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11.
采用Gly—GlyOH,4,4'—联吡啶与Cu(NO_3)_2·H_2O在二次水溶液中反应,合成出以4,4'—bpy为中继基,Gly—Glyo为螯环新型双核铜配合物。经X射线单晶结构分析确定该配合物品体的化学结构式:[(H_2NCH_2CONHCH_2COO) Cu(OH) (C_(10)H_8N_2)Cu(OH) (H_2NCH_2CONHCH_2COO)]·9H_2O.晶体属于三斜晶系,P_空间群,晶胞参数a=1.1412nm,b=1.2298nm,C=1.4269nm,α=113.82°,β=101.91°,y=103.64°,V=1.6747nm~3,Z=2。衍射数据是在Nicolet XRD R3型四圆衍射仪上收集,结构参数经块矩阵最小二乘法精修后,最终一致性因子R值为0.068,RW值为0.057。 相似文献
12.
Three-dimensionally ordered long-range macroporous carbon structures were prepared using commercially available phenolic resin
by utilizing sacrificial colloidal silica crystalline arrays as templates that were subsequently removed by HF etching after
pyrolysis in an argon atmosphere. SEM, TEM, and BET were employed to characterize the morphology and the surface area of the
porous carbon structures. The pore size (150–1000 nm) and BET surface area, which reflect pore volume (298.6 m2/g (1.32 cm3/g) ∼ 93.7 m2/g (0.12 cm3/g)), of the macroporous carbon structures produced were approximately proportional to the size (150–1000 nm) of the sacrificial
silica sphere templates used (annealing temp. 550°C). The achieved 550 nm porous carbon structures were examined to function
as potential catalyst carriers and were successfully impregnated with Ag or Pt-Ru on their inner walls after borohydride reduction
at room temperature. In addition, porous carbon patterns were fabricated using the ‘micromolding in capillary’ technique,
which has potential applications in the microreaction technology. 相似文献
13.
水合肼生产中氧化反应的研究和应用 总被引:1,自引:1,他引:1
分析了尿素法生产水合肼的氧化反应历程及影响因素,改进了反应器,并找到了最佳的工艺控制条件:①控制n(尿素):n(次氯酸钠)=(1.05~1.10):1,各原料的消耗较低,总经济效益佳;②采用-5℃冷冻盐水移走尿素、次氯酸钠混合段内氯化反应放出的热量,控制物料混合终点温度在15~30℃;③采用列管式加热器,将氯化反应与水解反应在不同的设备中进行,水合肼的收率提高到83%~85%;④采用列管式加热器代替双夹套反应器,提高了加热强度,生产能力大,1套合成反应器可生产1万t/a80%的水合肼。 相似文献
14.
Based on controls of structural style and the position in coalbed methane(CBM)development,we used a method of curvatures to study its relations with CBM development parameters.We calculated structural curvatures of contours of the No.3coal seam floor of the Shanxi Formation in the Zaoyuan block of the Qinshui Basin and analyzed its relations with development parameters of coalbed methane wells.The results show that structural curvature is negatively related to coal reservoir pressure,while positively related to permeability.With an increase in structural curvature,the average production of coalbed methane wells increases at first and then decreases,reaching the highest production at 0.02 m-1 of structural curvature.Therefore,structural curvature can be an important index for potential evaluation of coalbed methane development and provide a basis for siting coalbed methane wells. 相似文献
15.
傅楚昉 《武汉冶金管理干部学院学报》2010,20(2):25-27
“彼得原理”告诉我们,要让合适的人做合适的事,应根据每个人个性心理特征的不同,安排与之相适应的事情,以利于工作效率及效能的提高。组织合适的人做适合的事,重视能力素质模型的应用,是管理工作者的应有之义。 相似文献
16.
17.
离心铸造高速钢轧辊铸造缺陷形成与控制技术研究 总被引:1,自引:1,他引:1
采用离心铸造方法制造高速钢轧辊工艺简单,操作方便,但易出现偏析、裂纹、气孔、缩孔及夹杂等缺陷,影响轧辊的力学性能和使用性能.采用稀土-钛复合变质处理改善合金的组织和性能,同时改进离心铸造工艺参数可以消除高速钢轧辊铸造缺陷,提高力学性能,改善使用效果. 相似文献
18.
The effect of reinforcement on the solidification of pure metal matrix composites (MMCs) was simulated using a two-dimensional solidification temperature field model by the finite element method. The concept of the character length was proposed to describe the size of reinforcement local heat influential zone in MMCs solidification according to the change of the morphologies of solid-liquid interface. The relationship between the character length and the geometrical conditions, the boundary condition and physical properties of the reinforcement were studied, respectively. The results show that the width of the unit and the cold boundary temperature have no effect on the character lengths but have effect on the distance between cold boundary and reinforcement (/) and the thermal parameters of the reinforcement. An experimental rule to predict the value of the character length was derived and applied. 相似文献
19.
Halloysite template, a ceramic substrate, is of a hollow cylindric structure, on which the fine Pd nanoparticles are uniformly formed by the reduction of palldate chloride to initiate electroless deposition. The electroless deposition of Ni is catalyzed by the Pd particles, which results in a uniform layer of Ni-P alloy on halloysite. The alloy is of a nanocrystalline structure, of which the average diameter is about 6 nm. After being heat-treated at 400 ℃, it contains both Ni and Ni12P5 crystal, meanwhile, the Ni crystal gets larger with an average size of 51.9 nm.The content of phosphorous in the Ni layer has a great influence on crystal structure. The metallized halloysite has a higher inherent coercive force, and a much lower saturation magnetization in its as-plated state, while after heattreatment, the inherent coercive force decreases drastically. These magnetic properties have great relationship with the superparamagnetism of Ni nanocrystalline and the stress anisotropy in Ni layer. 相似文献
20.
应用离心铸造方法:以Cr,Mo,V,Nb为主要合金元素,研制成功了CrMoWVNb白口铸铁轧辊,分析了合金元素在轧辊中的作用,指出在轧辊中加入适量稀土和钛可细化轧辊组织,改善轧辊性能,同时还分析了轧辊生产中裂纹产生的原因,提出了消除裂纹的措施,并应用于高速线材轧机预精轧机架,使用寿命达到高镍铬无限冷硬铁轧辊的4-5倍。 相似文献