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mechanical and thermodynamical stability of BiVO4 polymorphs using first-principles study

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Chinese Physics B 2017年第3期26卷 395-403页

作者： A K m Farid UI Islam md Nurul Huda Liton H m Tariqul Islam md Al Helal md Kamruzzaman Department of Computer Science and Engineering Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Physics Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Chemistry Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Physics and materials Science and Center of Super-Diamond and Advanced Films (COSDAF) City University of Hong Kong Hong Kong SAR China

First principles calculations of structural, electronic, mechanical, and thermodynamic properties of different poly- morphs of BiVO4 are performed using Bender-type plane/wave ultrasoft pseudopotentials within the generalized gradient approximation （GGA） in the flame of density functional theory （DFT）. The calculated structural and electronic properties are consistent with the previous theoretical and experimental results. The electronic structures reveal that m-BiVO4, op- BiVO4, and st-BiVO4 have indirect band gaps, on the other hand, zt-BiVO4 has a direct band gap. From the DOS and mulliken＇s charge analysis, it is observed that only m-BiVO4 has 6s2 Bi lone pair. Bond population analysis indicates that st-BiVO4 shows a more ionic nature and a similar result is obtained from the elastic properties. From the elastic prop- erties, it is observed that st-BiVO4 is more mechanically stable than the others, st-BiVO4 is more ductile and useful for high electro-optical and electro-mechanical coupling devices. Our calculated thermodynamic properties confirm the similar characteristics found from electronic and elastic properties, m-BiVO4 is useful as photocatalysts, solid state electrolyte, and electrode and other polymorphs are applicable in electronic device fabrications.

关键词： BiVO4 crystal structure lone pair mechanical stability

Non-axisymmetric Homann mHD stagnation point flow of Al2O3-Cu/water hybrid nanofluid with shape factor impact

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Applied mathematics and mechanics(English Edition) 2020年第8期41卷 1125-1138页

作者： m.KHAN J.AHmED F.SULTANA m.SARFRAZ Department of mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

The heat transfer of Homann flow in the stagnation region of the Al2 O3-Cu/water hybrid nanofluid is investigated by adopting the Tiwari-Das model over a cylindrical *** effects of the nanoparticle shape,the viscous dissipation,and the nonlinear radiation are *** governing equations are obtained by using similarity transformations,and the numerical outcomes for the flow and the temperature field are noted by bvp4 c on *** numerical solutions of the flow field are compared with the asymptotic behaviors of large shear-to-strain-rate *** effects of variations of parameters involved are inspected for both nanofluid and hybrid nanofluid flows,temperature profiles,local Nusselt numbers,and skin *** is concluded that the velocity and temperature fields in the hybrid nanophase function more rapidly than those in the nanofluid phase.

关键词： cylindrical disk hybrid nanofluid magnetic field non-linear thermal radiation stagnation point flow viscous dissipation

In silico Analysis of osr40c1 Promoter Sequence Isolated from Indica Variety Pokkali

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Rice science 2017年第4期24卷 228-234页

作者： W.S.I.deSILVA m.m.N.PERERA K.L.N.S.PERERA A.m.WICKRAmASURIYA G.A.U.JAYASEKERA Department of Plant Sciences Faculty of ScienceUniversity of ColomboColombo 00300Sri Lanka Genetech molecular Diagnostics and School of Gene Technology Colombo 00800Sri Lanka

The promoter region of a drought and abscisic acid （ABA） inducible gene, osr40c1, was isolated from a salt-tolerant indica rice variety Pokkali, which is 670 bp upstream of the putative translation start codon. In silico promoter analysis of resulted sequence showed that at least 15 types of putative motifs were distributed within the sequence, including two types of common promoter elements, TATA and CAAT boxes. Additionally, several putative cis-acing regulatory elements which may be involved in regulation of osr40c1 expression under different conditions were found in the 5′-upstream region of osr40c1. These are ABA-responsive element, light-responsive elements （ATCT-motif, Box I, G-box, GT1-motif, Gap-box and Sp1）, myeloblastosis oncogene response element （CCAAT-box）, auxin responsive element （TGA-element）, gibberellin-responsive element （GARE-motif） and fungal-elicitor responsive elements （Box E and Box-W1）. A putative regulatory element, required for endosperm-specific pattern of gene expression designated as Skn-1 motif, was also detected in the Pokkali osr40c1 promoter region. In conclusion, the bioinformatic analysis of osr40c1 promoter region isolated from indica rice variety Pokkali led to the identification of several important stress-responsive cis-acting regulatory elements, and therefore, the isolated promoter sequence could be employed in rice genetic transformation to mediate expression of abiotic stress induced genes.

关键词： osr40c1 promoter cis-acting regulatory element rice

基于深度强化学习的空天地一体化网络信息物理系统垂直切换策略

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通信学报 2024年第8期45卷 180-191页

作者：武艳潘广川姚明旿杨清海梁中明西安电子科技大学空天地一体化综合业务网全国重点实验室陕西西安710071 深圳大学计算机与软件学院物联网研究中心广东深圳518060

针对空天地一体化网络信息物理系统模型复杂、很难获得网络拓扑先验知识和模型化假设的特点,研究其基于深度强化学习的垂直切换策略。首先,综合考虑系统稳定性、切换开销和网络使用成本约束,将垂直切换策略问题建模为约束马尔可夫决策过... 详细信息

针对空天地一体化网络信息物理系统模型复杂、很难获得网络拓扑先验知识和模型化假设的特点,研究其基于深度强化学习的垂直切换策略。首先,综合考虑系统稳定性、切换开销和网络使用成本约束,将垂直切换策略问题建模为约束马尔可夫决策过程(CmDP),并给出保证可行解存在的充分条件;其次,提出约束-近端策略优化(CPPO)算法解决该问题,并在基站侧引入分布式强化学习机制加速训练收敛。相较于基准策略,仿真验证了所提垂直切换策略的优越性和有效性。

关键词：空天地一体化网络信息物理系统深度强化学习垂直切换

In vitro Ruminal Gas Production Kinetics of Four Fodder Trees Ensiled With or Without molasses and Urea

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Journal of Integrative Agriculture 2013年第7期12卷 1234-1242页

作者： Abdelfattah Z m Salem ZHOU Chuan-she TAN Zhi-liang miguel mellado moises Cipriano Salazar mona m m Y Elghandopur Nicholas E Odongo Faculty of Veterinary and Livestock Autonomous University of the State of Mexico Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical Agriculture Chinese Academy of Sciences Department of Animal Nutrition Autonomous Agrarian University Antonio Narro Faculty of Veterinary and Livestock Autonomous University of Guerrero

This study investigated if the addition of urea （U）, molasses （m） or their 1：1 （v/v） mixture during ensiling increases the nutritional value of forage from four fodder trees （Prunus persica, Leucaena esculenta, Acacia farnesiana, and Prunus domestica）. Forage samples of fodder trees were collected in triplicate （three individual samples of each species） and subjected to an in vitro gas production （GP） procedure. Fermentation at 24 h （GP 24）, short-chain volatile fatty acids （SCFA）, and microbial crude protein production （mCP）, in vitro organic matter digestibility （OmD）, metabolizable energy （mE） and dry matter degradability （DmD） were estimated. Forage samples were incubated for 72 h in an incubator at 39oC and the volume of GP was recorded at 2, 4, 6, 8, 10, 12, 24, 48, and 72 h of incubation using the reading pressure technique. The rumen fermentation profiles were highest for P. persica, which showed the highest （P〈0.0001） DmD, mE, OmD, SCFA, GP 24 and mCP. On the other hand L. esculenta had the lowest （P〈0.0001） DmD, SCFA, mCP; P. domestica had the lowest （P〈0.0001） OmD. The addition of m to silage increased （P〈0.0001） mE and OmD, as well as GP. However, the addition of U and the mixture of U and m reduced （P〈0.0001） DmD, mE, OmD, SCFA, GY 24 and mCP. These results show that P. persica has the highest nutritive value and L. esculenta the lowest for ruminants. Additionally, the addition of m to forage from fodder trees increases rumen GP and fermentation, which may improve nutrient utilization in ruminants.

关键词： fodder trees urea molasses gas production

Analysis of antisym metric cross-ply laminates using high-order shear deformation theories:a meshless approach

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Acta mechanica Sinica 2020年第5期36卷 1078-1098,I0003页

作者： D.E.S.Rodrigues J.Belinha L.m.J.S.Dinis R.m.Natal Jorge Institute of Science and Innovation in mechanical and Industrial Engineering 4200-465 PortoPortugal Department of mechanical Engineering School of EngineeringPolytechnic of Porto(ISEP)4200-072 PortoPortugal Department of mechanical Engineering Faculty of EngineeringUniversity of Porto(FEUP)4200-465 PortoPortugal

For many years finite element method(FEm)was the chosen numerical method for the analysis of composite ***,in the last 20 years,the scientific community has witnessed the birth and development of several meshless methods,which are more flexible and equally accurate numerical *** meshless method used in this work is the natural neighbour radial point interpolation method(NNRPIm).In order to discretize the problem domain,the NNRPIm only requires an unstructured nodal ***,using the Voronoi mathematical concept,it enforces the nodal connectivity and constructs the background integration *** NNRPIm shape functions are constructed using the radial point interpolation *** this work,the displacement field of composite laminated plates is defined by high-order shear deformation *** the end,several antisymmetric cross-ply laminates were analysed and the NNRPIm solutions were compared with the *** obtained results show the efficiency and accuracy of the NNRPIm formulation.

关键词： Antisymmetric cross-ply laminates High-order shear deformation theories meshless methods Naturalneighbour radial point interpolation method(NNRPIm)

Luminescent properties of praseodymium doped Y_2O_3 and LaAlO_3 nanocrystallites and polymer composites

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Journal of Rare Earths 2011年第12期29卷 1123-1129页

作者： m.Dudek A.Jusza K.Anders L.Lipińska m.Baran R.Piramidowicz Faculty of Physics Warsaw University of Technology Institute of microelectronics and Optoelectronics Warsaw University of Technology Institute of Electronic materials Technology

Luminescent properties of Y2O3 and LaAlO3 nanopowders doped with Pr^3＋ ions and PmmA-based composite materials doped with these powders were reported. The set of active nanopowders differing in praseodymium ions concentration was prepared using sol-gel method and carefully characterized with respect to emission properties in the visible spectral range. In particular, the excitation and emission spectra were measured together with fluorescence decay profiles and the differences between optical properties of these materials were discussed and compared with data available for bulk materials. Finally, the PmmA-based composite materials doped with Pr^3＋：Y2O3 and Pr^3＋：LaAlO3 nanopowders were manufactured and characterized. The obtained results showed that polymer composites doped with active nanopowders in general tended to keep the luminescent properties of the original nanopowders.

关键词： nanocrystals praseodymium Y2O3 LaAlO3 visible emission PmmA nanocomposites rare earths

Experimental studies and artificial neural network modeling of surface tension of aqueous sodium L-prolinate solutions and piperazine blends

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Chinese Journal of Chemical Engineering 2019年第8期27卷 1904-1911页

作者： muhammad Shuaib Shaikh A.m.Shariff m.A.Bustam Sahil Garg Khadija Qureshi Pervez Hameed Shaikh Inamullah Bhatti Department of Chemical Engineering Mehran University of Engineering&Technology JamshoroSindh 76062Pakistan CO2 Research Centre(CO2RES) Universiti Teknologi PETRONASBandar Seri Iskandar 32610PerakMalaysia School of Chemical Engineering The University of QueenslandSt Lucia 4072Australia Office of Research Innovation and Commercialization(ORIC) Mehran University of Engineering&Technology JamshoroSindh 76062Pakistan

The surface tension study is very crucial for the design of CO2 gas absorption contacting equipment. The significance of the surface tension has been increasing due to its consideration in various technological fields. This property influences the mass transfer and hydrodynamics of gas absorption systems, mainly multiphase systems, in which the interface between gas and liquid exists. Therefore, in this study, surface tension of aqueous solutions of sodium L-prolinate(SP) and piperazine(PZ) blends were measured at ten different temperatures from(298.15 to 343.15) K. The SP mass fractions were 0.10, 0.20, and 0.30;while the mass fractions of PZ were 0.02 and 0.05. The experimental results showed that the surface tension increase with increasing the mass fractions of SP and PZ in aqueous blends, and decrease linearly with rising temperature. The experimental data of surface tension were correlated by two empirical correlations as a function of temperature and mass fractions for estimating the predicted data using the optimized correlation coefficients. moreover, the modeling of surface tension data was carried out using Artificial Neural Network(ANN) approach. The results obtianed from ANN modeling were compared with applied empirical correlation. It was found that the ANN approach outperformed the empirical correlation used in this study. Besides, a quantitative analysis of variation(ANOVA) was performed in order to determine the significance of data. The surface tension of aqueous SP and SP + PZ was also compared with various conventional solvents.

关键词： Surface tension L-Prolinate Piperazine Correlation Prediction Neural network

Influence of morse Potential on DNA Dynamics

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Chinese Physics Letters 2006年第1期23卷 65-68页

作者： ZDRAVKOVIC S SATARIC m. V. Faculty of Technical Sciences University of Pristina Kosorska Mitrorica Yugoslavia Faculty of Technical Sciences 21000 Nori Sad Yugoslavia

Based on the Peyrard-Bishop-Dauxois （i.e. the extended Peyrard-Bishop） model of DNA dynamics, the transversal hydrogen interaction is modelled by morse potential and the impact of the morse parameters on the DNA dynamics is investigated. In particular, we show how modulation of the signal, moving through the DNA chain, depends on those parameters. It is also shown that the DNA dynamics represents the interplay between dispersion and nonlinearity. Finally, we discuss the values of coupling constants κ and K.

关键词： NONLINEAR HELICOIDAL mODEL VISCOSITY BREATHER ImPACT