Experimental Study of Producing High Pureand Ultra Fine ZnO Powder by Vacuum Ejector

ＥｘｐｅｒｉｍｅｎｔａｌＳｔｕｄｙｏｆＰｒｏｄｕｃｉｎｇＨｉｇｈＰｕｒｅａｎｄＵｌｔｒａＦｉｎｅＺｎＯＰｏｗｄｅｒｂｙＶａｃｕｕｍＥｊｅｃｔｏｒ①ＷａｎｇＨｕａ（ＤｅｐａｒｔｍｅｎｔｏｆＭｅｔａｌｕｒｇｙ,ＫｕｎｍｉｎｇＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉ...     

统计与规则相融合的领域术语抽取算法

中文领域术语自动抽取是中文信息处理中的一项基础性课题,并在自然语言生成、信息检索、文本摘要等领域中有广泛的应用。针对领域术语抽取问题,采用基于规则和多种统计策略相融合的方法,从词语度和领域度两个角度出发,提出一种领域术语的抽取算法并构建出相应的抽取系统。系统流程包括基于左右信息熵扩展的候选领域术语获取、基于词性搭配规则与边界信息出现概率知识库相结合的词语度筛选策略以及基于词频-逆文档频率(TF?IDF)的领域度筛选策略。运用此算法不但能抽取出领域的常见用词,还可以挖掘出领域新词。实验结果显示,基于如上方法构建的领域术语抽取系统的准确率为84.33%,所提方法能够有效支持中文领域术语的自动抽取。     

Accumulation of arsenic and nutrients by castor bean plants grown on an As-enriched nutrient solution

Phytoextraction is a remediation technique that consists in using plants to remove contaminants from soils and water. This study evaluated arsenic (As) accumulation in Castor bean (Ricinus communis cv. Guarany) grown in nutrient solution in order to assess its phytoextraction ability. Castor bean plants were grown under greenhouse conditions in pots containing a nutrient solution amended with increasing doses of As (0, 10, 50, 100, 250, 500 and 5000 μg L⁻¹) in a completely randomized design with four replications. Shoot and roots dry matter production as well as arsenic and nutrient tissue concentrations were measured at the end of the experiment. The results showed that increasing As concentration in nutrient solution caused a decrease in shoot and root biomass but did not result in severe toxicity symptoms in castor bean growing under a range of As concentration from 0 to 5000 μg L⁻¹. The As doses tested did not affect the accumulation of nutrients by castor bean. Although castor bean did not pose characteristics of a plant suitable for commercial phytoextraction, it could be useful for revegetation of As-contaminated areas while providing an additional income by oil production.     

用UASB-TF法处理某乳品厂废水

利用UASB-TF法处理某乳品厂废水,出水达到GB8978-1996中的Ⅰ级排放标准.该法处理乳品废水具有投资低、运行成本低、污染物去除率高、操作方便稳定的特点.在进水浓度1000 mgCOD/L时,出水浓度可以降到60-80 mgCOD/L,UASB的水力停留时间12h,TF体积负荷0.4kgCOD/(m3.d),水力停留时间4h,出水回用于冷冻机冷却水,直接运行成本0.30元/m3.     

Spatial configuration of extracellular polymeric substances of Bacillus megaterium TF10 in aqueous solution

Configuration of extracellular polymeric substances (EPS) excreted by microorganisms is related greatly to the inherent properties of EPS, and has a significant effect on the physicochemical characteristics of microbial aggregates, such as activated sludge for wastewater treatment, as well as their interaction with other substances in aqueous systems. In this work, the spatial configuration of microbial EPS is characterized using laser light scattering (LLS) technique, with EPS extracted from Bacillus megaterium TF10 as an example. The combined utilization of static light scanning (SLS) and dynamic light scanning (DLS) offers an effective avenue to explore the EPS configuration in aqueous solution, thus enables a better understanding about the physicochemical properties of EPS. The results show that EPS exist in the form of colloids in neutral aqueous solution (pH 7.0) and that their shape is random coil with incompletely extending chains. The attraction interaction between EPS colloids is related with the high flocculability of B. megaterium TF10. The cryo-electron microscopy image further confirms the spherical shape of EPS colloids. The LLS approach offers a powerful and convenient tool for characterizing microbial EPS configuration and understanding their behaviors in biological wastewater treatment systems.     

基于Android平台的安全TF卡设计

安全TF卡是一款便于携带、支持公钥基础设施(PKI)的身份认证产品,它同时具有安全认证和存储的功能,在移动终端、手机银行、数字版权保护方面有着广泛的应用前景。文中提出了一种基于安全芯片的安全TF卡设计方法,简要介绍了TF卡的系统设计框架和程序开发流程,并针对Android平台,创新性地采用文件读写的方式完成上位机和TF主控制器之间的通信,通过优化通信协议大大提升了数据传输的速率和稳定性,最后介绍了利用JNI技术进行Android演示程序开发的要点。     

Separation and Recovery of Silver(I) Ions from Base Metal Ions by Thiourea- or Urea-Formaldehyde Chelating Resin

Abstract

In the present work, thiourea-formaldehyde (TF) and urea-formaldehyde (UF) chelating resins have been synthesized and they have been used in the adsorptions of Ag(I), Cu(II), and Zn(II) metal ions by batch and column methods. The effect of initial acidity of Ag(I) solution and the adsorption capacities of TF and UF resins by batch method and the separation of Ag(I) ions from Cu(II) and Zn(II) base metal ions by the column method were examined experimentally. The adsorption capacities of TF and UF resins were found as 58.14 and 47.39 mg Ag(I)/g by batch method and 30.7 and 4.66 mg Ag(I)/g, 0.80 and 0.121 mg Cu(II)/g, and under 0.002 mg Zn(II)/g by the column method, respectively. It was found that Ag(I) ions showed higher affinity towards TF resin than UF resin, compared with Cu(II) or Zn(II) ions, and Ag(I) could be separated more effectively by TF resin from Cu(II)and Zn(II) ions.     

转铁蛋白的研究进展

转铁蛋白（Transferrin,TRF,TF,又称为铁传递蛋白、血清运铁蛋白、运铁蛋白、嗜铁蛋白、铁糖蛋白）是一种重要的β-球蛋白,是脊椎动物体内铁的运输者。1945年,Holmberg和Laurell首次在人血清中发现了这种非血红素结合铁的转铁蛋白,此后人们又在哺乳动物以及鱼类、两栖类及爬行类的血清中分别发现了转铁蛋白的存在。由于在抗菌、杀菌以及在肿瘤和癌症防治等方面的突出作用,转铁蛋白在医药界已越来越受到人们的重视并开展了转铁蛋白作为药物载体的大量研究。     

MPD1202／TF1202可直接驱动100A以内GTR模块的基极厚膜驱动器集成电路

介绍了MPD1202/TF1202的引脚排列、各引脚的名称、功能和用法,讨论并分析了其主要设计特点和参数以及内部结构、工作原理,进而探讨了其应用技术.     

1500W高频激励CO_2激光器的研究

讨论了高频放电激励ＣＯ２激光器的基本机理，报道了最新研制成功的高频激励横流ＣＯ２激光器的基本结构、技术特点和实验结果，该激光器低阶模输出为１．５ｋＷ，光束发散角小于２ｍｒａｄ。