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我国中小企业融资问题简论 总被引:1,自引:0,他引:1
罗哲 《兰州交通大学学报》2007,26(5):27-32
融资困难是不同时期各国中小企业普遍面临的重要问题之一.本文通过中小企业与国有企业融资的对比分析,考察了我国中小企业融资困难的原因和相应策略.作者认为,中小企业自身发展的特点、融资渠道与融资风险、金融机构和社会服务体系等的综合作用是造成中小企业融资难的根本原因,而破解中小企业融资难的基本思路就在于政府、市场和中介组织的共同创新与发展. 相似文献
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The most commonly used and studied hybrid halide perovskite is ABX_3, where A usually stands for CH_3NH_3, B for Pb, and X for I. A lead-free perovskite with high stability and ideal electronic band structure would be of essence, especially considering the toxicity of lead. In this work, we have considered 11 metal elements for the B site and three halide elements(Cl, Br, and I) including various combinations among the three halides for the X site. A total number of 99 hybrid perovskites are studied to understand how the crystal structure, band gap and stability can be tuned by the chemistry modification, i.e., the replacement of toxic element, Pb in the original MAPbX_3, with non-toxic metal elements. We find that the favorable substitutes for Pb in MAPbI_3 are Ge and Sn. 相似文献
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