显色法测定环境样品中的纳米二氧化钛

水环境中纳米二氧化钛分析方法的建立是研究其环境行为的基础.以钛离子与H2O2的显色反应为基础,建立了用分光光度计测定含纳米二氧化钛水样、鱼样的方法.该方法简便可行,不需要复杂仪器设备,测定结果与ICP-AES测定方法相比无显著差异.     

传热系数随温度线性变化的亚临界化学放热系统热安全性分析

引入化学放热系统平衡域和热安全裕度的概念与定义来评价具有潜在危险性的亚临界化学放热系统的安全性问题.分析了均温系统下传热系数随温度呈线性变化的系统的平衡域,进而提出了热安全裕度值L的定量计算并阐明了利用曲线拟合的方法计算L值.使用了Matlab软件绘出系统在3个约束参数约束的条件下ψ-ε-a的三维图形与给定系统(a为常数)时ψ-ε的二维图形,并在结合图形的基础上引入实例来评价该系统的热安全性.     

Treatment of pharmaceutical wastewater containing recalcitrant compounds in a Fenton-coagulation process

The advanced treatment using integrated Fenton＇s reaction and coagulation process was investigated in this study. Before the advancement, the pharmaceutical wastewater containing lincomycin hydrochloride was pretreated by UASB （upflow anaerobic sludge bed） and a SBR （sequencing batch reactor） process. The residual recalcitrant compounds, measured by gas chromatographymass spectrometry （GC-MS）, mainly consisted of alcohols, phenols, and nitrogenous and sulfur compounds. The experimental results indicated that when the Fenton＇s reaction was conducted at pH=3.0, H2O2CODOcr=0.27, H2O2/Fe^2＋=3：1 and 30 min of reaction time, and the coagulation process operated at a sulfate aluminum concentration of 800 mg/L and pH value of 5.0, the color and COD in the wastewater decreased by 94% and 73%, respectively; with a finale COD concentration of 267 mg/L and color level of 40 units, meeting the secondary standard of GB8978-1996 for industrial wastewater.     

Photo-degradation of Acid-red 3B dye catalyzed by TiO2 nanotubes

Introduction A s one kind of novel functional m aterial, TiO 2 nanotube has been found potential applications in solar cell (B arbe et al., 1997), sem iconductor device (V inodgopal et al., 1993) and catalyst supports (Idakiev et al., 2005) etc. Since K a…     

异丙醇与丙酸酐酯化反应的安全控制条件

针对异丙醇与丙酸酐酯化合成丙酸异丙酯工艺的反应失控危险性,利用泄放尺寸实验仪(VSP2)研究了其反应的放热特性,选择自催化模式模拟得到了反应动力学参数,并与实验数据进行了对比验证;利用得到动力学模型,模拟了该工艺在半间歇模式、反应温度为70℃时,中试规模(＞ 100L)条件下的反应特点,分析了反应失控的危险性,并针对加料程序进行了优化设计,得到最佳控制方法.     

Handgrip and Box Tilting Strategies in Handling: Effect on Stability and Trunk and Knee Efforts

The purpose of this study was to evaluate the effect of four handgrip/box tilting strategies (right, left, backward, and no tilt of the box) on trunk and knee efforts, body posture, and the stability of 14 participants with limited experience in handling. The tasks consisted of transferring a low-lying box placed in front of the participant to a shelf of the same height at the participant’s left. It was hypothesized that tilting the box could reduce trunk and knee efforts as well as body asymmetry and improve stability. A tridimensional dynamic rigid body model was used to estimate the triaxial net muscular moment magnitudes at the trunk (L5/SI) and at the knees. An approach to quantify the participants’ dynamic stability was also included. Finally, five angles were computed to characterize body asymmetries. The results showed that tilting the box affected specific trunk efforts, but did not succeed in reducing trunk asymmetric efforts. However, the tilts were executed in a single direction, and it may be possible that combined tilts of the box could help reduce trunk asymmetric efforts. Tilting the box had little effect on knee loadings, and the left tilt strategy reduced participants’ stability. This study showed the importance of considering the position of the box when assessing the risks encountered in asymmetrical handling.     

苯胺重氮化-席曼反应热危险性的理论研究

为研究苯胺重氮化-席曼反应的热危险性,采用Gaussian98软件,运用密度泛函理论(DFT)B3LYP,在6-31G(D)基组水平上,研究气相条件下重氮化-席曼反应的反应过程及微观机理,得到反应路径以及反应物、中间体、过渡态、产物全优化几何构型,探讨结构与性能的关系,解释重氮化-席曼反应的历程。通过热力学和动力学计算,获得标准热力学函数,分析反应的热危险性。理论计算结果表明:苯胺重氮化-席曼反应是剧烈的放热反应,这与重氮化反应剧烈以及重氮盐的热不稳定性的试验结果相吻合。     

金属-有机框架材料去除水中重金属Cr(Ⅵ)的研究进展

金属-有机框架材料（MOFs）作为新兴的有机-无机杂化材料,兼有稳定性好、多孔、比表面积大等优点,能高效去除水中的重金属Cr（Ⅵ）。本文概括了常用的Cr（Ⅵ）去除方法,重点综述了基于不同金属的MOFs应用于Cr（Ⅵ）吸附和还原转化的影响因素和去除机理,并阐述了MOFs在去除水中Cr（Ⅵ）领域的应用价值及面临的挑战。指出,应通过后修饰、多组分混合等方法进一步提高MOFs的应用潜力。     

人机界面在大型除尘系统控制中的应用

介绍了人机界面在大型脉冲袋式除尘系统控制中的一个应用实例,从实际使用情况看,人机界面在大型脉冲袋式除尘系统控制中的应用是成功的。     

异丙草胺在水溶液中的光解动力学

常温条件下,用400W高压汞灯和太阳光分别照射处理异丙草胺水溶液,考察光照和初始浓度对异丙草胺在水溶液中光降解的影响研究表明,太阳光照射下,异丙草胺的光解反应符合一级动力学规律,降解速率相对很小,在石英试管中1h的光解率只有5.5%;汞灯照射条件下异丙草胺的光解过程可用双室降解模式来描述,1h时的光解率可达80.9%;异丙草胺的初始浓度越大,其光解率越小,降解产物的生成影响异丙草胺本身的光解进程.运用GC-MS技术鉴定出异丙草胺的主要光解产物有6种,光解过程中苯环保持完好,并推测了异丙草胺的光解反应机理.