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    题名 作者 年代 出处 被引量
1Controlling N-doping type in carbon to boost single-atom site Cu catalyzed transfer hydrogenation of quinoline显示文摘Single-atom site(SA)catalysts on N-doped carbon(CN)materials exhibit prominent performance for their active sites being M-Nx.Due to the commonly random doping behaviors of N species in these CN,it is a tough issue to finely regulate their doping types and clarify their effect on the catalytic property of such catalysts.Herein,we report that the N-doping type in CN can be dominated as pyrrolic-N and pyridinic-N respectively through compounding with different metal oxides.It is found that the proportion of distinct doped N species in CN depends on the acidity and basicity of compounded metal oxide host.Owing to the coordination by pyrrolic-N,the SA Cu catalyst displays an enhanced activity(two-fold)for transfer hydrogenation of quinoline to access the valuable molecule tetrahydroquinoline with a good selectivity(99%)under mild conditions.The higher electron density of SA Cu species induced by the predominate pyrrolic-N coordination benefits the hydrogen transfer process and reduces the energy barrier of the hydrogenation pathway,which accounts for the improved catalytic effeciency.Jian Zhang Caiyan Zheng Maolin Zhang Yajun Qiu Qi Xu Weng-Chon Cheong Wenxing Chen Lirong Zheng Lin Gu Zhengpeng Hu Dingsheng Wang Yadong Li 2020Nano Research2020,13,11:29
2Trace metals in atmospheric fine particles in one industrial urban city: Spatial variations, sources, and health implications显示文摘Trace metals in PM2.5were measured at one industrial site and one urban site during September, 2010 in Ji'nan, eastern China. Individual aerosol particles and PM2.5samples were collected concurrently at both sites. Mass concentrations of eleven trace metals(i.e., Al, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Sr, Ba, and Pb) and one metalloid(i.e., As) were measured by inductively coupled plasma atomic emission spectroscopy(ICP-AES). The result shows that mass concentrations of PM2.5(130 μg/m3) and trace metals(4.03 μg/m3) at the industrial site were 1.3 times and 1.7 times higher than those at the urban site, respectively, indicating that industrial activities nearby the city can emit trace metals into the surrounding atmosphere. Fe concentrations were the highest among all the measured trace metals at both sites, with concentrations of 1.04 μg/m3at the urban site and 2.41 μg/m3at the industrial site, respectively. In addition, Pb showed the highest enrichment factors at both sites, suggesting the emissions from anthropogenic activities existed around the city. Correlation coefcient analysis and principal component analysis revealed that Cu, Fe, Mn, Pb, and Zn were originated from vehicular trafc and industrial emissions at both sites; As, Cr, and part of Pb from coal-fired power plant; Ba and Ti from natural soil. Based on the transmission electron microscopy analysis, we found that most of the trace metals were internally mixed with secondary sulfate/organic particles. These internally mixed trace metals in the urban air may have diferent toxic abilities compared with externally mixed trace metals.Shengzhen Zhou Qi Yuan Weijun Li Yaling Lu Yangmei Zhang Wenxing Wang 2014Journal of Environmental Sciences2014,26,1:23
3Atomically dispersed Au_1 catalyst towards efficient electrochemical synthesis of ammonia显示文摘Tremendous efforts have been devoted to explore energy-efficient strategies of ammonia synthesis to replace Haber–Bosch process which accounts for 1.4% of the annual energy consumption. In this study,atomically dispersed Au_1 catalyst is synthesized and applied in electrochemical synthesis of ammonia under ambient conditions. A high NH_4^+ Faradaic efficiency of 11.1% achieved by our Au_1 catalyst surpasses most of reported catalysts under comparable conditions. Benefiting from efficient atom utilization, an NH_4^+ yield rate of 1,305 lg h^(-1) mg_(Au)^(-1) has been reached, which is roughly 22.5 times as high as that by supported Au nanoparticles. We also demonstrate that by employing our Au_1 catalyst, NH4+can be electrochemically produced directly from N_2 and H_2 with an energy utilization rate of 4.02 mmol kJ^(-1). Our study provides a possibility of replacing the Haber–Bosch process with environmentally benign and energy-efficient electrochemical strategies.Xiaoqian Wang Wenyu Wang Man Qiao Geng Wu Wenxing Chen Tongwei Yuan Qian Xu Min Chen Yan Zhang Xin Wang Jing Wang Jingjie Ge Xun Hong Yafei Li Yuen Wu Yadong Li 2018Science Bulletin2018,63,19:22
4Impact of emission control on regional air quality: An observational study of air pollutants before, during and after the Beijing Olympic Games显示文摘An observational study on trace gases and PM2.5was conducted at three sites in and around Beijing, during the Olympic season from 2007 to 2009. Air quality improved significantly during the Olympic Games due to the special emission control measures. However, concentrations of the primary pollutants and PM were found to have risen significantly after the Games. Although the major O3precursors(NOx and VOCs) were well controlled during the Olympic season, O3was still found to be the highest in 2008, based on the data of ground-based observation. All this information suggests that while control of regional emissions for the Beijing Olympic Games did improved the air quality in Beijing, more eforts will be needed for the continuous improvement of regional air quality, especially for significant reductions of O3and fine particulate pollution, and not only in Beijing, but also in the Beijing-Tianjin-Hebei region.Shulan Wang Jian Gao Yuechong Zhang Jingqiao Zhang Fahe Cha Tao Wang Chun Ren Wenxing Wang 2014Journal of Environmental Sciences2014,26,1:20
5Porphyrin-like Fe-N4 sites with sulfur adjustment on hierarchical porous carbon for different rate-determining steps in oxygen reduction reaction显示文摘We developed a strategy based on coordination polymer to synthesize singleatom site Fe/N and S-codoped hierarchical porous carbon (Fe1/N,S-PC).The as-obtained Fe1/N,S-PC exhibited superior oxygen reduction reaction (ORR) performance with a half-wave potential (Ev2,0.904 V vs.RHE) that was better than that of commercial Pt/C (E1/2,0.86 V vs.RHE),single-atom site Fe/N-doped hierarchical porous carbon (Fe1/N-PC) without S-doped (E1/2,0.85 V vs.RHE),and many other nonprecious metal catalysts in alkaline medium.Moreover,the Fe1/N,S-PC revealed high methanol tolerance and firm stability.The excellent electrocatalytic activity of Fe1/N,S-PC is attributed to the synergistic effects from the atomically dispersed porphyrin-like Fe-N4 active sites,the heteroatom codoping (N and S),and the hierarchical porous structure in the carbon materials.The calculation based on density functional theory further indicates that the catalytic performance of Fe1/N,S-PC is better than that of Fe1/N-PC owing to the sulfur doping that yielded different rate-determining steps.Konglin Wu Xin Chen Shoujie Liu Yuan Pan Weng-Chon Cheong Wei Zhu Xing Cao Rongan Shen Wenxing Chen Jun LUO Wensheng Yan Lirong Zheng Zheng Chen Dingsheng Wang Qing Peng Chen Chen Yadong Li 2018Nano Research2018,11,12:18
6Application of computational fluid dynamic to model the hydraulic performance of subsurface flow wetlands显示文摘A subsurface flow wetland(SSFW)was simulated using a commercial computational fluid dynamic(CFD)code.The constructed media was simulated using porous media and the liquid resident time distribution(RTD)in the SSFW was obtained using the particle trajectory model.The effect of wetland configuration and operating conditions on the hydraulic performance of the SSFW were investigated.The results indicated that the hydraulic performance of the SSFW was predominantly affected by the wetland configuration.The hydraulic effciency of the SSFW with an inlet at the middle edge of the upper media was 0.584 and the best among the SSFWs with an inlet at the top,the middle,and the bottom edge of the upper media.The constructed media affected the hydraulic performance by the ratio(K)of the upper and lower media resistance.The selection of appropriate media resistance in the protection layer can improve the hydraulic effciency.When the viscous resistance coeffcient of the media in the protection layer changed from 2.315×105 to 1.200×108,the hydraulic effciency of the SSFW increased from 0.301 to 0.751.However,the effect of operating conditions on the hydraulic effciency of the SSFW was slight.Liwei FAN Hai Reti Wenxing WANG Zexiang LU Zhiming YANG 2008Journal of Environmental Sciences2008,20,12:17
7Photochemical pollution in Lanzhou, China - A case study显示文摘The photochemical air pollution in Xigu district of Lanshou city, Gansu Province was studied during a period of 1981-1984. The extremely high NMHC/NOx ratio and ozone level elevation after rain have been noticed. A series of outdoor and indoor reaction chamber simulation experiments conducted in order to understand the specific conditions. The ozone formation under NMHC/NOx condition and the possible reason for high ozone concentration after rain are discussed.Tang Xiaoyan , Li Jinglong, Dong ZhenXing, Wang Yuying,Wang Wenxing , Qi Liwen, Liu Xiling, Zhang Yutian, Zhang Xuejin,Tian Bingshen, Jin Suwen , Yang Lingqing and Zhang Yixin Department of Technical Physics,Peking University, Beijing, China. Chinese Reaearch Academy of Eavironmental Sciences, Beijing,China. Gansu Provincial Environmental Research Institute, Lanshou, China. Lanshou Petrochemical Engineering Institute, Lanshou, China. 1989Journal of Environmental Sciences1989,1,1:15
8Particle number size distribution and new particle formation:New characteristics during the special pollution control period in Beijing显示文摘New particle formation is a key process in shaping the size distribution of aerosols in the atmosphere.We present here the measurement results of number and size distribution of aerosol particles (10-10000 nm in diameter) obtained in the summer of 2008,at a suburban site in Beijing,China.We firstly reported the pollution level,particle number size distribution,diurnal variation of the particle number size distribution and then introduced the characteristics of the particle formation processes.The results showed that the number concentration of ultrafine particles was much lower than the values measured in other urban or suburban areas in previous studies.Sharp increases of ultrafine particle count were frequently observed at noon.An examination of the diurnal pattern suggested that the burst of ultrafine particles was mainly due to new particle formation promoted by photochemical processes.In addition,high relative humidity was a key factor driving the growth of the particles in the afternoon.During the 2-month observations,new particle formation from homogeneous nucleation was observed for 42.7% of the study period.The average growth rate of newly formed particles was 3.2 nm/hr,and varied from 1.2 to 8.0 nm/hr.The required concentration of condensable vapor was 4.4×10 7 cm-3,and its source rate was 1.2×10 6 cm-3 sec-1.Further calculation on the source rate of sulphuric acid vapor indicated that the average participation of sulphuric acid to particle growth rates was 28.7%.Jian Gao Fahe Chai Tao Wang Shulan Wang Wenxing Wang 2012Journal of Environmental Sciences2012,24,1:14
9Role of farnesoid X receptor and bile acids in alcoholic liver disease显示文摘Alcoholic liver disease(ALD) is one of the major causes of liver morbidity and mortality worldwide. Chronic alcohol consumption leads to development of liver pathogenesis encompassing steatosis, inflammation, fibrosis, cirrhosis, and in extreme cases, hepatocellular carcinoma. Moreover,ALD may also associate with cholestasis. Emerging evidence now suggests that farnesoid X receptor(FXR) and bile acids also play important roles in ALD. In this review, we discuss the effects of alcohol consumption on FXR, bile acids and gut microbiome as well as their impacts on ALD. Moreover, we summarize the findings on FXR, Fox O3a(forkhead box-containing protein class O3a) and PPARα(peroxisome proliferator-activated receptor alpha) in regulation of autophagy-related gene transcription program and liver injury in response to alcohol exposure.Sharon Manley Wenxing Ding 2015Acta Pharmaceutica Sinica B2015,5,2:12
10X-ray-charged bright persistent luminescence in NaYF_(4):Ln^(3+)@NaYF_(4) nanoparticles for multidimensional optical information storage显示文摘NaYF_(4):Ln^(3+),due to its outstanding upconversion characteristics,has become one of the most important luminescent nanomaterials in biological imaging,optical information storage,and anticounterfeiting applications.However,the large specific surface area of NaYF_(4):Ln^(3+)nanoparticles generally leads to serious nonradiative transitions,which may greatly hinder the discovery of new optical functionality with promising applications.In this paper,we report that monodispersed nanoscale NaYF_(4):Ln^(3+),unexpectedly,can also be an excellent persistent luminescent(PersL)material.The NaYF_(4):Ln^(3+)nanoparticles with surface-passivated core–shell structures exhibit intense X-ray-charged PersL and narrow-band emissions tunable from 480 to 1060 nm.A mechanism for PersL in NaYF_(4):Ln^(3+)is proposed by means of thermoluminescence measurements and host-referred binding energy(HRBE)scheme,which suggests that some lanthanide ions(such as Tb)may also act as effective electron traps to achieve intense PersL.The uniform and spherical NaYF_(4):Ln^(3+)nanoparticles are dispersible in solvents,thus enabling many applications that are not accessible for traditional PersL phosphors.A new 3-dimensional(2 dimensions of planar space and 1 dimension of wavelength)optical information-storage application is demonstrated by inkjet-printing multicolor PersL nanoparticles.The multicolor persistent luminescence,as an emerging and promising emissive mode in NaYF_(4):Ln^(3+),will provide great opportunities for nanomaterials to be applied to a wider range of fields.Yixi Zhuang Dunrong Chen Wenjing Chen Wenxing Zhang Xin Su Renren Deng Zhongfu An Hongmin Chen Rong-Jun Xie 2021Light(Science & Applications)2021,10,7:12
11Particle number size distribution and new particle formation (NPF) in Lanzhou,Western China显示文摘Particle number size distribution from 10 to 10,000 nm was measured by a wide-range particle spectrometer (WPS-1000XP) at a downwind site north of downtown Lanzhou, western China, from 25 June to 19 July 2006. We first report the pollution level, diurnal variation of particle concentration in different size ranges and then introduce the characteristics of the particle formation processes, to show that the number concentration of ultrafine particles was lower than the values measured in other urban or suburban areas in previous studies. However, the fraction of ultrafine particles in total aerosol number concentration was found to be much higher. Furthermore, sharp increase of ultrafine particle concentration was frequently observed at noon. An examination of the diurnal pattern suggests that the burst of the ultrafine particles was mainly due to nucleation process. During the 25-day observation, new particle formation (NPF) from homogeneous nucleation was observed during 33% of the study period. The average growth rate of the newly formed particles was 4.4 nm/h, varying from 1.3 to 16.9 nm/h. The needed concentration of condensable vapor was 6.1 × 107 cmfi3, and its source rate was 1.1 × 106 cmfi3 sfi1. Further calculation on the source rate of sulphuric acid vapor indicated that the average participation of sulphuric acid to particle growth rate was 68.3%.Jian Gao Fahe Chai Tao Wang Wenxing Wang 2011Particuology2011,9,6:12
12Method for Evaluating the Degrees of Land Use Sustainability of Mountainous County and its Application in Yunnan Province,China显示文摘The evaluation of sustainable land use is the key issue in the field of studying the sustainable land utilization. In general analysis, the sustainable land use is evaluated respectively from its ecological sustainability, economic sustainability and social sustainability in China and other countries in recent years. Although this evaluation is an important work, it seems insufficient and hard to comprehensively reflect the whole degree of land use sustainability. Thus, to make up this deficiency, this paper brings forward the evaluation indexes, which make it possible to quantitatively reflect the whole degree of land use sustainability, namely, the concept of 'degrees of overall land use sustainability' (DOS), and research and development of the method of measurement and calculation in DOS. Taking the evaluation of the degree of land use sustainability in county regions of Yunnan Province as the actual example for analysis, results are basically as follows:1) The degree of land use sustainability (DOS) is the ration index to organically and systematically integrate the degree of ecological friendliness (DEF), the degree of economic viability (DEV) and the degree of social acceptability (DSA), able to comprehensively reflect the whole sustainability degree of regional land use. 2) Based on the value of DOS, the grading system and standard for the sustainability of land use may be established and totally divided into five grades, namely, the high-degree sustainability, middle-degree sustainability, low-degree sustainability, conditional sustainability and non-sustainability. Meanwhile, the standard for distinguishing sustainability grades has also been confirmed so as to determine the nature of sustainability degrees in different grades. This makes the possibility for the combination of nature determination with ration in research result and provides with the scientific guideline and decision-making gist for better implementation of sustainable land use strategy.3) The practice in evaluation of sustainability degree in county regional land use in Yunnan shows that the value of the degree of land use sustainability (DOS) of whole Yunnan Province is only 58.39, belonging to the grade of low-degree sustainability. Two thirds of counties in the whole province represent the grade of 'conditional sustainability' and 'non-sustainability' in the sustainability of land use. Among these counties, 11.11 % shows 'non- sustainability'. The lowest degree of land use sustainability appears especially in the middle plateau mountain region of Northeast Yunnan, where the value of DOS in most counties (districts) is below 40 %, belonging to the grade of 'non-sustainability'. The sustainability degree in the karst mountainous region in lower-middle plateau mountain region in Southeast Yunnan is generally low and the value of sustainability degree (DOS) in most of the counties (cities and districts) is below 55. The value of sustainability degree (DOS) in most of the counties (cities and districts) in the north, west, northwest and southwest parts of Yunnan is below 55. This article also analyzes the reasons of low degree of sustainability in land use in Yunnan and puts forward the countermeasures to increase the degree of sustainability in land use in the whole province.YANG Zisheng LIU Yansui TAO Wenxing XU Jingling ZHAO Qiaogui 2008Journal of Mountain Science2008,5,2:10
13Understanding unusually high levels of peroxyacetyl nitrate(PAN) in winter in Urban Jinan,China显示文摘Peroxyacetyl nitrate(PAN), as a major secondary pollutant, has gained increasing worldwide attentions, but relevant studies in China are still quite limited. During winter of 2015 to summer of 2016, the ambient levels of PAN were measured continuously by an automatic gas chromatograph equipped with an electron capture detector(GC–ECD) analyzer at an urban site in Jinan(China), with related parameters including concentrations of O3, NO, NO_2, PM_(2.5), HONO,the photolysis rate constant of NO_2 and meteorological factors observed concurrently. The mean and maximum values of PAN concentration were(1.89 ± 1.42) and 9.61 ppbv respectively in winter, and(2.54 ± 1.44) and 13.47 ppbv respectively in summer. Unusually high levels of PAN were observed during severe haze episodes in winter, and the formation mechanisms of them were emphatically discussed. Study showed that high levels of PAN in winter were mainly caused by local accumulation and strong photochemical reactions during haze episodes, while mass transport played only a minor role. Accelerated photochemical reactions(compared to winter days without haze) during haze episodes were deduced by the higher concentrations but shorter lifetimes of PAN, which was further supported by the sufficient solar radiation in the photolysis band along with the high concentrations of precursors(NO_2, VOCs) and HONO during haze episodes. In addition, significant PAN accumulation during calm weather of haze episodes was verified by meteorological data.Lu Liu Xinfeng Wang Jianmin Chen Likun Xue Wenxing Wang Liang Wen Dandan Li Tianshu Chen 2018Journal of Environmental Sciences2018,30,9:10
14The Arabidopsis P450 protein CYP82C2 modulates jasmonateinduced root growth inhibition, defense gene expression and indole glucosinolate biosynthesis显示文摘Jasmonic 酸(JA ) 是对草食动物和一些微生物引起的病原体调整大量植物防卫回答的一个丰满的导出酸的发信号分子。分子的基因研究证实了 JA 也在植物开发的几个方面执行一个关键角色。这里,我们描述 Arabidopsis 变异的 jasmonic acid-hypersensitive1-1 (jah1-1 ) 的描述,它在 JA 回答的几个方面是有缺点的。尽管异种在根生长抑制展出增加的敏感到 JA,它显示出 JA 可诱导的防卫基因和减少的抵抗的减少的表示到 necrotrophic 真菌 Botrytis cinerea。基因克隆研究显示这些缺点被一个变化在细胞色素 P450 蛋白质 CYP82C2 引起。我们提供证明的证据到 B 的 jah1-1 异种的损害抵抗。cinerea 被导致 JA 的防卫基因的减少的表示伴随并且减少了导致 JA 的吲哚 glucosinolates (IG ) 的累积。相反地,提高的抵抗到 B。在 CYP82C2-overexpressing 植物的 cinerea 被导致 JA 的防卫基因的增加的表示伴随并且提高了导致 JA 的 IG 的层次。我们证明 CYP82C2 影响 IG biosynthetic 先锋的导致 JA 的累积色氨酸(Trp ) ,然而并非导致 JA 的 IAA 或导致病原体的 camalexin。一起,我们 CYP82C2 可以在导出 Trp 的第二等的代谢物的新陈代谢扮演在下面的一个假设在 JA 在哪个铺平调节的结果支持被提高。jah1-1 异种应该因此在向理解位于调停 JA 的微分回答的复杂性下面的机制的未来研究是重要的,它是重要的让植物使他们的生长适应千变万化环境。Fang Liu Hongling Jiang Songqing Ye Wen-Ping Chen Wenxing Liang Yingxiu Xu Bo Sun Jiaqiang Sun Qiaomei Wang Jerry D Cohen Chuanyou Li 2010Cell Research2010,20,5:10
15Population Genomic Analysis and De Novo Assembly Reveal the Origin of Weedy Rice as an Evolutionary Game显示文摘Crop weediness,especially that of weedy rice(Oryza sativa f.spontanea),remains mysterious.Weedy rice possesses robust ecological adaptability;however,how this strain originated and gradually formed proprietary genetic features remains unclear?Here,we demonstrate that weedy rice at Asian high latitudes(WRAH)is phylogenetically well defined and possesses unselected genomic characteristics in many divergence regions between weedy and cultivated rice.We also identified novel quantitative trait loci underlying weedy-specific traits,and revealed that a genome block on the end of chromosome 1 is associated with rice weediness.To identify the genomic modifications underlying weedy rice evolution,we generated the first de novo assembly of a high-quality weedy rice genome(WR04-6),and conducted a comparative genomics study between WR04-6 with other rice reference genomes.Multiple lines of evidence,including the results of demographic scenario comparisons,suggest that differentiation between weedy rice and cultivated rice was initiated by genetic improvement of cultivated rice and that the essence of weediness arose through semi-domestication.A plant height model further implied that the origin of WRAH can be modeled as an evolutionary game and indicated that strategy-based selection driven by fitness shaped its genomic diversity.Jian Sun Dianrong Ma Liang Tang Minghui Zhao Guangchen Zhangh Wenjia Wang Jiayu Song Xiang Li Zimeng Liu Wenxing Zhang Quan Xu Yuncheng Zhou Jianzhong Wu Toshio Yamamoto Fei Dai Yan Lei Song Li Gang Zhou Hongkun Zheng Zhengjin Xu Wenfu Chen 2019Molecular Plant2019,12,5:9
16Phylogenetic and genetic characterization of a 2017 clinical isolate of H7N9 virus in Guangzhou,China during the fifth epidemic wave显示文摘Pathogenic H7N9 influenza viruses continue to pose a public health concern. The H7N9 virus has caused five outbreak waves of human infections in China since 2013. In the present study, a novel H7N9 strain(A/Guangdong/8 H324/2017) was isolated from a female patient with severe respiratory illness during the fifth wave of the 2017 H7N9 epidemic. Phylogenetic analysis showed that the H7N9 viruses collected during the fifth wave belong to two different lineages: the Pearl River Delta lineage and the Yangtze River Delta lineage. The novel isolate is closely related to the Pearl River Delta H7N9 viruses, which were isolated from patients in Guangdong Province. The novel H7N9 isolate has an insertion of three basic amino acids in the cleavage site of hemagglutinin(HA), which may enhance virulence in poultry. The 2017 isolate also possesses an R292 K substitution in the neuraminidase(NA)protein, which confers oseltamivir resistance. This study highlights the pandemic potential of the novel H7N9 virus in mammals;thus, future characterization and surveillance is warranted.Yongqiang Deng Chunlin Li Jianfeng Han Yingfen Wen Jian Wang Wenxing Hong Xiaofeng Li Zhongyu Liu Qing Ye Jing Li Changshuai Zhou Lei Yu Chengfeng Qin Fuchun Zhang Tao Jiang 2017Science China(Life Sciences)2017,60,12:9
17ANALYSIS OF COLUMN-INTEGRATED AEROSOL OPTICAL THICKNESS IN BEIJING FROM AERONET OBSERVATIONS显示文摘Aerosol Optical Thickness (AOT), water vapor content and derived Angstrom exponent acquired by a CIMEL sun photometer in Beijing are analyzed. Monthly means computed from quality-assured daily means, seasonal trends and inter-annual variations are presented and discussed. Summer has the highest seasonal average AOT at 440 nm (τa440), Angstrom exponent (α440–870) and water vapor content with the values 0.93, 1.34 and 3.0 cm, respectively. The second highest seasonal average τa440 appears in spring with the largest variation of α440–870 and minimum α440–870 0.99 due to the impact of coarse particles. The minimum seasonal average τa440 (0.44) and water vapor content (0.4 cm) appear in winter. The annual average τa440, α440–870 and water vapor content for about 4-year observation period are 0.70, 1.19 and 1.4 cm, respectively. All monthly average Angstrom exponents are within 0.8-1.4, which indicates aerosol in Beijing is a very complex mixture of both fine- and coarse-mode particles (from anthropogenic influence and natural mineral dust).Xuehua Fan Hongbin Chen Philippe Goloub Xiang'ao Xia Wenxing Zhang Bernadette Chatenet 2006China Particuology2006,4,6:9
18Ground-based measurements of aerosol optical properties and radiative forcing in North China显示文摘In order to gain an insight into the aerosol properties and their climatic effect over the continental source regions of China, it is of significance to carry out long-term ground-based measurements of aerosol optical properties and radiative forcing. A couple of temporary and permanent Aerosol Robotic Network (AERONET) sites and three comprehensive radiative sites were established in China as a result of international cooperation in recent years. Heavy aerosol loading and significant temporal and spatial variation over North China are revealed by the AERONET data. Aerosol-induced reductions in surface radiation budget are examined on the basis of collocated observations by sun photometers and pyranometers.Hongbin Chen Xiangao Xia Pucai Wang Wenxing Zhang 2007China Particuology2007,5,3:8
19Photocatalytic oxidation of phenol in aqueous solutions with oxygen catalyzed by supported metallophthalocyanine catalyst显示文摘In this paper, zinc tetraaminophthalocyanine (Zn-APc) was immobilized on cellulosic fiber by covalent bond to obtain a novel cellulosic fiber supported metallophthalocyanine, named Zn-TDTAPc-F. At pH 11, upon visible light irradiation for 6 h in the presence of O2, Zn-TDTAPc-F was found to be highly effective for the degradation of phenol in aqueous solution, and the degradation rate of phenol was more than 95%. HPLC was used to confirm formic acid, fumaric acid and maleic acid as its main degradation products.CHEN WenXing CHEN ShiLiang LüShenShui YAO YuYuan XU MinHong 2007Science China Chemistry2007,50,3:8
20Size Distributions of Aerosol Sulfates and Nitrates in Beijing during the 2008 Olympic Games: Impacts of Pollution Control Measures and Regional Transport显示文摘为 2008 个奥运会,激烈的控制措施在二氧化物(SO2 ) ,氮氧化物(没有 x ) 和处理穷人的问题的另外的污染物质通风的硫的工业、城市的排出物上被实现在北京的质量。在微粒硫酸盐和硝酸盐集中以及他们的尺寸分布上调查 SO2 和没有 x 减小的效果,分离尺寸的喷雾器样品在照原尺寸的控制前后在北京在城市、顺风的农村地点用微孔的一致存款 impactors (MOUDI ) 被收集。在采样时期期间,在城市、农村的地点的好粒子(PM1.8 ) 的集体集中分别地是 94.0 和 85.9 g m3。超过 90% 硫酸盐和 60% 硝酸盐形成了同样好的粒子。得益于有益的气象学的条件和来源控制,硫酸盐在奥林匹克期间在相当低的集中并且首先在冷凝作用模式被观察。控制措施的效果独立被分析让北风和南方的 air-mass-dominated 天说明任何偏爱。在控制措施被实现以后,当在北方的空气群众占优势时,下午,硫酸盐,和硝酸盐显著地被减少,与在更大的粒子的减小的一个更高的百分比。在控制措施被实现以后,微滴模式粒子,在控制被实现以前,统治了硫酸盐和硝酸盐,显著地在集体集中被减少。但当弄脏的南方的空气群众占优势时,本地来源控制在北京测量,有效地没从北方中国平原由于庞大的地区性的贡献减少周围的硫酸盐集中。WANG Xinfeng WANG Tao Ravi Kant PATHAK Mattias HALLQUIST GAO Xiaomeit NIE Wei XUE Likun GAO Jian GAO Rui ZHANG Qingzhu WANG Wenxing WANG Shulan CHAI Fahe CHEN Yizhen 2013Advances in Atmospheric Sciences2013,30,2:8
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