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| 1 | Chemical characteristics of size-resolved aerosols in winter in Beijing显示文摘Size-resolved aerosols were continuously collected by a Nano Sampler for 13 days at an urban site in Beijing during winter 2012 to measure the chemical composition of ambient aerosol particles. Data collected by the Nano Sampler and an ACSM(Aerodyne Aerosol Chemical Speciation Monitor) were compared. Between the data sets,similar trends and strong correlations were observed,demonstrating the validity of the Nano Sampler. PM10 and PM2.5concentrations during the measurement were 150.5 ± 96.0 μg/m3(mean ± standard variation)and 106.9 ± 71.6 μg/m3,respectively. The PM2.5/PM10 ratio was 0.70 ± 0.10,indicating that PM2.5dominated PM10. The aerosol size distributions showed that three size bins of 0.5–1,1–2.5 and 2.5–10 μm contributed 21.8%,23.3% and 26.0% to the total mass concentration(TMC),respectively. OM(organic matter) and SIA(secondary ionic aerosol,mainly SO42-,NO3-and NH4+) were major components of PM2.5. Secondary compounds(SIA and secondary organic carbon) accounted for half of TMC(about 49.8%) in PM2.5,and suggested that secondary aerosols significantly contributed to the serious particulate matter pollution observed in winter. Coal burning,biomass combustion,vehicle emissions and SIA were found to be the main sources of PM2.5. Mass concentrations of water-soluble ions and undetected materials,as well as their fractions in TMC,strikingly increased with deteriorating particle pollution conditions,while OM and EC(elemental carbon) exhibited different variations,with mass concentrations slightly increasing but fractions in TMC decreasing. | Kang Sun Yu Qu Qiong Wu Tingting Han Jianwei Gu Jingjing Zhao Yele Sun Qi Jiang Ziqi Gao Min Hu Yuanhang Zhang Keding Lu Stephan Nordmann Yafang Cheng Li Hou Hui Ge Masami Furuuchi Mitsuhiko Hata Xingang Liu | 2014 | Journal of Environmental Sciences2014，26，8： | 9 |
| 2 | Daytime HONO formation in the suburban area of the megacity Beijing, China显示文摘Nitrous acid(HONO),as a primary precursor of OH radicals,has been considered one of the most important nitrogencontaining species in the atmosphere.Up to 30%of primary OH radical production is attributed to the photolysis of HONO.However,the major HONO formation mechanisms are still under discussion.During the Campaigns of Air Quality Research in Beijing and Surrounding Region(CAREBeijing2006)campaign,comprehensive measurements were carried out in the megacity Beijing,where the chemical budget of HONO was fully constrained.The average diurnal HONO concentration varied from 0.33 to 1.2 ppbv.The net OH production rate from HONO,POH(HONO)net,was on average(from 05:00 to 19:00)7.1×106 molecule/(cm3 s),2.7 times higher than from O3 photolysis.This production rate demonstrates the important role of HONO in the atmospheric chemistry of megacity Beijing.An unknown HONO source(Punknown)with an average of 7.3×106molecule/(cm3 s)was derived from the budget analysis during daytime.Punknown provided four times more HONO than the reaction of NO with OH did.The diurnal variation of Punknown showed an apparent photo-enhanced feature with a maximum around 12:00,which was consistent with previous studies at forest and rural sites.Laboratory studies proposed new mechanisms to recruit NO2 and J(NO2)in order to explain a photo-enhancement of of Punknown.In this study,these mechanisms were validated against the observation-constraint Punknown.The reaction of exited NO2 accounted for only 6%of Punknown,and Punknown poorly correlated with[NO2](R=0.26)and J(NO2)[NO2](R=0.35).These results challenged the role of NO2 as a major precursor of the missing HONO source. | YANG Qiang SU Hang LI Xin CHENG YaFang LU KeDing CHENG Peng GU JianWei GUO Song HU Min ZENG LiMin ZHU Tong ZHANG YuanHang | 2014 | Science China Chemistry2014，57，7： | 8 |
| 3 | An online monitoring system for atmospheric nitrous acid(HONO) based on stripping coil and ion chromatography显示文摘A new instrument for measuring atmospheric nitrous acid(HONO) was developed,consisting of a double-wall glass stripping coil sampler coupled with ion chromatography(SC-IC).SC-IC is featured by small size(50 × 35 × 25 cm) and modular construction,including three independent parts:the sampling unit,the transfer and supporting unit,and the detection unit.High collection efficiency(> 99%) was achieved with 25 μmol/L Na2CO3 as absorption solution even in the presence of highly acidic compounds.This instrument has a detection limit of 8 pptv at 15 min time resolution,with a measurement uncertainty of 7%.Potential interferences from NOx,NO2+SO2,NO2+VOCs,HONO+O3,HNO3,peroxyacetyl nitrite(PAN) and particle nitrite were quantified in laboratory studies and were found to be insignificant under typical atmospheric conditions.Within the framework of the 3C-STAR project,inter-comparison between the SC-IC and LOPAP(long path liquid absorption photometer) was conducted at a rural site in the Pearl River Delta.Good agreement was achieved between the two instruments over three weeks.Both instruments determined a clear diurnal profile of ambient HONO concentrations from 0.1 to 2.5 ppbv.However,deviations were found for low ambient HONO concentrations(i.e.< 0.3 ppbv),which cannot be explained by previous investigated interference species.To accurately determine the HONO budget under illuminated conditions,more intercomparison of HONO measurement techniques is still needed in future studies,especially at low HONO concentrations. | Peng Cheng Yafang Cheng Keding Lu Hang Su Qiang Yang Yikan Zou Yanran Zhao Huabing Dong Limin Zeng Yuanhang Zhang | 2013 | Journal of Environmental Sciences2013，25，5： | 5 |
| 4 | Effect of Mo content on microstructure and stress-rupture properties of a Ni-base single crystal superalloy显示文摘The additional 1.5 wt% Mo was added in a Ni-base single crystal(SC) alloy with the composition of Ni–6.5Al–8.0Mo–2.4Cr–6.2Ta–4.9Co–1.5Re–(0.01–0.05)Y(wt%) to study the effect of Mo content on the microstructure and stress-rupture properties. The creep and stress-rupture tests under the conditions of 850 °C/500 MPa and 1100 °C/130 MPa were conducted, and the microstructure of as-cast, heat treated and stress ruptured specimens were analyzed. It was found that the 1.5 wt% Mo addition enhanced the stress-rupture lives at both intermediate(850 °C) and high(1100 °C)temperatures. The microstructure analysis showed that adding 1.5 wt% Mo in the basic alloy affected the microstructure dramatically, i.e., the Mo-rich phases formed in the specimens of as-cast and stress-ruptured specimens. It is considered that the improvement of the stress-rupture lives is duo to the strengthening effect of Mo to both γ and γ'phases and the decrease of stacking fault energy, diffusion constant and dislocation spacing. The Mo-rich phases precipitated under condition of 1100 °C/130 MPa did not affect the creep and stress-rupture properties obviously in the present study. | Yunfei Liang Shusuo Li Cheng Ai Yafang Han Shengkai Gong | 2016 | Progress in Natural Science:Materials International2016，26，1： | 5 |
| 5 | Influences of relative humidity and particle chemical composition on aerosol scattering properties during the 2006 PRD campaign 显示文摘 | Liu Xingang Cheng Yafang Zhang Yuanhang | 2008 | Atmospheric Environment2008，42，7： | 1 |
| 6 | Aerosol number size distribution and new particle formation at a rural/coastal site in Pearl River Delta (PRD) of China显示文摘 | Shang Liu Min Hu Zhijun Wu Birgit Wehner Alfred Wiedensohler Yafang Cheng | 2008 | Atmospheric Environment2008，，25： | 1 |
| 7 | microRNA-128 plays a critical role in human non-small cell lung cancer tumourigenesis, angiogenesis and lymphangiogenesis by directly targeting vascular endothelial growth factor-C显示文摘 | Jing Hu Yongxia Cheng Yuezhen Li Zaishun Jin Yanming Pan Guibo Liu Songbin Fu Yafang Zhang Kejian Feng Yukuan Feng | 2014 | European Journal of Cancer2014，，13： | 1 |
| 8 | Distinct lung microbial community states in patients with pulmonary tuberculosis显示文摘An improved understanding of the lung microbiome may lead to better strategies to diagnose, treat, and prevent pulmonary tuberculosis (PTB). However, the characteristics of the lung microbiomes of patients with TB remain largely undefined. In this study, 163 bronchoalveolar lavage (BAL) samples were collected from 163 sputum-negative suspected PTB patients. Furthermore, 12 paired BAL samples were obtained from 12 Mycobacterium tuberculosis-positive (MTB+) patients before and after negative conversion following a two-month anti-TB treatment. The V3–V4 region of the 16S ribosomal RNA (rRNA) gene was used to characterize the microbial composition of the lungs. The results showed that the prevalence of MTB in the BAL samples was 42.9% (70/163) among the sputum-negative patients. The α-diversity of lung microbiota was significantly less diverse in MTB+ patients compared with Mycobacterium tuberculosis-negative (MTB–) patients. There was a significant difference in β-diversity between MTB+ and MTB– patients. MTB+ patients were enriched with Anoxybacillus, while MTB– patients were enriched with Prevotella, Alloprevotella, Veillonella, and Gemella. There was no significant difference between the Anoxybacillus detection rates of MTB+ and MTB– patients. The paired comparison between the BAL samples from MTB+ patients and their negative conversion showed that BAL negative-conversion microbiota had a higher α-diversity. In conclusion, distinct features of airway microbiota could be identified between samples from patients with and without MTB. Our results imply links between lung microbiota and different clinical groups of active PTB. | Yongfeng Hu Ying Kang Xi Liu Min Cheng Jie Dong Lilian Sun Yafang Zhu Xianwen Ren Qianting Yang Xinchun Chen Qi Jin Fan Yang | 2020 | Science China(Life Sciences)2020，63，10： | 1 |
| 9 | Aerosol hygroscopicity and its impact on atmospheric visibility and radiative forcing in Guangzhou during the 2006 PRIDE-PRD campaign 显示文摘 | LIU Xingang ZHANG Yuanhang CHENG Yafang | 2012 | Atmospheric Environment2012，60，： | 1 |
| 10 | Influences of relative humidity and particle chemical composition on aerosol scattering properties during the 2006 PRD campaign 显示文摘 | LIU Xingang CHENG Yafang ZHANG Yuanhang | 2008 | Atmos Environ2008，42，： | 1 |
| 11 | Aerosol hygroscopicity and its impact on atmospheric visibility and radiative forcing in Guangzhou during the 2006 PRIDE-PRD campaign显示文摘 | Xingang Liu Yuanhang Zhang Yafang Cheng Min Hu Tingting Han | 2012 | Atmospheric Environment2012，，： | 1 |
| 12 | Influences of relative humidity and particle chemical composition on aerosol scattering properties during the 2006 PRD campaign显示文摘 | Xingang Liu Yafang Cheng Yuanhang Zhang Jinsang Jung Nobuo Sugimoto Shih-Yu Chang Young J. Kim Shaojia Fan Limin Zeng | 2007 | Atmospheric Environment2007，，7： | 1 |
| 13 | Influences of relative humidity and particle chemical composition on aerosol scattering properties during the 2006 PRD campaign 显示文摘 | LIU Xingang CHENG Yafang ZHANG Yuanhang | 2008 | Amaospheric Environment2008，42，： | 1 |
| 14 | Natural products for infectious microbes and diseases:an overview of sources,compounds,and chemical diversities显示文摘As coronavirus disease 2019(COVID-19) threatens human health globally,infectious disorders have become one of the most challenging problem for the medical community.Natural products(NP) have been a prolific source of antimicrobial agents with widely divergent structures and a range of vast biological activities.A dataset comprising 618 articles,including 646 NP-based compounds from 672 species of natural sources with biological activities against 21 infectious pathogens from five categories,was assembled through manual selection of published articles.These data were used to identify 268 NP-based compounds classified into ten groups,which were used for network pharmacology analysis to capture the most promising lead-compounds such as agelasine D,dicumarol,dihydroartemisinin and pyridomycin.The distribution of maximum Tanimoto scores indicated that compounds which inhibited parasites exhibited low diversity,whereas the chemistries inhibiting bacteria,fungi,and viruses showed more structural diversity.A total of 331 species of medicinal plants with compounds exhibiting antimicrobial activities were selected to classify the family sources.The family Asteraceae possesses various compounds against C.neoformans,the family Anacardiaceae has compounds against Salmonella typhi,the family Cucurbitacea against the human immunodeficiency virus(HIV),and the family Ancistrocladaceae against Plasmodium.This review summarizes currently available data on NPbased antimicrobials against refractory infections to provide information for further discovery of drugs and synthetic strategies for anti-infectious agents. | Lu Luo Jun Yang Cheng Wang Jie Wu Yafang Li Xu Zhang Hui Li Hui Zhang Yumei Zhou Aiping Lu Shilin Chen | 2022 | Science China(Life Sciences)2022，65，6： | 1 |
| 15 | Effect of Salvianolic-acid B on inhibiting MAPK signaling induced by transforming growth factor-β1 in activated rat hepatic stellate cells显示文摘 | Zhigang Lv Yafang Song Dongying Xue Wenwei Zhang Yang Cheng Lieming Xu | 2010 | Journal of Ethnopharmacology2010，，2： | 1 |
| 16 | Pharmacokinetics of propafenone hydrochloride sustained-release capsules in male beagle dogs显示文摘This paper describes the development and validation of a liquid chromatography–mass spectrometric assay for propafenone and its application to a pharmacokinetic study of propafenone administered as a new propafenone hydrochloride sustained-release capsule(SR-test), as an instant-release tablet(IR-reference) and as the market leader sustained-release capsule(Rythmol, SR-reference) in male beagle dogs(n ? 8). In Study A comparing SR-test with IR-reference in a crossover design T_(max) and t_(1/2) of propafenone for SR-test were significantly higher than those for IR-reference while C_(max) and AUC were lower demonstrating the sustained release properties of the new formulation. In Study B comparing SRtest with SR-reference the observed C_(max) and AUC of propafenone for SR-test(124.57140.0 ng/m L and612.07699.2 ng·h/m L, respectively) were higher than for SR-reference(78.52772.92 ng/m L and423.67431.6 ng·h/m L, respectively) although the differences were not significant. Overall, the new formulation has as good if not better sustained release characteristics to the market leader formulation. | Liping Pan Yafang Qian Minlu Cheng Pan Gu Yanna He Xiaowen Xu Li Ding | 2015 | Acta Pharmaceutica Sinica B2015，5，1： | 1 |
| 17 | Exploring HONO formation and its role in driving secondary pollutants formation during winter in the North China Plain显示文摘Daytime HONO photolysis is an important source of atmospheric hydroxyl radicals(OH).Knowledge of HONO formation chemistry under typical haze conditions,however,is still limited.In the Multiphase chemistry experiment in Fogs and Aerosols in the North China Plain in 2018,we investigated the wintertime HONO formation and its atmospheric implications at a rural site Gucheng.Three different episodes based on atmospheric aerosol loading levels were classified:clean periods(CPs),moderately polluted periods(MPPs)and severely polluted periods(SPPs).Correlation analysis revealed that HONO formation via heteroge.neous conversion of NO_(2)was more efficient on aerosol surfaces than on ground,highlighting the important role of aerosols in promoting HONO formation.Daytime HONO budget analysis indicated a large missing source(with an average production rate of 0.66±0.26,0.97±0.47 and 1.45±0.55 ppbV/hr for CPs,MPPs and SPPs,respectively),which strongly correlated with photo-enhanced reactions(NO_(2)heterogeneous reaction and particulate nitrate photolysis).Average OH formation derived from HONO photolysis reached up to(0.92±0.71),(1.75±1.26)and(1.82±1.47)ppbV/hr in CPs,MPPs and SPPs respectively,much higher than that from O3 photolysis(i.e.,(0.004±0.004),(0.006±0.007)and(0.0035±0.0034)ppbV/hr).Such high OH production rates could markedly regulate the atmospheric oxidation capacity and hence promote the formation of secondary aerosols and pollutants. | Shaobin Zhang Guo Li Nan Ma Yao He Shaowen Zhu Xihao Pan Wenlin Dong Yanyan Zhang Qingwei Luo Jeannine Ditas Uwe Kuhn Yuxuan Zhang Bin Yuan Zelong Wang Peng Cheng Juan Hong Jiangchuan Tao Wanyun Xu Ye Kuang Qiaoqiao Wang Yele Sun Guangsheng Zhou Yafang Cheng Hang Su | 2023 | Journal of Environmental Sciences2023，，10： | 0 |
| 18 | Effect of temperature and stress on high temperature creep behavior of Ni_(3)Al-based single crystal superalloy显示文摘The creep behavior and dislocations mechanism of the Ni_(3)Al-based single crystal alloy IC6SX with[001]orientation were investigated under the testing conditions of 1100℃/137 MPa,1100℃/120 MPa and 1070℃/137 MPa.It was observed that the temperature and stress had a significant effect on the high temperature creep life of the single crystal alloy.As the temperature was reduced from 1100℃ to 1070℃,the creep life increased from 65.07 h to 313.8 h.As the stress was reduced to 120 MPa,the creep life increased to 243.3 h.Under the high temperature and low stress condition the dislocations entered theγ0 phase by climbing caused by the atomic diffusion,instead of slipping. | Cheng Chang Liwu Jiang Meiling Wu Shusuo Li Yafang Han | 2022 | Progress in Natural Science:Materials International2022，32，2： | 0 |
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