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Bifunctional core–shell co-catalyst for boosting photocatalytic CO_(2) reduction to CH_(4)

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Nano Research 2024年第3期17卷 1259-1266页

作者： Fangxu Dai Mingming Zhang Jishu Han Zhenjiang Li Shouhua Feng Jun Xing Lei Wang Key Laboratory of Eco-chemical engineering Ministry of EducationCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China college of Materials science and engineering Qingdao University of Science and TechnologyQingdao 266042China college of Environment and Safety engineering Qingdao University of Science and TechnologyShandong Engineering Research Center for Marine Environment Corrosion and Safety ProtectionQingdao 266042China

Solar-light-driven CO_(2) reduction CO to CH_(4) and C2H6 is a complex process involving multiple elementary reactions and energy ***,achieving high CH_(4) activity and selectivity remains a significant ***,we integrate bifunctional Cu2O and Cu-MOF(MOF=metal-organic framework)core–shell co-catalysts(Cu2O@Cu-MOF)with semiconductor TiO_(2).Experiments and theoretical calculations demonstrate that Cu2O(Cu+facilitates charge separation)and Cu-MOF(Cu2+improves the CO_(2) adsorption and activation)in the core–shell structure have a synergistic effect on photocatalytic CO_(2) reduction,reducing the formation barrier of the key intermediate*COOH and**** photocatalyst exhibits high CH_(4) yield(366.0μmol·g^(-1)·h^(-1)),efficient electron transfer(3283μmol·g^(-1)·h^(-1))and hydrocarbon selectivity(95.5%),which represents the highest activity of Cu-MOF-based catalysts in photocatalytic CO_(2) reduction *** work provides a strategy for designing efficient photocatalysts from the perspective of precise regulation of components.

关键词： bifunctional co-catalyst core–shell photocatalytic CO_(2)reduction

E-voting system using cloud-based hybrid blockchain technology

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Journal of Safety science and Resilience 2024年第1期5卷 102-109页

作者： Beulah Jayakumari S Lilly Sheeba Maya Eapen Jani Anbarasi Vinayakumar Ravi A.Suganya Malathy Jawahar Department of information Technology Tagore engineering college Chennai India School of Computer science and engineering SRM Institute of science and Technology Ramapuram ChennaiIndia Department of information Technology Jerusalem college of engineering ChennaiIndia School of Computer science and engineering Vellore Institute of Technology Chennai India Center for Artificial Intelligence Prince Mohammad Bin Fahd UniversityKhobarSaudi Arabia Leather Process Technology Division CSIR-Central Leather Research Institute ChennaiIndia

With the invention of Internet-enabled devices,cloud and blockchain-based technologies,an online voting system can smoothly carry out election *** pandemic situations,citizens tend to develop panic about mass gatherings,which may influence the decrease in the number of *** urges a reliable,flexible,transparent,secure,and cost-effective voting *** proposed online voting system using cloud-based hybrid blockchain technology eradicates the flaws that persist in the existing voting system,and it is carried out in three phases:the registration phase,vote casting phase and vote counting phase.A timestamp-based authentication protocol with digital signature validates voters and candidates during the registration and vote casting *** smart contracts,third-party interventions are eliminated,and the transactions are secured in the blockchain ***,to provide accurate voting results,the practical Byzantine fault tolerance(PBFT)consensus mechanism is adopted to ensure that the vote has not been modified or ***,the overall performance of the proposed system is significantly better than that of the existing *** performance was analyzed based on authentication delay,vote alteration,response time,and latency.

关键词： E-voting Cloud Blockchain Smart contract Consensus mechanism

Threshold control in VCSELs by proton implanted depth

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Optoelectronics Letters 2011年第4期7卷 263-265页

作者：赵红东孙梅王伟马连喜刘会丽李文超刘琦 college of information engineering Hebei University of Technology Department of Physics Blinn College

The proton implantation is one of key procedures to confine the current diffusion in vertical cavity surface emitting lasers(VCSELs),in which the proton implanted depth and profile are main *** characteristics of VCSELs with various proton implanted depths are studied after optical,electrical and thermal fields have been simulated self-consistently in three *** is found that for VCSELs with confinement radius of 2 mm,increasing proton implanted depth can reduce the injected current threshold power and enhance the laser temperature in active *** results also indicate that there are optimal values for current aperture in proton implanted *** minimum injected current threshold can be achieved in VCSELs with proton implantation near the active region and confinement radius of 1.5 mm,while the VCSELs with proton implantation in the middle of p-type distributed Bragg reflectors(DBRs) and confinement radius of 2.5 mm can realize the minimum temperature.

关键词： Protons

Superplasticity and superplastic instability of AZ31B magnesium alloy sheet

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中国有色金属学会会刊：英文版 2006年第2期16卷 327-332页

作者：汪凌云宋美娟刘饶川 college of Materials science and engineering Chongqing University Chongqing 400044 China college of Materials science and engineering Chongqing University Chongqing 400044 China Department of Mechanical Engineering Chongqing University of Science and Technology Chongqing 400050 China Department of Mechanical engineering Chongqing University of Science and Technology Chongqing 400050 China

Superplastic deformation mechanism of AZ31B magnesium alloy sheet was investigated. Maximum elongation of 216% and strain rate sensitivity of 0.36 were obtained at 723 K and a strain rate of 1×10?3s?1. It is found that dynamic recrystallization occurs at the early deformation stage, and that grain boundary sliding is the dominant deformation mode of superplastic AZ31B sheet, whose fracture is due to the growth and interlinkage of cavities nucleated at grain boundary. A cavity growth model was established, and damage characteristic parameters as well as the critical value of damage variable were identified so as to provide a theoretical ground on which the plastic forming technology of magnesium alloy sheet can be optimized.

关键词：镁合金超塑性应变敏感性孔穴损伤

Pt-surface oxygen vacancies coupling accelerated photo-charge extraction and activated hydrogen evolution

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Nano Research 2023年第4期16卷 4736-4741页

作者： Fangxu Dai Mingming Zhang Mingzhong Mi Zhenjiang Li Jun Xing Lei Wang Key Laboratory of Eco-chemical engineering Ministry of EducationCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China college of Materials science and engineering Qingdao University of Science and TechnologyQingdao 266042China college of Environment and Safety engineering Qingdao University of Science and TechnologyShandong Engineering Research Center for Marine Environment Corrosion and Safety ProtectionQingdao 266042China

Semiconductors-based heterogeneous photocatalytic water splitting has been extensively studied,but it still remains challenging to accelerate the separation of electron-hole pairs and facilitate the reaction *** we report a general strategy to fabricate highly efficient Pt/TiO_(2)photocatalyst by coupling the Pt co-catalysts and surface oxygen vacancies(VO)of TiO_(2).TiO_(2)was pre-modified with alkali or alkaline earth metals ion solutions,which produce a large number of surface hydroxyl on TiO_(2).Subsequently,the photodeposited Pt sub-nanoparticles substitute surface hydroxyl and induce surface VO on TiO_(2).The coupling of Pt and surface VO on TiO_(2)can accelerate the extraction of photo-charges through the interaction of Pt-VO-Ti bonds and reduce the hydrogen evolution barrier,thereby promoting the photocatalytic *** synthesized Pt-VO-TiO_(2)sample exhibits a photocatalytic hydrogen evolution activity as high as 1.5 L·g^(−1)·h^(−1),which is 2.2 times that of traditional Pt/TiO_(2).Our findings indepth understand the synergistic effect of co-catalysts and defects on photocatalysis and open up new possibilities for achieving robust photocatalytic water splitting.

关键词： oxygen vacancies co-catalyst surface hydroxyl photocatalytic hydrogen evolution reaction(HER)

Preparation and photocatalytic performance of ZnO/ZnGa_2O_4 composite microspheres

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Journal of Central South University 2016年第12期23卷 3092-3099页

作者：张丽戴超华张秀秀刘又年阎建辉 college of Chemistry and Chemical engineering Hunan Institute of Science and Technology college of Chemical engineering Xiangtan University School of Chemistry and Chemical engineering Central South University

ZnO/ZnGa_2O_4 composite microspheres with heterojunction were successfully synthesized by one-pot hydrothermal *** samples were characterized by TG/DTA,XRD,TEM,HRTEM,UV-vis DRS,FL and BET *** results indicated the as-prepared samples showed better degree of crystalline and large specific surface *** photocatalytic activity was evaluated by degradation of methyl orange with the concentration of 50 mg/L under the irradiation of simulated *** effects of molar ratio of Zn to Ga and calcination temperature on the photocatalytic activity were investigated in *** results showed that the highest photocatalytic degradation efficiency was observed at the molar ratio of Zn to Ga of 1:0.5 in the starting materials and the calcination temperature of 400 °*** maximum photocatalytic degradation rate of MO was 97.1% within 60 min under the simulated sunlight irradiation,which is greatly higher than that of ZnO and ZnGa_2O_4.

关键词： ZnO/ZnGa2O4 photocatalytic performance microspheres simulated sunlight

Changes in wheat protein digestibility and allergenicity: role of Pediococcus acidilactici XZ31 and yeast during dough fermentation

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Food science and Human Wellness 2023年第6期12卷 2381-2389页

作者： Wenhui Fu Chen Chen Chenglong Liu Sha Tao Wentong Xue Tianjin Key Laboratory of Food science and Health School of MedicineNankai UniversityTianjin 300071China college of Food science and Nutritional engineering China Agricultural UniversityBeijing 100083China college of information and Electrical engineering China Agricultural UniversityBeijing 100083China

Wheat flour,as the most important source of food globally,is one of the most common causative agents of food *** study aimed to investigate the effects of fermentation on wheat protein digestibility and *** digestibility were evaluated using the sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis and enzyme-linked immunosorbent *** effect of protein on intestinal permeability was investigated by Caco-2 cell ***-culture fermentation with Pediococcus acidilactici XZ31 and yeast leads to improvement in digestibility of wheat protein compared to single strain *** leads to a decrease in albumin/globulin antigenicity and an increase in gluten R5 reactivity,with the most significant changes in the co-culture *** strengthen the decrease of protein antigenicity and counteracts the difference in antigenicity induced by fermentation between ***,pretreatment with *** XZ31 reduces the amount of allergens across Caco-2 monolayer and attenuates the gluten-induced increase in permeability of Caco-2 cell monolayer by reducing actin polymerization and villous ***-culture fermentation reduces gluten-induced cell monolayer damage to a greater extent than *** XZ31 *** results gives valuable insight into the effects of *** XZ31 fermentation on the allergenicity and toxicity of wheat proteins,which contribute to promoting the application of multi-strain leavening agent in hypoallergenic and gluten-free wheat products.

关键词： Fermentation Digestion Wheat allergen In vitro model Allergenicity

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An Access Control Scheme Using Heterogeneous Signcryption for IoT Environments

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Computers, Materials & Continua 2022年第3期70卷 4307-4321页

作者： Insaf Ullah Hira Zahid Fahad Algarni Muhammad Asghar Khan Hamdard Institute of engineering and Technology Islamabad44000Pakistan Department of information Technology Abbottabad University of Science and TechnologyAbbottabadPakistan college of Computing and information Technology The University of BishaBishaSaudi Arabia

When the Wireless Sensor Network(WSN)is combined with the Internet of Things(IoT),it can be employed in a wide range of applications,such as agriculture,industry 4.0,health care,smart homes,among *** the big data generated by these applications in Cloud Servers(CSs),requires higher levels of authenticity and confidentiality during communication conducted through the *** is one of the most promising approaches nowadays for overcoming such obstacles,due to its combined nature,i.e.,signature and encryption.A number of researchers have developed schemes to address issues related to access control in the IoT literature,however,the majority of these schemes are based on homogeneous *** will be neither adequate nor practical for heterogeneous IoT *** addition,these schemes are based on bilinear pairing and elliptic curve cryptography,which further requires additional processing time and more communication overheads that is inappropriate for real-time ***,this paper aims to solve the above-discussed issues,we proposed an access control scheme for IoT environments using heterogeneous signcryption scheme with the efficiency and security hardiness of hyperelliptic *** the security services such as replay attack prevention,confidentiality,integrity,unforgeability,non-repudiations,and forward secrecy,the proposed scheme has very low computational and communication costs,when it is compared to existing *** is primarily because of hyperelliptic curve lighter nature of key and other *** AVISPA tool is used to simulate the security requirements of our proposed scheme and the results were under two backbends(Constraint Logic-based Attack Searcher(CL-b-AtSER)and On-the-Fly Model Checker(ON-t-FL-MCR))proved to be SAFE when the presented scheme is coded in HLPSL *** scheme was proven to be capable of preventing a variety of attacks,including confidentiality,integrity,unforge

关键词： Internet of Things(IoT) access control big data heterogeneous signcryption

Effects of Y on the Microstructure, Mechanical and Bio-corrosion Properties of Mg-Zn-Ca Bulk Metallic Glass

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Journal of Materials science & Technology 2014年第12期30卷 1255-1261页

作者： Jingfeng Wang Yang Li Song Huang Yiyun Wei Xingfeng Xi Kaiyong Cai Fusheng Pan National engineering Research Center for Magnesium Alloys College of Materials Science and Engineering Chongqing University China Academy of engineering Physics college of Bioengineering Chongqing University

The micro-alloying effects of Y on the microstructure, mechanical properties, and bio-corrosion behavior of Mg69-xZn27Ca4Yx（x= 0, 1, 2 at.%） alloys were investigated through X-ray diffraction, compressive tests,electrochemical treatments, and immersion tests. The Mg69Zn27Ca4 alloy was found to be absolutely amorphous, and its glass-forming ability decreased with the addition of Y. The Mg68Zn27Ca4Y1 alloy exhibited an ultrahigh compressive strength above 1010 MPa as well as high capacity for plastic strain above 3.1%.Electrochemical and immersion tests revealed that these Y-doped MgeZ neC a alloys had good bio-corrosion resistance in simulated body fluid（SBF） at 37℃. The results of the cytotoxicity test showed high cell viabilities for these alloys, which means good bio-compatibility.

关键词： Mg alloy Microstructure Mechanical properties Bio-corrosion resistance Bio-compatibility