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排序方式: 共有6983条查询结果,搜索用时 15 毫秒
81.
以氢氧化钠作为沉淀剂,对含砷废水进行选择性沉淀研究,考察了pH值、搅拌速度、温度等因素对砷、铁分离效果的影响,确定了合适的工艺条件:温度25℃,pH=13.5,搅拌速度500 r/min.此工艺条件下铁的回收率达到99.9%以上,实现了砷、铁的有效分离. 相似文献
82.
将以具有链状高分子结构的柠檬酸铋为模板和前体合成出本身具有抑菌活性的含铋纳米材料,并以此为载体,通过吸附、填充、化学结合等方法与药物小分子或抗生素形成复合材料.研究含铋纳米材料和小分子复合过程的相互作用.评价含铋纳米材料在复合前后对幽门螺杆菌生长的抑制活性的变化.初步研究在模拟生理条件下,纳米材料分解和释放药物的过程,为研究开发新的治疗消化性溃疡疾病的药物提供新的思路. 相似文献
83.
高砷铜精矿浸出液中因含砷较高存在砷害问题,砷回收利用具有重要的意义。研究针对某高砷硫化铜精矿除杂后的浸出液,探讨了以砷酸铜形式综合利用砷的热力学及工艺参数。绘制了Cu-As-H2O系电位-pH图,进行了砷酸铜制备工艺过程的热力学分析,对净化后的某高砷硫化铜精矿浸出液,以氨水为中和剂,当pH=5.0~8.0,温度80~90℃时,制得了CuAs2O4、C4H6As6Cu4O16、Cu5As2O10.5H2O、Cu5As4O15.9H2O、Cu2AsO4OH.3H2O及Cu2AsO4OH 6种不同结构的砷酸铜,沉砷后溶液中砷含量为9.11~35.82 mg/L。 相似文献
84.
LIU JunFeng & FENG YuJie State Key Laboratory of Urban Water Resource Environment Harbin Institute of Technology Harbin China 《中国科学E辑(英文版)》2009,(6)
SnO2 electrodes have many advantages in the degradation of toxic or bio-refractory organic wastewater,and SnO2 is a kind of anode material which has the potential to be widely used.Electrocatalytic effi-ciency and service life of Ti\SnO2 electrodes are key factors that can influence its applications.In order to enhance the electrocatalytic characteristics of Ti\SnO2 electrodes,a type of electrocatalytic electrode with nanocoating was prepared by direct current(DC)electrodeposition method and thermal oxidati... 相似文献
85.
Metallo-Supramolecular Polymerization: A Route to Easy-To-Process Organic/Inorganic Hybrid Materials
Mark Burnworth Daniel Knapton Stuart J. Rowan Christoph Weder 《Journal of Inorganic and Organometallic Polymers and Materials》2007,17(1):91-103
The self-assembly polymerization of ditopic macromolecules via metal–ligand binding is a facile route for the preparation
of metallo-supramolecular polymers (MSPs). We herein review our recent work focused on the synthesis and investigation of
metallo-supramolecular polymers based on 2,6-bis(1′-methylbenzimidazolyl)pyridine endcapped poly(p-phenylene ethynylene) and poly(p-xylene) macromonomers. These materials are readily solution-processable and display appreciable mechanical properties as
well as other attractive properties such as specific opto/electrical functions or high thermal stability. Our work illustrates
that metallosupramolecular polymerization offers an attractive approach to assemble high-molecular-weight macromolecules from
well-defined, easy to process precursors. Variation of the ditopic ligands and metal ions allows one to easily tailor the
desired properties.
This paper is dedicated to Professor Ian Manners and his scientific accomplishments. 相似文献
86.
87.
钯-银合金膜分离氢气的研究 总被引:1,自引:0,他引:1
采用厚为50μm的Pd/Ag(23)合金膜进行了氢气渗透系数的测定和H_2/N_2混和气分离的研究,得出温度、压力、膜厚、进料气流量、膜的预处理和再活化及膜表面中毒等因素对氢气渗透的影响。分离H_2/N_2混和气可获得高纯氢气。 相似文献
88.
A new hybrid polymer electrolyte system based on chemical‐covalent polyether and siloxane phases is designed and prepared via the sol–gel approach and epoxide crosslinking. FT‐IR, 13C solid‐state NMR, and thermal analysis (differential scanning calorimetry (DSC) and TGA) are used to characterize the structure of these hybrids. These hybrid films are immersed into the liquid electrolyte (1M LiClO4/propylene carbonate) to form plasticized polymer electrolytes. The effects of hybrid composition, liquid electrolyte content, and temperature on the ionic conductivity of hybrid electrolytes are investigated and discussed. DSC traces demonstrate the presence of two second‐order transitions for all the samples and show a significant change in the thermal events with the amount of absorbed LiClO4/PC content. TGA results indicate these hybrid networks with excellent thermal stability. The EDS‐0.5 sample with a 75 wt % liquid electrolyte exhibits the ionic conductivity of 5.3 × 10?3 S cm?1 at 95°C and 1.4 × 10?3 S cm?1 at 15°C, in which the film shows homogenous and good mechanical strength as well as good chemical stability. In the plot of ionic conductivity and composition for these hybrids containing 45 wt % liquid electrolyte, the conductivity shows a maximum value corresponding to the sample with the weight ratio of GPTMS/PEGDE of 0.1. These obtained results are correlated and used to interpret the ion conduction behavior within the hybrid networks. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1000–1007, 2006 相似文献
89.
The kinetics of leaching arsenic from Ni-Mo ore roasting dust was investigated. The effects including leaching temperature, particle size of the smelter dust, stirring speed, the coefficient β(the molar ratio of sodium chlorate to arsenic in the smelter dust) and the initial H+ concentration on leaching arsenic were studied. The results indicate that the leaching of arsenic increases sharply with the decrease of particle size. The orders of reaction with respect to H+ concentration and particle size are determinted to be 1.136 and 1.806, respectively. The leaching of arsenic reaches 99% under experimental conditions, the apparent activation energy is determined to be 11.157 kJ/mol, which is consistent with the values of activation energy for diffusion model The kinetics equation of leaching arsenic from the roasting dust could be expressed by a semi-empirical equation as 1-2/3η (1 -η)^2/3 = k0(c[H+])^1.136ro^-1.806 exp[(-11157 /RT)t]. 相似文献
90.
选取炭黑、谷壳灰、绢云母、蒙脱土、凹凸棒石和硅灰石等6种不同形态的无机填料,采用液态成型工艺,制备了无机填料/丁腈橡胶硫化胶,研究了无机填料对丁腈橡胶的力学性能、交联密度、耐燃料B性、耐油性、耐热老化性和微观形貌等特性的影响。结果表明:加入炭黑后,硫化胶的综合性能最佳;加入蒙脱土后,硫化胶的交联密度增至2.49×10^-4mol/cm3,三维交联程度增幅最大;加入凹凸棒石后,硫化胶在燃料B中质量变化率、体积变化率降至同比最低,对耐燃料B性能改善幅度最大;加入硅灰石后,硫化胶在油性环境中的质量、体积变化率、硬度变化最小,对耐油性改善最多;加入绢云母后,硫化胶在热空气氛围下质量变化率、体积变化率和硬度变化同比最小,对耐热老化性能改善幅度最大。 相似文献