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991.
利用静电植绒技术,制成具有空气净化性能的活性炭纤维静电植绒制品.将植入绒毛量作为统一的评价标准,通过改变极板电压、极板距离以及植绒时间等3个工艺参数,分析其对单位面积植入绒毛量的影响.实验结果表明,单位面积植入绒毛量随着极板电压和植绒时间的增加而增加,随着极板距离的增加而减少. 相似文献
992.
993.
赵娟娟 《华北科技学院学报》2010,7(3):64-67
将酞菁铜颜料微胶囊应用到喷墨墨水中很好地解决了颜料在喷墨墨水中的分散稳定性。以具有良好环境效应的水为溶剂,调整控制酞菁铜颜料微胶囊的粒径、体系的粘度和表面张力,制备了微胶囊型酞菁铜颜料喷墨墨水,并用EPSON ME 200喷墨打印机进行性能测试。结果表明:微胶囊型酞菁铜颜料喷墨墨水中颜料粒径小于100nm,体系的粘度为1.2cP,表面张力为27.6mN/m,满足喷墨墨水的要求;微胶囊型酞菁铜颜料喷墨墨水的着色力、稳定性、耐热性和耐溶剂性接近进口墨水EPSON R210的标准,但耐光性较差。 相似文献
994.
发展了一种高效、简单的铜催化活泼烯烃羰基化成环合成吲哚酮的方法.以氯化亚铜为催化剂,二叔丁基过氧化物(DTBP)为氧化剂,丙酮为溶剂兼反应物,在100 ℃条件下与N-芳基丙烯酰胺类化合物发生自由基串联环化反应,高效地合成了一系列吲哚酮衍生物.探索不同温度、催化剂、溶剂等因素对反应的影响,并推导此环化反应的机理过程. 相似文献
995.
Aiming at recovering iron from high-iron-content copper slag, this article introduced a combination technology of deep reduction and magnetic beneficiation, investigated the iron recovery efficiency and optimized the technical conditions. When coke powder with 86wt% fixed carbon was used as a reductant, iron was successfully extracted from the copper slag. Under the optimized condition of the coke powder content of 14wt%, the calcium-to-silicon mass ratio (Ca/Si) of 0.2, the roasting temperature of 1300℃, the roasting time of 3 h, the grinding time of 20 min, and the magnetic field intensity of 61 kA·m?1, the iron recovery rate of the copper slag can reach 91.82%, and the extracted iron powder has an iron grade of 96.21%. With the characteristics of high iron grade and low impurity content, the extracted iron powder can be used as high-quality raw materials of weathering steel. 相似文献
996.
以大孔吸附树脂SD300为载体, 采用原位高锰酸钾氧化还原法将锰氧化物负载其上, 制备了新型锰氧化物?吸附树脂复合材料Mn-SD300, 并对其吸附水中Cd2+和Cu2+的性能进行了研究。TEM, XRD以及XPS的分析结果表明, 负载的锰氧化物以MnO2的形态存在。静态吸附实验结果表明Mn-SD300对Cd2+和Cu2+具有良好的吸附性能。吸附行为均符合准一级动力学模型(R2>0.99)和Langmuir吸附等温线模型(R2>0.99), 温度为303 K时, Mn-SD300对Cd2+和Cu2+的饱和吸附容量可分别达到76.92 mg/g和142.86 mg/g。在高浓度竞争离子Ca2+, Mg2+和Na+共存的情况下, Mn-SD300对Cd2+和Cu2+的吸附选择性要强于传统阳离子交换树脂D001。 相似文献
997.
为了研究和分析石墨纤维表面与孔隙的结构和分形性质,采用场发射扫描电子显微镜、电感耦合等离子体发射光谱仪、全自动物理吸附分析仪对其进行测试与表征.研究结果表明:石墨纤维以圆柱状存在,直径约为12~18 μm,表面较光滑,缺陷较少,有利于气体吸附;石墨纤维碳的质量分数约为95.86 %,还含有少量的N、H、O、S和微量的Ca、Fe、Mg、Si、Al等元素,生产过程中留下的孔道不多;石墨纤维的比表面积较大,其微孔体积占总孔体积的97.98 %,平均孔径在微孔区域,且孔径分布较窄,包含大量0.84 nm左右和少量1.21 nm左右的微孔,较丰富的微孔结构使其具有良好的吸附性能;石墨纤维的表面与孔隙具有较好的分形特性,分形维数分别为2.11和2.99,是一种有工业前景的吸附材料. 相似文献
998.
In the modeling of microsegregation, the partition coefficient is usually calculated using data from the equilibrium phase diagrams. The aim of this study was to experimentally and theoretically analyze the partition coefficient in binary aluminum-copper alloys. The samples were analyzed by differential thermal analysis (DTA), which were melted and quenched from different temperatures during solidification. The mass fraction and composition of phases were measured by image processing and scanning electron microscopy (SEM) equipped with an energy-dispersive X-ray spectroscopy (EDS) unit. These data were used to calculate as the experimental partition coefficients with four different methods. The experimental and equilibrium partition coefficients were used to model the concentration profile in the primary phase. The modeling results show that the profiles calculated by the experimental partition coefficients are more consistent with the experimental profiles, compared to those calculated using the equilibrium partition coefficients. 相似文献
999.
Improvements in the microstructure and fatigue behavior of pure copper using equal channel angular extrusion
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J. Nemati G. H. Majzoobi S. Sulaiman B. T. H. T. Baharudin M. A. Azmah Hanim 《矿物冶金与材料学报》2014,21(6):569-576
In this study, annealed pure copper was extruded using equal channel angular extrusion (ECAE) for a maximum of eight passes. The fatigue resistance of extruded specimens was evaluated for different passes and applied stresses using fatigue tests, fractography, and metallography. The mechanical properties of the extruded material were obtained at a tensile test velocity of 0.5 mm/min. It was found that the maximum increase in strength occurred after the 2nd pass. The total increase in ultimate strength after eight passes was 94%. The results of fatigue tests indicated that a significant improvement in fatigue life occurred after the 2nd pass. In subsequent passes, the fatigue life continued to improve but at a considerably lower rate. The improved fatigue life was dependent on the number of passes and applied stresses. For low stresses (or high-cycle fatigue), a maximum increase in fatigue resistance of approximately 500% was observed for the extruded material after eight passes, whereas a maximum fatigue resistance of 5000% was obtained for high-applied stresses (or low-cycle fatigue). Optical microscopic examinations revealed grain refinements in the range of 32 to 4 μm. A maximum increase in impact energy absorption of 100% was achieved after eight passes. Consistent results were obtained from fractography and metallography examinations of the extruded material during fatigue tests. 相似文献
1000.
A variety of Pd( Ⅱ )-catalyzed oxidative transformations ot allcenes with oxygen nucleophiles are catalyzed by PdXa(X=OAc, Cl, etc) with CuX.( n = 1 or 2) under O2. In the so-called Wacker catalyst of such,Pd(OAe)2 is less reactive compared to PdCl2. In an attempt to increase the reactivity of Pd(OAe)2, we have now found that tuning of Cu site with catechol gives an intriguing reactivity to Pd(OAc)2, which is unprecedented in the chemistry of palladium. 相似文献