新型阶梯式浅吃水单立柱浮式风机平台水动力分析

常规的单立柱式(Spar)风力发电机平台,在水深较浅区域工作时,结构本身受吃水限制,工作效果较差。常规Spar重心较低,具有良好的稳定性,但是由于它往往具有超过100 m的吃水,因此使其不能应用于中近海域(水深小于100 m)。可设计研究一种适用于中国东海不超过100 m水深的中近海域新型浮式风机平台以解决此问题。针对NREL 5MW风机能应用于100 m水深的情况,对50 m吃水的新型Spar(SJTU-S4)及其系泊系统进行了概念设计研究。利用商业软件建立水动力模型,进行数值仿真,同时设计缩比模型试验,在上海交通大学海洋工程国家重点实验室(SKLOE)进行水动力性能测试。结果表明,本文研究的新阶梯式浅吃水单立柱浮式风机平台在100 m水深、多种海洋波浪环境下,通过试验和仿真验证,能够具有良好的运动响应,为风机提供较好的工作条件。     

Health Phys.Abstracts,Volume 121,Number 5北大核心CSCD

Age-dependent Radiation Dose Rates from Canine Sn-117m Treatments Matthew G.Arno1,Chad Smith2(1.Foxfire Scientific,Arlington,TX;2.FX Masse,Gloucester,MA)Abstract:Tin-117m(Sn-117m)is used to treat dogs with osteoarthritic joints by radiosynoviorthesis.The decay process for Sn-117m is internal conversion wherein IC electrons and auger electrons provide the therapeutic effect.Additionally,the most prominent gamma emission is 158.6 keV.The effective dose rate received by a person interacting at close distances with a treated dog is needed to determine the person’s total dose and thus regulatory compliance.Simple measurement of the dose rate at a given distance does not provide an accurate measurement of the effective dose to a person due to the non-uniform nature of the radiation field at close distances.MNCP models of the interactions of five ages of humans at three distances were created to determine the effective dose rates using the methodology from NRC Regulatory Guide 8.40.Ratios of the effective dose rate to the person to the measured dose rate at 1 m from the same source were calculated.     

地铁不均匀沉降地段的轨道类型比选分析

简要总结了地铁不均匀沉降易发生的地段、原因及不利影响,对有砟轨道、普通无砟轨道、钢弹簧浮置板、隔振垫浮置板及梯形轨枕轨道等常用轨道类型对不均匀沉降的适应性和相关技术特点进行了全面分析,梯形轨枕在自身抗弯能力、空吊的检测和整治方便性、排水、施工速度、铺设精度等方面均具有优势,对不均匀沉降的适应性最好。     

Design and Evaluation of a Two-Layer Floating Tablet for Gastric Retention Using Cisapride as a Model Drug

A new kind of two-layer floating tablet for gastric retention (TFTGR) with cisapride as a model drug was developed. The in vitro drug release was determined, and the resultant buoyancy and the time-buoyancy curve were plotted. Because of the sodium bicarbonate added to the floating layer, when immersed in simulated gastric fluid (SGF) the tablet expands and rises to the surface, where the drug is gradually released. The in vitro drug release of this kind of two-layer dosage was controlled by the amount of hydroxypropylmethylcellulose (HPMC) in the drug-loading layer. Generally, the more HPMC, the slower the drug releases. Because cisapride has greater solubility in SGF than simulated intestinal fluid (SIF), its in vitro drug dissolution in SGF is faster than in SIF. One of the distinguishing characteristics of this kind of tablet is the separate regulation of buoyancy and drug release. The idea developed in this experiment can be used as a general model for the design of other tablets for gastric retention.     

浮动式液压剪的结构特点及参数计算

本文结合作者的浮动式液压剪的设计、调试体会,分析了液压剪的结构组成,并对液压剪设计所需的一些重要参数进行确定。     

可拆卸式浮动切刀在修边模具中的应用

分析了现有废料切断结构存在的问题及其产生的原因,并针对其弊端提出了一种可拆卸式浮动切刀结构。介绍了可拆卸式浮动切刀的组成、冲裁力的计算、行程和工作过程。该结构不仅提高了产品的表面质量,而且拆卸方便,冲压稳定,极大地提高了工作效率。     

一种对三维芯片中硅通孔进行完整建模与寄生参数提取的有效方法

针对三维芯片中硅通孔（through-silicon via, TSV）的准确电学建模问题,本文提出了一种电阻电容（RC）电路模型以及相应的有效参数提取技术。该电路模型同时考虑了半导体效应与静电场影响,适合于低频与中频的电路信号范围。该方法采用一种基于悬浮随机行走（floating random walk, FRW）算法的静电场电容提取技术,然后将它与刻画半导体效应的MOS电容结合,形成等效电路模型。与Synopsys公司软件Sdevice所采用的对静电场/半导体效应进行完整仿真的方法相比,本文方法计算效率更高,并且也能处理一般的TSV电路版图。对多个含TSV的结构进行了计算实验,结果验证了本文方法在从10KHz到1GHz频率范围内的建模准确性,也显示出它相比Sdevice方法最多有47倍的加速比。     

聚苯胺@粉煤灰漂珠复合材料的导电及介电性能

为获得具有良好电流变性能的分散相粒子,利用γ-氨基丙基三乙氧基硅烷(APTES)修饰粉煤灰漂珠(FAFB),将聚苯胺(PAn)以化学键的方式偶联在修饰后的FAFB(mod-FAFB)表面,形成以mod-FAFB为核、PAn为壳的核-壳结构复合材料。采用FTIR、SEM、数字式四探针以及LCR介电谱仪对PAn@mod-FAFB复合材料的结构与性能进行分析,讨论了不同mod-FAFB含量对PAn@mod-FAFB复合材料导电性能及介电性能的影响。结果表明:以化学键接枝聚合的PAn@mod-FAFB核-壳结构复合材料电导率相对较高,且随mod-FAFB含量的增加而减小;在较低交变电场频率(100~2 000kHz)下其相对介电常数较大,且随mod-FAFB含量的增多,PAn@mod-FAFB复合材料的介电常数明显减小;PAn@mod-FAFB复合材料的介电损耗相对较小,随mod-FAFB含量的增多而急剧减小。     

一种新型有源调压变换器的实现

针对目前普通的电压调整模块的变换器存在输入、输出电压变化量大、变换效率低、占空大等问题,提出了一种带有源浮充平台新型电压调整模块,该模块具有稳定的调压率,同时模块能在不采取均流的情况下自动调节平衡各相感应电流提高其效率,精简了控制电路。对新模块进行了稳、动态试验验证,验证结果证明了新模块理论的正确性。