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991.
本文从重庆、沈阳、上海三地分别抽取库存一年、两年、三年的羽绒服,根据GB/T 14272《羽绒服装》进行微生物检测,探讨各地环境、库存时间对羽绒服微生物的影响,为企业改善羽绒制品的仓储条件提供依据。 相似文献
992.
《Ergonomics》2012,55(11):1088-1100
This article reports on two numerical studies on the microclimate around, and the thermal neutrality of, a sleeping person in a space installed with a displacement ventilation system. The development of a sleeping computational thermal manikin (SCTM) placed in a space air-conditioned by a displacement ventilation system is first described. This is followed by reporting the results of the first numerical study on the microclimate around the SCTM, including air temperature and velocity distributions and the heat transfer characteristics. Then the outcomes of the other numerical study on the thermal neutrality of a sleeping person are presented, including the thermal neutrality for a naked sleeping person and the effects of the total insulation value of a bedding system on the thermal neutrality of a sleeping person. Statement of relevance: The thermal environment would greatly affect the sleep quality of human beings. Through developing a SCTM, the microclimate around a sleeping person has been numerically studied. The thermal neutral environment may then be predicted and contributions to improved sleep quality may be made. 相似文献
993.
《Intermetallics》2014
The electronic structure and chemical bonding properties of four families of Ce2T2X (T = nd element; X = Mg, Cd, Pb or Sn) intermetallics crystallizing in an ordered U3Si2 type structure are shown from density functional theory (DFT) calculations to present electronic and magnetic structure properties arising from their peculiar valence electron count (VEC). Trends of the magnetism are discussed in terms of the characteristics of the Ce(4f) states as well as the energetic position of the transition metal element d states. 相似文献
994.
C. A. Mullen T. J. Vaughan M. C. Voisin M. A. Brennan P. Layrolle L. M. McNamara 《Journal of the Royal Society Interface》2014,11(101)
Extracellular mechanical cues have been shown to have a profound effect on osteogenic cell behaviour. However, it is not known precisely how these cues alter intracellular mechanics to initiate changes in cell behaviour. In this study, a combination of in vitro culture of MC3T3-E1 cells and finite-element modelling was used to investigate the effects of passive differences in substrate stiffness on intracellular mechanics. Cells on collagen-based substrates were classified based on the presence of cell processes and the dimensions of various cellular features were quantified. Focal adhesion (FA) density was quantified from immunohistochemical staining, while cell and substrate stiffnesses were measured using a live-cell atomic force microscope. Computational models of cell morphologies were developed using an applied contraction of the cell body to simulate active cell contraction. The results showed that FA density is directly related to cell morphology, while the effect of substrate stiffness on internal cell tension was modulated by both cell morphology and FA density, as investigated by varying the number of adhesion sites present in each morphological model. We propose that the cells desire to achieve a homeostatic stress state may play a role in osteogenic cell differentiation in response to extracellular mechanical cues. 相似文献
995.
Michal Apollo 《The International journal of environmental studies》2017,74(1):129-158
Each year, millions of mountaineers visit high-mountain areas. They generate tonnes of faeces and cubic hectometres of urine annually. Thus, proper disposal of human waste is important for the conservation and appropriate management of high-mountain areas. The management can address the issue in three ways: the good (complete/non-invasive); the bad (partial/superficial); and the ugly (invasive). With use of those categories, 20 selected summits from different parts of the world have been evaluated, separately in respect to faeces and urine. It was expected that correct or incorrect disposal of human waste would depend on the changing altitude and/or development level. Disappointingly, the correlation between selection criteria (better or worse solution) and the increase of altitude does not exist. Similarly, the increase of the development level does not play a significant role, especially when urine is taken under consideration. The problem is more global than was thought. The paper makes recommendations which could lead to reduction of this problem. 相似文献
996.
在分析海水入侵形成机理的基础上,从特殊地质环境及相关自然因素和人类工程经济活动两大方面分析了深圳市海水侵入的原因,启示我们在大力发展经济建设时,应统筹考虑对人类生存的自然环境的保护,不能以牺牲生态环境来换取经济效益。 相似文献
997.
基于高精度的野外地表控制网,针对不同的时间、地点和温度变化环境以及振动变化环境等实际的野外观测条件,对HGG05型陀螺全站仪的稳定性和指北定向精度进行测试与研究,通过多个周期测试数据的分析,总结出了一套方法可行、成果可靠的陀螺全站仪测试方法与数据处理程序。 相似文献
998.
Antonella Ilenia Alfano Prof. Elisabetta Buommino Prof. Maria Grazia Ferraro Prof. Carlo Irace Prof. Angela Zampella Prof. Heiko Lange Prof. Margherita Brindisi 《ChemMedChem》2021,16(24):3795-3809
The generation of peptidomimetic substructures for medicinal chemistry purposes requires effective and divergent synthetic methods. We present in this work an efficient flow process that allows quick modulation of reagents for Joullié-Ugi multicomponent reaction, using spiroindolenines as core motifs. This sterically hindered imine equivalent could successfully be diversified using various isocyanides and amino acids in generally good space-time yields. A telescoped flow process combining interrupted Fischer reaction for spiroindolenine synthesis and subsequent Joullié-Ugi-type modification resulted in product formation in very good overall yield in less than 2 hours compared to 48 hours required in batch mode. The developed protocol can be seen as a general tool for rapid and facile generation of peptidomimetic compounds. We also showcase preliminary biological assessments for the prepared compounds. 相似文献
999.
噢易机房BOSS系统提供Dos和Windows双模式操作,教学可能需要很多个不同类的操作系统,不同的系统里面安装不同的教学软件,安装第一个系统的时候从这个系统中创建多个频道,频道和真实的系统完全一样。这样的话可以减少磁盘的使用空间,方便维护与管理,可快速搭建个人私密的开放系统环境,方便学生在机房保存学习资料、完成作业或进行课程设计、毕业设计等任务。 相似文献
1000.
为了更好地认识和了解CL-20晶体结构演变规律和相变行为,利用金刚石对顶砧超高压实验技术,在0~50GPa下,研究了高压下ε-CL-20的原位拉曼光谱和红外光谱。结果表明,CL-20晶体在整个加压过程中存在两个相变,第一个相变发生在4.2~7.5GPa,认为是ε相到对称性更低的γ相转变,相变产生的原因是在压强的作用下,笼环外的硝基方向发生改变,电子云密度重置导致的分子构型转变;第二个相变发生在14.2~18.9GPa,属于γ相到ζ相的晶体结构转变;卸压后,拉曼和红外光谱恢复常压状态,表明CL-20晶体在研究压强范围内的相变过程是可逆的。 相似文献