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Carbon-coated ni-Co alloy catalysts:preparation and performance for in-situ aqueous phase hydrodeoxygenation of methyl palmitate to hydrocarbons using methanol as the hydrogen donor

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Frontiers of Chemical Science and Engineering 2022年第4期16卷 443-460页

作者： Yinteng Shi Lin.ai Haonan Shi Xiaoyu Gu Yujun Han Jixiang Chen Tianjin Key Laboratory of Applied Catalysis Science and Technology Department of Catalysis Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China

Carbon-coated ni,Co and ni-Co alloy catalysts were prepared by the carbonization of the metal doped resorcinol-formaldehyde resins synthesized by the one-pot extended Stöber *** was found that the introduction of Co remarkably reduced the carbon microsphere *** metallic ni,Co,and ni-Co alloy particles(mainly 10-12 nm)were uniformly distributed in carbon microspheres.A charge transfer from ni to Co appeared in the ni-Co *** with those of metallic ni and Co,the d-band center of the ni-Co alloy shifted away from and toward the Fermi level,*** the in-situ aqueous phase hydrodeoxygenation of methyl palmitate with methanol as the hydrogen donor at 330℃,the decarbonylation/decarboxylation pathway dominated on all *** ni-Co@C catalysts gave higher activity than the ni@C and Co@C catalysts,and the yields of n-pentadecane and n-C6-n-C16 reached 71.6%and 92.6%,*** excellent performance of ni-Co@C is attributed to the electronic interactions between ni and Co and the small carbon *** to the confinement effect of carbon,the metal particles showed high resistance to sintering under harsh hydrothermal *** deactivation is due to the carbonaceous deposition,and the regeneration with CO_(2) recovered the catalyst reactivity.

关键词： Stöber method carbon-coated ni-Co alloy in-situ hydrodeoxygenation methyl palmitate decarbonylation decarboxylation

The equivalents of human blood and spleen dendritic cell subtypes can be generated in vitro from human CD34 ＋ stem cells in the presence of fins-like tyrosine kinase 3 ligand and thrombopoietin

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Cellular & Molecular Immunology 2012年第6期9卷 446-454页

作者： ai Proietto D Mittag AW Roberts n Sprigg L Wu Molecular Immunology Division The Walter and Eliza Hall Institute of Medical Research Parkville Vic. Australia Autoimmunity and Transplantation Division The Walter and Eliza Hall Institute of Medical Research Parkville Vic. Australia Transfusion Research Australian Red Cross Blood Services West Melbourne Vic. 3003 Australia Cancer and Haematology Division The Walter and Eliza Hall Institute of Medical Research Parkville Vic. Australia Tsinghua U niversity-Peking University Joint Center for Life Sciences Tsinghua University School of Medicine Beijing China

Dendritic cells （DCs） are immune cells specialized to capture, process and present antigen to T cells in order to initiate an appropriate adaptive immune response. The study of mouse DC has revealed a heterogeneous population of cells that differ in their development, surface phenotype and function. The study of human blood and spleen has shown the presence of two subsets of conventional DC including the CDlb/c＋ and CD141＋CLEC9A＋ conventional DC （cDC） and a plasmacytoid DC （pDC） that is CD304＋CD123＋. Studies on these subpopulations have revealed phenotypic and functional differences that are similar to those described in the mouse. In this study, the three DC subsets have been generated in vitrofrom human CD34＋ precursors in the presence of fins-like tyrosine kinase 3 ligand （FIt3L） and thrombopoietin （TPO）. The DC subsets so generated, including the CDlb/c＋ and CLEC9A＋ cDCs and CD123 ＋ pDCs, were largely similar to their blood and spleen counterparts with respect to surface phenotype, toll-like receptor and transcription factor expression, capacity to stimulate T cells, cytokine secretion and cross-presentation of antigens. This system may be utilized to study aspects of DC development and function not possible in vivo.

关键词： dendritic cells fms-like tyrosine kinase 3 ligand thrombopoietin

Integration of Fog Computing for Health Record Management Using Blockchain Technology

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Computers, Materials & Continua 2022年第5期71卷 4135-4149页

作者： Mesfer ai Duhayyim Fahd n.Al-Wesabi Radwa Marzouk Abdalla Ibrahim Abdalla Musa noha negm Anwer Mustafa Hilal Manar Ahmed Hamza Mohammed Rizwanullah Department of natural and Applied Sciences College of Community AflajPrince Sattam Bin Abdulaziz UniversitySaudi Arabia Department of Computer Science College of Science&Art at MahayilKing Khalid UniversitySaudi Arabia&Faculty of Computer and ITSana’a UniversityYemen Department of Information Systems College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversitySaudi Arabia&Department of MathematicsFaculty of ScienceCairo UniversityGiza12613Egypt Department of Computer Science College of ComputerQassim UniversityBuraydahSaudi Arabia Department of Computer Science King Khaled UniversityKSA&Faculty of ScienceDepartment of Mathematics and Computer ScienceMenoufia UniversityEgypt Department of Computer and Self Development Preparatory Year DeanshipPrince Sattam Bin Abdulaziz UniversityAlKharjSaudi Arabia

Internet of Medical Things (IoMT) is a breakthrough technologyin the transfer of medical data via a communication system. Wearable sensordevices collect patient data and transfer them through mobile internet, thatis, the IoMT. Recently, the shift in paradigm from manual data storage toelectronic health recording on fog, edge, and cloud computing has been *** advanced computing technologies have facilitated medical services withminimum cost and available conditions. However, the IoMT raises a highconcern on network security and patient data privacy in the health caresystem. The main issue is the transmission of health data with high security inthe fog computing model. In today’s market, the best solution is blockchaintechnology. This technology provides high-end security and authenticationin storing and transferring data. In this research, a blockchain-based fogcomputing model is proposed for the IoMT. The proposed technique embedsa block chain with the yet another consensus (YAC) protocol building securityinfrastructure into fog computing for storing and transferring IoMT data inthe network. YAC is a consensus protocol that authenticates the input datain the block chain. In this scenario, the patients and their family membersare allowed to access the data. The empirical outcome of the proposedtechnique indicates high reliability and security against dangerous *** major advantages of using the blockchain model are high transparency,good traceability, and high processing speed. The technique also exhibitshigh reliability and efficiency in accessing data with secure transmission. Theproposed technique achieves 95% reliability in transferring a large number offiles up to 10,000.

关键词： Fog computing IoMT block chain YAC security IoT consensus protocol

Almost Sure Convergence and Complete Convergence for the Weighted Sums of Martingale Differences

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Wuhan University Journal of natural Sciences 1999年第3期4卷 278-284页

作者： Deng ai-jiao Liu Jing-jun Wuhan University College of Mathematical and Computer Sciences Wuhan China (GRID:grid.49470.3e) (ISNI:***)

Let {(D n, FFFn),n/->1} be a sequence of martingale differences and {a ni, 1≤i≤n,n≥1} be an array of real constants. Almost sure convergence for the row sums ?i = 1n ani D1\sum\limits_{i = 1}^n {a_{ni} D_1 } are discussed. We also discuss complete convergence for the moving average processes underB-valued martingale differences assumption.

关键词： complete convergence almost sure convergence weighted sums, martingale differences moving average processes

Four-dimensional matrix Walsh transform for lossless compression of color video

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The Journal of China Universities of Posts and Telecommunications 2010年第3期17卷 123-128页

作者： LI Yu CHEn He-xin SAnG ai-jun FEnG Hua College of Communication Engineering Jilin University Changchun 130025 China School of Electrical and Information Engineering Changchun Institute of Technology Changchun 130012 China

This article presents a coding method for the lossless compression of color video. In the proposed method, four-dimensional matrix Walsh transform （4D-M-Walsh-T） is used for color video coding. The whole n frames of a color video sequence are divided into ＇3D-blocks＇ which are image width （row component）, image height （column component）, image width （vertical component） in a color video sequence, and adjacency （depth component） of n frames （Y, U or V） of the video sequence. Similar to the method of 2D-Walsh transform, 4D-M-Walsh-T is 4D sub-matrices, and the size of each sub-matrix is n. The method can fully utilize correlations to encode for lossless compression and reduce the redundancy of color video, such as adjacent pixels in one frame or different frames of a video at the same time. Experimental results show that the proposed method can achieve higher lossless compression ratio （CR） for the color video sequence.

关键词： 4D-M-Walsh-T lossless compression compression ratio

The Synthesis and Characterization of High Molecular Weight Poly(phenylene sulfide/ether)

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Chinese Chemical Letters 2006年第10期17卷 1373-1376页

作者： ai Qun GU Mei Ju XIE Zi Li YU Institute of Materials Science ＆ Technology Analytical ＆ Testing Center Sichuan University Chengdu 610064

Poly（phenylene sulfide/ether）（PPSE） was synthesized from 4,4＇-dihydroxydiphenyl sulfide and 4,4＇-dichlorodiphenyl sulfide in solution by nucleophilic substitution reaction. The resulting polymer was characterized by viscosity measurement, elemental analysis, FT-IR, ^1H nMR, X-ray diffraction and thermal analysis. The results showed that the viscosities of the resulting polymer were above 0.68 dL/g, and the linear chain structure of product was confirmed. PPSE had the same reflex indices as poly（p-phenylene sulfide）, an orthorhombic crystalline with unit cell a=0.853, b=0.562, c=1.026nm. The melting temperature, glass transition temperature and initial decomposition temperature were found to be 228℃, 85℃ and 325℃, respectively. The product was soluble in common organic solvents such as nMP, n, n＇-dimethylformamide, n, n＇-dimethylacetamide and 1,2-dichloroethane.

关键词： Poly(phenylene sulfide/ether) (PPSE) synthesis characterization.

Metamorphic Rock-hosted Disseminated Gold Deposits——A Case Study of the Xiaotongjiapuzi Gold Depositof Eastern Liaoning

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Acta Geologica Sinica(English Edition) 1999年第4期73卷 429-437页

作者： LIU Guoping ai Yongfu FEnG Kezhu ZHAnG Zhimin Beijing Institute of Geology for Mineral Resources CNNC Beijing 100012 Department of Geology Peking University Beijing 100871 no. 103 Geological Party Liaoning Bureau of Geological Exploration CNNC Dandong Liaoning 118008

The Xiaotongjiapuzi gold deposit occurs in a Palaeoproterozoic rift accretionary terrane in eastern Liaoning and is hosted by a carbonate formation of the Dashiqiao Formation, Liaohe Group. The metamorphic grade of the host rock is low amphibolite-high greenschist facies. Gold, which is mainly invisible, is distributed in pyrite and arsenopyrite. The grains of Au-bearing sulphide minerals are fine, ranging from 0.0 n to 1 mm. The wall-rock alterations are characterized by low-temperature silification, hydro-sericitization, sericitization and carbonatization. The homogenization temperatures of the fluid inclusions in quartz closely associated with gold mineralization range from 140 to 240°C. The metallogenic age represented by the Ar-Ar isotopic age of sericite is 167 Ma. Comparisons and studies show that the Xiaotongjiapuzi gold deposit can be classified as the submicron-sized disseminated deposit (analogous to the Carlin-type) hosted in metamorphic rocks.

关键词： disseminated gold deposit eastern Liaoning metamorphic rock

The preparation of nitrogen-doped TiO_2 nanocrystals with exposed {001} facets and their visible-light photocatalytic performances

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Chinese Science Bulletin 2014年第18期59卷 2199-2207页

作者： Huiying ai Jianwen Shi Jianwei Chen Minglai Fu Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of Sciences

Anatase TiO2with exposed{001}facets has been deepgoingly studied for optimizing its photocatalytic *** this study,we synthesized n-doped TiO2 nanocrystals with exposed{001}facets by sol–gel method and solvothermal method,*** physical and chemical properties of as-synthesized samples,such as morphology,crystal phase,surface elements composition,porous structure,specific surface area,and optical response,were characterized in *** photocatalytic performances of all samples were evaluated by photocatalytic decoloration of methylene blue under visible-light irradiation(k[420 nm).The results showed that the as-prepared samples present high visible-light photocatalytic performances,which can be ascribed to the excellent crystallization,the enhancement of absorbance in the visible-light region,and the strong adsorption performance,and calcination treatment is helpful to further improve the visible-light photocatalytic performance of n-doped TiO2 nanocrystals with exposed{001}facets.

关键词： TiO2纳米晶光催化性能可见光照射氮掺杂晶面晶带比表面积光催化活性

Influence of temperature on tunneling-enhanced recombination in Si based p–i–n photodiodes

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Journal of Semiconductors 2014年第8期35卷 10-14页

作者： P.Dalapati n.B.Manik A.n.Basu Condensed Matter Physics Research Center Department of Physics Jadavpur University

We investigate the dominant dark current transport mechanism in Si based p-i-n photodiodes, namely, BPW 21R, SFH 205FA and BPX 61 photodiodes in the temperature range of 350 to 139 K. The forward current- voltage characteristics of these photodiodes are explained via the tunneling enhanced recombination model, which gives a quantitative description of the electronic mechanism in the p-i-n junction photodiodes. The observed tem- perature dependence of the saturation current and the diode ideality factor of these devices agree well with theo- retical predictions; the analysis also indicates the importance of doping for enhancement of tunneling. The present study will be helpful in applying the devices at low temperature ambience.

关键词： photodiode low temperature ideality factor reverse saturation current tunneling energy