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Modeling of fluid-induced vibrations and identification of hydrodynamic forces on flow control valves

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Journal of Central South University 2015年第7期22卷 2596-2603页

作者： Samad Mehrzad ilgar Javanshir Ahmad Rahbar Ranji Seyyed Hadi Taheri Department of Maritime Engineering Science and Research Branch Islamic Azad University Young Researchers and Elite Club Tabriz Branch Islamic Azad University Department of Maritime Engineering Amirkabir University

Dynamics and vibration of control valves under flow-induced vibration are analyzed. Hydrodynamic load characteristics and structural response under flow-induced vibration are mainly influenced by inertia, damping, elastic, geometric characteristics and hydraulic parameters. The purpose of this work is to investigate the dynamic behavior of control valves in the response to self-excited fluid flow. An analytical and numerical method is developed to simulate the dynamic and vibrational behavior of sliding dam valves, in response to flow excitation. In order to demonstrate the effectiveness of proposed model, the simulation results are validated with experimental ones. Finally, to achieve the optimal valve geometry, numerical results for various shapes of valves are compared. Rounded valve with the least amount of flow turbulence obtains lower fluctuations and vibration amplitude compared with the flat and steep valves. Simulation results demonstrate that with the optimal design requirements of valves, vibration amplitude can be reduced by an average to 30%.

关键词： flow-induced force hydrodynamic force finite element method(FEM) valve design fluid-structure interaction vibration

Optimization of suspension system of heavy off-road vehicle for stability enhancement using integrated anti-roll bar and coiling spring mechanism

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Journal of Central South University 2018年第9期25卷 2289-2298页

作者： ilgar JAVANSHIR Andino MASELENO Shahin TASOUJIAN Majid OVEISI Young Researches and Elite Club Tabriz BranchIslamic Azad UniversityTabrizIran Department of Information Systems STMIK PringsewuLampungIndonesia Department of Mechanical Engineering University of TabrizTabriz 51638-43561Iran Faculty of Marine Engineering Chabahar Maritime UniversityChabahar 99717-56499Iran

Short suspension system has an indispensable effect on vehicle handling and ride,so,optimization of vehicle suspension system is one of the most effective methods,which could considerably enhance the vehicle stability and *** control,stability maintenance and ride comfort improvement are fundamental issues in design of suspension system of off-road *** this work,a dependent suspension system mostly used in off-road vehicles is modeled using Trucksim ***,geometric parameters of suspension system are optimized using integrated anti-roll bar and coiling spring in a way that ride comfort,handling and stability of vehicle are *** simulation results of suspension system and variations of geometric parameters due to road roughness and different steering angles are presented in Trucksim and effects of optimization of suspension system during various driving maneuvers in both optimized and un-optimized conditions are *** simulation results indicate that the type of suspension system and geometric parameters have significant effect on vehicle performance.

关键词： off-road vehicles handling anti-roll bar coil spring vehicle lateral dynamic Trucksim software

The in-vivo assessment of Turkish propolis and its nano form on testicular damage induced by cisplatin

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Journal of Integrative Medicine 2021年第5期19卷 451-459页

作者： Pinar Tatli Seven Ismail Seven Selcan Karakus Seda Iflazoglu Mutlu Seyma Ozer Kaya Gozde Arkali Merve ilgar Ezgi Tan Yesim Muge Sahin Deniz Ismik Ayben Kilislioglu Department of Animal Nutrition and Nutritional Diseases Faculty of Veterinary MedicineFirat UniversityElazig23119Turkey Department of Plant and Animal Production Vocation School of SivriceFtrat UniversityElazig 23119Turkey Department of Chemistry Faculty of EngineeringIstanbul University-CerrahpasaIstanbul 34320Turkey Department of Reproduction and Artificial Insemination Faculty of Veterinary MedicineFirat UniversityElazig 231J9Turkey Department of Physiology Faculty of Veterinary MedicineFirat UniversityElazig 23119Turkey Istanbul Arel University ArelPOTKAM(Polymer Technologies and Composite Application and Research Center)Istanbul 34537Turkey Department of Biomedical Engineering Faculty of Engineering and ArchitectureIstanbul Arel UniversityIstanbul 34537Turkey Department of Electrical Electronics Engineering Faculty of Engineering and Natural SciencesKadir Has UniversityIstanbul 34083Turkey

Objective: Chemotherapeutic drugs, such as cisplatin(CP), which are associated with oxidative stress and apoptosis, may adversely affect the reproductive system. This study tests whether administration of propolis and nano-propolis(NP) can alleviate oxidative stress and apoptosis in rats with testicular damage induced by ***: In this study, polymeric nanoparticles including propolis were synthesized with a green sonication method and characterized using Fourier transform-infrared spectroscopy, Brunauer-EmmettTeller, and wet scanning transmission electron microscopy techniques. In total, 56 rats were divided into the following seven groups: control, CP, propolis, NP-10, CP + propolis, CP + NP-10, and CP + ***(100 mg/kg), NP-10(10 mg/kg), and NP-30(30 mg/kg) treatments were administered by gavage daily for 21 d, and CP(3 mg/kg) was administered intraperitoneally in a single dose. After the experiment,oxidative stress parameters, namely, malondialdehyde(MDA), glutathione(GSH), glutathione peroxidase(GPx), and catalase(CAT), and apoptotic pathways including B cell leukemia/lymphoma-2 protein(Bcl-2)and Bcl-2-associated X protein(Bax) were measured in testicular tissues. Furthermore, sperm quality and weights of the testis, epididymis, right cauda epididymis, seminal vesicles and prostate were ***: Propolis and NP(especially NP-30) were able to preserve oxidative balance(decreased MDA levels and increased GSH, CAT, and GPx activities) and activate apoptotic pathways(decreased Bax and increased Bcl-2) in the testes of CP-treated rats. Sperm motility in the control, CP, and CP + NP-30 groups were 60%, 48.75%, and 78%, respectively(P<0.001). Especially, NP-30 application completely corrected the deterioration in sperm features induced by ***: The results show that propolis and NP treatments mitigated the side effects of CP on spermatogenic activity, antioxidant situation, and apoptosis in rats.

关键词： Cisplatin Nano-propolis Reproductive system Testicular damage

Features of the Conductivity of the Ag₈Ge_1-xMn_xTe₆ Solid Solutions

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Journal of Materials Science and Chemical Engineering 2022年第5期10卷 16-28页

作者： Rashad Rahimov Aynur Gahramanova Durdana Arasly Almaz Halilova ilgar Mammadov Institute of Physics of Azerbaijan National Academy of Sciences Baku Azerbaijan

Samples of Ag8Ge1-xMnxTe6 solid solutions with different manganese content (x = 0, 0.05, 0.1, 0.2) were prepared by fusing and further pressing their powders under the pressure of 0.6 GPa. In addition of Mn atoms to the Ag8GeTe6 compound leads to compression of their lattice. All p-type samples acquire a high resistance below the transition at temperatures of 180 - 220 K. The electrical conductivity of all compositions in the range of 220 - 300 K increases due to hopping mechanism, and at temperatures T > 320 K, a semiconductor characteristic is observed. By studying impedance spectra of samples, it was established that at 80 K solid solutions behave like a homogeneous dielectric material. At high temperatures and frequencies of an external electric field, a significant role of grain boundaries in conductivity was revealed. The dielectric anomaly occurring at low frequencies is also associated with an effect that manifests itself in the grain boundary.

关键词： Solid Solutions X-Ray Diffraction Hopping Conductivity Electrical Conductivity Impedance Spectra

Contribution of functional KIR3DL1 to ankylosing spondylitis

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Cellular & Molecular Immunology 2010年第6期7卷 471-476页

作者： Ivan V Zvyagin ilgar Z Mamedov Olga V Britanova Dmitriy B Staroverov Evgeni L Nasonov Anna G Bochkova Anna V Chkalina Alexei A Kotlobay Dmitriy O Korostin Denis V Rebrikov Sergey Lukyanov Yuri B Lebedev Dmitriy M Chudakov Shemiakin-Ovchinnikov Institute of Bioorganic Chemistry RASMoscowRussia Institute of Rheumatology RAMSMoscowRussia DNA-Technology JSC MoscowRussia Vavilov Institute of General Genetics MoscowRussia

Increasing evidence points to a role for killer immunoglobulin-like receptors(KIRs)in the development of autoimmune *** particular,a positive association of KIR3DS1(activating receptor)and a negative association of KIR3DL1(inhibitory receptor)alleles with ankylosing spondylitis(AS)have been reported by several ***,none of the studies analyzed these associations in the context of functionality of polymorphic *** better understand how the KIR3DL1/3DS1 genes determine susceptibility to AS,we analyzed the frequencies of alleles and genotypes encoding functional(KIR3DL1*F)and non-functional(KIR3DL1*004)*** genotyped 83 AS patients and 107 human leukocyte antigen(HLA)-B27-positive healthy controls from the Russian Caucasian population using a two-stage sequence-specific primer PCR,which distinguishes KIR3DS1,KIR3DL1*F and KIR3DL1*004 *** the patients carrying two functional KIR3DL1 alleles,those alleles were additionally genotyped to identify KIR3DL1*005 and KIR3DL1*007 alleles,which are functional but are expressed at low ***3DL1 was negatively associated with AS at the expense of KIR3DL1*F but not of KIR3DL1**** finding indicates that the inhibitory KIR3DL1 receptor protects against the development of AS and is not simply a passive counterpart of the segregating KIR3DS1 allele encoding the activating ***,analysis of genotype frequencies indicates that the presence of KIR3DS1 is a more important factor for AS susceptibility than the absence of KIR3DL1**** activation of either natural killer(NK)or T cells via the KIR3DS1 receptor can be one of the critical events in AS development,while the presence of the functional KIR3DL1 receptor has a protective ***,even individuals with a genotype that carried two inhibitory KIR3DL1 alleles expressed at high levels could develop AS.

关键词： ankylosing spondylitis autoimmune disease HLA-B27 KIR KIR3DL1 KIR3DS1 KIR3DL1*004 NK cell T cell

选择性前路胸腰段或腰段融合治疗青少年特发性脊柱侧凸

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中华外科杂志 2009年第10期47卷 758-761页

作者：卢文灿仉建国邱贵兴伊力哈尔·沙迪克王以朋于斌赵宏赵宇翁习生中国医学科学院北京协和医院骨科 100730 新疆维吾尔自治区人民医院脊柱外科

目的评价选择性前路胸腰段或腰段融合治疗PUMCⅡdl型（Lenke5型）青少年特发性脊柱侧凸（AIS）的临床效果。方法匝颐性分析35例行选择性前路胸腰段或腰段融合的PUMCⅡd1型（Lenke5型）AIS病例。所有病例均行前路单棒节段性固定融合，随... 详细信息

目的评价选择性前路胸腰段或腰段融合治疗PUMCⅡdl型（Lenke5型）青少年特发性脊柱侧凸（AIS）的临床效果。方法匝颐性分析35例行选择性前路胸腰段或腰段融合的PUMCⅡd1型（Lenke5型）AIS病例。所有病例均行前路单棒节段性固定融合，随访18—42个月，平均36个月。术前、术后及随访时均摄站立位全脊柱正侧位x线片，对躯干偏移、上下融合椎邻近椎间盘开角、下固定椎的倾斜、冠状面和矢状面Cobb角进行测量分析。测量数据使用SPSS11．0统计学软件进行分析。结果胸腰弯或腰弯冠状面Cobb角术前平均45．6°，术后9．7°，末次随访14．4°。胸弯冠状面Cobb角术前平均29．7°，术后17．6°，末次随访20．1°。躯干偏移术前平均14．0mm，术后14．8mm，末次随访5．1mm。下端固定椎（LIV）倾斜术前平均-21．8°，术后-1．5°，末次随访-2．1°。冠状面上端固定椎（UIV）上位椎间盘开角（UIVDA）及LIV下位椎间盘开角（LIVDA）术前分别为0．5°和0．6°，术后为0．9°和4．9°，末次随访时均显著加重，为3．0°和7．8°。矢状面胸段（T5-12）及胸腰段（T10-L2）曲度术后及末次随访时均保持良好。矢状面腰前凸（L1～S1）及固定融合节段Cobb角在术后有所减小，末次随访时均保持良好。所有病例末次随访时均未见假关节形成及其他并发症。结论选择性前路胸腰段或腰段融合是治疗PUMCⅡdl型（Lenke5型）AIS的安全、有效的方法，融合节段上、下椎间盘开角增加及部分病例残余胸弯过大现象需进一步随访评估。

关键词：脊柱侧凸青少年脊柱融合术治疗效果