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871.
Guoxi Xie Songlin Feng Xiangqian Feng Jihao Zhu Yongqiang Li 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,264(1):103-108
Imitated GE ware was one of the most famous products of Jingdezhen porcelain field in Ming dynasty (AD 1368-1644). The exterior features of its body and glaze are very marvelous. Black foot, purple mouth and crazing glaze are the main features of imitated GE ware. Until now, the key conditions of resulting these features are not clearly identified. In order to find the critical elements for firing these features, instrumental neutron activation analysis (INAA) and wavelength-dispersive X-ray fluorescence (WDXRF) were used to determine the element abundance patterns of imitated GE ware body and glaze. The experimental data was compared with that of imitated Longquan celadon and of Longquan celadon. The analytical results indicated that Fe, Ti and Na were the critical elements. The body of imitated GE ware which contains high Fe and Ti are the basic conditions of firing its black body, black foot and purple mouth. The glaze of imitated GE ware which contains high Na is the main condition of producing its crazing glaze. Na is the critical element which enlarges the difference in expansion coefficients between the glaze and body of imitated GE ware. Furthermore, Zijin soil was added into kaolin to make the body rich in Fe and Ti. And something which was rich in Na was used to produce crazing glaze in the manufacturing process of imitated GE ware. 相似文献
872.
简述了18—8不锈钢的凝固特点以及影响连铸坯振痕深度的因素。通过优化连铸振动工艺,提高拉速与振频,选择适宜的保护渣等,有效地降低了18—8型不锈钢连铸坯振痕到0.33μm以下,达到了铸坯无修磨轧制要求。 相似文献
873.
介绍了宝鸡民营钛工业在新材料、新技术、新设备、新应用方面的进展,提供了市场需求与发展前景方面的相关信息,并对中小型钛加工企业的发展提出建议。 相似文献
874.
Xiaodan Zhang Wei Liu Dale Sun Youguo Li 《Metallurgical and Materials Transactions A》2007,38(3):499-505
The transformation of carbides with austenization time of a high speed steel (HSS) roll material, manufactured by a centrifugal
casting method, has been studied. The correlation between wear resistance and the type, morphology, volume fraction, and distribution
of the carbides has also been investigated. Microstructural observations, X-ray diffraction (XRD) analysis, hardness measurements,
and energy dispersive spectroscopy (EDS) have been used to characterize the carbides. The type and volume fraction of carbides
were found to change with austenizing time. During austenization, the transformation of the M3C carbides can be postulated as M3C + γ-Fe → M2C, with much finer nodular and rodlike MC carbides also forming through a solid-state transformation. The M2C carbide decomposes as M2C + γ-Fe → MC + M7C3 + M6C. The decomposed carbide substantially maintains a platelike shape until the end of decomposition. The most important finding
of this study is that austenization results in changes in the type, morphology, volume fraction, and distribution of carbides
and that it can be controlled to produced a homogeneous distribution of hard carbides, resulting in an improvement in the
wear resistance of HSS rolls. This finding may be of great use for the industrial production of HSS rolls. 相似文献
875.
Real-time homogenous translucent material editing 总被引:4,自引:0,他引:4
This paper presents a novel method for real-time homogenous translucent material editing under fixed illumination. We consider the complete analytic BSSRDF model proposed by Jensen et al. [ [JMLH01] ], including both multiple scattering and single scattering. Our method allows the user to adjust the analytic parameters of BSSRDF and provides high-quality, real-time rendering feedback. Inspired by recently developed Precomputed Radiance Transfer (PRT) techniques, we approximate both the multiple scattering diffuse reflectance function and the single scattering exponential attenuation function in the analytic model using basis functions, so that re-computing the outgoing radiance at each vertex as parameters change reduces to simple dot products. In addition, using a non-uniform piecewise polynomial basis, we are able to achieve smaller approximation error than using bases adopted in previous PRT-based works, such as spherical harmonics and wavelets. Using hardware acceleration, we demonstrate that our system generates images comparable to [ [JMLH01] ]at real-time frame-rates. 相似文献
876.
877.
Jianying Li Shengtao Li Fuyi Liu M. A. Alim 《Journal of Materials Science: Materials in Electronics》2006,17(3):211-217
The post-sintering heat treatment on the current-voltage behavior of the ZnO-Bi2O3 based varistors is reported. It is suggested that only phase transition of the Bi2O3 is not alone responsible for the resulting electrical performance by these devices. The ambient condition influences the
performance parameters. Thus, incorporating the role of oxygen and zinc interstitial in the total device during the post-sintering
heat-treatment is accounted as responsible parameters for the ultimate performance. Two recipes are used in demonstrating
the effect of heat-treatment on the functional behavior of the devices. 相似文献
878.
公共娱乐场所消防安全现状及对策 总被引:1,自引:0,他引:1
卿婉丽 《消防技术与产品信息》2005,(5):22-23
从消防安全管理的角度,论述了公共娱乐场所消防安全存在的主要问题和如何进一步加强公共娱乐场所的消防安全工作 相似文献
879.
880.
锝化学研究 Ⅸ.脑显像剂Tc~(Ⅴ)ON_2S_2类配合物结构稳定性和价态的研究 总被引:1,自引:0,他引:1
采用改进的CNDO/2法模拟了BAT类脑显像剂Tc(Ⅴ)O配合物价态的转换过程,发现N2S2类配体与Tc(Ⅴ)O核配位时,可能存在配位平衡离子X。在溶液中由于X离子的优先解络,瞬间存在+1价对称性99Tcm配合物,并且,它又自动向相对稳定的0价不对称性99Tcm配合物转换,在动态转换过程中,将导致仅有一个配位N原子保留一个质子,这与实验结果一致。采用键级削弱百分数概念,表征配位过程的二个配位N原子上保留程度,解释了Tc(Ⅴ)O核、Tc(Ⅴ)≡N核N2S2类配合物两个N-H键上质子保留程度不同的原因,为今后设计不同价态锝配合物结构提供理论依据。 相似文献