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Chemical Research in Chinese Universities 2008年第5期24卷 603-607页

作者： CHEN Jing-tao DI You-ying TAN zhi-cheng CHEN San-ping GAO sheng-li Department of Chemistry Shaanxi Educational College Xi＇an 710061 P. R. China College of Chemistry and Chemical Engineering Liaocheng University Liaocheng 252059 P. R. China Department of Chemistry Northwest University Xi＇an 710069 P. R. China

low-temperature heat capacities of the solid compound Zn（C4H7O5）2（s） were measured in a temperature range from 78 to 374 K, with an automated adiabatic calorimeter. A solid-to-solid phase transition occurred in the temperature range of 295？322 K. The peak temperature, the enthalpy, and entropy of the phase transition were determined to be （316.269±1.039） K, （11.194±0.335） kJ？mol-1, and （35.391±0.654） J？K-1？mol-1, respectively. The experimental values of the molar heat capacities in the temperature regions of 78？295 K and 322？374 K were fitted to two polynomial equations of heat capacities（Cp,m） with reduced temperatures（X） and [X = f（T）], with the help of the least squares method, respectively. The smoothed molar heat capacities and thermodynamic functions of the compound, relative to that of the standard reference temperature 293.15 K, were calculated on the basis of the fitted polynomials and tabulated with an interval of 5 K. In addition, the possible mechanism of thermal decomposition of the compound was inferred by the result of TG-DTG analysis.

关键词： Zn(C4H7O5)2(s) Adiabatic calorimetry low-temperature heat capacity Solid-to-solid phase transition Thermodynamic property TG-DTG

Preparation of Al-Zn-Mg-Cu alloy semisolid slurry through a water-cooled serpentine pouring channel

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China Foundry 2019年第1期16卷 31-39页

作者： Wen-zhi Zhu Wei-min Mao Qing-song Wei Chen Hui Yu-sheng Shi State Key laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

The semisolid slurry of Al-Zn-Mg-Cu alloy was prepared through a self-designed water-cooled copper serpentine pouring channel(WSPC) machine. Influences of pouring temperature, the number of turns and the cooling water flow rate on the microstructure of the semisolid Al-Zn-Mg-Cu alloy slurry were investigated. The results show that the semisolid Al-Zn-Mg-Cu alloy slurry with satisfactory quality can be generated by the WSPC when the pouring temperature is in the range between 680 ℃ and 700 ℃. At a given pouring temperature, the average grain size of primary α-Al decreases and the shape factor increases with the increase of the number of turns. When the cooling water flow rate is 450 l·h^(-1), the obtained semisolid slurry is optimal. During the preparation of the semisolid Al-Zn-Mg-Cu alloy slurry with low superheat pouring, the alloy melt has mixed inhibition and convection flow characteristics by "self-stirring". When the alloy melt flows through the serpentine channel, the chilling effect of the inner wall of the channel, the convection and mixed inhibition of the alloy melt greatly promote the heterogeneous nucleation and grain segregation. This effect destroys the dendrite growth mode under traditional solidification conditions, and the primary nuclei gradually evolve into spherical or nearspherical grains.

关键词： Al-Zn-Mg-Cu Alloy semisolid slurry water-cooled serpentine channel primary α-Al

Study on Immobilized lipase Catalyzed Transesterification Reaction of Tung Oil

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Agricultural Sciences in China 2006年第11期5卷 859-864页

作者： XU Gui-zhuan ZHANG Bai-liang lIU sheng-yong YUE Jian-zhi Key laboratory of Renewable Energy of Ministry of Agriculture/Mechanical and Electrical Engineering College Henan Agricultural University Zhengzhou 450002 P.R.China

The transesterification reaction conditions of tung oil with methanol have been studied in this article, with immobilized lipase NOVO435 as catalyst. The response surface methodology was used to optimize the transesterification reaction of tung oil in a nonsolvent system. The optimal conditions were rotation rate 200 r/min, molar ratio of methanol to oil 2.2： l, reaction temperature 43℃, and the catalyst amount 14% （based on the weight of oil）. After reacting for 18 h, 67.5% of the oil was converted to its corresponding methyl esters （the theoretical ester conversion was 73.3%）. The lipase was washed by organic solvents after each reaction and was reused again. The esters conversion of tung oil was decreased by 6% after the lipase was reused for 120 h. The theoretical amount of methanol was added in two steps, 85% ester conversion was obtained after 36 h of reaction （theoretical ester conversion was 100%）. The molar ratio of methanol to oil, the catalyst amount, the reaction temperature, and reaction time were all highly significant factors, and there was a relative significant interaction between every two factors.

关键词： nonsolvent transesterification biodiesel lipase tung oil

Estimation of Semi-Varying Coefficient Model with Surrogate Data and Validation Sampling

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Acta Mathematicae Applicatae Sinica 2013年第3期29卷 645-660页

作者： Ya-zhao l Ri-quan ZHANG Zhen-sheng HUANG Department of Statistics East China Normal University Institute of Operational Research and Cybernetics Hangzhou Dianzi University Department of Mathematics Shanxi Datong University School of Science Nanjing University of Science and Technology

In this paper, we investigate the estimation of semi-varying coefficient models when the nonlinear covariates are prone to measurement error. With the help of validation sampling, we propose two estimators of the parameter and the coefficient functions by combining dimension reduction and the profile likelihood methods without any error structure equation specification or error distribution assumption. We establish the asymptotic normality of proposed estimators for both the parametric and nonparametric parts and show that the proposed estimators achieves the best convergence rate. Data-driven bandwidth selection methods are also discussed. Simulations are conducted to evaluate the finite sample property of the estimation methods proposed.

关键词： asymptotic normality profile likelihood measurement error validation sampling semi-varying coefficient model

Effect of Annealing Temperature on Recrystallization Behavior of Cold Rolled Ti-Microalloyed Steel

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Journal of Iron and Steel Research International 2013年第9期20卷 105-110页

作者： HUO Xiang-dong MAO Xin-ping l sheng-xia School of Material Science and Engineering Jiangsu University Guangzhou Zhujiang Steel Co. Ltd.

In order to develop cold rolled Ti-microalloyed steel strips, the effects of annealing temperature on recrys-tallization behavior of experimental steel were researched by optical microscopy （OM）, transmission electron micros-copy （TEM） and Vickers hardness test. The annealing treatment could be divided into three distinct stages： recovery, recrystallization and grain growth. Reerystallization took place from 933 to 1033 K, during which a large number of recrystallized grains appear and hardness drops sharply. The morphology and size of TiN particles nearly remained unchanged at different stages of processing. With increasing annealing temperature, nanometer precipitates coarsened and the dislocation density was significantly reduced. In comparison with annealing time, annealing temperature was more crucial for recrystallization of cold rolled Ti microalloyed steel. It could be concluded that the pinning force of nanometer particles on dislocations increased the recrystallization temperature. At higher annealing temperature, re crystallization took place because of precipitates coarsening caused by Ostwald ripening.

关键词： annealing temperature recrystallization Ti-microalloyed steel titanium earbide dislocation

Inheritance of Powdery Mildew Resistance in Cucumber (Cucumis sativus l.) and Development of an AFlP Marker for Resistance Detection

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Agricultural Sciences in China 2007年第11期6卷 1336-1342页

作者： ZHANG Su-qin GU Xing-fang ZHANG sheng-ping ZOU zhi-rong Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China Agricultural College Guizhou University Guiyang 550025 P.R.China College of Horticulture Northwest A ＆ F University Yangling 712100 P.R.China

Cucumber powdery mildew is one of the most destructive diseases of cucumber throughout the world. In the present study, inheritance of powdery mildew resistance in three crosses, and linkage of resistance with amplified fragment length polymorphism （AFlP） markers are studied to formulate efficient strategies for breeding cultivars resistant to powdery mildew. The joint analysis of multiple generations and AFlP technique has been applied in this study. The best model is the one with two major genes, additive, dominant, and epistatic effects, plus polygenes with additive, dominant, and epistatic effects （E-l-0 model）. The heritabilities of the major genes varied from 64.26% to 97.82%, and susceptibility was incompletely dominant for the two major genes in the three crosses studied. The additive effects of the two major genes and the dominant effect of the second major gene were high, and the epistatic effect of the additive-dominant between the two major genes was the highest in cross I . In cross II, the absolute value of the additive effect, dominant effect, and potential ratio of the first major gene were far higher than those of the second major gene, and the epistatic effect of the additive-additive was the highest. The genetic parameters of the two major genes in cross III were similar to those in cross II. Correlation and regression analyses showed that marker E25/M63-103 was linked to a susceptible gene controlling powdery mildew resistance. The marker could account for 19.98% of the phenotypic variation. When the marker was tested on a diverse set of 29 cucumber lines, the correlation between phenotype and genotype was not significant, which suggested cultivar specialty of gene expression or different methods of resistance to powdery mildew. The target DNA fragment was 103 bp in length, and only a small part was found to be homologous to DNA in the other species evaluated, which indicated that it was unique to the cucumber genome.

关键词： cucumber (Cucumis sativus l.) powdery mildew resistance inheritance amplified fragment lengthpolymorphism (AFlP) molecular marker

Highly Stretchable and Conductive Hybrid Fibers for High-performance Fibrous Electrodes and All-solid-state Supercapacitors

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Chinese Journal of Polymer Science 2020年第5期38卷 531-539,I0007页

作者： Gui-Qing Wu Xin-Yu Yang Jia-Hui li Nan sheng Cheng-Yi Hou Yao-Gang li Hong-zhi Wang State Key laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China School of Materials Science and Engineering Nanyang Technological University639798Singapore

The development of lightweight,flexible,and stretchable energy storage systems is essential for state-of-the-art electronic *** propose a new and broad strategy to fabricate a stretchable and conductive GO/CNTs-TPU fiber electrode by direct wet spinning,from which a flexible fibrous supercapacitor is *** fibrous electrode exhibits a high strength of 11.68 MPa,high conductivity of 342 S/cm,and high specific capacitances(21.8 mF/cm,36.45 F/cm^3,and 95 F/g).The specific capacitance of the assembled all-solid-state hybrid fiber-shaped supercapacitor reaches 14.3 F/cm^*** 5000 charge-discharge cycles,97%of the capacitance of the hybrid supercapacitor is *** high-strength electrochemical electrode materials could be potential candidates for applications in practical and large-scale energy storage systems and textile clothes.

关键词： Graphene Carbon nanotubes Thermoplastic polyurethane Supercapacitor Flexibility

Synthesis and Crystal Structure of a Novel Manganese Coordination Polymer: 2,5-Bis(4-pyridyl)-3,4-diaza-2,4-hexadiene

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Chinese Journal of Structural Chemistry 2007年第2期26卷 219-223页

作者： CHEN Man-sheng DENG Yi-Fang ZHANG Chun-Hua KUANG Dai-zhi FENG Yong-lan PENG Yun-lin Department of Chemistry and Materials Science Hen gyan g Normal University Hen gyan g 421008 China

A new manganese coordination polymer 1, [Mn（H2O）4（l）]n（ClO4）2n.2nH2O.3nl （l = 2,5-bis（4-pyridyl）-3,4-diaza-2,4-hexadiene）, has been synthesized and structurally characterized. The crystal structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group Pn with a = 13.9176（8）, b = 15.4754（9）, c = 15.9670（9） A, β = 99.5010（10）°, V = 3391.8（3） ]k3, Z = 2, C56H68C12MnN16O14, Mr= 1315.10, Dc = 1.288 g/cm^3,μ = 0.344 mm^-1, F（000） = 1374, R = 0.0733 and wR = 0.2035. In the crystal the manganese atom is six-coordinated by two nitrogen atoms from 2,5-bis（4-pyridyl）-3,4-diaza-2,4-hexadiene and four oxygen atoms from water molecules, completing an octahedral geometry. The title complex exhibits a novel supramolecular layer architecture sustained by the concurrence of coordination bonds, hydrogen bonds, and π-π stacking interactions.

关键词： manganese complex Schiff bases crystal structure

Geographic variation in photoperiodic diapause induction and diapause intensity in Sericinus montelus （lepidoptera Papilionidae）

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Insect Science 2012年第3期19卷 295-302页

作者： Xiao-Ping Wang Qiu-sheng Yang Peter Dalin Xing-Miao Zhou zhi-Wen luo Chao-liang lei Hubei Insect Resources Utilization and Sustainable Pest Management Key laboratory College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina Department of Ecology Swedish University of Agricultural SciencesUppsalaSweden College of life Science Jiamusi UniversityJiamusiHelongjiang ProvinceChina

Due to the risk of extinction and ornamental value of the swallowtail butterfly, Sericinus montelus Gray （lepidoptera： Papilionidae） in China, knowledge about local adaptations is important for the conservation and economical utilization of the species. In the present study, photoperiodie diapause induction and diapause intensity of S. montelus populations from Jiamusi （46°37＇N）, Beijing （40° 15＇N）, Zibo （36°48＇N）, Fangxian （32°36＇N）, Wuhan （30°33＇N） and Huaihua （27°33＇N） were characterized at 25℃. logistic regression analysis revealed a significant population x hours of light interaction, confirming that photoperiodic responses varied among populations. The critical photoperiod was positively correlated with latitude and increased toward the north at a rate of about 1 h for each 6.67 degrees of latitude. Survival analyses indicated that survival time of diapausing pupae before adult eclosion differed significantly among populations at 25℃ and 16 ： 8 l ＂D h. The mean duration of pupal diapause was also positively correlated with latitude. Our study reveals geographic variation in the critical photoperiod for diapause induction and in diapause intensity of S. montelus. These results provide useful information for our general understanding about seasonal adaptation in insects and may also be used to predict how geographic populations respond to climate warming.

关键词： critical photoperiod duration of diapause geographic population pupal diapause Sericinus montelus

Two new isoflavonoids from the rhizomes of Belamcanda chinensis

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Chinese Chemical letters 2007年第6期18卷 694-696页

作者： zhi Jun Song Fan luo Yan Zhou Bin Ru Bai Shu lin Peng li sheng Ding Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041 China College of life Science and Technology Southwest University for Nationalities Chengdu 610041 China

Two new isoflavonoids, 6-methoxy-5,7,8,4′-tetrahydryoxyisoflavone (1) and 4′-methoxy -5,6-dihydroxyisoflavone-7-O-β-d-glucopyranoside (2), were isolated from the rhizomes of Belamcanda chinensis (l.) DC. Their stru... 详细信息

关键词： Belamcanda chinensis Isoflavanoid 6-Methoxy-5,7,8,4′-tetrahydryoxyisoflavone 4′-Methoxy-5,6-dihydroxyisoflavone-7-O-β-d-glucopyranoside