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Growth of Ni Films Observed by Scanning Tunneling Microscopy and X-ray

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Chinese Physics Letters 1999年第5期16卷 370-372页

作者： WANG De-liang u.Geyer National Laboratory for Superconductivity Institute of PhysicsChinese Academy of SciencesBeijing 100080 I.Physikalisches Institut der universitaet Goettingen Bunsenstrasse 9D-37073 GoettingenGermany

Scanning tunneling microscopy was used to measure the mean lateral dimensions D of grains at the surface of Ni films with thicknesses ranging from 15 to *** same films were analyzed by x-ray diffraction to obtain the average linear dimensionsδof coherent scattering regions in the direction normal to the film plane(coherence depths).For thin Ni films condensed on single sapphire substrate at room temperature,these two lengths D andδare equal and increase with film *** for films thicker than 130nm,these two lengths have different constant values and D>δ.This is because the coherent scattering depth is not only limited by the grain sizes but also by various defects in the *** difference between the constant values of D andδdisappears for films after annealing for 30min at 423K in the ultra-high vacuum system.

关键词： dimensions coherent film

Transcarotid transcatheter aortic valve implantation with a novel balloon expandable Myval^(■) ThV under the local anesthesia

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Journal of Geriatric Cardiology 2022年第7期19卷 562-564页

作者： hüseyin Ayhan Bilge Duran Karaduman Telat Keles Emrah uğuz Emre Boysan Engin Bozkurt Department of Cardiology Medicana International Ankara HospitalAtilim UniversityAnkaraTurkey Department of Cardiology Ankara City HospitalAnkara Yıldırım Beyazıt UniversityAnkaraTurkey Department of Cardiovascular Surgery Ankara City HospitalAnkara Yıldırım Beyazıt UniversityAnkaraTurkey Department of Cardiovascular Surgery Medicana International Ankara HospitalAnkaraTurkey Department of Cardiology Medicana International Ankara HospitalAnkaraTurkey

Since it was first acquainted to us in 2002,tr-anscatheter aortic valve implantation(TAVI)was rapidly applied and earned worldwide *** is the standard of care for patients with symptomatic severe aortic stenosis(AS),at in-termediate to high-risk and in some low-risk pa-tients in light of the recent data,principally if it can be performed transfemoral approach.

关键词： anesthesia aortic balloon

Correction of failure in antenna array using matrix pencil technique

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Chinese Physics B 2017年第6期26卷 491-498页

作者： S u Khan M K A Rahim Advanced RF & Microwave Research Group Department of Communication Engineering Faculty of Electrical Engineering Universiti Teknologi Malaysia 81310 Skudai Johor Malaysia

In this paper a non-iterative technique is developed for the correction of faulty antenna array based on matrix pencil technique（MPT）. The failure of a sensor in antenna array can damage the radiation power pattern in terms of sidelobes level and nulls. In the developed technique, the radiation pattern of the array is sampled to form discrete power pattern information set. Then this information set can be arranged in the form of hankel matrix（hM） and execute the singular value decomposition（SVD）. By removing nonprincipal values, we obtain an optimum lower rank estimation of hM. This lower rank matrix corresponds to the corrected pattern. Then the proposed technique is employed to recover the weight excitation and position allocations from the estimated matrix. Numerical simulations confirm the efficiency of the proposed technique, which is compared with the available techniques in terms of sidelobes level and nulls.

关键词： array correction low rank estimation matrix pencil technique singular value decomposition

Pulmonary Toxicity of a Formulated Preparation of Fenvalerate in Rats Subchronically Exposed by Nose Only Inhalation for 90 Days

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Biomedical and Environmental Sciences 2001年第4期14卷 333-340页

作者： u.MANI FAKRuLISLAM 等 InhalationToxicologyLaboratory IndustrialToxicologyResearchCentreM.G.MargP.Box.No.80M.G.MargLucknow－226001India DepartmentofMedicalElementolgoy＆Toxicology HamdardUniversityNewDelhi

Objective The pulmonary toxicity of a commercially available formulated preparation of Fenvalerate (Fen), a synthetic pyrethroid has been studied in rats following subchronic nose only inhalation exposure route. Method Adult male rats were exposed to Fen for 4h/day, 5 days a week for 90 days by using Flow Past Dynamic Nose only Inhalation Chamber. Results Fen exposed rats showed a significant increase in enzymatic activities of lactate dehydrogenase (LDh), acid phosphatase (ACP), alkaline phosphatase (ALP) and γ-glutamyl transferase (γ-GT) which are considered as biochemical indicators of pulmonary damage. The concomitant histopathological examination of Fen exposed rats' lung revealed inflammatory changes viz., influx of mononuclear cells admixed with a few giant cells in alveolar lumen, hypetrophied bronchiolar and alveolar epithelial lining cells and presence of edematous fluid in alveolar lumen alongwith congested parenchymatous blood vessels. Conclusion These results for the first time indicate the pulmonary toxic effects of a commonly used formulated Fen preparation by using rat model and nose only inhalation as the route of exposure.

关键词： Animals Behavior, Animal Body Weight Inhalation Exposure Insecticides Lung Male Nitriles Nose Organ Size Pyrethrins Rats Rats, Wistar

Study on Ship Automatic Berthing System with Mooring Lines

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China Ocean Engineering 2017年第1期31卷 19-29页

作者： K.u.Yang J.G.hur M.S.Choi D.J.Yeo J.h.Byun Department of Power System Engineering Chonnam National UniversityYeosu 550-749Korea College of Fisheries and Ocean Science Chonnam National UniversityYeosu 550-749Korea Departrnent of Maritime Police Science Chonnam National UniversityYeosu 550-749Korea

This study describes an automatic berthing system with mooring lines. It is designed to be berthed by using mooring device on the upper deck of a ship. It is to berth once maintaining parallel with the quay by controlling both forward and aft breast lines. Berthing method is used through length adjustment of mooring lines connected between ship and quay by controlling the angular velocity and the torque of hydraulic motor in mooring device. The study is conducted under three changing conditions of draft, such as even-keel, rise of the gravity center and trim to stern. Variables affecting berthing stability are determined based on the control performance of each condition. Bond graphs method is used to model the system. Controller is designed as PID control method of reference-model algorithm. The control program is composed of synchronous control system based on the equations derived with the numerical analysis. The tank test is conducted to verify the usefulness of the control program.

关键词： hydraulic maintain affecting berth torque adjustment draft attitude gravity verify

Factors that affect heart rate variability following acute resistance exercise:A systematic review and meta-analysis

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Journal of Sport and health Science 2022年第3期11卷 376-392页

作者： Sajith u.Marasingha-Arachchige JacoboÁ.Rubio-Arias Pedro E.Alcaraz Linda h.Chung uCAM Research Center for high Performance Sport Catholic University of MurciaMurcia 30107Spain LFE Research Group Department of Health and Human PerformanceFaculty of Physical Activity and Sport Science-INEFUniversidad Politécnica de MadridMadrid 28040Spain Faculty of Sport Catholic University of MurciaMurcia 30107Spain

Background:There is controversial evidence regarding the effect of acute resistance exercise(ARE) on heart rate variability(hRV) parameters,which indicates the activities of the cardiac autonomic nervous *** aim of this study was to perform a systematic review and meta-analysis of the literature on the effect of ARE on hRV parameters and identify its possible moderating ***:The PubMed-Medline,Web of Science,SPORTDiscus,and Cochrane Library databases were *** Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA) declaration was followed,and the methodological quality of the studies was *** level of significance was set at p≤***-six studies met the inclusion *** effect analyses between pre-and post-test interventions demonstrated an increase in normalized units low frequency(p uency/high frequency ratio(p he normal-to-normal(NN)interval(p uare of the successive differences(p units high frequency(p healthy individuals range:15 ± 1 to 48 ± 2 years;mean ± SD).Results:There were differences between the subgroups in the number of sets used in an exercise(p=0.05) for root mean square of the successive differences,as well as for exercise intensity(p=0.01) and rest between sets(p=0.05) for normalized units high ***,there were differences between the subgroups in training volume for root mean square of the successive differences(p=0.01),normalized units high frequency(p=0.003) and normalized units low frequency(p=0.02).Conclusion:Overall,there was a withdrawal of cardiac parasympathetic and activation of cardiac sympathetic modulations following ARE,and th

关键词： Cardiac Parasympathetic Sympathetic

Effects of Ta Addition on Microstructure and Transformation Behavior of Ni-Ti Alloys

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Journal of Materials Science & Technology 2001年第1期17卷 5-6页

作者： K.h.Wu and JL.Ma Department of Mechanical Engineering, Florida International university, Miami, FL 33174, u.S.A. Florida Int univ Dept Mech Engn Miami FL 33174 USA

The effect of adding Ta on the changes of microstructure and Ms temperature of a dualphase shape memory alloy with compositions of (Ni51 Ti49)1 -***. and Ni50-Ti50 -***.g were systematically studied. An optical microscope, SEM, X-ray diffraction and DSC were utilized in this work. The evolution of the microstructure as a function of Ta content was characterized. The variation of the Ni/Ti ratio in the NiTi phase plays an important role in the change of the Ms temperatures due to the addition of Ta. A pseudobinary NiTi-Ta phase diagram was proposed based on these results.

关键词： Ti Ta Effects of Ta Addition on Microstructure and Transformation Behavior of Ni-Ti Alloys

Buckling analysis of planar linear uniform deployable structures consisting of scissor-like element in space under compression

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Science China(Technological Sciences) 2021年第3期64卷 493-507页

作者： LI Bo WANG SanMin TAN u-Xuan School of Mechanical and Precision Instrument Engineering Xi’an University of TechnologyXi’an 710048China Department of Engineering Product Development Singapore University of Technology and DesignSingapore 487372Singapore School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China

This paper comprehensively investigates the buckling load and the stability of a planar linear array deployable structure composed of scissor-like element(SLE)under *** present,the researches on deployable structure are mainly focused on configuration design and dynamics characteristics of the mechanisms,but less on structural *** fact,when the external load exceeds the structural critical load value,the deployable structure will be permanently deformed or even collapse directly and no longer have any bearing *** address this issue,a new stability model is derived using linear elastic analysis method and substructure method to evaluate the buckling characteristics of the deployable structure with n SLEs when it is carried out in space,which can accurately obtain the structural instability load and can be used quantitatively to optimize the structure for making it have the most stable *** addition,the effects of the number of elements,the length,material properties and flexibility of the bar,and the deployment degree on the buckling of the scissor deployable structure are investigated,and the results of the theoretical analysis are compared with simulation and analytical results,respectively,confirming that the proposed stability model not only is able to effectively predict the structural instability load but also determine which part of the deployable structure is *** can be concluded that the stability of the deployable structure gradually decreases with the increase of the number of elements or the bar *** the calculation process,the critical load of each sub-element should be considered,and the minimum value of the critical loads of all subunits can be regarded as the instability load of the whole structure.

关键词： deployable structure stability analysis buckling load sub structure linear array simulation

Estimation of Rheological Properties of RAP Binder

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Journal of Wuhan university of Technology(Materials Science) 2010年第5期25卷 866-870页

作者：马涛 huSSAIN u Bahia School of Transportation Southeast University Nanjing 210096 China Department of Civil and Environmental Engineering University of Wisconsin-Madison 2205 Engineering Hall Madison WI 53706 USA

The low-temperature rheological properties of binders in the recycled asphalt pavement （RAP） material without the damaging effects of solvent extractions were analyzed. The developed procedure is based on testing of bitumen-RAP mortars produced by mixing the fresh （virgin） binder with RAP material smaller than # 8 sieve. Different mortars were prepared, containing RAP material passing the #8 sieve and 15% by weight of fresh binder. Low temperature properties of these mortars were investigated by using the bending beam rheometer （BBR） test procedure that is specially modified for testing of the RAP mortars. The modification involved the development of a new kind of mold and different testing parameters. The RAP material used in the experimental study were both extracted from real reclaimed pavement and prepared in the laboratory, by aging binder through repeated PAV cycles. The results indicate the new procedure can capture the effect of aged properties of bitumen in the RAP and can be used to estimate the PG low temperature grade of the blended binder. Although data is limited in size, the modification of the BBR appears to be simple and provide repeatable data.

关键词： RAP binder rheological properties aging bending beam rheometer