注气井中油管轴向位移计算比较分析

为了确定油管在正常作业、注入措施作业中封隔器的坐封位置、轴向位移补偿量以及判断封隔器是否解封,根据弹性力学理论得出了不同条件下油管柱的轴向位移量,综合考虑了在不同工况下由活塞效应、螺旋弯曲、径向压力、温度变化、松弛力以及摩阻等因素引起的油管轴向位移;同时考虑了在注气油管内气体的横向压力效应,运用VB语言编制程序,将各自计算结果进行了比较分析。结果表明,在注气油管内考虑横向压力效应时与常规油管长度计算油管轴向位移有明显差异;油管内液体流动引起的油管轴向伸长与注入速度的平方成正比,在注入速度过大时对轴向位移有明显影响。     

Investigation on the Recrystallization Behaviour of Cold Deformed MP159 Alloy

The recrystallization behaviour of cold drawn MP159 alloy was investigated by optical and TEM examinations. It is found that the platelet ε phase in the MP alloy inhibits the recrystallization,and this effect makes the MP159 alloy with high recrystallization temperature of about 920℃.This inhibition mainly comes from the increasing of the interfacial energy, which results from the change of the coherent interfaces of (0001)hcp//(111)fcc into the incoherent interfaces when the recrystallizing grain fronts bypass the platelet ε martensite. The increasing of the interfacial energy also causes the dissolution of a few segments on the ε martensite platelets, which decreases the strength of the MP alloy     

二次加热和冷却方式对过共晶铝硅合金半固态组织的影响

过共晶Al 17%Si 4.5 %Cu 0 .5 %Mg合金通过Sr优化变质处理获得初晶硅细小且有α枝晶的显微组织。在固液两相区保温 ,结合金相分析研究组织的转变规律 ,结果表明 :共晶硅经历着熔断、粒状化和粗化的过程 ,初晶硅有长大的趋势 ;随着保温时间的延长 ,共晶体不断熔化成液相 ,液相体积分数逐渐增加 ,直至液相薄膜包围着α相 ,α相由不规则形状向球状转化 ,α相的粗化和合并几乎同时进行 ,最终获得非常理想的半固态组织。从形状系数和等效直径两个方面评价了近球形α相的特征。     

室温磁制冷材料La（Fe0.94Co0.06）11.7Si1.3在去离子水中腐蚀行为的研究木

针对La（Fe0.94Co0.06）11.7Si1.3磁制冷材料在去离子水中的腐蚀行为进行了研究，结果表明，腐蚀速率随时间的变化而变化，开始时腐蚀速率较快，随着时间的延长，腐蚀速率逐渐变慢。XPS能谱分析表明，腐蚀产物主要由γ-Fe2O3、Co（OH）2及H2SiO3组成，产物形态较为疏松，不足以对基体形成有效保护。腐蚀产物中没有发现La的信息，其具体原因有待在后续工作中进一步深入探讨。     

甲醇氧化制甲醛铁钼催化剂的研究

采用共沉淀法制备甲醇氧化制甲醛无载体铁钼催化剂,并考察了催化剂制备老化条件、焙烧温度、外型尺寸以及活性测试反应温度、空速对催化剂性能的影响。该催化剂在280~300℃、气空速7000 h-1~8000 h-1、进料φ(甲醇)为5.5%的下,可获≥98%的甲醇转化率,≥92%的甲醛选择性和≥90%的甲醛产率。催化剂活性高,强度好,性能稳定。     

巴基斯坦高摩赞水利枢纽工程项目危机处理及合同谈判

高摩赞工程项目是水电集团公司在巴基斯坦承建的第一个综合性的水利水电枢纽工程,也是第一个EPC合同形式的项目。本文主要介绍了项目危机处理及合同谈判的过程和措施,通过长达一年的艰苦谈判,化解了项目危机,增进了中巴传统友谊,实现了良好的经济效益和社会效益,为中国水电集团公司国际化战略发展提供了可借鉴的成功案例。     

Neuronal units linked to microvascular modules in cerebral cortex: response elements for imaging the brain

How neuronal activity changes cerebral blood flow is of biological and practical importance. The rodent whisker-barrel system has special merits as a model for studies of changes in local cerebral blood flow (LCBF). Stimulus-evoked changes in neural firing and 'intrinsic signals' recorded through a cranial window were used to define regions of interest for repeated flow measurements. Whisker-activated changes in flow were measured with intravascular markers at the pia. LCBF changes were always prompt and localized over the appropriate barrel. Stimulus-related changes in parenchymal flow monitored continuously with H2 electrodes recorded short latency flow changes initiated in middle cortical layers. Activation that increased flow to particular barrels often led to reduced flow to adjacent cortex. Dye was injected into single penetrating arterioles from the pia of the fixed brain and injected into arterioles in slices of cortex where barrels were evident without stains. Arteriolar and venular domains at the surface were not directly related to underlying barrels. Capillary tufts in layer IV were mainly coincident with barrels. The matching between a capillary plexus (a vascular module) and a barrel (a functional neuronal unit) is a spatial organization of neurons and blood vessels that optimizes local interactions between the two. The paths of communication probably include: neurons to neurons, neurons to glia, neurons to vessels, glia to vessels, vessels to vessels and vessels to brain. Matching a functional grouping of neurons with a vascular module is an elegant means of reducing the risk of embarrassment for energy-expensive neuronal activity (ion pumping) while minimizing energy spent for delivery of the energy (cardiac output). For imaging studies this organization sets biological limits to spatial, temporal and magnitude resolution. Reduced flow to nearby inactive cortex enhances local differences.     

基于Silverlight的富数据输入研究

针对站点中经常需要用户输入各类数据的现状,讨论了实现开发RIA应用的Silverlight技术以及ASP.NET/SilverlightWeb应用程序的N层逻辑设计,并在此基础上利用Silverlight技术较好地实现了电子商务RIA平台中一个富数据输入界面功能,提高了用户的体验。     

A novel compact low-power direct conversion receiver for mobile UHF RFID reader

A novel direct conversion receiver with low cost and low power is implemented in a 0.18 μm 1P6M standard CMOS process for a Mobile UHF RFID reader.A highly linear active mixer with low flicker noise and low noise active load is proposed.An efficient and low cost on-chip DC offset voltage canceling scheme is adopted with a high-input-impedance four-input OPAMP to buffer the output of the DC offset canceller(DCOC) block.The receiver has a measured input 1 dB compression point of 2 dBm and a sensitivity of 72 dBm in the presence of the large leakage signal from the transmitter.Only occupying a silicon area of 2.5 mm 2 and consuming 21 mA from a 1.8 V supply,the receiver makes the mobile UHF RFID reader to communicate with a transponder in a distance of 1 m conveniently.