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61.
箭猪坡矿床是丹池成矿带南端的一个以铅锌锑为主的矿床,随着2012-2014年在箭猪坡矿床钻孔中石英脉型锡矿体的首次发现,打开了箭猪坡矿床新的找矿空间。新发现的锡矿体矿石矿物组合类型主要为锡石+闪锌矿+脆硫锑铅矿+黄铁矿+石英及锡石+脆硫锑铅矿+石英+方解石。箭猪坡矿床锡石呈自形-半自形粒状,锡石粒径多在0.1~0.2mm,少数0.02~0.05mm,分布在含硫化物的石英脉裂隙中。物相分析显示箭猪坡矿床锡主要赋存在锡石中,锡石物相占83.33%~100%。阴极发光(CL)图像显示箭猪坡矿床中的锡石经历了两期结晶作用:早期锡石(Ⅰ)和晚期锡石(Ⅱ),早期锡石CL荧光亮度较小,呈暗灰色至黑色;晚期CL荧光亮度较大,呈白色至浅灰色。锡石单矿物SnO2含量91.623%~96.288%,平均94.03%,杂质主要有Fe、W、In等,其中FeO含量0.02%~0.52%,WO3含量多在0.02~1.34%,In2O3含量在0.476%~0.954%,Sn与FeO、In2O3呈负相关,锡石中FeO、WO3、Ta2O5、Nb2O5、MnO含量指示箭猪坡锡形成于中低-中温热液环境,成矿热液来源于高度分异演化的花岗质岩浆。通过与大厂矿田西矿带上部脉状锡矿体的类比分析,具有相似的成矿条件及矿物组合,推测所揭露到的脉状锡矿(化)体相当于西矿带上部脉状锡矿(化)体,而下部的网脉状、似层状锡矿体尚未揭露到,由此预测箭猪坡矿床深部找矿空间及找矿潜力大。 相似文献
62.
以二氧化硅为硬模板,采用碳化和硫化工艺制备出具有三维碗状结构的CoS_2/C复合材料.利用XRD,Raman和XPS研究了所制备材料的相组成,晶体结构,元素组成和价态.利用SEM和TEM对其微观形貌进行了表征,并采用电化学工作站分析了CoS_2/C作为超级电容器电极材料的电化学性能.结果表明:三维碗状结构CoS_2/C复合材料具有优良的电化学性能,在1 A/g的电流密度下比容量可以达到466 F/g.将CoS_2/C和N-rGO分别作为正极和负极组装的水系非对称超级电容器器件的电压窗口可以拓宽到1.6 V.该器件在0.5 A/g的电流密度下能量密度可以达到13.6 wh/kg,功率密度达到374.5 w/kg.在3 A/g的电流密度下经过5000次循环充放电后容量保持率达到了87%. 相似文献
63.
针对列车车轮多边形磨耗问题广泛存在于轨道交通运输领域,会导致车辆/轨道系统产生高频的振动冲击,严重影响车辆和轨道系统零部件的使用寿命,危及行车安全这一问题,调查了大量车轮的多边形磨耗情况并进行统计分析,掌握了高速列车车轮多边形磨耗问题的现状和特点。以18~20阶多边形磨耗车辆为例,通过理论研究和试验分析(试验分析包括车辆系统振动特性测试和转向架模态特性测试),对车轮多边形磨耗的根本原因及诱导因素进行研究。研究发现,轮轨系统在580 Hz频率附近存在固有模态是导致车辆发生18~20阶多边形磨耗的根本原因,轮轨表面的各种不平顺能激发或者加剧轮轨系统在580 Hz频率附近的模态共振,从而诱发车轮多边形磨耗的产生。该结果可为高速列车车轮多边形磨耗问题的防止和进一步研究提供参考。 相似文献
64.
65.
Liu Dejia Guo Rui Hu Yong Shen Mingxue Tang Yanchuan Zhao Longzhi Li Deying Wang Xiangjie 《Metals and Materials International》2020,26(6):854-866
Metals and Materials International - High-entropy alloys having excellent properties are particularly suitable for the application as the filler metals in welding. In the present study,... 相似文献
66.
目前微孔端面机械密封采用的几何参数繁多,缺乏明确物理意义。为找出跨孔型的共性几何参数,基于Fluent多相流空化模型,针对矩形孔、菱形孔、椭圆孔端面机械密封,建立密封间隙流体的三维数值计算模型,计算得到144条开启力数据;在分析开启力和几何尺寸之间的关系、额外开启力产生机制的基础上,提出等效长度和等效宽度2个具有物理意义的几何参数;采用灰色关联度分析法,分析和验证等效长度、等效宽度、方向角、面积比对开启力的影响,发现4个因素对3种微孔密封的间隙流体开启力都有影响,但等效长度与等效宽度的影响较方向角、面积比大。 相似文献
67.
68.
Cheng-Feng Yue Shi-Jei Huang Jhewn-Kuang Chen Hsien-Tsung Li Kam-Shau Chan 《Metals and Materials International》2018,24(2):307-313
The effects of an addition of 0–2 wt% Nd on thermal stability of 0–3 wt% Ca-containing modified AZ71 magnesium alloys was investigated. The ignition temperature was found to increase from that of AZ71, 574, to 825 °C with the addition of 0.5 wt% Ca and 1 wt% Nd. The ignition temperature was further increased to 1114 °C when 3 wt% Ca was added. The Ca- and Nd-added AZ71 was isothermally maintained at a temperature of 500 °C in air for 12 h. The MgO–CaO–Nd2O3 formed on the surface to improve the thermal stability of the AZ71–xCa–yNd alloys. While both the tensile strength and ductility decreased with the Ca concentration in the alloy, an addition of 1 wt% Nd was found able to alleviate the degradation effects of Ca on the tensile strength and ductility at 170 °C. Both solid solution formation and precipitation strengthening contributed to the increase in toughness. AZ71 containing 0.5–2 wt% Ca and 1 wt% Nd provides the optimum combination of ignition resistance and mechanical properties. 相似文献
69.
Wang Zhen Hu Zhenbiao Suo Tao Zhou Fenghua Li Yulong Muhammad Zakir Sheikh Wang Xiang Wang Yinmao 《Ceramics International》2018,44(10):11239-11256
Quasi-static and dynamic three-point-bending experiments were conducted on both annealed and chemically strengthened aluminosilicate glass scratched by different normal loads. Scratched areas were observed by optical microscope and atomic force microscope. Chemically strengthened glass shows better resistance to surface scratch. These dynamic experiments were carried out using a modified Split Hopkinson Pressure Bar (SHPB) device and a pulse-shaping technique was used to keep constant loading speed to the specimens. In tests, high-speed photography was also used to observe the failure process of the specimens. The test results showed that the flexural strength of aluminosilicate glass (AG) strongly depends on the applied loading speed. Compared with its annealed counterpart, the chemically strengthened glass (CSG) showed higher flexural strength to both static and dynamic loadings. Moreover, the three-point bending experiments were conducted on scratched AG and CSG specimens and decrease of 20–40% in flexural strength was observed. The fractography analysis showed that in dynamic loading conditions the fracture surface was not smooth and has more secondary cracks as compared to static loading. 相似文献
70.
Xiaowu Hu Hua Yang Tiantong Guo Dehua Shu Wenfei Shan Guizhi Li Dongcai Guo 《Ceramics International》2018,44(7):7535-7544
The long afterglow nanomaterials of strontium aluminate co-doped by Eu and Dy have been synthesized by co-precipitation combined hydrothermal method. The effects of hydrothermal time, calcination time, pH value, the amount of aluminum nitrate, activator, co-activator and flux H3BO3 on the fluorescence properties of the product were investigated by means of single factor optimization experiment. Then the orthogonal experiment was employed to obtain the optimal synthesis conditions that are as follows: nDy/nEu = 2.5, tc = 2.5?h, nEu/nSr = 0.02, th = 8?h. Subsequently, the optimal synthesis conditions were verified by three repeated experiments, and the obtained products were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and fluorescence spectrometer. The results showed that the synthesized target products all were the mixed crystal phase of SrAl2O4 and Sr4All4O25. The particles presented regular spherical-like with size ~ 100?nm. The dopants Eu and Dy were confirmed existed in the SrAl2O4 powders. The fluorescence and afterglow data of the target products were better than that in the orthogonal experiment scheme. The primary emission spectra band was in the range of 400–600?nm with characteristic peak located at ~ 460?nm corresponding to the transitions of Eu2+ ions from 4f65d→4f7, and the blue light can be observed by naked eyes. The similar fast-decaying and slow-decaying processes were displayed in all the afterglow curves, and the initial afterglow brightness of the target product is apparently higher than that of products synthesized by the orthogonal experiment. The synthesized target products, which show excellent long afterglow performance, present a great application prospects in the aspects of ceramics, plastics, arts and crafts, ink and coating. 相似文献