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Performance Analysis of thermoacoustic Refrigerator of 10 W Cooling Power Made up of Poly-Vinyl-Chloride for Different Parallel Plate Stacks by Using helium as a Working Fluid

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Journal of thermal Science 2021年第6期30卷 2037-2055页

作者： n V Shivakumara BhEEMShA Arya Department of Mechanical Engineering BMS College of EngineeringBengaluru 560019India Department of Mechanical Engineering Government PolytechnicChannasandraBengaluru 560067India

Refrigerants are usually provided in the conventional refrigeration system although the refrigerants produce Chlorofluorocarbons(CFCs)and hydro-chlorofluorocarbons(hCFCs),which are hazardous to the ***,these disadvantages can be overcome by using air or inert gas in the thermoacoustic refrigeration *** the present experimental work,helium is used as a working gas with an operating pressure range of 0.2 MPa to 1.0 MPa in order to study the performance of thermoacoustic refrigerator(tAR)which is fabricated using Poly-Vinyl-Chloride(PVC).the parallel plate stacks with different porosity ratios have been considered to study the performance of *** temperature difference between the hot and cold heat exchanger and acoustic dynamic pressure were recorded by using Bruel and kjaer data acquisition system under different operating *** effect of different operating parameters such as operating frequency(200 hz to 600 hz),cooling load(2 W to 10 W)and drive ratio(0.6%to 1.6%)have also been considered to study the performance of *** tAR also modeled in DeltaEC software and the results are compared with the experimental outcomes and found to be in good *** experimental results show that-2.1℃is the lowest temperature measured at cold heat exchanger by achieving the highest temperature difference of about 32.9℃.An improvement is around 36%as compared to that of previous experiments that used aluminium *** highest Coefficient of Performance(COP)and the Relative Coefficient of Performance(COPR)are found to be 2.024 and 0.217,respectively.

关键词： thermoacoustic refrigerator parallel plate stack porosity ratio temperature difference COP COPR

Modified Classical Over Barrier Model for Multi-Charged Ion in Collisions with Multiple Electron target at Energies Below 1 keV/u

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Plasma Science and technology 2010年第3期12卷 369-371页

作者： k.IShII k.OkUnO Department of Physics Nara Women's University Kitauoyanishi

Charge transfer cross sections for kr^q＋ with ne are calculated quantitatively by using modified classical over barrier model in order to clarify energy dependence of charge transfer cross sections in low energy region. Essential of this model is taking the induced dipole potential into consideration. As a result, this calculation can reproduce systematic energy dependence of experimental results. this suggests that the bending trajectory of the projectile due to an induced dipole potential should be considered to describe pictures of collisions at low energy regime below 1 keV/u.

关键词： atomic processes highly charged ion charge transfer classical over barrier

Scientific guidelines for preclinical research on potentised preparations manufactured according to current pharmacopoeias-the PrePoP guidelines

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Journal of Integrative Medicine 2024年第5期22卷 533-544页

作者： Alexander L.tournier Leoni V.Bonamin Susann Buchheim-Schmidt Steven Cartwright Christoph Dombrowsky Paul Doesburg Carla holandino Maria Olga kokornaczyk Everine Bvan de kraats Jesús Antonio López-Carvallo Papiya nandy JoséManuel Mazón-Suástegui Fateme Mirzajani Bernard Poitevin Claudia Scherr karin thieves Sandra Würtenberger Stephan Baumgartner Institute of Complementary and Integrative Medicine University of Bern3010 BernBernSwitzerland Institute of Integrative Medicine Witten/Herdecke University58455 WittenNorth Rhine–WestphaliaGermany homeopathy Research Institute London SW74EFUnited Kingdom Graduate Program on Environmental and Experimental Pathology Paulista UniversitySão Paulo 01504-000São PauloBrazil Department of Medical Science Deutsche Homöopathie-Union DHU-Arzneimittel GmbH&Co.KG76227 KarlsruheBaden-WürttembergGermany Cherwell Laboratory for Fundamental Research in homeopathy Oxford OX28NUOxforeshireUnited Kingdom Society for Cancer Research Hiscia Research Institute4144 ArlesheimBaselSwitzerland Laboratório Multidisciplinar de Ciências Farmacêuticas Universidade Federal do Rio de JaneiroRio de Janeiro 21941-902Rio de JaneiroBrazil World Water Community Rotterdam 3029AKthe Netherlands Departamento de Acuicultura Facultad de Ciencias del MarUniversidad Católica del Norte1790437 CoquimboElquiChile Centre for Interdisciplinary Research and Education KolkataWest Bengal 700068West BengalIndia Laboratorio de homeopatía Acuícola y Semillas Marinas Centro de Investigaciones Biológicas del NoroesteLa Paz 23096Baja California SurMexico Protein Research Center Shahid Beheshti UniversityTehran ***Iran Department of Medical Laboratory Science College of ScienceKnowledge University44001 ErbilErbilIraq SociétéSavante d’homéopathie 75009 ParisFrance Sola Salus Institute for Homeopathic Research52511 GeilenkirchenNorth Rhine–WestphaliaGermany Scientific Society for homeopathy 06366 KöthenSaxony-AnhaltGermany

Objective Pharmacopoeias regulate the manufacture of potentised pharmaceutical preparations used in different branches of complementary and integrative *** physicochemical properties and biological activity of these preparations are often investigated in preclinical research,yet no guidelines for experimental research currently exist in this *** present PrePoP guidelines aim to provide recommendations to promote high-quality,statistically sound,and reproducible preclinical research on potentised *** Input was gathered from researchers nominated by the relevant scientific societies using a simplified Delphi consensus approach covering the most relevant aspects of basic research methodology in the field including appropriate controls,sample preparation and handling,and *** three rounds of feedback,a consensus was finally reached on the most important aspects and considerations for conducting high-quality research on potentised *** We present a series of recommendations on a range of topics including experimental controls,system stability,blinding and randomisation,environmental influences,and procedures for the preparation of potentised samples and controls,and we address some specific challenges of this research *** this expert consensus process resulted in a robust set of methodological guidelines for research on potentised preparations and provides a valuable framework that will inform and improve the quality of subsequent research in this emerging field.

关键词： Research guidelines Fundamental research Basic research Complementary and integrative medicine Potentisation Potentised preparations

Investigation of structural,magnetic and optical properties of rare earth substituted bismuth ferrite

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Journal of Rare Earths 2013年第4期31卷 370-375页

作者： t.Durga Rao t.karthik Saket Asthana Advanced Functional Materials Laboratory Department of PhysicsIndian Institute of Technology Hyderabad Department of Materials Science and Engineering Indian Institute of Technology Hyderabad

Polycrystalline BiFeO3 and rare earth substituted ***3 （BRFO, R=Y, ho and Er） compounds were prepared by rapid solid state sintering technique. Structural phase analysis indicated that all the compounds stabilized in rhombohedral structure （R3c space group） and a small orthorhombic phase fraction was observed in BRFO compounds. From the Raman spectra results, the changes in the phonon frequencies （A1） and line widths suggested lattice distortion in the BRFO compounds as was evidenced in the XRD analysis. Compared to the linear variation of magnetization with magnetic field （M-h） shown by BFO, an obvious M-h loop was observed in BRFO compounds which could be due to the suppression of space modulated spin structure and was explained on the basis of weak ferromagnetism and field induced spin reorientation. UV-Vis spectroscopy evidenced a change in local FeO6 envi- ronment due to shift in the 6Alg→4t2g energy transition band. BRFO compounds with improved remnant magnetization and coercive field are applicable for magnetoelectric devices.

关键词： structural distortion spin-reorientation G-type antiferromagnet rare earths

Chemical and pharmacological evaluation of hypericum perforation extracts

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Acta Pharmacologica Sinica 2000年第12期 90-97页

作者： B Duff SLOLEY,Liana J URIChUk,Ronald t COUttS,Peter k t PAnG,Jacqueline J ShAn CV technologies Edmonton Research Park 9411-20 Ave Edmonton Alberta Canada t6n 1E5 neurochemical Research Unit Department of Psychiatry University of Alberta Edmonton Alberta Canada t6G 2B7 Canada CV technologies Edmonton Research Park 9411-20 Ave Edmonton Alberta Canada t6n 1E5 neurochemical Research Unit Department of Psychiatry University of Alberta Edmonton Alberta Canada t6G 2B7 Canada CV technologies Edmonton Research Park 9411-20 Ave Edmonton Alberta Canada t6n 1E5 neurochemical Research Unit Department of Psychiatry University of Alberta Edmonton Alberta Canada t6G 2B7 Canada CV technologies Edmonton Research Park 9411-20 Ave Edmonton Alberta Canada t6n 1E5 neurochemical Research Unit Department of Psychiatry University of Alberta Edmonton Alberta Canada t6G 2B7 Canada CV technologies Edmonton Research Park 9411-20 Ave Edmonton Alberta Canada t6n 1E5 neurochemical Research Unit Department of Psychiatry University of Alberta Edmonton Alberta Canada t6G 2B7 Canada

kEY WORDS hypericum perforation; high pressure liquid chromatography; serotonin uptake inhibitors; tree radicals; antioxidants; hyperforin; hypericin; quercetin; rutinABStRACtAIM: to determine the concentrations of chemical characteristic to extracts of leaves and flowers of hypericum perforatnm (St John's wort) in a number of selected samples and, following chemical characterization, to investigate the effects of these extracts on several pharmacological properties including effects of the extracts on inhibition of 5-hydroxytryptamine (5-ht) uptake and on an-tioxidant properties. MEthODS: the samples were analyzed for the presence of characteristic chemicals by high performance liquid chromatography (hPLC) directly coupled to ultraviolet wavelength absorbance and positive or negative mode electrospray mass spectrometric detection. the effects of extracts on 5-ht uptake were determined by quantifying 3h-5-ht incorporation into rat hip-pocampal prisms. Estimates of effects of extracts on free radical sca

关键词： hypericum perforatum high pressure liquid chromatography serotonin uptake inhibitors free radicals antioxidants hyperforin hypericin quercetin rutin

Scalable arrays of chemical vapor sensors based on DnA-decorated graphene

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nano Research 2014年第1期7卷 95-103页

作者： nicholas J. kybert Gang hee han Mitchell B. Lerner Eric n. Dattoli Ali Esfandiar A. t. Charlie Johnson Department of Physics and Astronomy University of Pennsylvania Philadelphia PA 19104 USA SPAWAR Systems Center Pacific San Diego CA 92152 USA

Arrays of chemical vapor sensors based on graphene field effect transistors functionalized with single-stranded DnA have been demonstrated. Standard photolithographic processing was adapted for use on large-area graphene by including a metal protection layer, which protected the graphene from contamination and enabled fabrication of high quality field-effect transistors （GFEts）. Processed graphene devices had hole mobilities of 1,640 ± 250 cm2.V-1.s-1 and Dirac voltages of 15 ± 10 V under ambient conditions. Atomic force microscopy was used to verify that the graphene surface remained uncontaminated and therefore suitable for controlled chemical functionalization. Single-stranded DnA was chosen as the functionalization layer due to its affinity to a wide range of target molecules and π-π stacking interaction with graphene, which led to minimal degradation of device characteristics. the resulting sensor arrays showed analyte- and DnA sequence-dependent responses down to parts-per-billion concentrations. DnA/GFEt sensors were able to differentiate among chemically similar analytes, including a series of carboxylic acids, and structural isomers of carboxylic acids and pinene. Evidence for the important role of electrostatic chemical gating was provided by the observation of understandable differences in the sensor response to two compounds that differed only by the replacement of a （deprotonating） hydroxyl group by a neutral methyl group. Finally, target analytes were detected without loss of sensitivity in a large background of a chemically similar, volatile compound. these results motivate further development of the DnA/graphene sensor family for use in an electronic olfaction system.

关键词： graphene vapor sensor DnA photolithography chemical gating

Standardizing MI-tLIF, a Proposal for a Reproducible technique

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Open Journal of Modern neurosurgery 2024年第2期14卷 91-103页

作者： Iván Ulises Sámano López Jesús Alberto Pérez Contreras Emmanuel Cantú Chávez Diana Chávez Lizárraga Ana Sofía Peña Blesa thania karina Gutiérrez Anchondo Á ngeles Pedregal Ciudad de México México

Background: Minimally invasive transforaminal lumbar interbody fusion (MI tLIF) is a widely known and performed technique, however its versatility among different physicians continues to hinder its replication and results. therefore, this study aimed to provide a step-by-step surgical guide to perform a safe MI-tLIF, based on the results obtained in patients operated on by a single surgeon over a period of 12 years. Patients and methods: A retrospective, single center, longitudinal, and observational cohort study was conducted with 931 patients who underwent MI tLIF by a single surgeon between 2010 and 2022 using the technique described on this paper, each with a minimum follow-up of 12 months. Criteria included Schizas classification, listhesis according to Meyerding classification, number of levels treated, cage size, and complications (screw repositioning or cerebrospinal fluid leak). Patient clinical outcomes were assessed using the Oswestry Disability Index (ODI), Visual Analog Scale (VAS) for pre- and postoperative radicular pain. thin slice Ct scans were used to assess the progression of the fusion using the Bridwell classification. In the statistical analysis, percentages, median, and interquartile range (IQR) were calculated. Results: nine hundred and thirty one patients underwent MI tLIF using the technique described, eight hundred and eighty (94.5%) had a single level treated and fifty one (5.5%) had a 2 level procedure (982 levels), an 8mm cage was placed on five hundred and seventeenlevels (52.7%), six hundred and sixty three levels(67.6%) achieved grade I fusion, two hundred and sixty six levels (27.1%) achieved grade II fusion, 52 levels (5.3) achieved grade III fusion and one level (0.1) achieved a grade IV fusion or non-union. Revision surgery was performed on 3 patients (0.3%) for screw repositioning, cerebrospinal fluid leak was present on 2 patients during surgery and treated before closure. VAS scores and ODI were improved at 12 months postop (V

关键词： MItLIF Lumbar Interbody Fusion technique Pain Relief and Disability

DIMEnSIOnAL InStABILItY OF LD31 Al ALLOY WELDMEntS At ROOM tEMPERAtURE AnD AFtER thERMAL CYCLES

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Acta Metallurgica Sinica(English Letters) 2004年第1期17卷 64-70页

作者： X.S.Liu h.Y.Fang W.L.Xu X.t.tian X.D.Sun national key Laboratory of Advanced Welding Production and technology Harbin Institute of Technology Harbin 150001ChinaNational key Laboratory of Advanced Welding Production and Technology Harbin Institute of Technology Harbin 150001ChinaNational key Laboratory of Advanced Welding Production and Technology Harbin Institute of Technology Harbin 150001ChinaNational key Laboratory of Advanced Welding Production and Technology Harbin Institute of Technology Harbin 150001ChinaHarbin First Mechanical Production Factory Harbin 150080China

the unstable dimensional distortion of LD31 aluminum alloy weldments at room temperature and after thermal cycles was studied by use of light interference and CMM(three-coordinate measuring machines). At the same time, distortion mechanism was analyzed from the viewpoint of mechanics and micro structure. Experimental results show that there exists obvious difference of unstable dimensional distortion between LD31 welded specimens under two conditions mentioned above. Under room temperature, dimensional variation of welded specimens will decrease gradually and finally tends to be stable during 200h after welding. the relative elongation of welded specimen is 3.0×10-5; After thermal cycles, distortion of welded specimen is much larger than that at room temperature. After 11 thermal cycles, the dimension will tend to be stable. Dimensional unstable distortion of weldments mainly results from temperature condition, microstructure variation and relaxation of welding residual stress.

关键词： LD31 aluminum alloy light interference room temperature and thermal cycles dimensional instability

Feature identification in complex fluid flows by convolutional neural networks

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theoretical & Applied Mechanics Letters 2023年第6期13卷 447-454页

作者： Shizheng Wen Michael W.Lee kai M.kruger Bastos Ian k.Eldridge-Allegra Earl h.Dowell Department of Mathematics ETH ZurichZürich 8092Switzerland nASA Langley Research Center HamptonVA 23666USA Rivian San FranciscoCA 94080USA Department of Mechanical Engineering and Materials Science Duke UniversityDurhamNC 27708USA

Recent advancements have established machine learning's utility in predicting nonlinear fluid dynamics,with predictive accuracy being a central motivation for employing neural ***,the pattern recognition central to the networks function is equally valuable for enhancing our dynamical insight into the complex fluid *** this paper,a single-layer convolutional neural network(Cnn)was trained to recognize three qualitatively different subsonic buffet flows(periodic,quasi-periodic and chaotic)over a high-incidence airfoil,and a near-perfect accuracy was obtained with only a small training *** convolutional kernels and corresponding feature maps,developed by the model with no temporal information provided,identified large-scale coherent structures in agreement with those known to be associated with buffet *** to hyperparameters including network architecture and convolutional kernel size was also *** coherent structures identified by these models enhance our dynamical understanding of subsonic buffet over high-incidence airfoils over a wide range of Reynolds numbers.

关键词： Subsonic buffet flows Feature identification Convolutional neural network Long-short term memory