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41.
文章以银-钯(Ag-Pd)合金+AgCl在HCl-H2O对热液中的溶解度测定为例,叙述了用合金作为实验初始物和同时测定合金组成的方法。本实验结果与前人在相同实验条件仅用不同方法所获得的结果比较后指出:①本实验中测得的银溶解度位于Zotov和Seward的研究结果之间;②从实验中测得把的溶解度,计算或的存在形式和控制把溶解度反应式的平衡常数与Gammons一致,所有这些结果都表明,用Ag-Pd合金+AgCl作为溶解度反应的初始物研究该合金组成的方法是可行的。该方法提出了控制体系氧逸度的新方法,为从实验上研究成矿元素在低温下的热液行为提供了可能。 相似文献
42.
缅甸铂族金属砂矿中的矿物种类 总被引:1,自引:0,他引:1
采用电子探针分析(EPMA),对缅甸铂族金属砂矿中的矿物种类进行了研究。物质组成研究查明:主要组合矿物是Pt、Ir、Os、Ru的自然元素和金属互化物。主要矿物是自然铂矿、铁铂合金、钌铱锇矿、等轴锇铱矿和铱锇矿。次要及稀有矿物是铂族金属的硫化物、砷化物、包括(Rh、Pd、Pt)2As和(Rh、Pd、Pt、Ni)2As两种陌生矿物、锑化物,以及含铂族元素的Fe、Ni、Cu硫化物。 相似文献
43.
Introduction As the result of economic development, metropolitans spring out in China. In metropolitans,the cities contact with each other through life line systems, the density of population is larger thanother areas, and social treasure in the unit area is much higher than other cities (GAO, 2003). Atthe same time, the risk of potential earthquake disaster in metropolitans increases greatly. One ofcharacters of metropolitan earthquake damage is that each city in the metropolitan will … 相似文献
44.
应用循环曲线法研究了在353 K的乙酰胺-尿素-NaBr熔体中Co2+在Cu电极上的电化学行为,获知Co2+电还原为金属Co是一步不可逆过程,测得a=0.25和Do=3.24×10-6cm2.s-1;而Ce(Ⅲ)、Sm(Ⅲ)不能单独还原为Ce和Sm,但可以被Co(Ⅱ)诱导而共沉积;由恒电位电解法得到非晶态的Ce-Sm-Co合金膜,合金膜中Ce和Sm的含量随电位、时间和浓度的变化而变化。其合金膜中Sm的最高质量分数可以达到47.98%,Ce的最高质量分数可以达到47.32%。 相似文献
45.
Marina A. Yudovskaya Vadim V. Distler Ilya V. Chaplygin Andrew V. Mokhov Nikolai V. Trubkin Sonya A. Gorbacheva 《Mineralium Deposita》2006,40(8):828-848
The distribution of gold in high-temperature fumarole gases of the Kudryavy volcano (Kurile Islands) was measured for gas, gas condensate, natural fumarolic sublimates, and precipitates in silica tubes from vents with outlet temperatures ranging from 380 to 870°C. Gold abundance in condensates ranges from 0.3 to 2.4 ppb, which is significantly lower than the abundances of transition metals. Gold contents in zoned precipitates from silica tubes increase gradually with a decrease in temperature to a maximum of 8 ppm in the oxychloride zone at a temperature of approximately 300°C. Total Au content in moderate-temperature sulfide and oxychloride zones is mainly a result of Au inclusions in the abundant Fe–Cu and Zn sulfide minerals as determined by instrumental neutron activation analysis. Most Au occurs as a Cu–Au–Ag triple alloy. Single grains of native gold and binary Au–Ag alloys were also identified among sublimates, but aggregates and crystals of Cu–Au–Ag alloy were found in all fumarolic fields, both in silica tube precipitates and in natural fumarolic crusts. Although the Au triple alloy is homogeneous on the scale of microns and has a composition close to (Cu,Ni,Zn)3(Au,Ag)2, transmission electron microscopy (TEM) shows that these alloy solid solutions consist of monocrystal domains of Au–Ag, Au–Cu, and possibly Cu2O. Gold occurs in oxide assemblages due to the decomposition of its halogenide complexes under high-temperature conditions (650–870°C). In lower temperature zones (<650°C), Au behavior is related to sulfur compounds whose evolution is strongly controlled by redox state. Other minerals that formed from gas transport and precipitation at Kudryavy volcano include garnet, aegirine, diopside, magnetite, anhydrite, molybdenite, multivalent molybdenum oxides (molybdite, tugarinovite, and ilsemannite), powellite, scheelite, wolframite, Na–K chlorides, pyrrhotite, wurtzite, greenockite, pyrite, galena, cubanite, rare native metals (including Fe, Cr, Mo, Sn, Ag, and Al), Cu–Zn–Fe–In sulfides, In-bearing Pb–Bi sulfosalts, cannizzarite, rheniite, cadmoindite, and kudriavite. Although most of these minerals are fine-grained, they are strongly idiomorphic with textures such as gas channels and lamellar, banded, skeletal, and dendrite-like crystals, characteristic of precipitation from a gas phase. The identified textures and mineral assemblages at Kudryavy volcano can be used to interpret geochemical origins of both ancient and modern ore deposits, particularly gold-rich porphyry and related epithermal systems. 相似文献
46.
47.
硅钙钡镁合金中钡钙镁的测定 总被引:5,自引:0,他引:5
采用HNO3-HF-HClO4分解试样,分别以硫酸钡重量法、EDTA容量法及原子吸收法测定了硅钙钡镁合金中的Ba、Ca、Mg,结果与硅钙钡合金标样的标准值相符。加标回收试验的回收率为99.00%~102.00%,样品5次测定的RSD小于1.19%。 相似文献
48.
A damper device based on shape memory alloy (SMA) wires is developed for structural control implementation. The design procedures of the SMA damper are presented. As a case study, eight such SMA dampers are installed in a frame structure to verify the effectiveness of the damper devices. Experimental results show that vibration decay of the SMA damper controlled frame is much faster than that of the uncontrolled frame. The finite‐element method is adopted to conduct the free and forced vibration analysis of the controlled and uncontrolled frame. The experimental and numerical results illustrate that the developed SMA dampers are very effective in reducing structural response and have great potential for use as efficient energy dissipation devices with the advantages of good control of force and no lifetime limits, etc. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
49.
PengGang FanJian LiLi TanJiaxiang 《中国地质大学学报(英文版)》2003,14(2):169-174
In this article, mechanics model of SMA center tension from damper is developed. According to the theory of Brinson constitutive model and thermodynamics first law, damper thermodynamics non-linear equation has been developed. Dynamics non-linear equation of frame structure under operation of SMA damper and its solution have been worked out; the software of seismic response analysis for frame structure and of damper characteristic analysis have been compiled with MATLAB software, andthe examples have been computed with it. The result indicates that SMA damper has obvious damp characteristics and it can provide with obvious restraint effect for seismic response of frame structure. Decreasing rate of displacement and velocity on top of frame structure reaches 50%-60%. The result is in accordance with other pundits experimentation results, which indicates that the above methods are correct and useful. 相似文献
50.