Thermal conductivity of granular rice starches

Thermal conductivities of four types of granular rice starches, regular, low protein, waxy and low protein waxy, were measured at bulk densities of 600 and 800 kg/m³, temperatures of 20, 50 and 80 °C, and moisture contents of 4, 20 and 40% (wet basis), using a line‐source thermal probe system equipped with a computerized data acquisition system. A completely randomized experimental design with factorial treatment structure resulted in a total of 72 treatments, each with 3 replications. The thermal conductivity was significantly different among various rice starches. Low protein and waxy rice starches had higher thermal conductivities than regular and low protein waxy rice starches. Thermal conductivity increased significantly with increases in bulk density, temperature and moisture content. Prediction models were developed to calculate thermal conductivity values for practical applications.     

饱和层状砂土地震液化特性模拟与改良

探究在地震作用下饱和层状砂土液化规律,并通过设置抗液化桩、隔振墙等装置,研究该装置 对土体的抗液化性能的影响。文章基于基底压应力法算得静力部分的各土层位移量,同时基于液化判 别准则和理论,结合辽宁省文化艺术中心和省博物馆新馆工程背景,应用有限元软件,通过选取峰值加 速度为 0．6ｇ的水平向 Ｋｏｂｅ地震波进行计算,对各土层位置超孔压比、超孔隙水压力和有效应力等进行 研究,对此时各层位置土体的液化情况进行对比分析。得到了抗液化桩、隔振墙能不同程度地减小土体 地震液化响应的结论。     

多功能防喷装置的研制及现场应用

根据井下试油施工无钻台作业防喷装置在现场使用方式的不同,详细介绍了几种防喷装置的结构、原理和使用方法。以实例对比分析了几种防喷装置的优劣,指出防喷总成C不适应现场操作,推荐使用多功能防喷装置的防喷方法,它具有使用方便,安全可靠,省时省力等优点。     

无固相气井储层保护液在克拉美丽气田中的应用

随着新疆油田克拉美丽气田的不断开发,高压高产气井的储层保护越来越受到重视。为了降低固相物质及入井液滤失对气藏的伤害,研究开发了无固相气井储层保护液。该储层保护液具有体系无固相、密度调节范围大、低滤失、低粘度、低伤害、性能稳定等特点,密度在1．0g／cm3～2．30g／cm3。滴西17高压气井大修套管补贴作业,在打开气层情况下选用密度1．50g／cm3的无固相气井储层保护液作为修井液,在无固相气井储层保护液中套管补贴2段射孔段,修井作业15天,无固相储层保护液体系均一、性能稳定,保证了修井作业顺利完成,取得良好效果。     

射孔参数对水力压裂效果的影响实例分析

低孔低渗储层需要通过压裂改造才能获得产能,而射孔参数的选择直接影响到低孔低渗储层压裂改造的效果及成功率。通过研究射孔参数对压裂施工影响及现场应用实例对比,得出：射孔深度对施工压力有一定影响,但是影响较小;射孔方位影响到施工压力、裂缝转向以及裂缝形态,它影响到施工的成败;射孔高度影响压裂改造效果．尤其是对有底水的复杂储层。     

基于几何约束的平面连杆机构通用仿真软件设计

把平面连杆机构用"基本坐标"和"连杆约束"表达为最小二乘问题,通过求解非线性方程组的形式对连杆机构的几何约束进行求解,并采用可视化搭建结果和仿真状态结果作为迭代初值,很好的解决了一般方法对迭代初值的敏感性.最后在Matlab/GUI平台上开发出通用的仿真软件,并给出了几种常见连杆机构的仿真结果.     

自动气象站的实时数据传输控制策略

针对自动气象站数据采集的实时性和及时性要求,考虑GPRS传输网络在线状况、数据丢包、乱序以及蓄电池欠压、中心站监控负担等情况,从数据传输实时检测机制和蓄电池欠压情况下的动态电源管理模式两个方面,提出一种气象数据实时传输控制策略,提高数据传输的实时性和及时率。实践证明该策略实施的可行性和有效性,为应急气象灾害预报服务获取实时的、及时的气象采集数据提供有效保障。     

Preliminary study of the stiffness enhancement of wood–plastic composites using carbon nanofibers

Vapor-grown carbon nanofibers (CNFs) were compounded into polypropylene (PP) with southern pine wood flour (WF) by high shear melt blending to investigate the reinforcement effects of CNFs on the stiffness of conventional wood flour/plastic composites. CNF loadings of 1, 2 and 5 parts by weight per 100 parts of PP were employed with three WF levels (20, 40 and 60 parts). Maleated polypropylene (MAPP) was used as a coupling agent to improve WF to PP compatibility. The incorporation of CNFs significantly increased the modulus of elasticity of these nanocomposites with MAPP addition. The presence of 0.61 wt?% of CNF within a 36.6%WF/1.83%MAPP/61%PP composite exhibited a modulus (7590 MPa) that was 59% greater than its counterpart without CNF (36.8%WF/1.84%MAPP/61.4%PP) (4783 MPa) and 90% greater than pure PP. The origin of this enhancement is not yet understood.     

Performance Analysis Applications in Virtual of Interactive Desktop Machine Environment

To assess the feasibility of hosting interactive desktop applications in virtual machine environment, this paper measures and analyzes the interactive performance of the desktop operating system in Xen environment. The experimental results show that short-latency input events are not sensitive to the virtualization overhead but the average response latencies of long-latency events in Xen system are remarkably longer than the latencies in the unvirtualized system. In fact, the larger variance of response latency, instead of the longer latency itself, is the most important performance problem for the virtualized approach. Our analysis shows that the main reason of the poor performance is the insufficient CPU share of the driver-specific virtual machine, which causes the long freezing periods of other guest virtual machines. While the offline adjustment can alleviate the problem, an online adaptive adjustment of the CPU allocation is necessary for the practical use of Xen hosted desktop systems.     

YBZSE防爆双速电动机控制电路的接线

<正>随着我国石油化工工业的迅猛发展,防爆起重机不断得到研制开发并应用于该领域,YBZSE防爆电动机多用于起重机的双速控制及制动,具有较大的过载能力和较高的机械强度,因此它特