5 research outputs found

    Research on Tax Planning of Chinese Agricultural Enterprises

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    到目前为止,我国仍是个农业大国。农业是国民经济的基础,农业企业主体经济效益的好坏也直接关系到整个国民经济发展的全局。一方面,市场经济体制的建立,为各类经济主体提供了广阔的发展空间,同时也使得各类经济主体面临着激烈的市场竞争。各经济主体内部成本费用的压缩空间越来越小,而作为经济主体外部的税收,其数额的多少直接影响着企业的经营利润。因此,在“理性经济人”的假设下,企业都有进行税务筹划的动机。另一方面,我国税务筹划的理论研究尚处于初步探索阶段,针对农业企业税务筹划的理论研究更是缺乏。因此,对农业企业进行具体的税务筹划研究,不仅有助于我国税务筹划理论体系的完善,而且有助于促进我国农业企业的健康发展。 ...So far, China is still a large agricultural country. Agriculture is the basis of the entire national economy, and then the economic benefits of agricultural enterprises have a direct bearing on the overall development of national economy. On one hand, the construction of market economic mechanism provides many developing opportunities for different kinds of economic entities as well as fierce comp...学位:管理学硕士院系专业:管理学院会计系_会计学学号:1752006115120

    Electrophoretic Deposition of Nano Hydroxyapatite/Carbon Nanotubes Composite Coating and Its Characterizations

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    羟基磷灰石(HA)是人体骨骼和牙齿的主要无机成分,人工合成的HA具有良好的生物相容性和生物活性,但是HA脆性大、强度低,抗折强度和断裂韧性指标均低于人工致密骨的特性,从而限制了它在生物医学领域的应用。为此人们发展了各种HA的复合材料,期望HA保持生物活性的同时具有良好的力学性能。其中在医用金属钛表面涂覆HA活性涂层是目前复合生物材料领域的研究热点之一。目前发展了多种在医用金属钛表面涂覆HA活性涂层的方法,但是有各自的缺点。电泳沉积结合后续处理(烧结)因其操作方便、形貌厚度可控、不受基体形貌的限制而倍受欢迎。但是由于HA和金属Ti热膨胀系数的差异,在烧结降温的过程中,HA涂层与基体之间产生拉伸的...Hydroxyapatite (Ca10(PO4)6(OH)2, HA) is the main mineral component of bone in living hard tissues such as bone or teeth. The synthetic form of HA has great biocompatibility and bioactivity. Unfortunately, its poor mechanical properties properties inhibit its use in biomedical area. As a result, the significant research activity has been related to the development of all kinds of HA composites, esp...学位:理学硕士院系专业:化学化工学院化学系_物理化学(含化学物理)学号:20032507

    Electrophoretic Deposition of HA/CNTs Composite Coating

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    采用电泳沉积的方法在医用金属钛表面沉积纳米羟基磷灰石(HA)/多壁碳纳米管(MWCNTs)复合涂层.力学拉伸实验表明,所制备的纳米HA与MWCNTs的复合涂层可显著增强其与基底材料的结合力.体外细胞培养试验证明,电泳沉积制备的复合涂层具有良好的生物相容性.可望成为一种新的综合性能良好的硬组织生物材料.In order to enhance the bonding strength of hydroxyapatite (HA) coating to a metal substrate,and also improve its biocompatibility,the electrophoretic deposition(EPD) technique has been developed to prepare a composite coating of HA/multi-walled carbon nanotubes(MWCNTs) on a titanium substrate.It is indicated that after sintering at 700℃ for 2 h the adhesive strength of the prepared composite coating to the titanium substrate is increased as high as 35.44 MPa.And it is also demostrated,in vitro cell culture test,that the HA/MWCNTs composite coating is of a good biocompatibility.It is promising to develop a new hard tissue biomaterial with satisfied mechanical and biological properties.国家自然科学基金(20273055);; 教育部博士点基金(20020384012);; 国家863计划(2003AA302230);; 福建省科技重大项目(2003I001)资

    我国原铝冶炼行业温室气体排放模型

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    我国原铝冶炼行业产业集中度较低,生产水平参差不齐,随着国内原铝产量不断增加,原铝行业碳排放及其计算方法备受关注.针对我国原铝冶炼过程原料类型、能源结构复杂的特点,对国内外已有碳排放核算框架进行细化,从物料、工序、工艺3个层面构建了复杂的原铝冶炼系统温室气体排放计算模型.在广泛文献调研的基础上,选取典型原铝冶炼企业开展现场调研及专家咨询,进而形成模型的基础数据库.利用上述模型对我国2011年原铝冶炼过程碳排放进行核算.结果表明:综合考虑氧化铝生产工艺结构、电解铝行业分布区域的电网能源结构,我国原铝冶炼系统CO2排放因子(以铝锭计)为14.70 t/t.电解铝生产过程电耗相关排放占70%,南方电网区域电解铝生产电耗相关CO2排放分别比华中、华北地区低13%、30%.原铝冶炼行业可通过优先选用碳排放因子较低的物料、淘汰落后氧化铝工艺、开发引进低温低电压工艺技术等手段,进一步实现物料、工序及工艺的多层次温室气体减排
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