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101.
本文离殷钢荫罩彩色显像管拚接式双金属弹簧片的设计及试验,确定了该管型的整管结构设计。  相似文献   
102.
With advances in Si-based technology infrastructures and the rapid integration of Si-based op-toelectronics,Si-based optoelectronic synaptic devices have the po...  相似文献   
103.
染色过程中取得深色效果的几种途径   总被引:1,自引:0,他引:1  
文章针对纺织品深浓色染色较为困难的实际情况,从分析深色效果的基本理论着手,对染色中常用的提高织物上染率手段进行比较分析,并对几种取得深浓色效果的主要途径作出综述。  相似文献   
104.
一种基于软阈值方法的改进A1/A2极化干涉分类算法   总被引:3,自引:0,他引:3  
在分析了极化干涉技术的发展现状和发展趋势的基础上,从极化干涉的特殊性入手,分析了干涉相干系数在极化干涉分类中的作用,并且系统分析了基于相干最优优化后的相干系数进行极化干涉分类过程的原理,总结了现有极化干涉分类算法在阈值选择方面存在的不足,阐述了硬阈值方法和软阈值方法的基本原理和它们之间的区别,最后提出基于软阈值方法的改进A1/A2非监督极化干涉分类算法,解决了极化干涉分类现有的分类空间中的阈值问题。实验表明这种方法能够得到更好的分类结果,做出了改进。  相似文献   
105.
Vibrio vulnificus is a gram-negative bacterium that naturally occurs in estuarine waters and marine environment. Consumption of seafood contaminated with V. vulnificus or exposure to the contaminated water causes septicemia, gastroenteritis or wound infections in humans. This study aimed at identifying the prevalence of V. vulnificus in shrimps in Chinese seafood market. From June to September 2009, 239 samples encompassing six shrimp species were collected from ten cities in China. To quantify the prevalence and the levels of V. vulnificus in shrimps, the most probable number (MPN) method was used combining with the polymerase chain reaction (PCR) which was used to classify the isolates by detecting V. vulnificus hemolysin gene (vvhA). One hundred and forty out of 239 samples were positive for V. vulnificus, with the geometric mean level at 153.3 MPN/g. The prevalence and levels of V. vulnificus in shrimps varied in different geographic areas, with the values for the samples in the South cities (179.6 MPN/g) remarkably higher than that in the North cities (7.6 MPN/g). In addition, we found that 61.7% (79/128) of the V. vulnificus positive samples contained C-type (Clinical) strains and 8 contained E-type (Environmental) strains. The antimicrobial susceptibility of the isolates to 12 antibiotics was tested as well. Most of the 169 isolates remained susceptible to the majority of antimicrobials tested, whereas some strains tend to be less sensitive to amikacin, ampicillin, tetracycline and gentamicin. In conclusion, V. vulnificus is commonly found in retail marine shrimp in Chinese seafood market, and most of the shrimp samples contained C-type strains, which may pose a potential threat to human health.  相似文献   
106.
The response of Cu–40%Zn alloy to wear during unidirectional and bidirectional abrasion processes was investigated. It was observed that the mass loss of the alloy decreased as the number of times of changing the sliding direction was increased. Corresponding to this decrease in mass loss, hardness of the worn surface increased initially and then decreased. Cracking in the surface layer was analyzed to get an insight into the mechanism involved. Results of the study suggest that Baushinger’s effect played a role when the sliding direction was alternated.  相似文献   
107.
Previously, we demonstrated a decrease in wear loss of Cu-40%Zn against a steel wheel during bidirectional sliding ascribed to Bauschinger’s effect associated with diminished strain-hardening. However, the situation changed when the alloy was worn by a ceramic-grinding wheel. It was observed that the mass loss continuously increased with reversal of the sliding-direction although the corresponding hardness of worn surface also decreased. In this case, Bauschinger effect still functioned but the failure mode varied, leading to the different trend of response to wear against the ceramic-grinding wheel in comparison with that against the steel counter-face.  相似文献   
108.
109.
强直性脊柱炎是一种原因不明,以中轴关节慢性炎症为主的全身性疾病,主要累及骶髂关节、髋关节、椎间关节、肋椎关节、以骶髂关节病变最为多见.其主要病理改变是关节和关节周围组织、韧带、椎间的韧带钙化,最终发生骨性强直.强直性脊柱炎多见于青年男性,发病年龄多在15-35岁.40岁以后发病者少见,男性患病是女性的5倍.一项研究对我国6000名风湿病患者调查统计,强直性脊柱炎患者占18%,一般人群的调查发病率0.3%,即1000人中有一位患病,全国将近12万人患此病,这一数据表明该病对家庭和社会是一个沉重负担.  相似文献   
110.
It has been found difficult to fully densify some mechanically milled pure metal powders by spark plasma sintering (SPS). In this study, the densification behavior of cryomilled, nanostructured (NS) Cu powders during SPS was related to changes to the chemistry of the powders. The results showed that the presence of very small amounts of O and N in the powders, which were introduced during cryomilling and handling, significantly influenced the densification response. Moreover, reduction/removal of O/N via thermal annealing of the powders before SPS led to complete densification of the powders during subsequent SPS. The mechanisms responsible for this behavior were ascertained: O and N existed in the cryomilled powders in the form of thermally unstable compounds, and the subsequent thermal decomposition of these compounds during SPS generated the gaseous species, leading to porosity formation and incomplete densification; annealing of the powders before SPS removed the gases which resulted from thermal decomposition, thereby facilitating complete consolidation during subsequent SPS.  相似文献   
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