xin, Ruo-Lei; Chen, Guo-Min; He, Xiong; Zeng, Yi

    2014-03-01

    This study aims to analyze the molecular epidemiological characteristics of HIV-1 strains prevailing among men who have sex with men (MSM) in Beijing, China. The pol gene fragments from 250 newly diagnosed HIV-1-infected MSM individuals during 2006-2010 in Beijing were amplified by RT-nested PCR, sequenced, and phylogenetically analyzed. HIV-1 pol gene from 189 individuals were amplified and analyzed; 81 (42. 9%), 3 (1. 6%), 2 (1.0%), 88 (46. 6%), and 15 (7.9%) individuals were infected with HIV-1 subtypes B, B', C, CRF01_AE, and CRF07_BC, respectively. The subtypes B and CRF01_AE could both be grouped into two clusters, and CRFO7_BC strains shared high homology and were presumed to originate from a common ancestor. The HIV-1 circulating in MSM in Beijing had a lower genetic diversity than in heterosexuals. The HIV-1 epidemic (2006-2010) in MSM in Beijing was actually a rapid spread of HIV-1 CRF01 AE and B, or rather native strains of the two viruses. PMID:24923166

  14. Geo-spatial Hotspots of Hemorrhagic Fever with Renal Syndrome and Genetic Characterization of Seoul Variants in Beijing, China

    PubMed Central

    Zuo, Shu-Qing; Fang, Li-Qun; Zhan, Lin; Zhang, Pan-He; Jiang, Jia-Fu; Wang, Li-Ping; Ma, Jia-Qi; Wang, Bing-Cai; Wang, Ri-Min; Wu, Xiao-Ming; Yang, Hong; Cao, Zhi-Wei; Cao, Wu-Chun

    2011-01-01

    Background Hemorrhagic fever with renal syndrome (HFRS) is highly endemic in mainland China, and has extended from rural areas to cities recently. Beijing metropolis is a novel affected region, where the HFRS incidence seems to be diverse from place to place. Methodology/Principal Findings The spatial scan analysis based on geographical information system (GIS) identified three geo-spatial “hotspots” of HFRS in Beijing when the passive surveillance data from 2004 to 2006 were used. The Relative Risk (RR) of the three “hotspots” was 5.45, 3.57 and 3.30, respectively. The Phylogenetic analysis based on entire coding region sequence of S segment and partial L segment sequence of Seoul virus (SEOV) revealed that the SEOV strains circulating in Beijing could be classified into at least three lineages regardless of their host origins. Two potential recombination events that happened in lineage #1 were detected and supported by comparative phylogenetic analysis. The SEOV strains in different lineages and strains with distinct special amino acid substitutions for N protein were partially associated with different spatial clustered areas of HFRS. Conclusion/Significance Hotspots of HFRS were found in Beijing, a novel endemic region, where intervention should be enhanced. Our data suggested that the genetic variation and recombination of SEOV strains was related to the high risk areas of HFRS, which merited further investigation. PMID:21264354

  15. Radon Concentrations in Drinking Water in Beijing City, China and Contribution to Radiation Dose

    PubMed Central

    Wu, Yun-Yun; Ma, Yong-Zhong; Cui, Hong-Xing; Liu, Jian-Xiang; Sun, Ya-Ru; Shang, Bing; Su, Xu

    2014-01-01

    222Rn concentrations in drinking water samples from Beijing City, China, were determined based on a simple method for the continuous monitoring of radon using a radon-in-air monitor coupled to an air-water exchanger. A total of 89 water samples were sampled and analyzed for their 222Rn content. The observed radon levels ranged from detection limit up to 49 Bq/L. The calculated arithmetic and geometric means of radon concentrations in all measured samples were equal to 5.87 and 4.63 Bq/L, respectively. The average annual effective dose from ingestion of radon in drinking water was 2.78 μSv, and that of inhalation of water-borne radon was 28.5 μSv. It is concluded that it is not the ingestion of waterborne radon, but inhalation of the radon escaping from water that is a substantial part of the radiological hazard. Radon in water is a big concern for public health, especially for consumers who directly use well water with very high radon concentration. PMID:25350007

  16. Occurrence and removal of antibiotics in a municipal wastewater reclamation plant in Beijing, China.

    PubMed

    Li, Wenhui; Shi, Yali; Gao, Lihong; Liu, Jiemin; Cai, Yaqi

    2013-07-01

    In this study, we investigated the occurrences and fates of eight quinolones (QNs), nine sulfonamides (SAs), and five macrolides (MCs) in a wastewater reclamation plant (WRP) in Beijing, China. Among all the 22 antibiotics considered, quinolones were the dominant antibiotics in all samples (4916ngL(-1) in influents, 1869ngL(-1) in secondary effluents, 123ngL(-1) in tertiary effluents, and 9200μgkg(-1) in sludge samples), followed by sulfonamides (2961ngL(-1) in influents, 1053ngL(-1) in secondary effluents, 25.9ngL(-1) in tertiary effluents, and 63.7μgkg(-1) in sludge samples) and macrolides (365ngL(-1) in influents, 353ngL(-1) in secondary effluents, 24.7ngL(-1) in tertiary effluents, and 32.7μgkg(-1) in sludge samples). The removal efficiencies of the target antibiotics were limited (-32 to 78%) in the conventional treatment. This study indicated that quinolones were mainly removed from the secondary clarifier, and sulfonamides were degraded in the oxic tank; while macrolides were considered as persistent during the conventional treatment. After the advance treatment, the target antibiotics could be effectively removed at high rates (85-100%), and the risks of antibiotic contamination significantly decreased. However, risk assessment showed that the risk of ofloxacin and erythromycin on organisms in recycled water needed further investigations. PMID:23399307

  17. Investigation of parabens in commercial cosmetics for children in Beijing, China.

    PubMed

    Wang, Ping; Li, Jie; Tian, Hanmei; Ding, Xiaojing

    2013-01-01

    Parabens are one of the most common preservatives in cosmetics. Because allergenicity and cytotoxicity potential values are major aspects of preservative safety and parabens are xenoestrogens, safety levels of parabens have been restricted in "Hygienic Standard for Cosmetics" (2007 edition) by the Ministry of Public Health of China, and a high-performance liquid chromatography (HPLC) for the simultaneous determination of parabens is recommended. To investigate whether the commonly used parabens in children's cosmetics were at a safety level, 105 cosmetics for children were randomly purchased from the local market in Beijing and analyzed by the proposed HPLC method. The detection rate of methylparaben was the highest and the next was propylparaben. Among the 105 samples, two or more kinds of parabens were detected in 72 samples with concentrations ranging from 0.02% to 0.75%; 18 samples contained one kind of paraben with concentrations ranging from 0.002% to 0.06%. In this study, the contents of parabens in the 105 samples were all below the restricted levels. PMID:23449132

  18. Characterization of land subsidence induced by groundwater withdrawals in the plain of Beijing city, China

    NASA Astrophysics Data System (ADS)

    Zhang, Youquan; Gong, Huili; Gu, Zhaoqin; Wang, Rong; Li, Xiaojuan; Zhao, Wenji

    2014-03-01

    The plain of Beijing city in China suffers severe land subsidence owing to groundwater overdraft. The maximum subsidence rate could reach 6 cm/year through the 2000s. An integrated subsidence-monitoring program was designed, including levelling survey, borehole extensometers and multilayer monitoring of groundwater level, with the aim to understand both hydrological and mechanical processes and to characterize the land subsidence. From multilayer compaction monitoring, the major compression layers were identified. The major strata contributing to compression deformation are the second (64.5-82.3 m) and third (102-117 m) aquitards, which contributed around 39 % of the total subsidence. Meanwhile, irrecoverable deformations were also observed in the second (82.3-102 m) and third (117-148 m) confined aquifers; they exhibit elasto-plastic mechanical behavior, which is attributed to the thin beds of silt or silty clay. Stress-strain analysis and oedometer tests were conducted to study the aquifer-system response to pumping and to estimate the specific storage of the major hydrogeologic units. The results reveal the creep behavior and elasto-plastic, visco-elasto-plastic mechanical behavior of the aquitards at different depths. The compressibility of the aquitards in the inelastic range is about one order of magnitude larger than for the elastic range.

  19. Accessibility of Catering Service Venues and Adolescent Drinking in Beijing, China

    PubMed Central

    Lu, Shijun; Du, Songming; Ren, Zhoupeng; Zhao, Jing; Chambers, Christina; Wang, Jinfeng; Ma, Guansheng

    2015-01-01

    This study assessed the association between accessibility of catering service venues and adolescents’ alcohol use over the previous 30 days. The data were collected from cross-sectional surveys conducted in 2014, 2223 students at 27 high schools in Chaoyang and Xicheng districts, Beijing using self-administered questionnaires to collect the adolescents information on socio-demographic characteristics and recent alcohol experiences. The accessibility of, and proximity to, catering service venues were summarized by weights, which were calculated by multiplication of the type-weight and the distance-weight. All sampled schools were categorized into three subgroups (low, middle, and high geographic density) based on the tertile of nearby catering service venues, and a multi-level logistic regression analysis was performed to explore variance between the school levels. Considering the setting characteristics, the catering service venues weighted value was found to account for 8.6% of the school level variance of adolescent alcohol use. The odds ratios (OR) and 95% confidence intervals (CI) of drinking over the past 30-days among adolescents with medium and high accessibility of catering service venues were 1.17 (0.86, 1.57) and 1.47 (1.06, 2.02), respectively (p < 0.001 for trend test). This study addressed a gap in the adolescent drinking influence by the catering service venues around schools in China. Results suggest that the greater accessibility of catering service venues around schools is associated with a growing risk of recent drinking. PMID:26132475

  20. Occurrence and fate of volatile siloxanes in a municipal wastewater treatment plant of Beijing, China.

    PubMed

    Xu, Lin; Shi, Yali; Cai, Yaqi

    2013-02-01

    The occurrence and fate of four cyclic and two linear volatile siloxanes were studied in a municipal Wastewater Treatment Plant (WWTP), Beijing City, China. Aqueous and sludge samples were analyzed by solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS). In the studied WWTP, four cyclic analogs (D3-D6) had significantly higher concentrations and frequencies than the two linear analogs [Octamethyltrisiloxane (L3) and Decamethyltetrasiloxane (L4)], with inputs into the WWTP ranging from 78.2 to 387.7 kg/year. Removal efficiencies of volatile cyclic siloxanes in two parallel secondary treatment processes ranged from 59.3 to 92.7%. For volatile cyclic siloxanes, relative fractions of mass loss by adsorption to sludge ranged from 8.3 to 53.0%, and their adsorption capacities were significantly affected by the dissolved organic matter. Besides adsorption, they were eliminated mainly in anaerobic units (44.4-84.3%). Through in vitro biodegradation experiments, we concluded that in the anaerobic compartments, Hexamethylcyclotrisiloxane (D3) and Dodecamethylcyclohexasiloxane (D6) were eliminated mostly by volatilization, while Octamethylcyclotetrasiloxane (D4) and Decamethylcyclopentasiloxane (D5) may be eliminated by both volatilization and degradation. Furthermore, microbe catalysis hydrolysis was identified as one of the main degradation pathways for D4 and D5 in anaerobic compartments. PMID:23182664

  1. Seismic Hazard and Risk Assessments for Beijing-Tianjin-Tangshan, China, Area

    USGS Publications Warehouse

    Xie, F.; Wang, Z.; Liu, J.

    2011-01-01

    Seismic hazard and risk in the Beijing-Tianjin-Tangshan, China, area were estimated from 500-year intensity observations. First, we digitized the intensity observations (maps) using ArcGIS with a cell size of 0.1 ?? 0.1??. Second, we performed a statistical analysis on the digitized intensity data, determined an average b value (0.39), and derived the intensity-frequency relationship (hazard curve) for each cell. Finally, based on a Poisson model for earthquake occurrence, we calculated seismic risk in terms of a probability of I ??? 7, 8, or 9 in 50 years. We also calculated the corresponding 10 percent probability of exceedance of these intensities in 50 years. The advantages of assessing seismic hazard and risk from intensity records are that (1) fewer assumptions (i. e., earthquake source and ground motion attenuation) are made, and (2) site-effect is included. Our study shows that the area has high seismic hazard and risk. Our study also suggests that current design peak ground acceleration or intensity for the area may not be adequate. ?? 2010 Birkh??user / Springer Basel AG.

  2. Occurrence and distribution of antibiotics in urban soil in Beijing and Shanghai, China.

    PubMed

    Gao, Lihong; Shi, Yali; Li, Wenhui; Liu, Jiemin; Cai, Yaqi

    2015-08-01

    The recycling of reclaimed wastewater for irrigation and road cleaning is an important strategy to minimize water scarcity in megacities. However, little is known regarding the potential accumulation of antibiotics contained in reclaimed wastewater in urban soil. We investigated the occurrence and distribution of eight quinolones (QNs), nine sulfonamides (SAs), and five macrolides (MLs) antibiotics in urban surface soil in Beijing and Shanghai, China. QNs, especially norfloxacin (NOR), ofloxacin (OFL), and ciprofloxacin (CIP) were the predominant antibiotics in urban surface soil, and NOR revealed the highest average concentration of 94.6 μg kg(-1). The antibiotic concentrations in urban soil in our study were higher than those detected in agricultural soils after long-term wastewater irrigation and manure fertilization. The concentrations of antibiotics in Shanghai urban soil showed a significant negative correlation with soil pH and a positive correlation with total organic carbon (TOC), reflecting the effect of speciation and soil organic matter content on sorption and retention. In addition, antibiotic concentrations in the urban soil were positively correlated with heavy metal contents, likely due to their coexistence in reclaimed wastewater and the promoting effect of metals on the sorption of antibiotics. In several soil samples, NOR, OFL, CIP, enrofloxacin (ENR), and fleroxacin (FLE) showed higher concentrations than the trigger value of 100 μg kg(-1) in soil, indicating a potential risk for the environment. PMID:25804657

  3. Carbon Storages in Plantation Ecosystems in Sand Source Areas of North Beijing, China

    PubMed Central

    Liu, Xiuping; Zhang, Wanjun; Cao, Jiansheng; Shen, Huitao; Zeng, Xinhua; Yu, Zhiqiang; Zhao, Xin

    2013-01-01

    Afforestation is a mitigation option to reduce the increased atmospheric carbon dioxide levels as well as the predicted high possibility of climate change. In this paper, vegetation survey data, statistical database, National Forest Resource Inventory database, and allometric equations were used to estimate carbon density (carbon mass per hectare) and carbon storage, and identify the size and spatial distribution of forest carbon sinks in plantation ecosystems in sand source areas of north Beijing, China. From 2001 to the end of 2010, the forest areas increased more than 2.3 million ha, and total carbon storage in forest ecosystems was 173.02 Tg C, of which 82.80 percent was contained in soil in the top 0–100 cm layer. Younger forests have a large potential for enhancing carbon sequestration in terrestrial ecosystems than older ones. Regarding future afforestation efforts, it will be more effective to increase forest area and vegetation carbon density through selection of appropriate tree species and stand structure according to local climate and soil conditions, and application of proper forest management including land-shaping, artificial tending and fencing plantations. It would be also important to protect the organic carbon in surface soils during forest management. PMID:24349223

  4. Newly isolated but uncultivated magnetotactic bacterium of the phylum Nitrospirae from Beijing, China.

    PubMed

    Lin, Wei; Li, Jinhua; Pan, Yongxin

    2012-02-01

    Magnetotactic bacteria (MTB) in the phylum Nitrospirae synthesize up to hundreds of intracellular bullet-shaped magnetite magnetosomes. In the present study, a watermelon-shaped magnetotactic bacterium (designated MWB-1) from Lake Beihai in Beijing, China, was characterized. This uncultivated microbe was identified as a member of the phylum Nitrospirae and represents a novel phylogenetic lineage with ≥6% 16S rRNA gene sequence divergence from all currently described MTB. MWB-1 contained 200 to 300 intracellular bullet-shaped magnetite magnetosomes and showed a helical swimming trajectory under homogeneous magnetic fields; its magnetotactic velocity decreased with increasing field strength, and vice versa. A robust phylogenetic framework for MWB-1 and all currently known MTB in the phylum Nitrospirae was constructed utilizing maximum-likelihood and Bayesian algorithms, which yielded strong evidence that the Nitrospirae MTB could be divided into four well-supported groups. Considering its population densities in sediment and its high numbers of magnetosomes, MWB-1 was estimated to account for more than 10% of the natural remanent magnetization of the surface sediment. Taken together, the results of this study suggest that MTB in the phylum Nitrospirae are more diverse than previously realized and can make important contributions to the sedimentary magnetization in particular environments. PMID:22113917

  5. Newly Isolated but Uncultivated Magnetotactic Bacterium of the Phylum Nitrospirae from Beijing, China

    PubMed Central

    Li, Jinhua; Pan, Yongxin

    2012-01-01

    Magnetotactic bacteria (MTB) in the phylum Nitrospirae synthesize up to hundreds of intracellular bullet-shaped magnetite magnetosomes. In the present study, a watermelon-shaped magnetotactic bacterium (designated MWB-1) from Lake Beihai in Beijing, China, was characterized. This uncultivated microbe was identified as a member of the phylum Nitrospirae and represents a novel phylogenetic lineage with ≥6% 16S rRNA gene sequence divergence from all currently described MTB. MWB-1 contained 200 to 300 intracellular bullet-shaped magnetite magnetosomes and showed a helical swimming trajectory under homogeneous magnetic fields; its magnetotactic velocity decreased with increasing field strength, and vice versa. A robust phylogenetic framework for MWB-1 and all currently known MTB in the phylum Nitrospirae was constructed utilizing maximum-likelihood and Bayesian algorithms, which yielded strong evidence that the Nitrospirae MTB could be divided into four well-supported groups. Considering its population densities in sediment and its high numbers of magnetosomes, MWB-1 was estimated to account for more than 10% of the natural remanent magnetization of the surface sediment. Taken together, the results of this study suggest that MTB in the phylum Nitrospirae are more diverse than previously realized and can make important contributions to the sedimentary magnetization in particular environments. PMID:22113917

  6. Accessibility of Catering Service Venues and Adolescent Drinking in Beijing, China.

    PubMed

    Lu, Shijun; Du, Songming; Ren, Zhoupeng; Zhao, Jing; Chambers, Christina; Wang, Jinfeng; Ma, Guansheng

    2015-07-01

    This study assessed the association between accessibility of catering service venues and adolescents' alcohol use over the previous 30 days. The data were collected from cross-sectional surveys conducted in 2014, 2223 students at 27 high schools in Chaoyang and Xicheng districts, Beijing using self-administered questionnaires to collect the adolescents information on socio-demographic characteristics and recent alcohol experiences. The accessibility of, and proximity to, catering service venues were summarized by weights, which were calculated by multiplication of the type-weight and the distance-weight. All sampled schools were categorized into three subgroups (low, middle, and high geographic density) based on the tertile of nearby catering service venues, and a multi-level logistic regression analysis was performed to explore variance between the school levels. Considering the setting characteristics, the catering service venues weighted value was found to account for 8.6% of the school level variance of adolescent alcohol use. The odds ratios (OR) and 95% confidence intervals (CI) of drinking over the past 30-days among adolescents with medium and high accessibility of catering service venues were 1.17 (0.86, 1.57) and 1.47 (1.06, 2.02), respectively (p < 0.001 for trend test). This study addressed a gap in the adolescent drinking influence by the catering service venues around schools in China. Results suggest that the greater accessibility of catering service venues around schools is associated with a growing risk of recent drinking. PMID:26132475

  7. Methane Emissions from Natural Gas Vehicles in Beijing, Baoding, and Shijiazhuang, China during CAREBEIJING Field Campaign

    NASA Astrophysics Data System (ADS)

    Pan, D.; Tao, L.; Sun, K.; Golston, L.; Zhang, Y.; Zhu, T.; Zondlo, M. A.

    2014-12-01

    From 2002-2012, number of Natural Gas Vehicles (NGVs) increased from 36,000 to 1.6 million (44 times) and is projected to reach 4.0 million by 2020. Deploying NGVs is an effective way to relieve Chinese air pollution, since NGVs can reduce emissions of particulate matter (PM) and NOx by 91% and 59% compared to gasoline vehicles (GVs). However, previous studies in US showed that NGVs might emit more methane (CH4) than GVs, which is an important greenhouse gas and a precursor to air pollution. Despite the tremendous growth of NGVs and importance of CH4, CH4 emissions from NGVs in China haven't been carefully studied yet. During CAREBEIJING field campaign in 2013 and 2014, we used a mobile platform to conduct on-road measurement of CH4, carbon monoxide (CO), carbon dioxide (CO2), and NH3 (ammonia) in Beijing, Baoding, and Shijiazhuang, China. We found that the mean on-road CH4:CO2 ratio from NGVs is (0.004±0.0003) g CH4/g CO2, which is 20 times higher than previous report on CH4:CO2 emission ratio from US cars. Although NGVs can reduce 25% CO2 compared to GVs, CH4 emitted from NGVs would diminish this number to 19%. Using this emission ratio, we estimate that NGVs in China emitted 37 Gg CH4 in 2010. CH4 emissions from NGVs would increase to 207 Gg in 2020 (by a factor of 560%) if no regulation of CH4 emissions from NGVs were implemented. Most of these emissions occur in urban areas, requiring analyses of their impacts on air quality in such regions. Therefore, a mass balance model is used to study the proportion of CH4 emissions from NGVs in total urban CH4 emissions for Baoding city. Finally, in order to better inform policy decisions, a life-cycle analysis is made to estimate potential CH4 emissions from NGV related industrials. Overall, NGVs are promising alternative fuel vehicles in China, but more attention should be paid to quantify their CH4 emissions.

  8. Elimination of polar micropollutants and anthropogenic markers by wastewater treatment in Beijing, China.

    PubMed

    Qi, Weixiao; Singer, Heinz; Berg, Michael; Müller, Beat; Pernet-Coudrier, Benoit; Liu, Huijuan; Qu, Jiuhui

    2015-01-01

    Anthropogenic contamination of surface waters in Asia is on the increase. While polar organic contaminants are gradually recognized for their impacts on aquatic ecosystems in the Western World, less is known about the situation in Asia. In developing countries like China, water resources are particularly vulnerable. We investigated the occurrence, elimination, and per capita loads of a wide range of pharmaceuticals, household chemicals and pesticides in five Beijing WWTPs representative for megacities in China, and compare the efficiency of different treatment processes. Based on initial screening for 268 micropollutants using high-resolution mass spectrometry, 33 compounds were examined in detail. Pollutant concentrations in raw wastewater ranged from <0.02 μg L(-1) for pesticides to >20 μg L(-1) for caffeine and the contrast agent iopromide. Concentrations in the WWTP effluents were generally <1 μg L(-1), except for some pharmaceuticals, iopromide (1.2-18 μg L(-1)), caffeine (0.025-2.3 μg L(-1)), and the artificial sweetener sucralose (2.7-3.5 μg L(-1)). Elimination efficiencies varied greatly from <1% to close to 100%, with macrolides, some sulfonamides, metronidazole, iopromide, and 4-acetamidoantipyrine being the most persistent compounds. Total per capita loads of the investigated micropollutants were lower than in communal wastewater of Europe, amounting to 7.9-12.2 and 2.0-6.5 g d(-1)1000 inhabitants(-1) in the influents and effluents, respectively, with an average release of ∼100 kg d(-1) by the 11.4 million people and 2.3 million m(3) of wastewater treated per day. Since the wastewater effluents are often used for agricultural irrigation, residual organic pollutants pose a threat to food safety, the development of antibacterial resistance, and combined effects of micropollutants in the aquatic environment. PMID:25305554

  9. Characterization of the chemical composition of PM2.5 emitted from on-road China III and China IV diesel trucks in Beijing, China.

    PubMed

    Wu, Bobo; Shen, Xianbao; Cao, Xinyue; Yao, Zhiliang; Wu, Yunong

    2016-05-01

    The composition of diesel exhaust fine particulate matter (PM2.5) is of growing interest because of its impacts on health and climatic factors and its application in source apportionment and aerosol modeling. We characterized the detailed chemical composition of the PM2.5, including the organic carbon (OC), elemental carbon (EC), water-soluble ions (WSIs), and elemental contents, emitted from China III and China IV diesel trucks (nine each) based on real-world measurements in Beijing using a portable emissions measurement system (PEMS). Carbonaceous compounds were the dominant components (totaling approximately 87%) of the PM2.5, similar to the results (greater than 80% of the PM2.5) of our previous study of on-road China III diesel trucks. In general, the amounts of individual component groups (carbonaceous compounds, WSIs, and elements) and PM2.5 emissions for China IV diesel trucks were lower than those of China III diesel trucks of the same size, except for the WSIs and elements for the light- and medium-duty diesel trucks. The EC/OC mass ratios were strongly dependent on the emission standards, and the ratios of China IV diesel trucks were higher than those of China III diesel trucks of the same size. The chemical species in the PM2.5 were significantly affected by the driving conditions. Overall, the emission factors (EFs) of the PM2.5 and OC under non-highway (NHW) driving conditions were higher than those under highway (HW) driving conditions, and the EC/OC mass ratios presented an increasing trend, with decreasing OC/PM2.5 and increasing EC/PM2.5 from NHW to HW driving conditions; similar trends were reported in our previous study. In addition, Pearson's correlation coefficients among the PM2.5 species were analyzed to determine the relationships among the various chemical components. PMID:26897401

  10. Sources and Processes Affecting Fine Particulate Matter Pollution over North China: An Adjoint Analysis of the Beijing APEC Period.

    PubMed

    Zhang, Lin; Shao, Jingyuan; Lu, Xiao; Zhao, Yuanhong; Hu, Yongyun; Henze, Daven K; Liao, Hong; Gong, Sunling; Zhang, Qiang

    2016-08-16

    The stringent emission controls during the APEC 2014 (the Asia-Pacific Economic Cooperation Summit; November 5-11, 2014) offer a unique opportunity to quantify factors affecting fine particulate matter (PM2.5) pollution over North China. Here we apply a four-dimensional variational data assimilation system using the adjoint model of GEOS-Chem to address this issue. Hourly surface measurements of PM2.5 and SO2 for October 15-November 14, 2014 are assimilated into the model to optimize daily aerosol primary and precursor emissions over North China. Measured PM2.5 concentrations in Beijing average 50.3 μg m(-3) during APEC, 43% lower than the mean concentration (88.2 μg m(-3)) for the whole period including APEC. Model results attribute about half of the reduction to meteorology due to active cold surge occurrences during APEC. Assimilation of surface measurements largely reduces the model biases and estimates 6%-30% lower aerosol emissions in the Beijing-Tianjin-Hebei region during APEC than in late October. We further demonstrate that high PM2.5 events in Beijing during this period can be occasionally contributed by natural mineral dust, but more events show large sensitivities to inorganic aerosol sources, particularly emissions of ammonia (NH3) and nitrogen oxides (NOx) reflecting strong formation of aerosol nitrate in the fall season. PMID:27434821

  11. Comparative studies on the concentration of rare earth elements and heavy metals in the atmospheric particulate matter in Beijing, China, and in Delft, The Netherlands.

    PubMed

    Wang, C X; Zhu, W; Peng, A; Guichreit, R

    2001-05-01

    Atmospheric particulate matter (APM) was collected at three sampling sites in Beijing, China, from February to June 1998. The concentrations of rare earth elements (REE) and cobalt (Co), zinc (Zn), copper (Cu), cadmium (Cd) and lead (Pb) in the APM were determined by inductively coupled plasma mass spectrometry (ICP-MS). The results obtained in Beijing, China, were compared to that obtained in Delft, the Netherlands, in 1997. The influence of coal combustion was considered. The results demonstrated that the content of APM, the concentrations of REE and Co, Zn, Cd, Pb in the APM in Beijing, China, were higher than that in Delft, the Netherlands. From the ratios of La to Ce, and La to Sm, which may be used as tracers for the origin of the REE, it is concluded that the origins of REE in China differ from those in the Netherlands. PMID:11392744

  12. Occurrence of mycotoxins in feed ingredients and complete feeds obtained from the Beijing region of China

    PubMed Central

    2014-01-01

    Background The current study was carried out to provide a reference for the control of mycotoxin contamination in feed ingredients and complete feeds for swine. Methods A total of 55 feed ingredients, including 14 corn, 13 wheat bran, 11 soybean meal and 17 dried distillers grains with solubles (DDGS) as well as 76 complete swine feeds including 7 creep feeds, 14 starter feeds, 14 grower feeds, 18 grower-finisher feeds, 10 gestating sow feeds, and 13 lactating sow feeds were randomly collected from 15 swine farms located in the Beijing region of China from July to August 2011. Immunoaffinity clean-up, using High-Performance Liquid Chromatography (HPLC) in combination with UV or Fluorescence Detection, was used for quantitative analysis of aflatoxin B1 (AFB1), deoxynivalenol (DON), zearalenone (ZEA) and ochratoxin A (OTA) in the ingredients and complete feeds. Results DON and ZEA were the most prevalent mycotoxins found. DON was detected at percentages of 93, 92, 54, 100 and 97% with a mean level of 1.01, 0.44, 0.05, 1.36 and 0.65 ppm in the samples of corn, wheat bran, soybean meal, DDGS and complete feeds, respectively. The detected percentages of ZEA were 100, 100, 54, 100 and 100 with mean levels of 109.1, 14.9, 9.2, 882.7 and 58.9 ppb in the same samples. In the wheat bran and soybean meal samples, the content of all four mycotoxins were below the maximum limits set by Chinese regulations while the percentage of samples that exceeded regulatory limits were 7, 57 and 7% for corn, and 7, 14 and 3% for the complete feeds for AFB1, DON and OTA respectively. DDGS showed the most serious mycotoxin contamination and the percentage of samples that exceeded regulatory limits were 6, 88 and 41%, for AFB1, DON and ZEA, respectively. Conclusions This paper is the first to present data on the natural occurrence of AFB1, DON, ZEA and OTA in ingredients and complete feeds obtained from swine farms in China’s Beijing region. The data shows that feed ingredients and

  13. Effects of meteorology and secondary particle formation on visibility during heavy haze events in Beijing, China.

    PubMed

    Zhang, Qiang; Quan, Jiannong; Tie, Xuexi; Li, Xia; Liu, Quan; Gao, Yang; Zhao, Delong

    2015-01-01

    The causes of haze formation in Beijing, China were analyzed based on a comprehensive measurement, including PBL (planetary boundary layer), aerosol composition and concentrations, and several important meteorological parameters such as visibility, RH (relative humidity), and wind speed/direction. The measurement was conducted in an urban location from Nov. 16, 2012 to Jan. 15, 2013. During the period, the visibility varied from >20 km to less than a kilometer, with a minimum visibility of 667 m, causing 16 haze occurrences. During the haze occurrences, the wind speeds were less than 1m/s, and the concentrations of PM2.5 (particle matter with radius less than 2.5 μm) were often exceeded 200 μg/m(3). The correlation between PM2.5 concentration and visibility under different RH values shows that visibility was exponentially decreased with the increase of PM2.5 concentrations when RH was less than 80%. However, when RH was higher than 80%, the relationship was no longer to follow the exponentially decreasing trend, and the visibility maintained in very low values, even with low PM2.5 concentrations. Under this condition, the hygroscopic growth of particles played important roles, and a large amount of water vapor acted as particle matter (PM) for the reduction of visibility. The variations of meteorological parameters (RH, PBL heights, and WS (wind speed)), chemical species in gas-phase (CO, O3, SO2, and NOx), and gas-phase to particle-phase conversions under different visibility ranges were analyzed. The results show that from high visibility (>20 km) to low visibility (<2 km), the averaged PBL decreased from 1.24 km to 0.53 km; wind speeds reduced from 1m/s to 0.5m/s; and CO increased from 0.5 ppmv to 4.0 ppmv, suggesting that weaker transport/diffusion caused the haze occurrences. This study also found that the formation of SPM (secondary particle matter) was accelerated in the haze events. The conversions between SO2 and SO4 as well as NOx to NO3(-) increased

  14. Occurrence and distribution of antibiotics, antibiotic resistance genes in the urban rivers in Beijing, China.

    PubMed

    Xu, Yan; Guo, Changsheng; Luo, Yi; Lv, Jiapei; Zhang, Yuan; Lin, Haixia; Wang, Li; Xu, Jian

    2016-06-01

    The occurrence and distribution of sulfonamide and tetracycline, corresponding bacterial resistant rate and resistance genes (ARGs) and two integrase genes were investigated in seven urban rivers in Beijing, China. The total concentration of sulfonamide and tetracycline ranged from 1.3 × 10(1)-1.5 × 10(3) ng/L and 3.9 × 10(1)-5.4 × 10(4) ng/L for water, and 1.0 × 10(0)-2.7 × 10(2) and 3.1 × 10(1)-1.6 × 10(2) ng/g for sediment, respectively. The sul resistant rate was 2-3 times higher than tet resistant rate in both surface water and sediment. The average rate of sul resistance and tet resistance were up to 81.3% and 38.6% in surface water, 89.1% and 69.4% in the sediment, respectively. The sul1, tetA and tetE genes were predominant in term of the absolute abundance. The absolute abundance of ARGs in Wenyu River and Qinghe River, which were close to the direct discharging sites, were 5-50 times higher than those in the other investigated urban rivers, suggesting that the source release played an important role in the distribution of ARGs. The sul1 and sul2 genes had positive correlation (p < 0.05) with sulfonamides, and the tet resistance genes was significantly correlated with tetracyclines (p < 0.05), indicating that some ARGs and antibiotics in the urban rivers had identical sources of pollution. Considering principal component analysis, sampling sites (QH5, QH6, B1, B2, B3 and BX2) intimated that a complex interplay of processes govern fate and transport of ARGs in the junction of rivers. These results are significant to understand the fate, and the contribution of ARGs from the source release. In view of the large-scale investigation of urban rivers system in Beijing, it reflected the bacterial resistance in sewage drainage system. Such investigation highlights the management on controlling the pollutant release which was seemed as a major driving force for the maintenance and propagation of many ARGs during the development of

  15. Survey Study on Chinese University Students' Perceptions of the Political Systems of China and the United States: Using as Examples Five Key Universities in Beijing, Including Peking (Beijing) University and Tsinghua (Qinghua) University

    ERIC Educational Resources Information Center

    Shengluo, Chen

    2011-01-01

    Through surveys of students at Beijing University, Qinghua University, and other institutions, this article finds that today, twenty years after the political disturbance in 1989 and despite the long-term and unremitting efforts made by the Chinese government, China's college students still take a better view of the U.S. political system than they…

  16. 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…

  17. New Quaternary magnetostratigraphic results from Beijing, China, and their urban geological implications

    NASA Astrophysics Data System (ADS)

    Yuan, H.; Cai, X.; Yang, T.; Wu, H.; Li, H.; Zhang, L.; Zhang, S.

    2012-12-01

    A new magnetostratigraphic investigation has been carried out on the terrestrial sedimentary sequences from three boreholes ZK11-2, ZK12-1 and ZK12-2, which were drilled from the alluvial-proluvial fan of Chaobai River, Beijing, China. Seismic data showed that two parallel normal faults may lie beneath. But good dating data are still unavailable to constrain the activity time of both faults till now. So the magnetostratigraphic data were achieved in this study. ZK11-2 and ZK12-1 cores are both 299 m long and ZK12-2 core is 719 m long. Paleomagnetic samples were collected at a 1 m interval for ZK11-2 and ZK12-1 cores and a 0.5 m interval for ZK12-2 core. The samples were cut to cubic specimens by a stainless saw and then were worn to 8 cm3 cube using sandpapers. The K-T curves indicate that the main magnetic grains of the three cores are magnetite. Stepwise thermal demagnetization on 885 specimens was finished using ASC TD-48 furnace in 40-100°C steps up to 580°C. All remanence measurements were finished on the 2G 755-4K superconducting magnetometer in Paleomagnetism and Environmental Magnetism Laboratory, China University of Geosciences (Beijing). All the instruments are placed in the magnetic shield room with a low magnetic field less than ~300 nT. In the vector component diagrams, a low-stability component exists between NRM to 100°C in many samples, which may be the viscous remanence overprinted by the present geomagnetic field. Most specimens could isolate a stable component that decayed toward the origin after being heated above 400°C. This is considered as the characteristic remanent magnetization (ChRM). Based on the results of the ChRM, the Brunhes/Matsuyama (B/M) and Matsuyama/Guass (M/G) boundaries, the Jaramillo subchron and the boundaries of the Olduvai subchron were determined. The B/M boundary is at the depth of 93 m for ZK11-2 core, 118 m for ZK12-1 core and 170 m for ZK12-2 core. The M/G boundary is at the depth of 232 m for ZK12-1 core and 710

  18. Multilevel Modelling with Spatial Interaction Effects with Application to an Emerging Land Market in Beijing, China

    PubMed Central

    Dong, Guanpeng; Harris, Richard; Jones, Kelvyn; Yu, Jianhui

    2015-01-01

    This paper develops a methodology for extending multilevel modelling to incorporate spatial interaction effects. The motivation is that classic multilevel models are not specifically spatial. Lower level units may be nested into higher level ones based on a geographical hierarchy (or a membership structure—for example, census zones into regions) but the actual locations of the units and the distances between them are not directly considered: what matters is the groupings but not how close together any two units are within those groupings. As a consequence, spatial interaction effects are neither modelled nor measured, confounding group effects (understood as some sort of contextual effect that acts ‘top down’ upon members of a group) with proximity effects (some sort of joint dependency that emerges between neighbours). To deal with this, we incorporate spatial simultaneous autoregressive processes into both the outcome variable and the higher level residuals. To assess the performance of the proposed method and the classic multilevel model, a series of Monte Carlo simulations are conducted. The results show that the proposed method performs well in retrieving the true model parameters whereas the classic multilevel model provides biased and inefficient parameter estimation in the presence of spatial interactions. An important implication of the study is to be cautious of an apparent neighbourhood effect in terms of both its magnitude and statistical significance if spatial interaction effects at a lower level are suspected. Applying the new approach to a two-level land price data set for Beijing, China, we find significant spatial interactions at both the land parcel and district levels. PMID:26086913

  19. Impact of anthropogenic aerosols on regional climate change in Beijing, China

    NASA Astrophysics Data System (ADS)

    Zhao, B.; Liou, K. N.; He, C.; Lee, W. L.; Gu, Y.; Li, Q.; Leung, L. R.

    2015-12-01

    Anthropogenic aerosols affect regional climate significantly through radiative (direct and semi-direct) and indirect effects, but the magnitude of these effects over megacities are subject to large uncertainty. In this study, we evaluated the effects of anthropogenic aerosols on regional climate change in Beijing, China using the online-coupled Weather Research and Forecasting/Chemistry Model (WRF/Chem) with the Fu-Liou-Gu radiation scheme and a spatial resolution of 4km. We further updated this radiation scheme with a geometric-optics surface-wave (GOS) approach for the computation of light absorption and scattering by black carbon (BC) particles in which aggregation shape and internal mixing properties are accounted for. In addition, we incorporated in WRF/Chem a 3D radiative transfer parameterization in conjunction with high-resolution digital data for city buildings and landscape to improve the simulation of boundary-layer, surface solar fluxes and associated sensible/latent heat fluxes. Preliminary simulated meteorological parameters, fine particles (PM2.5) and their chemical components agree well with observational data in terms of both magnitude and spatio-temporal variations. The effects of anthropogenic aerosols, including BC, on radiative forcing, surface temperature, wind speed, humidity, cloud water path, and precipitation are quantified on the basis of simulation results. With several preliminary sensitivity runs, we found that meteorological parameters and aerosol radiative effects simulated with the incorporation of improved BC absorption and 3-D radiation parameterizations deviate substantially from simulation results using the conventional homogeneous/core-shell configuration for BC and the plane-parallel model for radiative transfer. Understanding of the aerosol effects on regional climate change over megacities must consider the complex shape and mixing state of aerosol aggregates and 3D radiative transfer effects over city landscape.

  20. Occurrence of antibiotics in eight sewage treatment plants in Beijing, China.

    PubMed

    Gao, Lihong; Shi, Yali; Li, Wenhui; Niu, Hongyun; Liu, Jiemin; Cai, Yaqi

    2012-02-01

    The occurrence, removal efficiency and seasonal variation of 22 antibiotics, including eight fluoroquinolones, nine sulfonamides and five macrolides, were investigated in eight sewage treatment plants (STPs) in Beijing, China. A total of 14 antibiotics were detected in wastewater samples, with the maximum concentration being 3.1 μg L(-1) in the influent samples and 1.2 μg L(-1) in the effluent samples. The most frequently detected antibiotics were ofloxacin, norfloxacin, sulfadiazine, sulfamethoxazole, erythromycin and roxithromycin; of these, the concentration of ofloxacin was the highest in most of the influent and effluent samples. Eighteen antibiotics were detected in the sludge samples, with concentrations ranging from 1.0×10(-1) to 2.1×10(4) μg kg(-1). The dominant antibiotics found in the sludge samples were the fluoroquinolones, with ofloxacin having the highest concentration in all the sludge samples. The antibiotics could not be removed completely by the STPs, and the mean removal efficiency ranged from -34 to 72%. Of all the antibiotics, the fluoroquinolones were removed comparatively more efficiently, probably due to their adsorption to sludge. Seasonal variation of the antibiotics in the sludge samples was also studied. The concentrations of antibiotics in winter were higher than in spring and autumn. Since the total levels of the fluoroquinolones detected in the influent samples were lower than the predicted no-effect concentration (PNEC) of 8.0 μg L(-1), the residues of these antibiotics would be unlikely to have adverse effects on microorganisms involved in sewage treatment processes. PMID:22154158

  1. Historic and future trends of vehicle emissions in Beijing, 1998-2020: A policy assessment for the most stringent vehicle emission control program in China

    NASA Astrophysics Data System (ADS)

    Zhang, Shaojun; Wu, Ye; Wu, Xiaomeng; Li, Mengliang; Ge, Yunshan; Liang, Bin; Xu, Yueyun; Zhou, Yu; Liu, Huan; Fu, Lixin; Hao, Jiming

    2014-06-01

    As a pioneer in controlling vehicle emissions within China, Beijing released the Clean Air Action Plan 2013-2017 document in August 2013 to improve its urban air quality. It has put forward this plan containing the most stringent emission control policies and strategies to be adopted for on-road vehicles of Beijing. This paper estimates the historic and future trends and uncertainties in vehicle emissions of Beijing from 1998 to 2020 by applying a new emission factor model for the Beijing vehicle fleet (EMBEV). Our updated results show that total emissions of CO, THC, NOx and PM2.5 from the Beijing vehicle fleet are 507 (395-819) kt, 59.1 (41.2-90.5) kt, 74.7 (54.9-103.9) kt and 2.69 (1.91-4.17) kt, respectively, at a 95% confidence level. This represents significant reductions of 58%, 59%, 31% and 62%, respectively, relative to the total vehicle emissions in 1998. The past trends clearly posed a challenge to NOx emission mitigation for the Beijing vehicle fleet, especially in light of those increasing NOx emissions from heavy-duty diesel vehicles (HDDVs) which have partly offset the reduction benefit from light-duty gasoline vehicles (LDGVs). Because of recently announced vehicle emission controls to be adopted in Beijing, including tighter emissions standards, limitations on vehicle growth by more stringent license control, promotion of alternative fuel technologies (e.g., natural gas) and the scrappage of older vehicles, estimated vehicle emissions in Beijing will continue to be mitigated by 74% of CO, 68% of THC, 56% of NOx and 72% of PM2.5 in 2020 compared to 2010 levels. Considering that many of the megacities in China are facing tremendous pressures to mitigate emissions from on-road vehicles, our assessment will provide a timely case study of significance for policy-makers in China.

  2. Prevalence of Antibodies against Neospora caninum in Père David's Deer ( Elaphurus davidianus ) in Beijing, China.

    PubMed

    Han, Fangjie; Fu, Yong; Zhang, Changsheng; Liu, Qun; Xu, Jianhai; Liu, Jing

    2016-04-28

    Neospora caninum is an apicomplexan protozoan and causes neuromuscular disorders in canids and abortions in cattle worldwide. We screened sera samples from 49 free-ranging Père David's deer ( Elaphurus davidianus ) in a nature reserve in Beijing, China, for antibodies against N. caninum using indirect fluorescence antibody tests and western blot tests. Antibodies were found in 27% of the deer. Western blot analysis revealed antibody reactivity against immunodominant N. caninum antigens of 16, 25, and 37 kDa in size together with other visible bands. PMID:27124330

  3. Pollution characteristics and health risk assessment of heavy metals in street dusts from different functional areas in Beijing, China.

    PubMed

    Wei, Xin; Gao, Bo; Wang, Peng; Zhou, Huaidong; Lu, Jin

    2015-02-01

    Street dusts from Heavy Density Traffic Area, Residential Area, Educational Area and Tourism Area in Beijing, China, were collected to study the distribution, accumulation and health risk assessment of heavy metals. Cr, Cu, Zn, Cd and Pb concentrations were in higher concentrations in these four locations than in the local soil background. In comparison with the concentrations of selected metals in other cities, the concentrations of heavy metals in Beijing were generally at moderate or low levels. Ni, Cu, Zn and Pb concentrations in the Tourism Area were the highest among four different areas in Beijing. A pollution assessment by Geoaccumulation Index showed that the pollution level for the heavy metals is in the following order: Cd>Pb>Zn>Cu>Cr>Ni. The Cd levels can be considered "heavily contaminated" status. The health risk assessment model that was employed to calculate human exposure indicated that both non-carcinogenic and carcinogenic risks of selected metals in street dusts were generally in the low range, except for the carcinogenic risk from Cr for children. PMID:25463870

  4. Numerical analysis to determine the impact of land subsidence on high-speed railway routes in Beijing, China

    NASA Astrophysics Data System (ADS)

    Ye, C.; Yang, Y.; Tian, F.; Luo, Y.; Zhou, Y.

    2015-11-01

    More than 10 high-speed railway routes with top speeds of 300 km h-1 are expected to be operational from Beijing by the year 2020. However, the safety of these routes is affected by the occurrence of land subsidence. This paper focuses on the Beijing-Tianjin Intercity High-Speed Railway (BTR), the first high-speed railway in China, to analyze the operational safety of high-speed railway routes by analyzing both regional land subsidence and local differential subsidence caused by groundwater drawing. The Beijing construction stratum is mainly composed of cohesive soil, and the BTR has a maximum accumulative subsidence of > 800 mm and a maximum subsidence rate of > 80 mm a-1. In this paper, finite-element software ABAQUS is used to analyze groundwater drawdown and land subsidence caused by local water drawing, and its effect on the bearing capacity of railway bridge pile foundations and the orbit concrete supporting course. The analysis provides a technical basis for developing prevention and control engineering measures against land subsidence so as to guarantee the safe operation of these high-speed railway routes.

  5. Characteristics of aerosol optical properties and meteorological parameters during three major dust events (2005-2010) over Beijing, China

    NASA Astrophysics Data System (ADS)

    Cao, Chunxiang; Zheng, Sheng; Singh, Ramesh P.

    2014-12-01

    Multi-satellite sensors are capable of monitoring transport and characteristics of dust storms and changes in atmospheric parameters along their transport. The present paper discusses aerosol optical properties and meteorological parameters during major dust storm events occurred in the period 2005-2010 over Beijing, China. The back trajectory model shows that the dust is transported from the Inner Mongolia and Mongolia arid regions to Beijing. High aerosol optical depth (AOD) at the wavelength 675 nm and low Ångström exponent (AE) values in the wavelength 440-870 nm are observed during dusty days. The aerosol size distribution (ASD) in coarse mode shows a large increase in the volume during dusty days. The single scattering albedo (SSA) increases with higher wavelength on dusty days, and is generally found to be higher compared to the days prior to and after the dust events, indicating the presence of high concentrations of scattering particles due to dust storm events. The physico-chemical properties of aerosols during dusty and non dusty days show distinct characteristics as reflected from the changes in the real and imaginary parts of refractive index (RI). In addition, the CO volume mixing ratio (COVMR) from Atmospheric Infrared Sounder (AIRS) shows a pronounced decrease on dusty days, while the H2O mass mixing ratio (H2OMMR) shows enhanced signal. Furthermore, enhanced level of water vapor (WV) using Moderate Resolution Imaging Spectroradiometer (MODIS) data is also observed in and around Beijing over the dust storms track.

  6. Spatial distribution, temporal variation and risks of parabens and their chlorinated derivatives in urban surface water in Beijing, China.

    PubMed

    Li, Wenhui; Gao, Lihong; Shi, Yali; Wang, Yuan; Liu, Jiemin; Cai, Yaqi

    2016-01-01

    The occurrence and distribution of 13 target compounds, including eight parabens, four chlorinated parabens and p-hydroxybenzoic acid (PHBA), were detected in surface water samples at 35 sampling sites in the Beijing River system, China. The surface water samples were collected from the main rivers and lakes in the urban area monthly from July 2013 to June 2014 (except the frozen period). Laboratory analyses revealed that parabens were ubiquitous in the surface water of Beijing. PHBA was the predominant compound in the surface water samples, with the average concentration of 239ngL(-1), followed by the total amount of chlorinated parabens (average 50.1ng/L) and parabens (average 44.3ng/L). It is noteworthy that octylparaben with longer chain was firstly detected in the surface water. Significant difference was observed for paraben concentrations from different sampling sites, and the highest level of parabens was found in the Xiaotaihou River, which was mainly due to the untreated sewage discharge. Seasonal variation of target compounds in the urban surface water was also studied, and parabens exhibited a different temporal variation from chlorinated derivatives. A combination of factors including high residual chlorine level and water temperature as well as intense ultraviolet radiation might enhance the persistence of chlorinated parabens in chlorinated water during the wet season. Risk assessment showed that parabens and their chlorinated derivatives are not likely to produce biological effects on aquatic ecosystems at current levels in the surface water of Beijing. PMID:26363399

  7. Air quality of Beijing (China) and Delhi (India) and impact on Human Health and Climate in Asia

    NASA Astrophysics Data System (ADS)

    Zheng, S.; Singh, R. P.; Wu, Y.; Wu, C.

    2015-12-01

    Air pollution has been estimated to represent a significant fraction of the total mortality attributable to 26 risk factors assessed by the World Health Organization global burden of disease project. Delhi is distributed over 1484 km2 with population density of 11297/km2 (as in 2011) and surrounded by highly industrialized National Capital region (NCR) with population density of 1050/km2. Beijing covers an area of 16,800 km2, with population density of 1300/km2 (upto 2014). It is located at the foothills of Yan Mountains and Taihang Mountains, in the North China Plain. Both these cities suffer with poor air quality and are severely affected by dense haze, fog and smog during summer and winter seasons. Earlier studies in developing countries have concentrated on limited air quality parameters. Detailed results from trace gases (O3, NO, NO2, and CO) and particulate matter (PM10 and PM2.5) in two Asian megacities, Delhi (India) and Beijing (China), will be presented. Trace gases and particulate matter in Beijing were collected at 31 sites during 2013-2014. The measurements in Delhi were carried out at 8 sites during October 2010 - March 2013. The annual average of PM10, PM2.5, O3, NO, NO2, and CO over Delhi in 2013 is 199 ug/m3, 123 ug/m3, 25.6 ppb, 21.5 ppb, 15.8 ppb, 1.7 ppb, respectively. The annual average of PM10, PM2.5, O3, NO2, CO, and SO2 over Beijing is 113 ug/m3, 85 ug/m3, 51 ug/m3, 46 ug/m3, 1.3 mg/m3, 23 ug/m3, respectively. The annual and seasonal variations of trace gases and particulate matter in Beijing and Delhi are also analyzed, as well as spatial changes of air pollution in these two cities. A comparative analysis in these two cities and the sources of pollution and their impact on human health and Asian climate will be discussed.

  8. Estimation of PM10 in the traffic-related atmosphere for three road types in Beijing and Guangzhou, China.

    PubMed

    Wang, Yu; Li, Jiong; Cheng, Xiang; Lun, Xiaoxiu; Sun, Dezhi; Wang, Xingzu

    2014-01-01

    The levels of roadside PM10 in Beijing, China, were investigated in 2011 and 2012 on a seasonal basis to estimate the population exposure to particulates for three road types. The measurements of PM10 were also conducted in the southern Chinese megacity of Guangzhou for comparison purposes. The results showed that roadside PM10 in Beijing correlated strongly with the PM10 background in the urban atmosphere. The levels of PM10 in street canyons were markedly higher than those along the open roads and in crossroad areas because of limited ventilation. An elevation of PM10 was observed in April, which was possibly due to the sand storms that frequently occur in the spring. Based on these observations, roadside PM10 in Beijing could have multiple origins and was to some extent dispersion-governed. In Guangzhou, the roadside PM10 did not closely relate to the background values. The PM10 pollution was greatly affected by local traffic conditions. The simulation of PM10 for different road types was completed during the study period using the Motor Vehicle Emissions Factor Model (MOBILE6.2) as an emission model and the California Line Source Dispersion Model (CALINE4) and Operational Street Pollution Model (OSPM) as dispersion models. The MOBILE6.2/CALINE4 software package was demonstrated to be sufficient for the simulation of PM10 in the open roads and crossroad areas in both Beijing and Guangzhou, and the simulation results of roadside PM10 in the street canyons by the MOBILE6.2/OSPM package were in close agreement with those of the measurements. PMID:24649707

  9. Genetic basis of high level aminoglycoside resistance in Acinetobacter baumannii from Beijing, China

    PubMed Central

    Nie, Lu; Lv, Yuemeng; Yuan, Min; Hu, Xinxin; Nie, Tongying; Yang, Xinyi; Li, Guoqing; Pang, Jing; Zhang, Jingpu; Li, Congran; Wang, Xiukun; You, Xuefu

    2014-01-01

    The objective of this study was to investigate the genetic basis of high level aminoglycoside resistance in Acinetobacter baumannii clinical isolates from Beijing, China. 173 A. baumannii clinical isolates from hospitals in Beijing from 2006 to 2009 were first subjected to high level aminoglycoside resistance (HLAR, MIC to gentamicin and amikacin>512 µg/mL) phenotype selection by broth microdilution method. The strains were then subjected to genetic basis analysis by PCR detection of the aminoglycoside modifying enzyme genes (aac(3)-I, aac(3)-IIc, aac(6′)-Ib, aac(6′)-II, aph(4)-Ia, aph(3′)-I, aph(3′)-IIb, aph(3′)-IIIa, aph(3′)-VIa, aph(2″)-Ib, aph(2″)-Ic, aph(2″)-Id, ant(2″)-Ia, ant(3″)-I and ant(4′)-Ia) and the 16S rRNA methylase genes (armA, rmtB and rmtC). Correlation analysis between the presence of aminoglycoside resistance gene and HLAR phenotype were performed by SPSS. Totally 102 (58.96%) HLAR isolates were selected. The HLAR rates for year 2006, 2007, 2008 and 2009 were 52.63%, 65.22%, 51.11% and 70.83%, respectively. Five modifying enzyme genes (aac(3)-I, detection rate of 65.69%; aac(6′)-Ib, detection rate of 45.10%; aph(3′)-I, detection rate of 47.06%; aph(3′)-IIb, detection rate of 0.98%; ant(3″)-I, detection rate of 95.10%) and one methylase gene (armA, detection rate of 98.04%) were detected in the 102 A. baumannii with aac(3)-I+aac(6′)-Ib+ant(3″)-I+armA (detection rate of 25.49%), aac(3)-I+aph(3′)-I+ant(3″)-I+armA (detection rate of 21.57%) and ant(3″)-I+armA (detection rate of 12.75%) being the most prevalent gene profiles. The values of chi-square tests showed correlation of armA, ant(3″)-I, aac(3)-I, aph(3′)-I and aac(6′)-Ib with HLAR. armA had significant correlation (contingency coefficient 0.685) and good contingency with HLAR (kappa 0.940). The high rates of HLAR may cause a serious problem for combination therapy of aminoglycoside with β-lactams against A. baumannii infections. As armA was

  10. The Characteristic of Heat Wave Effects on Coronary Heart Disease Mortality in Beijing, China: A Time Series Study

    PubMed Central

    Tian, Zhaoxing; Li, Shanshan; Zhang, Jinliang; Guo, Yuming

    2013-01-01

    Background There is limited evidence for the impacts of heat waves on coronary heart disease (CHD) mortality in Beijing, capital city of China. Objectives We aimed to find a best heat wave definition for CHD mortality; and explore the characteristic of heat wave effects on CHD in Beijing, China. Methods We obtained daily data on weather and CHD mortality in Beijing for years 2000–2011. A quasi-Poisson regression model was used to assess the short-term impact of heat waves on CHD mortality in hot season (May–September), while controlling for relative humidity, day of the week, long-term trend and season. We compared 18 heat wave definitions by combining heat wave thresholds (87.5th, 90.0th, 92.5th, 95th, 97.5th, and 99th percentile of daily mean temperature) with different duration days (≥ 2 to ≥ 4 days), using Akaike information criterion for quasi-Poisson. We examined whether heat wave effects on CHD mortality were modified by heat wave duration and timing. Results Heat wave definition using 97.5th percentile of daily mean temperature (30.5 °C) and duration ≥ 2 days produced the best model fit. Based on this heat wave definition, we found that men and elderly were sensitive to the first heat waves of the season, while women and young were sensitive to the second heat waves. In general, the longer duration of heat waves increased the risks of CHD mortality more than shorter duration for elderly. The first two days of heat waves had the highest impact on CHD mortality. Women and elderly were at higher risks than men and young when exposed to heat waves, but the effect differences were not statistically significant. Conclusions Heat waves had significant impact on CHD mortality. This finding may have implications for policy making towards protecting human health from heat waves. PMID:24098818

  11. A 17-fold increase of trifluoroacetic acid in landscape waters of Beijing, China during the last decade.

    PubMed

    Zhai, Zihan; Wu, Jing; Hu, Xia; Li, Li; Guo, Junyu; Zhang, Boya; Hu, Jianxin; Zhang, Jianbo

    2015-06-01

    The concentrations of trifluoroacetic acid (TFA) were measured in urban landscape waters, tap water and snows in Beijing, China in 2012. Compared with the 2002 measurements, a 17-fold increase from 23-98ngL(-1) to 345-828ngL(-1) was observed for TFA concentrations in urban landscape waters, and an obvious increase from not detected (n.d.) to 155ngL(-1) occurred to TFA in tap water. By flux estimation between air and water interface, the remarkable increase of TFA was attributable to dry and wet deposition. The quantitative water-air-sediment interaction (QWASI) model simulated TFAs in various environmental media and showed that, over 99% of TFA distributed in water bodies. Our results recommend that measures are needed to control the increase of TFA in China. PMID:25262947

  12. Health risks of heavy metals in contaminated soils and food crops irrigated with wastewater in Beijing, China.

    PubMed

    Khan, S; Cao, Q; Zheng, Y M; Huang, Y Z; Zhu, Y G

    2008-04-01

    Consumption of food crops contaminated with heavy metals is a major food chain route for human exposure. We studied the health risks of heavy metals in contaminated food crops irrigated with wastewater. Results indicate that there is a substantial buildup of heavy metals in wastewater-irrigated soils, collected from Beijing, China. Heavy metal concentrations in plants grown in wastewater-irrigated soils were significantly higher (PChina and the World Health Organization (WHO). Furthermore, this study highlights that both adults and children consuming food crops grown in wastewater-irrigated soils ingest significant amount of the metals studied. However, health risk index values of less than 1 indicate a relative absence of health risks associated with the ingestion of contaminated vegetables. PMID:17720286

  13. Characteristic and potential sources of polychlorinated dibenzo-P-dioxins and dibenzofurans in agricultural soils in Beijing, China.

    PubMed

    Li, Wei; Li, Chaoqin; Chen, Zuosheng; Cai, Zongwei

    2014-09-01

    Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in 25 background and 80 agricultural soil samples collected from 21 sites in Beijing, China. The levels of PCDD/Fs in the north agricultural soils were low (0.15-0.58 ng international toxic equivalent quantity [I-TEQ]/kg), which were comparable with those of the background soils (0.091-0.35 ng I-TEQ/kg). In the southern agricultural soils, however, concentrations were several times higher (0.27-3.3 ng I-TEQ/kg). Comparison of PCDD/Fs congener compositions between possible sources and samples indicated that agricultural soils in Beijing had not been contaminated by the 3 main PCDD/F contamination sources in China--ferrous and nonferrous metal, waste incineration, and power generation. They had, however, been slightly contaminated by the impurities of some organochlorine pesticides, such as sodium pentachlorophenate, and by open burning of biomass, vehicle exhaust, atmospheric deposition, sediment, and sewage sludge. These results have been supported by the principal components analysis. PMID:24863628

  14. Gas and particle size distributions of polychlorinated naphthalenes in the atmosphere of Beijing, China.

    PubMed

    Zhu, Qingqing; Zhang, Xian; Dong, Shujun; Gao, Lirong; Liu, Guorui; Zheng, Minghui

    2016-05-01

    Polychlorinated naphthalenes (PCNs) were listed as persistent organic pollutants in the Stockholm Convention in 2015. Despite numerous studies on PCNs, little is known about their occurrence in atmospheric particulate matter of different sizes. In this study, 49 PCN congeners were investigated for their concentrations and size-specific distributions in an urban atmosphere, and preliminary exposure assessments were conducted. Ambient air samples were collected using a high-volume cascade impactor for division into a gas fraction and four particle size fractions. Samples were collected from October 2013 to June 2014 at an urban site in Beijing, China. The concentration range for PCNs in the atmosphere (gas + particle fractions) was 6.77-25.90 pg/m(3) (average 16.28 pg/m(3)). The particle-bound concentration range was 0.17-2.78 pg/m(3) (average 1.73 pg/m(3)). Therefore, PCNs were mainly found in the gas phase. The concentrations of PCNs in a fraction increased as the particle size decreased (dae > 10 μm, 10 μm ≥ dae > 2.5 μm, 2.5 μm ≥ dae > 1.0 μm and dae ≤ 1.0 μm). Consequently, PCNs were ubiquitous in inhalable fine particles, and the ΣPCNs associated with PM1.0 and PM2.5 reached 68.4% and 84.3%, respectively. Tetra-CNs and penta-CNs (the lower chlorinated homologues) predominated in the atmosphere. The homologue profiles in different size particles were almost similar, but the particulate profiles were different from those in the gas phase. Among the individual PCNs identified, CN38/40, CN52/60 and CN75 were the dominant compounds in the atmosphere. CN66/67 and CN73 collectively accounted for most of the total dioxin-like TEQ concentrations of the PCNs. Exposure to toxic compounds, such as PCNs present in PM1.0 or PM2.5, may affect human health. This work presents the first data on size-specific distributions of PCNs in the atmosphere. PMID:26840526

  15. 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…

  16. Dust aerosol properties and radiative forcing observed in spring during 2001-2014 over urban Beijing, China.

    PubMed

    Yu, Xingna; Lü, Rui; Kumar, K Raghavendra; Ma, Jia; Zhang, Qiuju; Jiang, Yilun; Kang, Na; Yang, Suying; Wang, Jing; Li, Mei

    2016-08-01

    The ground-based characteristics (optical and radiative properties) of dust aerosols measured during the springtime between 2001 and 2014 were investigated over urban Beijing, China. The seasonal averaged aerosol optical depth (AOD) during spring of 2001-2014 was about 0.78 at 440 nm. During dust days, higher AOD occurred associated with lower Ångström exponent (AE). The mean AE440-870 in the springtime was about 1.0, indicating dominance of fine particles over the region. The back-trajectory analysis revealed that the dust was transported from the deserts of Inner Mongolia and Mongolia arid regions to Beijing. The aerosol volume size distribution showed a bimodal distribution pattern, with its highest peak observed in coarse mode for all episodes (especially for dust days with increased volume concentration). The single scattering albedo (SSA) increased with wavelength on dust days, indicating the presence of more scattering particles. Furthermore, the complex parts (real and imaginary) of refractive index showed distinct characteristics with lower imaginary values (also scattering) on dust days. The shortwave (SW; 0.2-4.0 μm) and longwave (LW; 4-100 μm) aerosol radiative forcing (ARF) values were computed from the Santa Barbara DISORT Atmospheric Radiative Transfer (SBDART) model both at the top of atmosphere (TOA) and the bottom of atmosphere (BOA) during dust and non-dust (dust free) days, and the corresponding heating rates and forcing efficiencies were also estimated. The SW (LW) ARF, therefore, produced significant cooling (warming) effects at both the TOA and the BOA over Beijing. PMID:27117151

  17. Compensatory Mutations of Rifampin Resistance Are Associated with Transmission of Multidrug-Resistant Mycobacterium tuberculosis Beijing Genotype Strains in China.

    PubMed

    Li, Qin-Jing; Jiao, Wei-Wei; Yin, Qing-Qin; Xu, Fang; Li, Jie-Qiong; Sun, Lin; Xiao, Jing; Li, Ying-Jia; Mokrousov, Igor; Huang, Hai-Rong; Shen, A-Dong

    2016-05-01

    Mycobacterium tuberculosis can acquire resistance to rifampin (RIF) through mutations in the rpoB gene. This is usually accompanied by a fitness cost, which, however, can be mitigated by secondary mutations in the rpoA or rpoC gene. This study aimed to identify rpoA and rpoC mutations in clinical M. tuberculosis isolates in northern China in order to clarify their role in the transmission of drug-resistant tuberculosis (TB). The study collection included 332 RIF-resistant and 178 RIF-susceptible isolates. The majority of isolates belonged to the Beijing genotype (95.3%, 486/510 isolates), and no mutation was found in rpoA or rpoC of the non-Beijing genotype strains. Among the Beijing genotype strains, 27.8% (89/320) of RIF-resistant isolates harbored nonsynonymous mutations in the rpoA (n = 6) or rpoC (n = 83) gene. The proportion of rpoC mutations was significantly higher in new cases (P = 0.023) and in strains with the rpoB S531L mutation (P < 0.001). In addition, multidrug-resistant (MDR) strains with rpoC mutations were significantly associated with 24-locus mycobacterial interspersed repetitive-unit-variable-number tandem-repeat clustering (P = 0.016). In summary, we believe that these findings indirectly suggest an epistatic interaction of particular mutations related to RIF resistance and strain fitness and, consequently, the role of such mutations in the spread of MDR M. tuberculosis strains. PMID:26902762

  18. 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

  19. Aging Will Amplify the Heat-Related Mortality Risk Under a Changing Climate: Projection for the Elderly in Beijing, China

    NASA Technical Reports Server (NTRS)

    Li, Tiantian; Horton, Radley M.; Bader, Daniel A.; Zhou, Maigeng; Liang, Xudong; Ban, Jie; Sun, Qinghua; Kinney, Patrick L.

    2016-01-01

    An aging population could substantially enhance the burden of heat-related health risks in a warming climate because of their higher susceptibility to extreme heat health effects. Here, we project heatrelated mortality for adults 65 years and older in Beijing China across 31 downscaled climate models and 2 representative concentration pathways (RCPs) in the 2020s, 2050s, and 2080s. Under a scenario of medium population and RCP8.5, by the 2080s, Beijing is projected to experience 14,401 heat-related deaths per year for elderly individuals, which is a 264.9% increase compared with the 1980s. These impacts could be moderated through adaptation. In the 2080s, even with the 30% and 50% adaptation rate assumed in our study, the increase in heat-related death is approximately 7.4 times and 1.3 times larger than in the 1980s respectively under a scenario of high population and RCP8.5. These findings could assist countries in establishing public health intervention policies for the dual problems of climate change and aging population. Examples could include ensuring facilities with large elderly populations are protected from extreme heat (for example through back-up power supplies and/or passive cooling) and using databases and community networks to ensure the home-bound elderly are safe during extreme heat events.

  20. Aging Will Amplify the Heat-related Mortality Risk under a Changing Climate: Projection for the Elderly in Beijing, China.

    PubMed

    Li, Tiantian; Horton, Radley M; Bader, Daniel A; Zhou, Maigeng; Liang, Xudong; Ban, Jie; Sun, Qinghua; Kinney, Patrick L

    2016-01-01

    An aging population could substantially enhance the burden of heat-related health risks in a warming climate because of their higher susceptibility to extreme heat health effects. Here, we project heat-related mortality for adults 65 years and older in Beijing China across 31 downscaled climate models and 2 representative concentration pathways (RCPs) in the 2020s, 2050s, and 2080s. Under a scenario of medium population and RCP8.5, by the 2080s, Beijing is projected to experience 14,401 heat-related deaths per year for elderly individuals, which is a 264.9% increase compared with the 1980s. These impacts could be moderated through adaptation. In the 2080s, even with the 30% and 50% adaptation rate assumed in our study, the increase in heat-related death is approximately 7.4 times and 1.3 times larger than in the 1980s respectively under a scenario of high population and RCP8.5. These findings could assist countries in establishing public health intervention policies for the dual problems of climate change and aging population. Examples could include ensuring facilities with large elderly populations are protected from extreme heat (for example through back-up power supplies and/or passive cooling) and using databases and community networks to ensure the home-bound elderly are safe during extreme heat events. PMID:27320724

  1. Aging Will Amplify the Heat-related Mortality Risk under a Changing Climate: Projection for the Elderly in Beijing, China

    PubMed Central

    Li, Tiantian; Horton, Radley M.; Bader, Daniel A.; Zhou, Maigeng; Liang, Xudong; Ban, Jie; Sun, Qinghua; Kinney, Patrick L.

    2016-01-01

    An aging population could substantially enhance the burden of heat-related health risks in a warming climate because of their higher susceptibility to extreme heat health effects. Here, we project heat-related mortality for adults 65 years and older in Beijing China across 31 downscaled climate models and 2 representative concentration pathways (RCPs) in the 2020s, 2050s, and 2080s. Under a scenario of medium population and RCP8.5, by the 2080s, Beijing is projected to experience 14,401 heat-related deaths per year for elderly individuals, which is a 264.9% increase compared with the 1980s. These impacts could be moderated through adaptation. In the 2080s, even with the 30% and 50% adaptation rate assumed in our study, the increase in heat-related death is approximately 7.4 times and 1.3 times larger than in the 1980s respectively under a scenario of high population and RCP8.5. These findings could assist countries in establishing public health intervention policies for the dual problems of climate change and aging population. Examples could include ensuring facilities with large elderly populations are protected from extreme heat (for example through back-up power supplies and/or passive cooling) and using databases and community networks to ensure the home-bound elderly are safe during extreme heat events. PMID:27320724

  2. Aging Will Amplify the Heat-related Mortality Risk under a Changing Climate: Projection for the Elderly in Beijing, China

    NASA Astrophysics Data System (ADS)

    Li, Tiantian; Horton, Radley M.; Bader, Daniel A.; Zhou, Maigeng; Liang, Xudong; Ban, Jie; Sun, Qinghua; Kinney, Patrick L.

    2016-06-01

    An aging population could substantially enhance the burden of heat-related health risks in a warming climate because of their higher susceptibility to extreme heat health effects. Here, we project heat-related mortality for adults 65 years and older in Beijing China across 31 downscaled climate models and 2 representative concentration pathways (RCPs) in the 2020s, 2050s, and 2080s. Under a scenario of medium population and RCP8.5, by the 2080s, Beijing is projected to experience 14,401 heat-related deaths per year for elderly individuals, which is a 264.9% increase compared with the 1980s. These impacts could be moderated through adaptation. In the 2080s, even with the 30% and 50% adaptation rate assumed in our study, the increase in heat-related death is approximately 7.4 times and 1.3 times larger than in the 1980s respectively under a scenario of high population and RCP8.5. These findings could assist countries in establishing public health intervention policies for the dual problems of climate change and aging population. Examples could include ensuring facilities with large elderly populations are protected from extreme heat (for example through back-up power supplies and/or passive cooling) and using databases and community networks to ensure the home-bound elderly are safe during extreme heat events.

  3. Occurrence, distribution and seasonal variation of organophosphate flame retardants and plasticizers in urban surface water in Beijing, China.

    PubMed

    Shi, Yali; Gao, Lihong; Li, Wenhui; Wang, Yuan; Liu, Jiemin; Cai, Yaqi

    2016-02-01

    The occurrence, spatial distribution and seasonal variation of 14 organophosphate esters (OPEs) were investigated in urban surface water (river and lake water) from July 2013 to June 2014 in Beijing, China. Sewage influent and effluent samples, as well as rainwater and road runoff samples were also analyzed as the potential sources of OPEs in surface water. Tris(2-chloro-1-methylethyl) phosphate (TCPP) and tris(2-chloroethyl) phosphate (TCEP) were the most abundant OPEs with the average concentrations of 291 ng L(-1) and 219 ng L(-1), respectively. Relatively high concentrations of OPEs were detected in rivers located at southern and eastern urban of Beijing, which was probably attributed to the treated and untreated sewage discharge. Besides, higher levels of OPEs were observed in urban surface water in the summer, and the wet deposition (rainfall) was confirmed to be an important factor for this observation. Risk assessment showed low or medium risk of OPEs for the organisms (algae, crustacean and fish). PMID:26618261

  4. Spatial and temporal variations in NO(2) distributions over Beijing, China measured by imaging differential optical absorption spectroscopy.

    PubMed

    Lee, Hanlim; Kim, Young J; Jung, Jinsang; Lee, Chulkyu; Heue, Klaus-Peter; Platt, Ulrich; Hu, Min; Zhu, Tong

    2009-04-01

    During the CAREBEIJING campaign in 2006, imaging differential optical absorption spectroscopy (I-DOAS) measurements were made from 08:00 to 16:00 on September 9 and 10 over Beijing, China. Detailed images of the near-surface NO(2) differential slant column density (DSCD) distribution over Beijing were obtained. Images with less than a 30-min temporal resolution showed both horizontal and vertical variations in NO(2) distributions. For DSCD to mixing ratio conversion, path length along the lines of I-DOAS lines of sight was estimated using the light-extinction coefficient and Angstrom exponent data obtained by a transmissometer and a sunphotometer, respectively. Mixing ratios measured by an in-situ NO(2) analyzer were compared with those estimated by the I-DOAS instrument. The obtained temporal and spatial variations in NO(2) distributions measured by I-DOAS for the two days are interpreted with consideration of the locations of the major NO(x) sources and local wind conditions. I-DOAS measurements have been applied in this study for estimating NO(2) distribution over an urban area with multiple and distributed emission sources. Results are obtained for estimated temporal and spatial NO(2) distributions over the urban atmosphere; demonstrating the capability of the I-DOAS technique. We discuss in this paper the use of I-DOAS measurements to estimate the NO(2) distribution over an urban area with multiple distributed emission sources. PMID:19111964

  5. Survey of nine abortifacient infectious agents in aborted bovine fetuses from dairy farms in Beijing, China, by PCR.

    PubMed

    Yang, Na; Cui, Xia; Qian, Weifeng; Yu, Shanshan; Liu, Qun

    2012-03-01

    Abortion in dairy cattle causes considerable economic losses to the dairy industry. Aborted fetuses and samples from the corresponding aborting dams from 12 dairy herds in Beijing were tested for 9 abortifacient infectious pathogens by PCR between 2008 and 2010. From a total of 80 abortion cases collected during this period, infectious agents were detected in 45 (56.3%) cases, 22 (48.9%) of which represented co-infections with two or three infectious agents. The detected pathogens included infectious bovine rhinotracheitis virus (36.3%) and Neospora caninum (31.3%), followed by bovine viral diarrhoea virus (7.5%), Brucella abortus (6.3%), Tritrichomonas foetus (5%) and Toxoplasma gondii (1.3%). Campylobacter fetus, Coxiella burnetii and Chlamydophila psittaci were not detected in any abortion case. Findings from this study indicated that infectious bovine rhinotracheitis virus and Neospora caninum were the main potential causes of abortions in Beijing dairy herds, whereas the bacterial pathogens were not, in contrast to reports from other countries. This is the first study to test nine abortifacient infectious agents by PCR at the same time, and it is also the first time to report the involvement of a variety of infectious agents in bovine abortion cases in China. PMID:22366134

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

    PubMed

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

    2012-09-18

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

  7. PM2.5 Spatiotemporal Variations and the Relationship with Meteorological Factors during 2013-2014 in Beijing, China

    PubMed Central

    Wang, Chao; Xu, Qin; Wang, Wei; Luo, Yanxia; Tao, Lixin; Gao, Qi; Guo, Jin; Chen, Sipeng; Cao, Kai; Liu, Long; Gao, Ni; Liu, Xiangtong; Yang, Kun; Yan, Aoshuang; Guo, Xiuhua

    2015-01-01

    Objective Limited information is available regarding spatiotemporal variations of particles with median aerodynamic diameter < 2.5 μm (PM2.5) at high resolutions, and their relationships with meteorological factors in Beijing, China. This study aimed to detect spatiotemporal change patterns of PM2.5 from August 2013 to July 2014 in Beijing, and to assess the relationship between PM2.5 and meteorological factors. Methods Daily and hourly PM2.5 data from the Beijing Environmental Protection Bureau (BJEPB) were analyzed separately. Ordinary kriging (OK) interpolation, time-series graphs, Spearman correlation coefficient and coefficient of divergence (COD) were used to describe the spatiotemporal variations of PM2.5. The Kruskal-Wallis H test, Bonferroni correction, and Mann-Whitney U test were used to assess differences in PM2.5 levels associated with spatial and temporal factors including season, region, daytime and day of week. Relationships between daily PM2.5 and meteorological variables were analyzed using the generalized additive mixed model (GAMM). Results Annual mean and median of PM2.5 concentrations were 88.07 μg/m3 and 71.00 μg/m3, respectively, from August 2013 to July 2014. PM2.5 concentration was significantly higher in winter (P < 0.0083) and in the southern part of the city (P < 0.0167). Day to day variation of PM2.5 showed a long-term trend of fluctuations, with 2–6 peaks each month. PM2.5 concentration was significantly higher in the night than day (P < 0.0167). Meteorological factors were associated with daily PM2.5 concentration using the GAMM model (R2 = 0.59, AIC = 7373.84). Conclusion PM2.5 pollution in Beijing shows strong spatiotemporal variations. Meteorological factors influence the PM2.5 concentration with certain patterns. Generally, prior day wind speed, sunlight hours and precipitation are negatively correlated with PM2.5, whereas relative humidity and air pressure three days earlier are positively correlated with PM2.5. PMID

  8. Inhalable particulate matter and mitochondrial DNA copy number in highly exposed individuals in Beijing, China: a repeated-measure study

    PubMed Central

    2013-01-01

    Background Mitochondria are both a sensitive target and a primary source of oxidative stress, a key pathway of air particulate matter (PM)-associated diseases. Mitochondrial DNA copy number (MtDNAcn) is a marker of mitochondrial damage and malfunctioning. We evaluated whether ambient PM exposure affects MtDNAcn in a highly-exposed population in Beijing, China. Methods The Beijing Truck Driver Air Pollution Study was conducted shortly before the 2008 Beijing Olympic Games (June 15-July 27, 2008) and included 60 truck drivers and 60 office workers. Personal PM2.5 and elemental carbon (EC, a tracer of traffic particles) were measured during work hours using portable monitors. Post-work blood samples were obtained on two different days. Ambient PM10 was averaged from 27 monitoring stations in Beijing. Blood MtDNAcn was determined by real-time PCR and examined in association with particle levels using mixed-effect models. Results In all participants combined, MtDNAcn was negatively associated with personal EC level measured during work hours (β=−0.059, 95% CI: -0.011; -0.0006, p=0.03); and 5-day (β=−0.017, 95% CI: -0.029;-0.005, p=0.01) and 8-day average ambient PM10 (β=−0.008, 95% CI: -0.043; -0.008, p=0.004) after adjusting for possible confounding factors, including study groups. MtDNAcn was also negatively associated among office workers with EC (β=−0.012, 95% CI: -0.022;-0.002, p=0.02) and 8-day average ambient PM10 (β=−0.030, 95% CI: -0.051;-0.008, p=0.007). Conclusions We observed decreased blood MtDNAcn in association with increased exposure to EC during work hours and recent ambient PM10 exposure. Our results suggest that MtDNAcn may be influenced by particle exposures. Further studies are required to determine the roles of MtDNAcn in the etiology of particle-related diseases. PMID:23628000

  9. Fine Particulate Air Pollution and Hospital Emergency Room Visits for Respiratory Disease in Urban Areas in Beijing, China, in 2013

    PubMed Central

    Wang, Shuo; Wang, Chao; Huang, Fangfang; Gao, Qi; Wu, Lijuan; Tao, Lixin; Guo, Jin; Wang, Wei; Guo, Xiuhua

    2016-01-01

    Background Heavy fine particulate matter (PM2.5) air pollution occurs frequently in China. However, epidemiological research on the association between short-term exposure to PM2.5 pollution and respiratory disease morbidity is still limited. This study aimed to explore the association between PM2.5 pollution and hospital emergency room visits (ERV) for total and cause-specific respiratory diseases in urban areas in Beijing. Methods Daily counts of respiratory ERV from Jan 1 to Dec 31, 2013, were obtained from ten general hospitals located in urban areas in Beijing. Concurrently, data on PM2.5 were collected from the Beijing Environmental Protection Bureau, including 17 ambient air quality monitoring stations. A generalized-additive model was used to explore the respiratory effects of PM2.5, after controlling for confounding variables. Subgroup analyses were also conducted by age and gender. Results A total of 92,464 respiratory emergency visits were recorded during the study period. The mean daily PM2.5 concentration was 102.1±73.6 μg/m3. Every 10 μg/m3 increase in PM2.5 concentration at lag0 was associated with an increase in ERV, as follows: 0.23% for total respiratory disease (95% confidence interval [CI]: 0.11%-0.34%), 0.19% for upper respiratory tract infection (URTI) (95%CI: 0.04%-0.35%), 0.34% for lower respiratory tract infection (LRTI) (95%CI: 0.14%-0.53%) and 1.46% for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) (95%CI: 0.13%-2.79%). The strongest association was identified between AECOPD and PM2.5 concentration at lag0-3 (3.15%, 95%CI: 1.39%-4.91%). The estimated effects were robust after adjusting for SO2, O3, CO and NO2. Females and people 60 years of age and older demonstrated a higher risk of respiratory disease after PM2.5 exposure. Conclusion PM2.5 was significantly associated with respiratory ERV, particularly for URTI, LRTI and AECOPD in Beijing. The susceptibility to PM2.5 pollution varied by gender and age. PMID

  10. Temporal trends in daily dietary intakes of DDTs and HCHs in urban populations from Beijing and Shenyang, China.

    PubMed

    Yu, Yanxin; Wang, Bin; Wang, Xilong; Liu, Wenxin; Cao, Jun; Wong, Minghong; Tao, Shu

    2013-06-01

    The temporal trends in daily dietary exposure of the populations in Beijing and Shenyang, China to DDTs and HCHs through consumption of various food categories and the associated health risks were investigated in this work. The estimated dietary intakes of DDTs and HCHs in 2005/2007 were almost one and two orders of magnitude lower than those in 1992 and in the 1970s, respectively, revealing the historical decrease of DDT and HCH in Chinese foods after their applications were banned. The relative contributions of different foodstuffs to the overall intakes of DDTs and HCHs in the 1970s and in 1992 were very different from those in 2005/2007, mainly due to the remarkable concentration variance in foodstuffs and changes in diet habit of population. According to the hazard guidelines, it is concluded that intakes of these two pesticides in 2005/2007 may not exert adverse effects on human health. PMID:23427859

  11. Tempo-Spatial Patterns of Land Use Changes and Urban Development in Globalizing China: A Study of Beijing

    PubMed Central

    Xie, Yichun; Fang, Chuanglin; Lin, George C.S.; Gong, Hongmian; Qiao, Biao

    2007-01-01

    This study examines the temporal and spatial changes in land use as a consequence of rapid urban development in the city of Beijing. Using a combination of techniques of remote sensing and GIS, the study identifies a substantial loss of plain dryland and a phenomenal expansion of urban construction land over the recent decade. Geographically, there is a clear shifting of urban construction land from the inner city to the outskirts as a consequence of suburbanization. The outward expansion of the ring-road system is found to be one of the most important driving forces explaining the temporal and spatial pattern of land use change. The uneven distribution of population stands as another factor with significant correlation with land use change. The application of the techniques of remote sensing and GIS can enhance the precision and comparability of research on land use change and urban transformation in China.

  12. Watershed-scale assessment of arsenic and metal contamination in the surface soils surrounding Miyun Reservoir, Beijing, China.

    PubMed

    Luo, Wei; Lu, Yonglong; Zhang, Yan; Fu, Wenyou; Wang, Bin; Jiao, Wentao; Wang, Guang; Tong, Xiaojuan; Giesy, John P

    2010-12-01

    Concentrations of As and selected metals were determined in surface soils of the Miyun Reservoir watershed of Beijing, China. The degree to which concentrations of As and metals exceeded the corresponding background concentration of soils was: Cr>Cu>Zn>As>Ni with no apparent anthropogenic contamination with Cd and Pb. Based on the results of a combination of multivariate statistics and geostatistical analysis, greater concentrations of Cr and Ni in soils were determined to be primarily from iron ore mining near where the Chaohe River enters the northeast portion of the reservoir. Agricultural activities were responsible for the observed elevated concentrations of Cu and Zn in soils. Relatively great concentrations of As were found in soils near the upstream regions of the Baihe River in Chicheng County where small gold mining activities have taken place. The greatest potential for adverse effects of Cr and Cu occurred along the eastern shore of Miyun Reservoir. PMID:20702025

  13. A report from the 42nd Annual Meeting of the International Continence Society (October 15-19 - Beijing, China).

    PubMed

    Rabasseda, X

    2012-11-01

    As Beijing was selected as the site for this year's International Continence Society (ICS) meeting, crowds of locals navigating through the subway train lines and tourists lining up for access to the Forbidden City and other landmarks were joined by a less numerous but a still significant number of researchers, scientists and practitioners working on urinary tract diseases and disorders going to the China National Convention Center to attend the podium and poster sessions. Located next to the Bird's Nest Olympic stadium and offering grand views over the Olympic park from the upper floor where non-discussion posters were displayed, the modern facilities allowed for a smooth, seamless meeting during which a number of highly relevant new findings were discussed. The following report summarizes selected presentations on pharmacotherapy and drug candidates for overactive bladder and other common diseases of the urinary tract. PMID:23170310

  14. 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.

  15. The collection system for residential recyclables in communities in Haidian District, Beijing: a possible approach for China recycling.

    PubMed

    Wang, Jia; Han, Ling; Li, Shushu

    2008-01-01

    Recycling and reusing recyclables is an important way to solve the municipal solid waste (MSW) problem. As the collection of solid waste takes up the largest percentage of MSW management budgets, improving the collection of recyclables is important. Since the decline of government-run waste buying depots in the late 1980s, the collection of recyclables from households and waste deposit sites in China is done by buyers with small informal bases and waste pickers, who are usually unskilled rural people who have come to the cities. Because of this, the current system is seen to have social problems. So, the recyclable collection system has both social as well as economic significance. China is in the process of rapid industrialization and urbanization, and a new mode of community collection system is emerging. It operates by market mechanisms, with waste collection companies that are supported by the municipal government, establishing recycle service sites, and employing workers to buy recyclables door-to-door. This paper is a case study of the new system in the Haidian District, Beijing. It summarizes the system, compares it to experiences in other countries and discusses whether the new approach contributes to resources recycling in China. PMID:17967528

  16. Chi-squared Automatic Interaction Detection Decision Tree Analysis of Risk Factors for Infant Anemia in Beijing, China

    PubMed Central

    Ye, Fang; Chen, Zhi-Hua; Chen, Jie; Liu, Fang; Zhang, Yong; Fan, Qin-Ying; Wang, Lin

    2016-01-01

    Background: In the past decades, studies on infant anemia have mainly focused on rural areas of China. With the increasing heterogeneity of population in recent years, available information on infant anemia is inconclusive in large cities of China, especially with comparison between native residents and floating population. This population-based cross-sectional study was implemented to determine the anemic status of infants as well as the risk factors in a representative downtown area of Beijing. Methods: As useful methods to build a predictive model, Chi-squared automatic interaction detection (CHAID) decision tree analysis and logistic regression analysis were introduced to explore risk factors of infant anemia. A total of 1091 infants aged 6–12 months together with their parents/caregivers living at Heping Avenue Subdistrict of Beijing were surveyed from January 1, 2013 to December 31, 2014. Results: The prevalence of anemia was 12.60% with a range of 3.47%–40.00% in different subgroup characteristics. The CHAID decision tree model has demonstrated multilevel interaction among risk factors through stepwise pathways to detect anemia. Besides the three predictors identified by logistic regression model including maternal anemia during pregnancy, exclusive breastfeeding in the first 6 months, and floating population, CHAID decision tree analysis also identified the fourth risk factor, the maternal educational level, with higher overall classification accuracy and larger area below the receiver operating characteristic curve. Conclusions: The infant anemic status in metropolis is complex and should be carefully considered by the basic health care practitioners. CHAID decision tree analysis has demonstrated a better performance in hierarchical analysis of population with great heterogeneity. Risk factors identified by this study might be meaningful in the early detection and prompt treatment of infant anemia in large cities. PMID:27174328

  17. Completeness of nutrient declarations and the average nutritional composition of pre-packaged foods in Beijing, China.

    PubMed

    Huang, Liping; Neal, Bruce; Dunford, Elizabeth; Ma, Guansheng; Wu, Jason H Y; Crino, Michelle; Trevena, Helen

    2016-12-01

    Increasing consumption of pre-packaged foods is likely an important driver of diet-related diseases in China. From January 2013 it became mandatory to provide a standardised nutrient declaration on pre-packaged foods in China. We collected data on pre-packaged foods from large chain supermarkets in Beijing in 2013, examined the completeness of the nutrient declaration of core required nutrients and summarised the average nutritional composition of 14 different major food groups. We also illustrated the potential use of the data by comparing sodium levels. Photos of 14,279 pre-packaged foods were collected from 16 chain supermarkets in Beijing. Data for 11,489 products were included in the evaluation of nutrient declarations and data for 10,048 in the summary analysis of average nutritional composition. Compliant nutrient declarations were displayed by 87% of products with 88% of foods displaying data for each of energy, protein, total fat, carbohydrate and sodium. Nutrients not required by the Chinese regulation were infrequently reported: saturated fat (12%), trans fat (17%) and sugars (11%). Mean sodium levels were higher in Chinese products compared to UK products for 8 of 11 major food categories, often markedly so (e.g. 1417 mg/100 g vs. 304 mg/100 g for convenience foods). There has been substantial uptake of the recently introduced Chinese nutrition labelling regulation which should help consumers to choose healthier foods. As the comparison against corresponding data about sodium from the United Kingdom shows, the nutrient data can also be used to identify broader opportunities for improvement of the food supply. PMID:27570732

  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%. PMID:27039059

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

    NASA Astrophysics Data System (ADS)

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

    2015-03-01

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

  20. 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.

  1. 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.

  2. An integrated MM5-CMAQ modeling approach for assessing trans-boundary PM 10 contribution to the host city of 2008 Olympic summer games—Beijing, China

    NASA Astrophysics Data System (ADS)

    Chen, D. S.; Cheng, S. Y.; Liu, L.; Chen, T.; Guo, X. R.

    In this paper, an integrated MM5-CMAQ modeling approach was employed to investigate the PM 10 air pollution issue in Beijing, China, with a focus on assessing pollution contributions from surrounding provinces. A 2-level-nested grid domain with spatial resolutions of 36 and 12 km was designed for the study region. Seven monitoring stations across Beijing municipality were selected to provide hourly PM 10 measurement data. The months of January, April, July and October in 2002 were taken as target periods for model performance evaluation. Five emission scenarios were designed and run in order to quantitatively assess the trans-boundary PM 10 contributions. The results show that, while Beijing needs to take positive steps to reduce its own pollution emissions, much effort should also be placed on demanding more pollution reduction and better environmental performance from surrounding provinces.

  3. Characterization of mutations in streptomycin-resistant Mycobacterium tuberculosis isolates in Sichuan, China and the association between Beijing-lineage and dual-mutation in gidB.

    PubMed

    Sun, Honghu; Zhang, Congcong; Xiang, Ling; Pi, Rui; Guo, Zhen; Zheng, Chao; Li, Song; Zhao, Yuding; Tang, Ke; Luo, Mei; Rastogi, Nalin; Li, Yuqing; Sun, Qun

    2016-01-01

    Mutations in rpsL, rrs, and gidB are well linked to streptomycin (STR) resistance, some of which are suggested to be potentially associated with Mycobacterium tuberculosis genotypic lineages in certain geographic regions. In this study, we aimed to investigate the mutation characteristics of streptomycin resistance and the relationship between the polymorphism of drug-resistant genes and the lineage of M. tuberculosis isolates in Sichuan, China. A total of 227 M. tuberculosis clinical isolates, including 180 STR-resistant and 47 pan-susceptible isolates, were analyzed for presence of mutations in the rpsL, rrs and gidB loci. Mutation K43R in rpsL was strongly associated with high-level streptomycin resistance (P < 0.01), while mutations in rrs and gidB potentially contributed to low-level resistance (P < 0.05). No general association was exhibited between STR resistance and Beijing genotype, however, in STR-resistant strains, Beijing genotype was significantly correlated with high-level STR resistance, as well as the rpsL mutation K43R (P < 0.01), indicating that Beijing genotype has an evolutionary advantage under streptomycin pressure. Notably, in all isolates of Beijing genotype, a dual mutation E92D (a276c) and A205A (a615g) in gidB was detected, suggesting a highly significant association between this dual mutation and Beijing genotype. PMID:26786661

  4. Atmospheric Fossil Fuel CO2 Traced by Δ(14)C in Beijing and Xiamen, China: Temporal Variations, Inland/Coastal Differences and Influencing Factors.

    PubMed

    Niu, Zhenchuan; Zhou, Weijian; Wu, Shugang; Cheng, Peng; Lu, Xuefeng; Xiong, Xiaohu; Du, Hua; Fu, Yunchong; Wang, Gehui

    2016-06-01

    One year of atmospheric Δ(14)CO2 were observed in 2014 in the inland city of Beijing and coastal city of Xiamen, China, to trace temporal CO2ff variations and to determine the factors influencing them. The average CO2ff concentrations at the sampling sites in Beijing and Xiamen were 39.7 ± 36.1 ppm and 13.6 ± 12.3 ppm, respectively. These contributed 75.2 ± 14.6% and 59.1 ± 26.8% to their respective annual ΔCO2 offsets over background CO2 concentrations. Significantly (p < 0.05) high CO2ff values were observed in winter in Beijing. We did not find any significant differences in CO2ff values between weekdays and weekends. Diurnal CO2ff variations were plainly evident, with high values between midnight and 4:00, and during morning and afternoon rush hours. The sampling site in the inland city of Beijing displayed much higher CO2ff inputs and overall temporal variations than the site in the coastal city of Xiamen. The variations of CO2ff at both sites were controlled by a combination of emission sources, topography, and atmospheric dispersion. In particular, diurnal observations at the urban site in Beijing showed that CO2ff was easily accumulated under the southeast wind conditions. PMID:27171980

  5. Long-term (2001-2012) concentrations of fine particulate matter (PM2.5) and the impact on human health in Beijing, China

    NASA Astrophysics Data System (ADS)

    Zheng, S.; Pozzer, A.; Cao, C. X.; Lelieveld, J.

    2015-05-01

    Beijing, the capital of China, is a densely populated city with poor air quality. The impact of high pollutant concentrations, in particular of aerosol particles, on human health is of major concern. The present study uses aerosol optical depth (AOD) as proxy to estimate long-term PM2.5 and subsequently estimates the premature mortality due to PM2.5. We use the AOD from 2001 to 2012 from the Aerosol Robotic Network (AERONET) site in Beijing and the ground-based PM2.5 observations from the US embassy in Beijing from 2010 to 2011 to establish a relationship between PM2.5 and AOD. By including the atmospheric boundary layer height and relative humidity in the comparative analysis, the correlation (R2) increases from 0.28 to 0.62. We evaluate 12 years of PM2.5 data for the Beijing central area using an estimated linear relationship with AOD and calculate the yearly premature mortality by different diseases attributable to PM2.5. The estimated average total mortality due to PM2.5 is about 5100 individuals per year for the period 2001-2012 in the Beijing central area, and for the period 2010-2012 the per capita mortality for all ages due to PM2.5 is around 15 per 10 000 person-years, which underscores the urgent need for air pollution abatement.

  6. Long-term (2001-2012) fine particulate matter (PM2.5) and the impact on human health in Beijing, China

    NASA Astrophysics Data System (ADS)

    Zheng, S.; Pozzer, A.; Cao, C. X.; Lelieveld, J.

    2014-11-01

    Beijing, the capital of China, is a densely populated city with poor air quality. The impact of high pollutant concentrations, in particular of aerosol particles, on human health is of major concern. The present study uses Aerosol Optical Depth (AOD) as proxy to estimate long-term PM2.5, and subsequently estimates the premature mortality due to PM2.5. We use the AOD from 2001 to 2012 from the Aerosol Robotic Network (AERONET) site in Beijing and the ground-based PM2.5 observations from the US embassy in Beijing from 2010 to 2011, to establish a relationship between PM2.5 and AOD. By including the atmospheric boundary layer height and relative humidity in the comparative analysis, the correlation (R2) increases from 0.28 to 0.62. We evaluate 12 years of PM2.5 data for the Beijing central area using an estimated linear relationship with AOD, and calculate the yearly premature mortality by different diseases attributable to PM2.5. The estimated average total mortality due to PM2.5 is about 6100 individuals yr-1 for the period 2001-2012 in the Beijing central area, and for the period 2010-2012 the per capita mortality for all ages due to PM2.5 is around 17.9 per 10 000 person-year, which underscores the urgent need for air pollution abatement.

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

    PubMed

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

    2015-08-01

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

  8. 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

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

    PubMed

    Zhang, Hua; Wen, Zong-Guo

    2014-06-01

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

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

    PubMed

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

    2016-09-01

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

  11. 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

  12. 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

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

    NASA Astrophysics Data System (ADS)

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

    2013-06-01

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

  14. Earthquake Strong Ground Motion Scenario at the 2008 Olympic Games Sites, Beijing, China

    NASA Astrophysics Data System (ADS)

    Liu, L.; Rohrbach, E. A.; Chen, Q.; Chen, Y.

    2006-12-01

    Historic earthquake record indicates mediate to strong earthquakes have been frequently hit greater Beijing metropolitan area where is going to host the 2008 summer Olympic Games. For the readiness preparation of emergency response to the earthquake shaking for a mega event in a mega city like Beijing in summer 2008, this paper tries to construct the strong ground motion scenario at a number of gymnasium sites for the 2008 Olympic Games. During the last 500 years (the Ming and Qing Dynasties) in which the historic earthquake record are thorough and complete, there are at least 12 earthquake events with the maximum intensity of VI or greater occurred within 100 km radius centered at the Tiananmen Square, the center of Beijing City. Numerical simulation of the seismic wave propagation and surface strong ground motion is carried out by the pseudospectral time domain methods with viscoelastic material properties. To improve the modeling efficiency and accuracy, a multi-scale approach is adapted: the seismic wave propagation originated from an earthquake rupture source is first simulated by a model with larger physical domain with coarser grids. Then the wavefield at a given plane is taken as the source input for the small-scale, fine grid model for the strong ground motion study at the sites. The earthquake source rupture scenario is based on two particular historic earthquake events: One is the Great 1679 Sanhe-Pinggu Earthquake (M~8, Maximum Intensity XI at the epicenter and Intensity VIII in city center)) whose epicenter is about 60 km ENE of the city center. The other one is the 1730 Haidian Earthquake (M~6, Maximum Intensity IX at the epicenter and Intensity VIII in city center) with the epicentral distance less than 20 km away from the city center in the NW Haidian District. The exist of the thick Tertiary-Quaternary sediments (maximum thickness ~ 2 km) in Beijing area plays a critical role on estimating the surface ground motion at the Olympic Games sites, which

  15. Large-scale seroprevalence analysis of human metapneumovirus and human respiratory syncytial virus infections in Beijing, China

    PubMed Central

    2011-01-01

    Background Human metapneumovirus (hMPV), a recently identified virus, causes acute respiratory tract infections (ARTIs) in infants and children. However, studies on the seroepidemeology of hMPV are very limited in China. To assess the seroprevalence of hMPV infection in China, we tested a total of 1,156 serum specimens for the presence of anti-hMPV IgG antibody in children and adults free of acute respiratory illness in Beijing, China by using hMPV nucleocapsid (N) protein as an antigen. As a control, we used the human serum antibody against the N protein of human respiratory syncytial virus (hRSV), the most important viral agent responsible for ARIs in children. Results The seropositive rate for hMPV increased steadily with age from 67% at 1-6 mo to 100% at age 20. However, the rate dropped slightly between 6 mo and 1 yr of age. The seropositive rate for hRSV also increased steadily with age from 71% at 1-6 mo to 100% at age 20. In children aged six months to six years, the seropositive rates for the anti-hRSV IgG antibody were significantly higher than those for hMPV. Additionally, IgG antibody titers to hMPV and hRSV were significantly higher in adults than in young children. Consistent with the seropositive rates, the geometric mean titer of anti-hMPV IgG antibody was lower than that of anti-hRSV IgG antibody in children aged six months to six years. Conclusions Our results indicate that similar to hRSV, exposure to hMPV is ubiquitous in the Beijing population. However, the seroprevalence of anti-hMPV IgG antibody is lower than that of hRSV in children between six months and six years old, which suggests a different number of repeat infections or a different response to infections. PMID:21310026

  16. A study on the trends of vehicular emissions in the Beijing-Tianjin-Hebei (BTH) region, China

    NASA Astrophysics Data System (ADS)

    Lang, Jianlei; Cheng, Shuiyuan; Wei, Wei; Zhou, Ying; Wei, Xiao; Chen, Dongsheng

    2012-12-01

    This paper aims to study the vehicular emissions trends in the Beijing-Tianjin-Hebei (BTH) region, located in northern China. The multiyear emission inventories of NOX, CO, VOC and PM10 from road vehicles in the period 1999-2010 were developed by the COPERT IV model. Results show that vehicular emissions of CO and VOC have decreased by annual average change rates (AACR) of -3.1% to -5.2% and -4.4% to -6.9% in the study area, respectively. However, due to the rapid development of freight traffic, emissions of NOX and PM10 have kept increasing in Tianjin and Hebei. Based on the vehicular emission inventories, trends of emission levels for vehicles with different standards, as well as the overall effects of implementing vehicular emission mitigation strategies were assessed. It is suggested that passenger cars (PC) with Euro 0 and Euro I standards, which were at higher emission level in the PC fleet, should be gradually eliminated. Although the increasing rates (IR) of emissions from PC were lower than those of the PC population, the sharp growth of PC population in recent years contributed to a remarkable increase of emissions, weakening the overall mitigation effect. Total vehicle population capacity and other mitigation measures should be studied in China in order to develop new and more effective vehicular emission control strategies.

  17. Occurrence and distribution of organophosphate triesters and diesters in sludge from sewage treatment plants of Beijing, China.

    PubMed

    Gao, Lihong; Shi, Yali; Li, Wenhui; Liu, Jiemin; Cai, Yaqi

    2016-02-15

    The occurrence and distribution of 14 organophosphate (OP) triesters and 5 diesters were investigated in sludge from eight sewage treatment plants (STPs) in Beijing, China, during 2008-2014. Tri(2-ethylhexyl) phosphate (TEHP) and tri-m-cresyl phosphate (TCrP) were the predominant triesters with the average concentration of 233-137 μg/kg, respectively. Also, the polar and hydrophilic trimethyl phosphate (TMP) and triethyl phosphate (TEP) were detected in 19% and 74% of sludge samples, respectively. Three of five diesters were detected in sludge samples, and di(2-ethylhexyl) phosphate (DEHP) revealed the highest average concentration of 96.0 μg/kg, followed by diphenyl phosphate (DPhP, 18.0 μg/kg). The levels of OP triesters in sludge varied with the compositions of the sewage and treatment capacity of STPs, as well as the adjacent sources. In comparison with that in the former years, relatively higher concentration of total OP triesters in sludge was observed in 2014, which is consistent with the rapid growth in consumption of these chemicals in China. Finally, environmental risk assessment indicated potential harmful effects of OP triesters on soil microorganisms after sludge landfill or fertilization. PMID:26657359

  18. Health risk assessment of heavy metals in soils and vegetables from wastewater irrigated area, Beijing-Tianjin city cluster, China.

    PubMed

    Wang, Yanchun; Qiao, Min; Liu, Yunxia; Zhu, Yongguan

    2012-01-01

    The possible health risks of heavy metals contamination to local population through food chain were evaluated in Beijing and Tianjin city cluster, China, where have a long history of sewage irrigation. The transfer factors (TF) for heavy metals from soil to vegetables for six elements including Cu, Zn, Pb, Cr, As and Cd were calculated and the pollution load indexes (PLI) were also assessed. Results indicate that only Cd exceeded the maximum acceptable limit in these sites. So far, the heavy metal concentrations in soils and vegetables were all below the permissible limits set by the Ministry of Environmental Protection of China and World Health Organization. The transfer factors of six heavy metals showed the trend as Cd > Zn > Cu > Pb > As > Cr, which were dependent on the vegetable species. The estimated dietary intakes of Cu, Zn, Pb, Cr, As and Cd were far below the tolerable limits and the target hazard quotient (THQ) values were less than 1, which suggested that the health risks of heavy metals exposure through consuming vegetables were generally assumed to be safe. PMID:22894104

  19. Comparison of Hourly PM2.5 Observations Between Urban and Suburban Areas in Beijing, China.

    PubMed

    Yao, Ling; Lu, Ning; Yue, Xiafang; Du, Jia; Yang, Cundong

    2015-10-01

    Hourly PM2.5 observations collected at 12 stations over a 1-year period are used to identify variations between urban and suburban areas in Beijing. The data demonstrates a unique monthly variation form, as compared with other major cities. Urban areas suffer higher PM2.5 concentration (about 92 μg/m³) than suburban areas (about 77 μg/m³), and the average PM2.5 concentration in cold season (about 105 μg/m³) is higher than warm season (about 78 μg/m³). Hourly PM2.5 observations exhibit distinct seasonal, diurnal and day-of-week variations. The diurnal variation of PM2.5 is observed with higher concentration at night and lower value at daytime, and the cumulative growth of nighttime (22:00 p.m. in winter) PM2.5 concentration maybe due to the atmospheric stability. Moreover, annual average PM2.5 concentrations are about 18 μg/m³ higher on weekends than weekdays, consistent with driving restrictions on weekdays. Additionally, the nighttime peak in weekdays (21:00 p.m.) is one hour later than weekends (20:00 p.m.) which also shows the evidence of human activity. These observed facts indicate that the variations of PM2.5 concentration between urban and suburban areas in Beijing are influenced by complex meteorological factors and human activities. PMID:26426035

  20. Accumulation and distribution characteristics of platinum group elements in roadside dusts in Beijing, China.

    PubMed

    Gao, Bo; Yu, Yanke; Zhou, Huaidong; Lu, Jin

    2012-06-01

    The concentrations, distribution, and accumulation of platinum group elements (PGEs) were investigated in roadside dusts collected in four different foundational areas in Beijing during February to May 2010. The results showed that PGE levels in all samples were above the average upper crust values, with mean concentrations of 57.5 ng · g(-1) Pd, 28.2 ng · g(-1) Pt, and 9.8 ng · g(-1) Rh, respectively. Palladium concentration has increased rapidly in recent years. The rank of PGE levels in four different functional regions for roadside dusts was: heavy density traffic area > residential area > educational area > tourism area. Palladium, Pt, and Rh concentrations in dusts showed strong positive correlations, indicating a common traffic-related source of these metals. Meanwhile, PGEs in these samples were not correlated with other traffic-related metals except for Cr. The average PGE ratios of road dusts from Beijing were consistent with those in Germany and Western Australia, but lower than those in the United States and Mexico, indicating that various catalyst productions were used in different countries. In addition, grain-size partitioning of PGEs in dusts indicated that concentrations of PGEs differed from one particle size to another. The coarse fraction had higher PGE concentrations than the fine fraction in roadside dusts. These results showed that autocatalyst PGE contamination estimates in the environment would be significantly underestimated if only a fine-grain size fraction (<0.063 mm) is analyzed. PMID:22505271

  1. 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

  2. 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

  3. Monitoring land subsidence rates with permanent scatterers SAR interferometry: a case study of Beijing, China

    NASA Astrophysics Data System (ADS)

    Fan, Jun; Li, Xiaojuan; Yu, Jie; Wang, Yanbing; Wan, Yanyan; An, Zhihui

    2015-12-01

    The ground subsidence phenomenon is more serious in Beijing, large-scale land subsidence seriously threats to urban planning and construction and the safety of residents. In order to study the subsidence condition, it is necessary to monitor land subsidence. Choosing 28 scenes Envisat ASAR images covering Beijing city from December 2003 to March 2009, permanent scatterer SAR interferometry (PSI) technique was applied to obtained time series land subsidence information. Then the trend characteristics and factors of subsidence were analyzed, comparing land subsidence result with the groundwater data and geological structure data. Comparison between the PSI-derived subsidence rates and leveling data obtained shows that the result of PSI is agreed with the leveling data. The results indicate that the PSI technique is capable of providing high-level accuracy subsidence information. The results show that:(1) The deformation rates derived PSI ranging from -45.80 to 4.36mm/a;(2) In the study area, the serious subsidence areas distribute in Chaoyang District, Shunyi District, Tongzhou District and Pinggu District;(3) The subsidence tends to become more and more concentrated in 6 years from 2003 to 2009.

  4. Characterizing ozone pollution in a petrochemical industrial area in Beijing, China: a case study using a chemical reaction model.

    PubMed

    Wei, Wei; Lv, Zhaofeng; Cheng, Shuiyuan; Wang, Lili; Ji, Dongsheng; Zhou, Ying; Han, Lihui; Wang, Litao

    2015-06-01

    This study selected a petrochemical industrial complex in Beijing, China, to understand the characteristics of surface ozone (O3) in this industrial area through the on-site measurement campaign during the July-August of 2010 and 2011, and to reveal the response of local O3 to its precursors' emissions through the NCAR-Master Mechanism model (NCAR-MM) simulation. Measurement results showed that the O3 concentration in this industrial area was significantly higher, with the mean daily average of 124.6 μg/m(3) and mean daily maximum of 236.8 μg/m(3), which are, respectively, 90.9 and 50.6 % higher than those in Beijing urban area. Moreover, the diurnal O3 peak generally started up early in 11:00-12:00 and usually remained for 5-6 h, greatly different with the normal diurnal pattern of urban O3. Then, we used NCAR-MM to simulate the average diurnal variation of photochemical O3 in sunny days of August 2010 in both industrial and urban areas. A good agreement in O3 diurnal variation pattern and in O3 relative level was obtained for both areas. For example of O3 daily maximum, the calculated value in the industrial area was about 51 % higher than in the urban area, while measured value in the industrial area was approximately 60 % higher than in the urban area. Finally, the sensitivity analysis of photochemical O3 to its precursors was conducted based on a set of VOCs/NOx emissions cases. Simulation results implied that in the industrial area, the response of O3 to VOCs was negative and to NOx was positive under the current conditions, with the sensitivity coefficients of -0.16~-0.43 and +0.04~+0.06, respectively. By contrast, the urban area was within the VOCs-limitation regime, where ozone enhancement in response to increasing VOCs emissions and to decreasing NOx emission. So, we think that the VOCs emissions control for this petrochemical industrial complex will increase the potential risk of local ozone pollution aggravation, but will be helpful to inhibit the

  5. Particle hygroscopicity and its link to chemical composition in the urban atmosphere of Beijing, China during summertime

    NASA Astrophysics Data System (ADS)

    Wu, Z. J.; Zheng, J.; Shang, D. J.; Du, Z. F.; Wu, Y. S.; Zeng, L. M.; Wiedensohler, A.; Hu, M.

    2015-04-01

    Simultaneous measurements of particle number size distribution, particle hygroscopic properties, and size-resolved chemical composition were made during the summer of 2014 in Beijing, China. During the measurement period, the median hygroscopicity parameters (κ) of 50, 100, 150, 200, and 250 nm particles are respectively 0.15, 0.19, 0.22, 0.27, and 0.29, showing an increasing trend with increasing particle size. When PM2.5 mass concentration is greater than 50 μg m-3, the fractions of the hydrophilic mode for 150, 250, 350 nm particles increased towards 1 as PM2.5 mass concentration increased. This indicates that aged particles dominated during severe pollution periods in the atmosphere of Beijing. Particle hygroscopic growth can be well predicted using high time-resolution size-resolved chemical composition derived from AMS measurement on a basis of ZSR mixing rule. An empirical relationship between κ of organic fraction (κorg) and oxygen to carbon ratio (O : C) (κorg= 0.08·O : C+0.02) is obtained. During new particle formation event associating with strongly active photochemistry, the hygroscopic growth factor or κ of newly formed particles is greater than for particle with the same sizes during non-NPF periods. A quick transformation from external mixture to internal mixture for pre-existing particles (for example 250 nm particle) was observed. Such transformations can modify the state of mixture of pre-exiting particles and thus modify properties such as the light absorption coefficient and cloud condensation nuclei activation.

  6. Particle hygroscopicity and its link to chemical composition in the urban atmosphere of Beijing, China, during summertime

    NASA Astrophysics Data System (ADS)

    Wu, Z. J.; Zheng, J.; Shang, D. J.; Du, Z. F.; Wu, Y. S.; Zeng, L. M.; Wiedensohler, A.; Hu, M.

    2016-02-01

    Simultaneous measurements of particle number size distribution, particle hygroscopic properties, and size-resolved chemical composition were made during the summer of 2014 in Beijing, China. During the measurement period, the mean hygroscopicity parameters (κs) of 50, 100, 150, 200, and 250 nm particles were respectively 0.16 ± 0.07, 0.19 ± 0.06, 0.22 ± 0.06, 0.26 ± 0.07, and 0.28 ± 0.10, showing an increasing trend with increasing particle size. Such size dependency of particle hygroscopicity was similar to that of the inorganic mass fraction in PM1. The hydrophilic mode (hygroscopic growth factor, HGF > 1.2) was more prominent in growth factor probability density distributions and its dominance of hydrophilic mode became more pronounced with increasing particle size. When PM2.5 mass concentration was greater than 50 μg m-3, the fractions of the hydrophilic mode for 150, 250, and 350 nm particles increased towards 1 as PM2.5 mass concentration increased. This indicates that aged particles dominated during severe pollution periods in the atmosphere of Beijing. Particle hygroscopic growth can be well predicted using high-time-resolution size-resolved chemical composition derived from aerosol mass spectrometer (AMS) measurements using the Zdanovskii-Stokes-Robinson (ZSR) mixing rule. The organic hygroscopicity parameter (κorg) showed a positive correlation with the oxygen to carbon ratio. During the new particle formation event associated with strongly active photochemistry, the hygroscopic growth factor or κ of newly formed particles is greater than for particles with the same sizes not during new particle formation (NPF) periods. A quick transformation from external mixture to internal mixture for pre-existing particles (for example, 250 nm particles) was observed. Such transformations may modify the state of the mixture of pre-existing particles and thus modify properties such as the light absorption coefficient and cloud condensation nuclei activation.

  7. Chemical composition of aerosol particles and light extinction apportionment before and during the heating season in Beijing, China

    NASA Astrophysics Data System (ADS)

    Wang, Qingqing; Sun, Yele; Jiang, Qi; Du, Wei; Sun, Chengzhu; Fu, Pingqing; Wang, Zifa

    2015-12-01

    Despite extensive efforts into characterization of the sources and formation mechanisms of severe haze pollution in the megacity of Beijing, the response of aerosol composition and optical properties to coal combustion emissions in the heating season remain poorly understood. Here we conducted a 3 month real-time measurement of submicron aerosol (PM1) composition by an Aerosol Chemical Speciation Monitor and particle light extinction by a Cavity Attenuated Phase Shift extinction monitor in Beijing, China, from 1 October to 31 December 2012. The average (±σ) PM1 concentration was 82.4 (±73.1) µg/m3 during the heating period (HP, 15 November to 31 December), which was nearly 50% higher than that before HP (1 October to 14 November). While nitrate and secondary organic aerosol (SOA) showed relatively small changes, organics, sulfate, and chloride were observed to have significant increases during HP, indicating the dominant impacts of coal combustion sources on these three species. The relative humidity-dependent composition further illustrated an important role of aqueous-phase processing for the sulfate enhancement during HP. We also observed great increases of hydrocarbon-like OA (HOA) and coal combustion OA (CCOA) during HP, which was attributed to higher emissions at lower temperatures and coal combustion emissions, respectively. The relationship between light extinction and chemical composition was investigated using a multiple linear regression model. Our results showed that the largest contributors to particle extinction were ammonium nitrate (32%) and ammonium sulfate (28%) before and during HP, respectively. In addition, the contributions of SOA and primary OA to particle light extinction were quantified. The results showed that the OA extinction was mainly caused by SOA before HP and by SOA and CCOA during HP, yet with small contributions from HOA and cooking aerosol for the entire study period. Our results elucidate substantial changes of aerosol

  8. Effect of Traffic Exposure on Sick Building Syndrome Symptoms among Parents/Grandparents of Preschool Children in Beijing, China

    PubMed Central

    Li, Linyan; Adamkiewicz, Gary; Zhang, Yinping; Spengler, John D.; Qu, Fang; Sundell, Jan

    2015-01-01

    Introduction Sick building syndrome (SBS) includes general, mucosal and skin symptoms. It is typically associated with an individual's place of work or residence. The aim of this study was to explore the effect of traffic exposure on SBS symptoms in Beijing, China. Methods From January to May, 2011, recruitment occurred at kindergartens in 11 districts in Beijing. Self-administered questionnaires were distributed by teachers to legal guardians of children and then returned to teachers. The questionnaire asked them to recall the presence of 12 SBS symptoms from the previous three months. Living near a highway or main road (within 200 meters) was used as a proxy for traffic exposure. Multivariable logistic regression was used to test the association between traffic exposure and a higher number of SBS symptoms, controlling for key covariates. Results There were 5487 valid questionnaires (65.0% response rate). Univariate analysis showed that living near a main road or highway (OR = 1.40), female gender (OR = 1.44), and environmental tobacco smoking (ETS) (OR = 1.13) were significant risk factors for general symptoms. Grandparent’s generation (OR = 0.32) and home ownership (owner vs. renter) (OR = 0.89) were significant protective factors. The adjusted odds ratio (aOR) for the association between living close to a highway and general symptoms remained significant in the multivariable model (aOR = 1.39; 95% CI = 1.21: 1.59). ORs and aORs were similar for mucosal and skin symptoms. Conclusions This study found traffic exposure to be significantly associated with SBS symptoms. This finding is consistent with current literature that indicates an association between adverse health effects and living near highway or main road. PMID:26086248

  9. Monetary Valuation of PM10-Related Health Risks in Beijing China: The Necessity for PM10 Pollution Indemnity

    PubMed Central

    Yin, Hao; Xu, Linyu; Cai, Yanpeng

    2015-01-01

    Severe health risks caused by PM10 (particulate matter with an aerodynamic diameter ≤10 μm) pollution have induced inevitable economic losses and have rendered pressure on the sustainable development of society as a whole. In China, with the “Polluters Pay Principle”, polluters should pay for the pollution they have caused, but how much they should pay remains an intractable problem for policy makers. This paper integrated an epidemiological exposure-response model with economics methods, including the Amended Human Capital (AHC) approach and the Cost of Illness (COI) method, to value the economic loss of PM10-related health risks in 16 districts and also 4 functional zones in Beijing from 2008 to 2012. The results show that from 2008 to 2012 the estimated annual deaths caused by PM10 in Beijing are around 56,000, 58,000, 63,000, 61,000 and 59,000, respectively, while the economic losses related to health damage increased from around 23 to 31 billion dollars that PM10 polluters should pay for pollution victims between 2008 and 2012. It is illustrated that not only PM10 concentration but also many other social economic factors influence PM10-related health economic losses, which makes health economic losses show a time lag discrepancy compared with the decline of PM10 concentration. In conclusion, health economic loss evaluation is imperative in the pollution indemnity system establishment and should be considered for the urban planning and policy making to control the burgeoning PM10 health economic loss. PMID:26308020

  10. Monetary Valuation of PM10-Related Health Risks in Beijing China: The Necessity for PM10 Pollution Indemnity.

    PubMed

    Yin, Hao; Xu, Linyu; Cai, Yanpeng

    2015-08-01

    Severe health risks caused by PM10 (particulate matter with an aerodynamic diameter ≤10 μm) pollution have induced inevitable economic losses and have rendered pressure on the sustainable development of society as a whole. In China, with the "Polluters Pay Principle", polluters should pay for the pollution they have caused, but how much they should pay remains an intractable problem for policy makers. This paper integrated an epidemiological exposure-response model with economics methods, including the Amended Human Capital (AHC) approach and the Cost of Illness (COI) method, to value the economic loss of PM10-related health risks in 16 districts and also 4 functional zones in Beijing from 2008 to 2012. The results show that from 2008 to 2012 the estimated annual deaths caused by PM10 in Beijing are around 56,000, 58,000, 63,000, 61,000 and 59,000, respectively, while the economic losses related to health damage increased from around 23 to 31 billion dollars that PM10 polluters should pay for pollution victims between 2008 and 2012. It is illustrated that not only PM10 concentration but also many other social economic factors influence PM10-related health economic losses, which makes health economic losses show a time lag discrepancy compared with the decline of PM10 concentration. In conclusion, health economic loss evaluation is imperative in the pollution indemnity system establishment and should be considered for the urban planning and policy making to control the burgeoning PM10 health economic loss. PMID:26308020

  11. On the Main Factors Controlling Anthropogenic Land Subsidence in the Northern Plain of the Chaobai River, North Beijing, China

    NASA Astrophysics Data System (ADS)

    Zhu, L.; Teatini, P.; Gong, H.; Ke, Y.; Pan, Y.

    2014-12-01

    Anthropogenic land subsidence is a widespread phenomenon threatening several cities in China. One major area of land subsidence is the Beijing city. The city continues to grow and unofficial estimates put the population at around 21-22 million in 2013, with an increase by 40% from 2000 to 2010. Along with the increasing urbanization, demands for water resources become larger. Approximately 2/3 of the water need is supplied by groundwater. To cope with the pressure for water supply, a first "over-sized emergency groundwater resource region (EGRR)" was built in 2003 at the Huairou district, where is the upper and middle plain of the Chaobai River, few tens km to the north of the metropolitan center. Other four EGRRwell-fields have been established in different districts surrounding the city in the next years. The long-time over-exploitation of groundwater resulted in water level fall and land subsidence. Persistent Scatterer Interferometry (PSI) on ENVISAT images has been used to detect land subsidence in the northern Beijing plain from 2003 to 2010. The PSI outcome, which was calibrated using ground-based measurements including levelling and extensometers, reveals that the largest subsidence rate reached 52 mm/yr, with a cumulative maximum sinking equal to 342 mm, in the Houshayu city at the southwestern part of the study area where the capital international airport is situated. Land subsidence in the northern zones, where the main well-fields are located, was much smaller in the order of 60 mm. Hydro-geologic investigations have showed that the distribution of groundwater depression cones only partially resembles the land subsidence pattern. The subsidence rates are strongly correlated with the distribution of compressible clay units. In the south-westernmost zone, at the bound of the metropolitan area, the cumulative thickness of cohesive soils amounts to 250 m in the upper 390 m sedimentary sequence. Conversely, sands and gravels prevail in the northern portion

  12. Efficiency of Primary Schools in Beijing, China: An Evaluation by Data Envelopment Analysis

    ERIC Educational Resources Information Center

    Hu, Yongmei; Zhang, Zhi; Liang, Wenyan

    2009-01-01

    Purpose: Under the new policy framework, the China Government will substantially increase education resources investment. As a result, financial under-provision of schools will not be the main problem in the near future. However, school efficiency will emerge as the new factor in attracting the attention of the government and the public in China,…

  13. From the Vantage of the Beijing Hotel: Peering into the 1989 Student Unrest in China.

    ERIC Educational Resources Information Center

    Hsiung, James C.

    1990-01-01

    Provides an eyewitness account of the 1989 Tiananmen Square conflict in China. Discusses the discrepancies between outside reports on the conflict and the official video of the government. Analyzes the events of the conflict and outlines mistakes of the tragedy. Suggests actions that need to be taken by China. (RW)

  14. An air quality forecasting system in Beijing--application to the study of dust storm events in China in May 2008.

    PubMed

    Zhang, Qijie; Laurent, Benoit; Velay-Lasry, Fanny; Ngo, Richard; Derognat, Claude; Marticorena, Béatrice; Albergel, Armand

    2012-01-01

    An air pollution forecast system, ARIA Regional, was implemented in 2007-2008 at the Beijing Municipality Environmental Monitoring Center, providing daily forecast of main pollutant concentrations. The chemistry-transport model CHIMERE was coupled with the dust emission model MB95 for restituting dust storm events in springtime so as to improve forecast results. Dust storm events were sporadic but could be extremely intense and then control air quality indexes close to the source areas but also far in the Beijing area. A dust episode having occurred at the end of May 2008 was analyzed in this article, and its impact of particulate matter on the Chinese air pollution index (API) was evaluated. Following our estimation, about 23 Tg of dust were emitted from source areas in Mongolia and in the Inner Mongolia of China, transporting towards southeast. This episode of dust storm influenced a large part of North China and East China, and also South Korea. The model result was then evaluated using satellite observations and in situ data. The simulated daily concentrations of total suspended particulate at 6:00 UTC had a similar spatial pattern with respect to OMI satellite aerosol index. Temporal evolution of dust plume was evaluated by comparing dust aerosol optical depth (AOD) calculated from the simulations with AOD derived from MODIS satellite products. Finally, the comparison of reported Chinese API in Beijing with API calculated from the simulation including dust emissions had showed the significant improvement of the model results taking into account mineral dust correctly. PMID:22783620

  15. Hepatitis C Virus Subtype and Evolution Characteristic Among Drug Users, Men Who Have Sex With Men, and the General Population in Beijing, China.

    PubMed

    Jiao, Yang; Zhang, Xiaoxi; Wang, Chen; Li, Li; Liu, Jie; Bar, Katharine J; Wei, Huamian; Hu, Yao; Huang, Ping; Zeng, Zhaoli; Jiang, Shulin; Du, Jialiang; Shao, Yiming; Metzger, David; Li, Shuming; Ma, Liying

    2016-02-01

    The aim of this study was to characterize the current molecular epidemiology of hepatitis C virus (HCV) infection and evaluate the evolutionary patterns of HCV subtypes in Beijing, China, among different subpopulations.The whole blood samples and behavioral data were collected from a total of 10,354 subjects, including drug users (DUs), men who have sex with men (MSM), and the general population, in Beijing from 2010 to 2011. Samples were tested for HCV infection using both enzyme-linked immunosorbent assay (ELISA) and real-time PCR. All viremic subjects were then sequenced by nested PCR over core/E1 and NS5B regions. Phylogenetic and phylogeographic analysis was performed by BEAST software.In total, 217 subjects (2.1%) were tested positive for HCV by antibody or vRNA-based testing. HCV prevalence rates for DUs, MSM, and the general population were 26.2%, 0.54%, and 0.37%, respectively. The 156 HCV RNA-positive samples were sequenced. Nine HCV genotypes, including 1a, 1b, 2a, 3a, 3b, 6a, 6n, 6u and 6v, were detected. The most prevalent subtypes were 3b (36.09%), 1b (32.54%), and 3a (16.57%). Bayesian evolutionary analysis estimated that the time of introduction of subtype 1b into Beijing was 2004 (95% CI: 1997.7, 2007.7), with subtypes 3a and 3b being introduced later in 2006. Evolutionary analyses further suggested that subtype 1b from Beijing and Shanghai were closely related, whereas subtype 3a sequences were more similar with sequences from Yunnan, Guangzhou, Hong Kong, and Jiangsu. Subtype 3b sequences were closely related to those from Yunnan, Guangdong, and Hong Kong.Thus, the current HCV epidemic in Beijing is complex, heavily affecting DUs, and involving multiple genotypes that likely spread from different regions in China with its large migrant population. PMID:26871798

  16. Hepatitis C Virus Subtype and Evolution Characteristic Among Drug Users, Men Who Have Sex With Men, and the General Population in Beijing, China

    PubMed Central

    Jiao, Yang; Zhang, Xiaoxi; Wang, Chen; Li, Li; Liu, Jie; Bar, Katharine J.; Wei, Huamian; Hu, Yao; Huang, Ping; Zeng, Zhaoli; Jiang, Shulin; Du, Jialiang; Shao, Yiming; Metzger, David; Li, Shuming; Ma, Liying

    2016-01-01

    Abstract The aim of this study was to characterize the current molecular epidemiology of hepatitis C virus (HCV) infection and evaluate the evolutionary patterns of HCV subtypes in Beijing, China, among different subpopulations. The whole blood samples and behavioral data were collected from a total of 10,354 subjects, including drug users (DUs), men who have sex with men (MSM), and the general population, in Beijing from 2010 to 2011. Samples were tested for HCV infection using both enzyme-linked immunosorbent assay (ELISA) and real-time PCR. All viremic subjects were then sequenced by nested PCR over core/E1 and NS5B regions. Phylogenetic and phylogeographic analysis was performed by BEAST software. In total, 217 subjects (2.1%) were tested positive for HCV by antibody or vRNA-based testing. HCV prevalence rates for DUs, MSM, and the general population were 26.2%, 0.54%, and 0.37%, respectively. The 156 HCV RNA-positive samples were sequenced. Nine HCV genotypes, including 1a, 1b, 2a, 3a, 3b, 6a, 6n, 6u and 6v, were detected. The most prevalent subtypes were 3b (36.09%), 1b (32.54%), and 3a (16.57%). Bayesian evolutionary analysis estimated that the time of introduction of subtype 1b into Beijing was 2004 (95% CI: 1997.7, 2007.7), with subtypes 3a and 3b being introduced later in 2006. Evolutionary analyses further suggested that subtype 1b from Beijing and Shanghai were closely related, whereas subtype 3a sequences were more similar with sequences from Yunnan, Guangzhou, Hong Kong, and Jiangsu. Subtype 3b sequences were closely related to those from Yunnan, Guangdong, and Hong Kong. Thus, the current HCV epidemic in Beijing is complex, heavily affecting DUs, and involving multiple genotypes that likely spread from different regions in China with its large migrant population. PMID:26871798

  17. Basic Graduate Curricula of GIS Design in Beijing Normal University, China

    NASA Astrophysics Data System (ADS)

    Liu, H.

    2015-05-01

    As the basic course of postgraduate programme in Beijing Normal University, the Introduction of GIS&T is selected by almost all the students of the GIS specialty and other related specialties like physical and human geography, ecology, environmental science and so on. The number of the students dropped in the course was over 100 each year in the past 5 years. The background of education and demands of the students were very different. How to design the course of Introduction of GIS&T to meet the demands of students is important. This paper include following parts: (1) The analysis of student's difference and the structure design of the course, (2) Spatial thinking and the body of knowledge design, (3) The practice exercises design, and (4) Feedback and evaluating.

  18. Characterization of new particle and secondary aerosol formation during summertime in Beijing, China

    NASA Astrophysics Data System (ADS)

    Zhang, Y. M.; Zhang, X. Y.; Sun, J. Y.; Lin, W. L.; Gong, S. L.; Shen, X. J.; Yang, S.

    2011-07-01

    Size-resolved aerosol number and mass concentrations and the mixing ratios of O3 and various trace gases were continuously measured at an urban station before and during the Beijing Olympic and Paralympic Games (5 June to 22 September, 2008). 23 new particle formation (NPF) events were identified; these usually were associated with changes in wind direction and/or rising concentrations of gas-phase precursors or after precipitation events. Most of the NPF events started in the morning and continued to noon as particles in the nucleation mode grew into the Aitken mode. From noon to midnight, the aerosols grew into the accumulation mode through condensation and coagulation. Ozone showed a gradual rise starting around 10:00 local time, reached its peak around 15:00 and then declined as the organics increased. The dominant new particle species were organics (40-75% of PM1) and sulphate; nitrate and ammonium were more minor contributors.

  19. Temporal variation of trace compound emission on the working surface of a landfill in Beijing, China

    NASA Astrophysics Data System (ADS)

    Duan, Zhenhan; Lu, Wenjing; Li, Dong; Wang, Hongtao

    2014-05-01

    The temporal variation of trace component emissions from the working surface of a landfill in Beijing was investigated. Specific days in a year were selected as representatives for all four seasons. Different chemical species were quantified in all four seasons with the following average concentrations: spring: 41 compounds, 2482.6 μg m-3; summer: 59 compounds, 4512.6 μg m-3; fall: 66 compounds, 2438.4 μg m-3; and winter: 54 compounds, 2901 μg m-3. The detected compounds included sulfur compounds, oxygenated compounds, aromatics, hydrocarbons, halogenated compounds, and terpenes. Oxygenated compounds were the most abundant compound in most samples. Isobutane, ethyl alcohol, limonene, butane, toluene, and trichlorofluoromethane were recognized as the most abundant compounds on the working surface throughout the year. This study would bring new light in assessing the particle pollution in urban areas and the effect of trace components on landfill odor.

  20. Mixing layer height and its implications for air pollution over Beijing, China

    NASA Astrophysics Data System (ADS)

    Tang, Guiqian; Zhang, Jinqiang; Zhu, Xiaowan; Song, Tao; Münkel, Christoph; Hu, Bo; Schäfer, Klaus; Liu, Zirui; Zhang, Junke; Wang, Lili; Xin, Jinyuan; Suppan, Peter; Wang, Yuesi

    2016-03-01

    The mixing layer is an important meteorological factor that affects air pollution. In this study, the atmospheric mixing layer height (MLH) was observed in Beijing from July 2009 to December 2012 using a ceilometer. By comparison with radiosonde data, we found that the ceilometer underestimates the MLH under conditions of neutral stratification caused by strong winds, whereas it overestimates the MLH when sand-dust is crossing. Using meteorological, PM2.5, and PM10 observational data, we screened the observed MLH automatically; the ceilometer observations were fairly consistent with the radiosondes, with a correlation coefficient greater than 0.9. Further analysis indicated that the MLH is low in autumn and winter and high in spring and summer in Beijing. There is a significant correlation between the sensible heat flux and MLH, and the diurnal cycle of the MLH in summer is also affected by the circulation of mountainous plain winds. Using visibility as an index to classify the degree of air pollution, we found that the variation in the sensible heat and buoyancy term in turbulent kinetic energy (TKE) is insignificant when visibility decreases from 10 to 5 km, but the reduction of shear term in TKE is near 70 %. When visibility decreases from 5 to 1 km, the variation of the shear term in TKE is insignificant, but the decrease in the sensible heat and buoyancy term in TKE is approximately 60 %. Although the correlation between the daily variation of the MLH and visibility is very poor, the correlation between them is significantly enhanced when the relative humidity increases beyond 80 %. This indicates that humidity-related physicochemical processes is the primary source of atmospheric particles under heavy pollution and that the dissipation of atmospheric particles mainly depends on the MLH. The presented results of the atmospheric mixing layer provide useful empirical information for improving meteorological and atmospheric chemistry models and the forecasting

  1. Mixing ratio and carbon isotopic composition investigation of atmospheric CO2 in Beijing, China.

    PubMed

    Pang, Jiaping; Wen, Xuefa; Sun, Xiaomin

    2016-01-01

    The stable isotope composition of atmospheric CO2 can be used as a tracer in the study of urban carbon cycles, which are affected by anthropogenic and biogenic CO2 components. Continuous measurements of the mixing ratio and δ(13)C of atmospheric CO2 were conducted in Beijing from Nov. 15, 2012 to Mar. 8, 2014 including two heating seasons and a vegetative season. Both δ(13)C and the isotopic composition of source CO2 (δ(13)CS) were depleted in the heating seasons and enriched in the vegetative season. The diurnal variations in the CO2 mixing ratio and δ(13)C contained two peaks in the heating season, which are due to the effects of morning rush hour traffic. Seasonal and diurnal patterns of the CO2 mixing ratio and δ(13)C were affected by anthropogenic emissions and biogenic activity. Assuming that the primary CO2 sources at night (22:00-04:00) were coal and natural gas combustion during heating seasons I and II, an isotopic mass balance analysis indicated that coal combustion had average contributions of 83.83±14.11% and 86.84±12.27% and that natural gas had average contributions of 16.17±14.11% and 13.16±12.27%, respectively. The δ(13)C of background CO2 in air was the main error source in the isotopic mass balance model. Both the mixing ratio and δ(13)C of atmospheric CO2 had significant linear relationships with the air quality index (AQI) and can be used to indicate local air pollution conditions. Energy structure optimization, for example, reducing coal consumption, will improve the local air conditions in Beijing. PMID:26363727

  2. Characterization of submicron particles during biomass burning and coal combustion periods in Beijing, China.

    PubMed

    Zhang, J K; Cheng, M T; Ji, D S; Liu, Z R; Hu, B; Sun, Y; Wang, Y S

    2016-08-15

    An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was deployed along with other observation instruments to measure the characteristics of PM1 (particulate matter with a vacuum aerodynamic diameter of ≤1μm) during the biomass burning period (October 1 to 27; BBP) and the coal combustion period (December 10 to 31; CCP) in Beijing in 2014. The average PM1 mass concentrations during the BBP and CCP were 82.3 and 37.5μgm(-3), respectively. Nitrate, ammonium and other pollutants emitted by the burning processes, especially coal combustion, increased significantly in association with increased pollution levels. Positive matrix factorization (PMF) was applied to a unified high-resolution mass spectra database of organic species with NO(+) and NO2(+) ions to discover the relationships between organic and inorganic species. One inorganic factor was identified in both periods, and another five and four distinct organic factors were identified in the BBP and CCP, respectively. Secondary organic aerosols (SOAs) accounted for 55% of the total organic aerosols (OAs) during the BBP, which is higher than the proportion during the CCP (oxygenated OA, 40%). The organic nitrate and inorganic nitrate were first successfully separated through the PMF analysis based on the HR-ToF-AMS observations in Beijing, and organic nitrate components accounted for 21% and 18% of the total nitrate mass during the BBP and CCP, respectively. Although the PM1 mass concentration during the CCP was much lower than in the BBP, the average concentration of polycyclic aromatic hydrocarbons (PAHs) during the CCP (107.3±171.6ngm(-3)) was ~5 times higher than that in the BBP (21.9±21.7ngm(-3)). PMID:27110992

  3. [Situation and Characteristics of Air Pollutants Emission from Crematories in Beijing, China].

    PubMed

    Xue, Yi-feng; Yan, Jing; Tian, He-zhong; Xiong, Cheng-cheng; Li, Jing-dong; Wu, Xiao-ing; Wang, Wei

    2015-06-01

    Hazardous Air Pollutants (HAPs) such as exhaust particulate matter (PM), carbon monoxide (CO), sulfur dioxide (SO2), nitrogen oxide (NOx), mercury (Hg) and polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-furans ( PCDD/Fs) are emitted by the process of cremation and the burning of oblation. Risks to health posed by emissions of hazardous air pollutants from crematories are emerging concerns. Through field investigation and data collection, we obtained the related activity levels and monitored the concentrations of air pollutants from typical cremators, so as to better understand the current pollutants emission levels for crematory. Using the emission factor method, we calculated the emission inventory of HAPs for crematory of Beijing in 2012 and quantified the range of uncertainty. Using atmospheric diffusion model ADMS, we evaluated the influence of crematories on the surrounding environment, and identified the characteristics of air pollution. The results showed that: for the cremators installed with flue gas purification system, the emission concentration of exhaust PM was rather low, and the CO emission concentration fluctuated greatly. However, relative high emission concentrations of PCDD/Fs were detected mainly due to insufficient combustion. Exhaust PM, CO, SO2, NOx, Hg and PCDD/Fs emitted by crematory of Beijing in 2012 were estimated at about 11. 5 tons, 41.25 tons, 2.34 tons, 7.65 tons, 13.76 kg and 0.88 g, respectively; According to the results of dispersion model simulation, the concentration contributions of exhaust PM, CO, SO2, NOx, Hg, PCDD/Fs from crematories were 0.05947 microg x m(-3), 0.2009 microg x m(-3) and 0.0126 microg x m(-3), 0.03667 microg x m(-3) and 0.06247 microg x m(-3), 0.004213 microg x m(-3), respectively. PMID:26387295

  4. Mixing layer height and the implications for air pollution over Beijing, China

    NASA Astrophysics Data System (ADS)

    Tang, G.; Zhang, J.; Münkel, C.; Song, T.; Hu, B.; Schäfer, K.; Liu, Z.; Xin, J.; Suppan, P.; Wang, Y.

    2015-10-01

    The mixing layer is an important meteorological factor that affects atmospheric pollution. A study of atmospheric pollution in the Beijing area was performed from July 2009 to December 2012, using a ceilometer, to observe and study the atmospheric mixing layer height (MLH). Based on a comparison and validation of multiple types of data, we evaluated the quality of the MLH data as observed by the ceilometer and found that the ceilometer underestimates MLH during neutral stratification caused by strong winds, whereas it overestimates MLH during dust crossing. By combining conventional meteorological data and PM2.5 and PM10 observational data, we screened the observational results for the MLH, and the ceilometer observations were fairly consistent with the meteorological radiosonde profile results. The correlation coefficient is more than 0.9, and the effective rate of acquired data is near 80 %. Further analysis of the variation in the MLH indicates that the MLH in the Beijing area exhibits the feature of being low in autumn and winter and being high in spring and summer. There is a significant correlation between the variation in the MLH and the sensible heat flux, whereas the diurnal variation in the mixing layer during summer is affected by the circulation of mountainous plain winds. By applying visibility as the index for the classification of atmospheric pollution degree, it is found that in comparison with a clear day, the variation of sensible heat and buoyancy term in turbulent kinetic energy (TKE) of a slight haze day is insignificant, but the reduction of shear term in TKE is near 70 % when visibility decreased from 10 to 5 km; in comparison with the slight haze day, the variation of shear term in TKE of medium and heavy haze days is insignificant, but the declination of sensible heat and buoyancy term in TKE are about 60 % when visibility decreased from 5 to 1 km. Although the correlation between the daily variation of MLH and visibility is very poor, the

  5. The roles of organics in New particle formation in the Megacity of Beijing, China

    NASA Astrophysics Data System (ADS)

    Hu, Min; Wang, Zhibin; Wu, Zhijun; Yue, Dingli; Zheng, Jun; Zhang, Renyi; Boy, Michael; Wiedensohler, Alfred

    2013-04-01

    The new particle formation (NPF) has been investigated in the high aerosol loading environment of Beijing since March 2004. The occurrence frequency is comparable with less aerosol loading environment, whereas the monthly or seasonal variations indicate location dependency. Simultaneously measurements of gaseous precursors of H2SO4 vapor and ammonia proved that the H2SO4-NH3-H2O ternary nucleation is an important mechanism for Beijing NPF, which is mainly constrained by the concentrations of the gaseous sulfuric acid and total particle surface area. The higher particle formation rates were observed on high aerosol loading days, followed up NPF, then high organic matter observed by AMS, which indicated the organic vapors should be involved in the new particle formation process. The roles of organics in the formation and growth of the NPF were focused on in the case of summer 2008, Olympic Games period, the particle formation rates show good correlations with sulfuric acid and organic vapors implying that both play an important role in the atmospheric new particle formation. The best fit between observed and modelled particle formation rates is achieved with the homogenous nucleation theory of sulfuric acid (both homomolecularly and hetermolecularly) with separate coefficients in J = KSA1[H2SO4]2 + KSA2[H2SO4][Org], in which the contributions of the sulfuric acid and the organics involving terms have been estimated as 43% and 57%, respectively. The growth of new particles contributed by condensation and neutralization of sulfuric acid, coagulation as well as organic compounds involved growth are discussed. The apparent growth rates vary from 3 to 11 nm h-1. Condensation of sulfuric acid and its subsequent neutralization by ammonia and coagulation contribute to the apparent particle growth on average 45±18% and 34±17%, respectively. The 30% higher concentration of sulfate than organic compounds in particles during the sulfur-rich NPF events but 20% lower

  6. Detection, occurrence and fate of 22 psychiatric pharmaceuticals in psychiatric hospital and municipal wastewater treatment plants in Beijing, China.

    PubMed

    Yuan, Shengliu; Jiang, Xiaoman; Xia, Xinghui; Zhang, Haixia; Zheng, Shaokui

    2013-03-01

    The liquid chromatography-electrospray ionization-tandem mass spectrometer (LC-MS/MS) method coupled with an automated solid-phase extraction procedure has been developed to identify 22 psychiatric pharmaceuticals, including seven anxiolytic-sedative-hypnotics, six antidepressants, and nine anti-schizophrenia drugs, in wastewater samples from two psychiatric hospital wastewater treatment plants (P-WWTPs) and three municipal wastewater treatment plants (M-WWTPs) in Beijing, China. Analyte recoveries from spiking experiments in the WWTP influent and effluent at three concentrations ranged from 70% to 110%, excluding sulpiride, ziprasidone, and olanzapine. Method detection limits for five, eight, and nine analytes in the WWTP influent and effluent were 20-80, 1-16, and <1 ng L(-1), respectively. High psychiatric pharmaceutical concentrations (e.g., ∼942 ng L(-1) oxazepam, 5552-12,782 ng L(-1) clozapine, 2762-9832 ng L(-1) sulpiride, and 2030-4967 ng L(-1) quetiapine) were frequently observed in P-WWTP influent compared to M-WWTPs. Although P-WWTPs typically had higher removal rates, significantly higher concentrations of the target compounds were observed in the P-WWTP secondary effluent than in the M-WWTP influent (e.g., ∼752 ng L(-1) oxazepam, ∼8183 ng L(-1) clozapine, ∼10,833 ng L(-1) sulpiride, and ∼1168 ng L(-1) quetiapine). Thus, the discharge control of psychiatric pharmaceuticals from psychiatric hospitals requires improvement. PMID:23228908

  7. GHG emission control and solid waste management for megacities with inexact inputs: a case study in Beijing, China.

    PubMed

    Lu, Hongwei; Sun, Shichao; Ren, Lixia; He, Li

    2015-03-01

    This study advances an integrated MSW management model under inexact input information for the city of Beijing, China. The model is capable of simultaneously generating MSW management policies, performing GHG emission control, and addressing system uncertainty. Results suggest that: (1) a management strategy with minimal system cost can be obtained even when suspension of certain facilities becomes unavoidable through specific increments of the remaining ones; (2) expansion of facilities depends only on actual needs, rather than enabling the full usage of existing facilities, although it may prove to be a costly proposition; (3) adjustment of waste-stream diversion ratio directly leads to a change in GHG emissions from different disposal facilities. Results are also obtained from the comparison of the model with a conventional one without GHG emissions consideration. It is indicated that (1) the model would reduce the net system cost by [45, 61]% (i.e., [3173, 3520] million dollars) and mitigate GHG emissions by [141, 179]% (i.e., [76, 81] million tons); (2) increased waste would be diverted to integrated waste management facilities to prevent overmuch CH4 emission from the landfills. PMID:25463222

  8. Knowledge and Skills of Sexual Abuse Prevention: A Study on School-Aged Children in Beijing, China.

    PubMed

    Jin, Yichen; Chen, Jingqi; Yu, Buyi

    2016-01-01

    To examine the level of child sexual abuse prevention knowledge and skills in a sample of school-aged children, a total of 559 children from first to fifth grade were recruited from one primary school in Beijing, China. Participants were asked to finish a questionnaire surveying their knowledge and skills of child sexual abuse prevention. Results showed that accurate rate of knowledge on child sexual abuse prevention were between 44.0% and 80.0%. Percentage of participants having applied the self-protection skills of "saying 'no,'" "going away," and "telling adults" properly in hypothetical situations was 57.4%, 28.3%, and 48.3%, respectively. Third-to-fifth graders had a better performance than first-to-second graders, and girls performed better than boys. Findings suggest that Chinese school-aged children are in need of knowledge and skills related to child sexual abuse prevention, and education programs should be developed as soon as possible. PMID:27561123

  9. Ambient particulate air pollution and circulating antioxidant enzymes: A repeated-measure study in healthy adults in Beijing, China.

    PubMed

    Wu, Shaowei; Wang, Bin; Yang, Di; Wei, Hongying; Li, Hongyu; Pan, Lu; Huang, Jing; Wang, Xin; Qin, Yu; Zheng, Chanjuan; Shima, Masayuki; Deng, Furong; Guo, Xinbiao

    2016-01-01

    The association of systemic antioxidant activity with ambient air pollution has been unclear. A panel of 40 healthy college students underwent repeated blood collection for 12 occasions under three exposure scenarios before and after relocating from a suburban area to an urban area in Beijing, China in 2010-2011. We measured various air pollutants including fine particles (PM2.5) and determined circulating levels of antioxidant enzymes extracellular superoxide dismutase (EC-SOD) and glutathione peroxidase 1 (GPX1) in the laboratory. An interquartile range increase of 63.4 μg/m(3) at 3-d PM2.5 moving average was associated with a 6.3% (95% CI: 0.6, 12.4) increase in EC-SOD and a 5.5% (95% CI: 1.3, 9.8) increase in GPX1. Several PM2.5 chemical constituents, including negative ions (nitrate and chloride) and metals (e.g., iron and strontium), were consistently associated with increases in EC-SOD and GPX1. Our results support activation of circulating antioxidant enzymes following exposure to particulate air pollution. PMID:26074023

  10. A preliminary risk assessment of potential exposure to naturally occurring estrogens from Beijing (China) market milk products.

    PubMed

    Chen, Chen; Mi, Xiaoxia; Yuan, Yuwei; Chen, Gang; Ren, Li; Wang, Kaiqiang; Zhu, Dan; Qian, Yongzhong

    2014-09-01

    This study was conducted to determine the occurrence of the natural steroid hormones estrone (E1), 17α-estradiol (αE2), 17β-estradiol (βE2) and estriol (E3) in 38 commercial milk samples obtained from markets in Beijing, China. Liquid Chromatography coupled with tandem mass spectrometry (LC-MS/MS) was employed to determine estrogens levels. The concentrations of E1, αE2, βE2 and E3 in different milk products varied from 0-146.12 ng/L, 0-70.12 ng/L, 0-31.85 ng/L to 0-2.18 ng/L, respectively. We compared exposures to estrogens through milk consumption with acceptable daily intakes (ADIs) and threshold for toxicological concern (TTC) to determine whether estrogen intakes from milk consumption are larger or smaller than the toxicity-based benchmarks. The combined margin of safety MOS (MOST) for total estrogens are about 72-99, 118-161, 539-1104, for 2-4, 4-7 year-old residential children, and adults, respectively. The lowest MOST for children of 2-4 years old result from comparing total of estrogens with the lowest TTC value (0.15 μg/person/day) (MOS=3.5). The MOS values suggest that the individual and total estrogens that may present in milk are not causing a health risk for the local residents, including young children. PMID:24910459

  11. Study of the distribution of non-point source pollution in the watershed of the Miyun Reservoir, Beijing, China.

    PubMed

    Wang, X; Li, T; Xu, A; He, W

    2001-01-01

    Nitrogen and phosphorus are major nutrients to cause eutrophication to degrade the water quality of the Miyun Reservoir, a very important drinking water source of Beijing in China. These are mainly from non-point sources. The watershed in Miyun County is selected as the study region with a total area of 1400 km2. Four typical monitoring catchments and two experimental units were used to monitor the precipitation, runoff, sediment yield and pollutant loading related to various land uses in the meantime. The results show that the total nutrient loss amount of TN and TP is 898.07 t/a, and 40.70 t/a, respectively, in which nutrient N and P carried by runoff is 91.3% and 77.3%, respectively. There is relatively heavier soil erosion at the northern mountain area whereas the main nutrient loss occurs near the northeast rim of the reservoir. Different land uses influence the loss of non-point source pollutants. The amount of nutrient loss from agricultural land per unit is the highest, nutrient loss from forestry is the second highest and that from grassland is the lowest. However, due to the variability of land use areas, agricultural land contributes the greatest amount of TP and forestry lands the greatest amount of TN. PMID:11724492

  12. Concentrations, sources and spatial distribution of polycyclic aromatic hydrocarbons in soils from Beijing, Tianjin and surrounding areas, North China

    PubMed Central

    Wang, Wentao; Massey Simonich, Staci L.; Xue, Miao; Zhao, Jingyu; Zhang, Na; Wang, Rong; Cao, Jun; Tao, Shu

    2013-01-01

    The concentrations, profiles, sources and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) were determined in 40 surface soil samples collected from Beijing, Tianjin and surrounding areas, North China in 2007, and all sampling sites were far from industrial areas, roadsides and other pollution sources, and across a range of soil types in remote, rural villages and urban areas. The total concentrations of 16 PAHs ranged from 31.6 to 1475.0 ng/g, with an arithmetic average of 336.4 ng/g. The highest PAH concentrations were measured in urban soils, followed by rural village soils and soils from remote locations. The remote–rural village–urban PAH concentration gradient was related to population density, gross domestic product (GDP), long-range atmospheric transport and different types of land use. In addition, the PAH concentration was well correlated with the total organic carbon (TOC) concentration of the soil. The PAH profile suggested that coal combustion and biomass burning were primary PAH sources. PMID:20199833

  13. Sexual Stigma, Coping Styles, and Psychological Distress: A Longitudinal Study of Men Who Have Sex with Men in Beijing, China

    PubMed Central

    Choi, Kyung-Hee; Steward, Wayne T.; Miège, Pierre; Hudes, Esther; Gregorich, Steven E.

    2015-01-01

    The direct link between stigma against sexual minorities and psychological distress is well established. However, few studies have examined the potential mediating roles of avoidant and social support coping in the relationships between internalized and anticipated stigma associated with homosexuality and depressive symptoms and anxiety among Chinese men who have sex with men (MSM). We recruited a longitudinal sample of 493 MSM in Beijing, China from 2011 to 2012. Participants completed computer-based questionnaires at baseline, 6 months, and 12 months. We found significant indirect effects of anticipated MSM stigma on symptoms of both depression and anxiety via avoidant coping: anticipated MSM stigma at baseline was significantly associated with avoidant coping (B = 0.523, p < 0.001) at 6 months and, conditional on anticipated MSM stigma, avoidant coping had a significant positive effect on depressive symptoms and anxiety at 12 months (B = 0.069, p = 0.001 and B=0.071, p=0.014). In contrast, no significant indirect effects of anticipated MSM stigma on either psychological distress outcome via social support coping were found. No significant indirect effects of internalized MSM stigma via either avoidant or social support coping were found. These results underscore the need for interventions that address anticipations of stigma and the use of avoidant coping techniques to manage such anticipations. PMID:26679303

  14. Woody species diversity in forest plantations in a mountainous region of Beijing, China: effects of sampling scale and species selection.

    PubMed

    Zhang, Yuxin; Zhang, Shuang; Ma, Keming; Fu, Bojie; Anand, Madhur

    2014-01-01

    The role of forest plantations in biodiversity conservation has gained more attention in recent years. However, most work on evaluating the diversity of forest plantations focuses only on one spatial scale; thus, we examined the effects of sampling scale on diversity in forest plantations. We designed a hierarchical sampling strategy to collect data on woody species diversity in planted pine (Pinus tabuliformis Carr.), planted larch (Larix principis-rupprechtii Mayr.), and natural secondary deciduous broadleaf forests in a mountainous region of Beijing, China. Additive diversity partition analysis showed that, compared to natural forests, the planted pine forests had a different woody species diversity partitioning pattern at multi-scales (except the Simpson diversity in the regeneration layer), while the larch plantations did not show multi-scale diversity partitioning patterns that were obviously different from those in the natural secondary broadleaf forest. Compare to the natural secondary broadleaf forests, the effects of planted pine forests on woody species diversity are dependent on the sampling scale and layers selected for analysis. Diversity in the planted larch forest, however, was not significantly different from that in the natural forest for all diversity components at all sampling levels. Our work demonstrated that the species selected for afforestation and the sampling scales selected for data analysis alter the conclusions on the levels of diversity supported by plantations. We suggest that a wide range of scales should be considered in the evaluation of the role of forest plantations on biodiversity conservation. PMID:25545860

  15. Spatial-Temporal Variations of Water Quality and Its Relationship to Land Use and Land Cover in Beijing, China.

    PubMed

    Chen, Xiang; Zhou, Weiqi; Pickett, Steward T A; Li, Weifeng; Han, Lijian

    2016-01-01

    Rapid urbanization with intense land use and land cover (LULC) change and explosive population growth has a great impact on water quality. The relationship between LULC characteristics and water quality provides important information for non-point sources (NPS) pollution management. In this study, we first quantified the spatial-temporal patterns of five water quality variables in four watersheds with different levels of urbanization in Beijing, China. We then examined the effects of LULC on water quality across different scales, using Pearson correlation analysis, redundancy analysis, and multiple regressions. The results showed that water quality was improved over the sampled years but with no significant difference (p > 0.05). However, water quality was significantly different among nonurban and both exurban and urban sites (p < 0.05). Forest land was positively correlated with water quality and affected water quality significantly (p < 0.05) within a 200 m buffer zone. Impervious surfaces, water, and crop land were negatively correlated with water quality. Crop land and impervious surfaces, however, affected water quality significantly (p < 0.05) for buffer sizes greater than 800 m. Grass land had different effects on water quality with the scales. The results provide important insights into the relationship between LULC and water quality, and thus for controlling NPS pollution in urban areas. PMID:27128934

  16. HIV-testing behavior among young migrant men who have sex with men (MSM) in Beijing, China.

    PubMed

    Song, Yan; Li, Xiaoming; Zhang, Liying; Fang, Xiaoyi; Lin, Xiuyun; Liu, Yinjie; Stanton, Bonita

    2011-02-01

    Previous studies suggested a rapid increase of HIV prevalence among men who have sex with men (MSM) in China in recent years, from 0.4% in 2004 to 5.8% in 2006. However, some MSM had never been tested for HIV. In order to expand the accessibility to HIV testing, understanding HIV-testing behavior and barriers among MSM is important. Using data collected from 307 young migrant MSM (aged 18-29 years) in 2009 in Beijing, we aimed to identify psychological and structural barriers to HIV testing. MSM were recruited through peer outreach, informal social networks, Internet outreach, and venue-based outreach. Participants completed a confidential self-administered questionnaire. Results show that about 72% of MSM ever had an HIV test. Logistic regression analysis indicated that the HIV-testing behavior was associated with sexual risk behaviors (e.g., multiple sexual partners and inconsistent condom use for anal sex) and history of sexually transmitted diseases. Eighty four MSM (28%) who never had an HIV test reported that the psychological barriers mainly were perceived low risk of HIV infection and fears of being stigmatized. The structural barriers reported inconvenience of doing test and lack of confidentiality. Future HIV prevention programs should be strengthened among MSM to increase their awareness of HIV risk. Efforts are needed to increase access to quality and confidential HIV testing among MSM and reduce stigma against MSM. PMID:21259130

  17. Sexual Stigma, Coping Styles, and Psychological Distress: A Longitudinal Study of Men Who Have Sex With Men in Beijing, China.

    PubMed

    Choi, Kyung-Hee; Steward, Wayne T; Miège, Pierre; Hudes, Esther; Gregorich, Steven E

    2016-08-01

    The direct link between stigma against sexual minorities and psychological distress is well established. However, few studies have examined the potential mediating roles of avoidant and social support coping in the relationships between internalized and anticipated stigma associated with homosexuality and depressive symptoms and anxiety among Chinese men who have sex with men (MSM). We recruited a longitudinal sample of 493 MSM in Beijing, China from 2011 to 2012. Participants completed computer-based questionnaires at baseline, 6, and 12 months. We found significant indirect effects of anticipated MSM stigma on symptoms of both depression and anxiety via avoidant coping: anticipated MSM stigma at baseline was significantly associated with avoidant coping (B = 0.523, p < 0.001) at 6 months and, conditional on anticipated MSM stigma, avoidant coping had a significant positive effect on depressive symptoms and anxiety at 12 months (B = 0.069, p = 0.001 and B = 0.071, p = 0.014). In contrast, no significant indirect effects of anticipated MSM stigma on either psychological distress outcome via social support coping were found. No significant indirect effects of internalized MSM stigma via either avoidant or social support coping were found. These results underscore the need for interventions that address anticipations of stigma and the use of avoidant coping techniques to manage such anticipations. PMID:26679303

  18. Woody Species Diversity in Forest Plantations in a Mountainous Region of Beijing, China: Effects of Sampling Scale and Species Selection

    PubMed Central

    Zhang, Yuxin; Zhang, Shuang; Ma, Keming; Fu, Bojie; Anand, Madhur

    2014-01-01

    The role of forest plantations in biodiversity conservation has gained more attention in recent years. However, most work on evaluating the diversity of forest plantations focuses only on one spatial scale; thus, we examined the effects of sampling scale on diversity in forest plantations. We designed a hierarchical sampling strategy to collect data on woody species diversity in planted pine (Pinus tabuliformis Carr.), planted larch (Larix principis-rupprechtii Mayr.), and natural secondary deciduous broadleaf forests in a mountainous region of Beijing, China. Additive diversity partition analysis showed that, compared to natural forests, the planted pine forests had a different woody species diversity partitioning pattern at multi-scales (except the Simpson diversity in the regeneration layer), while the larch plantations did not show multi-scale diversity partitioning patterns that were obviously different from those in the natural secondary broadleaf forest. Compare to the natural secondary broadleaf forests, the effects of planted pine forests on woody species diversity are dependent on the sampling scale and layers selected for analysis. Diversity in the planted larch forest, however, was not significantly different from that in the natural forest for all diversity components at all sampling levels. Our work demonstrated that the species selected for afforestation and the sampling scales selected for data analysis alter the conclusions on the levels of diversity supported by plantations. We suggest that a wide range of scales should be considered in the evaluation of the role of forest plantations on biodiversity conservation. PMID:25545860

  19. Nitrogen and phosphorus associating with different size suspended solids in roof and road runoff in Beijing, China.

    PubMed

    Wu, Junliang; Ren, Yufen; Wang, Xuemei; Wang, Xiaoke; Chen, Liding; Liu, Gangcai

    2015-10-01

    Roofs and roads, accounting for a large portion of the urban impervious land surface, have contributed significantly to urban nonpoint pollution. In this study, in Beijing, China, roof and road runoff are sampled to measure the suspended solids (SS), nitrogen (N), and phosphorus (P) contained in particles with different sizes. The SS content in the road runoff (151.59 mg/L) was sevenfold that in the roof runoff (21.13 mg/L, p < 0.05). The SS contained more coarse particulates in the roof runoff than in road runoff. The small particulates in the range of 0.45-50 μm consisted of 59 % SS in the roof runoff and 94 % SS in the road runoff. P was mainly attached to particle sizes of 10-50 μm in the roof (73 %) and road (48 %) runoffs, while N was mainly in a dissolved phase state in both runoffs. So, the different associations of N and P raise a challenge in preventing stormwater pollution in urban environments. PMID:26036583

  20. Spatial-Temporal Variations of Water Quality and Its Relationship to Land Use and Land Cover in Beijing, China

    PubMed Central

    Chen, Xiang; Zhou, Weiqi; Pickett, Steward T. A.; Li, Weifeng; Han, Lijian

    2016-01-01

    Rapid urbanization with intense land use and land cover (LULC) change and explosive population growth has a great impact on water quality. The relationship between LULC characteristics and water quality provides important information for non-point sources (NPS) pollution management. In this study, we first quantified the spatial-temporal patterns of five water quality variables in four watersheds with different levels of urbanization in Beijing, China. We then examined the effects of LULC on water quality across different scales, using Pearson correlation analysis, redundancy analysis, and multiple regressions. The results showed that water quality was improved over the sampled years but with no significant difference (p > 0.05). However, water quality was significantly different among nonurban and both exurban and urban sites (p < 0.05). Forest land was positively correlated with water quality and affected water quality significantly (p < 0.05) within a 200 m buffer zone. Impervious surfaces, water, and crop land were negatively correlated with water quality. Crop land and impervious surfaces, however, affected water quality significantly (p < 0.05) for buffer sizes greater than 800 m. Grass land had different effects on water quality with the scales. The results provide important insights into the relationship between LULC and water quality, and thus for controlling NPS pollution in urban areas. PMID:27128934

  1. Analysis of Drug Resistance Determinants in Klebsiella pneumoniae Isolates from a Tertiary-Care Hospital in Beijing, China

    PubMed Central

    Wang, Qi; Woo, Patrick C. Y.; Tan, Lin; Jing, Hua; Gao, George F.; Liu, Cui Hua

    2012-01-01

    Background The rates of multidrug-resistant (MDR), extensively drug-resistant (XDR) and pandrug-resistant (PDR) isolates among Enterobacteriaceae isolates, particularly Klebsiella pneumoniae, have risen substantially worldwide. Methodology/Principal Findings To better understand the molecular mechanisms of drug resistance in K. pneumoniae, we analyzed the drug resistance determinants for K. pneumoniae isolates collected from the 306 Hospital, a tertiary-care hospital in Beijing, China, for the period of September 1, 2010-October 31, 2011. Drug susceptibility testing, PCR amplification and sequencing of the drug resistance determinants were performed. Conjugation experiments were conducted to examine the natural ability of drug resistance to disseminate among Enterobacteriaceae strains using a sodium azide-resistant Escherichia coli J53 strain as a recipient. Among the 223 consecutive non-repetitive K. pneumoniae isolates included in this study, 101 (45.3%) were extended-spectrum beta-lactamases (ESBLs) positive. The rates of MDR, XDR, and PDR isolates were 61.4% (n = 137), 22.0% (n = 49), and 1.8% (n = 4), respectively. Among the tested drug resistance-associated genes, the following ones were detected at relatively high rates blaCTX-M-10 (80, 35.9%), aacC2 (73, 32.7%), dhfr (62, 27.8%), qnrS (58, 26.0%), aacA4 (57, 25.6%), aadA1 (56, 25.1%). Results from conjugation experiments indicate that many of the drug resistance genes were transmissible. Conclusions/Significance Our data give a “snapshot” of the complex genetic background responsible for drug resistance in K. pneumoniae in China and demonstrate that a high degree of awareness and monitoring of those drug resistance determinants are urgently needed in order to better control the emergence and transmission of drug-resistant K. pneumoniae isolates in hospital settings. PMID:22860106

  2. Fine Particulate Matter Pollution and Hospital Admissions for Respiratory Diseases in Beijing, China.

    PubMed

    Xiong, Qiulin; Zhao, Wenji; Gong, Zhaoning; Zhao, Wenhui; Tang, Tao

    2015-09-01

    Fine particulate matter has become the premier air pollutant of Beijing in recent years, enormously impacting the environmental quality of the city and the health of the residents. Fine particles with aerodynamic diameters of 0~0.3 μm, 0.3~0.5 μm, and 0.5~1.0 μm, from the yeasr 2007 to 2012, were monitored, and the hospital data about respiratory diseases during the same period was gathered and calculated. Then the correlation between respiratory health and fine particles was studied by spatial analysis and grey correlation analysis. The results showed that the aerial fine particulate matter pollution was mainly distributed in the Zizhuyuan sub-district office. There was a certain association between respiratory health and fine particles. Outpatients with respiratory system disease in this study area were mostly located in the southeastern regions (Balizhuang sub-district office, Ganjiakou sub-district office, Wanshoulu sub-district office, and Yongdinglu sub-district office) and east-central regions (Zizhuyuan sub-district office and Shuangyushu sub-district office) of the study area. Correspondingly, PM₁ (particulate matter with aerodynamic diameter smaller than 1.0 um) concentrations in these regions were higher than those in any other regions. Grey correlation analysis results showed that the correlation degree of the fine particle concentration with the number of outpatients is high, and the smaller fine particles had more obvious effects on respiratory system disease than larger particles. PMID:26402691

  3. Chemical characteristics of size-resolved PM₂.₅ at a roadside environment in Beijing, China.

    PubMed

    Song, Shaojie; Wu, Ye; Jiang, Jingkun; Yang, Liu; Cheng, Yuan; Hao, Jiming

    2012-02-01

    Size-resolved particulate matter in the three size ranges (0.2-0.5 μm, 0.5-1.0 μm, and 1.0-2.5 μm) were collected at a roadside site in Beijing during and after the 2008 Olympic Games. The concentrations of PM mass, 14 elements, 3 major inorganic ions, and carbonaceous species were determined. The main contributors to PM(2.5) were crustal sources, vehicle emissions, secondary aerosol formation along with coal combustion, biomass from burning, and industrial processes, with vehicle emissions contributing more to roadside PM(2.5) than in the urban areas. The peaks at 0.5-1.0 μm in summer for PM mass and inorganic ions were most likely due to secondary aerosol formation, whereas the peaks at 0.2-0.5 μm in winter for PM mass and some elements were probably attributed to combustion from heating sources. The temporary control measures applied during the Olympics showed different effects on various emission sources and chemical species. PMID:22230088

  4. Fine Particulate Matter Pollution and Hospital Admissions for Respiratory Diseases in Beijing, China

    PubMed Central

    Xiong, Qiulin; Zhao, Wenji; Gong, Zhaoning; Zhao, Wenhui; Tang, Tao

    2015-01-01

    Fine particulate matter has become the premier air pollutant of Beijing in recent years, enormously impacting the environmental quality of the city and the health of the residents. Fine particles with aerodynamic diameters of 0~0.3 μm, 0.3~0.5 μm, and 0.5~1.0 μm, from the yeasr 2007 to 2012, were monitored, and the hospital data about respiratory diseases during the same period was gathered and calculated. Then the correlation between respiratory health and fine particles was studied by spatial analysis and grey correlation analysis. The results showed that the aerial fine particulate matter pollution was mainly distributed in the Zizhuyuan sub-district office. There was a certain association between respiratory health and fine particles. Outpatients with respiratory system disease in this study area were mostly located in the southeastern regions (Balizhuang sub-district office, Ganjiakou sub-district office, Wanshoulu sub-district office, and Yongdinglu sub-district office) and east-central regions (Zizhuyuan sub-district office and Shuangyushu sub-district office) of the study area. Correspondingly, PM1 (particulate matter with aerodynamic diameter smaller than 1.0 um) concentrations in these regions were higher than those in any other regions. Grey correlation analysis results showed that the correlation degree of the fine particle concentration with the number of outpatients is high, and the smaller fine particles had more obvious effects on respiratory system disease than larger particles. PMID:26402691

  5. Spatial Distribution, Sources Apportionment and Health Risk of Metals in Topsoil in Beijing, China

    PubMed Central

    Sun, Chunyuan; Zhao, Wenji; Zhang, Qianzhong; Yu, Xue; Zheng, Xiaoxia; Zhao, Jiayin; Lv, Ming

    2016-01-01

    In order to acquire the pollution feature and regularities of distribution of metals in the topsoil within the sixth ring road in Beijing, a total of 46 soil samples were collected, and the concentrations of twelve elements (Nickel, Ni, Lithium, Li, Vanadium, V, Cobalt, Co, Barium, Ba, Strontium, Sr, Chrome, Cr, Molybdenum, Mo, Copper, Cu, Cadmium, Cd, Zinc, Zn, Lead, Pb) were analyzed. Geostatistics and multivariate statistics were conducted to identify spatial distribution characteristics and sources. In addition, the health risk of the analyzed heavy metals to humans (adult) was evaluated by an U.S. Environmental Protection Agency health risk assessment model. The results indicate that these metals have notable variation in spatial scale. The concentration of Cr was high in the west and low in the east, while that of Mo was high in the north and low in the south. High concentrations of Cu, Cd, Zn, and Pb were found in the central part of the city. The average enrichment degree of Cd is 5.94, reaching the standard of significant enrichment. The accumulation of Cr, Mo, Cu, Cd, Zn, and Pb is influenced by anthropogenic activity, including vehicle exhaustion, coal burning, and industrial processes. Health risk assessment shows that both non-carcinogenic and carcinogenic risks of selected heavy metals are within the safety standard and the rank of the carcinogenic risk of the four heavy metals is Cr > Co > Ni > Cd. PMID:27447657

  6. Episode-Based Evolution Pattern Analysis of Haze Pollution: Method Development and Results from Beijing, China.

    PubMed

    Zheng, Guangjie; Duan, Fengkui; Ma, Yongliang; Zhang, Qiang; Huang, Tao; Kimoto, Takashi; Cheng, Yafang; Su, Hang; He, Kebin

    2016-05-01

    Haze episodes occurred in Beijing repeatedly in 2013, resulting in 189 polluted days. These episodes differed in terms of sources, formation processes, and chemical composition and thus required different control policies. Therefore, an overview of the similarities and differences among these episodes is needed. For this purpose, we conducted one-year online observations and developed a program that can simultaneously divide haze episodes and identify their shapes. A total of 73 episodes were identified, and their shapes were linked with synoptic conditions. Pure-haze events dominated in wintertime, whereas mixed haze-dust (PM2.5/PM10 < 60%) and mixed haze-fog (Aerosol Water/PM2.5 ∼ 0.3) events dominated in spring and summer-autumn, respectively. For all types, increase of ratio of PM2.5 in PM10 was typically achieved before PM2.5 reached ∼150 μg/m(3). In all PM2.5 species observed, organic matter (OM) was always the most abundant component (18-60%), but it was rarely the driving factor: its relative contribution usually decreased as the pollution level increased. The only OM-driven episode observed was associated with intensive biomass-burning activities. In comparison, haze evolution generally coincided with increasing sulfur and nitrogen oxidation ratios (SOR and NOR), indicating the enhanced production of secondary inorganic species. Applicability of these conclusions required further tests with simultaneously multisite observations. PMID:27050081

  7. Spatial Distribution, Sources Apportionment and Health Risk of Metals in Topsoil in Beijing, China.

    PubMed

    Sun, Chunyuan; Zhao, Wenji; Zhang, Qianzhong; Yu, Xue; Zheng, Xiaoxia; Zhao, Jiayin; Lv, Ming

    2016-01-01

    In order to acquire the pollution feature and regularities of distribution of metals in the topsoil within the sixth ring road in Beijing, a total of 46 soil samples were collected, and the concentrations of twelve elements (Nickel, Ni, Lithium, Li, Vanadium, V, Cobalt, Co, Barium, Ba, Strontium, Sr, Chrome, Cr, Molybdenum, Mo, Copper, Cu, Cadmium, Cd, Zinc, Zn, Lead, Pb) were analyzed. Geostatistics and multivariate statistics were conducted to identify spatial distribution characteristics and sources. In addition, the health risk of the analyzed heavy metals to humans (adult) was evaluated by an U.S. Environmental Protection Agency health risk assessment model. The results indicate that these metals have notable variation in spatial scale. The concentration of Cr was high in the west and low in the east, while that of Mo was high in the north and low in the south. High concentrations of Cu, Cd, Zn, and Pb were found in the central part of the city. The average enrichment degree of Cd is 5.94, reaching the standard of significant enrichment. The accumulation of Cr, Mo, Cu, Cd, Zn, and Pb is influenced by anthropogenic activity, including vehicle exhaustion, coal burning, and industrial processes. Health risk assessment shows that both non-carcinogenic and carcinogenic risks of selected heavy metals are within the safety standard and the rank of the carcinogenic risk of the four heavy metals is Cr > Co > Ni > Cd. PMID:27447657

  8. Source Apportionment of Elemental Carbon in Beijing, China: Insights from Radiocarbon and Organic Marker Measurements.

    PubMed

    Zhang, Yan-Lin; Schnelle-Kreis, Jürgen; Abbaszade, Gülcin; Zimmermann, Ralf; Zotter, Peter; Shen, Rong-rong; Schäfer, Klaus; Shao, Longyi; Prévôt, André S H; Szidat, Sönke

    2015-07-21

    Elemental carbon (EC) or black carbon (BC) in the atmosphere has a strong influence on both climate and human health. In this study, radiocarbon ((14)C) based source apportionment is used to distinguish between fossil fuel and biomass burning sources of EC isolated from aerosol filter samples collected in Beijing from June 2010 to May 2011. The (14)C results demonstrate that EC is consistently dominated by fossil-fuel combustion throughout the whole year with a mean contribution of 79% ± 6% (ranging from 70% to 91%), though EC has a higher mean and peak concentrations in the cold season. The seasonal molecular pattern of hopanes (i.e., a class of organic markers mainly emitted during the combustion of different fossil fuels) indicates that traffic-related emissions are the most important fossil source in the warm period and coal combustion emissions are significantly increased in the cold season. By combining (14)C based source apportionment results and picene (i.e., an organic marker for coal emissions) concentrations, relative contributions from coal (mainly from residential bituminous coal) and vehicle to EC in the cold period were estimated as 25 ± 4% and 50 ± 7%, respectively, whereas the coal combustion contribution was negligible or very small in the warm period. PMID:26114602

  9. Nonlinear and threshold of the association between meteorological factors and bacillary dysentery in Beijing, China.

    PubMed

    Li, Z J; Zhang, X J; Hou, X X; Xu, S; Zhang, J S; Song, H B; Lin, H L

    2015-12-01

    Previous studies examining the weather-bacillary dysentery association were of a large time scale (monthly or weekly) and examined the linear relationship without checking the linearity assumption. We examined this association in Beijing at a daily scale based on the exposure-response curves using generalized additive models. Our analyses suggested that there were thresholds for effects of temperature and relative humidity, with an approximately linear effect for temperature >12·5 °C [excess risk (ER) for 1 °C increase: 1·06%, 95% confidence interval (CI) 0·63-1·49 on lag day 3] and for relative humidity >40% (ER for 1% increase: 0·18%, 95% CI 0·12-0·24 at lag day 4); and there were linear effects of rainfall (ER for 1-mm increase: 0·22%, 95% CI 0·12-0·32), negative effects for wind speed (ER: -2·91%, 95% CI -4·28 to -1·52 at lag day 3) and sunshine duration (ER: -0·25% 95% CI -0·43 to -0·07 at lag day 4). This study suggests that there are thresholds for the effects of temperature and relative humidity on bacillary dysentery, and these findings should be considered in its prevention and control programmes. PMID:26027678

  10. An Exploration of the Potential Impact of the Integrated Experiential Learning Curriculum in Beijing, China

    ERIC Educational Resources Information Center

    Zhang, Danhui; Campbell, Todd

    2012-01-01

    This study examines the effectiveness of the Integrated Experiential Learning Curriculum (IELC) in China. This curriculum was developed to engage Chinese elementary students in science to cultivate a scientifically literate society by focusing science instruction on practical applications of scientific knowledge. Cornerstones of the approach…

  11. Willingness to Use the Oral Fluid HIV Rapid Test among Men Who Have Sex with Men in Beijing, China

    PubMed Central

    Li, Dongliang; Liu, Yingjie; Pan, Stephen W.; Qi, Xiao; Wang, Bo; Luo, Fengji; Xiao, Dong; Shao, Yiming; Ruan, Yuhua

    2013-01-01

    Background Early detection of HIV infection enables timely care and treatment. However, many men who have sex with men (MSM) remain unaware of their HIV status because they do not or are unable to access HIV testing services. Oral fluid HIV rapid tests have the potential to increase HIV testing. This study is the first to evaluate willingness to use the oral fluid test among MSM in China. Methods A cross-sectional study was conducted in Beijing from July to October, 2012. Data were collected by self-administered questionnaires. Results Of 262 who participated in the survey, 223(85.1%) reported that they were willing to use the oral fluid HIV rapid test. Willingness to use the oral fluid test was associated with higher education (adjusted odds ratio (AOR): 2.40, 95% confidence interval (CI): 1.13–5.10), lack of unprotected anal intercourse (UAI) with male partners in the past one month (AOR: 2.38; 95% 95%CI: 1.15–4.95), having taken more than 4 HIV tests (AOR: 3.54; 95%CI:1.52–8.28), and having ever heard of the oral fluid HIV rapid test from gay friends or gay organizations (AOR: 3.24, 95%CI: 1.40–7.51). Among those who expressed willingness to use the oral fluid HIV rapid test, the median amount of money they were willing to pay was 8 dollars. Among the 39 participants who were unwilling to use the oral fluid test, 79.5% (31/39) expressed concerns about the accuracy of the oral fluid HIV rapid test results and 17.9%(7/39) reported that they were not familiar with the oral fluid test and did not know how to use such a test. Conclusions A high proportion of MSM in Beijing appear to be willing to use the oral fluid HIV rapid test. Appropriate cost and education measures could help improve acceptance of the oral fluid test. PMID:23717645

  12. Chemical apportionment of aerosol optical properties during the Asia-Pacific Economic Cooperation summit in Beijing, China

    NASA Astrophysics Data System (ADS)

    Han, Tingting; Xu, Weiqi; Chen, Chen; Liu, Xingang; Wang, Qingqing; Li, Jie; Zhao, Xiujuan; Du, Wei; Wang, Zifa; Sun, Yele

    2015-12-01

    We have investigated the chemical and optical properties of aerosol particles during the 2014 Asia-Pacific Economic Cooperation (APEC) summit in Beijing, China, using the highly time-resolved measurements by a high-resolution aerosol mass spectrometer and a cavity attenuated phase shift extinction monitor. The average (±σ) extinction coefficient (bext) and absorption coefficient (bap) were 186.5 (±184.5) M m-1 and 23.3 (±21.9) M m-1 during APEC, which were decreased by 63% and 56%, respectively, compared to those before APEC primarily due to strict emission controls. The aerosol composition and size distributions showed substantial changes during APEC; as a response, the mass scattering efficiency (MSE) of PM1 was decreased from 4.7 m2 g-1 to 3.5 m2 g-1. Comparatively, the average single-scattering albedo (SSA) remained relatively unchanged, illustrating the synchronous reductions of bext and bap during APEC. MSE and SSA were found to increase as function of the oxidation degree of organic aerosol (OA), indicating a change of aerosol optical properties during the aging processes. The empirical relationships between chemical composition and particle extinction were established using a multiple linear regression model. Our results showed the largest contribution of ammonium nitrate to particle extinction, accounting for 35.1% and 29.3% before and during APEC, respectively. This result highlights the important role of ammonium nitrate in the formation of severe haze pollution during this study period. We also observed very different optical properties of primary and secondary aerosol. Owing to emission controls in Beijing and surrounding regions and also partly the influences of meteorological changes, the average bext of secondary aerosol during APEC was decreased by 71% from 372.3 M m-1 to 108.5 M m-1, whereas that of primary aerosol mainly from cooking, traffic, and biomass burning emissions showed a smaller reduction from 136.7 M m-1 to 71.3 M m-1. As a result

  13. Hygroscopic growth of urban aerosol particles in Beijing (China) during wintertime: a comparison of three experimental methods

    NASA Astrophysics Data System (ADS)

    Meier, J.; Wehner, B.; Massling, A.; Birmili, W.; Nowak, A.; Gnauk, T.; Brüggemann, E.; Herrmann, H.; Min, H.; Wiedensohler, A.

    2009-09-01

    The hygroscopic properties of atmospheric aerosols are highly relevant for the quantification of radiative effects in the atmosphere, but also of interest for the assessment of particle health effects upon inhalation. This article reports measurements of aerosol particle hygroscopicity in the highly polluted urban atmosphere of Beijing, China in January 2005. The meteorological conditions corresponded to a relatively cold and dry atmosphere. Three different methods were used: 1) A combination of Humidifying Differential Mobility Particle Sizer (H-DMPS) and Twin Differential Mobility Particle Sizer (TDMPS) measurements, 2) A Hygroscopic Tandem Differential Mobility Analyzer (H-TDMA), and 3) A simplistic solubility model fed by chemical particle composition determined from Micro Orifice Uniform Deposit Impactor (MOUDI) samples. From the H-DMPS and TDMPS particle number size distributions, a size-resolved descriptive hygroscopic growth factor (DHGF) was determined for the relative humidities (RH) 55%, 77% and 90%, and particle diameters between 30 and 400 nm. In Beijing, the highest DHGFs were observed for accumulation mode particles, 1.40 (±0.03) at 90% RH. DHGF decreased significantly with particle size, reaching 1.04 (±0.15) at 30 nm. H-TDMA data also suggest a decrease in growth factor towards the biggest particles investigated (350 nm), associated with an increasing fraction of nearly hydrophobic particles. The agreement between the H-DMPS/TDMPS and H-TDMA methods was satisfactory in the accumulation mode size range (100-400 nm). In the Aitken mode range (<100 nm), the H-DMPS/TDMPS method yielded growth factors lower by up to 0.1 at 90% RH. The application of the solubility model based on measured chemical composition clearly reproduced the size-dependent trend in hygroscopic particle growth observed by the other methods. In the case of aerosol dominated by inorganic ions, the composition-derived growth factors tended to agree (± 0.05) or underestimate (up to

  14. Distribution of pilus islands and alpha-like protein genes of group B Streptococcus colonized in pregnant women in Beijing, China.

    PubMed

    Lu, B; Wang, D; Zhou, H; Zhu, F; Li, D; Zhang, S; Shi, Y; Cui, Y; Huang, L; Wu, H

    2015-06-01

    Group B Streptococcus (GBS) is one of the major pathogens of severe newborn sepsis and meningitis. Understanding its regional molecular epidemiology is helpful for regulating efficient prevention practice. A total of 160 GBS strains were collected from colonized pregnant women in six hospital settings in Beijing, China. Polymerase chain reaction (PCR) assays were used to identify the pilus island (PI), alp genes profiling of the alpha-like protein family, and capsular polysaccharide (cps) serotyping. The clonal relationships between strains were investigated using multilocus sequence typing (MLST). All isolates carried at least one pilus island. The most frequently detected pilus island was PI-2a alone (70 isolates, 43.8 %). The most prevalent alp gene was rib (60 isolates, 37.5 %). Moreover, a strong association was noted between alp genes, serotyping, and pilus island profiles. The GBS isolates under study hinted similar molecular epidemical characteristics in Beijing to those reported worldwide, but having their regional distributional features. PMID:25669160

  15. Sectoral roles in greenhouse gas emissions and policy implications for energy utilization and carbon emissions trading: a case study of Beijing, China.

    PubMed

    Ge, Jianping; Lei, Yalin; Xu, Qun; Wang, Xibo

    2016-01-01

    In this study, a decomposition and emissions matrix is developed to identify the roles (giver or taker) played by the sectors in the greenhouse gas emissions for the economy of Beijing in China. Our results indicate that services were the most important emitter if we consider the total (direct and indirect) emissions. In addition to Construction, Scientific studies and technical services and Finance sectors of services were the largest takers. They have a large role in boosting greenhouse gas emissions throughout the economy of Beijing. As the basis and supporter of production activities, the electricity production and the transportation sectors were the greatest givers. More emphasis should be placed on using clean energy and carbon capture and storage technologies to reduce emissions within these sectors. Based on the roles played by these sectors in greenhouse gas emissions, some policy implications were proposed for energy utilization and carbon emissions trading. PMID:27547661

  16. Beijing Ancient Observatory

    NASA Astrophysics Data System (ADS)

    Shi, Yunli

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

  17. China-U.S. Conference on Education. Collected Papers. (Beijing, People's Republic of China, July 9-13, 1997).

    ERIC Educational Resources Information Center

    Walz, Garry R.

    This book contains papers presented by educators during the China-U.S. Conference on Education in July, 1997. Only papers prepared by American authors were received and included in this collection. Chapters included are (1) "Art, Education, and Community: Arts Genesis, Inc." (C. S. Kestler); (2) "Applications of Portfolio Assessment in a Teaching…

  18. Effect of Landscape Pattern on Insect Species Density within Urban Green Spaces in Beijing, China

    PubMed Central

    Su, Zhimin; Li, Xiaoma; Zhou, Weiqi; Ouyang, Zhiyun

    2015-01-01

    Urban green space is an important refuge of biodiversity in urban areas. Therefore, it is crucial to understand the relationship between the landscape pattern of green spaces and biodiversity to mitigate the negative effects of urbanization. In this study, we collected insects from 45 green patches in Beijing during July 2012 using suction sampling. The green patches were dominated by managed lawns, mixed with scattered trees and shrubs. We examined the effects of landscape pattern on insect species density using hierarchical partitioning analysis and partial least squares regression. The results of the hierarchical partitioning analysis indicated that five explanatory variables, i.e., patch area (with 19.9% independent effects), connectivity (13.9%), distance to nearest patch (13.8%), diversity for patch types (11.0%), and patch shape (8.3%), significantly contributed to insect species density. With the partial least squares regression model, we found species density was negatively related to patch area, shape, connectivity, diversity for patch types and proportion of impervious surface at the significance level of p < 0.05 and positively related to proportion of vegetated land. Regression tree analysis further showed that the highest species density was found in green patches with an area <500 m2. Our results indicated that improvement in habitat quality, such as patch area and connectivity that are typically thought to be important for conservation, did not actually increase species density. However, increasing compactness (low-edge) of patch shape and landscape composition did have the expected effect. Therefore, it is recommended that the composition of the surrounding landscape should be considered simultaneously with planned improvements in local habitat quality. PMID:25793897

  19. Effect of landscape pattern on insect species density within urban green spaces in Beijing, China.

    PubMed

    Su, Zhimin; Li, Xiaoma; Zhou, Weiqi; Ouyang, Zhiyun

    2015-01-01

    Urban green space is an important refuge of biodiversity in urban areas. Therefore, it is crucial to understand the relationship between the landscape pattern of green spaces and biodiversity to mitigate the negative effects of urbanization. In this study, we collected insects from 45 green patches in Beijing during July 2012 using suction sampling. The green patches were dominated by managed lawns, mixed with scattered trees and shrubs. We examined the effects of landscape pattern on insect species density using hierarchical partitioning analysis and partial least squares regression. The results of the hierarchical partitioning analysis indicated that five explanatory variables, i.e., patch area (with 19.9% independent effects), connectivity (13.9%), distance to nearest patch (13.8%), diversity for patch types (11.0%), and patch shape (8.3%), significantly contributed to insect species density. With the partial least squares regression model, we found species density was negatively related to patch area, shape, connectivity, diversity for patch types and proportion of impervious surface at the significance level of p < 0.05 and positively related to proportion of vegetated land. Regression tree analysis further showed that the highest species density was found in green patches with an area <500 m2. Our results indicated that improvement in habitat quality, such as patch area and connectivity that are typically thought to be important for conservation, did not actually increase species density. However, increasing compactness (low-edge) of patch shape and landscape composition did have the expected effect. Therefore, it is recommended that the composition of the surrounding landscape should be considered simultaneously with planned improvements in local habitat quality. PMID:25793897

  20. Averaging period effects on the turbulent flux and transport efficiency during haze pollution in Beijing, China

    NASA Astrophysics Data System (ADS)

    Guo, Xiaofeng; Yang, Ting; Sun, Yele

    2015-08-01

    Based on observations at the heights of 140 and 280 m on the Beijing 325-m meteorological tower, this study presents an assessment of the averaging period effects on eddy-covariance measurements of the momentum/scalar flux and transport efficiency during wintertime haze pollution. The study period, namely from January 6 to February 28 2013, is divided into different episodes of particulate pollution, as featured by varied amounts of the turbulent exchange and conditions of the atmospheric stability. Overall, turbulent fluxes of the momentum and scalars (heat, water vapor, and CO2) increase with the averaging period, namely from 5, 15, and 30 up to 60 min, an outcome most evident during the `transient' episodes (each lasting for 2-3 days, i.e., preceded and followed by clean-air days with mean concentrations of PM1 less than 40 μg m-3). The conventional choice of 30 min is deemed to be appropriate for calculating the momentum flux and its transport efficiency. By comparison, scalar fluxes and their transport efficiencies appear more sensitive to the choice of an averaging period, particularly at the upper level (i.e., 280 m). It is presupposed that, for urban environments, calculating the momentum and scalar fluxes could invoke separate averaging periods, rather than relying on a single prescription (e.g., 30 min). Furthermore, certain characteristics of urban turbulence are found less sensitive to the choice of an averaging period, such as the relationship between the heat-to-momentum transport efficiency and the local stability parameter.

  1. Characterization of carbonaceous species of ambient PM2.5 in Beijing, China

    SciTech Connect

    Fumo Yang; Kebin He; Yongliang Ma

    2005-07-01

    One-week integrated fine particulate matter (i.e., particles {lt}2.5 {mu}m in diameter; PM2.5) samples were collected continuously with a low-flow rate sampler at a downtown site (Chegongzhuang) and a residential site (Tsinghua University) in Beijing between July 1999 and June 2000. The annual average concentrations of organic carbon (OC) and elemental carbon (EC) at the urban site were 23.9 and 8.8 {mu}g m{sup -3}, much higher than those in some cities with serious air pollution. Similar weekly variations of OC and EC concentrations were found for the two sampling sites with higher concentrations in the winter and autumn. The highest weekly variations of OC and EC occurred in the winter, suggesting that combustion sources for space heating were important contributors to carbonaceous particles, along with a significant impact from variable meteorological conditions. High emissions coupled with unfavorable meteorological conditions led to the maximum weekly carbonaceous concentration the week of November 18-25, 1999. The weekly mass ratios of OC:EC ranged between 2 and 4 for most samples and averaged 2.9, probably suggesting that secondary OC (SOC) is present most weeks. The range of contemporary carbon fraction, based on the C14 analyses of eight samples collected in 2001, is 0.330-0.479. Estimated SOC accounted for {approximately}38% of the total OC at the two sites. Average OC and EC concentrations at Tsinghua University were 25% and 18%, respectively, higher than those at Chegongzhuang, which could be attributed to different local emissions of primary carbonaceous particles and gaseous precursors of SOC, as well as different summer photochemical intensities between the two locations. Main carbonaceous sources are from coal combustion, vehicles and cooking. 44 refs., 5 figs., 2 tabs.

  2. Characterizations of volatile organic compounds during high ozone episodes in Beijing, China.

    PubMed

    An, Jun-lin; Wang, Yue-si; Wu, Fang-kun; Zhu, Bin

    2012-04-01

    Air samples were collected in Beijing from June through August 2008, and concentrations of volatile organic compounds (VOCs) in those samples are here discussed. This sampling was performed to increase understanding of the distributions of their compositions, illustrate the overall characteristics of different classes of VOCs, assess the ages of air masses, and apportion sources of VOCs using principal compound analysis/absolute principal component scores (PCA/APCS). During the sampling periods, the relative abundance of the four classes of VOCs as determined by the concentration-based method was different from that determined by the reactivity approach. Alkanes were found to be most abundant (44.3-50.1%) by the concentration-based method, but aromatic compounds were most abundant (38.2-44.5%) by the reactivity approach. Aromatics and alkenes contributed most (73-84%) to the ozone formation potential. Toluene was the most abundant compound (11.8-12.7%) during every sampling period. When the maximum incremental reactivity approach was used, propene, toluene, m,p-xylene, 1-butene, and 1,2,4-trimethylbenzene were the five most abundant compounds during two sampling periods. X/B, T/B, and E/B ratios in this study were lower than those found in other cities, possibly due to the aging of the air mass at this site. Four components were extracted from application of PCA to the data. It was found that the contribution of vehicle exhaust to total VOCs accounted for 53% of VOCs, while emissions due to the solvent use contributed 33% of the total VOCs. Industrial sources contributed 3% and biogenic sources contributed 11%. The results showed that vehicle exhausts (i.e., unburned vehicle emissions + vehicle internal engine combustion) were dominant in VOC emissions during the experimental period. The solvent use made the second most significant contribution to ambient VOCs. PMID:21552987

  3. Characteristics of volatile organic compounds (VOCs) emitted from a petroleum refinery in Beijing, China

    NASA Astrophysics Data System (ADS)

    Wei, Wei; Cheng, Shuiyuan; Li, Guohao; Wang, Gang; Wang, Haiyan

    2014-06-01

    This study made a field VOCs (volatile organic compounds) measurement for a petroleum refinery in Beijing by determining 56 PAMS VOCs, which are demanded for photochemical assessment in US, and obtained the characteristics of VOCs emitted from the whole refinery and from its inner main devices. During the monitoring period, this refinery brought about an average increase of 61 ppbv in the ambient TVOCs (sum of the PAMS VOCs) at the refinery surrounding area, while the background of TVOCs there was only 10-30 ppbv. In chemical profile, the VOCs emitted from the whole refinery was characteristic by isobutane (8.7%), n-butane (7.9%), isopentane (6.3%), n-pentane (4.9%%), n-hexane (7.6%), C6 branched alkanes (6.0%), propene (12.7%), 1-butene (4.1%), benzene (7.8%), and toluene (5.9%). On the other hand, the measurement for the inner 5 devices, catalytic cracking units (CCU2 and CCU3), catalytic reforming unit (CRU), tank farm (TF), and wastewater treatment(WT), revealed the higher level of VOCs pollutions (about several hundred ppbv of TVOCs), and the individual differences in VOCs chemical profiles. Based on the measured speciated VOCs data at the surrounding downwind area, PMF receptor model was applied to identify the VOCs sources in the refinery. Then, coupling with the VOCs chemical profiles measured at the device areas, we concluded that CCU1/3 contributes to 25.9% of the TVOCs at the surrounding downwind area by volume, followed by CCU2 (24.7%), CRU (18.9%), TF (18.3%) and WT (12.0%), which was accordant with the research of US EPA (2008). Finally, ozone formation potentials of the 5 devices were also calculated by MIR technique, which showed that catalytic cracking units, accounting for about 55.6% to photochemical ozone formation, should be given the consideration of VOCs control firstly.

  4. Diurnal and seasonal variation of the PM2.5 apparent particle density in Beijing, China

    NASA Astrophysics Data System (ADS)

    Liu, Zirui; Hu, Bo; Ji, Dongsheng; Wang, Yonghong; Wang, Mingxing; Wang, Yuesi

    2015-11-01

    To characterize the features of particle apparent density and its correlation with chemical composition and meteorological conditions, continuous measurements of particle number size distributions and particle mass concentrations were conducted in the winter and summer periods in Beijing using a Scanning Mobility Particle Sizer and a Tapered Element Oscillating Microbalance with a Filter Dynamic Measurement System. The apparent density, as determined by the particle mass to volume ratios, showed strong seasonal and diurnal variations, with higher values were observed during the warm season (1.60 ± 0.43 g cm-3, July to September 2014) compared to the cold season (1.41 ± 0.40 g cm-3, November 2013 to January 2014). A minimum in the morning and afternoon rush hours was observed in both seasons, representing fresh primary aerosol emissions, which were related to soot particles with low density due to their agglomerate structure, especially observed in the late afternoon hours of the cold season (approximately 1.3 g cm-3) when traffic emissions combined with the coal combustion for heating supply. The highest values were found during midday (approximately 1.8 g cm-3) in the warm season, likely due to increased secondary particle production and the presence of more aged particles with a build-up of the convectively mixed boundary layer. The apparent particle density has the potential to serve as a crude tracer for chemical composition and atmospheric processing and might play an important role when considering the associations between health effects and ambient particles.

  5. An integrated material metabolism model for stocks of urban road system in Beijing, China.

    PubMed

    Guo, Zhen; Hu, Dan; Zhang, Fuhua; Huang, Guolong; Xiao, Qiang

    2014-02-01

    Rapid urbanization has greatly altered the urban metabolism of material and energy. As a significant part of the infrastructure, urban roads are being rapidly developed worldwide. Quantitative analysis of metabolic processes on urban road systems, especially the scale, composition and spatial distribution of their stocks, could help to assess the resource appropriation and potential environmental impacts, as well as improve urban metabolism models. In this paper, an integrated model, which covered all types of roads, intersection structures and ancillary facilities, was built for calculating the material stocks of urban road systems. Based on a bottom-up method, the total stocks were disassembled into a number of stock parts rather than obtained by input-output data, which provided an approach promoting data availability and inner structure understanding. The combination with GIS enabled the model to tackle the complex structures of road networks and avoid double counting. In the case study of Beijing, the following results are shown: 1) The total stocks for the entire road system reached 159 million tons, of which nearly 80% was stored in roads, and 20% in ancillary facilities. 2) Macadam was the largest stock (111 million tons), while stone mastic asphalt, polyurethane plastics, and atactic polypropylene accounted for smaller components of the overall system. 3) The stock per unit area of pedestrian overcrossing was higher than that of the other stock units in the entire system, and its steel stocks reached 0.49 t/m(2), which was 10 times as high as that in interchanges. 4) The high stock areas were mainly distributed in ring-shaped and radial expressways, as well as in major interchanges. 5) Expressways and arterials were excessively emphasized, while minor roads were relatively ignored. However, the variation of cross-sectional thickness in branches and neighborhood roads will have a significant impact on the scale of material stocks in the entire road system

  6. Weekly cycle of magnetic characteristics of PM2.5 and PM2.5-10 in Beijing, China

    NASA Astrophysics Data System (ADS)

    SHI, M.; Wu, H.; Zhang, S.; Li, H.; Yang, T.

    2013-12-01

    In urban areas,fine particle matter with aerodynamic diameter between 2.5 um and 10 um (PM2.5-10), and 2.5 um (PM2.5), as an important source of urban particulate matter (PM) pollutants, have significant negative effects on health, atmospheric visibility and climate. PM has increasingly become a significant index of indicating the atmospheric pollution of city. In recent years, Beijing, China has been listed as one of the most serious air pollution city in the world. In order to investigate the sources of air pollutants, a total of 283 pairs of PM2.5 and PM2.5-10 samples were collected daily from July, 2010 to June, 2011 in Beijing. Mineral magnetic properties and Scanning electron microscope (SEM) observations and energy dispersive X-ray spectroscopy (EDS) analyses of PM2.5 and PM2.5-10 were measured to verify the magnetic materials. Magnetic measures for PM indicated that the major magnetic phase was coarse-grained magnetite-like material. The χlf, χarm, SIRM and χarm/SIRM series of the PM2.5 and PM2.5-10 show seasonal dependences: high values in winter and low values in summer. In additional the parameters analyzed by Time-series methods show a strong cycle about 7 days above 95% confidence level. Weekly cycle of magnetic characteristics of PM2.5 and PM2.5-10 show different pattern: the concentration of magnetic particles in PM2.5-10 show high values in mid-week, and particle sizes is steady, while the concentration of magnetic particles in PM2.5 show reverse a weekly cycle pattern, and particle sizes is smaller in the mid-week.Microscopy analyses reveal basically three morphologies of magnetic grains: aggregate, spherules and angular particles. The ultrafine carbonaceous particles which tend to form complex clusters and chain-like structures, most likely come from coal burning and motor vehicle exhaust. Spherical particles in PM2.5 are dominantly composed of Fe, O and C, grain-diameters of particles range from 0.3 to 2 um. Angular particles of Fe

  7. The possible contribution of the periodic emissions from farmers' activities in the North China Plain to atmospheric water-soluble ions in Beijing

    NASA Astrophysics Data System (ADS)

    Liu, Pengfei; Zhang, Chenglong; Mu, Yujing; Liu, Chengtang; Xue, Chaoyang; Ye, Can; Liu, Junfeng; Zhang, Yuanyuan; Zhang, Hongxing

    2016-08-01

    The North China Plain (NCP), which includes Beijing, is currently suffering from severe haze events due to a high pollution level of PM2.5. To mitigate the serious pollution problem, identification of the sources of PM2.5 is urgently needed for the effective control measures. Daily samples of PM2.5 were collected in Beijing city and in a rural area in Baoding, Hebei Province through the year of 2014, and the seasonal variation of water-soluble ions (WSIs) in PM2.5 was comprehensively analysed to determine their possible sources. The results indicated that the periodic emissions from farmers' activities made a significant contribution to the atmospheric WSIs in Beijing. The relatively high concentration of K+ in winter and autumn at the two sampling sites confirmed that crop straw burning contributed to atmospheric K+ in Beijing. The remarkable elevation of Cl- at the two sampling sites as well as the evident increase of the Cl- / K+ ratio and the Cl- proportion in WSIs during the winter in Beijing could be ascribed to coal combustion for heating by farmers. The unusually high ratio of Cl- to Na+ in summer, the obviously high concentrations of Cl- in the rural sampling site and the elevation of Cl- proportion in WSIs in Beijing during the maize fertilization could be explained by the use of the prevailing fertilizer of NH4Cl in the vast area of NCP. The abnormally high concentrations of Ca2+ at the two sampling sites and the elevation of Ca2+ proportion during the period of the maize harvest and soil ploughing in Beijing provided convincing evidence that the intensive agricultural activities in autumn contributed to the regional mineral dust. The most serious pollution episodes in autumn were coincident with significant elevation of Ca2+, indicating that the mineral dust emission from the harvest and soil ploughing not only increased the atmospheric concentrations of the primary pollutants, but also greatly accelerated formation of sulfate and nitrate through

  8. Atmospheric mercury concentration and chemical speciation at a rural site in Beijing, China: implication of mercury emission sources

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Wang, S. X.; Wang, L.; Hao, J. M.

    2013-05-01

    Continuous measurements of atmospheric mercury concentration and speciation play a key role in identifying mercury sources and its behavior in the atmosphere. In this study, speciated atmospheric mercury including gaseous elemental mercury (GEM), reactive gaseous mercury (RGM) and particle-bound mercury (PBM) were continuously measured at Miyun, a rural site in Beijing, China from December 2008 to November 2009. The average GEM, RGM and PBM concentrations were found to be 3.22 ± 1.74 ng m-3, 10.1 ± 18.8 pg m-3 and 98.2 ± 112.7 pg m-3, respectively, about 2-20 times of the background concentration of Northern Hemisphere. The results indicated that atmospheric mercury concentrations in North China were highly affected by anthropogenic emissions. The atmospheric mercury showed obvious seasonal variations with the highest seasonal average GEM concentration in summer (3.48 ng m-3) and the lowest value in winter (2.66 ng m-3). In autumn and winter a diurnal variation of GEM was observed with peak levels in late afternoon till midnight. Most of the high RGM concentration values occurred in the afternoon of all seasons due to the higher oxidation. The PBM concentration was higher in early morning of all seasons because of the atmospheric stratification during nighttime against laminar fluxes during daytime. The ratio of GEM to CO indicates that residential boilers play an important role in the elevation of GEM in winter. The ratio of RGM to O3 could be an indicator of the contribution of local primary sources. The ratio of PBM to PM2.5 reveals that the air mass from east and southwest to the site in spring and summer carries more atmospheric mercury. The HYSPLIT back-trajectory analysis indicated that the monitoring site is affected by local, regional and interregional sources simultaneously during heavy pollution episodes. The results from the potential source contribution function (PSCF) model indicate that the atmospheric transport predominantly from the northwest

  9. Atmospheric mercury concentration and chemical speciation at a rural site in Beijing, China: implications of mercury emission sources

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Wang, S. X.; Wang, L.; Hao, J. M.

    2013-10-01

    Continuous measurements of atmospheric mercury concentration and speciation play a key role in identifying mercury sources and its behavior in the atmosphere. In this study, speciated atmospheric mercury including gaseous elemental mercury (GEM), reactive gaseous mercury (RGM) and particle-bound mercury (PBM) were continuously measured at Miyun, a rural site in Beijing, China, from December 2008 to November 2009. The average GEM, RGM and PBM concentrations were found to be 3.22 ± 1.74, 10.1 ± 18.8 and 98.2 ± 112.7 pg m-3, respectively, about 2-20 times higher than the background concentration of the Northern Hemisphere. The results indicated that atmospheric mercury concentrations in northern China were highly affected by anthropogenic emissions. The atmospheric mercury showed obvious seasonal variations, with the highest seasonal average GEM concentration in summer (3.48 ng m-3) and the lowest value in winter (2.66 ng m-3). In autumn and winter a diurnal variation of GEM was observed, with peak levels in the late afternoon till midnight. Most of the high RGM concentration values occurred in the afternoon of all seasons due to the higher oxidation. The PBM concentration was higher in early morning of all seasons because of the the temperature inversion that increases in depth as the night proceeds. The ratio of GEM to CO indicates that residential boilers play an important role in the elevation of GEM in winter. The ratio of RGM to O3 could be an indicator of the contribution of local primary sources. The ratio of PBM to PM2.5 reveals that the air mass from the east and southwest of the site in spring and summer carries more atmospheric mercury. The HYSPLIT back-trajectory analysis indicated that the monitoring site is affected by local, regional and interregional sources simultaneously during heavy pollution episodes. The results from the potential source contribution function (PSCF) model indicate that the atmospheric transport predominantly from the northwest

  10. Genomic Characterization of Two Novel HIV-1 Second-Generation Recombinant Forms Among Men Who Have Sex with Men in Beijing, China

    PubMed Central

    Li, Zheng; Wei, Huamian; Feng, Yi; Li, Jia; Kalish, Marcia L.; Lu, Hongyan; Yin, Lu; Liao, Lingjie; Qian, Han-Zhu; Frost, Simon D.W.; Ruan, Yuhua; Vermund, Sten H.; Shao, Yiming

    2015-01-01

    Abstract We report two different unique HIV-1 recombinant viruses from two HIV-positive men who have sex with men (MSM) in Beijing, China. Phylogenetic analysis of near full-length genomes (NFLG) showed that the unique recombinant forms (URFs) were comprised of gene regions from two circulating recombinant forms, CRF01_AE and CRF07_BC, both common in China. The parental CRF01_AE region of the recombinants clustered together with a previously described cluster 4 lineage of CRF01_AE. The CRF07_BC regions of both the recombinants clustered within the CRF07_BC radiation, but were distinct from other CRF07_BC reference sequences. The two recombinant forms had two breakpoints in common. The emergence of the two URFs indicates the ongoing generation of recombinant viruses involving CRF01_AE and CRF07_BC, and may provide insight into our understanding of the dynamics and complexity of the HIV-1 epidemic in China. PMID:25495675