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During thermochemical conversion of biological material in a fluidized bed reactor the nutrients are remaining as dust in the product gas. Hot gas filtration represents a possibility to recover these minerals. The characteristics of this gas add up new technical tasks. The following article gives an account of long lasting experience of operation and optimization in a pilot plant. 相似文献
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以Mg(NOa)2·6H20为镁源,以Al(N03)3·9H20为铝源,采用共沉淀法制备了阴离子型层状材料Mg-A1-COjLDHs,并用X射线衍射(XRD)、傅里叶变换红外光谱(Fr—IR)、扫描电镜(SEM)和透射电镜(TEM)对产物进行了表征。探讨了加料方式、插层阴离子的用量以及沉淀反应温度对所形成产物物相等的影响。XRD分析结果显示不同加料方式所制备的产物均具有典型的层状结构特征,其中pH恒定法所合成的产物结晶度更高;红外光谱显示产物中存在插层阴离子C023-;EDX元素分析结果表明产物组成中含有Mg和Al,且n(镁):”(铝)=2.6。上述表征结果说明:加料方式、插层阴离子的用量以及沉淀反应温度对产物的物相没有影响,但对产物的结晶度有一定的影响。当初始原料的配比为n(Mg):n(A1):n(OH):n(C()23-)-6:2:20:2时,在45℃下完成沉淀反应,再将沉淀于65℃下晶化18h可以得到具有典型层状结构的Mg-A1一C0;一LDHs。 相似文献
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《Journal of the European Ceramic Society》2020,40(5):1801-1810
The residual carbon content of ultra-fine hafnium carbide (HfC) powder was controlled by the optimization of the synthesis process, and the effect of residual carbon on the densification of HfC powder was analyzed. The amount of residual carbon in the HfC powder could be reduced by the de-agglomeration of HfO2 powder before the carbo-thermal reduction (CTR) process. The average particle size of HfO2 powder decreased from 230 to 130 nm after the de-agglomeration treatment. Ultra-fine (d50: 110 nm) and highly pure (metal basis purity: >99.9 % except for Zr) HfC powder was obtained after the CTR at 1600 °C for 1 h using the C/Hf mixing ratio of 3.3. In contrast, the C/Hf ratio increased to 3.6 without the de-agglomeration treatment, indicating that a large amount of excess carbon was required for the complete reduction of the agglomerated HfO2 particles. HfC ceramics with high relative density (>98 %) were obtained after spark plasma sintering at 2000 °C under 80 MPa pressure when using the HfC powder with low excess carbon content. In contrast, the densification did not complete at a higher temperature (2300 °C) and pressure (100 MPa) when the HfC powder contained a large amount of residual carbon. The results clearly indicated that residual carbon suppressed the densification of HfC powder in case the carbide powder had low oxygen content, and the residual carbon content could be controlled by the optimization of the synthesis process. The average grain size and Vickers hardness of the sintered specimen were 6.7(±0.7) μm and 19.6 GPa, respectively. 相似文献
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阐述了C5石油树脂的结构、性能及聚合机理;综述了氯铝酸离子溶液等新型催化剂、合成技术、加氢改性工艺和新型精制催化剂的研究进展,以及C5石油树脂用作柴油降凝剂和路标漆的最新应用研究。指出了加氢精制技术生产高软化点、无色的石油树脂是今后C5石油树脂的发展方向。 相似文献
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Christopher D. GabbuttLucy V. Gibbons B. Mark Heron Suresh B. Kolla 《Dyes and Pigments》2012,92(3):995-1004
A series of 2H-naphtho[1,2-b]pyrans bearing a diarylmethanol unit at C-5 have been synthesised by the addition of an excess of an aryllithium reagent to alkyl 2H-naphtho[1,2-b]pyran-5-carboxylate precursors. These naphthopyrans show photochromism when exposed to ultraviolet irradiation and also generate intense colours at low pH through triarylmethine cation generation. However, photochromism of the triarylmethine cation derived from the naphthopyran unit could not be detected. An irreversible cascade process initiated by the thermally-induced ring-opening of the diarylmethanol substituted 2H-naphtho[1,2-b]pyrans in the presence of an acid catalyst afforded novel benzopentalenonaphthalenone dyes. 相似文献
100.
Liang HuJie Qin Nan ZhouYi-Fei Meng Yan XuJing-Lin Zuo Xiao-Zeng You 《Dyes and Pigments》2012,92(3):1223-1230
Metal complexes containing a new multi-sulfur atom containing 1,2-dithiolene ligand, [4′,5′:5,6] [1,4] dithiino[2,3-b] quinoxaline-1′,3′-dithiolate, have been synthesized and characterized by electrochemical measurements, IR, UV-NIR and ESR spectroscopies. X-ray structure analysis reveals that the anions of the Ni-complex derived from the new ligand form a zig-zag chain along the b axis, and the anions of Au complex of the ligand stack along the a axis while the cations occupy the holes. The Ni-complex exhibits remarkable absorption at 1082 nm (? = 15?000 dm3 mol−1 cm−1) and good solubility that render this complex as a promising near-IR dye for Q-switching neodymium lasers. The third-order non-linear optical properties of the complexes are measured by the Z-scan technique with a 6.5 ns pulsed laser at 532 nm. The Au complexes exhibit non-linear optical absorptive abilities, while the non-linear absorption of the nickel complex is negligible. All of the complexes show effective self-defocusing performance. The third-order non-linear optical susceptibilities for the Au complexes have been determined to be of the order of 10−13 esu. 相似文献