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71.
探讨了无机化学实验中碱式碳酸铜制备的改进方法。采用CuS04和Na2CO,为原料进行制备,确定了最佳实验条件为nCuS04/nNa2C03=1:1,T=60℃,终点溶液pH=8.5,静置48h,反加(硫酸铜溶液加入到碳酸钠溶液)。通过元素分析、红外光谱分析、X—RD等手段确定了该方法制备出了高纯度的碱式碳酸铜。 相似文献
72.
张希贵 《黄石理工学院学报(人文社科版)》2006,23(1):105-106
作文是语文教学的最高表现形式。提高学生的作文水平,必须要求学生注重平时作文材料的积累,在个性、特色上做文章。 相似文献
73.
本文研究了在压缩八面体场中(D_4h群)Cu~(2+)的△值和ESR参数的关系,并作了Cu~(2+)的计算机模拟ESR波谱. 相似文献
74.
《文物保护研究》2013,58(1):20-3
AbstractSevere corrosion was found covering the brass beads on several beaded belts. The corrosion was a mixture of copper soaps and zinc soaps, and was so thick in some places that it completely buried the brass beads. One of these belts was chosen as a test case for cleaning. The details of the cleaning are described, as are the effects of the corrosion process on the beads and surrounding organic materials. Two supporting studies are also reported: tests of the solubility of the corrosion in a variety of organic solvents, including mixtures of ethanol and petroleum-based solvents; and tests of leather dressings and other coatings on brass, copper, and zinc coupons in various relative humidities (RH), to determine what values of RH could be recommended for storage. 相似文献
75.
《文物保护研究》2013,58(2):112-115
AbstractThe present work demonstrates by means of two practical examples the extreme importance of examination of cross sections of metal threads to obtain an overview of their structure and of the different materials employed in their manufacture. Problems that might be caused by disturbance of surface features during polishing were prevented by covering the sample before embedding with a layer of nickel, using electroless deposition. Results from scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX) showed that, although the mean chemical composition of both metal wires is the same, their metallurgical structure is completely different: one consisting of pure silver with inclusions of copper particles and the other a silver–copper alloy. 相似文献
76.
《文物保护研究》2013,58(2):97-106
AbstractThe Danish sculptor Anne Marie Carl-Nielsen (1863–1945) often prepared three-dimensional models in wax before producing her works of art. The Carl Nielsen Museum in Odense keeps a unique collection of around 200 of the artist's fragile wax models. In 2008 the entire collection was examined, documented, X-ray radiographed, photographed, and conserved. Analyses of five figurines by attenuated total reflectance-Fourier transform infrared spectroscopy, optical microscopy, and scanning electron microscopy-energy dispersive X-ray spectroscopy showed two different kinds of wax mixtures, one containing beeswax and potato or maize starch as filler, and the other consisting of gypsum, zinc stearate, and a greasy substance. During the examination a specific deterioration phenomenon was noticed in the areas where the wax models had been strengthened with internal metal armatures. A chemical reaction between the wax mixture and the copper containing armature has caused an intense greenish colouring of the wax as well as creating a soft and almost liquid consistency and formation of copper(II) carboxylate salts. Based on an original recipe from Anne Marie Carl-Nielsen, a replica of one of the wax mixtures was produced and examined with respect to its infrared spectrum and its modelling properties. 相似文献
77.
Mehul Jariwala S. Suvarna G. Kiran Kumar Alpa Amin A. C. Udas 《Indian journal of clinical biochemistry : IJCB》2014,29(2):181-188
A study of iron, zinc, copper and selenium concentration levels was carried out in three compartments namely, maternal serum (MS), colostrums and cord blood serum (CS) of healthy Indian mothers (n = 42) who delivered healthy normal neonates without any congenital anomalies at Bhabha Atomic Research Centre hospital, Mumbai. Fe, Zn, Cu in maternal serum, cord blood and colostrums were estimated by flame atomic absorption spectrometry while Se was determined by graphite furnace absorption spectrometry. It was seen that there was a significant difference in the level of trace elements in the three compartments. The average levels of Fe in the three compartments were 1,132 ± 519, 2,312 ± 789 and 1,183 ± 602 μg/L while Zn was 514 ± 149, 819 ± 224 and 7,148 ± 2,316 μg/L respectively. Mean Cu values were 1,614 ± 295, 301 ± 77 and 392 ± 174 μg/L respectively while Se values were 70 ± 15, 36 ± 10 and 23 ± 8 μg/L respectively. The results indicated a positive correlation of Fe and Zn concentrations in MS versus CS which were (r = 0.386), (r = 0.572) respectively and Fe levels in MS and colostrums (r = 0.235). A few inter element correlations were found within compartments. Zn and Se showed a negative correlation in both MS (r = −0.489) and colostrums (r = −0.258) while a positive inter correlation of Fe and Zn was seen in MS (r = 0.44) and in CS (r = 0.54). This study gave us an overview of the serum and colostrum values of mother and neonates in Indian population, data of which are scarce. 相似文献
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本文提出了由微控制器STM32为主控制核心,利用普通的PCB覆铜板设计和制作低功耗手写绘图输入设备,通过表笔与覆铜板接触进行电压信号采集,然后将采集到的信号经高精度仪表放大器AD620放大调理后再通过24位高精度AD转换器ADS1256转换为单片机能够处理的数字信号,最后在LCD屏上显示对应接触点的坐标位置。 相似文献
79.
本文研究区大地构造位置位于东昆仑南缝合带北侧,布喀达坂峰-阿尼玛卿山华力西期铜、钴、金(锑)、煤、蛇纹岩Ⅲ级成矿带上,属秦祁昆地层区的东昆仑南坡分区。研究区出露的地层总体北部广布第四系,南西部分布古近系古新统—始新统沱沱河组地层,中西部以二叠系上统布青山群马尔争组为主;受昆南深大断裂的影响,区域内褶皱构造和断裂构造发育,构造以北西西向断裂为主;岩浆岩主要为华力西期晚期基性-超基性、中酸性侵入岩多分布于研究区中东部,多呈岩株、岩基、岩脉状产出。研究区内圈定MCu1—MCu6六条铜矿化带,MAu1、MAu2两条金矿化带,其中MCu2、MCu3铜矿化带和MAu1、MAu2金矿化带规模及品位较好。通过对已有地质信息与典型矿床对比分析成矿条件,确定找矿类型、找矿方向和找矿远景。 相似文献
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