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Pollution characteristics of 15 gas- and particle-phase phthalates in indoor and outdoor air in Hangzhou

Journal of Environmental Sciences 2019年第12期31卷 107-119页

作者： Xingzi Ouyang Meng Xia Xueyou Shen Yu zhan College of Environmental&Resource Sciences Zhejiang UniversityHangzhouZhejiang 310058China Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control HangzhouZhejiang 310058China Department of Environmental Science and Engineering Sichuan UniversityChengduSichuan 610065China

Phthalate esters(PAEs),typical pollutants widely used as plasticizers,are ubiquitous in various indoor and outdoor *** exist in both gas and particle phases,posing risks to human *** the present study,we chose four typical kinds of indoor and outdoor environments with the longest average human residence times to assess the human exposure in Hangzhou,including newly decorated residences,ordinary residences,offices and outdoor *** order to analyze the pollution levels and characteristics of 15 gasand particle-phase PAEs in indoor and outdoor environments,air and particulate samples were collected *** total PAEs concentrations in the four types of environments were 25,396,25,466.8,15,388.8 and 3616.2 ng/m^3,*** and DEP were the most abundant,and DMPP was at the lowest *** variations in the distributions of indoor/outdoor,gas/particle-phase and different molecular weights of PAEs were observed,showing that indoor environments were the main sources of PAEs *** most PAEs tended to exsit in indoor sites and gas-phase,the high-molecular-weight chemicals tended to exist in the particle-phase and were mainly found in *** were more likely adsorbed by small particles,especially for the indoor *** existed a good correlation between the particle matter concentrations and the PAEs *** addition,neither temperature nor humidity had obvious effects on the distributions of the PAEs concentrations.

关键词： Phthalate esters Indoor and outdoor air Gas and particle phase Distribution characteristics Particles

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Effect of tempering temperature on the microstructure and properties of ultrahigh-strength stainless steel

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Journal of Materials Science & Technology 2019年第7期35卷 1240-1249页

作者： Yangpeng zhang Dongping zhan Xiwei Qi Zhouhua Jiang School of Metallurgy Northeastern UniversityShenyang110819China School of Materials Science and Engineering Northeastern UniversityShenyang110819China

The microstructure, precipitation and mechanical properties of Ferrium S53 steel, a secondary hardening ultrahigh-strength stainless steel with 10% Cr developed by QuesTek Innovations LLC, upon tem pering were studied by scanning electron microscopy (SEM), transm ission electron microscopy (TEM), X-ray diffraction (XRD), and tensile and impact tests. Based on these results, the influence of the tem pering temperature on the microstructure and properties was discussed. The results show th at decom position occurred when the retained austenite was tem pered above 440 ℃ and that the hardening peak at 482 ℃ was caused by the joint strengthening of the precipitates and martensite transformation. Due to the high Cr content, the trigonal M7C3 carbide precipitated w hen the steel was tem pered at 400 ℃, and M7C3 and M2C (5 -10 nm in size) coexisted w hen it was tem pered at 482 ℃. When the steel was tem pered at 630 ℃, M2C and M23C6 carbides precipitated, and the sizes w ere greater than 50 nm and 500 nm, respectively, but no M7C3 carbide formed. When the tempering tem perature was above 540 ℃, austenitization and large-size precipitates w ere the main factors affecting the strength and toughness.

关键词： Age hardening Austenite Precipitation Tempering Strengthening mechanism M7C3

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non-UV Photoelectric Properties of the ni/n-Si/n+-SiC Isotype Heterostructure Schottky Barrier Photodiode

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Chinese Physics Letters 2013年第9期30卷 149-152页

作者： LI Lian-Bi CHEn Zhi-Ming REn zhan-Qiang GAO zhan-Jun Department of Electronic Engineering Xi’an University of TechnologyXi’an 710048 School of Science Xi’an Polytechnic UniversityXi’an 710048

The energy-band structure and non-ultraviolet photoelectric properties of a ni/n-Si/n^(+)-SiC isotype heterostruc-ture Schottky photodiode are simulated by using *** are energy offsets in the conduction and valance band of the heterojunction,which are about 0.09eV and 1.79eV,*** non-UV photodiode with this structure is fabricated on a 6H-SiC(0001)substrate.𝐾J–V𝑊measurements indicate that the device has good rectifying behavior with a rectification ratio up to 200 at 5V,and the turn-on voltage is about *** non-ultraviolet illumination of 0.6W/cm^(2),the device demonstrates a significant photoelectric response with a photocurrent density of 2.9mA/cm^(2)and an open-circuit voltage of ***-ultraviolet operation of the SiC-based photoelectric device is initially realized.

关键词： Schottky heterojunction Si/n

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Synthesis,properties,and self-assembly of 2,3-bis(n-octyl)hexaazatriphenylene

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Chinese Chemical Letters 2013年第6期24卷 453-456页

作者： Zhi-Gang Tao Tian-Guang zhan Tian-You Zhou Xin Zhao zhan-Ting Li Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

A hexaazatriphenylene（HAT） derivative that bears two n-octyl chains was designed and *** photophysical and electrochemical properties have been *** study revealed that it could self-assemble into well-ordered 1D nan... 详细信息

关键词： Hexaazatriphenylene Self-assembly Microsheets nanoribbons

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A Case of Abnormal Bishler-napieralski Cyclization Reaction,Leading to Form Benzyl Oxazole Derivatives

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Chinese Chemical Letters 2001年第3期12卷 195-196页

作者： zhan Zhu LIU Shi Zhi CHEn Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050

A benzyl oxazole compound 3 was obtained with an excellent yield of 90% when n-acetyl-(2'-methoxy-4',5'-methylenedioxy)-phenylalanine methyl ester 1 was refluxed in POCl1/benzene. However, the anticipated product 3,4-dihydrosioquinoline-3-carboxylic acid methyl ester 2 could not be found. The mechanism was discussed in this article.

关键词： n-Acetyl amino acid oxazole Bishler-napieralski reaction.

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nUMERICAL SOLUTIOn OF THE nAVIER-STOKES EQUATIOnS FOR 3-D REGIOn USInG BODY-FITTED COORDInATE SYSTEM

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Journal of Hydrodynamics 1991年第3期3卷 105-109页

作者： Jie-min, zhan Di-ming, zhang Shongskan Univ Guangzhou China

A three-dimensional method is presented for the three dimensional navier-Stokes equations using body-fitted coordinate system. For the convenience of generating the coordinate system, we give some slip-coordinate boundary conditions. numerical results for driven flow in a polar cavity show excellent agreement with the experimental study given by L. Fuchs and n. Tillmark.

关键词： Computers Applications Fluid Mechanics Mathematical Models

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Daifan San intervenes in forkhead box P3 and the interleukin(IL)-23/IL-17A signaling pathway to help prevent and treat primary biliary cirrhosis

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Journal of Traditional Chinese Medicine 2020年第4期40卷 571-583页

作者： zhan Kai Xu Yan Han Mengling Cheng Liangbin The Second Clinical College of Guangzhou University of Chinese Medicine Guangzhou 510000China Department of Internal Medicine Hubei Rongjun HospitalWuhan 430079China Department of Hepatology the Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510000China Department of Hepatology Hubei Provincial Hospital of Chinese MedicineWuhan 430061China

OBJECTIVE:To investigate the mechanism by which Daifan San(DFS)prevents and treats primary biliary cirrhosis(PBC)via the forkhead box P3(FoxP3)and interleukin(IL)-23/IL-17A signaling ***:ninety C57BL/6 mice were randomly divided into the control,model,DFS low-dose,DFS middle-dose,DFS high-dose and ursodeoxycholic acid(UDCA)groups(n=15 per group).A mouse model of PBC was induced using polyinosinic polycytidylic acids(poly I:C).Lymphocyte subset expression in the peripheral blood was analyzed via flow *** inflammatory cytokines and antimitochondrial autoantibody(AMA)levels were detected via enzyme-linked immunosorbent *** expressions and location of typeⅠcollagen,typeⅢcollagen,cytokeratin 19 and FoxP3 in the liver tissue were evaluated via ***3,IL-23 and IL-17 expressions in the peripheral blood and liver tissue were evaluated via real-time polymerase chain reaction and western ***:IL-17,IL-23,IL-8,IL-33,TnF-α,and AMA expressions were significantly increased in the model group and decreased in the DFS and UDCA ***,Treg cell and FoxP3 expressions were significantly decreased in the model group and increased in the DFS and UDCA *** IL-23/IL-17A signaling pathway was closely correlated with chronic inflammation of the bile duct in PBC and functional deletion of Treg cells,leading to reduced FoxP3 levels and mediating the loss of tolerance in ***:DFS may delay the occurrence and relieve the symptoms of PBC by downregulating IL-23/IL-17A signaling pathway expression and upregulating FoxP3 expression.

关键词： Liver cirrhosis,biliary Interleukin-23 Interleukin-17 Signal transduction FoxP3 protein,mouse Daifan San

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Iodomethane as an organocatalyst for the aerobic ortho-selective trifluoromethylation of pyridines

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Science China Chemistry 2023年第1期66卷 133-138页

作者： Jianjin Yu Renqin zhan Chao-Jun Li Huiying Zeng State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou University.Lanzhou 730000China Department of Chemistry FQRNT Centre for Green Chemistry and CatalysisMcGll UniversityMontrealOuebec H3A OB8Canada

Iodomethane is usually used as an electrophilic methylation ***,we report its use as a C1 organocatalyst for the aerobic ortho-selective trifluoromethylation of pyridines in the absence of a transition *** acid(TFA)was employed as an inexpensive,readily available trifluoromethyl *** reaction efficiently produced a variety of trifluoromethylation products,with good functional group ***-containing drug molecules could also be selectively trifluoromethylated for late-stage *** studies showed that iodomethane selectively reacted with the pyridine starting material,rather than the pyridine product,to generate the corresponding n-methylpyridinium *** decarboxylation of trifluoroacetic acid produced a trifluoromethyl anion,which added to the methylpyridinium iodide,and the subsequent aerobic rearomatization led to the generation of the ortho-trifluoromethylated product.

关键词： iodomethane-catalysis trifluoromethylation pyridines transition-metal-free trifluoroacetic acid

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Will the future of shale reservoirs lie in CO2 geological sequestration?

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Science China(Technological Sciences) 2020年第7期63卷 1154-1163页

作者： zhan Jie CHEn zhangXin zhanG Ying ZHEnG ZiGang DEnG Qi School of Petroleum Engineering Xi'an Shiyou UniversityXi'an 710065China Engineering Research Center of Development and Management for Low to Ultra-Low Permeability Oil&Gas Reservoirs in West China Ministry of EducationXi'an Shiyou UniversityXi'an 710065China Department of Chemical&Petroleum Engineering University of CalgaryCalgary T2N1N4Canada natural Gas Engineering Design Department Xi'an Changqing Technology Engineering Co.Ltd.Xi'an 710018China Petroleum Exploration and Development Research Institute PetroChina Changqing Oilfield CompanyXi'an 710018China State Key Laboratory of Oil&Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China

CO2 geological sequestration in a depleted shale gas reservoir is a promising method to address the global energy crisis as well as to reduce greenhouse gas emissions. Though improvements have been achieved by many researchers, the carbon sequestration and enhanced gas recovery(CS-EGR) in shale formations is still in a preliminary stage. The current research status of CO2 sequestration in shale gas reservoirs with potential EGR is systematically and critically addressed in the paper. In addition, some original findings are also presented in this paper. This paper will shed light on the technology development that addresses the dual problem of energy crisis and environmental degradation.

关键词： shale gas reservoir CO2 sequestration EGR indexes criteria for prescreening sorption

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Iron-nickel alloy particles with n-doped carbon “armor” as a highly selective and long-lasting catalyst for the synthesis of nbenzylaniline molecules

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nano Research 2024年第4期17卷 2308-2319页

作者： Gang Wang Longchao Sun Wanyi Liu Haijuan zhan Shuxian Bi College of Chemistry and Chemical Engineering Ningxia UniversityYinchuan 750021China

A scalable strategy for the convenient and rapid preparation of nitrogen-doped carbon-coated iron-based alloy catalysts was *** controlling the type and amount of metal salts in the precursor,various types of nitrogen-doped carbon-coated alloy catalysts can be prepared in a targeted ***_(2)ni2@Cn materials with small particle sizes and relatively homogeneous basic sites showed promising results in the n-alkylation reaction of benzyl alcohol with aniline(optimum yield:99%).It is worth noting that the catalyst can also be magnetically separated and recovered after the reaction,and its performance can be regenerated through simple ***,it was confirmed by kinetic experiments that the activation of C–H at the benzyl alcohol benzylic position is the rate-determining step(RDS).According to density flooding theory calculations,Fe_(2)ni2@Cn catalysts require less energy than other materials(Fe@Cn and ni@Cn)for the RDS(dehydrogenation reaction)*** n-alkylation reactions are more easily carried out on Fe_(2)ni2@Cn catalysts,which may be the reason for the best catalytic activity of Fe-ni alloy *** carbon-coated alloy materials will show great potential in more types of heterogeneous catalysis.

关键词： iron-nickel alloy catalyst n-alkylation reaction magnetic separation reaction path dehydrogenation reaction

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