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1.
星光宝石、猫眼宝石属于高档名贵宝石品种.文章着重介绍了星光宝石、猫眼宝石的矿物内部结构及其特殊光学效应,对两者的工艺设计、晶体定向以及加工工艺方面作了详细的阐述.研究认为,在加工此类宝石的过程中,应对其内部特殊结构及其光学效应要有全面的了解,并要熟练掌握晶体定向知识和工艺技巧,尽可能做到精心设计、谨慎作业,才能加工出完美的宝石来.  相似文献   

2.
本文笔者主要分析部分红宝石的填充材料及其充填工艺,并针对利用现代测试技术来分析充填红宝石的主要鉴别特征,与广大宝石爱好者作出技术交流:  相似文献   

3.
阐述了国内外水热法生长高档宝石晶体的历史与现状,介绍了桂林矿产地质研究院在水热法生长高档宝石方面的科研成果和技术水平,指出水热法合成晶体材料的发展方向是完善生长工艺、降低成本、占领市场和合成新型功能晶体、拓宽应用领域.  相似文献   

4.
拼合宝石目前在国内很少见,研究和开发拼合宝石具有较大的发展前景.以拼合宝石为研究对象,从拼合宝石的整体性、工艺、粘胶剂几方面作了试验研究,并提出拼合宝石的鉴别特征.  相似文献   

5.
阐述了北美宝石雕刻艺术风格的形成与其创造灵感的渊源,介绍了北美宝石艺术家的雕刻工艺趋势和其作品的创意特点.  相似文献   

6.
发光宝石是近期由我国的科学工作者依靠现代科学技术研制出的"现代夜明珠",在宝石界引起强烈反响.以庆隆夜光宝石为实例,介绍了发光宝石人工合成技术的发展状况、制作工艺和应用范围,同时分析了夜光宝石的发光原理以及影响夜光宝石的质量因素.  相似文献   

7.
对触媒在合成宝石级金刚石工艺中的作用机理进行了探讨,分析了触媒对合成宝石级金刚石晶体性质和晶体质量的影响,并提出了通过控制触媒获得高质量宝石级金刚石晶体的几点建议.  相似文献   

8.
Ali  N Ahmed  W 《电刷镀技术》2000,(1):44-47
论述了宝石膜和类宝石膜的独特和优异的性能以及其在工业中的应用这述表面宝石膜的涂覆原理、各种涂覆方法和设备,分析了当前各种沉积方法的优缺点。指出了为使宝石膜能充分发挥其巨大潜力而必须进一步研究解决的一些问题。  相似文献   

9.
根据国产六面顶液压机合成宝石级金刚石的合成块腔体内部过剩压减小及电阻变化的特点,使用天宏控制工程第三代操作系统检测六面顶压机设备的合成电流、合成电阻等参数重新编制宝石级大单晶合成工艺曲线.根据所设定的工艺曲线进行分阶段控制合成腔体内部的压力和温度,来稳定合成块内部金刚石的生长环境.研究发现合成宝石级金刚石前期10小时工...  相似文献   

10.
目前宝石唯一性鉴定比较通用的手段是借助宝石证书、腰棱编码和台面印记。而这些方式都存在着被仿冒的风险,在流通过程中降低了可信度。借助宝石本身的几何结构特征和光学效果进行唯一性鉴定,对于大批量宝石的流通和追溯具有重要意义。目前国内外这方面的专利比较少,主要包括美国Photoscribe公司的多个点光源照射宝石获取点状图案法、刘厚祥的宝石几何结构特征参数识别法、郑珂威的基于同态加密保护的宝石图像特征识别方法等。作者的专利将钻石唯一性识别和钻石明亮度定量分析相结合,具有识别效果好、视觉效果美妙、易于推广等优势。  相似文献   

11.
ONACCURACYOFANALYSISOFOFHYDROGEN1前言我公司目前应用的氢气纯度分析方法有两种,一种是爆炸反应法,另一种是焦性没食子酸吸收法。几年来,人们对两种分析方法的准确性曾有过褒贬不一的评论。这里我们也谈谈自己粗浅的观点。2爆炸法测定氢气纯度一定量的氢气样品与适量的空气之均匀混合物因反应后生成液体水而引起气体体积减少,减少的体积等于参加反应气体体积之和。其中l/3为氧气,2/3为氢气。根据氢气取样量和反应前后混气体体积之差,以及氢气在反应中的体积比例关系,可计算出样品的氢气纯度。计算公式式中:A一混…  相似文献   

12.
The different analytical methods proposed for the evaluation of gypsum have been subjected to an experimental test. A combination method, consisting of a fusion with KHCO3 and determination of CaO by KMnO4 titration, the SO3 by Andrews method of titration of BaCrO4 has been found to give very reliable results with the least consumption of time.  相似文献   

13.
A model is developed for the sedimentation from a suspension of two particle species of unequal densities and of different sizes. The composition and the thickness of various layers in the sediments are predicted using graphical and analytical methods. The model predictions were in excellent agreement with experimental results, when the particle size ratio was ≥ 108. When size ratio of the particles was 2.60 and 4.31 the agreement occurred in about 50 percent of the cases.  相似文献   

14.
A novel technique serves to monitor instantaneous rates of loss of a volatile solute from a suspended drop during drying. A highly sensitive electron capture detector is used to monitor concentrations of SF6 released into a flowing gas stream from a suspended, drying drop. Simultaneously, the appearance and morphological development of the drop are monitored with a video camera. This provides the wherewithal of relating instantaneous rates of loss of the volatile solute to particular events during the development of particle morphology.

Initial experiments have been carried out with drops of aqueous solutions of glucose, sucrose, maltodextrin and coffee extract. The results clearly display the onset of the volatiles-retentive selective diffusion phenomenon. There is also substantial loss of the volatile component later in the drying process, when the drops undergo repeated ex ansion, bursting and cratering due to the formation of internaf bubbles. These experiments appear to be the first quantitative demonstration of major losses accompanying changes in drop morphology.  相似文献   

15.
茶多酚提取方法进展   总被引:22,自引:0,他引:22  
葛宜掌  金红 《精细化工》1994,11(4):52-55
本文综述了国内外现有茶多酚提取方法的现状以及近期的研究进展,并对其优缺点进行了评价。这将有助于中低档茶的综合利用和茶多酚的进一步开发应用。  相似文献   

16.
几种针状焦性能对比   总被引:3,自引:1,他引:2  
针状焦分石油系和煤系两大类,这主要取决于针状焦的原料来源。在同一系列中由于原料不同和工艺条件不同 ,针状焦的各自性能也不相同。针状焦是生产超高功率石墨电极和高功率石墨电极的主要原料 ,针状焦的性能对石墨电极的质量有至关重要的影响。所以对针状焦性能以及其对石墨电极质量影响的研究十分必要的。以下是常用的几种进口针状焦和国产针状焦的性能对比。1原料性能分析对比原料试样包括4种针状焦 ,其中两种为进口针状焦:三菱针状焦和新日化针状焦;另两种为国产针状焦:鞍山针状焦和锦州针状焦。其中除锦州针状焦是石油系针状焦外…  相似文献   

17.
ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES   总被引:5,自引:0,他引:5  
Viscosity of Simple Soda-Silicate 500° to 1400°C Comparison of the results given by English with those of Washburn, Shelton and Libman, indicates a discrepancy in the absolute values of log10 viscosity amounting to 0.6, those of Washburn et al., being relatively too high. If correction for this is made, the isothermal curves of log10 viscosity as a function of soda content are smooth up to 50% Na2O, showing no inflection. The observations as a function of temperature T are all represented within accidental error by an equation of the type where all three constants vary regularly with the composition. Change of Viscosity of Glass (6SiO2, 2Na2O) due to Molecular Substitution of CaO, MgO and Al2O3 for Na2O The effect is clearly brought out by plotting (from the results of English) the change of log10η due to the substitution as a function of temperature. The curves each show a sharp bend at a temperature between 840° and 1050°C, which is designated the aggregation temperature Ta. If we divide these curves by the corresponding percentage substituted, we get curves for each oxide which are straight and parallel below the aggregation temperatures, the slopes (increase of change of log10η per 100°C) being −0.056 (CaO), −0.055 (MgO), −0.018 (A12O3) per per cent oxide substituted. For substitution of 1/2 molecule the slopes are −0.325 (CaO), −0.23 (MgO) and −0.18 (Al2O3) per 100°. At the aggregation temperature the change of log10η per per cent is a minimum, 0.03 to 0.06 for CaO, 0.12 for MgO, 0.07 for Al2O3. Evidence of Aggregation in Glasses, from viscosity Measurements The sharp bends in the plots of change of log10η due to substitution of an oxide for Na2O, suggest the beginning of molecular aggregation at these temperatures. These aggregation temperatures are close to the devitrification temperatures, but the effect on the viscosity curves cannot be due to actual devitrification since it does not change with time. Taking the aggregation temperatures as equal to devitrification temperatures, additional isotherms are roughly sketched into the equilibrium triangle of the system Na2O-CaO-SiO2. Change of Viscosity of Glass (4SiO2, 2Na2O) due to of Substitution of B2O3 for SiO2 The change of log10η (from the results of English) is plotted as a function of temperature, and also the change of log10η per per cent B2O3. The curves are more complex than for the substitution for Na2O.  相似文献   

18.
环氧树脂羟基值测定方法的研究   总被引:1,自引:0,他引:1  
利用乙酸酐、吡啶和浓硫酸混合的乙酰化试剂测定环氧树脂中羟基值含量的方法具有操作简便、滴定终点明显和分析结果误差小等优点。  相似文献   

19.
面对日益激烈的市场竞争,摩托车油箱外观质量越来越成为影响销售的因素之一。文章介绍了改进工艺后的油箱涂装,该涂装体系提高了油箱外观的丰满度,降低了油箱涂装的生产成本。  相似文献   

20.
本文评述了缩聚型聚酰亚胺的主要合成方法和近年来国际上在合成中所做的探索。  相似文献   

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