探讨钢筋混凝土框架施工工艺

文章分析了钢筋混凝土框架结构施工中的工艺流程、质量控制工作，对工艺中存在的质量问题提出了相应的控制措施，以供工程技术人员参考。     

Enhanced mechanical properties of AZ31 magnesium alloy sheets by continuous bending process after V-bending

The effects of V-bending process, continuous bending process and combination process on the microstructure and mechanical properties and formability of an AZ31 magnesium alloy sheet were investigated. The experimental results showed that no twins were found in the microstructure of all samples after processes due to the fine grain. The V-bending and continuous bending processes were proved to be an effective approach to modify the mechanical properties and formability. While the samples after the combination process exhibited better mechanical properties and formability than the single processed sample. The yield strength significantly decreased with the value of 100 MPa and the fracture elongation enhanced to 18.3% at room temperature. The Erichsen value was 5.0 mm which was significantly increased by 117% compared with as-received sample. The superior formability of combination processed samples was mainly attributed to the smaller r-value and n-value.     

基尼系数法在乡镇企业发展空间非均衡测度中的应用

针对我国乡镇企业发展空间非均衡问题,选取2003-2012年乡镇企业总产值和乡镇企业营业收入2个指标数据,采用基尼系数法,分析了我国乡镇企业发展空间非均衡的特征、程度及其来源。结果表明:我国乡镇企业空间非均衡程度最大的是西部,其次是东部和中部地区最小。全国整体以及东、西部地区内部乡镇企业发展的空间非均衡程度均呈现进一步加深趋势,中部地区乡镇企业发展的空间均衡程度得到小幅缓解。区域间差距与剩余项差距反向变动是引致我国乡镇企业发展空间非均衡程度发生变动的重要因素。     

A second generation human haplotype map of over 3.1 million SNPs

We describe the Phase II HapMap, which characterizes over 3.1 million human single nucleotide polymorphisms (SNPs) genotyped in 270 individuals from four geographically diverse populations and includes 25-35% of common SNP variation in the populations surveyed. The map is estimated to capture untyped common variation with an average maximum r2 of between 0.9 and 0.96 depending on population. We demonstrate that the current generation of commercial genome-wide genotyping products captures common Phase II SNPs with an average maximum r2 of up to 0.8 in African and up to 0.95 in non-African populations, and that potential gains in power in association studies can be obtained through imputation. These data also reveal novel aspects of the structure of linkage disequilibrium. We show that 10-30% of pairs of individuals within a population share at least one region of extended genetic identity arising from recent ancestry and that up to 1% of all common variants are untaggable, primarily because they lie within recombination hotspots. We show that recombination rates vary systematically around genes and between genes of different function. Finally, we demonstrate increased differentiation at non-synonymous, compared to synonymous, SNPs, resulting from systematic differences in the strength or efficacy of natural selection between populations.     

Genome-wide detection and characterization of positive selection in human populations

With the advent of dense maps of human genetic variation, it is now possible to detect positive natural selection across the human genome. Here we report an analysis of over 3 million polymorphisms from the International HapMap Project Phase 2 (HapMap2). We used 'long-range haplotype' methods, which were developed to identify alleles segregating in a population that have undergone recent selection, and we also developed new methods that are based on cross-population comparisons to discover alleles that have swept to near-fixation within a population. The analysis reveals more than 300 strong candidate regions. Focusing on the strongest 22 regions, we develop a heuristic for scrutinizing these regions to identify candidate targets of selection. In a complementary analysis, we identify 26 non-synonymous, coding, single nucleotide polymorphisms showing regional evidence of positive selection. Examination of these candidates highlights three cases in which two genes in a common biological process have apparently undergone positive selection in the same population:LARGE and DMD, both related to infection by the Lassa virus, in West Africa;SLC24A5 and SLC45A2, both involved in skin pigmentation, in Europe; and EDAR and EDA2R, both involved in development of hair follicles, in Asia.     

微束X射线荧光分析谱仪及其对松针中元素的分布分析

介绍了一种小型的微束X射线荧光分析谱仪,它是由导管X光透镜和能量色散X射线荧光分析谱仪组成.谱仪具有较高的空间分辨率和能量分辨率.使用本谱仪对松树针叶进行了微区分析,得出各种元素沿松针长度方向和横切面径向的分布规律.结果表明使用X光透镜的微束X射线荧光分析方法可以实现植物样品的微区分析,有助于进一步了解植物的生长与元素迁移的关系.     

论食品安全学的理论基础与技术体系

食品安全学（foodsafetiology）是研究食物对人体健康危害的风险和保障食物无危害风险的学问,是食 品科学的一个分支,也是近３０年来发展起来的一门新兴学科。讨论、交流和理解食品安全学的理论基础与技术 体系将有助于促进食品安全学的科学研究、学科建设和人才培养,有助于加强国家食品安全管理和监管能力建 设。在研究大量有关国际组织文件、学术报告、会议文集,以及作者亲自考察、学术研究、自身理解的基础上, 提出了食品安全学的概念,归纳了食品安全学的理论基础和技术体系,探讨了食品安全学的学科构架。     

大型板装配拼接节点试验研究

提出了装配整体式钢筋混凝土大型板一种新的横向拼接节点构造,对9根新型横向连接预制板试件进行试验研究与承载力分析,量测并分析试件的荷载、挠度及应变,观测试件的裂缝发展情况和破坏过程.试件的破坏形态包括弯曲破坏、受剪破坏及轴向拉伸破坏等形式.试验表明,该新型横向连接节点连接可靠,具有良好的承载能力和延性.对新型横向连接节点...     

不旋转钢丝绳直线受拉下的物理建模及力学分析

基于微分几何学、弹性力学相关理论,建立了不旋转钢丝绳直线状态受拉力作用下的物理模型,推导了该状态下的受力方程;根据空间螺旋线方程,在三维CAD软件ProE中建立了不旋转钢丝绳的实体模型,并把该实体模型导入ANSYS中进行力学分析,对该模型的正确性进行验证.模型计算结果与有限元分析结果基本一致,验证了该模型的正确性.