粗碘正庚烷一步法制备聚维酮碘粉末与传统制备工艺的对比实验研究

将粗碘正庚烷一步法制备聚维酮碘粉末与传统制备工艺进行对比实验,从反应时间、络合效率、稳定性以及杀菌效果方面进行分析与评价。结果表明,相较于传统制备方法,粗碘正庚烷一步法实现了对国内粗盐的有效利用,且具有更短的制备时间和更高的络合效率,在稳定性和杀菌效果方面也均有显著提升,是一项非常值得推广的新技术。

三种亲水性聚合物对多西他赛/磺丁基醚-β-环糊精二元体系的影响

目的:研究添加了亲水性聚合物后对多西他赛/磺丁基醚-β-环糊精二元体系的影响。方法:在多西他赛/磺丁基醚-β-环糊精中不加或分别添加1%的3种亲水聚合物,聚乙烯吡咯烷酮(PVP)、聚乙二醇(PEG)和泊洛沙姆(P188)。采用相溶解度法,于25℃、37℃和45℃下,绘制相溶解曲线,考察药物溶解度、稳定性常数(K)、络合效率及相关热力学参数。结果:PVP的加入,最有利于增强多西他赛/磺丁基醚-β-环糊精二元体系的稳定性及药物的溶解度。与固有溶解度相比,多西他赛的溶解度提高了75倍,稳定性常数从1922.84 L/mol提高到2449.44 L/mol。结论:在多西他赛/磺丁基醚-β-环糊精中加入适量亲水聚合物后可形成三元体系,提高络合效率,增加多西他赛的溶解度。

Improving Energy Performance of Water Allocation Networks Through Appropriate Stream Merging

Water-using operations in the process industry have demands for water usually both on water quality and temperature, and the existing mathematical models of heat exchange networks cannot guarantee the energy performance of a water network optimal. In this paper, the effects of non-isothermal merging on energy performance of water allocation networks are analyzed, which include utility consumption, total heat exchange load, and number of heat exchange matches. Three principles are proposed to express the effects of non-isothermal merging on energy performance of water allocation networks. A rule of non-isothermal merging without increasing utility consumption is deduced. And an approach to improve energy performance of water allocation network is presented. A case study is given to demonstrate the method.

Step-wise synthesis of work exchange networks involving heat integration based on the transshipment model

Due to the deterioration of serious energy dilemma,energy-conservation and emission–reduction have been the strategic target in the past decades,thus people have identified the vital importance of higher energy efficiency and the influence of lower carbon development.Since work exchange network is a significant part of energy recovery system,its optima design will have dramatically significant effect on energy consumption reduction in chemical process system.With an extension of the developed transshipment model in isothermal process,a novel step-wise methodology for synthesis of direct work exchange network(WEN)in adiabatic process involving heat integration is first proposed in this paper,where a nonlinear programming(NLP)model is formulated by regarding the minimum utility consumption as objective function and optimizing the initial WEN in accordance with the presented matching rules to get the optimized WEN configuration at first.Furthermore,we focus on the work exchange network synthesis with heat integration to attain the minimal total annual cost(TAC)with the introduction of heat-exchange equipment that is achieved by the following strategies in sequence:introducing heat-exchange equipment directly,adjusting the work quantity of the adjacent utility compressors or expanders,and approximating upper/lower pressure limits consequently to obtain considerable cost savings of expanders or compressors and work utility.Finally,a case taken from the literature is studied to illustrate the feasibility and effectiveness of the proposed method.

Rapid Regeneration of Chelated Iron Desulfurization Solution Using Electrochemical Reactor with Rotating Cylindrical Electrodes

A new electrochemical reactor with rotating cylindrical electrodes was designed and used to increase the regeneration efficiency of chelated iron desulfurization solution.The influence of operating parameters,such as the rotation speed of electrode,voltage,and inlet air and liquid flow rates,on the regeneration rate was investigated.Compared with the traditional tank-type reactor,the regeneration rate with the new electrochemical reactor was increased significantly.Under the optimum conditions,the regeneration rate was increased from 45.3%to 84.8%.Experimental results of continuous operation indicated that the new electrochemical regeneration method had some merits including higher regeneration efficiency,smaller equipment size and good stability in operation.

A Location-Based Content Search Approach in Hybrid Delay Tolerant Networks

In Delay Tolerant Networks （DTNs）, the offiine users can, through the encountering nodes, use the specific peer-to-peer message routing approach to deliver messages to the destination. Thus, it solves the problem that users have the demands to deliver messages while they are temporarily not able to connect to the Internet. Therefore, by the characteristics of DTNs, people who are not online can still query some location based information, with the help of users using the same service in the nearby area. In this paper, we proposed a location-based content search approach. Based on the concept of three-tier area and hybrid node types, we presented four strategies to solve the query problem, namely, Data Replication, Query Replication, Data Reply, and Data Synchronization strategies. Especially we proposed a Message Queue Selection algorithm for message transferring. The priority concept is set associated with every message such that the most ＂important＂ one could be sent first. In this way, it can increase the query success ratio and reduce the query delay time. Finally, we evaluated our approach, and compared with other routing schemes. The simulation results showed that our proposed approach had better query efficiency and shorter delay.

Energy efficient mechanism using flexible medium access control protocol for hybrid wireless sensor networks

Energy efficiency is a primary consideration in a wireless sensor network (WSN). This is also a major parameter when designing a medium access control (MAC) protocol for WSNs. Hierarchical clustering structure is regarded suitable for WSNs due to its good performance in energy conservation. In this work, an adequately flexible mechanism for clustering WSNs is designed, in which some creative or promotional metrics are utilized, such as cluster head selection algorithm, cluster optional reconstruction, interested data transmission, multiple path routing protocol. All these strategies were cooperated to maximize energy saving of whole system. An appropriate MAC protocol for this mechanism is proposed, by flexibly switching the status of diverse sensor nodes in different strategies. The simulation results show that the proposed MAC protocol is suitable for clustering WSNs and performs well in aspects of energy efficiency, flexibility and scalability.