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composition－THERMODYNAMIC　PROPERTY　RELATIONSHIPS　FOR　TERNARY　POLAR　MIXTURE　VIA　NEURAL　NETWORKS

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Chinese Chemical Letters 1996年第7期7卷 651-652页

作者： Yi Lin CAO Shu Ting YANG Qing Zhang LU(Department of Chemistry,Henan Normal University, Henan, Xinxiang, 453002) Department of Chemistry Henan Normal University Henan Xinxiang 453002

Artificial neural network(ANN) models have been employed to the calculations ofdensities and excess molar volumes of water+methanol+ethylene glycol ternary system at different temperatures. The results were satisfactory comparing with the experimental values. The method wasconvenient in operation, rapid in calculation and easy in extending to multicomponent systems.

关键词： VIA MIXTURE NEURAL NETWORKS POLAR composition

composition and Distribution of Planktonic Ciliates in the Southern South China Sea During Late Summer： Comparison Between Surface and 75 m Deep Layer

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Journal of Ocean University of China 2016年第1期15卷 171-176页

作者： LIU Huaxue SHEN Pingping LI Chunhou CHEN Zuozhi QI Zhanhui HUANG Honghui Guangdong Provincial Key Laboratory of Fishery Ecology and Environment Key Laboratory of South China Sea Fishery Resources Development and Utilization of Ministry of Agriculture South China Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Guangzhou 510300 P. R. China Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 P. R. China

Ciliates are very important components in most marine ecosystem. They are trophic link between the microbial food web and grazing food chain. In this study, ciliates were collected from 11 sites in the southern South China Sea （SCS） during August 25 to September 28, 2011. Their composition and distribution at the surface and 75m deep depth of the ocean were studied. A total of 30 species belonging to 22 genera were identified, and 22 species of 15 genera were Tintinnids. Eutintinnusfraknoii and E. stramentus were the most common species. The other dominants were strombidiids ciliates including Strombidium conicum and S. globosaneum, which were followed by the tide form, Mesodinium pulex. Ciliates abundance ranged from 46 indL-1 to 368 indL-1 in the open sites, 46-368indL-1 at surface and 73-198indL-1 at 75m deep layer. In the Yongshu reef, ciliates abundance ranged from 167indL-1 to 365 ind L-1 in the water colunm, similar to that in Sanya coral reef waters. Ciliates composition showed obvious difference between surface and 75m deep layer at station S2 （P〈0.05）, while no similar result was observed at other sites. At 75m deep layer, salinity was negatively related to mixed layer depth （P〈 0.05）, but positively to chlorophyll a concentration （P〈 0.05）, indicating that the change of vertical mixing in water column influenced vertical distribution of ciliates in the southern SCS.

关键词： South China Sea Yongshu Reef ciliates composition

Readout electronics of a prototype time-of-flight ion composition analyzer for space plasma

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Nuclear Science and Techniques 2018年第4期29卷 98-107页

作者： Di Yang Zhe Cao Xin-Jun Hao Yi-Ren Li Shu-Bin Liu Chang-Qing Feng Qi An State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China Division of Space Physics University of Science and Technology of China Hefei 230026 China CAS Key Laboratory of Geospace Environment Hefei 230026 China

Readout electronics is developed for a prototype time-of-flight(TOF) ion composition spectrometer for in situ measurement of the mass/charge distributions of major ion species from 200 to 100 ke V/e in space *** utilizing a constant fraction discriminator(CFD) and time-to-digital converter(TDC), challenging dynamic range measurements were performed with high time resolution and event rates. CFD was employed to discriminate the TOF signals from the micro-channel plate and channel electron multipliers. TDC based on the combination of counter and OR-gate delay chain was designed in a highreliability flash field programmable gate array. Owing to the non-uniformity of the delay chain, a correction algorithm based on integral nonlinearity compensation was implemented to reduce the time uncertainty. The test results showed that the electronics achieved a low timingerror of < 200 ps in the input range from 35 to 500 m V for the CFD, and a time resolution of ～550 ps with time uncertainty < 180 ps after correction and a time range of6.4 ls for the TDC. The TOF spectrum from an electron beam experiment of the impacting N_2 gas further indicated the good performance of this readout electronic.

关键词： Space plasma Ion composition analyzer Readout electronics Constant fraction discriminator Time-to-digital converter

EFFECTS OF MOLECULAR SIZE AND COMBINATION RULE ON LOCAL composition

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Chinese Journal of Chemical Engineering 1996年第4期4卷 86-92页

作者：袁红高广图曾晓成 University of Nebraska-Lincoln 美国

1 INTRODUCTIONThe concept of local composition(the local mole fraction of one component aroundanother),which is different from the bulk mole fraction,has been successfully used todevelop thermodynamic models for liquid mixtures,which include Guggenheim’squasi-chemical theory [1],Wilson’s equation [2],nonrandom two-liquid(NRTL)equa-tion [3] and the UNIQUAC equation [4,5].The basis of all these models is that the dif-

关键词： computer simulation local composition mixing rule molecular interaction

Discrete composition control of two-dimensional morphologic all-inorganic metal halide perovskite nanocrystals

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Journal of Energy Chemistry 2021年第8期30卷 257-275,I0006页

作者： Andrew Hunter Davis Weiwei Zheng Department of Chemistry Syracuse University13244 SyracuseUnited States

Metal halide perovskite nanocrystals(NCs)exhibit impressive optical and electronic properties,making them an important class of functional materials with promising applications in solar cells,light emitting diodes(LEDs),photodetectors,and *** addition to the widely studied 0-dimensional(0 D)metal halide perovskite NCs,such as nanocubes,low dimensional perovskites,such as 2 D all-inorganic perovskite(AIP)NCs,subsist with directionally relevant quantum *** anisotropic NCs have the propensity to exhibit interesting optoelectronic properties that are exceedingly difficult to introduce into 0 D systems,yet as of late are largely *** this review,we discuss the recent synthetic progress of 2 D all-inorganic metal halide perovskite NCs with ABX3 ***,we highlight the discrete composition control of the cations(A and B sites)and anions(X site)by dopant incorporation and alloying in 2 D metal halide perovskite *** will also discuss more complex perovskite crystal structures,such as Ruddlesden-Popper double perovskites,and compare these materials to 0 D perovskite ***,our work culminates in the future interests and perspectives of this field with a focus on the wide applicability of 2 D systems and the large variance in structure capable with discrete compositional tuning.

关键词： All-inorganic perovskites Two-dimensional nanocrystals composition Doping Alloying Ion exchange

Identification of the bound residue composition derived from ^(14)C-labeled chlorsulfuron in soil by using LC-MS and isotope tracing method

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Journal of Environmental Sciences 2004年第1期16卷 73-78页

作者： YEQing-fu WUJian-min SUNJin-he InstituteofNuclear-AgriculturalScience ZhejiangUniversityHangzhou310029China

A new method for extracting the bound residue(BR) derived from 14 C-labeled chlorsulfuron in soils was developed, and the technique of combining LC-MS with isotope tracing method was subsequently applied to identify the composition of the 14 C-BR in a loamy Fluvent derived from marine deposit. The results showed that the 14 C-[2-amino-4-methoxyl-6-methyl-1,3,5]-triazine, 14 C-[2-amino-4-hydroxyl-6-methyl-1,3,5]-triazine and 14 C-chlorsulfuron parent compound constituted the main composition of the 14 C-BR derived from 14 C-labeled chlorsulfuron in the soil. The radioactive ratio of three compounds accounted for 39.8%, 35.4% and 17.9% of total recovered radioactivity, respectively. However, a small amount(3.6% of total recovered radioactivity) of the complex of 14 C-[2-amino-4-hydroxyl-6-methyl-1,3,5]-triazine might have existed in the 14 C-BR in association with an unknown soil substrate. 2-chlorobenzenesulfonamide was also detected to be one of the components of the BR. The results could well explain the mechanism of phytotoxicity caused by the BR derived from chlorsulfuron in soil. In addition, the mechanism of BR formation in soil was also discussed in details.

关键词： bound residue chlorsulfuron composition identification soil

Effects of particle composition and environmental parameters on catalytic hydrodechlorination of trichloroethylene by nanoscale bimetallic Ni-Fe

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Journal of Environmental Sciences 2014年第5期26卷 1162-1170页

作者： Jianjun Wei Yajing Qian Wenjuan Liu Lutao Wang Yijie Ge Jianghao Zhang Jiang Yu Xingmao Ma Department of Environmental Science and Engineering Beijing University of Chemical Technology Department of Civil and Environmental Engineering Southern Illinois University Carbondale

Catalytic nickel was successfully incorporated into nanoscale iron to enhance its dechlorination efficiency for trichloroethylene （TCE）, one of the most commonly detected chlorinated organic compounds in groundwater. Ethane was the predominant product. The greatest dechlorination efficiency was achieved at 22 molar percent of nickel. This nanoscale Ni-Fe is poorly ordered and inhomogeneous; iron dissolution occurred whereas nickel was relatively stable during the 24-hr reaction. The morphological characterization provided significant new insights on the mechanism of catalytic hydrodcchlorination by bimetallic nanoparticles. TCE degradation and ethane production rates were greatly affected by environmental parameters such as solution pH, temperature and common groundwater ions. Both rate constants decreased and then increased over the pH range of 6.5 to 8.0, with the minimum value occurring at pH 7.5. TCE degradation rate constant showed an increasing trend over the temperature range of 10 to 25℃. However, ethane production rate constant increased and then decreased over the range, with the maximum value occurring at 20℃, Most salts in the solution appeared to enhance the reaction in the first half hour but overall they displayed an inhibitory effect. Combined ions showed a similar effect as individual salts.

关键词： nanoscale Ni-Fe trichloroethylene hydrodechlorination catalytic dechlorination composition environmental parameters

Effects of seagrass leaf litter decomposition on sediment organic carbon composition and the key transformation processes

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Science China Earth Sciences 2017年第12期60卷 2108-2117页

作者： LIU SongLin JIANG ZhiJian DENG YiQin WU YunChao ZHAO ChunYu ZHANG JingPing SHEN Yuan HUANG XiaoPing Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of OceanologyChinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences South China Sea Fisheries Research Institute Chinese Academy of Fishery Sciences

Seagrass leaf litters are an important source of sediment organic carbon(SOC). However, the mechanisms of seagrass leaf litter decomposition influencing SOC composition and the key transformation processes remain unknown. We performed a laboratory chamber experiment to compare the labile organic carbon(OC) composition and the enzyme activities governing SOC transformation between the seagrass group(seagrass leaf litter addition) and the control group. The results showed that the seagrass leaf litter decomposition significantly elevated the salt-extractable carbon(SEC) content and the SEC/SOC. Additionally,the levels of invertase, polyphenol oxidase, and cellulase in the seagrass leaf litters addition group were generally higher than in the control group, which could elevate recalcitrant OC decomposition. Following 24 days incubation, addition of seagrass leaf litter increased the amount of CO_2 released, but decreased the SOC content. Therefore, seagrass leaf litter decomposition leached abundant dissolved OC, which enhanced the activity and transformation of SOC.

关键词： Seagrass leaf litter Sediment organic carbon composition Enzyme activities

Control of mould level fluctuation through the modification of steel composition

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International Journal of Minerals,Metallurgy and Materials 2013年第2期20卷 138-145页

作者： Yang Li Xiao-huan Zhang Peng Lan Jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

Periodic mould level fluctuation （MLF） during slab casting is a bottleneck for upgrading the surface quality and casting speed especially for hypoperitectic （HP） or ultralow carbon steels. The uneven growth of the initially solidified shell is verified to be one of the important inducements to MLF due to related unsteady bulging in the secondary cooling zone. It is shown that the solidification mode of steels and the contraction behavior can be modified through chemical composition optimization within given composition limits, For high strength low alloy （HSLA） steels, the actual peritectic points calculated by Thermo-Calc software may change remarkably with the slight variations of alloying element contents. Accordingly, the narrow limit of chemical composition of HP steels through optimization is proven to be one of the effective factors to control the popular MLF phenomenon during slab casting.

关键词： low carbon steel continuous casting solidification composition optimization