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Effect of cis/trans molecular structures on pyrolysis performance and heat sink of decalin isomers

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Frontiers of Chemical Science and Engineering 2024年第1期18卷 51-60页

作者： Qing Liu Kang Xue Tinghao jia Zhouyang Shen Zehao Han Lun Pan Ji-Jun zou Xiangwen Zhang Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovative Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhejiang Institute of Tianjin University Ningbo 315201China

Decalin is considered as an important compound of high-energy-density endothermic fuel,which is an ideal on-board coolant for thermal management of advanced ***,decalin contains two isomers with a tunable composition,and their effects on the pyrolysis performance,such as the heat sink and coking tendency have not been ***,we investigated the pyrolysis of decalin isomers,i.e.,cis-decalin,trans-decalin and their mixtures(denoted as mix-decalin),in order to clarify the effects of the cis-/trans-structures on the pyrolysis performance of decalin *** pyrolysis results confirmed that conversion of the tested fuels(600–725℃,4 MPa)decreased in the order cis-decalin>mix-decalin>*** analyses of the pyrolysis products were used to compare the product distributions from cis-decalin,mix-decalin and trans-decalin,and the yields of some typical components(such as cyclohexene,1-methylcyclohexene,benzene and toluene)showed significant differences,which could be ascribed to deeper cracking of ***,the heat sinks and coking tendencies of the decalins decreased in the order cis-decalin>mix-decalin>*** work demonstrates the relationship between the cis/trans structures and the pyrolysis performance of decalin,which provides a better understanding of the structure-activity relationships of endothermic hydrocarbon fuels.

关键词： endothermic fuel decalin pyrolysis heat sink molecular structure

Synthesis of ultralong Si_3N_4 nanowires by a simple thermal evaporation method

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Rare Metals 2013年第2期32卷 186-190页

作者： Wen-Qi Wang Xiao-Ping zou Nan-jia Zhou Guang Zhu Gui-Ying Wang Zhen-Sheng Peng Anhui Key Laboratory of Spintronics and Nano-materials (Cultivating Base) Suzhou University Research Center for sensor Technology Beijing Key Laboratory for SensorBeijing Information Science and Technology University Department of Materials Science and Engineering Northwestern University Structure Research Laboratory University of Science and Technology of China

Largescale vaporsolid synthesis of ultralong silicon nitride （Si3N4） nanowires was achieved by using simple thermal evaporation of mixture powders of active carbon and monoxide silicon. The products were charac terized by Xray diffraction, scanning electron microscopy, energydispersive Xray spectroscopy, and transmission electron microscopy. The results suggest that the silicon nitride nanowires have a smooth surface, with lengths of up to several hundreds of microns and diameters of 100300 nm. A detailed study of both the chemical and structural composition was performed. Such ultralong sil icon nitride nanowires demonstrate potential applications as materials for constructing nanoscale devices and as reinforcement in advanced composites.

关键词： Si3N4 nanowires Ultralong Thermal evaporation

Water quality evaluation of Haihe River with fuzzy similarity measure methods

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Journal of Environmental Sciences 2013年第10期25卷 2041-2046页

作者： Xiaojing Wang Zhihong zou Hui zou School of Economic and Management Beihang University Department of Applied Mathematics College of ScienceChina Agricultural University

Fuzzy similarity measures, which are used to judge the closeness of two fuzzy sets, are presented to evaluate the water quality of the Haihe River. Based on the membership functions and coefficient of variation as the weights, four fuzzy similarity measures （including Lattice similarity measure, Hamming similarity measure, Euclidean similarity measure and the max-min similarity measure） are used to classify the 299 samples into the proper water quality standard ranks. The results are compared with the traditional distance discriminant methods. The calculation of two traditional distance discriminant methods （both Euclidean distance and absolute value distance） is also based on the use of coefficients of variation as the weights. Without the Lattice similarity measure, for this method loses some information, the correct assignment of samples classified into the same water quality ranks is 75.92% with the other three similarity measures and two distance discriminant methods. This result shows the reliability of the five methods. Only considering the three similarity measures, there were only 1.01% of the samples that did not classify to the same ranks, while the corresponding ratio of the two distance discriminant methods was 5.69%. The results of leave-one-out cross validation show that more than 88% of the samples are classified to the proper ranks, which demonstrates that the similarity measures are suitable to evaluate the water quality of the Haihe River.

关键词： similarity measure distance discriminant coefficient of variation membership function

Solid-liquid state pressure bonding of Si_3N_4 ceramics with aluminum based alloys and its mechanism

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中国有色金属学会会刊：英文版 2001年第2期11卷 177-182页

作者：邹贵生吴爱萍任家烈 Department of Mechanical Engineering Tsinghua University

Solid liquid state pressure bonding of Si 3N 4 ceramics with aluminum based alloys, which contain a small amount of intermetallic compounds Al 3Ti or Al 3Zr, was investigated. With this new method, the heat resistant properties of the bonding zone metal are improved, and the joints’ strengths at high temperature is increased. The joints’ shear strength at room temperature and at 600 ℃ reach 126～133 MPa and 32～34 MPa, respectively, with suitable bonding pressure. The reaction between aluminum and Si 3N 4 ceramics, which produces Al Si N O type compounds is the dominant interfacial reaction, while the reactions between the second active element Ti or Zr in the aluminum based alloys and Si 3N 4 ceramics also occur to some extend. [

关键词： solid liquid state pressure bonding Si 3N 4 ceramics intermetallic compounds high temperature properties

Construction and detection of expression vectors of microRNA-9a in BmN cells

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第7期12卷 527-533页

作者： Yong HUANG Quan zou Sheng-peng WANG Shun-ming TANG Guo-zheng ZHANG Xing-jia SHEN Key Laboratory of Silkworm and Mulberry Genetic Improvement Ministry of Agriculture Jiangsu University of Science and Technology Zhenjiang 212018 China School of lnformation Science and Technology Xiamen University Xiamen 361005 China Sericultural Research Institute Chinese Academy of Agricultural Sciences Zhenjiang 212018 China Animal Science and Technology College Henan University of Science and Technology Luoyang 471003 China

MicroRNAs (miRNAs) are small endogenous RNAs molecules,approximately 21–23 nucleotides in length,which regulate gene expression by base-pairing with 3′ untranslated regions (UTRs) of target ***,the functions of only a few miRNAs in organisms are ***,the expression vector of artificial miRNA has become a promising tool for gene function ***,a method for easy and rapid construction of eukaryotic miRNA expression vector was *** cytoplasmic actin 3 (A3) promoter and flanked sequences of miRNA-9a (miR-9a) precursor were amplified from genomic DNA of the silkworm (Bombyx mori) and was inserted into pCDNA3.0 vector to construct a recombinant *** enhanced green fluorescent protein (EGFP) gene was used as reporter *** Bombyx mori N (BmN) cells were transfected with recombinant miR-9a expression plasmid and were harvested 48 h post *** RNAs of BmN cells transfected with recombinant vectors were extracted and the expression of miR-9a was evaluated by reverse transcriptase polymerase chain reaction (RT-PCR) and Northern *** showed that the recombinant miR-9a vector was successfully constructed and the expression of miR-9a with EGFP was detected.

关键词： miRNA-9a (miR-9a) EGFP gene Bombyx mori N (BmN) Cells Expression vector

Review on the Relationship Between Liquid Aerospace Fuel Composition and Their Physicochemical Properties

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Transactions of Tianjin University 2021年第2期27卷 87-109页

作者： Xiaoyu Wang Tinghao jia Lun Pan Qing Liu Yunming Fang Ji-Jun zou Xiangwen Zhang Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovative Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Department of Chemical Engineering National Energy R&D Research Center for Biorefi neryBeijing University of Chemical TechnologyBeijing 100029China

The development of advanced air transportation has raised new demands for high-performance liquid hydrocarbon ***,the measurement of fuel properties is time-consuming,cost-intensive,and limited to the operating *** physicochemical properties of aerospace fuels are directly infl uenced by chemical ***,a thorough investigation should be conducted on the inherent relationship between fuel properties and composition for the design and synthesis of high-grade fuels and the prediction of fuel properties in the *** work summarized the eff ects of fuel composition and hydrocarbon molecular structure on the fuel physicochemical properties,including density,net heat of combustion(NHOC),low-temperature fl uidity(viscosity and freezing point),fl ash point,and thermal-oxidative *** correlations and predictions of fuel properties from chemical composition were ***,we correlated the fuel properties with hydrogen/carbon molar ratios(n H/C)and molecular weight(M).The results from the least-square method implicate that the coupling of H/C molar ratio and M is suitable for the estimation of density,NHOC,viscosity and eff ectiveness for the design,manufacture,and evaluation of aviation hydrocarbon fuels.

关键词： Liquid hydrocarbon fuel Physicochemical properties Composition Molecular structure Fuel properties correlation

Two-Photon Atomic Coherence Effect of Transition 5S_(1/2)-5P_(3/2)-4D_(5/2)(4D3/2) of 85Rb atoms

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Chinese Physics Letters 2012年第2期29卷 86-88页

作者： DING Dong-Sheng ZHOU Zhi-Yuan SHI Bao-sen zou Xu-Bo GUO Guang-Can Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026

We experimentally observe the counterintuitive absorption peaks in the transition spectra of 5S_(1/2)-5P_(3/2)-4D_(5/2) and 5S_(1/2)-5P_(3/2)-4D_(3/2) in a hot 85Rb *** spectra are very different from the spectra observed via double resonance optical pumping or electromagnetically induced transparency in the same *** absorption peaks are from electromagnetically induced absorption due to the two-photon atomic coherence *** also investigate the relations between these peaks and the powers of the coupling laser and the probe laser experimentally.

关键词： effect absorption Transition

Recasting theory of elasticity with micro-finite elements

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Acta Mechanica Sinica 2015年第5期31卷 679-684页

作者： Wennan zou Institute for Advanced Study Nanchang University

In the classical theory of elasticity,a body is initially modeled as a homogeneous and dense assemblage of constituent ＂material particles＂.The kernel concept of elastic deformation is the displacement of the particle that associates the current configuration with the reference *** this paper,we exploit an alternative constituent ＂micro-finite element＂,and use the stretch of the element as the essential quality to recast the theory of *** should be realized that such a treatment means that the elastic body can be modeled as a finite covering of elements and consequently characterized by a *** recasting of the elasticity theory becomes more feasible for dealing with defects and topological evolution.

关键词： Micro-finite element Stretch Displacement Relative rotation Compatibility condition

Fractal Study on Raceway Boundary

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Journal of Iron and Steel Research International 2011年第5期18卷 16-19页

作者： DI Zhan-xia LUO Zhi-guo HAN Yan-zhi zou Zong-shu LI jia-xin School of Materials and Metallurgy Northeastern UniversityShenyang 110004LiaoningChina School of Metallurgy and Resources Anhui University of TechnologyMa′anshan 243002AnhuiChina

The raceway has been studied extensively both theoretically and experimentally. The raceway boundary is coarse and fragmentary,but all of previous studies are based on Euclidean geometry,which regards the dimension of raceway as an integer. The fractal method of calculating raceway size,which describes boundary with extremely irregular or fragmentary characteristic,is brought forward in physical model. The fractal theory is used to calculate the fractal dimension of raceway boundary and the precise surface area of ellipsoidal raceway boundary. The result shows that the surface area based on fractal is larger than that based on Euclidean. And the surface area increases with the rise of blowing rate.

关键词： raceway boundary physical simulation fractal