蜂蜜中氯霉素残留的检测及净化方法研究

建立了反相高效液相色谱-离子阱质谱法检测蜂蜜中氯霉素残留的方法.前处理采用改良的QuEChERS方法进行快速提取和净化.采用初级次级胺进行固相分散净化,可有效吸附蜂蜜中的糖类及有机色素等杂质.提取物在流动相甲醇:水(0.2%乙酸胺)=45:55(体积比)中,用整体色谱柱进行快速分离和质谱检测.并对MS检测中2种离子化方式(电喷雾ESI及大气压化学APCI)、各种离子化方式下正负离子模式及离子检测方法(总离子检测TIC和选择性离子监测MRM)进行了综合比较,最终确定采用电喷雾电离法(ESI)负离子模式、多反应离子监测(MRM)对氯霉素进行定性定量分析.在0.2～200μg/kgg添加浓度下,添加回收率水平在78%～93%间,变异系数在3.9%以下.该方法的检出限为0.1μg/kg,在0.1～100 μg/L浓度范围内,线性方程为y=58.753x 34867,相关系数R2=0.999 5.     

Impact of the FTSE4Good Index on firm price: an event study

This paper examines whether corporate financial performance is affected by public endorsement of environmental and social performance. Event study methodology, which relies on the notion of market efficiency, is used to examine the relationship between positive and negative announcements and changes in share prices or daily returns. Inclusion in and deletion from the FTSE4Good UK Index is used as a proxy measure for good (poor) corporate social responsibility. The abnormal or unexpected daily returns associated with an event are calculated and their significance tested. The results show a trend towards positive and negative announcements having the expected effects on daily returns. But these movements are not significant and the data do not suggest that a firm's presence on the index brings it any significant financial return for signalling its corporate social responsibility.     

Environmental management and firm performance: a case study

This study has as its aim to help to clarify the relationship between environmental management and economic performance by integrating it into a wider framework that includes the relationship between environmental strategy and firm performance, the latter being understood as the combination of environmental performance, competitive advantage and economic performance. A case study of the COATO farming cooperative showed us that its environmental management, focused on prevention logic, has had a positive net effect on its environmental performance. Besides, the order in which these practices were adopted favoured the development of new organisational capabilities that have contributed to the appearance of advantages derived from the greater accumulated experience of employees in creating new projects that are designed to reduce residues and pollution. COATO has also obtained a competitive advantage in differentiation thanks to an improved brand image and to its increased credibility in business relationships. Finally, a positive correlation exists between the pioneering proactive strategy adopted by this cooperative and the improvement of its firm performance with respect to the other firms in its sector.     

Empirical investigation of construction safety management activities and performance in Australia

The construction industry seems to suffer from a general inability to manage workplace health and safety to a level where an achieved improvement in safety performance by a way of pro-active measures can result in zero accidents. This paper investigates the effectiveness of safety management activities as currently adopted by Australian contracting organisations. A safety management survey has been conducted of contracting organisations operating in the State of Queensland, Australia. Based on a research model depicting statistical analysis techniques, a safety management index reflecting the intensity of level of safety management activities has been developed to provide a means whereby individual organisations can be assessed and graded on their safety management commitment and attitudes. The paper reports on a detailed empirical analysis carried out to examine the relationship between the intensity of safety management commitment and the overall safety performance, pro-activeness and record.     

Supporting organizational learning by comparing activities and outcomes of the safety-management system

The approach to support organizational learning from pro-active monitoring (activities observations) and deficiencies revealed (outcomes observations) in process-safety incident investigations is proposed.The approach builds on five main steps: i.) Implementation of the incident-investigation procedure at the company level, ii.) Monitoring of the preventive safety activities using various tools, iii.) Identification of the safety outcomes including root-cause analysis, iv.) Comparison of activities observations with outcomes observations in order to reveal latent deficiencies as well as to proof relationships, v.) New universal indicator method is proposed to enhance organizational learning from both activities and outcomes observations.The approach is demonstrated on the implementation at the anonymous SME company. This involved carrying out activities observations in terms of the SMS internal audit and the ARAMIS and the violation-motivation safety-culture questionnaire surveys. The outcomes observations consisted of the three incidents investigations using ECFA+, 3CA and MORT methods. The approach and the case study enabled demonstration of the relationships between activities observations (preventive indicators) and outcomes observations (root causes/deficiencies indicators) and vice versa. We state that such a comparison adds to the justification of the preventive safety performance indicators. Finally, in order to ease the organizational learning from both activities and outcomes observations, universal management indicators attributes/categories are suggested to be followed and are briefly explained based on a modified REWI approach.     

铜铝复合式CPU风冷散热器的实验研究

随着计算机的迅猛发展，CPU芯片的集成度、封装密度以及工作频率的不断提高，其发热量也不断增大，从而对CPU散热器的散热性能的要求也提高了．通过分析散热器的散热性能及性能评价方法，对放射状铜铝复合式CPU散热器进行了测试，建立不同风速下功率与CPU表面平衡温度关系曲线和不同风速下功率与热阻关系曲线，为改进散热器提供了实验数据．图3，参5．     

矿用耐崩风筒在掘进迎头的性能研究

进行矿用风筒现场应用的实际性能实验，可以全面直观的检验风筒的通风性能和抗炮崩能力，对于风筒产品的质量考核和掘进迎头的通风安全具有重要意义。本文针对新型Kevlar耐崩风筒，研究矿用风筒性能的判定指标和检测方法，并在全岩巷道掘进工作面、半煤岩巷道掘进工作面以及全煤巷道掘进工作面进行Kevlar风筒现场应用实验，与我国目前矿山普遍使用的玻纤布风筒的现场应用进行对比，从物理机械强度、通风性能以及掘进成本等方面分析Kevlar耐崩风筒的实际性能，研究Kevlar风筒替代玻纤布风筒的可行性。经过现场应用的实验和检验，Kevlar风筒比目前国内应用的玻纤布风筒性能优越，具有经济、安全、耐用、便捷的特点。     

The work of Envirowise in driving forward UK industrial waste reduction

Envirowise — formerly the Environmental Technology Best Practice Programme — is an UK Government Programme designed to help businesses to improve environmental performance and reduce costs. It works closely with industry bodies to prepare a strategic approach to producing and promoting tools that help companies take action to reduce waste at source. By September 2000, the Programme had helped UK companies to save £125 million per year by reducing the use of raw materials and the production of waste. The Programme produces practical advice based on existing practices in industry. As well as producing published information, Envirowise runs a free telephone helpline for UK companies. Envirowise undertakes a considerable amount of marketing to help companies overcome the barriers to action. The Government has set the objectives for the Programme's managing contractors; these are based on the impact of its activities in terms of reduced waste production.     

DCL型燃煤固硫剂固硫技术在广州石化热电站的应用

随着环保要求的日趋严格，燃煤锅炉的脱硫已势在必行，DCL型燃煤固硫剂脱硫技术是中科院“九五攻关”项目之一，其技术原理是通过添加助剂提高固硫剂的吸附表面及其活性，同时将SO2转化为SO3或使MeSO3转化为MeSO4，从而使CaO固硫率大大提高，本文介绍了DCL型燃煤固硫的技术特点，因硫原理，固硫工艺和固硫设备及其在广州石化热电站的应用效果，通过运行数据分析和成本比较，证实DCL固硫剂固硫技术的适用性。     

混菌接种条件下微生物燃料电池芯片的产电特性研究

微生物燃料电池(MFC)芯片因具有体积小、运行条件温和、产电稳定等优点而有可能成为一种新型的野外水环境监测系统中传感器供能方式.但目前采用纯菌种及贵重金属阳极构建的MFC芯片,不仅成本较高且纯菌种在复杂环境条件下不易存活和保持稳定.因此,本文通过采用混合菌群接种,以活性炭为阳极,构建了阳极体积为50μL的MFC芯片,发现其稳定运行最大输出电流为3.5μA,平均运行周期为8.0 h,最大输出功率约为160 nW,最大功率密度为10.2 mW·m-2.EIS分析结果表明,MFC芯片的总内阻约为35.6 kΩ,其中,阴阳极内阻占主要部分.本研究制备的MFC芯片产电性能达到了同类采用纯菌株及Au作阳极的MFC芯片的性能,表明采用低成本材料为阳极,接种混合菌液的MFC芯片是完全可行的.