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71.
72.
The reduction of chromium-bearing vanadium–titanium magnetite sinter (CVTMS) by CO was investigated at 1123–1223?K. The reduction degree increased with increasing temperature. The isothermal reduction kinetics of CVTMS was analysed, according to Sharp analysis and ln–ln analysis, the kinetic mechanism of reduction process for all samples in different basicity can be represented as f(α)?=?1.61(1?α)[?ln(1?α)]1–1/1.61. The reaction activation energy of all samples (R?=?1.9, 2.1, 2.3, obtained according to the components of the materials burdening used in sintering process) at different reaction degrees were calculated by the model-free method. And the pre-exponential factors of reaction also were calculated by the mathematical method. The rate controlling step for the reduction process under the present reduction condition was chemical reaction. 相似文献
73.
Pan Zhibin Gao Erdun Zhu Ruoxin Wang Lingfei 《Multimedia Tools and Applications》2019,78(15):21223-21244
Multimedia Tools and Applications - Search order coding (SOC) benefits a lot from the correlation of neighboring blocks for vector quantization (VQ)-compressed images. SOC selects a number of... 相似文献
74.
Ting Hui Yuan Zhen Hua Zhang Jin Li Da Quan Zhang Li Xin Gao Wen Ge Li Zhi Feng Fan 《工业材料与腐蚀》2019,70(7):1298-1305
In the study, polyaniline/reduced‐graphene oxide (PANI‐RGO) composites, fabricated by loading 2, 5, and 8wt% graphene oxide, was prepared by in‐situ emulsion polymerization and reduction. They are characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, and scanning electron microscopy. Epoxy coatings adding PANI and PANI‐RGO composites were coated on the surface of AA5083 Al alloy. The anticorrosion performance of the coatings is measured by electrochemical impedance spectroscopy and potentiodynamic polarization curve in 3.5wt% NaCl solution. The results demonstrate that the epoxy/PANI‐RGO coating exhibits a better protection against AA5083 alloy corrosion compared with the epoxy/PANI coating. Enhancement of the passivation performance of PANI was obtained by the addition of RGO into epoxy/PANI coating system. 相似文献
75.
Research on sub-surface recrystallization of single crystal nickel-based superalloy in micro-milling
Journal of Mechanical Science and Technology - The micro-structure/parts of single crystal nickel-based superalloy materials are extensively used in high temperature environments. The... 相似文献
76.
Ryan S. Hippman Ivan Pavlinov Qiwen Gao Michelle K. Mavlyanova Erica M. Gerlach Prof. Leslie N. Aldrich 《Chembiochem : a European journal of chemical biology》2020,21(21):3137-3145
A systematic, diversity-oriented synthesis approach was employed to access a natural product-inspired flavonoid library with diverse chemical features, including chemical properties, scaffold, stereochemistry, and appendages. Using Cell Painting, the effects of these diversity elements were evaluated, and multiple chemical features that predict biological performance diversity were identified. Scaffold identity appears to be the dominant predictor of performance diversity, but stereochemistry and appendages also contribute to a lesser degree. In addition, the diversity of chemical properties contributed to performance diversity, and the driving chemical property was dependent on the scaffold. These results highlight the importance of key chemical features that may inform the creation of small-molecule, performance-diverse libraries to improve the efficiency and success of high-throughput screening campaigns. 相似文献
77.
78.
为制备大掺量磷石膏基复合胶凝材料,在确定主要水化产物类型的基础上,通过计算临界钙矾石膨胀破坏的边界条件,确定各组分最佳掺量范围,研究其对复合胶凝材料力学性能、干缩性能的影响,并通过X射线衍射(XRD)、扫描电镜(SEM)等测试方法研究水化产物的组成及发展规律。研究结果表明:通过理论配料计算,矿粉掺量为50%(质量分数)时,最大磷石膏掺量为26.3%(质量分数),最小熟料掺量为23.6%(质量分数)。最佳配比组28 d胶砂抗压强度为45.2 MPa,线膨胀率小于0.04%;对比组28 d抗压强度仅有36.4 MPa,线膨胀率远大于0.04%。XRD、SEM表征结果表明,磷石膏基复合胶凝材料的水化产物主要是钙矾石(AFt)和水化硅酸钙(C-S-H)凝胶,氢氧化钙几乎反应完全;对比组钙矾石生成量远大于最佳配料组,微观结构存在大量裂缝。这说明理论配料计算可以有效用于磷石膏基复合胶凝材料的配比优化。 相似文献
79.
80.
对生物质燃气中焦油的净化进行试验研究,通过在喷淋塔前设置空冷塔的焦油净化系统,并以稻秸秆为原料考察热解温度对生物质燃气中焦油在空冷塔和喷淋塔中的分配情况及化学组成的影响。结果表明,生物质燃气中80%的焦油可在空冷塔中富集,当热解温度由500℃升至750℃时,空冷塔中焦油的占比由84.26%降至80.55%,喷淋塔中焦油占比由15.74%升至19.45%;生物质焦油中超过99%、81%、84%和93%的酚类化合物、烷烯烃、含氮化合物和含氧化合物(除酚类化合物外)在空冷塔中富集,而超过76%的芳烃及其衍生物在喷淋塔中富集。 相似文献