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A comprehensive classification method for VOC emission sources to tackle air pollution based on VOC species reactivity and emission amounts

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Journal of Environmental Sciences 2018年第5期30卷 78-88页

作者： Guohao Li Wei Wei Xia Shao lei nie Hailin Wang Xiao Yan Rui Zhang Municipal Research Institute of Environmental Protection Beijing 100037China Key Laboratory of Beijing on Regional Air Pollution Control Beijing University of TechnologyBeijing 100124China Key Laboratory of Beijing on VOC Pollution Control Technology and Application of Urban Atmosphere Beijing 100037China

In China, volatile organic compound（VOC） control directives have been continuously released and implemented for important sources and regions to tackle air pollution. The corresponding control requirements were based on VOC emission amounts（EA）, but never considered the significant differentiation of VOC species in terms of atmospheric chemical reactivity. This will adversely influence the effect of VOC reduction on air quality improvement. Therefore,this study attempted to develop a comprehensive classification method for typical VOC sources in the Beijing–Tianjin–Hebei region（BTH）, by combining the VOC emission amounts with the chemical reactivities of VOC species. Firstly, we obtained the VOC chemical profiles by measuring 5 key sources in the BTH region and referencing another 10 key sources, and estimated the ozone formation potential（OFP） per ton VOC emission for these sources by using the maximum incremental reactivity（MIR） index as the characteristic of source reactivity（SR）. Then, we applied the data normalization method to respectively convert EA and SR to normalized EA（NEA） and normalized SR（NSR） for various sources in the BTH ***, the control index（CI） was calculated, and these sources were further classified into four grades based on the normalized CI（NCI）. The study results showed that in the BTH region,furniture coating, automobile coating, and road vehicles are characterized by high NCI and need to be given more attention; however, the petro-chemical industry, which was designated as an important control source by air quality managers, has a lower NCI.

关键词： VOC Source chemical profile Source classification Beijing-Tianjin-Hebei (BTH) region

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Rapid monitoring the water extraction process of Radix Paeoniae Alba using near infrared spectroscopy

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Journal of Innovative Optical Health Sciences 2017年第3期10卷 69-76页

作者： Tian Hu Tongtong Li lei nie Lixuan Zang Hengchang Zang Yingzi Zeng School of Pharmaceutical Sciences Shandong University Wenhuaxi Road 44Jinan250012P.R.China Shandong Wohua Pharmaceutical Technology Co. Ltd Weifang261205P.R.China

Near infrared(NIR)spectroscopy has been developed into one of the most important process analytical techniques(PAT)in a wide field of *** feasibility of NIR spectroscopy with partial least square regression(PLSR)to monitor the concentration of paeoniflorin,albi-florin,gallic acid,and benzoyl paeoniforin during the water extraction process of Radix Paeoniae Alba was demonstrated and verified in this *** spectra were collected in transmission mode and pretreated with smoothing and/or derivative,and then quantitative models were built up using *** partial least squares(iPLS)method was used for the selection of spectral *** coeficients(R2aI and R2red),root mean squares error of prediction(RMSEP),root mean squares error of calibration(RMSEC),and residual predictive deviation(RPD)were applied to verify the performance of the models,and the corresponding values were 0.9873 and 0.9855,0.0487 mg/mL,0.0545mg/mL and 8.4 for paeoniforin;0.9879,0.9888,0.0303 mg/mL,0.0321 mg/mL and 9.1 for albiflorin;0.9696,0.9644,0.0140 mg/mL,0.0145 mg/mL and 5.1 for gallic acid;0.9794,0.9781,0.00169 mg/mL,0.00171 mg/mL and 6.9 for benzoyl paeoniflorin,*** results turned out that this approach was very efficient and environmentally friendly for the quantitative monitoring of the water extraction process of Radix Paeoniae Alba.

关键词： Near infrared spectroscopy partial least squares regression high performance liquid chromatography Radix Paeoniae Alba

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Asymmetric Synthesis of All Four Isomers of an Unusual Heterocycle-Containing Amino Acid ： 2-Amino-3-furan-2-yl-pentanoic Acid

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Chinese Journal of Chemistry 2012年第2期30卷 460-465页

作者： nie,lei Yang,Rui Zhang,Conghai Yin,Haichuan Yan,Shengjiao Lin,Jun Key Laboratory of Medicinal Chemistry for Natural Resource School of Chemical Science and TechnologyYunnan UniversityKunmingYunnan 650091China The Education Department of Yunnan Province KunmingYunnan 650091China

All four isomers of a novel fl-branched unusual amino acid were designed and synthesized with high stereoselectivity （〉 90% de） and in 33%--44% overall yields by the use of 4（R/S）-5,5-dimethyl-4-phenyl-oxazolidin-2-one as the chiral auxiliary via asymmetric 1,4-Michael addition, direct or indirect azidation, hydrolysis and hydrogenation reactions.

关键词： asymmetric synthesis unusual amino acid oxazolidinone chiral auxiliary 2-amino-3-furan-2-yl- pentanoic acid

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Spatial distribution of health risks for residents located close to solvent-consuming industrial VOC emission sources

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Journal of Environmental Sciences 2021年第9期33卷 38-48页

作者： Di Wang Xuan Li Xinmin Zhang Wenjuan Zhao Weiqi Zhang Shuaifeng Wu Xia Shao lei nie State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Beijing Key Laboratory of Urban Atmospheric Volatile Organic Compounds Pollution Control and Application Beijing Municipal Research Institute of Environment ProtectionBeijing 100037China China Institute of Water Resources and Hydropower Research Beijing 100038China

Emissions derived from the consumption of organic solvents have been proven to be the primary industrial source of volatile organic compounds(VOCs).In conjunction with epidemiologic studies, water-based paints(WBPs) and solvent-based paints(SBPs) were selected as representatives of newly developed solvents and traditional solvents, respectively,to simulate the effects of consuming solvents emitted during industrial *** non-carcinogenic and carcinogenic risks to residents near emission sources were studied in *** results showed that the spatial distribution of health risks varied with meteorological conditions and type of emission source, and the prevailing wind direction strongly affected the distribution range and shape of the influenced *** areas of influence maximized on heavy-polluting days for both WBP and SBP emission sources with the total span reaching 804 m and 16 km, respectively;meanwhile, the areas of influence for carcinogenic risk resulting from WBP emission sources were 1.2 and 2.3 times greater than those measured on fine and rainy days, respectively, and 1.8 and 2.9 times greater for SBP emission *** with WBPs, the total spans of negatively influenced regions resulting from SBP emission sources were 10.4, 12.5 and 19.9 times greater on fine, rainy and heavypolluting days, ***, carcinogenic risk was the dominant health threat for populations residing close to solvent-consuming industrial emission *** findings suggest that newly developed solvents are capable of significantly reducing consequent health threats, nevertheless, they could still pose occasional threats to nearby residents under specific meteorological conditions.

关键词： Secondary receptor Spatial distribution Solvent-consuming emission source Potential health risk Acquirable risk-free region

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Spectra selection methods:A novel optimization way for treating dynamic spectra and in-line near infrared modeling

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Journal of Innovative Optical Health Sciences 2020年第4期3卷 28-38页

作者： Haiyan Wang Ronghua Liu lei nie Dongbo Xu Wenping Yin Lian Li Hengchang Zang School of Pharmaceutical Sciences Shandong University Wenhuaxi Road 44 Jinan 250012P.R.China National Glycoengineering Research Center Shandong University Wenhuaxi Road 44 Jinan 250012 P.R.China Shandong SMA Pharmatech Co. Ltd 165Huabei Rd.High&New Technology Zone Zibo Shandong 0533P.R.China

Near infrared(NIR)spectroscopy is now widely used influidized bed ***,there are still some demerits that should be overcome in *** spectra selection during modeling process is now a hard nut to *** this study,a novel NIR sensor and a cosine distance method were introduced to solve this problem in order to make thefluidized process into"visualization".A NIR sensor wasfixed on the side of the expansion chamber to acquire the NIR *** valid spectra were selected based on a cosine distance method to reduce the influence of dynamic ***,spectral pretreatment and wavelength selection methods were investigated to establish partial least squares(PLS)models to monitor the mois-ture *** results showed that the root mean square error of prediction(RMSEP)was 0.124%for moisture content model,which was much lower than that without valid spectra selection *** results demonstrated that with the help of valid spectra selection treatment,NIR sensor could be used for real-time determination of critical quality attributes(CQAs)more *** makes the manufacturing easier to understand than the process parameter control.

关键词： Near infrared spectroscopy fluidized bed granulation critical quality attributes real-time monitoring spectra selection

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Multi-dimension apportionment of clean air “parade blue”phenomenon in Beijing

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Journal of Environmental Sciences 2018年第3期30卷 29-42页

作者： Yifeng Xue Yong Wang Xuefeng Li Hezhong Tian lei nie Xiaoqing Wu Junrui Zhou Zhen Zhou State Key Joint Laboratory of Environmental Simulation & Pollution Control School of Environment Beijing Normal University Beijing 100875 China National Engineering Research Center of Urban Environmental Pollution Control Beijing Municipal Research Institute of Environmental Protection Beijing 100037 China Center of Atmospheric Environmental Studies Beijing Normal University Beijing 100875 China Wuhan Environmental Protection Sciences Research Institute Wuhan 430015 China

The mass concentration and major chemical components of fine particulate matter were measured before,during and after Beijing＇s massive parade commemorating 70th anniversary of the Chinese Victory in World War II on September 3,*** emission inventory,positive matrix factorization（PMF）,observations from space and backward air mass trajectories were jointly applied to identify the major pollution sources and their temporal and spatial *** contributions of emissions variations and the meteorological conditions related to the＂parade blue＂phenomenon in Beijing and its surrounding areas were investigated in *** main cause of the decreased PM（2.5）mass concentration was attributed to the absolute reduction in emissions of primary air *** chemical composition of PM（2.5）varied significantly before,during and after the *** dust particles were well controlled,the secondary formation of PM（2.5）was reduced along with the controlled gaseous precursors＇emissions from vehicles and industrial sources during the temporary intensified control *** the parade period,the SO2and NO2column concentrations in Beijing and the surrounding areas decreased sharply,indicating that the coordinated reduction in primary emissions from the surrounding areas of Beijing played an important role in lowering the ambient concentration of SO2and NO2and accordingly lowered PM（2.5）and improved the regional air quality.A comparison of the temperature,humidity,and wind speed and direction during the same periods in 2014 and 2015 showed that the meteorological conditions positively influenced the achievement of＂parade blue＂.

关键词： PM2.5 Parade Blue in Beijing Emission reduction Air quality Source apportionment Meteorological conditions

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Inferring Functional Connectivity in fMRI Using Minimum Partial Correlation

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International Journal of Automation and computing 2017年第4期14卷 371-385页

作者： lei nie Xian Yang Paul M. Matthews Zhi-Wei Xu Yi-Ke Guo Department of Computing Imperial College London London SW7 2AZ UK Department of Medicine Imperial College London London SW7 2AZ UK Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China School of Computer Engineering and Science Shanghai University Shanghai 200444 China

Functional connectivity has emerged as a promising approach to study the functional organisation of the brain and to define features for prediction of brain state. The most widely used method for inferring functional connectivity is Pearson＇s correlation, but it cannot differentiate direct and indirect effects. This disadvantage is often avoided by computing the partial correlation between two regions controlling all other regions, but this method suffers from Berkson＇s paradox. Some advanced methods, such as regularised inverse covariance, have been applied. However, these methods usually depend on some parameters. Here we propose use of minimum partial correlation as a parameter-free measure for the skeleton of functional connectivity in functional magnetic resonance imaging （flVIRI）. The minimum partial correlation between two regions is the minimum of absolute values of partial correlations by controlling all possible subsets of other regions. Theoretically, there is a direct effect between two regions if and only if their minimum partial correlation is non-zero under faithfulness and Gaussian assumptions. The elastic PC-algorithm is designed to efficiently approximate minimum partial correlation within a computational time budget. The simulation study shows that the proposed method outperforms others in most cases and its application is illustrated using a resting-state fMRI dataset from the human connectome project.

关键词： Functional connectivity functional magnetic resonance imaging (fMRI) network modelling partial correlation PC-algorithm resting-state networks.

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A useful quantitative model for determination of enantiomeric composition of racemate praziquantel by ultraviolet spectroscopy combined with partial least squares and its application to praziquantel tablets

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Journal of Innovative Optical Health Sciences 2018年第3期11卷 46-53页

作者： Man Zhao Ran Meng Yifang Lu Lingyun Hu Na Sun lei nie Haina Wang School of Pharmaceutical Sciences Shandong University Jinan 250012P.R.China Shandong Cancer Hospital A±liated to Shandong University Jinan P.R.China

A simple and novel method has been proposed to determine the enantiomeric composition ofracemate praziquantel(PzQ)by using the analysis of ultraviolet(UV)spectroscopy combinedwith partial least squares(PLS),This method does not rely on the use of expensive carbohydratessuch as cyclodextrins,but on the use of inexpensive sucrose,which is equally effective as *** has two *** measuring the slight diference in the UV spectralabsorption of PzQ due to different interactions between its two enantiomers and sucrose,theenantiomeric composition was determined by a quantitative model based on PLS *** showed that the correlation coeficients of calibration set and validation set were 0.9971and 0.9972,*** root mean square error of calibration(RMSEC)and the root meansquare error of prediction(RMSEP)were 0.0167 and 0.0129,respectively,Then,the independentdata of PZQ tablets were also used to test how well the quantitative model of PLS predicted theenantiomeric composition,The ratio of S-PZQ in tablet was 0.492,determined by high-perfor-mance liquid chromatography as the reference value,Six solutions of the tablet samples were prepared,and the ratios of S-PZQ in tablet samples in the validation set were predicted by the PLS model.,Theirrelative erors with the reference value were not more than 4%.Therefore,the established model couldbe accurate and employed to predict the enantiomeric compositions of PzQ tablets.

关键词： Enantiomeric compositions praziquantel partia last squares utraviolet spectrscopy sucrose

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Coupling microchip electrophoresis with MALDI-TOF-MS based on a freezing technique

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Chinese Chemical Letters 2013年第6期24卷 491-493页

作者： lei nie Guo-Bin Xu Xiao-Yan Wang Yun Liu Peng-Yuan Yang Department of Chemistry Fudan University Institutes of Biomedical Sciences of Shanghai Medical College Fudan University

A freezing technique protocol was proposed for coupling microchip electrophoresis with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（MALD1-TOF-MS）.The microfluidic flow was frozen immediately after electrophoresis on microfluidic chip and the separated analyte molecules were kept in their zone pattern in the ***,the frozen-chip was lyophilized and sent into TOF-MS instrument as a MALDI target,and the analyte molecules in the microfluidic channels were subjected to analysis by mass *** approach could eliminate sample cross-contamination, providing a new interface for microchip electrophoresis and MALDI-MS.

关键词： Microchip electrophoresis MALDI-TOF-MS Peptide analysis Freezing technique

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Linear Liquid Responses of Morpho Butterfly Structural Color： Experiment and Modeling

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Wuhan University Journal of Natural Sciences 2016年第6期21卷 473-481页

作者： WU Wenjun XIE Hengfeng LIAO Guanglan SHI Tielin nie lei Key Laboratory of Modern Manufacture Quality Engineering Hubei University of Technology Wuhan 430068Hubei China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430070 Hubei China

This paper investigates the selective liquid response for Morpho didius butterfly wing scales and propose an optical model to explain the effect of different components on the liquid response. It is found out that the reason of the selective response is that the liquid media forms nanometre-thick films between ridge-lamellae nanostructures and changes the constructive interference wavelength. There is linear relation between the structural color of ridge-lamellae structure and index of liquid background media. The reason of vapor＇s responses is that the nanometre-thick liquid fi lms on ridge-lamellae nanostructures change the constructive interference wavelength. These liquid films are formed due to vapor adsorption. Therefore,the selective linear liquid response can be applied to design nano-engineered photonic liquid and vapor sensors.

关键词： nano-engineered photonic sensors ridge-lamellae nanostructures structural color linear liquid response

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