加味增液汤对复方地芬诺酯诱导的便秘小鼠的影响

目的: 考察在增液汤（包括玄参、生地、麦冬）基础上增加铁皮石斛和/或生白术对复方地芬诺酯诱导的便秘小鼠的影响。方法: 采用复方地芬诺酯建立小鼠便秘模型,制备增液汤+生白术+铁皮石斛、生白术+增液汤、增液汤水煎液及麻仁胶囊溶解液,分别灌胃给药后检测便秘小鼠排便、小肠推进情况及血清超氧化物歧化酶（SOD）活力。结果: 增液汤+生白术+铁皮石斛与生白术+增液汤促进排便及小肠推进的疗效优于增液汤及麻仁胶囊溶解液;增液汤+生白术+铁皮石斛可显著提高便秘小鼠血清SOD活力,优于增液汤及麻仁胶囊溶解液。结论: 生白术（或生白术+铁皮石斛）可增强增液汤对复方地芬诺酯诱导的小鼠便秘的疗效,铁皮石斛+生白术+增液汤可提高便秘小鼠血清SOD活力。     

特高压直流闭锁后超（超）临界机组大频差控制策略

特高压直流输电系统发生直流闭锁故障时,受电端电网瞬间损失功率必须依靠区域内电厂调频来弥补,火电机组的作用尤为关键,现阶段火电厂多为高参数大容量机组,机组的蓄能非常有限,电网直流闭锁故障引发的大频差一次调频动作时,火电机组一次调频贡献电量受到机组蓄能的影响,不利于电网事故的快速恢复,还可能引起电网频率的振荡。以目前比较典型的600 MW等级火电机组为例,在皖电东送田集电厂进行大频差时一次调频和协调控制策略的相关试验,研究优化方向,采用了形式多样的新型控制策略,改善机组协调控制和一次调频性能,提高事故状态下火电机组对电网的贡献度。     

NP树脂的合成及其对铀吸附性能实验研究

用天冬酰胺对脲醛树脂进行改性,合成天冬酰胺改性类蛋白氨基螯合树脂(NP树脂),用于废水中铀的富集,以提高水中铀的监测速度。结果表明:在F/U摩尔比为0.8,天冬酰胺加入量为5%的前提下合成NP树脂,该树脂在25 ℃、pH值约为5、平衡时间为210 min时其吸附容量为46.98 mg/g。     

A hierarchical approach for the synthesis of batch water network

This work addresses the problem of synthesising cost-effective batch water networks where a number of process sources along with fresh water are mixed, stored, and assigned to process sinks. In order to address the complexity of the problem, a three-stage hierarchical approach is proposed. In the first stage, global targets are identified by formulating and solving a linear transportation problem for minimum water usage, maximum water recycle, and minimum wastewater discharge. These targets are determined a priori and without commitment to the network configuration. Next, a network with minimum number of tanks is synthesised by solving a mixed-integer non-linear program. The bilinear constraints are relaxed to transform the program into a mixed-integer linear program that is globally solvable. The third stage is aimed at simplifying the network configuration by minimising the number of network inter-connections. Insights gained from the water pinch analysis are also incorporated into the approach to further reduce the water flows via the placement of water regeneration unit. A case study is solved to illustrate the effectiveness of the proposed procedure.     

Modeling the Nonlinear Behavior of Concrete Masonry Walls Retrofitted with Steel Studs under Blast Loading

This paper presents the results of an analytical investigation of one-way unreinforced masonry (URM) walls retrofitted with externally anchored steel studs and subjected to blast loads. Using the wall geometrical and material properties, deflected shape, and crack pattern as input, a nonlinear model is developed to predict the inward force-displacement relationship of the retrofitted walls. In addition, using a rigid body analysis, a simple bilinear force-displacement relationship is developed to model the outward force-displacement relationship of the walls. Utilizing these two force-displacement relationships (resistance functions), a generalized single-degree-of-freedom (SDOF) model is developed to capture the nonlinear out-of-plane dynamic response of the retrofitted walls under blast loads. The SDOF model captured the experimentally observed displacement responses of the tested walls with reasonable accuracy. The model was also used to investigate the influence of block thickness, wall slenderness ratio, blast load intensity, and blast pulse shape on the out-of-plane dynamic response of retrofitted walls. The results demonstrated that anchored steel-stud systems could significantly enhance the out-of-plane capacity of the retrofitted walls by increasing their out-of-plane capacity and reducing their displacement.     

Performance of Unreinforced Masonry Walls Retrofitted with Externally Anchored Steel Studs under Blast Loading

Six full-scale concrete masonry walls were tested under free-field blast loading using different charge sizes up to 250?kg of ammonium nitrate/fuel oil (ANFO) and at a constant stand-off distance of 15.0?m to cover a wide range of expected damage levels. Five walls were retrofitted with cold-formed steel studs anchored to the wall backs and were compared to the remaining as-built wall. Significant enhancement to the out-of-plane blast resistance of the retrofitted walls, compared to the as-built wall, was observed. This enhancement is attributed to the development of a tied-arch action in the retrofitted walls in which the masonry forms a compression strut while the steel studs serve as the tie. A simplified single-degree-of-freedom model was used to analyze the experimental results, and the model results agreed well with the observed damage levels and the resistances of the walls. In addition, the effectiveness of the proposed retrofit technique was evaluated in terms of strength enhancement and wall deflection reduction. The test results were also compared with those predicted by available blast damage assessment models for unreinforced masonry walls. However, it was found that available models, which do not account for the tied-arch mechanism, greatly underestimate the actual blast capacity of the retrofitted walls because of the assumption of a tensile flexural failure mode. Additionally, the proposed retrofit technique shifts the mode of failure from flexure to shear.     

An extended graphical targeting technique for direct reuse/recycle in concentration and property-based resource conservation networks

Minimum flowrate targeting methods for resource conservation networks (RCNs) have been developed over the last decades. The existing methodologies still have certain drawbacks. Their design insights could be deepened and some steps should be more convenient for the users. A targeting tool called the material surplus composite curve (MSCC), which is an improvement of the surplus diagram for water and hydrogen networks is introduced. The approach is illustrated on several cases selected from the literature. Using this technique, it is possible to determine rigorous flowrate targets for different variants of the RCN problem.     

Unraveling the daily stress crossover between unemployed individuals and their employed spouses.

This study examined the dynamic relationship of distress levels between spouses when one is unemployed (and looking for a job) while the other is engaged in full-time employment. Using the diary survey method, we sampled 100 couples in China for 10 days and tested a model comprising three stress crossover mechanisms: the direct crossover, the mediating crossover, and the common stressor mechanisms. Results supported the direct crossover and common stressor mechanisms. Other stressors (e.g., work–family conflict and negative job search experience) were also related to distress of the unemployed individuals and their employed spouses. Additionally, we found a three-way interaction involving gender, marital satisfaction, and distress levels of employed spouses. We discuss how the study contributes to the unemployment and stress crossover literatures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)