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19篇 您的检索式:作者名="LI PinHua"
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1Long-term observations of tropospheric NO_2, SO_2 and HCHO by MAX-DOAS in Yangtze River Delta area, China显示文摘Yangtze River Delta(YRD) area is one of the important economic zones in China. However,this area faces increasing environmental problems. In this study, we use ground-based multi-axis differential optical absorption spectroscopy(MAX-DOAS) network in Eastern China to retrieve variations of NO_2, SO_2, and formaldehyde(HCHO) in the YRD area. Three cities of YRD(Hefei, Nanjing, and Shanghai) were selected for long-term observations. This paper presents technical performance and characteristics of instruments, their distribution in YRD, and results of vertical column densities(VCDs) and profiles of NO_2, SO_2, and HCHO.Average diurnal variations of tropospheric NO_2 and SO_2 in different seasons over the three stations yielded minimum values at noon or in the early afternoon, whereas tropospheric HCHO reached the maximum during midday hours. Slight reduction of the pollutants in weekends occurred in all the three sites. In general trace gas concentrations gradually reduced from Shanghai to Hefei. Tropospheric VCDs of NO_2, SO_2, and HCHO were compared with those from Ozone Monitoring Instrument(OMI) satellite observations, resulting in R^2 of 0.606, 0.5432, and 0.5566, respectively. According to analysis of regional transports of pollutants, pollution process happened in YRD under the north wind with the pollution dissipating in the southeast wind. The feature is significant in exploring transport of tropospheric trace gas pollution in YRD, and provides basis for satellite and model validation.Xin Tian Pinhua Xie Jin Xu Ang Li Yang Wang Min Qin Zhaokun Hu 2018Journal of Environmental Sciences2018,30,9:7
2Variation of temporal and spatial patterns of NO_2 in Beijing using OMI and mobile DOAS显示文摘Control policies such as 'odd-and-even license plate rule' were implemented by the Chinese government to restrict traffic and suspend factory production in Beijing and neighboring cities during the Asia-Pacific Economic Cooperation summit. We use ozone monitoring instrument(OMI), mobile differential optical absorption spectroscopy(DOAS), and multi-axis differential optical absorption spectroscopy(MAX-DOAS) to measure the variation of the spatial and temporal patterns of NO2 column densities from October 24, 2014 to November 22, 2014. It is found that the NO2 column densities during the episode of control policies are significantly lower than those during other periods, and the emission flux of NO2 calculated by mobile DOAS is also lower than the results from other periods. Some daily low NO2 column densities occur with the northwest wind direction. We then compare the relationship between OMI and mobile DOAS NO2 column density observations, and the results of mobile DOAS are approximately 2.7 times larger than the OMI values. The largest discrepancy occurs in the northern part of Beijing city. In other parts, the two instruments have a better correlation coefficient(R2) of 0.61. The low NO2 column densities that occur during the episode of control policies are affected by the control policies as well as meteorological conditions.Ang Li Jie Zhang Pinhua Xie Zhaokun Hu Jin Xu Fusheng Mou Fengcheng Wu Jianguo Liu Wenqing Liu 2015Science China Chemistry2015,58,9:5
3Immobilized nickel(Ⅱ) on organic-inorganic hybrid materials: The effective and reusable catalysts for Biginelli reaction显示文摘The immobilized nickel(II) on the organic-inorganic hybrid material was prepared and used as an effective catalyst for the Biginelli reaction.In the presence of the immobilized nickel catalyst,aromatic aldehydes reacted with ethyl acetoacetate and urea (or thiourea) smoothly to generate the corresponding Biginelli products in good to excellent yields without using any additive.The work-up procedure is very simple and practical.Furthermore,the silica-supported nickel(II) could be recovered and recycled for six consecutive trials without significant loss of its catalytic activity.ZHANG LiYuan WANG ChuanHu ZHOU Li LI PinHua ZHANG XiuLi WANG Lei 2011Science China Chemistry2011,54,1:3
4Reduction of nitroarones to aromatic amines with nanosized activated metallic iron powder in water显示文摘 Pinhua Li Zangtao Wu 2003Synthesis2003,13,:1
5A hydroxyl radical detection system using gas expansion and fast gating laser-induced fluorescence techniques显示文摘An OH radical measurement instrument based on Fluorescence Assay by Gas Expansion(FAGE)has been developed in our laboratory.Ambient air is introduced into a low-pressure fluorescence cell through a pinhole aperture and irradiated by a dye laser at a high repetition rate of 8.5 k Hz.The OH radical is both excited and detected at 308 nm using A-X(0,0)band.To satisfy the high efficiency needs of fluorescence collection and detection,a 4-lens optical system and a self-designed gated photomultiplier(PMT)is used,and gating is actualized by switching the voltage applied on the PMT dynodes.A micro channel photomultiplier(MCP)is also prepared for fluorescence detection.Then the weak signal is accumulated by a photon counter in a specific timing.The OH radical excitation spectrum range in the wavelength of 307.82–308.2 nm is detected and the excited line for OH detection is determined to be Q_1(2)line.The calibration of the FAGE system is researched by using simultaneous photolysis of H_2O and O_2.The minimum detection limit of the instrument using gated PMT is determined to be 9.4×10~5molecules/cm^3,and the sensitivity is 9.5×10^(-7)cps/(OH·cm^(-3)),with a signal-to-noise ratio of 2 and an integration time of 60 sec,while OH detection limit and the detection sensitivity using MCP is calculated to be 1.6×10~5molecules/cm^3and 2.3×10^(-6)cps/(OH·cm^(-3)).The laboratory OH radical measurement is carried out and results show that the proposed system can be used for atmospheric OH radical measurement.Hao Chen Renzhi Hu Pinhua Xie Xingbiao Xing Liuyi Ling Zhiyan Li Fengyang Wang Yihui Wang Jianguo Liu Wenqing Liu 2018Journal of Environmental Sciences2018,30,3:1
6Community structure and assembly of denitrifying bacteria in epiphytic biofilms in a freshwater lake ecosystem显示文摘Denitrifying bacteria are a crucial component of aquatic ecosystem in nitrogen cycle.However,the denitrifying bacterial community dynamics and structure in epiphytic biofilms remain unexplored.The abundance of denitrification gene(nir)and structure of nirS-denitrifying bacterial community in the epiphytic biofilms collected in July and November of 2018 from a typical plateau lake(Caohai Wetland,Guizhou,China)were studied by Real-time Quantitative Polymerase Chain Reaction(qPCR)and highthroughput sequencing.Results show that the gene abundance of nirK was higher than that of nirS(P<0.05),and it was significantly different during the growth period(July)than the decline period(November).The denitrifying bacterial species was similar in the two months and shared 76.18%of OTUs.Proteobacteria(56.55%±22.15%)was the dominant phylum in all the samples.Epiphytic biofilms between growth period and decline period displayed significantly different microbial community structures due to differences in species abundance.Water temperature was the crucial factor that affected the denitrifying microbial community structure in our study.Environmental factors explain only partially the dynamic characteristics of denitrifying microbial communities,implying that the stochastic processes affected the construction of denitrifying microbial communities.As the null model analysis results show,dispersal limitation(stochastic)and undominated processes significantly influenced the assembly of denitrifying microbial communities.This study broadened our understanding of the denitrifying bacterial community structure and its function on epiphytic biofilms in freshwater ecosystems with new information provided.Guoqing LI Dingbo YAN Pinhua XIA Haipeng CAO Tao LIN Yin YI 2022Journal of Oceanology and Limnology2022,40,3:1
7Application of smog chambers in atmospheric process studies显示文摘Smog chamber experimental systems,which have been widely used in laboratory simulation for studying atmospheric processes,are comprehensively reviewed in this paper.The components,development history,main research topics and main achievements of smog chambers are introduced.Typical smog chambers in the world,including their volumes,wall materials,light sources and features,are summarized and compared.Key factors of smog chambers and their influences on the simulation of the atmospheric environment are discussed,including wall loss,wall emission and background pollutants.The features of next-generation smog chambers and their application prospect in future studies of the atmospheric environment are also outlined in this paper.Biwu Chu Tianzeng Chen Yongchun Liu Qingxin Ma Yujing Mu Yonghong Wang Jinzhu Ma Peng Zhang Jun Liu Chunshan Liu Huaqiao Gui Renzhi Hu Bo Hu Xinming Wang Yuesi Wang Jianguo Liu Pinhua Xie Jianmin Chen Qian Liu Jingkun Jiang Junhua Li Kebin He Wenqing Liu Guibin Jiang Jiming Hao Hong He 2022National Science Review2022,9,2:1
8Photochemical and electrochemical strategies in C-F bond activation and functionalization显示文摘The activation and functionalization of C-F bonds under mild conditions can serve as an important tool for organic syntheses including the modification of pharmaceuticals and agrochemicals and the synthesis of value-added chemicals.However,owing to their high energy and low activity,C-F bonds are difficult to activate.Zhanghong Wang Yu Sun Liu-Yu Shen Wen-Chao Yang Fei Meng Pinhua Li 2022Organic Chemistry Frontiers2022,9,3:1
9Key emergency response technologies for abrupt air pollution accidents in China显示文摘Abrupt air pollution accidents can endanger people’s health and destroy the local ecological environment.The appropriate emergency response can minimize the harmful effects of accidents and protect people’s lives and property.This paper provides an overview of the key emergency response technologies for abrupt air pollution accidents around the globe with emphasis on the major achievements that China has obtained in recent years.With decades of effort,China has made significant progress in emergency monitoring technologies and equipment,source estimation technologies,pollutant dispersion simulation technologies and others.Many effective domestic emergency monitoring instruments(e.g.,portable DOAS/FT-IR systems,portable FID/PID systems,portable GC-MS systems,scanning imaging remote sensing systems,and emergency monitoring vehicles)had been developed which can meet the demands for routine emergency response activities.A monitoring layout technique combining air dispersion simulation,fuzzy comprehensive evaluation,and a post-optimality analysis was proposed to identify the optimal monitoring layout scheme under the constraints of limited monitoring resources.Multiple source estimation technologies,including the forward method and the inversion method,have been established and evaluated under various scenarios.Multi-scale dynamic pollution dispersion simulation systems with high temporal and spatial resolution were further developed.A comprehensive emergency response platform integrating database support,source estimation,monitoring schemes,fast monitoring of pollutants,pollution predictions and risk assessment was developed based on the technical idea of'source identification-model simulation-environmental monitoring'dynamic interactive feedback.It is expected that the emergency response capability for abrupt air pollution accidents will gradually improve in China.Jun Duan Shushuai Mao Pinhua Xie Jianlei Lang Ang Li Jingjing Tong Min Qin Jin Xu Zeya Shen 2023Journal of Environmental Sciences2023,,1:1
10Direct Retrieval of NO_(2)Vertical Columns from UV-Vis(390-495nm)Spectral Radiances Using a Neural Network显示文摘Satellite retrievals of columnar nitrogen dioxide(NO_(2))are essential for the characterization of nitrogen oxides(NO_(x))processes and impacts.The requirements of modeled a priori profiles present an outstanding bottleneck in operational satellite NO_(2)retrievals.In this work,we instead use neural network(NN)models trained from over 360,000 radiative transfer(RT)simulations to translate satellite radiances across 390-495nm to total NO_(2)vertical column(NO_(2)C).Despite the wide variability of the many input parameters in the RT simulations,only a small number of key variables were found essential to the accurate prediction of NO_(2)C,including observing angles,surface reflectivity and altitude,and several key principal component scores of the radiances.In addition to the NO_(2)C,the NN training and cross-validation experiments show that the wider retrieval window allows some information about the vertical distribution to be retrieved(e.g.,extending the rightmost wavelength from 465 to 495 nm decreases the root-mean-square-error by 0.75%)under high-NO_(2)C conditions.Applying to four months of TROPOMI data,the trained NN model shows strong ability to reproduce the NO_(2)C observed by the ground-based Pandonia Global Network.The coefficient of determination(R2,0.75)and normalized mean bias(NMB,-33%)are competitive with the level 2 operational TROPOMI product(R^(2)=0:77,NMB=−29%)over clear(geometric cloud fraction<0:2)and polluted(NO_(2)C≥7:5×10^(15)molecules/cm2)regions.The NN retrieval approach is~12 times faster than predictions using high spatial resolution(~3 km)a priori profiles from chemical transport modeling,which is especially attractive to the handling of large volume satellite data.Chi Li Xiaoguang Xu Xiong Liu Jun Wang Kang Sun Jos van Geffen Qindan Zhu Jianzhong Ma Junli Jin Kai Qin Qin He Pinhua Xie Bo Ren Ronald C.Cohen 2022Journal of Remote Sensing2022,,1:0
11Atmospheric environment monitoring technology and equipment in China:A review and outlook显示文摘Accurate monitoring of the atmospheric environment and its evolution are important for understanding the sources,chemical mechanisms,and transport processes of air pollution and carbon emissions in China,and for regulatory and control purposes.This study gives an overview of atmospheric environment monitoring technology and equipment in China and summarizes the major achievements obtained in recent years.China has made great progress in the development of atmospheric environment monitoring technology and equipment with decades of effort.The manufacturing level of atmospheric environment monitoring equipment and the quality of products have steadily improved,and a technical&production system that can meet the requirements of routine monitoring activities has been initiated.It is expected that domestic atmospheric environment monitoring technology and equipment will be able to meet future demands for routine monitoring activities in China and provide scientific assistance for addressing air pollution problems.Youwen Sun Ting Yang Huaqiao Gui Xin Li Weigang Wang Jun Duan Shushuai Mao Hao Yin Bin Zhou Jianlei Lang Haijin Zhou Cheng Liu Pinhua Xie 2023Journal of Environmental Sciences2023,,1:0
12Visible-light-induced chemoselective reactions of quinoxalin-2(1H)-ones with alkylboronic acids under air/N_(2) atmosphere显示文摘A visible-light-induced chemoselective reactions of quinoxalin-2(1 H)-ones with alkylboronic acids in the presence of air(O_(2)) and N_(2)atmosphere was developed under transition-metal free conditions, providing 3-alkylquinoxalin-2(1H)-ones and 3,4-dihydroquinoxalin-2(1H)-ones, respectively. The overall strategy accommodates a broad scope of substituted quinoxalin-2(1H)-ones and alkylboronic acids with good to excellent product yields.Lingling Yao Defeng Zhu Lei Wang Jie Liu Yicheng Zhang Pinhua Li 2021Chinese Chemical Letters2021,32,12:0
13Genome-wide analysis identify novel germline genetic variations in ADCY1 influencing platinum-based chemotherapy response in nonsmall cell lung cancer显示文摘To explore the pharmacogenomic markers that affect the platinum-based chemotherapy response in non-small-cell lung carcinoma(NSCLC),we performed a two-cohort of genome-wide association studies(GWAS),including 34 for WES-based and 433 for microarray-based analyses,as well as two independent validation cohorts.After integrating the results of two studies,the genetic variations related to the platinum-based chemotherapy response were further determined by fine-mapping in 838 samples,and their potential functional impact were investigated by eQTL analysis and in vitro cell experiments.We found that a total of 68 variations were significant at P<1×10^(-3)in cohort 1 discovery stage,of which 3 SNPs were verified in 262 independent samples.A total of541 SNPs were significant at P<1×10^(-4)in cohort 2 discovery stage,of which 8 SNPs were verified in 347 independent samples.Comparing the validated SNPs in two GWAS,ADCY1 gene was verified in both independent studies.The results of fine-mapping showed that the G allele carriers of ADCY1rs2280496 and C allele carriers of rs189178649 were more likely to be resistant to platinum-based chemotherapy.In conclusion,our study found that rs2280496 and rs189178649 in ADCY1 gene were associated the sensitivity of platinum-based chemotherapy in NSCLC patients.Chenxue Mao Juan Chen Ting Zou Yuankang Zhou Junyan Liu Xi Li Xiangping Li Min Li Pinhua Pan Wei Zhuo Yang Gao Shuo Hu Desheng Xiao Lin Wu Zhan Wang Heng Xu Wen Yang Yingjie Xu Haihua Xiao Kazuhiko Hanada Wei Zhang Honghao Zhou Jiye Yin Zhaoqian Liu 2022Acta Pharmaceutica Sinica B2022,12,3:0
14Visible-light-induced photoredox-catalyzed synthesis of benzimidazo[2,1-a]iso-quinoline-6(5H)-ones显示文摘A simple and efficient visible-light-induced photo redox-catalyzed diarylation of N-methacryloyl-2-arylbenzoimidazoles with aryl diazonium salts was developed.The reaction provides a conve nient access to a variety of benzimidazoisoquinolinones through the construction of two C-C bonds in one step under mild reaction conditions.Bin Wang Long Zou Lei Wang Manman Sun Pinhua Li 2021Chinese Chemical Letters2021,32,3:0
15Visible-light-induced novel cyclization of 2-(2-(arylethynyl)benzylidene)-malononitrile derivatives with 2,6-di(tert-butyl)-4-methylphenol to bridged spirocyclic compounds显示文摘A green and highly efficient strategy for the preparation of bridged spirocyclic compounds via visible-light-induced cyclization of 2-(2-(arylethynyl)benzylidene)malononitrile derivatives with 2,6-di(tert-butyl)-4-methylphenol(BHT)at room temperature was developed.The photoinduced radical reactions generated the corresponding products in good yields under simple and mild reaction conditions.Xiaofei Xie Lei Wang Quan Zhou Yongmin Ma Zhi-Ming Wang Pinhua Li 2022Chinese Chemical Letters2022,33,12:0
16Study of aerosol characteristics and sources using MAX-DOAS measurement during haze at an urban site in the Fenwei Plain显示文摘Atmospheric aerosols have effects on atmospheric radiation assessments,global climate change,local air quality and visibility.In particular,aerosols are more likely transformed and accumulated in winter.In this paper,we used the Multi-Axis Differential Optical Absorption Spectroscopy(MAX-DOAS)instrument to study the characteristics of aerosol type and contributions of PM_(2.5) chemical components to aerosol extinction(AE),vertical distribution of aerosols,and source.From December 30,2018 to January 27,2019,we conducted MAX-DOAS observations on Sanmenxia.The proportion of PM_(2.5) to PM10 was 69.48%-95.39%,indicating that the aerosol particles were mainly fine particles.By analyzing the ion data and modifying Interagency Monitoring of Protected Visual Environments(IMPROVE)method,we found that nitrate was the largest contributor to AE,accounting for 31.51%,28.98%,and 27.95%of AE on heavily polluted,polluted,and clean days,respectively.NH4+,OC,and SO42-were also major contributors to AE.The near-surface aerosol extinction retrieved from MAX-DOAS measurement the PM_(2.5) and PM10 concentrations measured by an Unmanned Aerial Vehicle(UAV)have the same trend in vertical distribution.AE increased about 3 times from surface to 500 m.With the backward trajectory of the air mass during the haze,we also found that the continuous heavy pollution was mainly caused by transport of polluted air from the northeast,then followed by local industrial emissions and other sources of emissions under continuous and steady weather conditions.Xiaomei Li Pinhua Xie Ang Li Jin Xu Hongmei Ren Bo Ren Yanyu Li Jie Li 2021Journal of Environmental Sciences2021,33,9:0
17A practical synthesis of α-bromo/iodo/chloroketones from olefins under visible-light irradiation conditions显示文摘A practical synthesis of α-bromo/iodo/chloroketones from olefins under visible-light irradiation conditions has been developed.In the presence of PhI(OAc)_(2) as promoter and under ambient conditions,the reactions of styrenes and triiodomethane undergo the transformation smoothly to deliver the corresponding a-iodoketones without additional photocatalyst in good yields under sunlight irradiation.Mea nwhile,the reactions of styrenes with tribromomethane and trichloromethane generate the desiredα-bromoketones and a-chloroketones in high yields by using Ru(bpy)_(3)Cl_(2) as a photocatalyst under blue LED(450-455 nm) irradiation.Zhihui Wang Lei Wang Zhiming Wang Pinhua Li Yicheng Zhang 2021Chinese Chemical Letters2021,32,1:0
18Lake regime shift from submerged macrophyte to phytoplankton affected phosphorus speciation in sediment and eutrophic state in Caohai Lake,Guizhou,China显示文摘To understand the effect of regime shift in Caohai Lake in Yunnan-Guizhou Plateau,SW China from submerged macrophyte dominance to phytoplankton dominance on the specification and distribution of phosphorus and on ecological and environmental states,changes in phosphorus specification in the sediments and water were studied.The form,composition,and distribution of phosphorus in sediment were sampled in July 2020(before regime shift)and July 2021(after regime shift)were analyzed.Results reveal that phosphorus content in sediment was lower than that those of Erhai Lake and Dianchi Lake,Yunnan,SW China,on the same plateau,and was lower than those of Taihu Lake,Chaohu Lake,and Poyang Lake in the middle-lower Changjiang(Yangtze)River Plain.Organic phosphorus(Or-P)was the main form(up to 60%),followed by inactive phosphorus(Ina-P),and the active phosphorus(Act-P),the least,which is opposite to those of Taihu Lake and Poyang Lake in the middle-lower Changjiang River Plain in the eastern China.Or-P content was high,indicating a high potential risk of phosphorous release.After the regime shift,the total phosphorus in sediment decreased from 0.87±0.13 to 0.70±0.13 g/kg.The proportion of Or-P and Act-P decreased from 68.23% to 65.32% and from 5.35% to 4.69%,respectively.In contrast,the proportion of Ina-P increased from 26.42% to 29.99%.The Moran’s I index revealed that the heterogeneity of the spatial distributions of the total phosphorus(S-TP)and Act-P in the sediments before regime shift was significant(P<0.1).However,the heterogeneity of the spatial distributions of S-TP and the various forms of phosphorus after regime shift was not significant(P>0.05).The regime shift aggravated the eutrophication of the lake,the trophic level index(TLI)increased from 48.42 to 54.49(P<0.01),and the previously mesotrophic lake became a mildly eutrophic lake.The results of this study revealed the impact of regime shift in the lake from submerged macrophyte dominance to phytoplankton dominance on the composition and spatial distribution of phosphorus in sediments and provided a basis for the restoration of eutrophicated and aquatic ecosystem degraded lakes.Jixing DONG Yanmin GUO Pinhua XIA Yuanbin TIAN Feifei ZHENG Anyan LI Tao LIN Ruiwen LI 2023Journal of Oceanology and Limnology2023,41,6:0
19Temporal characteristics of algae-denitrifying bacteria co-occurrence patterns and denitrifier assembly in epiphytic biofilms on submerged macrophytes in Caohai Lake,SW China显示文摘Denitrifying bacteria in epiphytic biofilms play a crucial role in nitrogen cycle in aquatic habitats.However,little is known about the connection between algae and denitrifying bacteria and their assembly processes in epiphytic biofilms.Epiphytic biofilms were collected from submerged macrophytes(Patamogeton lucens and Najas marina L.)in the Caohai Lake,Guizhou,SW China,from July to November 2020 to:(1)investigate the impact of abiotic and biotic variables on denitrifying bacterial communities;(2)investigate the temporal variation of the algae-denitrifying bacteria co-occurrence networks;and(3)determine the contribution of deterministic and stochastic processes to the formation of denitrifying bacterial communities.Abiotic and biotic factors influenced the variation in the denitrifying bacterial community,as shown in the Mantel test.The co-occurrence network analysis unveiled intricate interactions among algae to denitrifying bacteria.Denitrifying bacterial community co-occurrence network complexity(larger average degrees representing stronger network complexity)increased continuously from July to September and decreased in October before increasing in November.The co-occurrence network complexity of the algae and nirS-encoding denitrifying bacteria tended to increase from July to November.The co-occurrence network complexity of the algal and denitrifying bacterial communities was modified by ammonia nitrogen(NH_(4)^(+)-N)and total phosphorus(TP),pH,and water temperature(WT),according to the ordinary least-squares(OLS)model.The modified stochasticity ratio(MST)results reveal that deterministic selection dominated the assembly of denitrifying bacterial communities.The influence of environmental variables to denitrifying bacterial communities,as well as characteristics of algal-bacterial co-occurrence networks and the assembly process of denitrifying bacterial communities,were discovered in epiphytic biofilms in this study.The findings could aid in the appropriate understanding and use of epiphytic biofilms denitrification function,as well as the enhancement of water quality.Pinhua XIA Guoqing LI Xianfei HUANG Lei SHI Xin DU Tao LIN 2023Journal of Oceanology and Limnology2023,41,6:0
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