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31.
以阳离子染料可染改性涤纶丝与普通涤纶丝混纺(或交织)织物为研究对象,探讨碱剂。促进剂、减量温度及时间等因素对减量率的影响以及不同减量工艺经阳离子染料染色对织物闪色效果的影响。研究表明在保证一定减量率的基础上,染色后织物具有一定的闪色效果。  相似文献   
32.
为解决日本旭硝子公司AZM—F2电解槽在实际运行中出现的阴极部件易损、价高的问题,北京化工机械广研制开发可替代AZM—F2的国产单极式离子膜电解槽(MMC)。MMC系列单极式离子膜电解槽可与AZM—F2整体互换,活性阴极选用优质316L不锈钢,阴阳极采用对称结构,阴极导电面积是AZM—F2电解槽的4.3倍。MMC系列单极式离子膜电解槽投入运行后,电解槽运行平稳,槽电压等主要技术指标基本可达到AZM—F2型电解槽水平。  相似文献   
33.
In this study electrochemical performance of Al and some of its alloys (Al-Zn, Al-Mg and Al-Mn) anodes vs MnO2 cathode were carried out in alkaline solution. The results show that the Al-Zn alloy anode has the best cell capacity among the other alloys. Cell capacity values go in the order Al-Zn>Al-Mg>Al>Al-Mn. This result is probably related to the nature of passive films formed on the surface of the alloys which examined by scanning electron microscopy (SEM). SEM morphologies of Al and its alloys showed coarse grains of passive films formed on the surface of these anode materials while Al-Mn morphology shows a needle-like structure.Electrolytic manganese dioxide (EMD) produced by electrodepositing on platinum anode from liquor resulting from reduction of low grade pyrolusite ore (β-MnO2) by sulfur slag was characterized as cathode in alkaline Zn-MnO2 batteries. Ore produced sample (EMD1) was performed well in comparison with EMD standard (EMD2) (commercial battery grade electrolytic manganese dioxide, TOSOH-Hellas GH-S). SEM morphology of Zn anode after cell reaction was carried out and showed that Zn anode has fine grains of passive film on its surface.  相似文献   
34.
碱性单细胞凝胶电泳预测肿瘤细胞内在放射敏感性研究   总被引:3,自引:0,他引:3  
应用克隆形成法和碱性单细胞凝胶电泳技术检测辐射诱导的人红白血病细胞株K562、人结肠腺癌细胞株LS-T-117和鼠胶质瘤细胞株C6的初始DNA单链断裂数及单链断裂后的修复与细胞内在放射敏感性之间的关系。结果表明,3种细胞系的放射敏感性依次为K562>LS-T-117>C6;3种细胞系的DNA迁移距离都随着照射剂量的增加而增大,呈良好的剂量-效应关系。在相同剂量下,辐射诱导的DNA单链的初始断裂数目也依次为K562>LS-T-117>C6;3种细胞系经10Gy X射线照射并在PBS中培养不同时间后DNA迁移距离都有较大幅度的下降,但下降幅度依次为C6>LS-T-117>K562,在相同剂量下辐射诱导的DNA单链断裂后的修复能力也依次为C6>LS-T-117> K562。结果显示,辐射诱导的DNA单链断裂及修复与细胞内在放射敏感性有很好的相关性,可用于人体肿瘤细胞内在放射敏感性的预测。  相似文献   
35.
碱性锌锰电池阴极混合物研究   总被引:1,自引:1,他引:1  
本文研究了碱性锌锰电池阴极混合物含水量、成型密度、锰碳配比等技术参数对电池内阻、电性能及工业化生产的影响;初步探讨和分析了阴极参数与电池电性能间内在联系的一般规律和原理;介绍了几种简易测试方法。  相似文献   
36.
Anion exchange membranes (AEMs) are important energy conversion device for fuel cell applications, where the overall redox reaction happened. Both alkaline stability and ionic conductivity should be considered in the long-term use of fuel cells. In this work, imidazole functionalized polyvinyl alcohol was designed as the functional macromolecular crosslinking agent to fabricate crosslinked AEMs with brominated poly(phenylene oxide) matrix. Benefitting from the macromolecular crosslinked structure, the membranes displayed enhanced ionic conductivity and alkaline stability at elevated temperature. Moreover, membrane with ion exchange capacity of 1.54 mmol/g displayed ionic conductivity of 78.8 mS/cm at 80 °C, and the conductivity could maintain 75% of the initial value after immersion in 1 M NaOH solution at 80 °C for 1000 h. Moreover, a peak power density of 105 mW/cm2 was achieved when the assembled single cell with c-91 was operated at 60 °C. These results indicated that the construction of macromolecular crosslinked AEMs have great potential in the practical application of anion exchange membranes fuel cells.  相似文献   
37.
A simple and rapid non-chromatographic method was developed to determine methylmercury (MeHg) and inorganic mercury (iHg) levels in muscles tissues of 10 freshwater fish species. The MeHg and iHg were determined by cold vapour atomic absorption spectrometry after alkaline wet digestion of samples. The digested samples were reduced sequentially with stannous chloride and sodium tetrahydroborate for iHg and MeHg, respectively. Parameters such as carrier gas flow rate (argon), volume of oxidizing and potassium persulphate solutions were investigated in detail. The accuracy of the technique was evaluated by using certified reference material (DORM-2) and spiking the both Hg species in muscles tissue of a fish. The limits of detection were 0.117 and 0.133 μg kg−1 for MeHg and iHg, respectively. The concentrations of MeHg and iHg in muscles tissues of ten fish species were found in the range of (28.4–56.3) and (3.01–8.11) μg kg−1, respectively.  相似文献   
38.
The different methods for the generation of hydrogen are well known, as well as their applications, advantages and complications for their use. Every day it is essential to replace fossil fuels, so it is necessary to improve and take advantage of the different devices that we already have. The alkaline electrolyser is one of the best options, due to the simplicity of its components and its simple assembling; it is a relatively inexpensive device for the production of hydrogen. In this article, three different alkaline electrolyser stacks are presented, ECH-001 model. The difference between them lies in the fact that the configuration of the electrode changes with the number of drill holes. This has the purpose of optimizing the maximum productivity of the oxyhydrogen gas (OH2G) with respect to input power and the performance with different operation parameters, like the number of serial plates, geometry and the distance between them. The performance curves of parallel and serial arrangements are shown. The performance of a DEKTM diesel engine (monocylinder of 406 cc) with and without OH2G was evaluated, with flows of one, two and three sL min-1. Tests for CO, CO2, HC and NOx emissions were measured using the exhaust gas analyzer and varying the engine speed. The results show that the electrolyser assembly with four holes electrodes achieved the best performance with an OH2G productivity of 2 sL min-1 when using; 7 serial plates at the anode (which is called arrangement 1, 5–10), 3 mm gap and a 5% solution of NaOH. The results also shows a 14% reduction in fuel consumption, 22% reduction in HC, 23% reduction in CO, 7% reduction in CO2 and 15.5% NOx reduction with 2 sL min-1 of OH2G all this for 2500 rpm. The obtained results show a great advantage for the use of dual combustion with the diesel-hydrogen combination.  相似文献   
39.
Hydrogen evolution reaction (HER) in alkaline conditions usually requires a higher overpotential compared with acidic conditions due to the extra energy barrier originating from the additional water dissociation step. In this work, the theoretical calculation has confirmed that this challenge can be solved by the bimetallic synergic effect on binary transition metal catalysts. We report a simple method to synthesize NiMoP2 nanowires with (100) plane which can precisely expose Ni and Mo atom. The synthesized NiMoP2 nanowires exhibit a small overpotential of 87 mV to reach 10 mA cm−2 with a low Tafel slope of 66 mV dec−1 and long-term stability in alkaline solutions.  相似文献   
40.
Burnt-on protein residues on the surfaces of the utensils used in dairy and meat processing industries possess a major challenge, where routine cleaning operations involve the use of hot alkali and/or acid, detergent washes followed by heat or chemical sanitization. These conventional cleaning approaches are neither economical nor eco-friendly. An economic enzymatic approach using alkaline protease isolated from Bacillus pseudofirmus strain SVB1 is envisaged. The efficiency of the alkaline protease (crude extract and partially purified enzyme) in removing burnt-on protein residues from solid surface was monitored by three-dimensional atomic force microscopy and protein quantification methods. In addition, the efficiency was also compared with that of the commercially available alkaline proteases. Crude alkaline protease obtained from SVB1 removed casein, dairy effluent, abattoir effluent and poultry effluents from the model solid surface efficiently. Results showed that the crude enzyme significantly removed casein when compared to the commercially available alkaline proteases. After this enzymatic cleaning and subsequent treatment, no residual enzyme activity was detected.  相似文献   
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