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green Synthesis of Aryl Thioethers through Cu-catalysed C-S Coupling of Thiols and Aryl Boronic Acids in Water

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Journal of Wuhan University of Technology(Materials Science) 2019年第4期34卷 987-993页

作者： TU Peihua LI Xinhua College of Chemistry and Materials Engineering Wenzhou University

An efficient, practical, highly selective and environmentally benign method is reported for the synthesis of aryl thioethers via the coupling of thiols with aryl boronic acids in the presence of NaOH and a catalytic amount of CuSO4 at 130 ℃ using water as a green solvent. The products were obtained in moderate to excellent yields;more importantly, the use of toxic ligands and solvents was avoided. A broad range of aryl boronic acids and scalable processes make this methodology valuable and versatile for the synthesis of a broad range of aryl sulfides.

关键词： green synthesis Cu-catalysed C-S coupling aryl boronic acids water solvent aryl thioether

Optimal Power Control for Energy Harvesting in green Cognitive Radio Networks

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Journal of Electronic Research and Application 2025年第1期9卷 54-60页

作者： Qiliang Gong Finance Office Lanzhou University of TechnologyLanzhou 730050China

The integration of cognitive radio and energy has enhanced the utilization efficiency of the spectrum and promoted the application of green *** begin with,this paper presents the architecture of green energy-efficient communication and network *** incorporates the distributed network model and the heterogeneous two-tier network model into the green cognitive radio power control and channel allocation *** primary focus of this research lies in energy conservation at the physical *** mitigate the interference with primary users and address the peak constraint in secondary user power allocation,the article analyzes the system model of the cognitive radio network and subsequently elaborates on the dynamic throughput maximization allocation ***,through experimental analysis and verification,the distinctiveness and comprehensiveness of the optimal power control for this subject are illustrated.

关键词： Cognitive radio Spectrum green Throughput Power control

green Distributed Antenna Systems for Smart Communities: A Comprehensive Survey

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China Communications 2019年第11期16卷 70-80页

作者： Haixia Cui Yi Liu School of Physics and Telecommunication Engineering South China Normal University

Smart communities are an emerging communication means in which humans and smart devices will interact with each other and deliver ubiquitous services by exploiting social *** antenna system(DAS),one of the key technologies to realize smart decisions in smart communities,can settle network smart coverage problem and improve system energy/spectrum efficiency *** that energy consumption is an important element for community communications,in this paper,we survey the existing green DAS research for smart *** particular,our investigation covers antenna distribution,system capacity,spectrum efficiency,energy efficiency,and green access ***,we analyze the existing application opportunities and *** survey contributes to better understanding of the challenges and approaches for green DAS in existing smart community networks and further shed novel light on some future research directions.

关键词： smart communities distributed antenna systems spectrum efficiency energy efficiency green communications

An effective and green H2O2/H2O/O3 oxidation method for carbon nanotube to reinforce epoxy resin

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Journal of Materials Science & Technology 2020年第5期40卷 24-30页

作者： Qi Wang Wen Shi Bo Zhu Dang Sheng Su School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Shenyang National Laboratory for Materials Science Shenyang 110016China Jiangsu Gunuo New Materials Technology Go. Ltd.Yancheng 224051China

Facile green oxidation methods are always desired to functionalize carbon nanotubes(CNTs)in the production of advanced CNT/epoxy *** the present work,an optimized H2O2/H2O/O3 oxidation method was developed,and performances of the H2O2/H2O/O3 oxidized CNT in epoxy matrix were tested and compared with that of the H2O/O3 oxidized CNT and the most commonly used concentrated HNO3 oxidized *** physical and chemical characteristics of the obtained oxidized CNTs were systematically characterized via transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS)and *** performances of the obtained composites were explored by tensile tests,impact tests,dynamic mechanical analysis(DMA)and fracture toughness *** was found that the H2O2/H2O/O3 oxidized CNT exhibited all-around overwhelming advantages over the concentrated HNO3 oxidized CNT on reinforcing the epoxy matrix,while the H2O/O3 oxidized CNT only improved the material *** mechanisms for the different methods oxidized CNTs were studied and *** optimized H2O2/H2O/O3 oxidation method makes scaled production possible,avoids environment pollutions,and holds great potentials to replace the most commonly used concentrated HNO3 oxidation method to oxidize CNT during the preparation of the advanced CNT/epoxy composite.

关键词： green oxidation method Carbon nanotube Epoxy composite Mechanical properties Interfacial interaction

green and low temperature synthesis of nanocrystalline transition metal ferrites by simple wet chemistry routes

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Nano Research 2014年第7期7卷 1027-1042页

作者： Stefano Diodati Luciano Pandolfo Andrea Caneschi Stefano Gialanella Silvia Gross Istituto per I'Energetica e le In terfasi IENI-CNR and INSTM UdR di Padova via Marzolo 11-35131 Padova Italy Dipartimento di Scienze Chimiche Universit& degli Studi di Padova via Marzolo 11-35131 Padova Italy Laboratory of Molecular Magnetism LAMM Dipartimento di Chimica e UdR INSTM di Firenze Polo Scientifico Via della Lastruccia 3 50019 Sesto Fiorentino (FI) Italy Dipartimen to di Ingegneria Industriale Universita degli Studi di Tren to via Mesiano 771-38123 Trento Italy

Crystalline and nanostructured cobalt （CoFe2O4）, nickel （NiFe2O4）, zinc （ZnFe2O4） and manganese （MnFe2O4） spinel ferrites are synthesized with high yields, crystallinity and purity through an easy, quick, reproducible and low-temperature hydrothermal assisted route starting from an aqueous suspension of copredpitated metal oxalates. The use of water as a reaction medium is a further advantage of the chosen protocol. Additionally, the zinc spinel is also prepared through an alternative route combining copredpitation of oxalates from an aqueous solution with thermal decomposition under reflux conditions. The nanocrystalline powders are obtained as a pure crystalline phase already at the extremely low tem- perature of 75 ℃ and no further thermal treatment is needed. The structure and microstructure of the prepared materials is investigated by means of X-ray powder diffraction （XRPD）, while X-ray photoelectron spectroscopy （XPS） and inductively coupled plasma-atomic emission spectroscopy （ICP-AES） analyses are used to gain information about the surface and bulk composition of the samples, respectively, confirming the expected stoichiometry. To investigate the effect of the synthesis protocol on the morphology of the obtained ferrites, transmission electron microscopy （TEM） observations are performed on selected samples. The magnetic properties of the cobalt and manganese spinels are also investigated using a superconducting quantum device magnetometer （SQUID） revealing hard and soft ferrimagnetic behavior, respectively.

关键词： ferrites hydrothermal low temperature wet chemistry green

A novel approach to predict green density by high-velocity compaction based on the materials informatics method

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International Journal of Minerals,Metallurgy and Materials 2019年第2期26卷 194-201页

作者： Kai-qi Zhang Hai-qing Yin Xue Jiang Xiu-qin Liu Fei He Zheng-hua Deng Dil Faraz Khan Qing-jun Zheng Xuan-hui Qu Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing Beijing Key Laboratory of Materials Genome Engineering Beijing Laboratory of Metallic Materials and Processing for Modern Transportation School of Mathematics and Physics University of Science and Technology Beijing Chongqing Engineering Technology Research Center for Light Alloy and Processing Department of Physics University of Science and Technology Bannu Kennametal Inc

High-velocity compaction is an advanced compaction technique to obtain high-density compacts at a compaction velocity of ≤10 m/s. It was applied to various metallic powders and was verified to achieve a density greater than 7.5 g/cm^3 for the Fe-based powders. The ability to rapidly and accurately predict the green density of compacts is important, especially as an alternative to costly and time-consuming materials design by trial and error. In this paper, we propose a machine-learning approach based on materials informatics to predict the green density of compacts using relevant material descriptors, including chemical composition, powder properties, and compaction energy. We investigated four models using an experimental dataset for appropriate model selection and found the multilayer perceptron model worked well, providing distinguished prediction performance, with a high correlation coefficient and low error values. Applying this model, we predicted the green density of nine materials on the basis of specific processing parameters. The predicted green density agreed very well with the experimental results for each material, with an inaccuracy less than 2%. The prediction accuracy of the developed method was thus confirmed by comparison with experimental results.

关键词： powder metallurgy high-velocity compaction green density data mining multilayer perceptron

Energy-efficient Virtual Machine Allocation Technique Using Flower Pollination Algorithm in Cloud Datacenter:A Panacea to green Computing

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Journal of Bionic Engineering 2019年第2期16卷 354-366页

作者： Mohammed Joda Usman Abdul Samad Ismail Hassan Chizari Gaddafi Abdul-Salaam Ali Muhammad Usman Abdulsalam Yau Gital Omprakash Kaiwartya Ahmed Aliyu Department of Maths Bauchi State University GadauBauchi 81007Nigeria Department of Computer Science Universiti Teknology MalaysiaSkudai Johor 81310Malaysia School of Computing and Technology Park CampusUniversity of Gloucestershire Cheltenham GL50 4SHUK Department of Computer Science Kwame Nkrumah University of Science and TechnologyKumasi 00233Ghana Department of Maths and Computer Federal College of Education Technical GombeGombe 072158Nigeria Department of Maths Abubakar Tafawa Balewa University BauchiBauchi 81027Nigeria Department of Computer and Information Technology Northumbria UniversityNewcastle NE1SSTUK

Cloud computing has attracted significant interest due to the increasing service demands from organizations offloading computationally intensive tasks to ***,datacenter infrastructure comprises hardware resources that consume high amount of energy and give out carbon emissions at hazardous *** cloud datacenter,Virtual Machines(VMs)need to be allocated on various Physical Machines(PMs)in order to minimize resource wastage and increase energy *** allocation problem is *** finding an exact solution is complicated especially for large-scale *** this con text,this paper proposes an Energy-oriented Flower Pollination Algorithm(E-FPA)for VM allocation in cloud datacenter environments.A system framework for the scheme was developed to enable energy-oriented allocation of various VMs on a *** allocation uses a strategy called Dynamic Switching Probability(DSP).The framework finds a near optimal solution quickly and balances the exploration of the global search and exploitation of the local *** considers a processor,storage,and memory constraints of a PM while prioritizing energy-oriented allocation for a set of *** performed on MultiRecCloudSim utilizing planet workload show that the E-FPA outperforms the Genetic Algorithm for Power-Aware(GAPA)by 21.8%,Order of Exchange Migration(OEM)ant colony system by 21.5%,and First Fit Decreasing(FFD)by 24.9%.Therefore,E-FPA significantly improves datacenter performance and thus,enhances environmental sustainability.

关键词： virtualization green computing cloud datacenter energy optimization

Inhibitory effects of novel green inhibitors on gas hydrate formation

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Chinese Journal of Chemical Engineering 2019年第9期27卷 2107-2117页

作者： Cuiping Tang Deqing Liang Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China Key Laboratory of Gas Hydrate Chinese Academy of SciencesGuangzhou 510640China

Natural gas hydrates easily form in pipelines,causing potential safety issues during oil and gas production and *** gas hydrate inhibitors is one of the most effective methods for preventing gas hydrate formation or ***,some thermodynamic hydrate inhibitors are toxic and harmful to the environment,whereas degradation of kinetic inhibitors is ***,environmentally friendly and easily biodegradable novel green inhibitors have been proposed and *** paper provides a short but systematic review of the inhibitory performance of amino acids,antifreeze proteins,and ionic *** different hydrate formation systems,the influences of the inhibitor type,structure,and concentration on the inhibitory effects are *** mechanism of green inhibitors as kinetic inhibitors is also *** progress described here will facilitate further developments of such green inhibitors for gas hydrate formation.

关键词： Gas hydrate Inhibition green inhibitors Kinetic inhibitors Thermodynamic inhibitors

A Memetic Algorithm With Competition for the Capacitated green Vehicle Routing Problem

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IEEE/CAA Journal of Automatica Sinica 2019年第2期6卷 516-526页

作者： Ling Wang Jiawen Lu the Department of Automation Tsinghua University

In this paper, a memetic algorithm with competition(MAC) is proposed to solve the capacitated green vehicle routing problem(CGVRP). Firstly, the permutation array called traveling salesman problem(TSP) route is used to encode the solution, and an effective decoding method to construct the CGVRP route is presented accordingly. Secondly, the k-nearest neighbor(k NN) based initialization is presented to take use of the location information of the customers. Thirdly, according to the characteristics of the CGVRP, the search operators in the variable neighborhood search(VNS) framework and the simulated annealing(SA) strategy are executed on the TSP route for all solutions. Moreover, the customer adjustment operator and the alternative fuel station(AFS) adjustment operator on the CGVRP route are executed for the elite solutions after competition. In addition, the crossover operator is employed to share information among different solutions. The effect of parameter setting is investigated using the Taguchi method of design-ofexperiment to suggest suitable values. Via numerical tests, it demonstrates the effectiveness of both the competitive search and the decoding method. Moreover, extensive comparative results show that the proposed algorithm is more effective and efficient than the existing methods in solving the CGVRP.

关键词： Capacitated green vehicle routing problem(CGVRP) competition k-nearest neighbor(kNN) local intensification memetic algorithm