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1.
春秋战国时期既是中国传统文化的大变革时期,又是工艺美术发展的创新时期,传统的模式不断被超越,新的风格相继被确立。春秋战国时期青铜器凤鸟纹饰在不断突破商周时期传统样式过程中,呈现出崭新的审美情趣与独特的装饰意匠。  相似文献   
2.
通过固相反应法合成了Sr0.6Ba0.4Nb2O6陶瓷,并对其进行了结构、介电性能的表征。结果表明Sr0.6Ba0.4Nb2O6陶瓷为四方钨青铜结构单相,其在60℃附近存在一个明显的弥散介电峰,峰值温度随频率向高温偏移,为典型的弛豫铁电相变。室温时,10kHz频率下,其介电常数约为1404,介电损耗为0.03。  相似文献   
3.
The electrochemical behavior of the bronze (Cu-8Sn in wt%) was investigated in 3% NaCl aqueous solution, in presence and in absence of a corrosion inhibitor, the 3-phenyl-1,2,4-triazole-5-thione (PTS). The inhibiting effect of the PTS was evidenced for concentrations higher than 1 mM for the cathodic process whereas its effect was clearly seen with a concentration as low as 0.1 mM for the anodic process. A significant positive shift of the corrosion potential was also observed, and its inhibiting effect increased with both its concentration and the immersion time of the sample. From voltammetry and electrochemical impedance spectroscopy experiments, the inhibiting efficiency of the PTS was found to be in the 94-99% range for 1 mM concentration. Scanning electron microscopy and X-ray energy dispersion analysis of the specimen surface show the presence of sulphur on the surface. Raman micro-spectrometry study confirms the protective effect of the PTS in aqueous solution through three types of interactions with the electrode, namely the adsorption of the inhibitor in a flat configuration, the formation of copper-thiol molecules, and when copper is released, the formation of a polymeric complex.  相似文献   
4.
研究了锑、锌、锰等合金元素对锑青铜的组织和性能的影响,经过大量试验,研制出具有良好综合性能的新型锑青铜材料,是目前替代锡青铜材料的理想材料。  相似文献   
5.
ABSTRACT

The gold work from the Western European Middle and Late Bronze Age (about 1500–700 BC) is characterized by solid ornaments and vessels. This article deals with manufacturing techniques of heavy gold jewelry by presenting a gold hoard found at Guînes, Pas-de-Calais, in Northern France, as a case study. In particular, three ornament types will be taken into consideration: (1) solid penannular neck and arm-rings, plain or with linear or geometric decoration; (2) flange-twisted ornaments that appear in different dimensions, as small as ear rings, as neck rings, up to the large size of a belt; (3) complex, composite ornaments. The technological aspects dealt with in this precious metal working context are manifold, including ingot and lost wax casting, hammering and bending of solid rods, the production of flange-twisted rods, chasing as decoration method, and finally joining techniques such as soldering, riveting and folding, and creasing.  相似文献   
6.
KxWO3+x2 (x = 0.3) thin films have been prepared by the thermal vacuum evaporation technique. Depending on the substrate temperature during deposition, either amorphous or crystalline films could be obtained. X-ray diffraction patterns and pole-figure information revealed that fresh crystalline films deposited on a hot (about 400°C) substrate of indium-tin oxide on glass microscope slides had a preferred orientation, with the c-axis perpendicular to the surface of the film. SIMS depth profiles and RBS experiments were used to confirm the stoichiometry and uniformity of the chemical components in the thermally deposited films.  相似文献   
7.
Castings made of copper–nickel–aluminium bronze (CuAl10Fe5Ni5) alloys regularly show defects in the thick, slowly solidifying parts of the castings, which give rise to rejections. Metallographic examination has been made on material of scrap castings showing porosity accompanied with film-like inclusions located beside the iron rich κII phases. Investigations of large failed cast structures of copper–nickel–aluminium bronze show the same characteristic defects on which fatigue cracks initiate and grow. Investigation has been made to the nature and the cause of appearance of the film-like inclusions. Microanalysis indicates a high intensity of carbon at the place of the film-like inclusions. Hereafter, an investigation has been made into the solubility of carbon in liquid copper–nickel–aluminium bronze, and it is found that besides hydrogen, also carbon is soluble in copper–nickel–aluminium bronze alloys. The appearance of the carbon as flakes in the fracture surface of materials with defects does suspect there is a nucleating effect on the formation of microporosity causing the defects. To prevent the formation of the casting defects by the interaction between solved hydrogen and carbon, it is necessary to remove the carbon as far as possible by treatment of the melt.  相似文献   
8.
结合高34m观音铜像实例,就如何进行铜像壁板的分块设计,对分块的切分线、分块面积的大小、壁板的厚度及其他有关进行了论述。还 就实际选定的壁板厚度,在设计风速下,对它的强度及所产生的位移进行了核算。  相似文献   
9.
溶液pH值与氯离子对青铜腐蚀的影响   总被引:6,自引:0,他引:6  
青铜文物在大气中的腐蚀实质上是金属表面在水膜下的电化学过程,故可以用电化学方法进行研究。青铜的阳极极化曲线表明青铜是一种弱纯化金属,在含氯离子和含氧气的溶液中容易发生点蚀。  相似文献   
10.
金正耀 《质谱学报》2005,26(Z1):73-74
A data base of lead isotope ratio of ancient Chinese bronzes is set up. There are 2 888 members, including bronze objects, casting remains, and related ores, etc. in the file. The file contents of data base are made from analysis work on Chinese bronze previously carried out in several laboratories in China, Japan and USA. The main body of the file contents is formed from records, analysis data, reference documents, and images. The data base is designed for sharing information in provenance study on raw metal material for bronze production in China Bronze Age.  相似文献   
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