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1.
Qianying Hoo Xiaohu Wang Feng Yuan Xuewei Cao Tiewa Cao Maolin Zhang 《Journal of the European Ceramic Society》2021,41(6):3816-3822
Jingdezhen is famous for its bluish white (Qingbai) porcelains of the Song Dynasty, and those decorated with iron spots are distinctive among them. Herein, iron spots on a bluish white porcelain were investigated using a series of microscopic and spectroscopic characterizations. We found the decreasing iron content from more than 8 wt% to about 2 wt% during the glaze color transition from rusty to brown and finally into green, which built a connection on the coloring mechanism of iron-rich crystallized glaze and celadon glaze. We identified the rare ε-Fe2O3, a promising magnetic material, in both the dark brown crystals and the triangular crystals in the rusty area, which is its first discovery among bluish white porcelains. Based on these findings, we discussed the coloring mechanism of iron-spot decoration along with the physical form of the iron oxide crystals, indicating the partially reducing atmosphere during firing process. 相似文献
2.
熔融制样-X射线荧光光谱法(XRF)测定硅铁合金样品,需重点解决样品前处理中合金样品侵蚀铂-黄坩埚的难题。硅铁样品以四硼酸锂-碳酸锂预氧化剂在石墨垫底瓷坩埚中高温预氧化熔融后,再将熔融物转移至铂-黄坩埚中,用四硼酸锂熔融制成玻璃熔片,实现了熔融制样-X射线荧光光谱法对硅铁合金中硅、磷、锰、铝、钙、铬的测定。实验讨论了预氧化熔融的熔剂体系及氧化方法、试样与熔剂的稀释比,结果表明,试样与熔剂以1∶35的稀释比,以10滴300g/L碘化钾溶液为脱模剂,在1100℃熔融30min,熔融制得的玻璃片均匀、透明、无气泡,符合测定要求。用具有浓度梯度的系列硅铁有证标准样品制作校准曲线,各待测元素校准曲线的线性相关系数均大于0.9995。方法应用于硅铁合金实际样品中硅、磷、锰、铝、钙、铬的测定, 结果的相对标准偏差(RSD,n=11)在0.1%~5.8%之间;正确度试验表明,硅铁标准样品的测定结果与认定值相符,硅铁实际样品的测定结果与国家标准方法测定值一致,能满足常规分析要求。 相似文献
3.
牡丹纹作为为元明清青花瓷中重要的装饰之一最晚出现瓷器不过宋代,布局和绘画方式变化多样。主要特点为枝叶舒展或是多枝相交,花朵怒放被枝头环抱。明朝时期也是青花瓷发展的一个重要阶段,本文通过对现存明朝时期的青花牡丹纹饰例,分别分析不同风格和技法的青花牡丹纹饰,从而论证其艺术特色,以及对后期造成的影响。 相似文献
4.
《Ceramics International》2015,41(8):9878-9884
The provenance of cobalt mineral of the blue decoration in Yuan Qinghua porcelain would reveal the technological and cultural interaction between ancient China and the Islamic world. However, the limitation of conventional methods in the determining trace elements of the blue decoration hampered the deep research on provenance of the cobalt mineral. In the paper, we employed the good advantage of Laser-ablation-inductively-coupled-plasma-mass-spectroscopy (LA-ICP-MS) to determine the major element and trace elements of blue decoration of the different type of Qinghua successfully. The blue decoration of all different types of samples shared the same characteristics of higher FeO and lower Mn, which suggested the potter adopted the non-native cobalt material of China to paint the Yuan Qinghua in Jingdezheng, and the difference on the outside appearance of blue decoration of different samples were supposed to be related to the tenor of ore, the different treatment process of cobalt material and the firing process in the kiln. In addition, the significant differences on the element concentrations of Cu, Ni, Pb, Zr and Sb in the blue decoration between Yuan Qinghua and the Islamic blue and white wares of 13–14th century provided a new evidence to discuss the provenance of the cobalt of Yuan Qinghua porcelain. 相似文献
5.
《Ceramics International》2020,46(9):13474-13481
Witte Leeuw was a cargo ship owned and operated by the Dutch East Indian Company. The wreck of this vessel is known for yielding a comprehensive range of Jingdezhen manufactured, blue-and-white export porcelains, particularly kraak wares; together with Fujian blue-and-white export porcelains, known as Swatow wares. A large number of ceramic fragments have been recovered from this wreck and currently reside in collections at the Rijksmuseum. For this study nine ceramic specimens were selected for further investigation, with the aim of determining the structure, composition and manufacturing process of the double-layer glazes. Both digital optical microscopy and scanning electron microscopy were used to examine the glaze morphology and microstructure; whilst energy dispersive x-ray spectroscopy was utilised to measure the spatial distribution of chemical elements and to determine bulk elemental compositions. Raman spectroscopy was also trialled, with the technique being applied to the measurement of molecular vibrations within the silicon-oxygen network and associated alkali metal oxides, with the aim of identifying potential differences in the glaze layers. Examining the ceramic specimens, the blue decorations were applied between two layers of glaze, and the majority of the blue colour extends into the outermost layer, often exhibiting dissolution in the outer layer glaze. The two layers of the glaze appear to be formulated from different compositional recipes. Some export Swatow blue-and-white wares made in the Wanli Period (1573–1620) were glazed twice and fired twice. 相似文献
6.
7.
简要介绍了唐山市高压电瓷有限公司修坯现状,重点从电气、机械及工艺等方面分析了采用数控电瓷修坯机加工坯件导致尺寸不稳定的原因。采取降低泥料与修坯机之间磨损、将修坯用泥段水分控制在15%~20%等措施后,可提高产品的合格率。 相似文献
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9.
采用煤渣、废瓷粒等工业废渣为骨料,以石灰石、白云石、长石、高岭土、石英和瓷石粉的混合料为高温粘结剂制备陶瓷透水砖,研究工艺参数对透水砖性能的影响。结果表明,随着煤渣用量的增加或成型压力的降低,透水砖的透水性能提高而机械强度降低。通过DTA-TG分析确定了在800℃保温4 h的优化烧成制度,有效避免了黑心和变形缺陷的产生。FE-SEM显微照片表明,合理的煤渣颗粒级配能使煤渣粗颗粒间形成孔径为0.5~1.5 mm的大气孔,而煤渣颗粒本身由于其中可燃物燃烧形成了孔径为数十个微米的微孔,这种特殊的结构赋予透水砖强度高、透水好的性能。 相似文献
10.