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61.
精馏过程的节能,对于减少能源消耗,降低生产成本和保护环境具有十分重要的意义.在精馏过程中可以采用最适宜回流比操作和最佳进料状态,使用中间冷凝器和中间再沸器,高效精馏、热泵精馏.合理安排多组分物料分离流程,直接利用过程热量及开发应用高效换热器等措施.本文从最佳回流比R的选择、进料温度及进料状态的确定等方面,详细的分析了在精馏塔的设计过程中,如何实现设计的优化问题,以实现节能降耗.  相似文献   
62.
In the present paper, we model the policy stance of the People's Bank of China (PBC) as a latent variable, and the discrete changes in the reserve requirement ratio, policy interest rates, and the scale of open market operations are taken as signals of movement of this latent variable. We run a discrete choice regression that relates these observed indicators of policy stance to major trends of macroeconomic and financial developments, which are represented by common factors extracted from a large number of variables. The predicted value of the estimated model can then be interpreted as the implicit policy stance of the PBC. In a second step, we estimate how much of the variation in the PBC' s implicit stance can be explained by measures of its policy objectives on inflation, growth and financial stability. We find that deviations of CPI inflation from an implicit target and deviations of broad money growth from the announced targets, but not output gaps, figure significantly in the PBC's policy changes.  相似文献   
63.
介绍了电镀镍污泥浸出工艺中氨回收的工艺流程、使用原材料和各单元操作,并对各单元操作的技术条件进行了理论分析和实践检验.  相似文献   
64.
国资监督机构在深化国资国企过程中应集中调配产权权益,完善资产负债结构,优化资源配置,通过资本运营和良好的市场环境,充分发挥中央和地方政府的职能,在互为尊重的前提下,杜绝侵权行为的发生。  相似文献   
65.
Three denim jeans products from the same manufacturer with differentiated pricing and labels (antiqued, sandblasted, and stonewashed) were used to determine the relationship between price and quality. Both qualitative and quantitative procedures were used to analyse the garments. All three jeans were made of twill weave with 3 × 1 repeat. Both structural and performance characteristics were compared using standardized tests. Analysis of variance was used to compare the selected structural and performance characteristics among the three jeans products. Tukey’s HSD tests were used for post hoc multiple comparisons for three jeans. The findings revealed that despite the fact that all three jeans products were from the same store, and that the fabrics used the same weave, degree and direction of twist, the jeans differed significantly for several structural and performance characteristics. Several possibilities for future research were explored.  相似文献   
66.
The Amazon is the largest tropical forest area on Earth, and has been undergoing rapid deforestation for the last four decades. In the Brazilian Amazon, large‐scale pasture for cattle ranching and soybean production are the main land uses, leading to a yearly deforestation rate of 0.5%. These conversions are mostly located in frontier areas distributed along the so‐called “arc of deforestation”. Within this large zone, various land use change processes are interacting through several modes of land valuation and organisation. From several case studies in the State of Pará (Brazil), the current project aims at analysing how landscape dynamics are related to infrastructure development, ecological conditions, zoning policies and to the evolution and the organisation of the production, consumption and marketing chains of livestock products. This paper presents the results for one test site, the region of São Félix do Xingú, South of Pará This region is the focus of land speculation, cattle expansion, and deforestation. Road construction, investments in electrical energy, financial credit for cattle, and the land reform policies have all fuelled this process. All these factors make this region one of the most dynamic agricultural frontiers in the Brazilian Amazon. The main objective of the paper is to improve our understanding of deforestation processes by crossing spatial analyses and 1ivestock economics.studies, and to characterise the role and impact of various natural and anthropic factors in the location and development of the main types of farmers, and their policy implications.  相似文献   
67.
This paper is focused on the cost of raising capital in Germany. A cross-sectional analysis of flotation cost data for 117 IPOs over the years 1993–1998 is presented. We find average flotation costs to be 7.77 percent of gross proceeds, while underwriting fees average 5.01 percent. Our results extend the literature in two important directions. First, contrary to the conventional economies of scale view we find marginal spreads to be rather constant in gross proceeds and to be higher for more risky and more complex offerings. Fixed costs amount to 5 to 9 percent of underwriting fees. Second, by applying a principal component analysis we find issue size, an issuer risk factor, and an offering method complexity factor to have an economicaly meaningful impact on underwriting fees.  相似文献   
68.
根据生殖健康的内容 ,将生殖健康产业划分为两大市场和 7类产品。通过对人口、购买力和购买欲望发展趋势的分析 ,提出中国生殖健康产业市场需求潜力巨大的预测。在培育生殖健康产业的过程中 ,产业发展要素的协调、市场化的策略与步骤、多方面合作的机制是政府目前需要优先考虑的三大问题  相似文献   
69.
对外贸易的拉动作用是实现我国十六大经济增长目标的重要保证。但是,反观当前的国内外环境,我国进出口贸易的发展遇到了诸多困难。欲解决这些问题,必须进行制度创新,其中培育城市群是一种可行的办法。而环渤海区域以其特有优势,成为培育对外贸易城市群的首选。为此,我国需要在环渤海区域大力发展高新技术产业,培育产业集群,引导民营企业发展,以及发挥政府的政策作用。  相似文献   
70.
This paper investigates the existence of a correction mechanism for mis-pricing between Japanese stock and bond. By this correction mechanism we mean that when deviations occur from the equilibrium levels of the expected return differentials between stock and bond — the risk premium differentials, the market will tend to correct the mis-pricing and bring the expected return differentials back to the equilibrium levels. We assume that the yield spread between the predicted earnings price ratio of stock and the yield to maturity of bond reflects the risk premium between stock and bond, and estimate the equilibrium risk premium differentials and mis-prices between stock and bond by modelling their behaviors with a statistical yield spread model (SYS). Empirical results strongly indicate the existence of the mis-pricing correction mechanism, suggesting the inefficiency of securities markets.  相似文献   
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