17 research outputs found

    An Analysis on the Core Competences of China Export & Insurance Corporation

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    出口信用保险是一国政府以国家信用作为支持,通过提供风险管理、收汇保障和融资便利等功能,支持本国企业出口的一项政策性措施,是实施国家外交、外贸及产业政策的有力工具。虽然,中国出口信用保险公司(简称:中国信保)目前仍属于政策性保险公司。但外资信用保险公司觊觎中国信用保险市场已久,信用保险市场改革的呼声越来越高。因此,中国信保必须做好长期的战略规划,在变革中求发展。 本文从中国信保的发展现状进行研究,介绍了中国信保的主要保险产品情况,分析了从2002年中国信保成立以来公司的经营情况以及业务的发展状况。总结出了中国信保的发展战略,即在竞争来临之前,继续高举政策性旗帜,尽快占领信用保险市场的主导地位同...Export credit insurance is a policy-oriented measure to promote a country’s export through providing export enterprises with receivables insurance, risk management and finance facility. It is a powerful instrument to realize national diplomatic and foreign trade policies under the supporting of national credit. Though China Export & Credit Insurance Corporation (“SINOSURE”) is the only policy-...学位:管理学硕士院系专业:管理学院工商管理教育中心(MBA中心)_工商管理硕士(MBA)学号:1792006115155

    Application of Raman Spectroscopy for Analysis in Radiosensitivity of Total Protein of Nasopharygeal Carcinoma Cells

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    本文以鼻咽癌细胞株CnE2为放射敏感性的研究对象,经不同剂量X射线照射及不同时间培养后分别提取总蛋白,用共聚焦显微拉曼光谱仪检测其拉曼光谱。统计分析表明:被测样品的拉曼光谱中观察到一些可以归属于蛋白质物质的较为明显的基团频率振动峰;不同剂量的X射线照射后,总蛋白质的平均拉曼光谱与对照组谱形基本一致,但与对照组间的光谱存在着对应峰信号强度的不同。实验提示:照射后谱峰强度的增大或减小,提示着相关物质含量有所改变。分析照射后癌细胞总蛋白拉曼光谱的变化情况,结合数学统计方法,以探寻放射敏感性的特征拉曼标志,可以作为研究肿瘤放射敏感性的手段之一。To study the effects of total protein of nasopharyngeal carcinoma cell line CNE2 treated by different doses of X-ray irradiation.The total protein is extracted from the cell line and detected by confocal micro-Raman spectroscopy.Both t test and support vector machine are employed via SPSS and LIBSVM software packages for statistical analysis of Raman spectrum.The results show that several Raman bands assigned to total protein can be detected; and the X-ray irradiation have various effects on different components in total protein,and related to the radiation dose.It was indicated that in spite of no significant diversification on structures of protein,the content may be varied during irradiation.国家自然科学基金项目(11104030); 福建省自然科学基金项目(2011J01153

    磁性固定化酵母细胞颗粒的研制

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    <正> 一、前言酶、微生物、植物和动物细胞固定化技术的研究和应用是当前生物工程发展的重要研究课题之一。近几十年来,工程科学家们一直探索、改良作为酶源的微生物,建立酶和细胞的固定化技术,期望把酶及微生物甚至于动、植物细胞制成块状的工业催化剂,以便用于各种新型反应器;并企图实现工业化、连续化、自动化地稳定生产。因此,制备活性高,稳定性好、强度大、成本低、适用的固定化生物催化剂仍是科研工作者当前面临的一个重要课题。本文主要研究了酵母细胞固定化技术和球型颗粒的制备以及应用于酒精发酵的某些特征

    酒精生产的新技术——固定化细胞法及固定化细胞反应器

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    本文介绍了国外固定化细胞法生产酒精的现状,并对细胞固定化所用的各种载体及固定方法进行了比较。固定化细胞法优于传统的悬浮细胞法,固定化细胞反应器是生产酒精的高效和高选择性生物反应器

    外循环流化床生物反应器的特性及应用

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    针对固定化增殖细胞发酵酒精的特点,研制与开发了一种新型外循环流化床生物反应器和大规模制备固定化细胞颗粒的方法和装置。考查了固定化细胞颗粒流化特性,外循环速度对液相停留时间分布的影响,宏观发酵动力学及固定化增殖细胞发酵酒精的特点及历程。设计并完成了665L 中试规模的放大试验,连续运转近3个月。实验结果表明:以未处理无灭菌的废甘蔗糖蜜为原料,用海藻酸钙包埋的固定化酵母颗粒连续发酵酒精,终酒精浓度为8~10%(v/v),对糖收率>92%,反应器生产能力达12kg/(m~3·h)

    历山山地草甸的生态关系

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    以山西历山的舜王坪草甸为研究地,运用TWINSPAN和DCA相结合的数量生态方法对9个群落进行划分,得到一个明显的随放牧强度变化的群落序列,即从群落III、IV到群落V、VI再到群落VIII,分别为过牧阶段、中牧阶段和轻牧阶段。可见,利用TWINSPAN和DCA相结合可对不同放牧强度的群落进行划分和排序。从草甸的生态关系研究得出历山山地草甸退化的主要原因是人为干扰。运用DCCA排序法,综合样方和土壤环境因子信息,定量综合研究了放牧草甸与周围土壤环境的生态关系。DCCA第一轴也表现为放牧梯度,在过牧阶段的群落中,有机质和N的含量较高,土壤的退化滞后于植被资源的退化;而在轻牧阶段的群落中,营养元素含量较高

    固定化细胞磁场流化床反应器连续生产乙醇的研究

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    本文用海藻酸钠—Mn—Zn 铁氧体磁粉包埋酵母,在有效总容积为3.5升的三层磁场流化床反应器系统中,实现了由糖蜜为原料发酵生产酒精,连续运转了28天。实验结果表明:发酵底物糖的浓度为154.6(g·1~(-1)),停留时间2.67hr,糖转化率达96.4%,流出乙醇浓度为51.6(g·1~(-1)),生产能力为19.32(g·1~(-1)·hr~(-1))。该体系宏观发酵动力学测定为:r=r_(max) S/(K_m~(app)+S)·(1-P/(Pm))r 是反应速度,S 为糖浓度,P 为乙醇浓度

    The Influence of Environmental Facts on Growth Rate of an Explanted Marine Sponge Mycale phyllophila

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    海绵动物是重要的药源生物,由于自然海区生物量较少,限制了它的开发以及应用,海绵的人工增殖被认为是最有效解决海绵药源供给的途径.本研究以福建沿海广泛分布的山海绵属(MyCAlE)的种类为研究对象进行了初步的海区增殖研究.叶片山海绵(MyCAlE PHyllOPHIlA)属于寻常海绵纲(dEMOSPOngIAE),繁骨海绵目(POECIlOSClErIdA),山海绵科(MyCAlIdAE),山海绵属.研究了养殖深度,海水流速,附着基大小等3种因素对叶片山海绵在自然海区生长速度的影响.结果显示,不同移植环境中叶片山海绵成活率均为100%,且都具有较快的生长速度.最快的生长速度出现在水深2.0M,流速较缓,附着基面积为75CM2的实验组,2个月平均增长率达472.1%.环境因子的多重方差分析结果显示,水深和水流对叶片山海绵的生长速度影响显著(P<0.05),较浅的水深、较缓的水流更有利于叶片山海绵的生长.叶片山海绵未全部覆盖附着基前,附着基的大小对叶片山海绵生长速度的影响不显著.Marine sponges are a diverse taxon of benthic aquatic animals of great biopharmaceutical importance.However,the lack of sufficient supply of sponge biomass restricts their preclinical and clinical application.In situ sponge aquaculture is nowadays one of the most reliable methods to supply of biomass for drug development.In this study,we focus on the aquaculture of the sponge Mycale phyllophila,which has a potential usage for biological medicine and commonly distributed along the southeastern of China coast.Culture efficiency were evaluated by determine of sponge survival and growth rates under different aquacultural factors,such as culture depths,water flow rates and explant sizes.The survival rates of explants were achieved 100% in all experimental groups.Relatively fast growth rates also were achieved,among which,the fastest group reached a growth rate of 472.1% after 60 days′ culture.Deeper culture depths and slower water flow is more conducive to the growth of the sponge.No significant difference of growth rates were detected among groups with different explant sizes.中央高校基本科研业务费专项(2010121034); 福建省自然科学基金项目(2011J01245

    Comparison of samples preservation and DNA extraction of sponges

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    海绵标本长期、完整的保存是开展海绵分类学及分子进化研究的重要前提,本研究以建立通用的海绵动物标本的保存方法及快速、完整的基因组dnA提取方法为主要目的,通过对硅质的山海绵(MyCAlE SP.)和钙质的白枝海绵(lEuCOSOlEnIIdAE SP.)为材料进行–20℃冰冻、乙醇固定、冰冻后风干和乙醇固定后风干等4种保存方法进行研究,同时采用酚-氯仿法、高盐法、CTAb法等3种基因组dnA提取方法,测试了4种保存方法的dnA提取效率。实验结果显示,海绵样品的4种保存方法以及3种dnA提取方法对于硅质海绵以及钙质海绵虽然在提取的dnA得率上有差异,但都能获得较高纯度基因组dnA。从经济成本、方便性、潜在的污染等因素考虑,高盐法是首选的提取海绵基因组dnA的方法;乙醇固定保存的海绵样品dnA得率最高,冰冻的海绵样品得率最低,推荐采用乙醇固定保存海绵样品的方法。In order to build the optional method of sponge preservation and a safe, fast and effective genomic DNA extraction method, different ways of DNA extraction and preservation were studied in this paper.Two different species, Mycale sp.and Leucosoleniidae sp., and four different ways of preservation including 20℃ freezing,ethanol fixation, air drying and ethanol fixation then drying were tested,.Three methods for DNA extraction including cetyltrimethylammonium bromide(CTAB), Phenol – Chloroform and high salt extraction were examined.The results show that each method can obtain high quality genomic DNA.But considering economical, enviromental friendly and convenient factors, the method of high salt extraction was the best one among the three methods of DNA extraction.The amount and purity of DNA isolated from ethanol fixed specimens were the best.In a word, the ethanol fixed is the best method of sponge preservation.中央高校基本科研业务费专项资金资助项目(2010121034); 福建省自然科学基金资助项目(2011J01245
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