Magnetically separable attapulgite−TiO2−FexOy composites with superior activity towards photodegradation of methyl orange under visible light radiation

Jiahui Zhang,Lili Zhang,Shouyong Zhou,Haiqun Chen,Hui Zhong,Yijiang Zhao,Xin Wang 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.5

A magnetically recoverable composite photocatalyst was obtained by introducing TiO2–FexOy hybrid oxide onto the surface of attapulgite via an in-situ deposit technique (marked as ATT–TiO2–FexOy-r, r represents molar ratio of r = nTi/(nTi + nFe)). The obtained composites were carefully characterized and results showed TiO2–FexOy particles with an average size of 10 nm were successfully loaded onto attapulgite fibers’ surface. The FexOy (mixture of Fe2O3 and Fe3O4) acted not only as magnetic source but also took part in the formation of TiO2–Fe2O3 heterojunction structure, which resulted in the obvious absorption in visible light region for the obtained ATT–TiO2–FexOy. The obtained ATT–TiO2–FexOy-r exhibited quite good catalytic activity towards photodegradation of methyl orange under visible light irradiation. The highest degradation ratio and COD removal of methyl orange reached to 94.13% and 90.91% for ATT–TiO2–FexOy-0.5. Moreover, ATT–TiO2–FexOy could be readily recovered and the degradation ratio maintains 83.89% after 5 cycles. Possible mechanism for this enhancement was proposed.

Construction of polysulfone anion exchange hybrid membranes by incorporating carbon quantum dots and facilitated transport mechanisms

Yuan Jin,Xiu Zhang,Tianci Feng,Mei-Sheng Li,Huifang Xiao,Shouyong Zhou,Yijiang Zhao,Jing Zhong,Dawei Yang 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.115 No.-

Low ion conductivity and poor alkali resistance are still the two major obstacles for the applications ofanion exchange membranes (AEMs). In this work, the combined strategies of Carbon quantum dots(CQDs) hybrid and cross-linking modification via side-chains designing were employed to prepareorganic–inorganic hybrid AEMs. Then, the cross-linked quaternized polysulfone (CQPSf-CQDs) hybridAEMs by incorporating carbon quantum dots were successfully fabricated. After hybrid and crosslinking,the mechanical properties of CQPSf-CQDs hybrid AEMs were higher than that of the pristineone, reaching 49.4 MPa for the best one. Meanwhile, the existence of CQDs can expand the hydrophilicarea in the membrane, which is beneficial to the transport of OH. The incorporated CQDs interact weaklywith cationic groups in the side chains through hydrogen bonds. The simulation results further demonstratedthat the introduction of CQDs was beneficial to the construction of hydrophilic and hydrophobicdomains, thereby increasing OH conductivity. In addition, the prepared hybrid membranes own excellentdimensional stabilities and ion transport performances. These preliminary results give us a lot ofhopes for further experiments and optimizations for the hybrid AEMs.

Selective transformation of biomass-derived 5-hydroxymethylfurfural into 2,5-dihydroxymethylfuran via catalytic transfer hydrogenation over magnetic zirconium hydroxides

Lei Hu,Mei Yang,Ning Xu,Jiaxing Xu,Shouyong Zhou,Xiao-Zhong Chu,Yijiang Zhao 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.1

An economical and effective approach for the selective transformation of biomass-derived 5-hydroxymethylfurfural (HMF) into 2,5-dihydroxymethylfuran (DHMF) was developed by catalytic transfer hydrogenation over various magnetic zirconium hydroxides (MZHs). As expected, MZH with a moderate Zr/Fe molar ratio of 2 displayed the highest catalytic activity, resulting in 98.4% HMF conversion and 89.6% DHMF yield at 150 oC for 5 h in the presence of 2-butanol that simultaneously acted as the hydrogen donor and reaction solvent, which was ascribed to its appropriate specific surface area, pore size and acid-base content. Moreover, a plausible reaction mechanism for the catalytic transfer hydrogenation of HMF into DHMF over MHZ(Zr/Fe=2) was also proposed, in which the basic hydroxyl groups with the aid of acidic zirconium metal centers were considered to be responsible for the pivotal hydride transfer via a six-membered ring structure.

Experimental research on preparation and machining performance of porous electrode in electrical discharge machining

Yi Jiang,Linglei Kong,Jianfeng Yu,Chunjian Hua,Wansheng Zhao 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.12

The present describes a porous electrode for electrical discharge machining (EDM) that can decrease the concentration of corrosion products in the discharge gap. The electrode is prepared by high-temperature sintering of copper particles. A large number of red copper particles become connected together through sintering necks to form a structure with a large number of pores that act as flushing channels. By exploring the preparation method, material, sintering temperature, and holding time, a porous electrode is prepared such that copper particles do not fall off during the discharge process. The flow of the flushing medium is simulated in the porous electrode, and the action of the flushing flow field in the discharge gap on erosion products is identified. In agreement with the simulation results, experimental results for the EDM of the titanium alloy Ti6Al4V show that the material removal rate with a porous electrode is 3 times higher than that for traditional EDM with a solid electrode. Moreover, the electrode wear is lower due to the effective discharge of the corrosion products by the flushing liquid. Experimental results when rough machining a complex semi-closed cavity show that the porous electrode can greatly shorten the machining time by 47 %, which demonstrates that a porous electrode improves the machining of a complex cavity in a titanium alloy.

Adaptive control for small-hole EDM process with wavelet transform detecting method

Yi Jiang,Wansheng Zhao,Xuecheng Xi,Lin Gu 대한기계학회 2012 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.26 No.6

To achieve an efficient small-hole EDM process, an accurate pulse monitoring strategy and a precise control are both required. In order to improve the efficiency and stability of the small-hole drilling process, an adaptive control system with a self-tuning regulator is developed. A high-speed EDM pulses monitoring system based on wavelet transform is implemented to measure the gap status, whose output is adopted as the feedback signals of the adaptive control system. The discharge waveforms are recorded and analyzed. The experimental results demonstrate that the arc pulse ratio during small-hole drilling process is reduced remarkably. The machining efficiency as well as the machining quality is improved significantly.

Consumer Psychological Factors that Affect Chinese Donation Satisfaction and Continuous Donation Intention with Food Banks

Yi Jiang,Jin-Jing Zhao 한국무역연구원 2021 무역연구 Vol.17 No.1

Purpose The goal of this study is to improve the continuous donation behavior of China’s ordinary people to food bank and reduce food waste. Through the survey and measurement of China’s ordinary people’s donation satisfaction and continuous donation intention to the Food Bank;it is possible to find out the consumer psychological factors that affect donation satisfaction and continuous donation intention. Design/Methodology/Approach – A questionnaire survey was conducted for Chinese with experience in food bank donations and data was collected. After excluding bad answers and invalid answers;371 responses were obtained. In order to verify the research hypothesis;this research used structural equation path analysis and hierarchical multiple regression analysis. Findings – Altruistic motivation was found to have no effect on Chinese satisfaction with donations to food banks;while egoistic motivation showed a significant negative impact. The impact of unplanned impulsivity and evaluation sensitivity impulsivity on Chinese donation satisfaction to food banks is significant;but the impact of reward sensitivity impulsivity is not significant. Perspective-taking and empathic concern in consumer empathy have a significant impact on the satisfaction of Chinese donations to food banks. Finally;Chinese satisfaction with donations to food banks was found to have a significant impact on the intention of continuing donations;and only independent self-construal was found to have a moderating effect. Research Implications – This is the first empirical study conducted in the field of food banking in China;combined with consumer psychological factors;and has important academic significance. It also provides valuable references for China’s charitable donations;food distribution industry;and provides new reference ideas for China’s “saving food”.