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chinese Physics B 2015年第12期24卷 334-341页

作者： m h moghtader Dindarlu m Kavosh Tehrani h saghafifar A maleki Institute of Optics and laser Malek-Ashtar University of Technology

In this paper, according to the temperature and strain distribution obtained by considering the Gaussian pump profile and dependence of physical properties on temperature, we derive an analytical model for refractive index variations of the diode side-pumped Nd：YAG laser rod. Then we evaluate this model by numerical solution and our maximum relative errors are 5% and 10% for variations caused by thermo–optical and thermo–mechanical effects; respectively. Finally, we present an analytical model for calculating the focal length of the thermal lens and spherical aberration. This model is evaluated by experimental results.

关键词： side-pumped laser rod Gaussian pump profile thermal effects thermal lens spherical aberration

control of tendon cell fate in the embryonic limb: A molecular perspective

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BIOcEll 2023年第3期47卷 465-471页

作者： JEssIcA cRIsTINA mARÍN-llERA cARlOs AmAURY JImÉNEZ-cÁRDENAs JEsÚs chImAl-mONROY Departamento de medicina Genómica y Toxicología Ambiental Instituto de Investigaciones BiomédicasUniversidad Nacional Autónoma de México Ciudad UniversitariaApartado Postal 70228MéxicoDF 04510México

The molecular cascade underlying tendon formation starts when progenitor cells begin to express the scleraxis(scx)*** knockout mice develop some but not all tendons,suggesting that additional factors are necessary for tendon commitment,maintenance,and *** transcription factors,such as mohawk(mkx)or early growth response(Egr),maintain scx expression and extracellular matrix formation during *** inhibition of wingless and int-related protein signaling is necessary and sufficient to induce the expression of *** the commitment of tenogenic lineage occurs,transforming growth factor-beta(TGFβ)induces the scx gene expression,becoming involved in the maintenance of tendon cell *** this point of view,we discussed two phases of the tenogenic process during limb development:dependent and independent of mechanical ***,we highlight the importance of understanding embryonic tendon development to improve therapeutic strategies in regenerative medicines for tendons.

关键词： Tendon differentiation Tenocyte scleraxis mohawk Early growth response Tendon development WNT TGFβ

Elastic, thermodynamic, electronic, and optical properties of recently discovered superconducting transition metal boride NbRuB:An ab-initio investigation

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chinese Physics B 2017年第10期26卷 339-347页

作者： F Parvin s h Naqib Department of Physics University of Rajshahi

The elastic, thermodynamic, electronic, and optical properties of recently discovered and potentially technologically important transition metal boride NbRuB, are investigated using the density functional formalism. Both generalized gradient approximation （GGA） and local density approximation （lDA） are used for optimizing the geometry and for estimating various elastic moduli and constants. The optical properties of NbRuB are studied for the first time with different photon polarizations. The frequency （energy） dependence of various optical constants complement quite well the essential features of the electronic band structure calculations. Debye temperature of NbRuB is estimated from the thermodynamical study. All these theoretical estimates are compared with published results, where available, and discussed in detail. Both electronic band structure and optical conductivity reveal robust metallic characteristics. The NbRuB possesses significant elastic anisotropy. Electronic features, on the other hand, are almost isotropic in nature. The effects of electronic band structure and Debye temperature on the emergence of superconductivity are also analyzed.

关键词： hard materials ternary borides DFT calculations electronic band structure optical properties superconductivity

microstructure evolution of a recycled Al-Fe-si-cu alloy processed by tube channel pressing

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International Journal of minerals,metallurgy and materials 2018年第10期25卷 1166-1172页

作者： m.h.Farshidi m.Rifai h.miyamoto Department of materials science and metallurgical Engineering Ferdowsi University of Mashhad Department of mechanical Engineering Doshisha University

Although excellent recyclability is one of the advantages of Al alloys, a recycling process can reduce different properties of these alloys by adding coarse AlFesi particles into the alloys' microstructures. One of the well-known methods for modifying the microstructure of metallic materials is the imposition of severe plastic deformation(sPD). Nevertheless, the microstructure evolutions of recycled Al alloys containing extraordinary fractions of AlFesi particles during sPD processing have seldom been considered. The aim of the present work is to study the microstructure evolution of a recycled Al–Fe–si–cu alloy during sPD processing. For this purpose, tubular specimens of the mentioned alloy were subjected to different numbers of passes of a recently developed sPD process called tube channel pressing(TcP); their microstructures were then studied using different techniques. The results show that coarse AlFesi particles are fragmented into finer particles after processing by TcP. however, decomposition and dissolution of AlFesi particles through TcP processing are negligible. In addition, TcP processing results in an increase in hardness of the alloy, which is attributed to the refinement of grains, to an increase of the dislocation density, and to the fragmentation of AlFesi particles.

关键词： AlFesi intermetallic particle severe plastic deformation microstructure tube channel pressing

A new nano-scale surface marking technique for the deformation analysis of mg-based alloys

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Journal of magnesium and Alloys 2022年第9期10卷 2398-2403页

作者： Y.h.huang s.W.Xu W.N.Tang J.F.Nie Department of materials science and Engineering Monash UniversityVictoria 3800Australia Automotive steel Research Institute Research Institute(R&D Centre)Baowu Iron&Steel Co.Ltd.Shanghai 201900China Received

In this work a new nanoscale surface marking technique,namely electron beam damage induced surface marking(EBDIsm),is developed and tested for the first time on a fine-grained pure mg *** technique utilizes focused high-energy electron beam of a scanning electron microscope to“burn”dense arrays of nano-scale grid patterns on the sample surface,and it is proved to be very effective for identifying and measuring localised deformation ***,the surface marking deposited by EBDIsm is not permanent and it tends to deteriorate ***,easy to use and versatile,the EBDIsm technique has a huge potential for quantitative measurement of strain field and nano-scale deformation analysis.

关键词： magnesium alloy Fine grain structure Deformation analysis surface patterning Deformation field

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

stress-Induced martensitic Transformation of Zr_(50)cu_(25)Ni_(10)co_(15) Nanocrystals Embedded in an Amorphous matrix

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Journal of materials science & Technology 2017年第3期33卷 276-280页

作者： W.h.Gao X.Y.Yi X.l.meng G.song W.cai l.c.Zhao school of materials science and Engineering Harbin Institute of Technology Department of mechanical Engineering University of Houston

The stress induced martensitic phase transformation of spherical Zrcu nanocrystals embedded in an amorphous matrix was studied in this paper. microstructural observations revealed that the martensitic transformation of the nanocrystal was hindered by the surrounding amorphous coating. The existence of two-step transformation from the austenite phase（B2） to the base structure martensite（B19＇） and finally to the most stable superstructure martensite（cm） was also demonstrated. The cm martensite with（021） type I twinning symmetrically accommodation was surrounded by the B19＇ martensite with dislocation morphologies.

关键词： Nanocrystals Zrcu martensitic phase transformation shape memory Transmission electron microscopy

Grid-connected microgrid:design and feasibility analysis for a local community in Bangladesh

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clean Energy 2022年第3期6卷 447-459页

作者： Dewan mahnaaz mahmud s.m.masum Ahmed sayeed hasan mohammad Zeyad Energy and Technology Research Division Advanced BioinformaticsComputational Biology and Data Science LaboratoryBangladesh Faculty of Engineering Erasmus Mundus Joint MSc in Smart Cities and Communities(SMACCs)University of Mons(UMONS)Belgium school of Engineering and Physical sciences(EPs) Erasmus Mundus Joint MSc in Smart Cities and Communities(SMACCs)Heriot-Watt University(HWU)UK

Global demand for electricity is growing significantly in developing *** energy accounts for barely 3%of total energy consumption in *** of renewable energy,***,are increasingly being acknowledged as viable supply-side choices for *** article presents a grid-connected microgrid design based on meteorological data for a local community situated in mohammadpur,*** study presents a feasible design of a system that gives the lowest cost of energy production and emissions that is evaluated using software named hybrid Optimization multiple Energy Resources(hOmER Pro).comparison and assessment of the net present cost,cost of energy,operating cost and environmental emission for five different feasible microgrids are analysed concerning real-time ***,a suitable case is sorted out and proposed for the local community for *** proposed case offers a$0.0442/kWh cost of energy,which is~32%cheaper than the current rate with a 57.5%renewable fraction and a payback period of 16.86 *** of this local community will have access to considerably more clean energy at a lower price by this study;also this design could sell the excess energy to the grid to avoid frequent electricity outages.

关键词： renewable energy communities microgrid community energy photovoltaic batteries emission cost of energy

homotopy analysis solutions for the asymmetric laminar flow in a porous channel with expanding or contracting walls

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Acta mechanica sinica 2011年第2期27卷 208-214页

作者： X.-h. si l.-c. Zheng X.-X. Zhang Y. chao Applied science school University of Science and Technology Beijing 100083 Beijing China Department of mechanical Engineering University of Science and Technology Beijing100083 Beijing China Research Institute of chemical Defense of the El.A 102205 Beijing China

In this paper, the asymmetric laminar flow in a porous channel with expanding or contracting walls is investigated. The governing equations are reduced to ordinary ones by using suitable similar transformations. homotopy analysis method （hAm） is employed to obtain the expres- sions for velocity fields. Graphs are sketched for values of parameters and associated dynamic characteristics, especially the expansion ratio, are analyzed in detail.

关键词： homotopy analysis method · Expanding or contracting wall · Asymmetric laminar flow · Porous channel · Expansion ratio

A Novel Technique for Detecting Various Thyroid Diseases Using Deep learning

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Intelligent Automation & soft computing 2023年第1期35卷 199-214页

作者： soma Prathibha Deepak Dahiya c.R.Rene Robin cherukuru Venkata Nishkala s.swedha Department of Information Technology Sri Sai Ram Engineering CollegeChennai600044India college of computer and Information sciences(ccIs) Majmaah UniversityMajmaah11952Kingdom of Saudi Arabia Department of computer science and Engineering Sri Sai Ram Engineering CollegeChennai602109India Associate solutions Engineer PegasystemsChennai600044India systems Engineer Infosys Ltd.Chennai600119India

Thyroid disease is a medical condition caused due to the excess release of thyroid *** is released by the thyroid gland which is in front of the neck just below the *** pictures such as X-rays and cT scans can,however,be used to diagnose *** this proposed model,Deep learning technology is used to detect thyroid diseases.A convolution Neural Network(cNN)based modified ResNet architecture is employed to detectfive different types of thyroid diseases namely *** *** *** cancer *** *** *** the proposed work,the training method is enhanced using dual optimizers for better accuracy and ***,a Python library that is high level runs as the main part of the Tensor Flow *** is used in the proposed work to implement deep learning *** comparative analysis of the proposed model and the existing work helps to show that there is a great improvement in the performance metrics in classifying the type of thyroid *** applying Adam and sGD(stochastic Gradient Descent)optimizers in the training phase of the proposed model it was identified that these increase the operational efficiency of the modified ResNet *** retraining the model with sGD,the modified ResNet provides more accuracy of about 97%whereas the basic ResNet architecture attains 94%accuracy.A web-based frame-work is also developed which yields the type of thyroid disease as the output for a given input scanned image of the system.

关键词： Thyroid deep learning convolution neural network modified ResNet dual optimizer