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| 1 | Effects of Fe_2O_3 Nanoparticles on Water Permeability and Strength Assessments of High Strength Self-Compacting Concrete显示文摘In this work,compressive,flexural and split tensile strength together with coefficient of water absorption of high performance self-compacting concrete containing different amount of Fe2O3 nanoparticles have been investigated.The strength and the water permeability of the specimens have been improved by adding Fe2O3 nanoparticles in the cement paste up to 4.0 wt%.Fe2O3 nanoparticle as a foreign nucleation site could accelerate C-S-H gel formation as a result of increased crystalline Ca(OH)2 amount especially at the early age of hydration and hence increase the strength of the specimens.In addition,Fe2O3 nanoparticles are able to act as nanofillers and recover the pore structure of the specimens by decreasing harmful pores to improve the water permeability.Several empirical relations have been presented to predict the flexural and the split tensile strength of the specimens by means of the corresponding compressive strength at a certain age of curing.Accelerated peak appearance in conduction calorimetry tests,more weight loss in thermogravimetric analysis and more rapid appearance of peaks related to hydrated products in X-ray diffraction results indicate that Fe2O3 nanoparticles up to 4 wt% could improve the mechanical and the physical properties of the specimens. | Ali Khoshakhlagh Ali Nazari Gholamreza Khalaj | 2012 | Journal of Materials Science & Technology2012，28，1： | 11 |
| 2 | Fatty liver index vs waist circumference for predicting non-alcoholic fatty liver disease显示文摘AIM: To determine the discriminatory performance of fatty liver index(FLI) for non-alcoholic fatty liver disease(NAFLD).METHODS: The data of 5052 subjects aged over 18 years were analyzed. FLI was calculated from body mass index, waist circumference(WC), triglyceride, and gamma glutamyl transferase data. Logistic regression analysis was conducted to determine the association between FLI and NAFLD. The discriminatory performance of FLI in the diagnosis of NAFLD was evaluated by receiver operating characteristic analysis. Area under the curves(AUCs) and related confidence intervals were estimated. Optimal cutoff points of FLI in the diagnosis of NAFLD were determined based on the maximum values of Youden's index.RESULTS: The mean age of men and women in the study population were 44.8 ± 16.8 and 43.78 ± 15.43, respectively(P = 0.0216). The prevalence of NAFLD was 40.1% in men and 44.2% in women(P < 0.0017). FLI was strongly associated with NAFLD, so that even a one unit increase in FLI increased the chance of developing NAFLD by 5.8%(OR = 1.058, 95%CI: 1.054-1.063, P < 0.0001). Although FLI showed good performance in the diagnosis of NAFLD(AUC = 0.8656(95%CI: 0.8548-0.8764), there was no significant difference with regards to WC(AUC = 0.8533, 95%CI: 0.8419-0.8646). The performance of FLI was not significantly different between men(AUC = 0.8648, 95%CI: 0.8505-0.8791) and women(AUC = 0.8682, 95%CI: 0.8513-0.8851). The highest performance with regards to age was related to the 18-39 age group(AUC = 0.8930, 95%CI: 0.8766-0.9093). The optimal cutoff points of FLI were 46.9 in men(sensitivity = 0.8242, specificity = 0.7687, Youden's index = 0.5929) and 53.8 in women(sensitivity = 0.8233, specificity = 0.7655, Youden's index = 0.5888).CONCLUSION: Although FLI had acceptable discriminatory power in the diagnosis of NAFLD, WC was a simpler and more accessible index with a similar performance. | Nima Motamed Masoudreza Sohrabi Hossein Ajdarkosh Gholamreza Hemmasi Mansooreh Maadi Fatemeh Sima Sayeedian Reza Pirzad Khadijeh Abedi Sivil Aghapour Mojtaba Fallahnezhad Farhad Zamani | 2016 | World Journal of Gastroenterology2016，22，10： | 8 |
| 3 | TIRAP rs8177374 gene polymorphism increased the risk of pulmonary tuberculosis in Zahedan,southeast Iran显示文摘Objective:To evaluate the possible association between Toll-interleukin 1 receptor(TIR) domain containing adaptor protein(TIRAP;also known as MAI.) rsl893352 and rs8l77374(S180L) gene polymorphisms and pulmonary tuberculosis(PTB) in a sample of Iranian population.Methods:This case-control study was performed on 174 PTB and 177 healthy subjects.Tetra amplification refractory mutation systetn-polymerase chain reaction(T-AKMS-PCR) was used to detect the polymorphisms.Results:Our finding showed that neither the overall Ckisqaare comparison of PTB and control subjects nor the logistic regression analysis indicated any association between rsl893352 polymorphism and PTB.Regarding rs8l77374 polymorphism,the CT genotype as well as CT+TT increased the risk of PTB in comparison with CC genotype(OR=4.73,95%CI=2.65-8.45,P<0.0001 and OR=6.47,95%C1=3.68-11.38,P<0.0001.respectively).The rs8177374 T allele increased the risk of PTB in comparison with C allele(OR=4.21.95%CI=2.43-7.26,P<0.0001).Conclusions:Our finding indicates that TIRAP rs8177374 polymorphism is associated with PTB in a sample of Iranian population. | Mohammad Naderi Mohammad Hashemi Zahra Pourmontaseri Ebrahim Eskari-Nasab Gholamreza Bahari Mohsen Taheri | 2014 | Asian Pacific Journal of Tropical Medicine2014，7，6： | 8 |
| 4 | Efficacy and safety of Amla(Phyllanthus emblica L.) in non-erosive reflux disease:a double-blind,randomized,placebo-controlled clinical trial显示文摘Background: Gastroesophageal reflux disease(GERD) is one of the most common gastrointestinal complaints. GERD, caused by the reflux of stomach contents into the esophagus, leads to troublesome symptoms such as heartburn and regurgitation. It is classified into two types: erosive esophagitis,characterized by visible esophageal mucosa erosion in endoscopy, and non-erosive reflux disease(NERD). GERD is a chronic and recurrent disease that impairs the quality of life and imposes socioeconomic and therapeutic burdens to both patients and society.Objective: Due to the failure of the conventional treatments for GERD and to the traditional use of Amla(Phyllanthus emblica L.), in addition to beneficial effects shown in recent studies, we evaluated the safety and efficacy of Amla tablet for improvement of symptoms of patients with NERD.Design, setting, participants and interventions: We designed a double-arm, randomized, double-blind,placebo-controlled clinical trial. Sixty-eight patients who had classic symptoms of GERD(heartburn,regurgitation and epigastralgia) for at least three months before the start of the trial were randomized in two parallel groups. Patients in the Amla group received two 500 mg Amla tablets twice a day, after meals,for 4 weeks. In the control group, patients received placebo tablets similar to the Amla prescription.Main outcome measures: The patients were visited at baseline, and at the end of the 2 nd and 4 th weeks of intervention; their symptoms were measured on a frequency and severity scale for the symptoms of NERD,according to the quality of life in reflux-associated disease questionnaire.Results: Frequencies of heartburn and regurgitation in both groups of the study were significantly reduced after intervention(P < 0.001). Repeated measures logistic regression analysis showed that, in the Amla group, there was a more significant reduction in regurgitation frequency, heartburn frequency, regurgitation severity and heartburn severity during the study period, compared with the placebo group(P < 0.001).Conclusion: This randomized double-blind, placebo-controlled clinical trial demonstrated that Amla could reduce frequencies of heartburn and regurgitation and improve heartburn and regurgitation severity in patients with NERD. | Shahnaz Karkon Varnosfaderani Fataneh Hashem-Dabaghian Gholamreza Amin Mahbubeh Bozorgi Ghazaleh Heydarirad Esmaeil Nazem Mohsen Nasiri Toosi Seyed Hamdollah Mosavat | 2018 | Journal of Integrative Medicine2018，16，2： | 7 |
| 5 | Scientific and technical aspects of yogurt fortification:A review显示文摘Food fortification is one of the most important processes for improvement of the nutrients quality and quantity in food.It can be a very cost effective public health intervention.Due to the high consumption rate of dairy products such as yogurt,fortification of these products will effectively reduce or prevent diseases associated with nutritional deficiencies.The aim of this investigation is to study the technical aspects involved in production of different types of fortified yogurts and their role in disease prevention and correction of deficiencies.In this paper,firstly,fortification is defined and the main reasons behind carrying out this process are presented and then yogurt production process and a variety of minerals,vitamins,and functional ingredients which are used in the process are briefly discussed.©2015 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved. | Hadi Hashemi Gahruie Mohammad Hadi Eskandari Gholamreza Mesbahi Mohammad Amin Hanifpour | 2015 | Food Science and Human Wellness2015，4，1： | 7 |
| 6 | Expression of Acyl-lipid 12-desaturase Gene in Prokaryotic and Eukaryotic Cells and Its Effect on Cold Stress Tolerance of Potato显示文摘We report the expression profile of acyl-lipid 12-desaturase (desA) gene from Synechocystis sp. PCC6803 and its effect on cell membrane lipid composition and cold tolerance in prokaryotic (Escherichia coli) and eukaryotic (Solanum tuberosum) cells. For this purpose, a hybrid of desA and reporter gene encoding thermostable lichenase (licBM3) was constructed and used to transform these cells. The expression of this hybrid gene was measured using qualitative (Petri dish test, electrophoregram and zymogram) and quantitative methods (spectrometry and gas liquid chromatography assays). The maximum level of linoleic acid in the bacterial cells containing hybrid gene was 1.9% of total fatty acids. Cold stress tolerance assays using plant damage index and growth parameters showed that cold tolerance was enhanced in primary transgenic lines because of increased unsaturated fatty acid concentration in their lipids. The greatest content of 18:2 and 18:3 fatty acids in primary transgenic plants was observed for lines 2 (73%) and 3 (41%). Finally, our results showed that desaturase could enhance tolerance to cold stress in potato, and desaturase and lichenase retain their functionality in the structure of the hybrid protein where the enzymatic activity of target gene product was higher than in the case of reporter lichenase gene absence in the construction. | Reza Maali Amiri Natalia O. Yur'eva Khristina R. Shimshilashvili Irina V. Goldenkova-Pavlova Vasiliy P. Pchelkin Elmira I. Kuznitsova Vladimir D. Tsydendambaev Tamara I. Trunova Dmitry A. Los Gholamreza Salehi Jouzani Alexander M. Nosov | 2010 | Journal of Integrative Plant Biology2010，52，3： | 6 |
| 7 | Daily and Monthly Suspended Sediment Load Predictions Using Wavelet Based Artificial Intelligence Approaches显示文摘In the current study, the efficiency of Wavelet-based Least Square Support Vector Machine(WLSSVM) model was examined for prediction of daily and monthly Suspended Sediment Load(SSL) of the Mississippi River. For this purpose, in the first step, SSL was predicted via ad hoc LSSVM and Artificial Neural Network(ANN) models; then,streamflow and SSL data were decomposed into subsignals via wavelet, and these decomposed sub-time series were imposed to LSSVM and ANN to simulate discharge-SSL relationship. Finally, the ability of WLSSVM was compared with other models in multistep-ahead SSL predictions. The results showed that in daily SSL prediction, LSSVM has better outcomes with Determination Coefficient(DC)=0.92 than ad hoc ANN with DC=0.88. However unlike daily SSL, in monthly modeling, ANN has a bit accurate upshot.WLSSVM and wavelet-based ANN(WANN) models showed same consequences in daily and different in monthly SSL predictions, and adding wavelet led to more accuracy of LSSVM and ANN. Furthermore,conjunction of wavelet to LSSVM and ANN evaluated via multi-step-ahead SSL predictions and, e.g.,DC LSSVM=0.4 was increased to the DC WLSSVM=0.71 in 7-day ahead SSL prediction. In addition, WLSSVM outperformed WANN by increment of time horizon prediction. | Vahid NOURANI Gholamreza ANDALIB | 2015 | Journal of Mountain Science2015，12，1： | 6 |
| 8 | Galerkin法研究磁场和热辐射作用下的非牛顿纳米流体在垂直平板间的流动和自然对流换热特性(英文)显示文摘研究了在磁场和热辐射作用下,非牛顿纳米流体在两个无限大的垂直平板间流动的自然对流换热和流动特性。首先,采用相似变换法,将偏微分形式的动量和能量守恒方程转化为特殊边界条件下的非线性常微分方程组。应用Galerkin方法(GM),获得非线性常微分方程组的解析解,并给出了非线性常微分方程组的数值解。对比分析解析解和数值解,验证了模型的准确性、精度和可靠性。最后,综合考虑了磁场、辐射参数和纳米流体体积分数等参数对速度、摩擦阻力系数和Nusselt数分布的影响。结果表明,随着磁力作用的增大,速度场、摩擦阻力系数和热性能下降。辐射参数虽然对增强的速度场影响不大,但降低了摩擦阻力系和Nusselt数的影响。 | Peyman MAGHSOUDI Gholamreza SHAHRIARI Hamed RASAM Sadegh SADEGHI | 2019 | Journal of Central South University2019，26，5： | 6 |
| 9 | Blastability evaluation for rock mass fragmentation in Iran central iron ore mines显示文摘In this research, we investigated the influence of rock mass properties, blast design parameters and explosive properties on blast fragmentation. Rock mass properties were evaluated in 51 blasting blocks using engineering geological mapping of 1961 meters of the scanline, experiments on intact rock samples and measuring P-wave velocity(Vp) for 1771 meters of seismic profiles. The results indicate that increasing spacing, persistence, opening, roughness, waviness of discontinuities, and Vp and uniaxial compressive strength(UCS) of intact rock as well as the increase of discontinuities angle with the bench face of blasting block will increase the size distribution of blasted rocks. In addition, evaluation of the influence of connector type, specific drilling and specific charge has shown that using the Nonel system will decrease the mean size of fragmentation. It is also demonstrated that increasing specific drilling and specific charge quantities will result in the increase of mean size of fragmentation. | Akbari Majid Lashkaripour Gholamreza Yarahamdi Bafghi Alireza Ghafoori Mohammad | 2015 | International Journal of Mining Science and Technology2015，25，1： | 5 |
| 10 | Optimal vector-valued intensity measure for seismic collapse assessment of structures显示文摘The present study is aimed to investigate the ability of different intensity measures(IMs), including response spectral acceleration at the fundamental period of the structure, S a(T1), as a common scalar IM and twelve vector-valued IMs for seismic collapse assessment of structures. The vector-valued IMs consist of two components, with S a(T1) as the first component and different parameters that are ratios of scalar IMs, as well as the spectral shape proxies εSa and N p, as the second component. After investigating the properties of an optimal IM, a new vector-valued IM that includes the ratio of S a(T1) to the displacement spectrum intensity(DSI) as the second component is proposed. The new IM is more efficient than other IMs for predicting the collapse capacity of structures. It is also sufficient with respect to magnitude, source-to-site distance, and scale factor for collapse capacity prediction of structures. To satisfy the predictability criterion, a ground motion prediction equation(GMPE) is determined for S a(T1)/DSI by using the existing GMPEs. Furthermore, an empirical equation is proposed for obtaining the correlation between the components of the proposed IM. The results of this study show that using the new vector-valued IM leads to a more reliable seismic collapse assessment of structures. | Masood Yakhchalian Ahmad Nicknam Gholamreza Ghodrati Amiri | 2015 | Earthquake Engineering and Engineering Vibration2015，14，1： | 5 |
| 11 | The risk of wound infection after simple hand laceration显示文摘BACKGROUND: This prospective observational study aimed to determine the infection rate of simple hand laceration(SHL), and to compare infection rates between patients who were prescribed antibiotics and those who were not.METHODS: The study was performed at two urban hospitals enrolling 125 emergency department(ED) patients with SHL. Exclusion criteria included patients with lacerations for more than 12 hours, immunocompromized patients, patients given antibiotics, and patients with gross contamination, bites or crush injuries. Wound infection was defined as clinical infection at a follow-up visit(10–14 days) or wound was treated with antibiotics. Patient satisfaction was also measured using a visual analogue scale 1–10, asking the patients about wound appearance. Demographic data and wound characteristics were compared between the infected and non-infected wounds. The infection rates were also compared between patients who received prophylactic antibiotics and those who did not. The results were presented with medians and quartiles or percentages with 95% confidence intervals(CI).RESULTS: In the 125 patients with SHL [median age: 28(18, 43); range: 1–102 years old; 36% female], 44(35%, 95% CI: 27%–44%) were given antibiotics in the ED. Wound infection was reported in 6 patients(4.8%, 95% CI: 2%–10%). Age, gender, history of diabetes and wound closure were not associated with wound infection(P>0.05). The infection rate was not significantly different between patients with or without antibiotic prophylaxis [7%(3/44), 95% CI: 2%–10% vs. 4%(3/81), 95% CI: 1%–11%, P=0.66]. Patient's satisfaction with appearance ofinfected and non-infected wounds were significantly different [7.5(6, 8) vs. 9(8, 10), P=0.01].CONCLUSION: Approximately 5% of simple hand lacerations become infected. Age, gender, diabetes, prophylactic antibiotics and closure technique do not affect the risk ofinfection. | Gholamreza S Roodsari Farhad Zahedi Shahriar Zehtabchi | 2015 | World Journal of Emergency Medicine2015，6，1： | 5 |
| 12 | Effect of oral garlic on arterial oxygen pressure in children with hepatopulmonary syndrome显示文摘瞄准:与肝肺症候群在孩子在动脉的氧压力上学习口头的大蒜的效果。方法:在一种囊形式的大蒜粉末与肝肺症候群被给 15 个孩子(由对比回响心动描记法证实了) 在 1 g/1.73 m (2 ) 的剂量每天。病人们每四个星期临床上并且由动脉的血气体被评估。结果:大蒜囊与肝肺症候群予 15 个病人被以。与 9.4+/-3.9 年的吝啬的年龄有 10 个男孩和 5 个女孩。内在的问题是胆道闭锁(4 个病人) ,自体免疫的肝炎(4 个病人) ,起因不明的肝硬化(4 个病人) 和 presinusoidal 门静脉高血压(3 个病人) 。八个病人(53.3%) 在他们的吝啬的动脉的氧压力显示出 10 毫米汞柱的增加。基线 PaO (2 ) 在非应答者组是在应答者组和 47.1+/-11.2 毫米汞柱的 65.6+/-12.1 毫米汞柱。在治疗的目的,在应答者和非应答者的吝啬的 PaO (2 ) 是 92.2+/-7.75 毫米汞柱和 47.5+/-11.87 毫米汞柱,分别地(P<0.01 ) 。结论:大蒜可以增加氧化并且与肝肺症候群在孩子改进呼吸困难。 | Mehri Najafi Sani Hamid Reza Kianifar Abdolrazagh Kianee Gholamreza Khatami | 2006 | World Journal of Gastroenterology2006，12，15： | 5 |
| 13 | 基于粘聚区模型的电阻点焊搭接失效模拟(英文)显示文摘本文主要研究电阻点焊(RSW)连接薄壁单搭接头在拉伸载荷作用下的断裂过程。对3组不同节点结构的搭接头进行试验,以获得接头的拉伸性能。为了模拟焊接接头的拉伸行为,首先采用二维轴对称有限元模型计算焊接过程中产生的残余应力,然后将结果转化为三维模型作为预应力。在此基础上,采用粘聚区模型(CZM)对拉伸载荷作用下模型中的断裂进行数值模拟。采用拉皮法和剪切搭接法提取粘聚区参数。用于模拟单搭接点焊试样的变形和失效的结果表明,在模拟变形和断裂载荷时,考虑残余应力的影响对保证预测结果的准确性是必要的。 | Mohammad Ali Saeimi SADIGH Gholamreza MARAMI Bahman PAYGOZAR | 2018 | Journal of Central South University2018，25，11： | 5 |
| 14 | Medicinal properties of Peganum harmala L. in traditional Iranian medicine and modern phytotherapy: a review显示文摘OBJECTIVE: To review the pharmacological activities of Peganum harmala L.(P. harmala, Nitrariaceae) in traditional Iranian medicine(TIM) and modern phytotherapy.METHODS: Opinions of TIM and modern phytotherapy about safety and acceptable dosage of this plant are discussed. Various medical properties of P.harmala were collected from important TIM references and added to scientific reports derived from modern medical databases like Pub Med, Scirus, Science Direct and Scopus.RESULTS: The main medicinal part of the plant is the seed. In TIM resources, this plant possesses various Pharmacological activities such as carminative,galactagogue, diuretic, emmenagogue, antithrom-botic and analgesic. In modern phytotherapy, P. harmala demonstrated numerous medicinal effects including cardiovascular, neurologic, antimicrobial,insecticidal, antineoplasmic, antiproliferative, gastrointestinal and antidiabetic effects. Adverse events such as neuro-sensorial symptoms, visual hallucination, bradycardia, hypotension, agitation,tremors, ataxia, abortion and vomiting cause people to use this plant cautiously. P. harmala is contraindicated during pregnancy, due to its abortive and mutagenic activities. Because of increasing the expression of CYP1A2, 2C19, and 3A4 and inhibition of monoamine oxidase, the pharmacokinetic parameters of drugs which are mainly metabolized by these enzymes may be affected by P. harmala.CONCLUSION: The medicinal properties declared for this plant in TIM are compared with those showed in modern phytotherapy. Some of the TIM properties were confirmed in modern phytotherapy like emetic and analgesic activities and some have not been evaluated in modern phytotherapy such as its therapeutic effects on paralysis, epilepsy and numbness. Finally, the current review provides the evidence for other researchers to use TIM properties of P. harmala as an efficacious natural drug.Further preclinical and clinical studies for adequate evaluating safety and therapeutic efficacy are recommended. | Mina Cheraghi Niroumand Mohammad Hosein Farzaei Gholamreza Amin | 2015 | Journal of Traditional Chinese Medicine2015，35，1： | 5 |
| 15 | Effects of heat treatment on the intermetallic compounds and mechanical properties of the stainless steel 321–aluminum 1230 explosive-welding interface显示文摘The effects of heat treatment on the microstructure and mechanical properties of intermetallic compounds in the interface of stainless steel 321 explosively bonded to aluminum 1230 were investigated in this study. Experimental investigations were performed by optical microscopy, scanning electron microscopy, and microhardness and shear tensile strength testing. Prior to heat treatment, increasing the stand-off distance between samples from 1 to 2.5 mm caused their interface to become wavy and the thickness of intermetallic layers to increase from 3.5 to 102.3 μm. The microhardness increased from HV 766 in the sample prepared at a stand-off distance of 1 mm to HV 927 in the sample prepared at a stand-off distance of 2.5 mm; in addition, the sample strength increased from 103.2 to 214.5 MPa. Heat treatment at 450°C for 6 h increased the thickness of intermetallic compound layers to 4.4 and 118.5 μm in the samples prepared at stand-off distances of 1 and 2.5 mm, respectively. These results indicated that increasing the duration and temperature of heat treatment decreased the microhardness and strength of the interface of explosively welded stainless steel 321-Al 1230 and increased the thickness of the intermetallic region. | Mohammadreza Khanzadeh Gharah Shiran Gholamreza Khalaj Hesam Pouraliakbar Mohamma dreza Jandaghi Hamid Bakhtiari Masoud Shirazi | 2017 | International Journal of Minerals,Metallurgy and Materials2017，24，11： | 4 |
| 16 | Prediction of face advance rate and determination of the operation efficiency in retreat longwall mining panel using rock engineering system显示文摘A new approach for prediction of face advance rete (FAR) prior to mining operation and determination of the operation efficiency after mining operation in retreat longwall mining panel is presented based upon the concepts of rock engineering system (RES). For this purpose, six longwall panels considered in Parvadeh-I coal mine. Seven major effective parameters on FAR was selected including coal mine roof rating, gas propagation, safety factor of longwall face, ratio of joint spacing to cutting depth at longwall face, longwall face inclination, panel width, floor rock mass rating. To performance evaluation of the presented model, the relationship between the average vulnerability indexes of advance operation with FAR was determined in considered panels with coefficient of determination (R2) equal to 0.884 that indicate relatively acceptable correlation and compatibility. Investigations of the research indicated that it is possible to determine the actual operation efficiency under fair conditions by a RES-based model. The inevitable reduction of FAR for each longwall panel was determined by presented model that the difference amount between the maximum possible practical face advance rate (FARmpp) and recorded actual face advance rate (FARa) indicate the operation efficiency. Applied approach in this paper can be used to prediction of FAR in retreat longwall mining panel for same conditions that can have many benefits, including better and more accurate planning for the sales market and mine operation. Also, presented method in this paper can be applied as a useful tool to determination of actual operation efficiency for other sections and extraction methods in coal mines. | Sajjad Aghababaei Hossein Jalalifar Gholamreza Saeedi | 2019 | International Journal of Coal Science & Technology2019，6，3： | 4 |
| 17 | A reliability study of springback on the sheet metal forming process under probabilistic variation of prestrain and blank holder force显示文摘This work deals with a reliability assessment of springback problem during the sheet metal forming process. The effects of operative parameters and material properties, blank holder force and plastic prestrain, on springback are investigated. A generic reliability approach was developed to control springback. Subsequently, the Monte Carlo simulation technique in conjunction with the Latin hypercube sampling method was adopted to study the probabilistic springback. Finite element method based on implicit/explicit algorithms was used to model the springback problem. The proposed constitutive law for sheet metal takes into account the adaptation of plastic parameters of the hardening law for each prestrain level considered. Rackwitz-Fiessler algorithm is used to find reliability properties from response surfaces of chosen springback geometrical parameters. The obtained results were analyzed using a multi-state limit reliability functions based on geometry compensations. | Hatem Mrad Mohamed Bouazara Gholamreza Aryanpour | 2013 | Acta Mechanica Sinica2013，29，4： | 4 |
| 18 | 焊后热处理对爆炸焊接青铜–碳钢界面组织和冶金性能的影响(英文)显示文摘研究了焊后热处理对青铜–碳钢爆炸结合界面组织和冶金性能的影响。在不同装药条件下,分别在1.5 mm和2 mm距离下进行了爆炸焊接。在250℃和500℃的炉中进行4和16 h的焊后热处理,再进行风冷处理。采用光学显微镜、扫描电子显微镜和显微硬度测试对焊接试样进行了实验研究。显微组织测试表明,随着距离的增加和装药量的增加,青铜与钢的界面逐渐变薄。显微硬度测试结果表明,由于爆炸力引起的强烈塑性变形,接头界面附近的硬度较高。结果表明,随着热处理温度的升高和热处理时间的延长,金属间化合物的层厚增加,金属间化合物中的铁含量降低,铜和锡的扩散越快,金属间化合物中的铁含量越低。同时,由于热处理温度的升高和热处理时间的延长,内部应力释放,界面硬度降低。 | KHANZADEH GHARAHSHIRAN Mohammad Reza KHOSHAKHLAGH Ali KHALAJ Gholamreza BAKHTIARI Hamid BANIHASHEMI Ali Reza | 2018 | Journal of Central South University2018，25，8： | 4 |
| 19 | Effect of periocular injection of celecoxib and propranolol on ocular level of vascular endothelial growth factor in a diabetic mouse model显示文摘AIM: To investigate the effects of periocular injection of propranolol and celecoxib on ocular levels of vascular endothelial growth factor(VEGF) in a diabetic mouse model.METHODS: Forty 4-6wk BALB-C male mice weighing20-25 g were used. The study groups included: non-diabetic control(group 1), diabetic control(group 2),diabetic propranolol(group 3), and diabetic celecoxib(group 4). After induction of type 1 diabetes by streptozotocin, propranolol(10 μg) and celecoxib(200 μg dissolved in carboxymethylcellulose 0.5%) were injected periocularly. The ocular level of VEGF was measured in all the study groups using enzyme-linked immuno sorbent assay(ELISA) method. RESULTS: Ocular VEGF level was significantly increased(1.25 fold) in the diabetic control group when compared to the non-diabetic group one week after induction with streptozotocin(P =0.002). Both periocular propranolol and celecoxib significantly reduced ocular VEGF levels(P =0.047 and P <0.001, respectively). The effect was more pronounced with celecoxib. CONCLUSION: The periocular administration of propranolol and celecoxib can significantly reduce ocular VEGF levels in a diabetic mouse model. | Samar Nassiri Gholamreza Houshmand Mostafa Feghhi Alireza Kheirollah Mohammad Bahadoram Nariman Nassiri | 2016 | International Journal of Ophthalmology(English edition)2016，9，6： | 3 |
| 20 | Artificial Neural Networks for Hardness Prediction of HAZ with Chemical Composition and Tensile Test of X70 Pipeline Steels显示文摘A neural network with feed-forward topology and back propagation algorithm was used to predict the effects of chemical composition and tensile test parameters on hardness of heat affected zone(HAZ)in X70 pipeline steels.The mass percent of chemical compositions(i.e.carbon equivalent based upon the International Institute of Welding equation(CEIIW),the carbon equivalent based upon the chemical portion of the Ito-Bessyo carbon equivalent equation(CEPcm),the sum of the niobium,vanadium and titanium concentrations(CVTiNb),the sum of the niobium and vanadium concentrations(CNbV),the sum of the chromium,molybdenum,nickel and copper concentrations(CCrMoNiCu)),yield strength(YS)at 0.005 offset,ultimate tensile strength(UTS)and percent elongation(El)were considered as input parameters to the network,while Vickers microhardness with 10 Nload was considered as its output.For the purpose of constructing this model,104 different data were gathered from the experimental results.Scatter diagrams and two statistical criteria,i.e.absolute fraction of variance(R2)and mean relative error(MRE),were used to evaluate the prediction performance of the developed model.The developed model can be further used in practical applications of alloy and thermo-mechanical schedule design in manufacturing process of pipeline steels. | Hesam POURALIAKBAR Mohammad-javad KHALAJ Mohsen NAZERFAKHARI Gholamreza KHALAJ | 2015 | Journal of Iron and Steel Research(International)2015，22，5： | 3 |
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