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1Osteoporosis:A Silent Disease with Complex Genetic Contribution显示文摘Osteoporosis is the most common multifactorial metabolic bone disorder worldwide with a strong genetic component. In this review, the evidence for a genetic contribution to osteoporosis and related phenotypes is summarized alongside with methods used to identify osteoporosis susceptibility genes. The key biological pathways involved in the skeleton and bone development are discussed with a particular focus on master genes clustered in these pathways and their mode of action. Furthermore, the most studied single nucleotide polymorphisms(SNPs) analyzed for their importance as genetic markers of the disease are presented. New data generated by nextgeneration sequencing in conjunction with extensive meta-analyses should contribute to a better understanding of the genetic basis of osteoporosis and related phenotype variability. These data could be ultimately used for identifying at-risk patients for disease prevention by both controlling environmental factors and providing possible therapeutic targets.Maryam Marl Golchin Laleh Heidari Seyyed Mohammad Hossein Ghaderian Haleh Akhavan-Niaki 2016Journal of Genetics and Genomics2016,43,2:15
2Seismic isolation effect of lined circular tunnels with damping treatments显示文摘The Havriliak-Negami model for dynamic viscoelastic material behavior and Biot’s theory of poroelasticity are employed to develop an exact solution for three-dimensional scattering effect of harmonic plane P–SV waves from a circular cavity lined with a multilayered fluid-filled shell of infinite length containing viscoelastic damping materials and embedded within a fluid-saturated permeable surrounding soil medium. The analytical results are illustrated with numerical examples where the effects of liner/coating structural arrangement, viscoelastic material properties, liner-soil interface bonding condition, seismic excitation frequency, and angle of incidence on the induced dynamic stress concentrations are evaluated and discussed to obtain representative values of the parameters that characterize the system. It is demonstrated that incorporating viscoelastic damping materials with a low shear modulus in the constrained layer configuration is an efficient means of enhancing the overall seismic isolation performance, especially for near-normally incident seismic shear waves where the amplitudes of induced dynamic stresses may be reduced by up to one-third of those without isolation in a relatively wide frequency range. Some additional cases are considered and good agreements with solutions available in the literature are obtained.Seyyed M. Hasheminejad Amir K. Miri 2008Earthquake Engineering and Engineering Vibration2008,7,3:13
3Preliminary study on the antibacterial activity of some medicinal plants of Khuzestan(Iran)显示文摘Objective:To search for antimicrobial agents among natural products.Methods:Ethanolic extracts of 4 plant species,including Beta vulgaris L.(Chenopodiaceae),Amaranthus graecizans (A.graecizans) L.(Amaranthaceae),Rumex obtusifolius(R.obtusifolius) L.and Polygonum patulum(P.patulum) M.B.(Polygonaceae),were evaluated for antibacterial activity using agar disc diffusion method against some gram-positive and gram-negative bacteria[Pseudomonas aeruginosa(P.aeruginosa),Listeria monocytogenes(L.monocytogenes).Staphylococcus epidermidis(S.epidermidis),Staphylococcus aureus(S.aureus),Klebsiella pneumoniae(K. pneumoniae),Salmonella typhi(S.typhi),Bacillus cereus(B.cereus).Bacillus anthracis(B. anthracis),Escherichia coli(E.coli) and Streptococcus pyogenes(Str.pyogenes)].These extracts were obtained from aerial parts of the used plants.Results:The majority of these extracts had inhibitory effect at different concentrations(0.05 g/mL,0.10 g/mL,0.20 g/mL and 0.40 g/mL) against above mentioned bacteria.E.coli was the most resistant strain.The highest inhibitory zone was showed by ethanolic extract of P.patulum against Str.pyogenes(28 mm) and followed by ethanolic extract of B.vulgaris against S.epidermidis(23 mm).The extract of A.graecizans didn’t show inhibitory activity except at 0.40 g/mL against B.cereus.The minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) values of R.obtusifolius extract that was measured against Str.pyogenes were equal(MIC=MBC=5.00mg/mL).Conclusion: The findings of this study could also be as new source for antibiotics discovery and infection treatment.Haniyeh Koochak Seyyed Mansour Seyyednejad Hussein Motamedi 2010Asian Pacific Journal of Tropical Medicine2010,3,3:10
4Vehicle path tracking by integrated chassis control显示文摘The control problem of trajectory based path following for passenger vehicles is studied. Comprehensive nonlinear vehicle model is utilized for simulation vehicle response during various maneuvers in MATLAB/Simulink. In order to follow desired path, a driver model is developed to enhance closed loop driver/vehicle model. Then, linear quadratic regulator(LQR) controller is developed which regulates direct yaw moment and corrective steering angle on wheels. Particle swam optimization(PSO) method is utilized to optimize the LQR controller for various dynamic conditions. Simulation results indicate that, over various maneuvers, side slip angle and lateral acceleration can be reduced by 10% and 15%, respectively, which sustain the vehicle stable. Also, anti-lock brake system is designed for longitudinal dynamics of vehicle to achieve desired slip during braking and accelerating. Proposed comprehensive controller demonstrates that vehicle steerability can increase by about 15% during severe braking by preventing wheel from locking and reducing stopping distance.Saman Salehpour Yaghoub Pourasad Seyyed Hadi Taheri 2015Journal of Central South University2015,22,4:9
5异种搅拌摩擦焊制备铜铝合金双金属纳米复合材料显示文摘对纯铜与AA5754合金进行对接搅拌摩擦焊接。为了降低金属间化合物的有害影响,在搅拌摩擦焊(FSW)接头中添加纳米SiC强化颗粒。采用拉伸试验、显微硬度试验、扫描电镜和X射线衍射分析方法研究焊接接头的性能。结果显示,当焊接速度为50 mm/min、转速为1000 r/min时接头的性能最好。纳米SiC颗粒的存在使搅拌区(SZ)铝和铜的晶粒尺寸分别从38.3和12.4μm减小到12.9和5.1μm。含SiC纳米增强颗粒的接头其抗拉强度约为240 MPa,是铝基体的~90%。且添加SiC纳米颗粒使接头焊缝区的最高显微硬度从HV 160显著增加到HV 320。结果还表明,FSW接头中生成热的升高使Al_(4)Cu_(9)和Al_(2)Cu金属间化合物的数量增加。Farhad BAKHTIARI ARGESI Ali SHAMSIPUR Seyyed Ehsan MIRSALEHI 2021Transactions of Nonferrous Metals Society of China2021,31,5:8
6Dissimilar Joining of Pure Copper to Aluminum Alloy via Friction Stir Welding显示文摘In this study, the dissimilar friction stir welding(FSW) butt joints between aluminum alloy 5754-H114 and commercially pure copper were investigated. The thickness of welded plates was 4 mm and the aluminum plate was placed on the advancing side. In order to obtain a suitable flow and a better material mixing, a 1-mm offset was considered for the aluminum plate, toward the butt centerline. For investigating the microstructure and mechanical properties of FSWed joints, optical microscopy and mechanical tests(i.e., uniaxial tensile test and microhardness) were used, respectively.Furthermore, the analysis of intermetallic compounds and fracture surface was examined by scanning electron microscopy and X-ray diffraction. The effect of heat generation on the mechanical properties and microstructure of the FSWed joints was investigated. The results showed that there is an optimum amount of heat input. The intermetallic compounds formed in FSWed joints were Al4Cu9 and Al2Cu. The best results were found in joints with 1000 rpm rotational speed and100 mm/min travel speed. The tensile strength was found as 219 MPa, which reached 84% of the aluminum base strength.Moreover, maximum value of the microhardness of the stir zone(SZ) was attained as about 120 HV, which was greatly depended on the grain size, intermetallic compounds and copper pieces in SZ.Farhad Bakhtiari Argesi Ali Shamsipur Seyyed Ehsan Mirsalehi 2018Acta Metallurgica Sinica(English Letters)2018,31,11:7
7Antibacterial activity of eight Iranian plant extracts against methicillin and cefixime restistant Staphylococcous aureus strains显示文摘Objective:To assess the antibacterial activity of eight Iranian plant extracts against Staphylococcus aureus(S.aureus) strains which were isolated from infected patients.Methods: The studied strains were isolated from urine,stool,blood and wound of infected patients and identified by biochemical tests.In further,the antibacterial activity of 8 ethanolic local plant extracts including Querqus brantii(Q.brantii),Ziziphus spina-christi(Z.spina-christi),Peganum harmala(P.harmala),Oliveira decumbens(O.decumbens),Galium tricornutum(G.tricornutum), Vitex pseudo negundo(Vi.pseudo negundo),Salvia officinalis(S.officinalis),Vaccaria pyramidata (V.pyramidata) were then evaluated using agar disc diffusion method.Results:A total of 9 isolates were isolated and identified as S.aureus.Antibacterial profile of the strains showed that the strains were resistant to methicillin and cefixime.The highest antibacterial activity against the studied strains were belong to Q.brantii,P.harmala,Z.spina-christi and O.decumbens vent extracts with 11-40 mm,15-28 mm,8-26 mm and 10-20 mm of diameters,respectively. Intermediate antibacterial activity was exhibited by G.tricornutum and Vi.pseudo negundo against some of the studied strains with 7-20 mm and 7-13 mm of diameters,respectively. Noteworthy,out of 9 studied strains;6 and 2 of them were resistant to the G.tricornutum and Vi. pseudo negundo extracts,respectively.The S.officinalis and Va.pyramidata,however,showed no antibacterial activity against the studied strains.Conclusions:The Q.brantii,P.harmala,Z. spina-christi and O.decumbens extracts were shown to possess strong antibacterial activity against methicillin and cefixime resistant S.aureus strains and can be considered as the promising natural antibiotics for treating the studied strains.Morteza Shojaei Moghadam Susan Maleki Esmaeil Darabpour Hossein Motamedi Seyyed Mansour Seyyed Nejad 2010Asian Pacific Journal of Tropical Medicine2010,3,4:7
8Co-optimization of carbon dioxide storage and enhanced oil recovery in oil reservoirs using a multi-objective genetic algorithm(NSGA-Ⅱ)显示文摘Climate researchers have observed that the carbon dioxide(CO2) concentration in the atmosphere have been growing significantly over the past century. CO2 from energy represents about 75% of the greenhouse gas(GHG) emissions for Annex B(Developed) countries, and over 60% of global emissions. Because of impermeable cap rocks hydrocarbon reservoirs are able to sequester CO2. In addition, due to high-demand for oil worldwide, injection of CO2 is a useful way to enhance oil production. Hence, applying an efficient method to co-optimize CO2 storage and oil production is vital. Lack of suitable optimization techniques in the past led most multi-objective optimization problems to be tackled in the same way as a single objective optimization issue. However, there are some basic differences between the multi and single objective optimization methods. In this study, by using a nondominated sorting genetic algorithm(NSGA-II) for an oil reservoir, some appropriate scenarios are proposed based on simultaneous gas storage and enhanced oil recovery optimization. The advantages of this method allow us to amend production scenarios after implementing the optimization process, by regarding the variation of economic parameters such as oil price and CO2 tax. This leads to reduced risks and time duration of making new decisions based on upcoming situations.SAFARZADEH Mohammad Amin MOTAHHARI Seyyed Mahdia 2014Petroleum Science2014,11,3:6
9Wettability alteration and oil recovery by spontaneous imbibition of smart water and surfactants into carbonates显示文摘Naturally fractured carbonate reservoirs have very low oil recovery efficiency owing to their wettability and tightness of matrix.However,smart water can enhance oil recovery by changing the wettability of the carbonate rock surface from oilwet to water-wet,and the addition of surfactants can also change surface wettability.In the present study,the effects of a solution of modified seawater with some surfactants,namely C12 TAB,SDS,and TritonX-100(TX-100),on the wettability of carbonate rock were investigated through contact angle measurements.Oil recovery was studied using spontaneous imbibition tests at 25,70,and 90°C,followed by thermal gravity analysis to measure the amount of adsorbed material on the carbonate surface.The results indicated that Ca2+,Mg2+,and SO42-.ions may alter the carbonate rock wettability from oil-wet to water-wet,with further water wettability obtained at higher concentrations of the ions in modified seawater.Removal of NaCl from the imbibing fluid resulted in a reduced contact angle and significantly enhanced oil recovery.Low oil recoveries were obtained with modified seawater at 25 and 70°C,but once the temperature was increased to 90°C,the oil recovery in the spontaneous imbibition experiment increased dramatically.Application of smart water with C12 TAB surfactant at 0.1 wt%changed the contact angle from 161°to 52°and enhanced oil recovery to 72%,while the presence of the anionic surfactant SDS at 0.1 wt%in the smart water increased oil recovery to 64.5%.The TGA analysis results indicated that the adsorbed materials on the carbonate surface were minimal for the solution containing seawater with C12 TAB at 0.1 wt%(SW+CTAB(0.1 wt%)).Based on the experimental results,a mechanism was proposed for wettability alteration of carbonate rocks using smart water with SDS and C12 TAB surfactants.Saeb Ahmadi Mostafa Hosseini Ebrahim Tangestani Seyyed Ebrahim Mousavi Mohammad Niazi 2020Petroleum Science2020,17,3:6
10In vitro assay for the anti-brucella activity of medicinal plants against tetracycline-resistant Brucella melitensis显示文摘Brucellosis, a zoonosis caused by four species of brucella, has a high morbidity. Brucella melitensis is the main causative agent of brucellosis in both human and small ruminants. As an alternative to conventional antibiotics, medicinal plants are valuable resources for new agents against antibiotic-resistant strains. The aim of this study was to investigate the usage of native plants for brucellosis treatment. For this purpose, the anti-brucella activities of ethanolic and methanolic extracts of Salvia sclarea, Oliveria decumbens, Ferulago angulata, Vitex pseudo-negundo, Teucrium polium, Plantago ovata, Cordia myxa, and Crocus sativus were assessed. The activity against a resistant Br. melitensis strain was determined by disc diffusion method at various concentrations from 50-400 mg/ml. Antibiotic discs were also used as a control. Among the evaluated herbs, six plant (Salvia sclarea, Oliveria decumbens, Ferulago angulata, Vitex pseudo-negundo, Teucrium polium, and Crocus sativus) showed anti-brucella activity. Oliveria de- cumbens was chosen as the most effective plant for further studies. A tested isolate exhibited resistance to tetracycline, nafcillin, oxacillin, methicillin, and colistin. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values for Oliveria decumbens against resistant Br. melitensis were the same (5 mg/ml), and for gentamicin they were both 2 mg/ml. Time-kill kinetics for a methanolic extract of Oliveria decumbens was 7 h whereas for an ethanolic extract it was 28 h. Also, Oliveria decumbens extracts showed a synergistic effect in combination with doxycycline and tetracycline. In general, the similar values of MIC and MBC for Oliveria decumbens suggest that these extracts could act as bactericidal agents against Br. melitensis. In addition to Oliveria decumbens, Crocus sativus and Salvia sclarea also had good anti-brucella activity and these should be considered for further study.Hossein MOTAMEDI Esmaeil DARABPOUR Mahnaz GHOLIPOUR Seyyed Mansour SEYYED NEJAD 2010Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)2010,11,7:6
11第二相粒径和振动对FSP制备AZ91/SiC表面复合层的影响显示文摘采用改进的搅拌摩擦加工方法(FSP)加工AZ91镁合金试样。这种新方法称为“振动搅拌摩擦加工方法(FSVP)”。SiC纳米颗粒作为第二相粒子,利用FSP和FSVP制备合金的表面复合层,研究不同粒径(30 nm和300 nm)的SiC强化颗粒对复合材料表面不同性能的影响。结果表明,采用FSVP工艺能细化材料的显微组织,提高材料的硬度、延展性和强度等力学性能。粒径为30 nm的增强颗粒对复合材料显微组织和力学性能的影响大于粒径为300 nm的增强颗粒。振动频率越高,FSV试样的力学性能和显微组织越好;当FSV振动频率为50和25 Hz时,搅拌区硬度值分别约为157和116 MPa。Behrouz BAGHERI Mahmoud ABBASI Amin ABDOLLAHZADEH Seyyed Ehsan MIRSALEHI 2020Transactions of Nonferrous Metals Society of China2020,30,4:6
12Complementary and alternative medicine use in Iranian patients with diabetes mellitus显示文摘OBJECTIVE: There is increasing interest in complementary and alternative medicine generally, and especially by those affected by chronic diseases, such as diabetes mellitus. We aimed to determine the prevalence and pattern of complementary and alternative medicine use among patients suffering from diabetes mellitus in Shiraz, southern Iran. Another objective was to explore associated factors for use of complementary and alternative medicine among patients with diabetes mellitus.METHODS: A 19-item semi-structured questionnaire(open- and close-ended) was administered to 239 patients with diabetes mellitus in this cross-sectional study. It was carried out in two outpatient diabetes clinics affiliated with the Shiraz University of Medical Sciences, Shiraz, Iran.RESULTS: One hundred and eighty patients(75.3%) used at least one type of complementary and alternative medicine in the last year prior to the interview. Patients with diabetes mellitus who were living in a large family(≥ 5 members), not taking insulin, and believed that complementary and alternative medicine have synergistic effects with conventional medicine, were independently and significantly(P values: 0.02, 0.04, and 0.01, respectively) more likely to use complementary and alternative medicine. Most of the users(97.7%) reported use of herbal preparations, and 89.4% of users did not change their medication, neither in medication schedule nor its dosage.CONCLUSION: The use of complementary and alternative medicine, especially herbal remedies, is popular among diabetes patients in Shiraz, Iran. This use is associated with patients' family size, type of conventional medications and their view about concomitant use of complementary and conventional medicine.Mohammad Hashem Hashempur Mojtaba Heydari Seyed Hamdollah Mosavat Seyyed Taghi Heydari Mesbah Shams 2015Journal of Integrative Medicine2015,13,5:5
13Humidity sensing properties of Ce-doped nanoporous ZnO thin film prepared by sol-gel method显示文摘The humidity sensitive characteristics of the sensor fabricated from Ce-doped nanoporous ZnO by screen-printing on the alumina substrate with Ag-Pd interdigital electrodes were investigated at different sintering temperatures.The nanoporous thin films were prepared by sol-gel technique.It was found that the impedance of the sensor sintered at 600 oC changed more than four order of magnitude in the relative humidity(RH) range of 11%-95% at 25 oC.The response and recovery time of the sensor were about 13 and 17 s,respectively.The sensor showed high humidity sensitivity,rapid response and recovery,prominent stability,good repeatability and narrow hysteresis loop.These re-sults indicated that Ce-doped nanoporous ZnO thin films can be used in fabricating high-performance humidity sensors.Mansoor Anbia Seyyed Ebrahim Moosavi Fard 2012Journal of Rare Earths2012,30,1:5
14Environmental Suitability and Distribution of the Caucasian Rock Agama,Paralaudakia caucasia (Sauria:Agamidae) in Western and Central Asia显示文摘Predictive potential distribution modeling is crucial in outlining habitat usage and establishing conservation management priorities.In this paper we provide detailed data on the distribution of the Caucasian rock agama Paralaudakia caucasia,and use species distribution models(MAXENT) to evaluate environmental suitability and potential distribution at a broad spatial scale.Locality data on the distribution of P.caucasia have been gathered over nearly its entire range by various authors from f ield surveys.The distribution model of P.caucasia showed good performance(AUC=0.887),and predicted high suitability in regions mainly located in Tajikistan,north Pakistan,Afghanistan,southeast Turkmenistan,northeast Iran along the Elburz mountains,Transcaucasus(Azerbajan,Armenia,Georgia),northeastern Turkey and northward along the Caspian Sea coast in Daghestan,Russia.The identifi cation of suitable areas for this species will help to assess conservation status of the species,and to set up management programs.Seyyed Saeed HOSSEINIAN YOUSEFKHANI Gentile Francesco FICETOLA Nasrullah RASTEGAR-POUYANI Natalia B ANANJEVA Eskandar RASTEGAR-POUYANI Rafaqat MASROOR 2013Asian Herpetological Research2013,4,3:4
15Targeting cell signaling in allergic asthma显示文摘Asthma is chronic inflammation of the airways characterized by airway hyper-responsiveness,wheezing,cough,and dyspnea.Asthma affects>350 million people worldwide.The Th2 immune response is a major contributor to the pathophysiology of asthma.Targeted therapy modulating cell signaling pathways can be a powerful strategy to design new drugs to treat asthma.The potential molecular pathways that can be targeted include IL-4-IL-13-JAK-STAT-MAP kinases,adiponectin-iNOS-NF-κB,PGD2-CRTH2,IFNs-RIG,Wnt/β-catenin-FAM13A,FOXC1-miR-PI3K/AKT,JNK-Gal-7,Nrf2-ROS,Foxp3-RORγt,CysLTR,AMP,Fas-FasL,PTHrP/PPARγ,PAI-1,FcɛRI-LAT-SLP-76,Tim-3-Gal-9,TLRs-MyD88,PAR2,and Keap1/Nrf2/ARE.Therapeutic drugs can be designed to target one or more of these pathways to treat asthma.Seyyed Shamsadin Athari 2019Signal Transduction and Targeted Therapy2019,4,1:4
16Antimicrobial properties of Teucrium polium against some clinical pathogens显示文摘Objective:To explore the antibacterial effect of the alcoholic extracts of aerial parts of Teucrium polium,native in Iran on some pathogenic bacteria.Methods:Antibacterial activity of ethanolic extract(50 to 400 mg/mL) and methanolic extract(400 and 600 mg/mL) was evaluated by disc diffusion method.Results:The ethanolic extract results showed that Bacillus anthracis was the most sensitive species,while Escherichia coli and Proteus mirabilis were more resistant than others.In the case of the methanolic extract,Bordetella bronchiseptica was the most sensitive and Proteus mirabilis and Arcanobacterium pyogenes were the most resistant species.The hydroalcoholic extract of Teucrium polium had a relatively satisfactory effect on Salmonella typhi. The minimal inhibitory concentration(MIC) of Staphylococcus aureus and Salmonella typhi was 40 mg/mL and Bordetella bronchiseptica and Bacillus anthracis was 10 mg/mL.The minimal bactericidal concentration(MBC) against Bacillus anthracis was 10 mg/mL while against other species were not found(>200 mg/mL).The methanolic extract had also synergistic effect with methicillin,vancomycin against Staphylococcus aureus and with novobiocin against Salmonella typhi.Conclusions:These results suggest that this plant contains relatively good antibacterial activity and it can be used as a source of antiseptic compounds for medicinal uses.Esmaeil Darabpour Hossein Motamedi Seyyed Mansour Seyyed Nejad 2010Asian Pacific Journal of Tropical Medicine2010,3,2:4
17A survey on Hibiscus rosa-sinensis,Alcea rosea L.and Malva neglecta Wallr as antibacterial agents显示文摘Objective:To guide for selection of plants with antibacterial activity for further phytochemical works on the isolation and identification of the active compounds.Methods:Ethanolic extracts of 3 species from Malvaceae family were evaluated by agar disc diffusion method for antibacterial activity against some gram-positive and gram-negative bacteria(Pseudomonas aeruginosa,Listeria monocytogenes,Staphylococcus epidermidis.Staphylococcus aureus, Klebsiella pneumoniae.Salmonella typhi,Bacillus cereus.Bacillus anthracis,Escherichia coli and Streptococcus pyogenes).The extracts were obtained from aerial parts of Hibiscus rosa(H. rosa)-sinensis(leaf and flower),Alcea rosea(A.rosea) L.(leaf and flower) and Malva neglecta(M. neglecta) Wallr(flower).Results:These extracts had inhibitory effects at different concentrations (0.05,0.10,0.20 and 0.40 g/mL) against above mentioned bacteria.Escherichia coli was the most resistant strain.The highest inhibitory zone was showed by ethanolic extract of M.neglecta against Staphylococcus epidermidis(22 mm) and followed by ethanolic extract from flower of H.rosa against Staphylococcus epidermidis and Staphylococcus aureus(20 mm).The Minimum Inhibitory Concentration(MIC) and Minimum Bactericidal Concentration(MBC) values against Staphylococcus epidermidis were equal(M1C=MBC=5 mg/mL for M.neglecta extract and for H. rosa extract MIC=MBC=20 mg/mL).Conclusions:These findings suggest that these native plants have good antibacterial properties that can be used for infection control and treatment and could also be as new source for antibiotics discovery and infection treatment.Seyyed Mansour Seyyednejad Haniyeh Koochak Esmaeil Darabpour Hossein Motamedi 2010Asian Pacific Journal of Tropical Medicine2010,3,5:4
18Modeling of fluid-induced vibrations and identification of hydrodynamic forces on flow control valves显示文摘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%.Samad Mehrzad Ilgar Javanshir Ahmad Rahbar Ranji Seyyed Hadi Taheri 2015Journal of Central South University2015,22,7:3
19CFD modeling of a spouted bed with a porous draft tube显示文摘Spouted bed with a porous draft tube is used for drying of grains and chemical products and thermal disinfestations process.This work provides a computational fluid dynamics(CFD)simulation of binary mixtures of glass particles in a spouted bed with a porous draft tube.The simulation used the multi-fluid Eulerian-Eulerian approach based on kinetic theory of granular flows,incorporating a kinetic-frictional constitutive model for dense assemblies of particulate solids and Gidaspow's drag model for the inter-action between gas and particles.Influences of solids mass fraction and inlet gas flow rate on pressure distribution,gas and particle velocities were studied.The modeling results were compared with the exper-imental work of Ishikura,Nagashima,and Ide(2003)for the flow condition along the axis of the spouted bed.Good agreement between the modeling results and experimental data was observed.Salar Azizi Seyyed Hossein Hosseini M.Moraveji Goodarz Ahmadi 2010Particuology2010,8,5:3
20Facile synthesis of nanoporous CuS nanospheres for high-performance supercapacitor electrodes显示文摘In recent years, development of high-performance supercapacitor electrode materials has stimulated a great deal of scientific research. The electrochemical performance of a supercapacitor strongly depends on its material structures. Herein, we report a simple strategy for high-performance supercapacitors by building pseudocapacitive CuS nanospheres with nanoporous structures, nanosized walls(<10 nm) and relatively large specific surface area of 65 m^2/g. This electrode demonstrates excellent electrochemical performance including a maximum specific capacitance of 814 F/g at 1 A/g, significant rate capability of 42% capacitance retention at an ultrafast rate of 50 A/g, and outstanding long-term cycling stability at various current densities. The remarkable electrochemical performance of as-prepared nanoporous CuS nanospheres electrode has been attributed to its unique structures that plays a key role in providing short ion and electron diffusion pathways, facilitated ion transport and more active sites for electrochemical reactions. This work sheds a new light on the metal sulfides design philosophy, and demonstrates that nanoporous CuS nanospheres electrode is a promising candidate for application in high-performance supercapacitors.Hamid Heydari Seyyed Ebrahim Moosavifard Mohammad Shahraki Saeed Elyasi 2017Journal of Energy Chemistry2017,26,4:3
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