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921.
Hairus Abdullah Chi-Ning Hsu Hardy Shuwanto Noto Susanto Gultom Worku Lakew Kebede Chang-Mou Wu Chiu-Chun Lai Ri-Ichi Murakami Masayuki Hirota Antonio Norio Nakagaito Dong-Hau Kuo 《自然科学进展(英文版)》2021,31(3):404-413
Relatively small amounts of In-doped Mo(O,S)2 (IMS) catalysts (10%, 20%, and 30%) were deposited on cellulose nanofiber (CNF) by cross-linking them with functional groups of siloxane and epoxy to form CNF-IMS hybrid composites. The as-prepared hybrid composites were characterized and tested their performances toward the photo degradations of cationic (MB and RhB) and anionic (MO) dyes. As indium was doped into Mo(O,S)2 lattice to form solid-solution, the charge transfer and photocarrier separation during the catalytic reaction were simultaneously enhanced as probed with electrochemical impedance spectroscopy and photoluminescence measurements, respectively. To ensure the catalyst on CNF was well deposited and recyclable, the hybrid composite was evaluated with a reusability experiment to show the stability performance in degrading organic dyes. It was found the environmentally friendly CNF-IMS hybrid composite was relatively stable during the reusability experiment, indicating no catalyst powder was leached out during the photocatalytic reaction. The photoreaction mechanism was convinced by radical-scavenging experiments to show that hydroxyl and superoxide played essential roles for the organic dye degradations in visible-light illuminated conditions. The cross-linked organic/inorganic hybrid catalyst showed a prospective visible light active material not only to solve the environmental issue due to the leaching of nanoparticles but also to lower the post-treatment/recycling cost of photocatalyst in industrial application. 相似文献
922.
923.
In this study, we explore the effect of cojumps within the agricultural futures market, and cojumps between the agricultural futures market and the stock market, on stock volatility forecasting. Also, we take into account large and small components of cojumps. We have several noteworthy findings. First, large jumps may lead to more substantial fluctuations and are more powerful than small jumps. The effect of cojumps and their decompositions on future volatility are mixed. Second, a model including large and small cojumps between the agricultural futures market and the stock market can achieve a higher forecasting accuracy, implying that large and small cojumps contain more useful predictive information than cojumps themselves. Third, our conclusions are robust based on various robustness tests such as the realized kernel, expanding forecasts, different forecasting windows, different jump tests, and different threshold values. 相似文献
924.
925.
This paper combines the theory of teams and data envelopment analysis (DEA) to design a mechanism to optimally allocate resources in public healthcare. A statutory authority and the public hospitals under its governance are interpreted as a team, the members of which seek to operate efficiently under the shared institutional constraint that public healthcare is a public good. The individual public hospital exploits DEA to maximize own-payoff, subject to the team-condition that the payoff of each other public hospital does not fall and thereby subtract from the external effects created by the public supply of healthcare. The resulting team-DEA solution, which is shown to be both an individually-efficient and team-satisficing equilibrium and to be computable in terms of a convergent algorithm, can then be applied by the authority to determine the optimal allocation of resources in public healthcare. A case based on Chinese data is presented to illustrate the team-DEA model’s ready operationalization and computation. 相似文献
926.
The present work employed the X-ray diffraction, scanning electron microscopy, electron backscattered diffraction, and electron probe microanalysis techniques to identify the microstructural evolution and mechanical and abrasive behavior of high carbon steel during quenching-partitioning treatment with an aim to enhance the toughness and wear resistance of high carbon steel. Results showed that, with the increase in partitioning temperature from 250 to 400°C, the amount of retained austenite (RA) decreased resulting from the carbide precipitation effect after longer partitioning times. Moreover, the stability of RA generally increased because of the enhanced degree of carbon enrichment in RA. Given the factors affecting the toughness of high carbon steel, the stability of RA associated with size, carbon content, and morphology plays a significant role in determining the toughness of high carbon steel. The analysis of the wear resistance of samples with different mechanical properties shows that hardness is the primary factor affecting the wear resistance of high carbon steel, and the toughness is the secondary one. 相似文献
927.
本文采用测定水化过程结合水量、XRD和 SEM等技术研究了纯高钙粉煤灰的水化及S—激发剂对高钙粉煤灰的激发作用。结果表明 ,高钙粉煤灰由于含有较多的 f Ca O,水化时产生较大的膨胀而使试样粉化、无一点强度 ,掺入 S—激发剂可较好地激发高钙粉煤灰的潜在水硬性 ,增加水化过程结合水量 ,从而使掺有 S—激发剂的高钙粉煤灰试样水化不同龄期后均有一定的强度 相似文献
928.
低碱度钢渣基油井及地热井胶凝材料的研究——Ⅰ低碱度钢渣的化学成分、矿物组成和矿相特征 总被引:1,自引:1,他引:0
通过化学分析、XRD、OM研究了低碱度钢渣的化学成分、矿物组成和矿相特征及其内在联系 ,建立了低碱度钢渣的分类概念。低碱度钢渣是指碱度小于 2 .4,以橄榄石、镁蔷薇辉石、RO相、硅酸二钙为主要矿物的钢渣 相似文献
929.
本文研究了 Ca O—Mg O—Si O2 — H2 O体系的水热反应特性。结果表明 :在 Ca O— Mg O—Si O2 一 H2 O系统中 ,Ca O优先与 Si O2 反应生成水化硅酸钙 ,Mg O部分固溶于水化硅酸钙中 ,部分生成 Mg( OH) 2 ,部分与剩余的 Si O2 反应生成水化硅酸镁 ;Mg O固溶时 ,可促进托勃莫来石向硬硅钙石转化 ,不固溶 ,则其转化温度提高 相似文献
930.
杨来侠 《西安科技大学学报》2000,(Z1)
科技发展相对滞后和人力资源匮乏是制约西部地区经济发展的主要因素。在西部大开发中高等院校应充分发挥自身的技术和人力资源集中的优势 ,通过科技创新、加快与西部大开发相关的学科体系建设、产学研相结合等途径 ,为西部大开发提供科学技术和人力资源支持。为当地经济建设服务的同时 ,使自身得到发展的壮大 相似文献