高强高模聚乙烯纤维的技术进展及应用

介绍了高强高模聚乙烯(HSHMPE)纤维的国内外生产概况、研发现状、应用领域及市场前景;对国内HSHMPE纤维产业的今后发展提出了建议。即国内科研单位和企业对照国外标准找差距,完善提升HS-HMPE纤维生产技术路线;整合国内市场,制定HSHMPE纤维国内标准,形成规模化。     

Formation of conductive polyaniline nanoarrays from block copolymer template via electroplating

Nanostructured thin films have drawn extensive attention because of their unique properties resulting from nanoscale features. One of the convenient ways to generate nanostructured thin films is to use pattern with nanoscale texture as a template for the reactions carrying out within the template. In this study, nanoporous thin film template was obtained from the self-assembly of degradable block copolymer, polystyrene-b-poly(l-lactide) (PS-PLLA) with PLLA cylinder nanostructure, at which the PLLA block can be hydrolyzed to form the nanopatterns with cylinder nanopores on conductive substrate (i.e., ITO substrate). The nanoporous PS thin film template was stabilized by modification of substrate using hydroxyl terminated PS so as to enhance the adhesion with substrate for following electroplating process. Combining a pulse electroplating method with the control of micro current, polyanilines can be successfully synthesized within the template to fabricate well-defined of conductive polymer nanoarrays.     

可控震源DGPS技术的使用

DGPS技术在可控震源上的应用，对提高可控震源的野外生产效率、保障设备的安全、减轻劳动强度等方面都能起到积极的作用。本文介绍了可控震源应用DGPS技术后，在野外施工过程中如何在保证采集资料质量的前提下，有效地提高施工效率。     

山特维克集团近年发展动态

介绍瑞典山特维克集团结构及其三大领域近年经营概况 ,分析 1999年山特维克市场状况 ,报道集团在世界不同地区的市场销售情况     

The effects of VDT data entry work on operators

The before/after study of physiological and biochemical parameters was used to delineate the effects of VDT data entry work on operators. Twenty-nine healthy Chinese students were chosen and divided at random into the simple and the complicated data entry group. The subjects were instructed to work as quickly and correctly as possible according to the 'Data Entry Work Programme' for 150 min. Work performance (correct entry) was automatically recorded once every 10 min. The before/after parameters were tested respectively. The results showed that performance fluctuated over time. It decreased obviously after 50-60 min of work, followed by a rebound, and there was a terminal motivation phenomenon at the end of the test, which was associated with the auto-arousal and cerebral compensatory effort. Changes in physiological parameters revealed that operators were fatigued after data entry work. The adrenaline excretion in urine showed a tendency to increase after simple data entry work. The noradrenaline excretion showed a tendency to decrease after complicated data entry work. The differences in performance, diastolic blood pressure in a standing position and neurobehaviour between two groups indicated that much stress was experienced when performing complicated data entry work.     

Interface crack between two elastic layers

A semi-infinite interface crack between two infinite isotropic elastic layers under general edge loading conditions is considered. The problem can be solved analytically except for a single real scalar independent of loading, which is then extracted from the numerical solution for one particular loading combination. Two applications of the basic solution are made which illustrate its utility: interface cracking driven by residual stress in a thin film on a substrate, and an analysis of a test specimen proposed recently for measuring interface toughness.

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Résumé On considère une fissure d'interface semi-infinie entre deux couches infinies élastiques et isotropes soumises à des conditions générales de sollicitations sur leurs bords. Le problème peut être solutionné par voie analytique, à l'exception d'un scalaire réel simple, indépendant de la charge, qui est extrait de la solution numérique relative à une combinaison particulière des sollicitations.On procède à deux applications de la solution de base qui illustrent son utilité: l'une est relative à une fissure d'interface soumise aux tensions résiduelles dans un film mince déposé sur un substrat. L'autre est l'analyse d'une éprouvette d'essai proposée récemment pour mesurer la ténacité de l'interface.

     

Amide II and Amide III Bands in Polyurethane Model Soft and Hard Segments

Summary Amide II and III bands in polyurethane (PU) have been often taken as two of the characteristic bands indicating the formation of urethane structure. Since these bands, however, are very complicated, further studies, especially the effect of H-bonds on amide II and III bands in PU, were seldom reported. In the present work, we report a new finding on the correlation of amide II and amide III bands with different H-bonding interactions in PU model soft and hard segments. The PU model soft segment (PUMSS) is based on poly(tetrahydrofuran) (PTHF) and diphenylmethane-4,4’-diisocyanate (MDI) whereas the PU model hard segment (PUMHS) is based on MDI and n-butanol (BO). FTIR results show that the H-bond is formed by NH...carbonyl (C=O) (Type I) in PUMHS while the H-bond is mainly formed by NH...ether(O) (Type II) in PUMSS; the amide II band, however, is more related to the Type II H-bonding interaction while amide III band is more dependent upon the Type I H-bonding interaction.     

激光焊金刚石圆锯片的无损检测

本文旨在探求激光焊锯片焊接质量的一种新型测量方法－超声波测量法。这种方法的主要原理是运用超声波的反射特性来对激光焊锯片区进行厚度测量，从而评估出激光焊锯片的焊接质量。这种测量方法的主要优点在于测量的非破坏性。     

稳定的参数自适应控制系统及其应用

本文讨论了动态系统的自适应控制问题,依据系统的随机非明确部分的参数随机化补偿方法,设计了一种保证系统稳定的参数自适应控制策略。应用这种策略对纸张生产过程中的定量、水份双变量闭环控制,收到了较好的效果。     

VE432系统与电台中继站配套施工探讨

VE432系统与电台中继站配套施工可以弥补电台通讯遇到盲区没有信号的不足.本文着重介绍通过几项试验和测试,证实可控震源VE432控制系统与电台中继站配套放炮的可行性,以及VE432控制系统在使用中继站后带来的风险和风险防范措施.