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LDH-based nanomaterials for photocatalytic applications:A comprehensive review on the role of bi/trivalent cations, anions,morphology, defect engineering, memory effect, and heterojunction formation

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Journal of Energy Chemistry 2023年第9期84卷 242-276页

作者： Azmat Ali Khan Muhammad Tahir Nazish Khan Baluchistan University of Information Technology Engineering and Management Sciences(BUITEMS)P.O.Box 87100QuettaPakistan Chemical and petroleum Engineering Department UAE UniversityP.O.Box 15551Al AinUnited Arab Emirates The University of Agriculture Swat P.O.Box 19040Pakistan

Using sunlight to drive chemical reactions via photocatalysis is paramount for a sustainable *** several photocatalysts,employing layered double hydrides(LDH) for photocatalytic application is most straightforward and desirable owing to their distinctive two-dimensional(2D) lamellar structure and optical *** article reviews the advancements in bimetallic/trimetallic LDHs and various strategies to achieve high efficiency toward an outstanding performing ***,the tuning of LDH components that control the electro nic and structural properties is *** tu ning obtained through the adoption,combination,and incorporation of different cations and anions is also *** progress of modification methods,such as the adoption of different morphologies,delamination,and defect engineering towards enhanced photocatalytic activities,is discussed in the *** band engineering,structural characteristics,and redox tuning are further deliberated to maximize solar energy harvesting for different photocatalytic ***,the progress obtained in forming hierarchical heterostructures through hybridization with other semiconductors or conducting materials is systematically disclosed to get maximum photocatalytic ***,the structural changes during the in-situ synthesis of LDH and the stability of LDH-based photocatalysts are *** review also summarizes the improvements in LDH properties obtained through modification tactics and discusses the prospects for future energy and environmental applications.

关键词： LDH properties potential photocatalyst photocatalytic application photocatalytic properties Improvement strategies

A NoVEL SLIGHTLY CoMpRESSIBLE MoDEL FoR LoW MACH NUMBER pERFECT GAS FLoW CALCULATIoN

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Acta Mechanica Sinica 2002年第3期18卷 193-208页

作者：邓小刚庄逢甘 China Aerodynamics Research and Development Center P.O.Box 211 Mianyang Sichuan China 621000 Chinese Aerodynamic Society P.O.Box 849 Beijing China 100830

By analyzing the characteristics of low Mach number perfect gas flows, a novel Slightly Compressible Model (SCM) for low Mach number perect gas flows is derived. In view of numerical calculations, this model is proved very efficient, for it is kept within thep-v frame but does not have to satisfy the time consuming divergence-free condition in order to get the incompressible Navier-Stokes equation solution. Writing the equations in the form of conservation laws, we have derived the characteristic systems which are necessary for numerical calculations. A cell-centered finite-volume method with flux difference upwind-biased schemes is used for the equation solutions and a new Exact Newton Relaxation (ENR) implicit method is developed. Various computed results are presented to validate the present model. Laminar flow solutions over a circular cylinder with wake developing and vortex shedding are presented. Results for inviscid flow over a sphere are compared in excellent agreement with the exact analytic incompressible solution. Three-dimensional viscous flow solutions over sphere and prolate spheroid are also calculated and compared well with experiments and other incompressible solutions. Finally, good convergent performances are shown for sphere viscous flows.

关键词： slightly compressible flow numerical simulations low Mach number flow calculations Newton iteration relaxation algorithm

HEAT-RESISTANT,pYRIDINE-BASED poLYAMIDES CoNTAINING ETHER AND ESTER UNITS WITH IMpRoVED SoLUBILITY

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Chinese Journal of polymer Science 2010年第1期28卷 29-37页

作者： Hassan Ebadi Shahram Mehdipour-Ataei Islamic Azad University of Shahreza P.O.Box 81145-311 ShahrezaIsfahanIran Iran polymer and petrochemical Institute P.O.Box 14965/115 TehranIran

A diamine containing ether and ester units, as basic monomer for the preparation of polyamides, was prepared via three consecutive reactions. Nucleophilic substitution reaction of 1,4-dihydroxy benzene with 4-nitrobenzoyl chloride produced 4-hydroxyphenyl 4-nitrobenzoate （HpNB）. Reduction of nitro groups to amino groups using Fe and HC1 resulted in preparation of 4-hydroxyphenyl 4-aminobenzoate （HpAB）. The diamine was synthesized through nucleophilic substitution reaction of HpAB with 2,6-dichloropyridine. The precursors and diamine were fully characterized by common methods, and the diamine was polycondensed with different diacid chlorides in the presence of an acid scavenger to prepare new polyamides. The polyamides were characterized, and their physical properties including thermal stability and behavior, inherent viscosity and solubility were studied.

关键词： polyamide polycondensation Diamine Ester Ether.

purification,application and current market trend of natural graphite:A review

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International Journal of Mining Science and Technology 2019年第5期29卷 671-689页

作者： Allah D.Jara Amha Betemariam Girma Woldetinsae Jung Yong Kim School of Materials Science and Engineering Jimma Institute of TechnologyJimma UniversityJimma P.O.Box 378Ethiopia Defense Engineering College Bishoftu P.O.Box 1041Ethiopia The Ministry of Mines Petroleum and Natural GasAddis Ababa P.O.Box 486Ethiopia School of Chemical Engineering Jimma Institute of TechnologyJimma UniversityJimma P.O.Box 378Ethiopia

Graphite has a stacked planar sp2-hybridized C6 ring structure,displaying a polymorphism with rhombohedral,hexagonal,and *** on its structure-property relationship,it affords a variety of technologically innovative applications or performances in industries,such as lithium-ion batteries,fuel cells,two dimensional graphene,water purification,electronics,fiber optics,spintronics,refractories,electrical products,electric vehicles,*** monetary value of graphite depends largely on carbon content and flake ***,the physical separation of graphite from its ore body is known to be very expensive,energy intensive and ***,this study extensively describes a current purification method for producing high-quality graphite material with impurities reaching about 10–100 mg/kg,attracting a lot of end *** also describes the potential applications of graphite materials and identifies the future scope of a new market,depending on material ***,the current and future graphite-mining countries are investigated in details.

关键词： Graphite purification Graphene Lithium-ion battery Market Technology

phase-controlled atom-photon entanglement in a three-level Λ-type closed-loop atomic system

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Chinese physics B 2013年第6期22卷 211-217页

作者： Ali Mortezapour Zeinab Kordi Mohammad Mahmoudi Institute for Advanced Studies in Basic Sciences P.O.Box 45195-159ZanjanIran physics Department University of ZanjanP.O.Box 45195-313ZanjanIran

We study the entanglement of dressed atom and its spontaneous emission in a three-level A-type closed-loop atomic system in a multi-photon resonance condition and beyond it. It is shown that the von Neumann entropy in such a system is phase-dependent, and it can be controlled by either the intensity or relative phase of applied fields. It is demonstrated that for the special case of the Rabi frequency of applied fields, the system is disentangled. In addition, we take into account the effect of Doppler broadening on the entanglement and it is found that a suitable choice of laser propagation direction allows us to obtain the steady state degree of entanglement （DEM） even in the presence of the Doppler effect.

关键词： entanglement quantum entropy closed-loop system

optical nonlinearities of tetracarbonyl-chromium triphenyl phosphine complex

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Chinese physics B 2017年第4期26卷 214-218页

作者： M D Zidan A W Allaf A Allahham A AL-Zier Department of physics Atomic Energy CommissionP.O.Box 6091DamascusSyria Department of Chemistry Atomic Energy CommissionP.O.Box 6091DamascusSyria

The new tetracarbonyl - chromium-triphenyl phosphine complex was synthesized and characterized using ultraviolet（UV）-visible,Fourier transform infrared（FTIR）,and nuclear magnetic resonance（NMR） *** characterization results confirm the molecular structure of the new *** z-scan measurements were done by diode laser[continuous wave（CW）]to estimate the nonlinear optical parameter（X^3）.The results led to calculate three parameters：the groundstate cross sections（σ_g）,the excited-state cross sections（σ_（ex））,and thermo-optic coefficient of the new *** study indicated that our complex is a suitable for photonic applications.

关键词： tetra carbonyl-chromium triphenyl phosphine Z-scan technique nonlinear optical materials

Blockchain Mobile Wallet with Secure offline Transactions

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Computers, Materials & Continua 2023年第5期75卷 2905-2919页

作者： Raed Saeed Rasheed Khalil Hamdi Ateyeh Al-Shqeerat Ahmed Salah Ghorab Fuad Salama Abuowaimer Aiman Ahmed AbuSamra Faculty of Engineering Islamic University of GazaP.O.Box 108GazaPalestine Department of Computer Science College of ComputerQassim UniversityP.O.Box 52211BuraydahSaudi Arabia University College of Applied Sciences P.O.Box 1415GazaPalestine palestine Technical College P.O.Box 6037Deir ElBalahPalestine

There has been an increase in the adoption of mobile payment systems worldwide in the past few ***,poor Internet connection in rural regions continues to be an obstacle to the widespread use of such *** top of that,there are significant problems with the currently available offline wallets;for instance,the payee cannot verify the number of coins received without access to the ***,it has been demonstrated that some existing systems are susceptible to false token generation,and some do not even permit the user to divide the offline token into smaller portions to be used as *** paper proposes a blockchainbased wallet system that provides a secure mobile payment service even if a user cannot access a reliable Internet *** approach relies on Bluetooth and digital signatures to establish and build a trust connection between the *** proposed solution overcomes the main limitations of existing systems that use offline transactions,such as the generation of fake offline tokens and the indivisibility of offline *** user buys offline Tokens(oTs)from a server called an offline Token Manager(oTM)to use them later to perform offline *** mobile device must store a single,signed offline token transaction to prevent fake *** the other hand,all offline transactions will be kept as a history in a particular local ***,when the receiver becomes online,it will send a convert request to the oTMto change the value of the oTs to the appropriate amount in real *** step requires a connection to the *** evaluate the effectiveness of the system,the Solidity programming language was used to develop a smart contract on the Ethereum blockchain with a backend application programming interface(ApI)and an android mobile *** proposed method has an advantage over other prominent wallets.

关键词： Mobile wallet blockchain smart contracts digital signature

Model for Heat pinch in Reversed Magnetic Shear Tokamak plasmas

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Chinese physics Letters 1998年第10期15卷 721-723页

作者： QIU Xiao-ming WANG Ai-ke Southwestern Institute of physics P.O.Box 432Chengdu 610041

A simple model is proposed to explain the recent experiment in TFTR and the more recent one in *** the model the significant reduction of effective thermal diffusivities of ions and electrons(xieff and xeeff)is attributed to the inward flows of drift wave energy,induced by the synergistic effects of the reversed magnetic shear and E X B velocity shear,where E is due to ion pressure *** results demonstrate the predictions of the present model,in particular,the numerical results for x_(i)^(eff) are in good agreement with experimental trents.

关键词： reversed plasma synergistic

Sprayformed Hot Work Steels for Rapid Tooling

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Journal of Materials Science & Technology 2003年第Z1期19卷 169-172页

作者： Yunfeng Yang Simo-pekka Hannula VTT Industrial Systems p.o.box 1703 FIN-02044 VTT Finland VTT Industrial Systems P.O.BOX 1703 FIN-02044 VTT Finland

The present work compares microstructures of hot work steels made by different processes, that is, by sprayforming,by casting, and a commercially supplied H13 steel. Material benefits are recognized by sprayforming hot working tools such as die inserts for hot forging. The sprayformed hot work steels present a fine and homogeneous microstructure,which implies that, at a similar toughness level, the sprayformed steel can be higher alloyed, so that the thermal fatigue and wear resistance at elevated temperatures can be improved. A series of steels with higher vanadium content than commercial hot work steels are developed. There are no segregation and carbide network problems usually encountered in conventional ingot/forging processed high-vanadium steels. Microstructure and hardness of the new sprayformed steels are studied under different heat treatment conditions. It is justified that these sprayformed steels can be directly used for tooling without high temperature hardening. Sprayforming the tool steels onto a precision ceramic mould is demonstrated to extend the technoeconomical benefits, so that a net shape production tool can be rapidly *** of the rapid tooling process are also discussed.

关键词： Rapid tooling, Sprayforming, Hot working steel, Die insert