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在普通圆纬机上编织彩横条织物时,彩横务循环单元受到一定限制。而在具有四色或六色调线装置的横务纹机上编织彩横条织物时,可扩大彩横条循环单元的横列数。文中举列说明了彩横条织物的设计与上机工艺的制定方法。  相似文献   
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磁钢的居里等温面,是钢加热时从铁磁性状态向顺磁性状态转变、冷却时则反之的第二级相变面。磁钢感应加热时,居里等温面磁导率的急剧变化及其空间位置的改变将导致感应电流密度和释热源的空间再分布,在一定条件下,这将引起居里相变面不稳定,会随着时间和空间产生波动,断开成独立的区段。  相似文献   
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The authors studied the striped mouse (Rhabdomys pumilio) in the semiarid succulent karoo of South Africa. Mice forage alone, but they live in groups that share a common nest. Groups consist of 1 to 4 breeding females, 1 to 2 breeding males, and their offspring of both sexes, which remain in their natal group even after reaching adulthood, participating in territorial defense and nest building without showing signs of reproductive activity. Interactions are typically amicable and take place inside or in front of the nest. In contrast, encounters with mice from other groups are aggressive. Group living in the succulent karoo is possibly due to ecological constraints imposed by habitat saturation because of a year-round stable food supply as well as associated benefits of philopatry. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This study determined quality changes of whole ungutted golden gray mullet (Liza aurata) while stored in ice or in a refrigerator (without ice). Changes in microbiological quality (total viable and psychrophilic counts, lactic acid bacteria and Enterobacteriaceae), chemical quality (pH, total volatile basic nitrogen, trimethylamine, peroxide value, thiobarbituric acid, and free fatty acids), and raw fish sensory attributes were evaluated during 16 days of storage. The sensory attributes of golden gray mullet correlated well with the microbiological analyses (r = 0.92). Based on the overall raw acceptability sensory scores and the microbiological tests, the shelf life of the raw golden gray mullet was 10 days in ice and about 14 days in a refrigerator.  相似文献   
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It has been under debate if a self‐assembled monolayer (SAM) with two immiscible ligands of different chain lengths and/or bulkiness can form a stripe‐like pattern on a nanoparticle (NP) surface. The entropic gain upon such pattern formation due to difference in chain lengths and/or bulkiness has been proposed as the driving force in literature. Using atomistic discrete molecular dynamics simulations it is shown that stripe‐like pattern could indeed emerge, but only for a subset of binary SAM systems. In addition to entropic contributions, the formation of a striped pattern also strongly depends upon interligand interactions governed by the physicochemical properties of the ligand constituents. Due to the interplay between entropy and enthalpy, a binary SAM system can be categorized into three different types depending on whether and under what condition a striped pattern can emerge. The results help clarify the ongoing debate and our proposed principle can aid in the engineering of novel binary SAMs on a NP surface.  相似文献   
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Determination of trace element levels (arsenic, As; cadmium, Cd; cobalt, Co; chromium, Cr; copper, Cu; iron, Fe; lead, Pb; manganese, Mn; nickel, Ni; selenium, Se; and zinc, Zn) in the edible part (muscle) of golden gray mullet (Liza aurata: Mugilidae) and the potential health risk from consuming this fish were assessed. Sixty fish were caught by beach seine along the south-central shoreline of the Caspian Sea (Mazandaran province). Concentrations of trace elements were determined by ICP-AES. The mean concentration of As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Se, and Zn in the muscle of golden gray mullet were 1.39, 0.036, 0.260, 0.514, 1.87, 5.66, 1.29, 0.181, 0.971, 2.01 and 7.41 mg kg?1 wet weight, respectively. Although the higher concentrations of Cr and Cu were recorded in this study in comparison to previous studies, maximum levels of trace elements, except for As and Ni, were lower than the international standards proposed by the World Health Organization (WHO), the Ministry of Agriculture, Fisheries, and Food of the United Kingdom (MAFF), and the United States Environmental Protection Agency (USEPA). Daily intakes of these trace elements through fish consumption were compared with the established values. The hazard quotients calculated for all trace elements showed that the examined fish are considered safe for human consumption.  相似文献   
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阐述与输入物面密贴的位相型光学元件;条形散斑屏,随机相移器和位相光栅在光学全息及信息处理中的重要应用。分析了三类元件在应用和制作 中的共性问题及各自特点;针对这类银盐板遇光后黑化失效的弊病提出了避免的方法与工艺之改进。  相似文献   
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网状及条带式加筋拉拔特性的试验研究   总被引:1,自引:0,他引:1  
在试验的基础上,分析了网状加筋与填土的相互作用机理及其抗拔力的组成,并按筋网与土体之间相对位移的大小,将抗拔过程划分为初始阶段、发展阶段和破坏阶段;得出了网状加筋抗拔力比条带式加筋抗拔力大得多的结论;提出了网状加筋抗拔力的计算公式,对条带式加筋进行抗拔力计算时,应考虑水平和垂直两个方向的“群筋效应系数”,加筋土支挡结构的抗拔力计算,宜采用拉拔似摩擦系数.  相似文献   
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