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Journal of Wuhan university of Technology(Materials science) 2006年第4期21卷 78-82页

作者：冯永宝 college of Materials science and Engineering Nanjing University of Technology Nanjing 210009 China

The effects of types and amounts of silane coupling agent on mechanical properties of vuleanized rubber microwave absorbing patch （VRMAP） were studied. The mechanisms of silane coupling agent＇s effects on mechanical properties of rubber microwave absorbing patch （ RMAP ） and microvave absorbing patch＇s （MAP＇s） mierostrueture were also discussed by using SEM and FT-IR. The experimental results show that the tensile strength of RMAP could be increased through adding the filler of carbonyl iron powder （CIP） modified by silane coupling agent. RMAP fiUed with CIP, which was treated by silane coupling agent KH550, possessed a high tensile strength of 11.5 MPa, which was 448% more than that of MAP whose filler wus not modified by any coupling agent. It was found that the optimal amount of KH550 was 1.0 phr to 100.0 phr carbonyl iron powder. The effects of different modifying techniques on RMAP＇s mechanical properties were also inrestigated. It is indieated that MAP whose filler is modified by the wet process has the highest tensile strength, but it is not the optimal modiifying technique due to complieated wet process. On the contrary, the dry process was very simple, and VRMAP possessed fairly high mechanical properties, therefore, it was the perfect modifying process.

关键词： silane coupling ageat carbonyl iron powder microwave absorbing patch mechanical property mierostructure

Studies on the Host Biotypes and Its Cause of Cotton Aphidin nanjing,china

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agricultural sciences in china 2002年第11期1卷 1211-1215页

作者： LIU Xiang-dong, ZHAI Bao-ping and zhang Xiao-xi(college of Plant Protection, nanjing agricultural university, nanjing 210095, P. R. china) college of Plant Protection Nanjing Agricultural University Nanjing 210095P.R.China

The fitness of cotton aphid, Aphis gossypii Glover, on different host plants was studied. The results showed that the cotton aphid population in nanjing formed host preference bio-types on cucumber and cotton. The aphids from cotton and cucumber could not inter-transplant successfully between the two host plants. The apterous and alate offspring of stem mother from hibiscus could not survive, reproduce and form population normally when they were transplanted to cucumber and water melon, but they could form normally when transplanted to cotton and muskmelon. There was no significant difference between the stylet length of cotton aphids from cucumber and cotton, so the stylet length was not the cause of the host preference. When the aphids originated on hibiscus were transplanted to cotton, water melon and muskmelon, the stylet could reach host phloem to absorb host plant’s nutrients, but it couldn’t when transplanted to cucumber. Cotton aphid can feed on muskmelon without secretion of water-soluble saliv

关键词： Aphis gossypii Host transplantation Host biotypes EPG Stylet length

NUMERICAL MODELING PURIFICATION PERFORMANCE OF POT TEST

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Journal of Hydrodynamics 2010年第5期22卷 709-718页

作者： DAI Yu WANG De-guan zhang Jin-feng LUAN Qing-hua Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education Hohai University Nanjing 210098 China college of Mechanics and Materials science Hohai University Nanjing 210098 China college of Environmental Hohai University Nanjing 210098 China college of Water Conservancy and Hydropower Hebei University of Engineering Handan 056021 China

A three-dimensional mathematical model was developed to simulate the pollutant removal efficiency of the soil and plants in the pot test. The advection, dispersion, diffusion, adsorption, biochemical reaction and plant uptake processes were taken into account in the model. The three-dimensional modified Richards equation was used in simulating flow field. The mass balance law was employed in deriving the equation for pollutant transport, where the diffusion and dispersion were described with the Fick-type law, the adsorption was macroscopically expressed as form isotherm, and the bio-chemical degradation process was assumed to follow the Monod kinetics. The mathematical model was descretized by the finite element numerical method. In the pot test, the hydraulic loading was assumed to have the intermittent pattern simulating the rainfall duration and the occurrence of frequency, and the concentrations of pollutants in the influent and effluent were measured. The computed overall removal rates for the CODCr and TN in four cases are in the range of 90.62% - 95.43% and 85.01% - 96.46%, respectively. The differences between the computed and tested overall removal rates for the CODCr and TN are smaller than 5%. The time-varying oscillation pattern of the concentrations of the CODCr and TN were rationally simulated, which showed that the model presented in this article could be used to assess the pollutant removal efficiency of the soil and plants in related cases.

关键词： pot test numerical modelling pollutant removal efficiency experiments

Analysis of IGF2 mRNA expression and its methylation status between cattle yaks and their parents

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Progress in Natural science:Materials International 2009年第9期19卷 1063-1069页

作者： Zhenshan Liu a,b,1, Qifa Li a,1, Qingbo zhang a, Xuguang Qu a, Liyan Dong a, Chamba Yang-zom c, Zhuang Xie a,*, Honglin Liu a a Laboratory of Animal Reproductive Genetics and Molecular Evolution, college of Animal science and Technology, nanjing agricultural university, nanjing 210095, china b Institute of Animal Husbandry and Veterinary Medicine, Shandong Academy of agricultural sciences, Jinan 250100, china c college of Agriculture and Animal Husbandry, Tibet university, Linzhi 860000, china [a]Laboratory of Animal Reproductive Genetics and Molecular Evolution College of Animal Science and Technology Nanjing Agricultural University Nanjing 210095 China [b]Institute of Animal Husbandry and Veterinary Medicine Shandong Academy of Agricultural Sciences Jinan 250100 China [c]College of Agriculture and Animal Husbandry Tibet University Linzhi 860000 China

Cattle yaks are an F1 hybrid between cattle and yaks and exhibit significant hybrid vigor. However, cattle yaks are sterile males. To study the epigenetic aspects of this reproductive isolation, IGF2 mRNA expression in cattle yaks and their parents and the patterns of the IGF2 differentially methylated regions (DMR) were examined in blood and testes. The results showed that IGF2 expression in cattle yaks’ testes was lower than in their parents (P 0.05). Our study showed that IGF2 plays an important role in bovine spermato-genesis and might be involved in cattle-yak male sterility. The methylation level of the IGF2 DMR was irrelevant to the lower expression of IGF2 in cattle yaks; other factors perhaps play roles in its expression.

关键词： Cattle yak Male sterility IGF2 gene mRNA expression DNA methylation

Comparison of the fracture process of the rubberized concrete and plain concrete under bending load

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science china(Technological sciences) 2010年第6期53卷 1526-1533页

作者： zhang YaMei1,WANG Chao2,LU Yi1 & MA AiBin2 1 Jiangsu Key Laboratory of Construction Materials,Southeast university,nanjing 211189,china 2 college of Materials science and Engineering,Hohai university,nanjing 210098,china 1. Jiangsu Key Laboratory of Construction Materials Southeast University Nanjing 211189 China2. College of Materials Science and Engineering Hohai University Nanjing 210098 China

Acoustic emission (AE) technique is employed to investigate the damage process of the notched plain concrete and rubberized concrete specimens under 3-point bending *** signals in the fracture process of notched specimens are illustrated by analyzing the distribution of amplitude and hit rate of AE *** signals in the rubberized concrete have lower activity and amplitude than in the plain *** AE location analysis,it is found that the high energy events mainly are distributed near the notch *** to AE energy,the fracture process zone (FPZ) is *** comparing the FPZ of both concretes,it is found that the incorporation of rubber particles in concrete can greatly alleviate the damage process of concrete specimens and the damage zone in the rubberized concrete is much smaller than in the plain *** moment tensor is also used to analyze the type of cracks and it is found that tensile cracks dominate the early period of loading,while shear cracks become dominant with propagation of cracks in late load period.

关键词： concrete rubberized concrete acoustic emission damage moment tensor

ANALYSIS OF WATER QUALITY IN SHALLOW LAKES WITH A TWO-DIMENSIONAL FLOW-SEDIMENT MODEL

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Journal of Hydrodynamics 2007年第4期19卷 501-508页

作者： JI Yong zhang Jie YAO ei ZHAO Di-hua Nanchang Institute of Technology Nanchang 330099 China college of Environmental science and Engineering Hohai University Nanjing 210098 China nanjing Hydraulic Research Institute Nanjing 210098 China

The governing equation for sediment pollutions was derived based on the turbulent diffusion of pollutants in shallow lakes. Coupled with shallow water equations, a depth-averaged 2-D flow and water quality model was developed. By means of the conservation law, a proposed differential equation for the change of sediment pollutants was linked to the 2-D equations. Under the framework of the finite volume method, the Osher approximate Riemann solver was employed to solve the equations. An analytical resolution was used to examine the model capabilities. Simulated results matched the exact solutions especially well. As an example, the simulation of CODMn in the Wuli Lake, a part of the Taihu lake, was conducted, which led to reasonable results. This study provides a new approach and a practical tool for the simulation of flow and water quality in shallow lakes.

关键词： sediment falling velocity turbulence flow and water quality model finite volume method approximate Riemann solver shallow water equation advection-dispersion equation

Deforestation in Latin America in the 2000s predominantly occurred outside of typical mature forests

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The Innovation 2024年第3期5卷 88-98页

作者： Zhiyu zhang Wenjian Ni Shaun Quegan Jingming Chen Peng Gong Luiz Carlos Estraviz Rodriguez Huadong Guo Jiancheng Shi liangyun Liu Zengyuan Li Yating He Qinhuo Liu Yosio Shimabukuro Guoqing Sun Key Laboratory of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijing 100101China university of Chinese Academy of sciences Shijingshan DistrictBeijing 100049China chinal of Mathematics and Statistics University of SheffieldSheffield S37RHUK Department of Geography and Program in Planning University of TorontoTorontoON M5S 3G3Canada Department of Earth sciences and Department of Geography University of Hong KongHong KongChina Forest science Department Luiz de Queiroz College of AgricultureUniversity of São PauloAv.Pádua Dias11Piracicaba 13418-900Brazil National Space science Center Chinese Academy of SciencesBeijing 100190China Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing 100091China Research Institute of Forest Policy and Information Chinese Academy of ForestryBeijing 100091China Remote Sensing Department National Institute for Space Research(INPE)Av.dos Astronautas 1758São Josédos Campos 12227-010Brazil Department of Geographical sciences University of MarylandCollege ParkMD 20742USA

The role of tropical forests in the global carbon budget remains controversial,as carbon emissions from deforestation are highly *** high uncertainty arises from the use of either fixed forest carbon stock density or maps generated from satellite-based optical reflectance with limited sensitivity to biomass to generate accurate estimates of emissions from *** space missions aiming to accurately map the carbon stock density rely on direct measurements of the spatial structures of forests using lidar and *** found that lost forests are special cases,and their spatial structures can be directly measured by combining archived data acquired before and after deforestation by space missions principally aimed at measuring ***,using biomass mapping,we obtained new estimates of carbon loss from deforestation ahead of forthcoming space ***,using a high-resolution map of forest loss and the synergy of radar and lidar to estimate the aboveground biomass density of forests,we found that deforestation in the 2000s in Latin America,one of the severely deforested regions,mainly occurred in forests with a significantly lower carbon stock density than typical mature forests.

关键词： forest Latin lidar

Multi-objective dynamic detection of seeds based on machine vision

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Progress in Natural science:Materials International 2007年第2期17卷 217-221页

作者： XUN Yi, zhang Junxiong, LI Wei and CAI Weiguo ( college of Engineering, china agricultural university, Beijing 100083, china college of science, Dalian Fisheries university, Dalian 116023, china) [a]college of Engineering China Agricultural University Beijing China [b]college of science Dalian Fisheriers University Dalian China

An approach to inspecting massive numbers of moving seeds was studied based on the techniques of dynamic inspection and machine vision. A progressive scanning CCD camera with external trigger function was used for real-time capture of dynamic images of seeds. The methods based on R channel of RGB (Red, Green and Blue) and region-dependent segmentation were adopted to reduce the data size of image processing and improve the efficiency of seeds inspection. All the seeds were sorted into four grades according to their morphological characteristics, such as surface area, perimeter, major axis, minor axis, circularity and eccentricity. The detection experiments indicated that the eligible ratio of the classifications was about 81.90% by this real-time inspection system.

关键词： machine vision seed sorting multi-objective morphological parameter.

Effect of Zn^(2+) Content on the Microstructure and Magnetic Properties of Nanocrystalline Ni_(1-x)Zn_xFe_2O_4 Ferrite by a Spraying-coprecipitation Method

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Journal of Wuhan university of Technology(Materials science) 2010年第3期25卷 429-431页

作者：刘银 college of Materials science and Engineering Anhui University of Science and Technology

Nanocrystalline Ni1-xZnxFe2O4 ferrites with 0≤x≤1 were successfully prepared by a spraying-coprecipitation *** microstructure was investigated by using XRD and *** properties were measured with vibrating sample magnetometer（VSM） at room *** results show that the grain size of nanocrystalline Ni1-xZnxFe2O4 ferrite calcined at 600 ℃ for 1.5 h is about 30 *** parameter and specific saturation magnetization Ms of nanocrystalline Ni1-xZnxFe2O4 ferrite increase with the Zn^2＋ ions content at room temperature,and maximum Ms is 66.8 A·m^2·kg^-1 as the Zn^2＋ ions content is around 0.5,and coercivity Hc of the nanocrystalline Ni1-xZnxFe2O4 ferrite decreases with Zn^2＋ ions content.

关键词： nanocrystalline material Ni-Zn ferrite spraying-coprecipitation method magnetic properties microstructure

Neuroglobin mutation associated with hypoxia adaptation in Tibet chicken

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Progress in Natural science:Materials International 2007年第12期17卷 1419-1424页

作者： zhang Lifan1, Liu Chong2, Lian Linsheng3, Zhao Chunjiang1, Bao Haigang1 and Wu Changxin1(1. college of Animal science and Technology, china agricultural university, Beijing 100094, china 2. college of Biological science, china agricultural university, Beijing 100094, china 3. college of Animal science and Technology, Yunnan agricultural university, Kunming 650201, china) college of Animal science and Technology China Agricultural University Beijing 100094 China college of Biological science China Agricultural University Beijing 100094 China college of Animal science and Technology Yunnan Agricultural University Kunming 650201 China

Globin protein family plays an important role in storing and transporting oxygen. As a newly reported globin, the revealed function of neuroglobin includes binding and storing oxygen as well as facilitating the utilization of oxygen in neuronal cells. In the present study, mutations in exons of chicken Ngb gene were identified with the method of sequencing and created restriction site PCR in Tibet chicken and other four lowland chicken breeds. The mutations of Lys-2224(E4)-Asn and Ser-2279(E4)-Gly were identified in exon 4 of the gene. The Lys-2224(E4)-Asn mutation existed only in Tibet chicken and the mutation frequencies increased with increasing altitude. Analysis of the haplotype and diplotype of the two mutations in Tibet chicken populations of different altitudes showed that the frequencies of TG haplotype and TTGG diplotype also increased with increasing altitude, while the reverse tendency was found on GGAA diplotype. Under the hypoxic simulation incubation, the main haplotype was TG in living embryos and GA in dead embryos. The results showed that the Lys-2224(E4)-Asn mutation may be a specific mutation associated with hypoxia adaptation in Tibet chicken.

关键词： Tibet chicken neuroglobin hypoxia adaptation Ngb gene mutation.