The ceramic industry widely uses synthetic black pigments as coloring agents for glazes and ceramic bodies. Almost 25 wt% of these pigments are black. They come from two main crystalline structures: hematite and spinel.1 The formulations that simultaneously form the correct spinel structure and yield high-intensity black pigments belong to the complex system CoO–NiO–MnO–CuO– FeO–Fe2O3–Cr2O3–Mn2O3–V2O3–Al2O3. Other oxides also might be present, although not exceeding ~3%. Commercial black pigments normally are based on the spinel structure because of its higher stability. They are derived from iron cobalt chromite, (Fe,Co)(Fe,Cr)2O4 (DCMA 13-40-9) or chrome iron nickel, (Ni,Fe)(Fe,Cr)2O4 (DCMA 13-50-9) compounds.1–3 Some of the metallic constituents are scarce and expensive. Therefore, there is great interest in developing high-stability pigments from alternative and less-expensive raw materials that show intense tonalities and comply with technological and environmental demands. We and others have investigated selected industrial wastes for this purpose. In particular, properly homogenized metal-rich sludges show promise. Less-pure raw materials prove superior for producing a given pigment. This might be the case with black spinel pigments because of the relatively wide capacity of this structure to accommodate distinct transition-metal ions, in either tetrahedral or octahedral forms with sizes of 0.06 nm < rt < 0.1 nm and 0.055 nm <ro <0.1 nm, respectively. This diversity also might accentuate the obtained black hue and generally help to decrease the sintering temperature because some elements act as mineralizers. We detail in this article the compositional refinement of a black spinel pigment obtained by combining two sludges: chromium–nickel-rich sludge generated from a chromium–nickel plating process and iron-rich galvanizing sludge generated in a steel wiredraw process. We derived this work from one reported earlier.
我们已经评估的过渡金属氧化物中的功率因数在使用Heikes式及约费 - 葱电导率高的温度。所评估的功率因子被发现是近独立载流子浓度在很宽的范围内掺杂，并解释了实验数据为钴氧化物良好。这表明，在相同的功率因数可以与热电比2kB的/ e值越大而获得，并且也表明性能指数ZT的无量纲的一个相当高的值。我们通过使用具有热电比300 MUV / K较大的材料提出了氧化物热电发电机
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