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941.
942.
介绍了履带式蜘蛛型高空作业平台的基本结构,分析整机工作时底架结构最不利工况。对底架结构中的重要部件进行有限元分析,通过分析上车载荷作用在底架正前和正侧方工况,得到底架部件结构应力及位移图云图。  相似文献   
943.
944.
In this study, 13 polymorphic microsatellite markers were isolated from the Phaseolus vulgaris L. (common bean) by using the Fast Isolation by AFLP of Sequence COntaining Repeats (FIASCO) protocol. These markers revealed two to seven alleles, with an average of 3.64 alleles per locus. The polymorphic information content (PIC) values ranged from 0.055 to 0.721 over 13 loci, with a mean value of 0.492, and 7 loci having PIC greater than 0.5. The expected heterozygosity (HE) and observed heterozygosity (HO) levels ranged from 0.057 to 0.814 and from 0.026 to 0.531, respectively. Cross-species amplification of the 13 prime pairs was performed in its related specie of Vigna unguiculata L. Seven out of all these markers showed cross-species transferability. These markers will be useful for future genetic diversity and population genetics studies for this agricultural specie and its related species.  相似文献   
945.
Earth-abundant iron pyrite (FeS2) shows great potential as a light absorber for solar cells and photodetectors due to their high absorption coefficient (>105 cm-1). In this paper, high-quality phase-pure and single crystalline pyrite nanocrystals were synthesized via facile, low-cost, and environment friendly hydrothermal method. The molar ratio of sulphur to iron and the reaction time play a crucial role in determining the quality and morphology of FeS2 nanocrystals. X-ray diffraction and high-resolution transmission electron microscopy confirm that phase-pure and single crystalline pyrite nanocrystals can be synthesized with high sulphur to iron molar ratio and sufficient reaction time. For the first time, a crystalline nanogap pyrite photodetector with promising photocurrent and UV-visible photoresponse has been fabricated. This work further demonstrates a facile route to synthesize high-quality FeS2 nanomaterials and their potential in optoelectronic applications.  相似文献   
946.
国标法中高锰酸盐指数的测定是一个条件性指标,各操作环节都将影响其测定结果的准确性。本文通过调研大量文献资料,对酸性高锰酸盐指数测定的影响因素进行了总结,希望对相关工作人员的监测工作带来帮助。  相似文献   
947.
This paper provides a framework that integrates and reinterprets prior research on satisfaction modeling (function) and proposes the existence of non-linear and curvilinear/higher-order relationships to model online banking customers. It provides a framework that examines two closely related but distinct countries—Malaysia, a developing country, and Singapore, a developed country—and identifies whether modeling online banking customers through satisfaction is unique to each context or is generic. Using a systematic and step-by-step hierarchical moderated regression approach, this study tries to understand the relationship among repurchase intention, satisfaction, and trust, moderated by bank size. Malaysia portrays a linear relationship, while Singapore depicts non-linear and curvilinear/high-order relationships. The findings suggest that modeling online banking customers through satisfaction depends on a country’s economic development. By contrast, prior studies on modeling customers through satisfaction were conducted independently and did not employ proper and systematic steps to capture the satisfaction function.  相似文献   
948.
949.
We theoretically investigate the spontaneous emission light of an excited three-level atom embedded in an anisotropic photonic crystal with two asymmetric bands. The property of spontaneous emission relating to the atomic position in a unit cell of the crystal is described with a position-dependent phase difference. The atomic transition in free space can be manipulated by the other associated transition coupling to photonic crystal. The result shows that the spontaneous emission spectra are effectively shifted and tuned by the atomic position-dependent phase, which results in the asymmetric distribution of the photonic density of states between two bands, and the increasing band can push the emitted light towards the other band. The physical process can be further illuminated through analyzing the emitted field in photonic crystal. The result perhaps offers an interesting route towards tunable photonic devices.  相似文献   
950.
信息化预拼装在钢结构成品检验中的应用   总被引:1,自引:0,他引:1  
我国的钢结构随着建筑业的高速发展应用领域也得到不断地扩大,复杂钢构件的成品检验成为了工程技术中的瓶颈。本文结合上海中心大厦项目的第三道环带桁架钢构件的信息化预拼装的操作过程,论述了综合利用三维建模软件对复杂空间杆件放样定位优势,以及全站仪精密测量空间坐标的特点,有效地解决复杂钢构件的检测难题,提高复杂钢构件制作精度,保障现场安装顺利进行。  相似文献   
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