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51.
根据静电除尘振打系统的结构,建立振动模型,应用机械振动理论进行原理分析,找出相关因素。据此进行改进方案分析,并提出以改进极板自然频率为主要措施的实施方法,使静电除尘振打系统结构合理,从而延长静电除尘装置的使用寿命。  相似文献   
52.
目的探讨带蒂髂腹股沟皮瓣折叠修复手掌洞穿性缺损的围手术期护理。方法2004~2008年,12例手掌洞穿性缺损应用带蒂髂腹股沟皮瓣折叠修复,采取心理护理、皮瓣受区、皮瓣供区准备、皮瓣血运监测、皮瓣固定护理、体位护理、饮食控制等围手术期护理。结果皮瓣全部成活,康复顺利,无并发症发生。结论该围手术期系统护理策略对带蒂髂腹股沟皮瓣折叠修复方法修复手掌洞穿性缺护理是安全有效的护理方法。  相似文献   
53.
以花生仁为原料,经脱膜、油炸、调味等一系列工艺精制而成盐酥花生。结果表明:可采用干式多滚轮摩擦脱膜或湿法脱膜,最佳条件为油炸温度150~152℃,油炸时间5.5min,香盐末添加量为1.4%、香甜油添加量为1.5%。  相似文献   
54.
大型振动筛动力分析及优化设计   总被引:1,自引:0,他引:1  
郭晓玲  杨洁 《煤炭技术》2014,33(12):271-273
振动筛的强度、刚度对于其工作性能影响较大,共振现象会导致振动筛构件的断裂。介绍振动筛动力学分析理论,建立振动筛虚拟模型,计算其质量矩阵与刚度矩阵。利用有限元分析计算振动筛的应力分布,根据最大应力位置提出优化设计方案,结果显示优化方案的固有频率和最大应力都明显降低,优化效果良好。  相似文献   
55.
DHR-200 Pool Type Low Temperature Heating Reactor (DHR-200) was designed with natural circulation flap valve. In order to examine the safety of the DHR-200, the RELAP5 code was used to analyze the transient thermal-hydraulic characteristics and the natural circulation capacity under the station blackout anticipated transient without scram (SBO-ATWS). The results show that DHR-200 has enough negative temperature reactivity feedback effect. With the rising of the temperatures of the fuel and the coolant, finally the reactor can be shut down by the effect of the negative temperature reactivity feedback effect. After the accident, the natural circulation flap valve will be opened by passive means to establish a stable natural circulation, and then the residual heat of the core can be removed to pool of the reactor. Therefore, it is demonstrated that the DHR-200 has good inherent safety features.  相似文献   
56.
旋转滚筒振动筛的研制   总被引:3,自引:1,他引:2  
旋转滚筒振动筛集滚动、振动及筛转等运动于一体,筒式筛网由具有一定几何形状的特制不锈钢细筛网组成,从而提高了除砂效果。现文介绍 其结果、原理与现场试验情况,该旋转滚筒振动筛已获得国家专利(ZL93208282.3)。  相似文献   
57.
单轴椭圆型振动筛动力特性的理论分析   总被引:2,自引:1,他引:1  
单轴椭圆型振动筛是一种结构简单和使用维修方便的钻井液固控设备。常规的单轴椭圆型振动筛具有完全对称的结构,工作状况常常不能令人满意。从理论上对非对称单轴椭圆型振动筛进行了探讨,给出了非对称单轴椭圆型振动筛筛面上各点的运动轨迹、速度及加速度,并对固相颗粒在筛面上的运移机理作了分析。指出尽管非对称单轴椭圆型振动筛更有利于钻屑的排出,运动更趋合理,但在进行结构设计时,激振中心的偏离位置不能超过极限状态,否则会导致钻屑后退。  相似文献   
58.
The outermost layer of the skin, the stratum corneum, consists of non-viable keratin-filled cells, or corneocytes, embedded in a matrix of lipids. The boundary of the cells consists of cross-linked proteins with covalently bound lipids on the outer surface. The spaces between cells are filled with a mixture of ceramides, cholesterol and fatty acids. The stratum corneum provides a protective barrier against water loss through the skin and limits the penetration of potentially harmful substances from the environment. Among the covalently bound lipids on the corneocyte surface are omega-hydroxyacylsphingosine and omega-hydroxyacyl-6-hydroxysphingosine. The previously suspected presence of omega-hydroxyacylphytosphingosine is confirmed in this report through its specific isolation and characterization based on chromatographic behaviour and proton magnetic resonance spectral data.  相似文献   
59.
A comprehensive review on stratum corneum keratin organization, largely based on the recently published cubic rod-packing and membrane templating model [J. Invest. Dermatol., 123, 2004, 715], is presented. Keratin is the major non-aqueous component (wt/wt) of stratum corneum. As 90-100% of the stratum corneum water is thought to be located intracellularly one may presume that keratin also is a major factor (together with filaggrin-derived free amino acids) determining stratum corneum hydration level and water holding capacity. This water holding capacity depends in turn on the structural organization of the corneocyte keratin intermediate filament network. The cubic rod-packing model for the structure and function of the stratum corneum cell matrix postulates that corneocyte keratin filaments are arranged according to a cubic-like rod-packing symmetry. It is in accordance with the cryo-electron density pattern of the native corneocyte keratin matrix and could account for the swelling behaviour and the mechanical properties of mammalian stratum corneum. The membrane templating model for keratin dynamics and for the formation of the stratum corneum cell matrix postulates the presence in viable epidermal cellular space of a highly dynamic small lattice parameter (<30 nm) membrane structure with cubic-like symmetry, to which keratin is associated. It further proposes that membrane templating, rather than spontaneous self-assembly, is responsible for keratin intermediate filament formation and dynamics. It is in accordance with the cryo-electron density patterns of the native keratinocyte cytoplasmic space and could account for the characteristic features of the keratin network formation process, the dynamic properties of keratin intermediate filaments, the close lipid association of keratin, the insolubility in non-denaturating buffers and pronounced polymorphism of keratin assembled in vitro, and the measured reduction in cell-volume and hydration level between stratum granulosum and stratum corneum.  相似文献   
60.
Iris L. is one of the important genus of family Iridaceae, consist of 56 taxa naturally occurred in Turkey. The similarities and variations in the subgenus overlapping the taxonomic positions of the species in the subgenera and needs anatomical assessment especially by microscopic techniques. In this study, the taxonomic significance of leaf anatomical characters of 10 Iris subgenus Scorpiris taxa were studied in detail and the relationship among these taxa were evaluated using microscopy techniques. Fresh leaf samples of species were fixed in 70% alcohol solution for anatomical observation under microscope. Eleven different micromorphological features were statistically analyzed to delimit the species in subgenus. Based on morphological and anatomical similarities, we studied relationships among; (1) ssp. turcica, ssp. caucasica, I. nezahatiae and I. pseudocaucasica; (2) correlation between ssp. turcica and ssp. caucasica; (3) association of I. galatica, I. persica, ssp. margaretiae and ssp. stenophylla with each other; (4) relationship between ssp. stenophylla and ssp. margaretiae; and (5) relevance between I. aucheri and I. peshmeniana. Moreover, the taxonomy of subgenus Scorpiris has been discussed in detail with novel and diagnostic features based on micromorphological physiognomies. We found that four species in this study are endemic to Turkey, while seven are critically endangered geophytes in the country. The leaf anatomical characteristics of 10 taxa were divided into three groups. Main aim of this research was to study the taxonomy of the complex subgenus Scorpiris through microscopic techniques.  相似文献   
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