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first-principles study of structural,electronic,and optical properties of cubic InAs_xN_yP_(1-x-y) triangular quaternary alloys

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Chinese Physics B 2017年第1期26卷 425-432页

作者： I Hattabi A Abdiche f Soyalp r Moussa r riane K Hadji S Bin-Omran r Khenata Laboratoire synthese et Catalyse Ibn Khaldoun Universite of Tiaret Tiaret 14000 Algeria Laboratoire de Physique Quantique et de Modelisation Mathematique (LPQ3M) Departement de Technologie Universite de Mascara Mascara 29000 Algeria Department of Physics Faculty of Education Yuzuncu Ytl University 65080 Van Turkey Science and Technology D6partement Ibn Khaldoun Universite de Tiaret Tiaret 14000 Algeria Department of Physics and Astronomy College of Science King Sand University Riyadh 11451 Saudi Arabia

In this paper, we investigated the structural, electronic and optical properties of InAs, InN and InP binary compounds and their related ternary and quaternary alloys by using the full potential linearized augmented plane wave（fP-LAPW）method based on density functional theory（DfT）. The total energies, the lattice parameters, and the bulk modulus and its first pressure derivative were calculated using different exchange correlation approximations. The local density approach（LDA） and Tran–Blaha modified Becke–Johnson（TB-m BJ） approximations were used to calculate the band *** variations of the lattice parameters, the bulk modulus and the band gap with compositions x and y are ***, the optical properties and the dielectric function, refractive index and loss energy were computed. Our results are in good agreement with the validated experimental and theoretical data found in the literature.

关键词： density functional theory full potential linearized augmented plane wave Tran–Blaha modified Becke–Johnson approximations InAsxNyP1-x-y

Effect of Partial Substitution of Ni by Cu in LaNiO_3 Perovskite Catalyst for Dry Methane reforming

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催化学报 2012年第5期33卷 797-801页

作者： G.r.MOrADI f.KHOSrAVIAN M.rAHMANZADEH Catalyst research Center Chemical Engineering DepartmentFaculty of EngineeringRazi UniversityKermanshah 67149-67346Iran

A series of ternary perovskite type oxides LaNi1-xCuxO3(x = 0.2,0.4,0.6,0.8,and 1.0) were synthesized via the sol-gel method in propionic *** substitution of Ni by Cu showed higher activities and selectivities towards syngas ***0.8Cu0.2O3 was the most active toward the CH4 and CO2 conversions,and was selective for syngas ***-programmed reduction results showed that the addition of Cu facilitates the reduction of Ni3+ to Ni0,which is the main reason for the higher performance of this catalyst.

关键词： dry reforming of methane perovskite lanthanun nickel sol-gel method

Do vegetative and reproductive phenophases of deciduous tropical species respond similarly to rainfall pulses?

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Journal of forestry research 2013年第4期24卷 643-651页

作者： A.P.Silveira f.S.Araújo f.r.Martins Itapipoca faculty of Education Av.Monsenhor Tabosa s/ no.Ceará State University -- UECE Graduate Course of Ecology and Natural resources Department of BiologyBuilding 906Federal University of Ceará-UFC Department of Plant Biology Institute of BiologyP.O.Box 610University of Campinas – UNICAMP

Deciduous trees with high-density wood that occur in dry seasonal tropical regions respond to rainfall seasonality with synchrony in phenophases. However, they may exhibit interannual differences in synchrony and intensity of phenophases, as strategy for large variations in duration and intensity of rainfall pulses. Nevertheless, it remains unknown how phenophases of deciduous trees of the Brazilian semi-arid region respond to rainfall variations. The phenology of Cordia oncocalyx was monitored in deciduous thorny woodland （Caatinga）, from April 2009 to March 2011, and was correlated with rainfall, soil humidity, temperature, and photoperiod. The rainy years 2009 and 2011 exhibited higher duration of rainfall pulses and lower frequency of interpulses, but in 2010 pulse duration and total rainfall were lower. Circular statistics showed leaf flush followed by flowering and fruiting in the rainy season, and leaf fall and seed dispersal in the dry season.

关键词： asynchrony circular analysis deciduous phenology riskspreading seasonality.

Numerical Simulation of Bubble formation at a Single Orifice in Gas-fluidized Beds with Smoothed Particle Hydrodynamics and finite Volume Coupled Method

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Computer Modeling in Engineering & Sciences 2015年第1期104卷 41-68页

作者： f.Z.Chen H.f.Qiang W.r.Gao 601 Staff room Xi’an Hi–Tech InstituteXi’anShanxiPRCPC 710025

A coupled method describing gas–solid two-phase flow has been proposed to numerically study the bubble formation at a single orifice in gas-fluidized *** particles are traced with smoothed particle hydrodynamics,whereas gas phase is discretized by finite volume *** force,gas pressure gradient,and volume fraction are used to couple the two *** effect of injection velocities,particle sizes,and particle densities on bubble growth is analyzed using the coupled *** simulation results,obtained for two-dimensional geometries,include the shape and diameter size of a bubble as a function of time;such results are compared with experimental data,previous numerical results,and other approximate model predictions reported in the ***,the flow profiles of gas and particle phases and the temperature distribution by the heat transfer model around the forming bubble are also *** results show that the coupled method efficiently describes of the bubble formation in fluidized *** proposed method is applicable for solving gas–solid two-phase flow in fluidization.

关键词： coupled method smoothed particle hydrodynamics finite volumemethod bubble formation heat transfer fluidization

Psychiatric comorbidity in the treatment of patients with inflammatory bowel disease

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World Journal of Gastroenterology 2014年第13期20卷 3552-3563页

作者： Branislav r filipovic Branka f filipovic faculty of Medicine Institute of Anatomy "Niko Miljanic"11000 BelgradeSerbia Branislav R FilipovicBranka F FilipovicFaculty of MedicineUniversity of Belgrade11000 BelgradeSerbia Department of Gastroenterohepatology Clinical and Hospital Center "Bezanijska Kosa"11080 BelgradeSerbia

Ulcerative colitis and Crohn’s disease, commonly known as inflammatory bowel disease (IBD), draw attention from specialists of various disorders, including gastroenterology, psychiatry, and radiology. The involvement of a cortical influence in the brain-gut axis as well as the interaction of the hypothalamic-pituitary-adrenal axis and the peripheral nervous system provide an initial explanation of the psychological symptoms associated with IBD. The involvement of structures the limbic system, such as the anterior cingulate cortex, the prefrontal cortex, and the amygdala, paves the way for the discovery of the mechanisms underlying depression depression, anxiety, alexithymia, personality traits, and other psychological impairments following the onset of IBD. Psychiatric therapy in IBD patients is almost as important as the gastroenterological approach and consists of pharmacological treatment and psychotherapy. Neither of the available psychiatric treatment methods is considered the golden standard because both methods have side effects, and psychotropic medication can provoke the worsening of IBD symptoms. Thus, both approaches must be applied with awareness of the possibility of side effects. We suggest that psychiatrists and gastroenterologists work together to reach a consensus on IBD therapy to ensure success and to reduce side effects and relapse to the lowest possible rates.

关键词： Inflammatory bowel disease Psychiatry Treatment Personality traits Depression Anxiety

A non-relativistic model for the[cc]■ tetraquark

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Chinese Physics C 2019年第1期43卷 36-55页

作者： V.r.Debastiani f.S.Navarra Departamento de física Teórica and IfIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigación de Paterna Instituto de física Universidade de Sa?o Paulo Institut de Physique Théorique Université Paris SaclayCEA CNRS

We use a non-relativistic model to study the spectroscopy of a tetraquark composed of [cc]■ in a diquark-antidiquark *** numerically solving the Schr?dinger equation with a Cornell-inspired potential,we separate the four-body problem into three two-body ***-dependent terms(spin-spin,spin-orbit and tensor)are used to describe the splitting structure of the ■ spectrum and are also extended to the interaction between *** experimental data on charmonium states are used to fix the parameters of the model and a satisfactory description of the spectrum is *** find that the spin-dependent interaction is sizable in the diquark-antidiquark system,despite the heavy diquark mass,and also that the diquark has a finite size if treated in the same way as the ■ *** find that the lowest S-wave T 4c tetraquarks might be below their thresholds of spontaneous dissociation into low-lying charmonium pairs,while orbital and radial excitations would be mostly above the corresponding charmonium pair ***,we repeat the calculations without the confining part of the potential and obtain bound diquarks and bound *** might be relevant to the study of exotic charmonium in the quark-gluon *** T 4c states could be investigated in the forthcoming experiments at the LHC and BelleⅡ.

关键词： tetraquark charmonium diquark-antidiquark nonrelativistic spin

PArTIAL rEGULArITY fOr OPTIMAL DESIGN PrOBLEMS INVOLVING BOTH BULK AND SUrfACE ENErGIES

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Chinese Annals of Mathematics,Series B 1999年第2期20卷 137-158页

作者： f.H.LIN r.V.KOHN CourantInstituteofMathematicalSciences USA projectsupportedbytheNationalNaturalSciencefoundationofUSA

This paper studies a class of variational problems which involving both bulk and surfaceenergies. The bulk energy is of Dirichlet type though it can be in very general forms allowingunknowns to be scalar or *** surface energy is an arbitrary elliptic parametric integralwhich is defined on a free interface. One also allows other constraints such as volumes of partitioning sets. One establishes the existence and regularity theory, in particular, the regularityof the free interface of such problems.

关键词： Partial regularity Optimal design problem Nonlinear variational problems

Systematic radio Telescope Alignment Using Portable fringe Projection Profilometry

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Nanomanufacturing and Metrology 2024年第1期7卷 75-85页

作者： Joel Berkson Justin Hyatt Nathan Julicher Byeongjoon Jeong Isaac Pimienta rachel Ball Wyatt Ellis Jason Voris Diego Torres‑barajas Daewook Kim James C.Wyant College of Optical Sciences University of Arizona1630 E.University Blvd.TucsonAZ 85721USA Department of Astronomy at Steward Observatory University of Arizona933 N Cherry Ave.TucsonAZ 85721USA

In 2019,the Event Horizon Telescope(EHT)released the first-ever image of a black hole event *** are now aiming for higher angular resolutions of distant targets,like black holes,to understand more about the fundamental laws of gravity that govern our *** achieve this higher resolution and increased sensitivity,larger radio telescopes are needed to operate at higher frequencies and in larger *** like the next-generation Very Large Array(ngVLA)and the Square-Kilometer Array(SKA)require building hundreds of telescopes with diameters greater than 10 ms over the next *** has a twofold *** telescope surfaces need to be more accurate to operate at higher frequencies,and the logistics involved in maintaining a radio telescope need to be simplified to support them properly in large *** of these problems can be solved with improved methods for surface metrology that are faster and more accurate with a higher *** leads to faster and more accurate panel alignment and,therefore,a more productive *** this paper,we present the use of binocular fringe projection profilometry as a solution to this problem and demonstrate it by aligning two panels on a 3-m radio telescope *** measurement takes only 10 min and directly delivers feedback on the tip,tilt,and piston of each panel to create the ideal reflector shape.

关键词： Metrology fringe projection profilometry Off-axis alignment radio astronomy radio antenna

Steganography-Based Transmission of Medical Images Over Unsecure Network for Telemedicine Applications

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Computers, Materials & Continua 2021年第9期68卷 4069-4085页

作者： romany f.Mansour Moheb r.Girgis Department of Mathematics Faculty of ScienceNew Valley UniversityEl-Kharga72511Egypt Department of Computer Science Faculty of ScienceMinia UniversityEl-MiniaEgypt

Steganography is one of the best techniques to hide secret *** steganography methods are available that use an image as a cover object,which is called image *** image steganography,the major features are the cover object quality and hiding data *** to poor image quality,attackers could easily hack the secret ***,the hidden data quantity should be improved,while keeping stego-image quality *** main aim of this study is combining several steganography techniques,for secure transmission of data without leakage and unauthorized *** this paper,a technique,which combines various steganographybased techniques,is proposed for secure transmission of secret *** the pre-processing step,resizing of cover image is performed with Pixel repetition Method(PrM).Then DES(Data Encryption Standard)algorithm is used to encrypt secret data before embedding it into cover *** encrypted data is then converted to hexadecimal *** is followed by embedding using Least Signification Bit(LSB)in order to hide secret data inside the cover ***,image de-noising using Convolutional Neural Network(CNN)is used to enhance the cover image with hidden encrypted *** Zerotrees of Wavelet Transform is used to compress the image in order to reduce its *** are conducted to evaluate the performance of proposed combined steganography technique and results indicate that the proposed technique outperforms all existing *** achieves better PSNr,and encryption/decryption times,than existing methods for medical and other types of images.

关键词： Steganography secure data transmission CNN encryption telemedicine