杭州市钱江四桥主桥施工图总体设计

钱江四桥为双层双主拱钢管混凝土组合系杆拱桥,主桥共有11跨.本文详细介绍了桥梁施工图总体设计和各部分构造及施工方案.     

杭州市钱江四桥190 m跨钢系梁设计

杭州市钱江四桥190 m跨系梁采用2500×2500mm的钢箱梁,钢系梁与主拱肋共同形成拱梁组合受力体系,并与下层吊杆横梁一起形成梁格体系,承受下层桥面荷载;钢系梁同时也作为预应力钢绞线成品索系杆的保护和定位装置.本文详细介绍了钢系梁的总体布置、主要构造.     

Neutronic Comparison of Tritium－Breeding Performance of Candidate Tritium－Breeding Materials

Tritium self-sustainment, which will meet the fuel requirement of fusion reactor, is one of the key issues of fusion power development. The tritium breeding performances of various tritium-breeding materials are compared based on a series of neutronics calculations using three-dimensional Monte Carlo neutron-photon transport code MCNP/4C with the IAEA FENDL-2 data library. The effects of the dimensions of the tritium-breeding zone and the enrichment of 6Li on Tritium Breeding Ratio (TBR) are analyzed. The effects of Be as a neutron multiplier on TBR are also calculated.     

高校图书馆思想政治教育职能的特点与发挥

浅析了高校图书馆思想政治教育职能的特点与对策，并就如何有效地履行这一职能以及履行这一职能的根本保证等方面阐明了作者的观点。     

电脑烧烤VCD全过程

今天突然接到一份邮包,打开之后发现是一张其貌不扬的光盘,反正我也正无聊,于是放到电脑中看了起来……啊!太意外了,这竟然是一张小学好友从英国邮寄回来的DVD光盘,更不可思议的是里面竟然是他的生活照片!于是我想到了一个问题,他是如何将自己的照片刻录到DVD中,并且还能够直接     

后冰箱时代:比谁更招人喜欢——2003年榕城家用冰箱产品消费行为调查

冰箱从诞生到现在已经79年了。在过去的这半个多世纪里,越来越多的人享受着冰箱带给自己生活的巨大便利,冰箱也已成为现代家庭生活中不可或缺的一员。据统计,2001年城镇每百户居民冰箱拥有量已达到了82.6台,省会城市每百户居民的拥有量已经超过90台。     

聚变驱动次临界堆双冷嬗变包层结构设计与分析

给出聚变驱动次临界堆液态金属LiPb/He气双冷嬗变包层参考结构概念,采用了低活化铁素体/马氏体RAFM钢(如CLAM)作为结构材料、简单液态金属流道、两个独立氦气冷却系统以及燃料球/颗粒等设计方案。重点分析了嬗变包层第一壁、重金属区与裂变产物嬗变区的结构设计特点。     

Flow Control over a Conical Forebody by Duty-Cycle Actuations

Duty-cycle modulation alternately blowing from two opposite-facing plasma actuators on the leeward surface near the apex of a cone with a 10 semi-apex angle is adopted to control mean lateral force and moment, and the flow control mechanisms are presented. Pressure distributions over the forebody of the cone are measured by steady pressure tappings. The experiments are performed in a 3.0×1.6 m open-circuit wind tunnel at a wind speed of 20 m/s, a 45 angle of attack and a Reynolds number of 2×10 5 , based on the diameter of the base of the cone. Almost linearly proportional control of the lateral forces and moments over a slender conical forebody at a high angle of attack has been demonstrated by employing a pair of single dielectric barrier discharge plasma actuators near the apex of the cone, combined with a duty-cycle technique. The pressure distribution measurements indicate that the bi-stable vortex pattern appears to be shifted in the opposite direction when the port or starboard actuator is activated, while the other is kept off during the test. It is shown that the reduced pulse-repetition frequency based on the local diameter at the plasma actuator equal to one yields the highest effectiveness among the cases considered.     

硝酸铀酰光化还原的研究

本文的目的是探讨光化还原制备硝酸钠(Ⅳ)。研制了一个与硝酸钠酰的吸收光谱匹配较好的金属卤化物灯——镓灯作为激发光源,在不另加滤光器的条件下,对几种还原剂的还原能力作了比较,并对乙醇作还原剂时,硝酸浓度、乙醇浓度、初始铀酰离子浓度以及温度等因素对光化还原铀(Ⅵ)到铀(Ⅳ)的还原率的影响进行了研究。