’86国际焊接技术及设备洽谈展销会在我校举行

深圳’86国际焊接技及设备洽谈展销会于3月17日-26日在深圳大学举行。这次会议由深圳市精密机械制造有限公司和香港威利焊接器材有限公司联合举办,并得到了深圳市政府及有关方面的大力支持。参加展出的有ESAB等十家外国及香港地区的公司和国内八家工厂的产品。与会的146名代表,分别来自工厂、研究所、设计院和大专院     

Inhibitory effect of Cr（Ⅵ） on activities of soil enzymes

To evaluate the influence of various Cr(VI) concentrations (0.05, 0.25, 0.50, 1.00 and 2.00 g/kg) on the activity of soil enzymes, the activities of catalase, polyphenol oxidase, dehydrogenase, alkaline phosphatase in soils were investigated in the incubation experiment with a period of 35 d. The results indicate that all the tested Cr(VI) concentrations significantly inhibit dehydrogenase activity by over 70% after 35 d. The activity of alkaline phosphatase is slightly inhibited during the whole experiment except for on the day 7. Cr(VI) has no obvious effect on the activity of catalase in soil. On the contrary, Cr(VI) stimulates the activity of polyphenol oxidase. The results suggest that dehydrogenase activity can be used as an indicator for assessing the severity of chromium pollution. Foundation item: Projects(2006AA06Z374, 2007AA021304) supported by the National High-Tech Research and Development Program of China; Project(2008SK2007) supported by the Key Program of Science and Technology of Hunan Province, China     

Selective leaching of chromium-containing slag by HCl

A batch of column experiments was carried out to investigate the change of Cr（Ⅵ） concentration leached out from chromium-containing slag with HCI as leaching agent, and to study influences of pH, ratio of solid mass to solution volume, flow velocity and temperature on Cr（Ⅵ） leaching. The optimal parameters were obtained for Cr（Ⅵ） leaching and a fitting model was established to describe the procedure of Cr（Ⅵ） leaching. The results show that Cr（Ⅵ） concentration in leachate increases with decreasing pH and increasing flow velocity and temperature. Moreover, Cr（Ⅵ） leaching percentage increases with increasing ratio of solid mass to solution volume. The optimal parameters for Cr（Ⅵ） selective leaching are as follows： pH=3.0, 1：5 of ratio of solid mass to solution volume, 180 mL/min of flow velocity and 40 ℃ of temperature. The procedure of Cr（Ⅵ） leaching fits well with the model： v= 1.87t^-0.54, indicating that the leaching rate of Cr（Ⅵ） declines in an exponential order of-0.54.     

长石溶解-沉淀的热力学和动力学特征及其对储层物性的影响——以渤海湾盆地渤南洼陷沙三段为例

长石溶解及其次生孔隙的形成对砂岩储层质量具有重要影响。为了研究渤海湾盆地渤南洼陷有利孔隙发育带,利用长石溶解-沉淀的热力学和动力学计算,结合薄片分析、孔隙度和渗透率资料,开展了对沙三段长石次生孔隙发育的研究。结果显示,现今的地层水多有利于长石沉淀,部分区域发生长石溶解。结合孔隙度平面分布图和镜下薄片分析可知：孔隙度发育较好的区域主要是钾长石发生溶解,钙长石ΔG < -15 kJ/mol溶解速率较快和钠长石ΔG < 15 kJ/mol沉淀速率较慢的区域。此外,粘土矿物（高岭石等）在长石溶解形成的次生孔隙中的沉淀,降低了储层的渗透率;且在埋深超过3 000 m的区域,地层水中的SiO₂（aq）沉淀速率的显著加快降低了储层孔隙度。综上：埋藏环境中,长石的溶解对于次生孔隙的贡献十分重要,但是如果其副产物未发生迁移则对次生孔隙的贡献较小,并且较高的粘土矿物含量会降低储层的渗透率。本文对于利用热力学和动力学模型预测储层发育提供了新的方法。     

“突出特色,适应发展”专业实验室改造的对策与实施

为培养学生工程实践能力,给校内实习提供一个真实的工程环境,针对沈阳工程学院电气运行实习厂设备陈旧的问题,提出改造设想,经过论证,并付诸实施.同时介绍了电气防误操作系统的构成和功能以及在电气运行实习中发挥的作用.实践表明,电气运行实习厂设备改造工程是成功的.     

变压器屏蔽对开关电源电磁干扰(EMI)影响的分析

从变压器屏蔽对电源的EMI的作用入手，分析了屏蔽所影响的EMI的特性和传输路径，并通过仿真研究了屏蔽层对变压器损耗的影响。最后给出了一个改变屏蔽以简化变压器的制造的例子。     

遥控器漫谈

现今遥控器以各种形式或载体走进了千家万户,每个家庭都拥有若干类型的家电,相应遥控器就有一大堆,经常在使用中便会出现遥控故障。本刊2007年第一     

水库坝基帷幕灌浆施工技术及效果分析

帷幕灌浆作为地基处理方法之一,具有高效、低能、应用范围广等优点。文章就水库坝基帷幕灌浆施工技术及效果进行了分析,结合具体的工程实例,简述了帷幕灌浆的技术指标,详细阐述了帷幕灌浆的主要施工技术,并对灌浆的效果和质量作了系统的分析和评价,以期能为有关方面的需要提供参考借鉴。