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Flame-retardant Mechanism of Magnesium Oxychloride in Epoxy Resin

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Journal of Wuhan university of technology(Materials science) 2009年第1期24卷 127-131页

作者：秦麟卿 State Key Laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of Technology Center for Material Research and Analysis Wuhan University of Technology

Flame-retardant mechanism of magnesium oxychloride （M OC） in EP was in-vestigated by limiting oxygen index （LOI）, XRD, SEM, TG-DTG and DSC. The results show that MOC performed well as an inorganic flame-retardant in EP. When the content of MOC is 50%, the LOI of EP reaches 29.6% and mass of residual char reaches 9.6%. The flame retarde mechanism of MOC is due to the synergies of diluting, cooling, catalyzing char forming and obstructing effects.

关键词： magnesium oxychloride epoxy resin flame-retardant properties flame retardedmechanism

Comparison study of trapped water in human erythrocytes by EPC and DSC method and its application

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science China(Technological sciences) 2004年第3期47卷 343-351页

作者： ZHAO Gang1, HE Liqun1, GUO Xiaojie2, LIU Zhong3. LUO Dawei1,3.& GAO Dayong1,3.1. Cryobiomedical Engineering Research institute, Department of Thermal science and Energy Engineering, university of science and technology of China, Hefei 23.027, China 2. Red Cross Blood Center of Hefei, Hefei 23.022, China 3. Department of Mechanical Engineering, university of Kentucky, Lexington, KY 40506-0108, USA Univ Sci & Technol China Cryobiomed Engn Res Inst Dept Thermal Sci & Energy Engn Hefei 230027 Peoples R China Red Cross Blood Ctr Hefei Hefei 230022 Peoples R China Univ Kentucky Dept Mech Engn Lexington KY 40506 USA

The novel differential scanning calorimetry method for determining trapped water volume of human red blood cell during freezing process has been reexamined. Results show that the final erythrocyte volume is 53. of its isotonic volume after freezing to -40℃. An electronic particle counter (MultisizerTM III, Beckman Coulter Inc., USA) was used to measure cell volume changes in response to hypertonic solution. Using this approach, when extracellular solution was 3.86 mOsm, the equilibrium cell volume was found to be 57% of its isotonic value. Both results indicate that 3.%—40% of intracellular water is trapped and cannot respond to osmotic difference between intra- and extracellular solution. These findings are consistent with the published data: at least 20%—3.% of the isotonic cell water volume is retained within RBCs during freezing. Some applications of the values of trapped water are addressed.

关键词： differential scanning calorimeter/DSC, electronic particle counter/EPC, cell volumetric change, red blood cell/RBC/erythrocyte

Determination of the Thermal Expansion Coefficient of Concrete at Early Ages by Using Temperature-stress Testing Machine

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Journal of Wuhan university of technology(Materials science) 2006年第4期21卷 146-149页

作者：霍凯成 Hubei Key Laboratory of Roadway Bridge & Structure Engineering Wuhan University of TechnologyWuhan 430070China

By using the uptodate temperatuer-stress testing machine, the thermal expansion coefficient of concrete at early ages was studied and indicative conclusions were achieved ： temperature rising due to hydration heat is not directly correlated with cracking, but the temperature and stress evolation process should be taken into consideration in the same time. Proper chemical admixtures and mineral cornpasitions can improve the mechanical properties of concrete such as thermal expansion coefficient, which is very indicative in practice.

关键词： concrete coefficient of thermal expansion temperature-stress test

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.

Congruences on ideal nil-extension of completely regular semigroups

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Chinese science Bulletin 1998年第5期43卷 379-381页

作者： REN Xueming 1, 2 GUO Yuqi 2 and CEN Jiaping (Shum Kar-ping) 3.. Department of Mathematics, Xi’an university of Architecture & technology, Xi’an 710055, China 2. Department of Mathematics, Yunnan university, Kunming 650091, China 3. Department of Department of Mathematics Xi’an University of Architecture & Technology Xi’an China Department of Mathematics Yunnan University Kunming China Department of Mathematics Chinese University of Hong Kong Hong Kong

Let S be an ideal nil-extension of a completely regular semigroup K by a nil semigroup Q with zero. A concept of admissible congruence pairs (δ,ω) of S is introduced, where δ and ω are a congruence on Q and a congruence on K respectively. It is proved that every congruence on S can be uniquely respresented by an admissible congruence pair (δ,ω) of S. Suppose that ρ K denotes the Rees congruence induced by the ideal K of S. Then it is shown that for any congruence σ on S,a mapping Γ:σ|→(σ Q,σ K) is an order-preserving bijection from the set of all congruences on S onto the set of all admissible congruence pairs of S,where σ K is the restriction of σ to K and σ Q=(σ∨ρ K)/ρ K. Moreover,the lattice of congruences of S is also discussed. As a special case,every congruence on completely Archimedean semigroups S is described by an admissible quarterple of S. The following question is asked: Is the lattice of congruences of the completely Archimedean semigroup a semimodular lattice?

关键词： completely regular semigroups ideal nil-extension congruences.

Mining and Integrating Reliable Decision Rules for Imbalanced Cancer Gene Expression Data Sets

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Tsinghua science and technology 2012年第6期17卷 666-673页

作者： Hualong Yu 1 , Jun Ni 2 , Yuanyuan Dan 3., Sen Xu 4 1. School of Computer science and Engineering, Jiangsu university of science and {3., Zhenjiang 212003. China 2. Department of Radiology, Carver College of Medicine, The university of Iowa, Iowa City, IA 52242, USA 3. School of Biology and Chemical Engineering, Jiangsu university of science and {3., Zhenjiang 212003. China 4. School of Information Engineering, Yancheng institute of {3., Yancheng 224051, China School of Computer science and Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China|c|

There have been many skewed cancer gene expression datasets in the post-genomic era. Extraction of differential expression genes or construction of decision rules using these skewed datasets by traditional algorithms will seriously underestimate the performance of the minority class, leading to inaccurate diagnosis in clinical trails. This paper presents a skewed gene selection algorithm that introduces a weighted metric into the gene selection procedure. The extracted genes are paired as decision rules to distinguish both classes, with these decision rules then integrated into an ensemble learning framework by majority voting to recognize test examples; thus avoiding tedious data normalization and classifier construction. The mining and integrating of a few reliable decision rules gave higher or at least comparable classification performance than many traditional class imbalance learning algorithms on four benchmark imbalanced cancer gene expression datasets.

关键词： cancer gene expression data class imbalance paired differential expression genes decision ruleensemble learning majority voting

Holocene grassland vegetation, climate and human impact in central eastern Inner Mongolia

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science China Earth sciences 2005年第7期48卷 1025-1039页

作者： HUANG Fei1, Kealhofer Lisa2, XIONG Shangfa3.& HUANG Fengbao1 1. nanjing institute of Geology and Paleontology,Chinese Academy of sciences,nanjing 210008,China 2. Anthropology and Sociology Department,Santa Clara university,CA 95053.USA 3. institute of Geology and Geophysics,Chinese Academy of sciences,Beijing 100029,China nanjing institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Anthropology and Sociology Department Santa Clara University CA 95053 United States institute of Geology and Geoohysics Chinese Academy of Sciences Beijina 100029 China

Phytolith and pollen preserved in the Taipusi Banner paleosol profile, central eastern Inner Mongolia, provide evidence of Holocene grassland vegetation, climate and human impact. The combined phytolith and pollen records reveal a major change in vegetation composition about 5000 a BP. Before 5000 a BP, the vegetation was dominated by Aneurolepidium Chinese-Stipa grandis grassland of C4 grasses. After 5000 a BP, C4 grasses rapidly retreated, indicating a shift to colder and more arid conditions. The gradual invasion of Stipa krylovii, Ag-ropyron desertorum, Ephedra, Chenopodiaceae and Caragana reveal the onset of grassland degeneration. Between 10000 and 8720 a BP, the Aneurolepidium Chinese-Stipa grandis grassland included a small proportion of Artemisia shrub and Echionopos type plants, implying a strong winter monsoon and very weak summer monsoon. From 8720 to 7000 a BP, C4 grasses were common, indicating a strengthening of the summer monsoon. Between 7000 and 5000 a BP, the Holocene thermal maximum was evident, with a significant expansion of C4 grasses and the presence of some trees (such as Pinus and Betula, and so on) in or near the study site. From 4200?000 a BP, a sandy grassland of Artemisia and Agropyron desertorum together with Aster-type taxa occurred. Precipitation amelioration took place between 3.00 and 2170 a BP, with a rapid development of Echinops type plants and a small expansion of C4 grasses. From 2170 a BP to present, human activities accelerated the process of grassland degeneration.

关键词： phytolith and pollen records grassland environment change human impact Holocene central eastern Inner Mongolia.

Analysis on cohesive crack opening displacement considering the strain softening effect

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science China(Physics,Mechanics & Astronomy) 2006年第1期49卷 88-101页

作者： WANG Limin1, XU Shilang2 & ZHAO Xiqiang3.1. Mechanics Department, Shandong university of technology, Zibo 255049, China 2. Civil Engineering Department, Dalian university of technology, Dalian 116024, China 3. Mathematics Department, Ocean university of China, Qingdao 266071, China Mechanics Department Shandong University of Technology Zibo 255049 China Civil Engineering Department Dalian University of Technology Dalian 116024 China Mathematics Department Ocean University of China Qingdao 266071 China

In order to investigate the crack propagation in quasi-brittle materials like rock, ceramic and concrete, Hillerborg and his co-researchers abstracted the fracture process zone in front of a stress free crack in terms of a “fictitious crack zone”. On the fictitious crack zone, cohesive stresses distribute following a given softening relationship of stress vs. crack opening. Based on the polynomial or power series expression of cohesive crack opening displacement, the relationship of the cohesive stress vs. the crack opening displacement is established using elastic theory and integral equation, and some unknown physics variables are obtained using variation approach. The calculation results gained in this paper are close to the experimentally test ones.

关键词： cohesive crack, softening, dissipation work, variation approach.

SENSITIVE NUMERICAL SIMULATION AND ANALYSIS OF RAINSTORM USING NESTED WRF MODEL

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Journal of Hydrodynamics 2006年第5期18卷 578-586页

作者： WANG Shu-chang HUANG Si-xun LI Yi institute of meteorology PLA University of Science and Technology Nanjing 211101 China

Nowadays, the nested grid model is widely used to increase the resolution of numerical model. An attempt to investigate the influence of the newly developed nesting technique of WRF model on the mesoscale numerical simulation of severe storm is described in this article. The results of sensitivity tests infer that the WRF model give more accurate and vivid prediction of severe storm with nesting scheme. As is shown in the tests, simulating value of the precipitation centers using nesting scheme are larger than those without using nesting scheme, which indicates that the simulating precipitation of nested storm is closer to the real rainfall. And there is obvious improvement of distribution of rain area and position of precipitation centers. According to the high resolution output data of the WRF model, deep and detailed analysis of characters of the mesoscale system that triggers the rainstorm is reported in this article, and the thermal and dynamical characters of this Meiyu front severe storm are also discussed.

关键词： WRF nesting numerical simulation mesoscale analysis