南水北调穿漳工程围堰深厚砂卵石层防渗施工

南承北调穿漳围堰为临时性工程,所处位置砂卵石层深厚.对于其防渗施工,综合电力、工期、环境影响、防渗效果与投资等因素,最终选择了以防为主、防排结合的帷幕灌浆施工方案.施工中采取潜孔锤与岩芯钻机相结合的钻孔方法,采用自下而上分段、管口封闭、孔内循环的方式进行灌浆,保证了施工质量,加快了施工进度,确保了节点工期.     

Experimental and numerical analysis of oil shale drying in fluidized bed

The main objective of this work was to experimentally and numerically investigate the Liu Shu River oil shale drying by the means of flue gas in a fluidized bed dryer. Several experiments were performed under different temperatures conditions. The moisture content of oil shale was measured during the experiments. The two-stage drying model was incorporated in computational fluid dynamics (CFD) package FLUENT via user-defined functions (UDF) and utilized for simulation of heat and mass transfer of oil shale drying in the fluidized bed dryer. The simulation results for solid moisture content agreed well with experimental data. The effects of the temperature and velocity of flue gas, initial bed height, and the particle size on the drying characteristics were predicted and analyzed. It is shown that the gas temperature and velocity are the important parameters in the whole drying process. The particle size has more obvious influence in the falling drying period than the constant drying period. The temperatures of gas and solid phases were monitored. It is shown that the so-called “near gas distributor zone” is the most effective heat transfer zone, which agrees well with the calculated value. The system quickly reached thermal equilibrium, characterizing a nearly isothermal bed. The developed model provides a very good demonstration to describe the oil shale drying in the fluidized bed dryer, and may provide important information for design, optimization of operation conditions.     

混炼胶熔体的挤出膨胀研究

依据粘弹性熔体流变学理论，采用张量分析方法，研究了混炼胶熔体在挤出过程中的膨胀行为。推导出以剪切形变为主，挤出物膨胀率；以拉伸形变为主，挤出物膨胀率。在理论上进一步论证收敛拉伸流变是导致混炼胶熔体挤出物膨胀率较大的原因。     

基于SPSO与ISKPCA的RdR散点图识别分类研究

面对稀缺的医疗资源,心血管疾病的上升趋势,自动化诊断日趋迫切。为实现心电自动化诊断,提出了一种使用简化粒子群算法来自动搜寻集成稀疏核主分量分析的参数,并以此获得的集成稀疏核主分量分析模型来对用心电数据绘制的RdR散点图进行识别分类的方法,以期实现心电自动化诊断。算法通过计算样本数据与使用核主分量分析映射数据之间的距离差值来研究数据之间的最大相似性,并以此来判断样本数据类别,在对正常窦性心律、非偶联早搏、二联律早搏、三联律早搏以及混合早搏这五种心律进行的分类实验结果显示,可以准确识别不同的心律,分类的正确率较高,有助于心电自动化诊断的实现。     

Nitrogen loss and rice profits with matrix-based slow-release urea

Paddy fields account for a large proportion of cultivated land, with huge N consumption each year. Reducing N loss via application of low-cost slow-release fertilizers is beneficial for eco-friendly rice production. The current study aimed to investigate the effects of matrix-based urea on soil N availability, rice yield, agronomical efficiency (AE), and rice profits. A 2-year field experiment was conducted during 2015 and 2016 following a randomized block design. It included three treatments, i.e., control test (CK, without urea application), common urea (CU, 150 kg N ha^?1), and matrix-based urea (MU, 150 kg N ha^?1). Besides, three laboratory experiments were conducted to investigate the N leaching, ammonia volatilization, and slow-release mechanism. Results showed that application of MU increased rice yields by > 10%, biomass by > 6%, and AE by > 30% in both seasons. Greater yield, biomass, and AE in MU were largely attributed to higher soil available N, resulted from lower risk of N leaching and ammonia volatilization. Aggregate structure was partly responsible for lower N loss in MU. Greater soil available N in MU increased rice height, leaf area, root area, leaf total chlorophyll, and activity of nitrate reductase and glutamine synthetase in flag leaves, and thus favored rice growth. Compared with CU, MU increased fertilizer cost by about 23 USD ha^?1, but increased rice profits by > 230 USD ha^?1 due to greater yield. Overall, matrix-based urea is suitable for application in field rice production, due to its low risk of N loss and acceptable profitability.     

血液流动性的计算机可视化测定及其技术应用

简要描述了日本MCFAN研究所生产的血液流动性可视化检测仪的测定原理、实验方法和临床应用。血液流动性的可视化测定仪（以HR300型为例）将进样系统、计算机处理系统、显微摄像等一体化（Micro Channel Array Flow Analyzer,MCFAN）,使操作繁琐的血液流变性观察检测变得简便易行,并通过液晶显示器可观察到血流的状态,具有直观形象的特点。广泛用于预防医学、药物研究、疾病诊断和健康教育等领域,并为大众健康咨询提供了直接支持,本文比较全面的介绍了血液流动性的检测方法及其临床应用。     

纤维素基功能材料

纤维素是地球上最为丰富的生物质资源,具有易降解、可再生、无毒性且廉价易得等优点,可以代替石化资源生产各种高附加值功能材料。从纤维素资源利用出发,综述了近年来纤维素基功能材料的最新研究进展,重点介绍4种主要形态纤维素材料的功能及其应用。内容包括：纤维素多孔微球合成和孔结构调控,及其在吸附分离和药物释放领域的研究进展;纤维素水凝胶和气凝胶及其在医用、诊断、电极、分离材料领域的最新开发与应用进展;其他纤维素基功能材料,如高透光度和高韧性的纤维素膜、高韧性和可编织性的纤维素纤维材料,以及在纺织、光电及智能材料领域的应用。最后对纤维素基功能材料的未来发展提出一些设想,并讨论了在发展过程中面临的关键科学问题,为纤维素基功能材料下一步的研发和应用提供有价值的参考和指导。     

基于DSP的电力VOIP系统嵌入式安全终端设计

为实现电力VOIP系统的安全通信,确保电力调度的语音、视频图像的可靠传输,设计了一种基于DSP的电力VOIP系统安全终端。该安全终端由软件系统和VOIP安全通信平台组成;在硬件设计上,以OMAP-L137DSP为核心处理器,用安全芯片、噪声源芯片等辅助处理器实现系统的密钥算法,采用智能卡认证机制确保用户身份的合法性。在软件设计上,给出了电话模块与安全模块之间通信的数据帧格式,介绍了系统的流媒体交互方式,提出了一种基于身份签名的通信双方双向认证的密钥协商算法。通过系统测试表明,该VOIP安全终端的数据处理速度为52.312Mbps,满足电力系统实时调度通信的要求;密钥协商阶段平均耗时627ms,明码通信与加密通信的转换效率高;多台终端间网络视频通话的声音清晰逼真,画面无明显失真;该系统可扩展性和可移植性强,具有很好的应用推广价值。     

Reactor core transient analysis of an innovative high‐level nuclear waste transmuter with metal fuel

For the sustainable development of nuclear energy, reducing high‐level nuclear wastes in spent fuels discharged from commercial nuclear power plants is very important. Partitioning and transmutation of minor actinides from these spent fuels are critical for the effective disposal of high‐level wastes. However, transmutation in current operational reactors is not efficient and brings some safety problems. Therefore, a dedicated accelerator‐driven subcritical transmuter named highly efficient industrial transmuter (HEIT) was newly proposed to solve the problems. This system utilizes the uranium‐free metallic dispersion fuel and is of high power density. This paper focuses on the transient analysis of HEIT to prove that it is feasible for the future nuclear industry. Temperatures, cladding stresses, and cumulative creep damage fractions are analyzed. Furthermore, the burnup dependence is also investigated. Three typical transients including the unprotected loss of flow, the beam overpower (BOP), and the unprotected transient overpower are evaluated. Numerical results conclude that in the reactivity insertion transient and the BOP transient, this new system exhibits excellently in safety. However, the shut‐down system is required in flow loss case which lasts more than half an hour. The safety margin changes with core depletion. For unprotected loss of flow, the end of lifetime case is the most important one to care. While for BOP and unprotected transient overpower, both the beginning and end of lifetime should be accommodated. The conclusions will be useful in the future design of HEIT and similar systems. Copyright © 2017 John Wiley & Sons, Ltd.     

稻草水解液与乙腈的双水相分配特性

研究了稻草水解液中的糖在乙腈-水双水相体系中的分配行为,首先重点考察了双水相的形成,分析了乙腈与稻草水解浓缩液的体积比和温度等对糖的分配系数影响。乙腈体积分数低于50%时不能形成双水相。当V乙腈:V样品等于2或者3时,在25℃下实验,上层富含乙腈相中有葡萄糖、还原糖以及多糖同时存在,特别是当V乙腈:V样品等于3时,81.56%的葡萄糖提取到乙腈相中。在0℃下实验,上层富含乙腈相中都只检测到多糖。