积极财政政策下的国债投资退出机制研究

自1998年我国开始实施积极财政政策以来,国债发行开始进入一个新的增长时期,由于国债增长过于迅猛,使人们担心政府财政特别是中央政府财政面临的债务风险问题。本文想从政府的债务风险着手,研究国债投资以后如何进行国债资金的回收用于归还债务,解决中央政府将来可能出现的债务风险

投资结构优化的税收优惠政策研究

我国的税收优惠政策是伴随经济的改革开放而产生、发展的，在引进外资、发展经济、提高科技水平等方面起到了十分重要的作用。但在经历了20年的经济、社会巨大变革之后，原有的税收优惠政策的积极作用已开始逐渐削弱，负面作用日益显现，由此引发了理论界、实际工作部门对税收优惠政策的重新思考。本文从我国税收优惠政策产生的背景出发，探讨了在税收优惠政策基础发生变化时，应如何适时调整原有的税收优惠政策，以期更好适应未来我国经济发展的需

The Private Firms vs.the Development of Corporate Bonds Market in China

文中认为 ,我国企业债券市场发展落后于股票市场的主要原因在于对发行主体局限于国有企业 ,发展企业债券市场的关键在于打破企业经济性质 ,按照市场条件进行审批 ,其中特别指出民营企业在目前已具备做为债券发行主体的市场条件 ,并为完善企业债券市场提出了一些建议The reason that the corporate bonds market lags behind the stock market lies in the fact that the issuing bodies are only limited to state owned enterprises.The key to developing the corporate bonds market is in going beyond the nature of the ownership of the firms on the one hand and regulating the issued firms based on its marketing quality on the other.The authors argue that the private firms have been qualified for issuing the bonds,and offer some suggestions to improve such bonds market

Determination of Alkylphenol in Water Samples by Stir Bar Sorptive Extraction Based on Poly(vinylimidazole-divinylbenzene) Monolithic Material and Liquid Chromatographic Analysis

建立了简单、快速、灵敏测定水环境中的双酚A(bPA)、辛基酚(OP)、壬基酚(nP)的方法。以聚(n-乙烯基咪唑-二乙烯基苯)整体材料为涂层的搅拌棒固相萃取技术富集目标物,然后与高效液相色谱-二极管阵列检测器联用测定水样品中烷基酚类污染物。考察了萃取时间、解析时间、样品基质的PH值、离子强度等实验条件对萃取效率的影响。在最佳条件下,3种目标化合物的线性范围是1.0~200μg/l,检出限lOd(S/n=3)在0.13~0.66μg/l之间,定量限lOQ(S/n=10)在0.44~2.19μg/l之间。在对海水和污水处理厂的实际水样测定中,3种目标化合物的不同加标水平的回收率为37.8%~101.1%。本方法具有简便、快速、高效、灵敏等优点。A method for the determination of bisphenol A,octyphenol,nonylphenol in water samples was developed using stir bar sorptive extraction(SBSE) based on poly(vinylimidazole-divinylbenzene) monolithic material(SBSEM) combined with high performance liquid chromatography with diode array detection.To achieve the optimum extraction performance,several main extraction parameters,including extraction and desorption time,pH value and contents of inorganic salt in the sample matrix,were investigated.Under the optimized experimental conditions,the method showed good linearity and repeatability,low detection limits (S/N=3) and quantification limits(S/N=10) of the proposed method for the target compounds were achieved within the range of 0.13-0.66 and 0.44-2.19 μg/L,respectively.The extraction performance of SBSEM to the target compounds was also compared with commercial SBSE which used polydimethylsiloxane as coating.The proposed method was successfully applied to the determination of the target compounds in water samples.The recoveries of spiked target compounds in real samples ranged from 37.8%-101.1%.The results indicated that the developed method possessed advantages such as sensitivity,simplicity,low cost and high feasibility.国家自然科学基金(No.20805039);福建省青年科技人才创新项目(No.2006F3117)资