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71.
72.
对皖南地区的早期矿冶遗址进行综合考察研究,发现存在着配制锡青铜、砷青铜、锑青铜的3种合金技术。青铜冶炼流程为两步法,所用铜料、砷料、锑料应来自当地,锡料推测来自长江中游的赣北且主要以锡砂形式添加。研究还发现,以皖南为代表的长江下游是中国早期又一处重要的砷青铜冶金区,其生产流行的资源背景应与该地区缺乏锡矿有关。研究进一步预示长江流域存在着相当规模且独具特色的早期青铜冶金业,而与黄河流域的中原地区有明显区别。 相似文献
73.
In float glass manufacturing, the glass is often stained with tin, which will result in deficient quality. The amount of stained tin is related to five factors: temperature, oxygen content in tin liqnid, bath pressure, total amount of protecting gas, and the thickness of the glass. On the basis of the experimental data, and through system reconstruction analysis, each factor's value range where there is not any tin stain on the float glass is found. 相似文献
74.
每次更换罐道木之前都会提前对罐道木进行加工,但是井筒罐道木的加工制作非常困难,不仅劳动强度大,而且效率低。为此,研制了以台式刨床刨头为主刀具,锥形伞齿轮传动为主传动系统,配有木料长形底托架、尺寸精度调节装置、线缆拖动装置的加工罐道木的简易龙门刨床,应用实践效果很好。 相似文献
75.
SnO2 intermediate layers were coated on the titanium (Ti) substrate by thermal decomposition. Scanning electron microscope (SEM) and X-ray diffraction (XRD) results show that uniform SnO2 intermediate layers with rutile crystal structure were successfully achieved. According to the results of linear sweep voltammetry (LSV), oxygen evolution potential (OEP) of the Ti/SnO2/MnO2 electrodes decreases with increasing SnO2 content, indicating that the electro-catalytic oxidation activity of the electrode increases. Accelerated service life tests results demonstrate that SnO2 intermediate layer can improve the service life of the Ti/SnO2/MnO2 electrode. As the content of SnO2 intermediate layer increases, the cell voltage and the energy consumption decrease apparently. 相似文献
76.
77.
Tommy Lorenz Igor A. Baburin Jan-Ole Joswig Gotthard Seifert 《Israel journal of chemistry》2017,57(6):553-559
The present paper compares and discusses two selected misfit (layer) compounds exemplarily, namely SnS-SnS2 and LaS-TaS2. We have employed a density-functional theory-based approach to calculate structural, energetic, and electronic properties of these structures. We have put emphasis on the difference between single layers, combined double-layer systems and periodically stacked bulk structures. Especially the varying magnitudes of charge transfer between the sublayers were studied. We demonstrate how the chemical constitution of the sublayers affects the interlayer interactions: these may be a weak non-bonding van-der-Waals dominated interlayer interaction as in SnS-SnS2 and many other layered structures or a strong interaction related to a remarkable charge transfer between the layers as in LaS-TaS2. 相似文献
78.
This paper reports the synthesis of Co2SnO4@C core-shell nanostructures through a simple glucose hydrothermal and subsequent carbonization approach. The as-synthesized Co2SnO4@C core-shell nanostructures have been applied as anode materials for lithium-ion batteries, which exhibit improved cyclic performance compared to pure Co2SnO4 nanocrystals. The carbon matrix has good volume buffering effect and high electronic conductivity, which may be responsible for the improved cyclic performance. 相似文献
79.
80.
An effective boron removal method was developed through a process of combining Si–Sn alloy with slag treatment. Boron content in refined silicon and boron removal fraction by slag containing 5 wt% CaO, 25 wt% SiO2 and 70 wt% Na2SiO3 and was investigated under varied Si–Sn alloy composition, slag/Si–Sn alloy mass ratio and refining time. Boron was effectively removed by adding tin to metallurgical grade silicon. In particular, the boron content in metallurgical grade silicon decreased from 12.92 ppmw to 0.79 ppmw by adding 50 at% tin under a mass ratio of 2:1 (slag:alloy) at 1723 K. The amount of boron removed increased with increasing amount of tin added, mass ratio and refining time. 相似文献