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1.
Rationalizing drawings for chemical apparatus . For small and medium-sized manufacturers of apparatus, producing drawings may constitute a disproportionate waste of time and personnel, particularly when no new designs are involved but only modification or improvement of drawings supplied by the customer. One possibility for rationalizing drawing is to simplify the old-fashioned approach by using symbols for frequently drawn or standard items, or by listing alphanumerically. This presumes a kind of systematization permitting determination of those symbols and their reasonable use, as well facilitating rationalization by means of data processing. There are different approaches to computer-aided drawing (from computer controlled drawing-board to interactive screens); here a CAD programme is presented which was especially developed for graphic presentation of chemical apparatus, and which can be used without learning a programming language.  相似文献   
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兰蓉 《微机发展》1996,6(3):27-29
在分析用电话线及MODEM进行PC机点-点远程通信和利用局城网LAN进行PC机通信的优缺点后,本文介绍用通信服务器进行PC机远程通信的方法.  相似文献   
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Melanoma is the deadliest form of skin cancer and accounts for about three quarters of all skin cancer deaths. Especially at an advanced stage, its treatment is challenging, and survival rates are very low. In previous studies, we showed that the constituents of the roots of Onosma paniculata as well as a synthetic derivative of the most active constituent showed promising results in metastatic melanoma cell lines. In the current study, we address the question whether we can generate further derivatives with optimized activity by synthesis. Therefore, we prepared 31, mainly novel shikonin derivatives and screened them in different melanoma cell lines (WM9, WM164, and MUG-Mel2 cells) using the XTT viability assay. We identified (R)-1-(1,4-dihydro-5,8-dihydroxy-1,4-dioxonaphthalen-2-yl)-4-methylpent-3-enyl 2-cyclopropyl-2-oxoacetate as a novel derivative with even higher activity. Furthermore, pharmacological investigations including the ApoToxGloTM Triplex assay, LDH assay, and cell cycle measurements revealed that this compound induced apoptosis and reduced cells in the G1 phase accompanied by an increase of cells in the G2/M phase. Moreover, it showed hardly any effects on the cell membrane integrity. However, it also exhibited cytotoxicity against non-tumorigenic cells. Nevertheless, in summary, we could show that shikonin derivatives might be promising drug leads in the treatment of melanoma.  相似文献   
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We aimed to assess the in vitro antimicrobial activity and the in vivo effect on the murine fecal microbiome and volatile organic compound (VOC) profile of (S)-reutericyclin. The antimicrobial activity of (S)-reutericyclin was tested against Clostridium difficile, Listeria monocytogenes, Escherichia coli, Enterococcus faecium, Staphylococcus aureus, Staphylococcus (S.) epidermidis, Streptococcus agalactiae, Pseudomonas aeruginosa and Propionibacterium acnes. Reutericyclin or water were gavage fed to male BALBc mice for 7 weeks. Thereafter stool samples underwent 16S based microbiome analysis and VOC analysis by gas chromatography mass spectrometry (GC-MS). (S)-reutericyclin inhibited growth of S. epidermidis only. Oral (S)-reutericyclin treatment caused a trend towards reduced alpha diversity. Beta diversity was significantly influenced by reutericyclin. Linear discriminant analysis Effect Size (LEfSe) analysis showed an increase of Streptococcus and Muribaculum as well as a decrease of butyrate producing Ruminoclostridium, Roseburia and Eubacterium in the reutericyclin group. VOC analysis revealed significant increases of pentane and heptane and decreases of 2,3-butanedione and 2-heptanone in reutericyclin animals. The antimicrobial activity of (S)-reutericyclin differs from reports of (R)-reutericyclin with inhibitory effects on a multitude of Gram-positive bacteria reported in the literature. In vivo (S)-reutericyclin treatment led to a microbiome shift towards dysbiosis and distinct alterations of the fecal VOC profile.  相似文献   
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通过对陶瓷墙地砖的坯釉原料、化学成份、生产工艺流程和产品的铅溶出量检测逐一分析研究,从理论和实践的结合上探讨了陶瓷墙地砖铅溶出量的问题。  相似文献   
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藏文字频统计是藏文信息处理的基础性工作,通过对藏文字的部件、音节、结构和字的频度与通用度等定量统计与定性分析,为藏文信息处理提供基础数据。藏文字是一种由藏文字构件横向和纵向组合而成的拼音文字,在藏文字频统计中不仅要从整字角度统计分析藏文字频度属性,还要统计分析构成其构件的频度及位置属性。因此,在藏文字频统计系统中要分解构成藏文字的各部件。本文通过开发藏文字频统计系统,利用组合构件库结合藏文文法提出了一种藏文字构件分解算法。经测试,该算法不仅简单易行,而且可以有效地确定出各基本构件的位置特征,已应用于项目藏文字频统计系统。  相似文献   
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Today technology design can no longer be understood as a design process on a green site. Design and implementation of new technology are always dependent on existing technology and the way it is used by people. In this respect Software-Engineering has also changed to the characteristics of normal technology design taking into account existing computer systems. Experiences show that the conditions and needs of such Software-Reengineering projects are highly complex and differ in their special characteristics ranging from aspects of quality of existing system documentation to organizational structures of the computer departments concerned. The Task-Artifact Cycle presented here gives a suitable reengineering approach emphasizing both analysis and design in Software-Reengineering.  相似文献   
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针对单通道音增强,常用的谱减法及其改进型算法等语音增强方法不能很好地消除残留音乐噪声以及不能兼顾噪声抑制和语音失真的问题,提出用维纳滤波法与掩蔽效应相结合的算法。介绍了DSP的实现方法。结果表明,该算法相对于传统谱减法和改进谱减法语音增强效果显著、失真小、音乐噪声几乎没有,并且本算法计算量小,很容易在基于DSP的语音增强算法中实现。  相似文献   
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