外推法计算高温气体恒压摩尔热容

恒压摩尔热容是化工热力学中计算过程热力学性质变化所需的基础数据,但手册中通常难以查到计算气体在高温范围恒压摩尔热容所需的数据。文中提出一种计算气体在高温范围的恒压摩尔热容的方法:首先从手册数据适用的温度范围的上限起按一定的温度间隔逐点外推,再用五点曲线平滑法处理各点数据,然后将所得各点数据用线性回归方法处理得到恒压摩尔热容与温度的函数关系式: Cp,m=a0+a1T+a2T2+a3T3+a4T4,用以计算气体在高温范围的恒压摩尔热容。对CO气体,将用此方法计算的结果与用统计热力学方法计算的结果进行了比较,二者具有很好的一致性。     

铁电薄膜开关特性测量

对铁电薄膜的开关特性进行了分析．介绍了利用美国ＨＰ４１９２Ａ低频阻抗分析仪设计铁电薄膜开关特性测量仪的方法．讨论了测量原理以及如何利用测量仪所产生的双极性双脉冲对铁电薄膜的开关特性进行测量,给出了有关ＰＺＴ（５５／４５）铁电薄膜样品的测量结果     

聚碳酸酯结构及热稳定性研究

用ＦＴＩＲ及ＮＭＲ研究聚碳酸酯结构表明,不同生产方法生产的ＰＣ在化学结构上存在差异,酯交换法ＰＣ结构规性劣于光气法ＰＣ。ＧＰＣ法测定ＰＣ分子量分布表明,光气法产品分子量分布较酯交换法产品规整。由于链结构规整性差异,使不同生产方法及工艺生产的ＰＣ热稳定性不同。     

连续可调直流高压稳压电源的研制

本文介绍一种从400~1500伏连续可调直流稳压电源的设计与制作,其设计思想可移植到其他高压稳压电源中。     

Disrupted function and axonal distribution of mutant tyrosyl-tRNA synthetase in dominant intermediate Charcot-Marie-Tooth neuropathy

Charcot-Marie-Tooth (CMT) neuropathies are common disorders of the peripheral nervous system caused by demyelination or axonal degeneration, or a combination of both features. We previously assigned the locus for autosomal dominant intermediate CMT neuropathy type C (DI-CMTC) to chromosome 1p34-p35. Here we identify two heterozygous missense mutations (G41R and E196K) and one de novo deletion (153-156delVKQV) in tyrosyl-tRNA synthetase (YARS) in three unrelated families affected with DI-CMTC. Biochemical experiments and genetic complementation in yeast show partial loss of aminoacylation activity of the mutant proteins, and mutations in YARS, or in its yeast ortholog TYS1, reduce yeast growth. YARS localizes to axonal termini in differentiating primary motor neuron and neuroblastoma cultures. This specific distribution is significantly reduced in cells expressing mutant YARS proteins. YARS is the second aminoacyl-tRNA synthetase found to be involved in CMT, thereby linking protein-synthesizing complexes with neurodegeneration.     

基于GA的多层次概念归纳学习方法

面向属性的归纳学习(亦称概念提升)是一种广泛使用的知识发现方法。通过归纳学习,使得属性域取值的抽象程度提高,从而得到较精练的数据集合,大大提高了规则的学习效率。但是实际应用环境中的数据属性维数非常多,属性概念层次也非常复杂,基于集合论的传统学习方法的效率变得越来越低。基于遗传算法的高搜索性能,提出了一个概念空间的特征概念层次优化搜索方法,特别是处理高维、具有复杂概念层次的问题时收到了较好的效果。     

Meta-analysis identifies multiple loci associated with kidney function-related traits in east Asian populations

Chronic kidney disease (CKD), impairment of kidney function, is a serious public health problem, and the assessment of genetic factors influencing kidney function has substantial clinical relevance. Here, we report a meta-analysis of genome-wide association studies for kidney function-related traits, including 71,149 east Asian individuals from 18 studies in 11 population-, hospital- or family-based cohorts, conducted as part of the Asian Genetic Epidemiology Network (AGEN). Our meta-analysis identified 17 loci newly associated with kidney function-related traits, including the concentrations of blood urea nitrogen, uric acid and serum creatinine and estimated glomerular filtration rate based on serum creatinine levels (eGFRcrea) (P < 5.0 × 10(-8)). We further examined these loci with in silico replication in individuals of European ancestry from the KidneyGen, CKDGen and GUGC consortia, including a combined total of ～110,347 individuals. We identify pleiotropic associations among these loci with kidney function-related traits and risk of CKD. These findings provide new insights into the genetics of kidney function.     

胶州湾潮滩整治工程对潮流泥沙影响及冲淤预测分析

潮滩开挖后回淤问题一直困扰航道建设和港口发展的突出问题,为探究胶州湾北部海湾整治工程在不同开挖方案下潮流场分布情况,本研究通过对胶州湾北部海域进行潮流数值模拟,基于二维平面不可压缩雷诺平均纳维埃-斯托克斯（Navier-Stokes）浅水方程,对比分析两种潮滩开挖方案对航道水动力条件及冲淤变形影响。研究结果表明,工程疏浚后,开挖区及附近海域涨潮流作用明显增强,落潮流深槽流速降低,产生进水加速,出水缓慢的效应,方案二涨潮流作用增强而落潮流减小效应大于方案一。工程完成以后,开挖区有所淤积,方案一潮滩开挖区年平均淤强约15.6cm/a, 方案二约为19.0cm/a,淤积强度由深水区向浅水区逐渐增加,工程疏浚产生的涨潮流增强、落潮流减弱的效应将使淤积加速。     

各向异性孔隙地层随钻声波测井理论模拟及应用

储层中普遍存在的各向异性和渗透性均会对弹性波传播产生影响。为满足油气资源勘探需求,对复杂储层中各向异性与渗透率的测量评价已逐渐从常规的电缆测井(wireline, WL)发展为随钻声波测井(acoustic logging while drilling, ALWD)。建立随钻声波测井模型,以Biot理论为基础研究了弹性波在横观各向同性孔隙地层中的传播机制,并对含有钻铤的充液井孔内各部分声场进行分析,导出了横观各向同性孔隙地层随钻声波测井的声场表达式。研究了随钻多极子声场模式波的频散特征。结合时间-慢度相关法分析了阵列波形中地层波和钻铤波的到时及慢度特征。结果表明：随钻斯通利波和螺旋波速度频散曲线对地层各向异性和渗透率有不同程度的灵敏度,可用于实际资料的反演,并在此基础上处理了实钻井声波数据,对地层渗透率和各向异性进行了综合评价。研究成果可作为复杂介质地层中随钻声波测井解释的理论基础。