Assessing the biodegradation potential of polymers in screening- and long-term test systems

This paper presents a test scheme for assessing the biodegradation potential of polymers, starting with aquatic screening systems (aerobic and anaerobic) and continuing to long-term systems. At the end of the scheme the material has to prove its behavior under the relevant disposal conditions. Aerobic screening was performed mainly under aquatic conditions, but also in soil, using BOD-respirometry. Carbon balances were performed to obtain a better evaluation of the biodegradation potential. Under anaerobic conditions, biodegradation in an aquatic medium was followed by measuring CH₄ and CO₂ production. Polymers not fully degraded in the screening systems were tested in aquarium systems for at least 1 year. Biodegradation was followed by monitoring the DOC released in the water, mass loss, and microbial growth on the samples and in the water as well as via FTIR spectroscopy and SEM pictures. Results are presented for the polymers PHB, PHBV, PCL, Mater-Bi AI05H and ZF03U, and Bioceta. By combining the data from the screening with the aquarium system, a good picture of the degradation behavior of the polymers is obtained.Paper presented at the Bio/Environmentally Degradable Polymer Society—Third National Meeting, June 6–8, 1994, Boston, Massachusetts.     

镉对鲫鱼过氧化物酶活性的影响

对鲫鱼的内脏组织的过氧化物酶（ＰＯＤ）活性正常值作了测定，结果表明：心脏和肾脏的ＰＯＤ活性较高，鳃和肝胰脏次之，肠和肌肉较低，当水中镉离子浓度为１６ｍｇ／Ｌ、３２ｍｇ／Ｌ时，肾脏、鳃的ＰＯＤ活性显著增强，肝胰脏的ＰＯＤ活性在３２ｍｇ／Ｌ组显著增强，心脏的ＰＯＤ活性在３种能离子浓度下影响均不明显。体外试验表明，镉不能直接影响ＰＯＤ活性。水体中加入ＥＤＴＡ（乙二胺四乙酸）可解除或减轻Ｃｄ＾２＋对鱼的毒     

金刚石钻进规程的实验室模拟及参数校核

金刚石钻进的钻进规程决定了钻进效率和钻头的使用寿命，也决定了钻进的安全性、可靠性和经济效益。因此，选择最佳的钻进规程尤其重要。本文通过智能微钻实验台对金刚石钻进的模拟钻进参数及其变化曲线、参数值，以及对应的钻进速度、进尺变化曲线、参数值进行分析，得到相应岩石条件下的最优钻进规程。     

纳滤膜深度处理自来水中有害物质的研究

采肜纳滤膜对某市自来水进行深度处理试验，结果表明：ＮＦ能有效地去除ＮＨ３－Ｎ、有机物，致突变物，无机离子等杂质。     

蚕豆根尖微核技术监测工业废水遗传毒性

用蚕豆根尖微核技术监测淮阴市冶金、化工、印染及制药行业废水的遗传毒性，结果表明淮明市部分工厂废水存在不同程度的遗传毒性。     

医药工业专用压力容器--开环反应罐的检测及安全评价

对医药化工合成专用设备－－开环反应罐进行了多年跟踪检测，积累了检测数据，对其安全可靠性进行了探索。     

Time series analysis of elemental and isotopic data from biomineralized whale tissue

A temporal record of environmental conditions is often contained within accretionary biological tissue. These records can provide knowledge of the environmental conditions that existed at the time the tissue was formed. In this study, we look at trace element concentrations and isotopic ratios of carbon and nitrogen as contained in baleen from bowhead whales in the eastern and western Arctic Ocean. Time series techniques, including maximum likelihood method and likelihood ratio tests, are applied to analysis of data and inference about their mean structures.     

Effects of some heavy metals on cell suspension cultures of Catharanthus roseus

ＥｆｆｅｃｔｓｏｆｓｏｍｅｈｅａｖｙｍｅｔａｌｓｏｎｃｅｌｌｓｕｓｐｅｎｓｉｏｎｃｕｌｔｕｒｅｓｏｆＣａｔｈａｒａｎｔｈｕｓｒｏｓｅｕｓＺｈｕＬｉｚｈｏｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅ），ＨａｎｇｚｈｏｕＵｎｉｖ...     

生物标志物

生物标志物技术是常规生物检测方法的必要补充，其在环境管理，风险性评价和生态恢复方面有着较广泛的应用，该文主要介绍了相对于常规生物检定方法而言，生物标志物所具备的优点，以及常用生物标志物的类型，生物标志物在环境保护领域的应用等