柴油无污染脱酸精制工艺研究

采用三组分溶剂对胜利柴油馏分进行了溶剂脱酸精制研究，考察了精制过程的最佳工艺条件．在剂油比为０．２５～０．３∶１、常压、温度为３０～５０℃的条件下，可将酸度小于１２０ｍｇＫＯＨ／１００ｍＬ的柴油，降至５ｍｇＫＯＨ／１００ｍＬ以下，达到优等品标准，且不影响馏分组成和闪点．萃取液在蒸发前可直接使用３～４次再去蒸发．直接回收得到的环烷酸酸值达１９０ｍｇＫＯＨ／ｇ左右，纯度达９０％以上     

高速弧齿锥齿轮动频计算

建立了旋转轮盘动力学模型，提出了基于刚度矩阵的离心刚度矩阵修正了模式下的动频求解有限元法，实现了弧齿锥齿传频的数值求解，数值计算与实测值基本一致且由算例得出结论，旋转效应对低阶模态，节径型振型影响较大，本算法对旋转轮盘类的动频计算具有通用性。     

Antioxidant survey to assess antagonism to redox stress using a prokaryotic and an eukaryotic system

Using a prokaryote (Escherichia coli) and a metazoa-resembling eukaryote (Ochromonas danica), we surveyed antioxidants which might overcome redox stress imposed by menadione sodium bisulphite (MD) and buthionine sulphoximine (BSO). BSO oxidant stress was evident only inO. danica; MD oxidant stress was evident in both organisms. Glutathione, its precursors, e.g. cysteine, homocysteine, and 2-oxo-4-thiazolidine carboxylic acid, and red blood cells, emerged as prime antioxidants for relieving BSO and MD oxidant stress. BSO and MD oxidant activity and antioxidant-annulling effect inO. danica were judged comparable to those found in animal cells whereas the resultsE. coli were not entirely equivalent. TheO. danica system emerged as a practical, rapid, and useful system for pinpointing oxidant stressors and antioxidants, and shows promise for studies with mammalian systems.     

(−)-Epigallocatechin gallate,a polyphenolic tea antioxidant,inhibits peroxynitritemediated formation of 8-oxodeoxyguanosine and 3-nitrotyrosine

Reaction with peroxynitrite at pH 7.4 and 37°C was found to increase the 8-oxodeoxyguanosine levels in calf thymus DNA 35-38-fold. This oxidation of deoxyguanosine, as well as the peroxynitrite-mediated nitration of tyrosine to 3-nitrotyrosine, was significantly inhibited by ascorbic acid, glutathione and (–)-epigallocatechin gallate, a polyphenolic antioxidant present in tea. For 50% inhibition of the oxidation of deoxyguanosine to 8-oxodeoxyguanosine, 1.1, 7.6 of 0.25 mM ascorbate, glutathione or (–)-epigallocatechin gallate, respectively, was required. For 50% inhibition of tyrosine nitration, the respective concentrations were 1.4, 4.6 or 0.11 mM. Thus, (–)-epigallocatechin gallate is a significantly better inhibitor of both reactions than either ascorbate or glutathione. Reaction of (–)-epigallocatechin gallate with peroxynitrite alone resulted in the formation of a number of products. Ultraviolet spectra of two of these suggest that the tea polyphenol and/or its oxidation products are nitrated by peroxynitrite.     

工业化初期墨西哥地方市政府决策之经济人类学研究

向城市贫困人口提供廉价的生活物资和基本服务是发展中国家面临的一个主要问题,尤其是在工业化的早期。从经济角度来讲,向这一群体提供服务是至关重要的,因为大部分的劳动力来自于这一群体,而劳动力是国家工业化的一个要素。从历史角度来看,向这一群体提供服务属于地方市政府的职责。因此,通过对地方政府决定的研究,可以找到与提供生活必需品政策相关的问题的最佳答案。工业化发展初期的墨西哥,是研究此类动态变化的理想之地。     

浅议中小企业的财务管理

财务管理在企业经营管理决策中起着重要的作用，分析了目前中小企业财务管理中存在的问题，从投资模式、管理控制和人员素质等3方面提出了解决这些问题的对策。     

家庭装潢中水管的选择

在室内装潢方面，人们较注重室内布局和装饰，而对给水管道则极少关注．应引起足够的重视。在建筑给水系统中由新型塑料管材替代金属管材已成为趋势。所以，室内给水管应选用新型塑料管材，并且应根据新型塑料管材的特点进行施工。确保给水系统的安装质量。     

几种石蒜属花卉观赏性状的灰色评价

以灰色关联度对14种石蒜属花卉的观赏性状进行了评价．结果表明石蒜(Lycoris radiata)的加权关联度Ri为最大(0．713 888)，即观赏效果最好，这与实际运用效果相符；其次是安徽石蒜(L．anhuiensis)，Ri=0．708 429；排在第三位的是长筒石蒜(L．longituba)，Ri=0.703032．其他由大到小次序为夏水仙(L.squamigera)、玫瑰石蒜(L．rosea)、陕西石蒜(L．shaanxiensis)、乳白石蒜(L．albiflora)、短蕊石蒜(L．caldwellii)、麦杆黄石蒜(L．straminea)、肉红石蒜(L．incornata)、中国石蒜(L．chinensis)、换锦花(L．sprengeri)、忽地笑(L．aurea)、江苏石蒜(L．houdyshelii)．从灰色关联度分析结果看，花形整齐、奇特(雄蕊长于花被片，花被片强烈皱缩反卷)，花色稀有和秋冬出叶的，灰色关联度大,14种石蒜均适合作地被，但以秋冬出叶、花葶较矮的种更为适宜，如石蒜、玫瑰石蒜、麦杆黄石蒜、江苏石蒜等。     

MERGING OPTIMALITY CONDITIONS WITH GENETIC ALGORITHM OPERATORS TO SOLVE SINGLE MACHINE TOTAL WEIGHTED TARDINESS PROBLEM

1.Introduction Production sequencing and scheduling is one of the most important activities in production planning and control.Sequencing is defined as the order in which the jobs are processed through the machines.The allocation of machines over time to process a collection of jobs is defined as Scheduling.Several methods have been developed to solve the scheduling problem which can be classified as follows:1)efficient optimal methods,2)implicit and explicit,or complete enumerative methods,a…     

无功就地补偿技术在煤矿井下的应用前景

对无功就地补偿技术在煤矿供电系统的应用中进行了分析,指出该技术能够起到节约电能、提高供电质量、节约材料费等作用,阐述了无功就地补偿技术在煤矿供电系统中的应用有较好的发展前景。