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Studies on the Quantitative Structure-activity Relationship of Substituted Biphenyls by Density Function Theory (DFT)

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Chinese Journal of Structural Chemistry 2007年第2期26卷 229-233页

作者： han Xiang-yun ZHENG Qing Department of Chemical Engineering YanchengInstitute of Technology Jiangsu 224003 China

Geometrical configurations of 16 substituted biphenyls were computed at the B3LYP/6-311G^＊＊ level with Gaussian 98 program. Based on linear solvation energy theory, lgKow as well as the structural and thermodynamic parameters obtained at this level was taken as theoretical descriptors, and corresponding equation predicting the toxicity of Daphnia magna （-lgEC5o） was thus obtained, in which three parameters were contained, i.e., n-octanol/water partition coefficients （lgKow）, dipole moment of the molecules（ μ） and entropy （S°）. For this equation, R^2 = 0.9582, q^2 = 0.8921 and SD = 0.102. The absolute t-scores of three variables are larger than the standard one in the confidence range of 95%, which confirms the creditability and stability of this model.

关键词： substituted biphenyl linear solvation energy theory,DFT method Daphnia magna toxicity

Synthesis of Calix[4]resorcinarene Core Dendrimers with Peripheral Salicylideneimine Functional Groups

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Chemical Research in Chinese Universities 2006年第4期22卷 537-542页

作者： han Jun GE yun YAN Chao-guo College of Chemistry ＆ Chemical Engineering Yangzhou University Yangzhou 225002 P. R. China

First to third-generation calix[4] resorcinarene core dendrimers, compounds 4a, 4b, 7a, 7b, 10a and 10b, were prepared via the divergent method in seven steps with the corresponding tetraphenyl- and tetra （hydroxyphenyl） calix[4] resorcinarenes （compounds 1a, 1b） as the starting material. The repeat units of the polyamidoamines of these dendrimers were obtained by the ammonolysis of ethyl calixarylacetates 2a and 2b with 1,3-diaminopropane, that is, amide derivatives with terminal amino groups, which in turn reacted with ethyl acrylate to give a higher generation of ester derivatives. The structures of these dendrimers were characterized by IR, ^1H and ^13C NMR spoctrometries. The crystal structure of compound 2b with 12 ethoxycarbonylmethoxy groups was determined by X-ray analysis.

关键词： Calixresorcinarene Dendrimer Schiffbase Amide Calixarene

Nitric Oxide Regulates Dark-Induced Leaf Senescence Through EIN2 in Arabidopsis

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Journal of Integrative Plant Biology 2012年第8期54卷 516-525页

作者： yun-han Niu Fang-Qing Guo The National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research(Shanghai) Institute of Plant Physiology&EcologyShanghai Institutes for Biological Sciencesthe Chinese Academy of SciencesShanghai 200032China

The nitric oxide （NO）-deficient mutant nosllnoal exhibited an early leaf senescence phenotype. ETHY- LENE INSENSITIVE 2 （EIN2） was previously reported to function as a positive regulator of ethylene- induced senescence. The aim of this study was to address the question of how NO interacts with ethylene to regulate leaf senescence by characterizing the double mutant ein2-1 nosllnoal （Arabidopsis thaliana）. Double mutant analysis revealed that the nosllnoal-mediated, dark-induced early senescence phenotype was suppressed by mutations in EIN2, suggesting that EIN2 is involved in nitric oxide signaling in the regulation of leaf senescence. The results showed that chlorophyll degradation in the double mutant leaves was significantly delayed. In addition, nosllnoal-mediated impairment in photochemical efficiency and integrity of thylakoid membranes was reverted by EIN2 mutations. The rapid upregulation of the known senescence marker genes in the nosl/noal mutant was severely inhibited in the double mutant during leaf senescence. Interestingly, the response of dark-grown nosl/noal mutant seedlings to ethylene was similar to that of wild type seedlings. Taken together, our findings suggest that EIN2 is involved in the regulation of early leaf senescence caused by NO deficiency, but NO deficiency caused by NOSIlNOA1 mutations does not affect ethylene signaling.

关键词： Arabidopsis dark EIN2 leaf senescence nitric oxide.

Farmers’Character and Behavior of Fertilizer Application-Evidence from a Survey of Xinxiang County,Henan Province,China

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Agricultural Sciences in China 2009年第10期8卷 1238-1245页

作者： han Hong-yun ZHAO Lian-ge Center for Agricultural and Rural Development Zhejiang University Hangzhou 310029 P.R.China College of Economics Zhejiang Gongshang University Hangzhou 310035 P.R. China

Agricultural chemical use has caused a public concern over environmental issue while decisions about applying chemicals are made by individual farmers. The critical decision-making role of farmers relative to agricultural chemical use creates a need for accurate information on their perceptions of various chemical-related hazards and the factors that may influence such judgments. Based on data collected from 177 land operators at Xinxiang County in Henan Province of China, an empirical analysis is conducted to examine the relationship between farmers＇ character and the behavior of fertilizer application. Study findings reveal that： the characteristics of household head and household, and the nature of farming management positively affect the amount of fertilizers applied; information on fertilizers and the knowledge about environmental impact of fertilizer application have negative impacts by contrast. To formulate effective pollution control policies at the farm level, it is imperative for policy-makers to convey information to producers by demonstration projects, technical assistance, and education programs. Under a changed political environment, some combination of education and economic incentives could be lower cost and more effective tools for achieving desired environmental conservative goals.

关键词： nonpoint-pollution farmers' decision fertilizer application

Construction of flower-like MoS_(2)decorated on Cu doped CoZn-ZIF derived N-doped carbon as superior microwave absorber

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Nano Research 2024年第9期17卷 8250-8260页

作者： yun han Di Lan Mengjun han Zihao Xia Jiaxiao Zou Zirui Jia College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002China

The rational design of composition nanostructures and morphologies of the carbon-based composites materials has a significant potential for tuning electromagnetic parameters and thereby improving their performance as electromagnetic wave(EMW)*** this work,the flower-like Cu/Co-NC/MoS_(2)(NC=N-doped carbon skeleton)composites were successfully prepared by employing CuCoZn-ZIF(ZIF=zeolitic imidazolate framework)as precursor with subsequent annealing and hydrothermal *** unique flower-like morphology and electromagnetic synergy strategy between components enable the as-obtained Cu/Co-NC/MoS_(2)composites to exhibit outstanding microwave absorption ***,the minimum reflection loss of Cu/Co-NC/MoS_(2)reaches-54.36 dB at 2.7 *** the thickness reduces to 2.2 mm,the maximum effective absorption bandwidth can be achieved as large as 6.72 *** research develops useful ideas for optimizing multicomponent microwave absorbing materials.

关键词： ternary metal-organic frameworks(MOFs) MoS_(2) flower-like morphology microwave absorption

Dynamic Installation Behaviors of A New Hybrid Plate Anchor in Layered Marine Clay

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China Ocean Engineering 2021年第5期35卷 736-749页

作者： LAI Ying ZHU Bin CHEN Chuan HUANG yun-han MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China Jiangsu Ocean University Lianyungang 222005China

Layered soil profiles create challenges for foundation installation and detrimentally affect the foundation *** research explored the free-fall penetration behavior of a new dynamically installed plate anchor,the Flying Wing Anchor?,in layered soil *** new concept anchor combines the advantages of low-cost installation of torpedo piles and high efficiency of plate *** is initially installed through free-fall like a torpedo pile,and followed by drag embedment like a plate *** methodology is to perform free-fall penetration tests with a model anchor in a variety of test beds containing marine clays with different profiles of undrained shear strength versus depth.A calibrated prediction model accounting for the effects of strain-rate and stiff layer produces results similar to those from the model *** design curves were developed based on the calibrated analytical model,and are valuable to estimate the impact velocity thresholds of prototype anchor to penetrate through stiff *** free-fall penetration tests indicated that the penetration ability of FWA?increases with the increased impact *** new dynamically embedded plate anchor can penetrate through the stiff layers that would cause problems for the conventional plate anchor,such as the drag embedded anchor,plowing on the top of stiff layer instead of breaking into ***,the new dynamically embedded plate anchor can provide a possible solution for layered soil profiles in deep water.

关键词： layered soils penetration hybrid anchors dynamically installed anchors plate anchors

Free-Fall Penetration Behaviors of A New Dynamically Installed Plate Anchor in Marine Clay

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China Ocean Engineering 2020年第6期34卷 795-805页

作者： LAI Ying HUANG yun-han CHEN Chuan ZHU Bin MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China College of Civil and Harbour Engineering Jiangsu Ocean UniversityLianyungang 222005China

A new dynamically installed plate anchor, the Flying Wing Anchor~?, has been developed as a sustainable anchor concept for deep-water offshore wind turbines. The anchor is firstly installed by free-fall penetration and then followed by drag embedment. If the anchor is subjected to environmental loads, it dives deeper to mobilize a higher capacity. This study presents a series of free-fall penetration tests with model anchors in different weights to assess the anchor behavior during the free-fall penetration performance in one-layer soil with a constant shear strength profile. Anchor velocities and embedment depths were measured by a magnetometer. An energy-based model and a force-based model were calibrated against the test results of model anchors with different weights. Based on the calibrated force-based model, a series of design charts were developed to estimate the embedment depth of anchors in different sizes and with different impact velocities in various marine clays. The framework to plot design charts presented herein can be potentially applied to other dynamically installed anchors to predict embedment depth in engineering practice.

关键词： dynamic anchor dynamic installation plate anchor scale effect design chart

Analysis of retarding effect on α to γ transformation in Fe–C alloy by addition of dispersed particles

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Progress in Natural Science:Materials International 2015年第3期25卷 236-241页

作者： Liang Chen yun han Bin Zhou Jie Gong Key Laboratory for Liquid–Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong University Research Institute of Technology Shougang Corporation Schools of Electrical Computer and Energy EngineeringArizona State University

The effects of dispersed second phase particles on α-ferrite(α) to austenite(γ) transformation at 1140 K in Fe–C alloy were studied by means of phase field simulation. According to the simulated results, it was found that the particle could retard the migration of α/γ interface. Importantly,both the morphology of particles and the interfacial energy of particle/matrix(α or γ) interface affect the magnitude of the retarding effect. More specifically, the particles with smaller aspect ratio bring stronger retarding force, and when the interfacial energy of particle/γ interface is larger than that of particle/α interface, the retarding effect also becomes significant. These phenomena could be explained from the viewpoint of change in the total amount of the interfacial energy of the simulation system.

关键词： α/γ Interface Retarding effect Particle morphology Interfacial energy

TiB2 coating formed on nickel substrates by electroplating in molten salt of fluoride

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中国有色金属学会会刊：英文版 2004年第z1期14卷 132-135页

作者： LONG Jin-ming GUO Zhong-cheng han Xia-yun Faculty of Materials and Metallurgical Engineering Kunrning University of Science and Technology Kunming 650093 China Faculty of Materials and Metallurgical Engineering Kunrning University of Science and Technology Kunming 650093 China Faculty of Materials and Metallurgical Engineering Kunrning University of Science and Technology Kunming 650093 China

The TiB2 coatings deposited over nickel substrate by electroplating was investigated, which is in molten salt of a fluoride mixture involving KF, NaF, K2 TiF6 and KBF4. Effects of temperature, cathodic current density (Jc) and duration on the coating's formation were examined. The composition, morphology and structure of the coatings were characterized by scanning electron microscopy (SEM), energy dispersive X-ray detector (EDS) and X-ray diffraction (XRD). The results show that the coatings, with black, smooth and uniform appearance, are composed of predominating TiB2 and small amounts of nickel titanium oxide (Ni0.75 Ti0.125 O). The coatings show a nodular morphology and the grain size is dependent on the Jc and ranges about 1 - 10 μm. There is a linear relationship between the coating's thickness and the time of electrolysis within certain duration range. The reduction of the potassium can take place simultaneously with the electrochemical synthesis of TiB2 as the Jc is in excess of certain level. The hardness of the TiB2 coatings is likely to be deteriorated due to the presence of potassium and Ni0.75Ti0.125 O in the coatings.

关键词： TiB2 coating electroplating molten salt nickel microstructure