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Structure and property of AgLaY Alloy

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rare Metals 2001年第3期20卷 192-196页

作者： Jinxia Li, Yongtao Liu, Zhenzhong Tai 1) The State Key Lab of rolling and Automation, Northastern university, shenyang 110004, china 2) Maerial & Metallurgical college, Northeastern university, shenyang 110004, china 3) shenyang ASTrON Mining Ltd. Corp., 东北大学轧制技术与连轧自动化国家重点实验室辽宁沈阳 110004 东北大学辽宁沈阳 110004 shenyang ASTrON Mining Ltd 辽宁沈阳 110003

The structure of rE-Ag alloy was observed and analyzed using electron probe. The property changes of the alloy containing two rare earth elements AgLaY during cold forming and the high temperature softening-resistance during annealing were studied using Vickers hardness tester. The distribution and action of the rare earth elements in Ag-alloy were also analyzed. Experimental results show that AgLaY alloy has more remarkable work-hardening effect than AgLa and pure silver, and it also has better thermal-resistance. The effects of rE elements, La and Y, on the properties of Ag-alloy are attributable to their symbiotic distribution and complementary function. Because of the common properties of La and Y as rE elements, they have the completely similar distribution in Ag-alloy. At the same time, La and Y make full use of complementary role in the alloy since they belong to different periods in periodic table and have differences in atomic structure and properties.

关键词： rare earth element rE-Ag alloy heat-resistance structure and property complementarity

pure spin polarized transport based on rashba spin orbit interaction through the Aharonov Bohm interferometer embodied four-quantum-dot ring

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Chinese physics B 2013年第4期22卷 420-428页

作者：吴丽君韩宇 School of Science Shenyang Ligong University Department of physics Liaoning University

The spin-polarized linear conductance spectrum and current–voltage characteristics in a four-quantum-dot ring embodied into Aharonov–Bohm （AB） interferometer are investigated theoretically by considering a local rashba spin–orbit interaction. It shows that the spin-polarized linear conductance and the corresponding spin polarization are each a function of magnetic flux phase at zero bias voltage with a period of 2π, and that Hubbard U cannot influence the electron transport properties in this case. When adjusting appropriately the structural parameter of inter-dot coupling and dot-lead coupling strength, the electronic spin polarization can reach a maximum value. Furthermore, by adjusting the bias voltages applied to the leads, the spin-up and spin-down currents move in opposite directions and pure spin current exists in the configuration space in appropriate situations. Based on the numerical results, such a model can be applied to the design of a spin filter device.

关键词： quantum dot ring rashba spin–orbit interaction spin-polarized transport "bound states in the continuum" phenomena bias voltage Aharonov–Bohm interferometer

Ultrastructural Alteration of Maize plants Infected with the Maize rough Dwarf Virus

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agricultural sciences in china 2002年第5期1卷 531-534页

作者： LI Zhao-hui, GUO Xing-qi, YE Bao-hua and GUO Yan-kui( college of plant protection , Shandong agricultural university, Taian 271018 , p.r.china college of Life sciences , Shandong agricultural university , Taian 271018 , p.r.china) college of plant protection Shandong Agricultural University Taian 271018 P.R. China college of Life sciences Shandong Agricultural University Taian 271018 P. R. China

The ultrastructural alteration of maize plants infected with the maize rough dwarf virus (MrDV) was studied with transmission electron microscopy. The results revealed that aggregates of virus particles , with a diameter of 60nm, were found in the root cell, and always distributed near the vacuole membrane. However, no such particles were checked in leaf cells. Moreover, no virus was observed in choroplasts, mitochondria nuclei, plasmodesmata or intercellular canal of all kinds of infected cells of maize, either. Structures of various organelles changed in the infected leaf and root cells of maize. An inward collapse and localized splitting of the tonoplast were observed, the chloropoast structure was destroyed by MrDV, and the number of destroyed or dysplasia chloroplast in leaf cells with serious symptoms was more than that in leaves without symptoms. The matrix of mitochondria in cells infected by MrDV decreased and some of them expanded and destructed. Nuclei was abnormal and the nuclear membrane was broken. In addition, the infected cells were characterized by a voluminous cytoplasm containing hypertrophied endoplasmic reticulum, with rich ribosome content and lots of starch grain.

关键词： Maize rough dwarf virus Cy topathology Electron microscopy

The pig Lhx8 Gene:cDNA Cloning,Bioinformatic Analysis and Expression Level in Tissues and preimplantation Embryos

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agricultural sciences in china 2009年第12期8卷 1503-1510页

作者： FANG Wei,LI Gui-qiang,LI Mei-li,WANG Wei and XU Yin-xue college of Animal Science & Technology,Nanjing agricultural university,Nanjing 210095,p.r.china college of Animal Science & Technology Nanjing Agricultural University Nanjing 210095 P.R. China

Evidence has shown in mouse that Lhx8 is a critical factor for maintenance and differentiation of the oocyte during early oogenesis. In the current paper, attempts were made to clone and characterize a gene encoding Lhx8 from pig. rapid amplification of cDNA ends （rACE） gave rise to a full-length of Lhx8 which contained 1 681 bp nucleotides, with a complete open reading frame of 885 bp, encoding a 295 amino acid polypeptide. Homology search and sequence multialignment demonstrated that the deduced pig Lhx8 protein sequence shared a high identity with Lhx8 from other mammals, including several highly conservative motifs and amino acids. The phylogenetic tree of the LIM superfamily proteins has been constructed to reveal the evolutionary relationship of various species. rT-pCr analysis showed that the Lhx8 gene was expressed in gonad and immunity tissues. In preimplantation embryos, Lhx8 mrNA expression profiling using realtime pCr revealed that its mrNA levels were highest in 4-cell stage embryos and gradually decreased until the blastocyst stage.

关键词： pig LhxS molecular cloning mrNA expression qrT-pCr preimplantation embryos

partial Inverse Grain Size Dependence of Strength in High Mn Steels Microalloyed With Nb

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Journal of Iron and Steel research International 2012年第9期19卷 68-72页

作者： DING Hua 1 , 2 , LI Hua-ying 1 , DING Hao 1 , QIU Chun-lin 2 , TANG Zheng-you 1 ( 1.School of Materials and Metallurgy , Northeastern university , shenyang 110819 , liaoning , china 2.State Key Lab of rolling and Automation , Northeastern university , shenyang 110819 , liaoning , china ) School of Materials and Metallurgy Northeastern University Shenyang Liaoning China State Key Lab of rolling and Automation Northeastern University Shenyang Liaoning China

Two steels without and with Nb addition were chosen to investigate the effects of Nb on the microstructures and the mechanical properties of Fe-Mn-Al-Si *** results revealed that Nb refined the grains markedly and both TrIp and TWIp effects occurred during deformation *** Nb containing steel possesses higher yield strength and much lower tensile strength , the latter being explained by the suppression of TrIp effect due to the increase of stacking fault *** indicates grain refining is secondary for strengthening of steels when TrIp or TWIp effect exists during the deformation of low carbon and high Mn steels.

关键词： grain size strength high Mn steel Nb

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.

Characteristics of rice plant with Heavy panicle

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Journal of Integrative Agriculture 2006年第12期5卷 911-918页

作者： MA Jun1, 2, MA Wen-bo3, MING Dong-feng4, YANG Shi-ming1, 2 and ZHU Qing-sen5 1 rice research Institute, Sichuan agricultural university, Wenjiang 611130, p.r.china 2 Key Laboratory of Southwest Crop Genetic resources and Improvement, Ministry of Education/Sichuan agricultural university, Yaan 625014, p.r.china 3 Zaozhuang Agriculture Bureau, Shandong province, Zaozhuang 277160, p.r.china 4 Zaozhuang Teacher college, Zaozhuang 277160, p.r.china 5 college of Agronomy, Yangzhou university, Yangzhou 225009, p.r.china rice research Institute Sichuan Agricultural University Wenjiang 611130 P.R.China Key Laboratory of Southwest Crop Genetic resources and Improvement Ministry of Education/Sichuan Agricultural University Yaan 625014 P.R.China Zaozhuang Agriculture Bureau Shandong Province Zaozhuang 277160 P.R.China Zaozhuang Teacher college Zaozhuang 277160 P.R.China college of Agronomy Yangzhou University Yangzhou 225009 P.R.China

Using 15 indica rice varieties with different panicle weight, some ideal plant type characteristics in heavy panicle type of hybrid rice (HpT) and their relation to yield and its components were studied. results showed that the leaf area index (LAI) of the HpT varieties was lower than that of medium panicle type (MpT) and light panicle type (LpT) varieties, but its decreasing rate of LAI and efficient LAI after heading was slower and had much higher percentage of efficient LAI, specific leaf weight, and ratio of grain to leaf area (cm2) in comparison with the MpT and the LpT varieties. The length, width, thickness, and area of top three leaves of the HpT varieties were significantly larger than those of the MpT and the LpT varieties, and these components of top three leaves were significantly and positively correlated with the number of spikelets and filled grains, grain weight per panicle, and grain yield. The flag leaf in HpT varieties was erect with sorrow leaf angle, and their leaf angle of 2nd and 3rd leaf from top increased in sequence. The plant height of the HpT varieties was higher than that of the MpT and the LpT varieties, and their leaf site of top three leaves also increased in sequence. Therefore, HpT varieties as an ideal plant type could increase the utilization efficiency of sunlight energy. The ideal plant type characteristics and their adjuncts for the HpT varieties are proposed in this article.

关键词： heavy panicle type rice plant type characteristics

Solution of a hollow thick-wall cylinder subject to quadric function pressures and its limit when l→∞

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Science china(Technological sciences) 2004年第2期47卷 229-236页

作者： LIU Zhubai1,SHAN rui2,LIU Wen2 & NI Liyong1 1.college of Mechanical Engineering,Yanshan university,Qinhuangdao 066004,china 2.college of Science,Yanshan university,Qinhuangdao 066004,china college of Mechanical Engineering Yanshan University Qinhuangdao China college of Science Yanshan University Qinhuangdao China

The problem of a hollow thick-wall cylinder subject to quadric function pressures is solved with a new stress function, thus laying the basis for solving the spatial symmetric deformation of a hollow cylinder subject ... 详细信息

关键词： quadric function pressure, analytic solution, stress function, hollow cylinder.

Some properties of Cauchy-Type Singular Integrals in Clifford Analysis

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Journal of Mathematical research with Applications 2012年第2期32卷 189-200页

作者： Heju YANG 1,2,Yuying QIAO 1,Sha HUANG 1 1.college of Mathematics and Information Science,Hebei Normal university,Hebei 050016,p.r.china 2.college of Science,Hebei university of Science and Technology,Hebei 050018,p.r.china college of Mathematics and Information Science Hebei Normal University Hebei 050016

First,we give a module estimation of the singular integral with a differential *** by proving the existences of Cauchy principal value we obtain the transformation formula of the Cauchy-type singular integrals with a ... 详细信息

关键词： Clifford analysis Cauchy principal value Cauchy-type singular integral with a parameter transformation formula.