检索结果-南通市图书馆

Effect of Cooling Rate on Morphology and Oxygen Permeability of Polypropylene

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 219-223页

作者： Wei Tian Raymond T. Whodhams(Material Science and Engineering School, University of Science and Technology Beijing, Beijing 100083, China)(Department of Chemical Engineering and Applied Chemistry University of toronto, toronto M5S IA4, Canada) Material Science and Engineering School University of Science and Technology Beijing Beijing 100083 China Department of Chemical Engineering and Applied Chemistry University of Toronto Toronto Ont. M5S IA4 Canada

The influence of different cooling rates on the morphology and oxygen permeabilityr of polypropylene containing ferrocene has been investigated. The spherulitic crystalline size and structure, which can affect the oxygen permeability are dependent upon the heating temperature, annealing time and cooling rate. The modulus of the composite was measured b}' dynamic mechanical analysis.

关键词： polypropylene oxygen permeability cooling rate

A Diagnostic Study of Moist Potential Vorticity Generation in an Extratropical Cyclone

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 1998年第2期15卷 19-33页

作者： Zuohao Cao and G.W.K. Moore Department of Physics, University of toronto, toronto, Ontario, Canada, M5S 1A7 Department of Physics University of Toronto Toronto Ontario Canada

Moist potential vorticity (MPV) and its generation may be important in the development of mesoscale structures such as rainbands within cyclones. In an adiabatic and frictionless flow, MPV generation is possible if the flow is three-dimensional and the air is unsaturated. Moist potential vorticity can be generated through the combined effects of gradients in the potential temperature and moisture fields. The diagnosis of MPV generation in an extratropical cyclone was performed with the ECMWF objectively analyzed fields for a system that developed during February 1992. It was found that at various stages during the development of the cyclone, negative MPV was generated: at the north end of the cold front; along the occluded front and the cold front; and in the region of the warm core. This pattern of negative MPV generation is in excellent agreement with the predictions of previous theoretical and numerical studies. After the cyclone ceased to deepen, the region of negative MPV generated in the cyclone was horizontally advected into a saturated area. The area of negative MPV generated both along the occluded front in this case study and in the region of the bent-back warm front in a numerical simulation showed a mesoscale structure with a width of about 200-500 km. It was found that the intrusion of moist or dry air into baroclinic zones was important for MPV generation. In addition, baroclinicity increase (adjacent to the area of condensation) in the regions of high moisture gradients led to significant MPV production.

关键词： Moist potential vorticity (MPV) generation Extratropical cyclones

Social Semantic Knowledge Management in AEC:Where Wiki meets Ontology

在线全文

学校读者我要写书评

暂无评论

Social Semantic Knowledge Management in AEC:Where Wiki meets...

Executionary pathway for apoptosis: lessons from mutant mice

2010 International Conference on Management Science (ICMS 2010)

作者： Jinyue Zhang Department of Civil Engineering University of toronto toronto Canada

Along with the increasing application of Wiki for knowledge management,researchers began to study the approach to embedding semantics in Wiki *** AEC（Architecture,Engineering and Construction） as the application domain,this paper argues the advantages of using ontologies in Wiki sites for semantic navigation among Wiki pages,meaningful knowledge annotation of Wiki contents,and better retrieval of information and knowledge.

关键词： Wiki ontology knowledge management Semantic Web Social Web

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Cell Research 2000年第4期10卷 267-278页

作者： WOO MINNA RAZQALLAH HAKEM TAK W. MAK Amgen Institute and Ontario Cancer Institute, Departments of Immunology and Medical Biophysics, University of toronto, Canada 1Amgen Institute and Ontario Cancer Institute Departments of Immunology and Medical Biophysics University of Toronto Canada 1Amgen Institute and Ontario Cancer Institute Departments of Immunology and Medical Biophysics University of Toronto Canada 1Amgen Institute and Ontario Cancer Institute Departments of Immunology and Medical Biophysics University of Toronto Canada

Apoptosis or programmed cell death (PCD) is an evolutionarily conserved cellular process that is essential for normal development and homeostasis of multicellular organisms. Defects in the apoptosis signaling result in many diseases including autoimmune diseases and cancer. The apoptosis signaling pathway was first described genetically in the nematode Caenorhabditis elegans which serves as a framework for the more complex apoptotic pathways that exist in mammals. In this review, we will discuss the apoptotic pathways that are emerging in mammals as elucidated by studies of gene-targeted mutant mice.

关键词： Apoptosis progammed cell death caspases death receptors mitochondri?

Studying gene duplication and genetic variation of budding yeast:a systems and interdisciplinary approach

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Studying gene duplication and genetic variation of budding y...

Mechanical Analysis of Concrete Specimen under Restrained Condition

第十一次中国生物物理学术大会暨第九届全国会员代表大会

作者： Zhaolei Zhang University of toronto,Donnelly Centre of Cellular and Biomolecular Research, toronto,Canada

＜正＞Budding yeast（Saccharomyces cerevisiae）is a single cell model organism that is amenable to genome wide experimental interrogation using high-throughput genomics,proteomics and

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2005年第3期20卷 91-94页

作者：马新伟 School of Materials Science and Engineering Harbin Institute of Technology

In order to quantify the development of the tensile stresses and obtain a reliable estimation of the cracking risk, the concrete was subjected to restrained conditions. The fully restrained condition was achieved by keeping the length constant of a concrete specimen. Comparing the free shrinkage with the restrained shrinkage, tensile creep could be discriminated from shrinkage. The testing method was introduced in details, and the mechanical behoviors under tensile lond were analyzed. Results show that conerete exhibits a pronounced viscoelasticity. Under restroined condition, the self-induced tensile stress increases with time. The lower the water to cement ratio, the larger the tensile stress at the same age. The tensile creep of hardening concrete is much larger than that of hardened concrete. The relationships among autogenous shrinkage unter free condition, elastic strain and creep under restrained condition are described, and the mathematical model for the calculation of elastic strain and creep is propased.

关键词： free shrinkage restrained shrinkage tensile creep viscoelasticity

Human hematopoietic cells express two forms of thecytokine receptor common γ-chain (γc)

在线全文

学校读者我要写书评

暂无评论

Cell Research 1997年第2期7卷 195-205页

作者： SHI YU FANG MARY HILL ANTON NOVAK ZHIQING CHEN RUO XIANG WANG CHOONGCHIN LIEW GORDON B. MILLS (Oncology Research, The toronto Hospital, 200 ElizabcthSt., toronto, Ontario, Canada MSG 2C4Department of Immunology, Holland Laboratoryof American Red Cr Oncology Research The Toronto Hospital 200 Elizabeth St. Toronto Ontario Canada M5G 2C4

Recent studies have revealed that the γ-chain of theIL-2 receptor is shared by the receptors for IL-4, IL7, IL-9, IL-13, and IL-15, and it is therefore also referred toas the common γ-chain (γc). Mutations of γc result inX-linked severe combined immunodeficiency syndrome inhumans, indicating that rye is essential for normal development and function of the immune system. We demonstratethat human hematopoietic cells express two γc transcriptsdiffering in their carboxyl terminal coding region. Onetranscript is the previously reported sequence (γc-long),whereas the newly identified sequence exhibits a deletion of72 nucleotides close to the 3'-end of the open reading frame(γc-short). This alteration predicts a loss of 24 amino acidsincluding a conserved tyrosine residue which is shared byseveral members of the cytokine receptor family. Thepresence of these two distinct forms of rye transcripts wasdemonstrated by sequencing of reversely transcribed andpolymerase chain reaction (RT-PCR) amplified mRNA, restriction digestion of the RT-PCR products, RNAse protection, and Northern blotting from human cell lines andhuman peripheral blood lymphocytes. Furthermore, thetwo variants were present in peripheral blood lymphocytesfrom both female and male donors, which rules out allelicvariants since rye is a single copy gene located on the Xchromosome. A truncation mutant at a site near the observed changes in γc-short has been reported by othersto alter biochemical events activated by cytokines. Thiscombined with the loss of a potential SH2 "docking" sitein γc-short suggests that γc-long and γc-short may link todifferent signaling pathways and may play an importantrole in determining the cellular response to IL-2, IL-4, IL-7, IL-9, IL-13, IL-15.

关键词： IL-2 receptor γ-chain cytokine receptor common γ-chain IL-2 receptor cytokine receptors RNA splicing

Hamiltonian Cycles in 2-Connected Claw-Free Graphs

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

新疆大学学报(自然科学版)(中英文) 1999年第1期 2-14页

作者： Li Mingchu (Department of Mathematics,University of toronto,toronto,Ontario,Canada M5S 3G3)

１ＩｎｔｒｏｄｕｃｉｔｉｏｎＩｎｔｈｉｓｐａｐｅｒｗｅｄｅａｌｗｉｔｈｆｉｎｉｔｅｓｉｍｐｌｅｇｒａｐｈｓ．ＬｅｔＧｂｅａｇｒａｐｈ．Ｗｅｄｅｎｏｔｅｂｙδ（Ｇ）（ｏｒδ）ａｎｄｋ（Ｇ）ｔｈｅｍｉｎｉｍｕｍｄｅｇｒｅ... 详细信息

１ＩｎｔｒｏｄｕｃｉｔｉｏｎＩｎｔｈｉｓｐａｐｅｒｗｅｄｅａｌｗｉｔｈｆｉｎｉｔｅｓｉｍｐｌｅｇｒａｐｈｓ．ＬｅｔＧｂｅａｇｒａｐｈ．Ｗｅｄｅｎｏｔｅｂｙδ（Ｇ）（ｏｒδ）ａｎｄｋ（Ｇ）ｔｈｅｍｉｎｉｍｕｍｄｅｇｒｅｅａｎｄｔｈｅｃｏｎｎｅｃｔｉｖｉ...

关键词： Claw-Free Connected Cycles Graphs

Studying gene duplication and genetic variation of budding yeast:a systems and interdisciplinary approach

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

生物物理学报 2009年第S1期25卷 9-9页

作者： Zhaolei Zhang University of toronto, Donnelly Centre of Cellular and Biomolecular Research, toronto, Canada

Budding yeast (Saccharomyces cerevisiae) is a single cell model organism that is amenable to genome wide experimental interrogation using high-throughput genomics, proteomics

关键词： Studying gene duplication and genetic variation of budding yeast gene