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通过对大气细菌数量、霉菌数量与风速相关性的研究,得出齐市地区冬季气候寒冷,无相关性;春季气候干燥,风沙大,有相关性;雨后大气细菌数量与风速无相关性,大气霉菌数量与风速相关。  相似文献   
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安全帽作为对自然人头部受坠落物体或其他特定因素引起的伤害所采用的个人防护用品,越来越受到世界各国的安全防护行业的重视。特别是在发达国家,不断进行技术创新,更新安全帽标准。本文从安全帽技术领域方面.详细介绍各国制造安全帽常用材料的性能与特点,安全帽的模具材料、加工工艺、先进生产技术以及主要国家的安全帽检测标准差异。  相似文献   
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霉菌TM-3的成球条件及其对染料的吸附脱色研究   总被引:1,自引:0,他引:1  
通过对霉菌TM-3培养条件的研究,考查了培养条件对霉菌菌丝球产量、菌球特征及菌球吸附脱色性能的影响。实验结果表明:该霉菌在以蔗糖为碳源,乙酸胺为氮源时,250mL三角瓶装液量为100~125mL,1%接种量(孢子悬液浓度10^4),pH6,34℃,150r/min摇床培养60-72h时,可形成直径在1.O~2.5mm范围内的菌丝球,生物量可达150~200g/L(重)。球体白色光滑均匀,具有一定的机械强度,对10mg/L的酸性大红和200mg/L的刚果红吸附脱色达80%以上。培养条件的改变对菌球的特征、产量影响较大,对菌球吸附性能的影响相对较小。  相似文献   
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阐述了双排10工位接插件级进模的设计方法.主要探讨了级进模工步设计和CAD.  相似文献   
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高精度模具加工除了与机床本身精度有关外电火花电源起重要作用。电极损耗性能与生产率、粗糙度等性能相比更起关键作用。此文论述了在保证同样的电极损耗下,性能优良的电极损耗将使粗糙度更细、放电间隙更小、生产率更高。在例举若干较高的电极损耗指标后提出了评审某电源的电极损耗性能高低的标准。  相似文献   
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叙述了薄板弯曲成“U”型所采用可调辊轧式模具的实际情况,介绍了应用各种不同材料后如何控制回弹的方法.  相似文献   
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We report on the prenatal diagnosis and ultrasonographic findings of a second-trimester fetus with jumping translocation involving chromosome 22. A 28-year-old gravida 2, partus 1, Turkish woman was referred for genetic counselling and ultrasonographic examination at 18 weeks' gestation because of a high risk of trisomy 21 in triple test. Prenatal ultrasonography showed tetralogy of Fallot with a diverticular dilatation of the pulmonary artery, flattened brow, complete absence of the right upper limb, hypospadias, oligodactyly (three digits) in left hand and in both feet, and hyperechogenic abdominal foci. Amniocentesis revealed a karyotype of 46,XY[4]/46,XY,−8,+ der(8),t(8;22)(q24.3;q11.21)[2]/45, XY,−22,−8,+ der(8)t(8;22)(q24.3;q11.21)[22]/45,XY,−22,−5,+ der(5)t(5;22)(q35.3;q11.21)[44]. A C-banding and FISH study with a specific centromeric probe (D14Z1/D22Z1) for chromosome 22 was made. In our case, partial monosomy for the regions 22q11.21→22pter, 8q24.3→8qter and 5q35.3→5qter may partially explain the fetal malformations. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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此文对T10钢经线切割加工的开裂模具进行了金相分析、应力分析和断裂分析,从而提出了减少变形和开裂的措施。列举了生产实例,供模具制造者参考。  相似文献   
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In experiments that comprised of three phases (fight, choice, and mating) under “seen” and “unseen” conditions, we examined the effects of the outcomes of male–male contests and female eavesdropping on female mate choice and male mating success in the fighting spider, Thiania bhamoensis (Salticidae). The results revealed female eavesdropping on agonistic interactions. Females that had watched an aggressive interaction showed no distinctive preference for the winner over the loser, but they preferred the loser when they had not observed a fight. Winners, however, achieved a greater mating success than did losers during the mating phase. Gaining access to females was based on the insistence of the winners in courtship in terms of the number of quivers, rather than on the fighting behavior of the males. Hence, the outcome of male–male contests may not be an important determinant of a male’s mating success in T. bhamoensis. Instead, courtship display plays an important role in determining the success of male mating in this species. This study also suggests that female mate preference may not be a good indicator of eventual female mate choice and male mating success. Thus, a causal relationship between female mate preference and male mating success cannot be inferred. Joanna P. Y. Chan, Pei Rong Lau, and Ai Jie Tham contributed equally.  相似文献   
10.
此文提出了一种基于先进制造技术、并行工程、知识工程及网络技术于一体的虚拟仿真系统思想——VS,对其组织方式、结构模型、环境关键技术和发展前景作了尝试性地探讨研究。这将有助于整个模具制造业找到一个新的应用发展突破点,真正体现高速、高效、高质的优势。  相似文献   
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