HPLC法测定利血平注射液的含量

建立反相高效液相色谱法测定利血平注射液中利血平的含量。方法：采用奥泰公司C18色谱柱（220mm×4．6mm,5μm）,乙腈-1％醋酸铵溶液（40：60）为流动相,检测波长为268nm,流速为1．0ml／min,柱温为30℃利血平在0．10～0．90ug·mL^-1范围内呈良好的线性关系（r=0．99996）。利血平平均回收率分别为99．5％。结论：本法简便、准确,可用于利血平注射液中利血平的含量测定。     

HPLC法测定叶酸片中叶酸的含量

目的:建立HPLC法测定叶酸片中叶酸含量方法。方法:采用C18柱(250×4.6mm,5μm)色谱柱;A液:0.10mol·L-1KH2PO4+5%乙腈,B液:70%乙腈水溶液,梯度洗脱为流动相;柱温35℃;检测波长270nm。结果:该方法在9.4380μg·m L-1~84.9416μg·m L-1浓度范围内具有良好的线性关系,R=0.99998;平均回收率为99.69%,RSD(%)=0.66%。结论:该方法准确、可行,适用于叶酸片质量控制方法。     

利福平胶囊制备工艺改进

本实验研究利福平腱囊的制备方法并建立反相高效液相色谱法测定利福平胶囊中利福平的含量。方法：采用安捷伦十八烷基硅烷键合硅胶色谱柱（218mm×4．6mm,5μm）,甲醇-0．02mol／L磷酸氢二钠一磷酸（80：20：0．01）,检测波长为254啪,流速为1．0ml／min,柱温为30℃。利福平在50～500μg·mL^-1%范围内呈良好的线性关系（r=0．9999）。结论：本制剂稳定、可靠、溶出度好。     

HPLC法测定参茸王浆口服液中10-羟基-2-癸烯酸的含量

目的:建立HPLC法测定参茸王浆口服液中10-羟基-2-癸烯酸的含量方法。方法:采用C18柱(250×4.6mm,5μm)色谱柱;甲醇-0.03mol/L盐酸溶液-水(55:10:35)为流动相;流速1.0m L·min-1;柱温30℃;检测波长210nm。结果:该方法 10-羟基-2-癸烯酸在50.05μg·m L-1~1000.99μg·m L-1浓度范围内具有良好的线性关系,R=0.99992;平均回收率分别为99.81%,RSD(%)=0.28%。结论:该方法专属性强,重复性好,可用于参茸王浆口服液中10-羟基-2-癸烯酸的含量测定及其质量控制。     

矸石混凝土充填方案及其采空区应力分布与沉陷分析

基于关键层失稳破断的临界尺寸理论对充填条带间隔距离进行了分析,对矸石混凝土柱及采空区进行了设计,给出四种研究方案,方案1为5m柱-10m采空区,方案2为5m柱-16m采空区,方案3为7m柱-14m采空区,方案4为6m柱-20m采空区,采用数值计算方法对上述四种方案垂直位移、水平位移、垂直应力及安全系数进行分析。基于上述提及的四类方案进行了数值计算,测试结果表明方案Ⅱ(5m矸石混凝土柱,16m不充填采空区)是最适合的充填方式。     

高效液相色谱法测定农药中的马拉硫磷

高效液相色谱法测定农药样品马拉硫磷,样品用甲醇溶液提取测定。本研究方法为使用XDB—C18（150mm×4．6mm）的色谱分离柱,70％甲醇：30％水（V／V）为流动相,流速为0．8m1／min,最佳波长为220nm的紫外检测器。研究结果表明,在10-100mg／L浓度范围内峰面积与进样量呈良好的线性关系,相关系数r=0．9989;检测限为10．5μg／L（S／N=3）;相对标准偏差RSDS（n=5）1．10％,回收率为95．5％以上。     

HPLC法测定肾衰宁胶囊中丹参酮Ⅱ_A的含量

目的:建立HPLC法测定肾衰宁胶囊中丹参酮IIA的含量方法。方法:采用迪马C18柱(250×4.6mm,5μm)为色谱柱;乙腈-0.01%磷酸溶液(70:30)为流动相;流速0.9m L·min-1;柱温25℃;检测波长270nm;进样量10μl。结果:该方法丹参酮IIA在60.76μg·m L-1~607.60μg·m L-1的浓度范围内具有良好的线性关系,R=0.9999;平均回收率为99.79%,RSD(%)=0.40%。结论:本方法准确,可靠,重复性好,能够用于肾衰宁胶囊的含量控制。     

高效液相色谱法分析和检测青梅花、枝、叶中有机酸的种类和含量

用高效液相色谱法检测青梅花、枝、叶中有机酸的种类和含量。色谱条件:色谱柱为Agilent TC-C18柱(250 mm×4.6 mmi.d.,5μm),流动相为含3%(V/V)甲醇的0.01 mol/L KH2PO4水溶液(pH2.85),流速1 mL/min,柱温30℃,紫外检测波长为210 nm。该方法相对标准偏差介于0.36%~1.61%之间,回收率在92.7%~104.2%之间,各种酸的线性相关系数r>0.9943。该高效液相法可以对柠檬酸、苹果酸、草酸、酒石酸、抗坏血酸、乳酸、醋酸、马来酸、富马酸和琥珀酸这10种有机酸进行快速、有效的定性定量分析。实验结果表明,梅枝30%乙醇提取物中有机酸总量为5.75%,主要是柠檬酸和酒石酸;梅叶30%乙醇提取物中有机酸总量为5.86%,主要是草酸和柠檬酸;梅花30%乙醇提取物中有机酸含量相对较低。     

固相萃取—高效液相色谱法测定大鼠血浆中β-榄香烯含量的研究

目的:建立一种稳定、准确测定大鼠血浆中β-榄香烯的固相萃取-高效液相色谱检测方法,为进一步系统开展该化合物体内药代动力学研究奠定方法学基础.方法:β-榄香烯血浆样品经固相萃取柱萃取后,采用高效液相色谱法检测,色谱柱为Waters Navpack C1s柱(150×3.9mm i.d.,5μm),柱前接Waters C18预柱(8×4mm,i.d.,5μm),流动相为乙腈:水(90:10,v/v),流速1.0 mL·min-1,柱温30℃,检测波长210 nm,内标为蓬莪术环二烯.结果:大鼠血浆中β-榄香烯含量的线性范围为0.147～ 5.88μg·mL-1,R=0.998,.方法日内精密度与日间精密度均≤15％,萃取回收率≥71％.结论:本研究建立的β-榄香烯血药浓度测定方法有较高的准确度和灵敏度,适用于该化合物的体内药代动力学研究.     

HPLC法测定生脉饮口服液中五味子醇甲的含量方法研究

目的:建立HPLC法测定生脉饮口服液中五味子醇甲的含量方法。方法:采用C18柱(250×4.6mm,5μm)为色谱柱;甲醇-水(13:7)为流动相;流速1.0m L·min-1;柱温35℃;检测波长250nm;进样量10μl。结果:该方法五味子醇甲在60.76μg·m L-1~607.60μg·m L-1的浓度范围内具有良好的线性关系,R=0.9999;平均回收率为99.79%,RSD(%)=0.40%。结论:本方法简便准确,快速可靠,能够用于生脉饮口服液的含量测定和质量控制。     

Students' Reactions to the Introduction of Videoconferencing for Classroom Instruction

This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors.     

Cooler temperatures inductive to locust outbreaks

Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007.     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction.     

Low doses of a red wine ingredient figh diabetes in mice

Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said.     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies.     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means.     

Rough Justice: A Statistical Assessment of ICANN's Uniform Dispute Resolution Policy

Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP.     

Prevalence of soft neurological signs in Chinese people

Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.     

Molecular motor assembly of a biomimetic system

Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction.     

Monoculture Rubber Plantations Have Negative Ef ects on Controlling Splash Erosion

<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence