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Ultra-high extinction-ratio light modulation by electrically tunable metasurface using dual epsilon-near-zero resonances

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Opto-Electronic Advances 2021年第7期4卷 22-32页

作者： Arash nemati Qian Wang Norman Soo Seng Ang Weide Wang Minghui hong Jinghua Teng Institute of Materials Research and Engineering Agency for ScienceTechnology and Research(A*STAR)2 Fusionopolis WaySingapore 138634Singapore Department of Electrical and Computer Engineering National University of SingaporeEngineering Drive 3Singapore 117576Singapore

The lossy nature of indium tin oxide(ITO) at epsilon-near-zero(ENZ) wavelength is used to design an electrically tunable metasurface absorber. The metasurface unit cell is constructed of a circular resonator comprising two ITO discs and a high dielectric constant perovskite barium strontium titanate(BST) film. The ENZ wavelength in the accumulation and depletion layers of ITO discs is controlled by applying a single bias voltage. The coupling of magnetic dipole resonance with the ENZ wavelength inside the accumulation layer of ITO film causes total absorption of reflected light. The reflection amplitude can achieve ~84 d B or ~99.99% modulation depth in the operation wavelength of 820 nm at a bias voltage of-2.5 V. Moreover, the metasurface is insensitive to the polarization of the incident light due to the circular design of resonators and the symmetrical design of bias connections.

关键词： metasurface electrically tunable indium tin oxide(ITO) epsilon-near-zero(ENZ) barium strontium titanate(BST) polarization-insensitive

Specific serum immunoglobulin G to h pylori and CagA in healthy children and adults(south-east of Iran)

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World Journal of Gastroenterology 2007年第22期13卷 3117-3121页

作者： A Jafarzadeh MT Rezayati M nemati Department of Immunology Medical School Rafsanjan University of Medical Sciences Rafsanjan Iran

AIM: To evaluate the serologic IgG response to h pylori and CagA across age groups and in healthy children and adults. METhODS: Totally, 386 children aged 1-15 years and 200 adults aged 20-60 years, were enrolled to study. The serum samples of participant were tested for presence of anti-h pylori and anti-CagA IgG by using ELISA method. RESULTS: The seroprevalence of h pylori in adults was signif icantly higher than that observed in children (67.5/ vs 46.6/; P hildren, the seropositivity rate in males (51.9/) was signifi cantly (P higher than that observed in females (41.7/). The prevalence of serum anti-CagA antibody was 72.8/ and 67.4/ in infected children and adults, respectively. The mean titer of serum anti-CagA antibodies was significantly higher among children in comparison to adults (64.1 Uarb/mL vs 30.7; P hildren and adults the prevalence of serum anti-CagA antibody was higher in males compared to females (78.4/ vs 66.3/; P = 0.07 and 75.6/ vs 54.71/; P he age-specific prevalence of anti-h pylori and anti-CagA antibody (in infected subjects) was 37.6/ and 59.57/ at age 1-5 years, 46.9/ and 75/ at age 6-10 years, 54.9/ and 79.45/ at age 11-15, 59.01/ and 83.33/ at age 20-30 years, 66.6/ and 60.52/ at age 31-40 years, 73.46/ and 63.88/ at age 41-50 years and 75.75/ and 60/ at age 51-60 years with mean titer of anti-CagA antibody of 75.94, 63.32, 57.11, 52.06, 23.62, 21.52 and 21.80 Uarb/mL, respectively. There was significant difference between mean serum anti-CagA antibody in age subgroups (P hese results showed that anti-h pylori and anti-CagA antibodies were common in the children and adults. The h pylori-specifi c antibodies influenced by age and sex of subjects. Moreover, it seems that malesare more susceptible to infection with CagA+ strains compared to females. The seroprevalence of anti-CagA antibody was increased with age, up to 30 years and then decreased. It was also found that the magnitude of the IgG

关键词：伊朗幽门螺杆菌儿童成年人血清免疫球蛋白G 免疫保护力抗体

Microwave assisted synthesis & properties of nano hA-TCP biphasic calcium phosphate

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 441-445页

作者： E.Ghomash Pasand A.nemati M.Solati-hashjin K.Arzani A.Farzadi Department of Materials Engineering Science and Research BranchIslamic Azad UniversityTehran ***Iran Department of Biomedical Engineering Amirkabir University of TechnologyTehran 158754413Iran

Biphasic calcium phosphate （BCP） nanopowders were synthesized by using microwave and non-microwave irradiation assisted processes. The synthesized powders were pressed under a pressure of 90 MPa, and then were sintered at 1000-1200℃ for 1 h. The mechanical properties of the samples were investigated. The formed phases and microstructures were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The results showed that the synthesis time was shorter, along with a more homogeneous microstructure, when the microwave irradiation assisted method was applied. The compression strength and the Young＇s modulus of the samples synthesized with microwave irradiation were about 60 MPa and 3 GPa, but those of the samples synthesized without microwave irradiation were about 30 MPa and 2 GPa, respectively. XRD patterns of the microwave irradiation assisted and non-microwave irradiation assisted nanopowders showed the coexistence of hydroxyapatite （hA） and lricalcium phosphate （TCP） phases in the system.

关键词： bioceramics calcium phosphate hydroxyapatite （hA） Wicalcium phosphate nanoparticles （TCP） mechanical properties microwave irradiation

Multi Objective Load Shedding Framework

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Smart Grid and Renewable Energy 2015年第8期6卷 260-277页

作者： Atieh Delavari Milad nemati Mohammad h. Moradi Power System Engineering HamedanIran Photovoltaic Systems Power Engineering HamedanIran Microgrids Control Power Engineering HamedanIran

In this paper, a multi-objective load shedding framework on the power system is presented. The frame work is useable in any kind of smart power systems;the word of smart here refers to the availability of data transmission infrastructure (like PLC or power line carrier) in the system, in order to carry the system data to the load shedding framework. This is an open framework that means it can optimize load shedding problem by considering unlimited number of objective functions, in other word, the number of objectives can be as much as the operator decides, finally in the end of frame work just one matrix breaker state is chosen in a way of having the most compatibility with the operator ideas which are determined by objectives importance percentage which are one input groups of the framework. A two-stage methodology is used for the optimal load shedding problem. In the first stage, Discrete Multi-objective Particle Swarm Optimization method is used to find a collection of the best states of load shedding (Pareto front). In the second stage, the fuzzy logic is used as a Pareto front inference engine. Fuzzy selection algorithm (FSA) is designed in a way that it can infer according to the operator’s opinion without the expert interference that means rule base is formed automatically by fuzzy algorithm. FSA is consisted of two parts. Membership functions and rules base are formed automatically in the first part, the former in accordance with the costs of Pareto front particles and the latter in correspondence with importance percentage of objectives which are entered to FSA by operator;in other word, decision matrix is formed automatically in the algorithm according to the cost of Pareto front particles and importance percentage of objectives. In the Second part, Mamdani inference engine scrutinizes the Pareto front particles by the use of formed membership functions and rules base to know if they are compatible to operator’s opinion or not. Getting this approach, cost functions of each particle are considered as the

关键词： Objective Load Shedding Pareto Front Fuzzy

磺酸基修饰的纳米Fe_3O_4包覆二氧化硅颗粒作为可磁分离催化剂高效催化芳香醛与1,3-环二酮的Knoevenagel缩合反应和Michael加成反应(英文)

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催化学报 2012年第11期33卷 1825-1831页

作者： Firouzeh nemati Majid M.hERAVI Raheleh SAEEDI RAD Department of Chemistry Semnan UniversitySemnanIran Department of Chemistry School of ScienceAzzahra UniversityVanakTehranIran

Sulfonic acid-functionalized silica-coated nano-Fe3O4 particles(Fe3O4@SiO2-SO3h) have been prepared as a novel heterogeneous acid using a facile process.The material was subsequently identified as an efficient catalyst for the synthesis of a variety of tetraketone derivatives via the Knoevenagel condensation and Michael addition reactions of aromatic aldehydes to dimedone,1,3-indanedione,and 1,3-dimethyl barbituric acid.The catalyst could be readily recovered using a simple external magnet and reused several times without any significant loss in activity.The current catalytic process is both sustainable and economical because it operates under aqueous conditions,the catalyst can be recovered and reused,and the reactions themselves require only a short time and provide the products in high yield.

关键词： LFCO XRD 化学化学动力学

Relationship between pre-pubertal nutrition plane with reproduction performanceand milk quality in Kurdish female kids

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Asian pacific Journal of Reproduction 2017年第4期6卷 172-175页

作者： Sedigheh Menatian Mostafa nemati Mehdi Rashnavadi Ali Salimi Mohammad Rashid Taheri Farshad Yasemi Department of Animal Science Faculty of AgricultureIlam UniversityIlamIran Department of Veterinary Ilam UniversityIlamIran Department of Nomadic Management of Ilam Province IlamIran

Objective:To investigate the reproductive performance and milk quality to nutrition pre-pubertal plane in Kurdish female kids.Methods: Forty Kurdish female kids [aged (28.0±6.6) d and weighted (7.56±1.10) kg] were assigned randomly in pre-weaning period to one of two practical diets: low quality diet (LQD) [87 g CP/kg dray matter (DM) and 2.02 Mcal ME/kg DM], and high quality diet (hQD), (148 g CP/kg DM and 2.50 Mcal ME/kg DM). At weaning, from each group, one half of kids was separated randomly and allocated to LQD or hQD. Consequently, in post-weaning period, there were four treatment groups including: LQD pre and post-weaning (L-L), control group and LQD pre-weaning and hQD post-weaning (L-h);hQD pre-weaning and LQD post-weaning (h-L), hQD pre- and post-weanin (h-h). From 30 to 180 d of age, body weight and DM intake were determined every 2 wk.Results:Results showed that the hQD treatment enhanced body weight and DM intake during pre-weaning period, in comparison with the LQD treatment (Ph-h treatment had higher DM intake compared with other kid's treatments. Kids fed the hQD treatment had greater withers height compared to kids on the LQD treatment at 90 d of age (Phe L-h and h-h groups weighed more and were younger at puberty. In the period of pre-pubertal, diet plan was not significantly affected milk yield and reproductive performance at the first lactation.Conclusions:Overall, management strategies that have been used to availability of nutrition could increase growth and feed intake in Kurdish female kids. In addition, these strategic programs should be enhancing economic characteristics at the start of puberty of kid in goat husbandry.

关键词： Kids Iran Milk Nutrition Reproduction

Attitude Control of a Flexible Satellite by Using Robust Control Design Methods

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Intelligent Control and Automation 2013年第3期4卷 313-326页

作者： Reza Mohsenipour hossein nemati Mehrzad Nasirian Abdolreza Kashani Nia East Tehran (QiamDasht) Branch Islamic Azad University Tehran Iran Malekashtar University of Technology Tehran Iran

The increase of satellite’s dimensions has caused flexibility and formation of uncertainty in their model. This is because of space missions being more complex and using light moving structures in satellites. Satellites are also encountered with various circumferential disturbance torques. This uncertainty in model and disturbance torques will cause undesirable performance of satellites’ attitude control system. So, for attitude control of these satellites, those methods should be used which are robust to uncertainty of the plant’s model and can reject the effects of disturbances and the measurement noise. One of these methods is the robust control design method. But, because of pole’s place of these satellite’s dynamics equations, the designing procedure of robust control will face difficulties. In this paper, by using an internal feedback as a novel idea, the satellite’s dynamics equations are changed in such a way that the poles will be placed in proper locations. Then, for these new equations, by regarding the effects of flexibility as uncertainty and considering the uncertainty in inertia matrix of satellite, an h∞ controller has been designed and for better performance, a μ-controller has been improved. Afterwards, these two controllers are analyzed and compared for the original dynamic equations, not for the modified ones. Also, for comparison, a classic controller has been also designed for the original plant and eventually all these three controllers are compared with each other.

关键词： Attitude Control of Satellite Robust Control Flexible Satellite Uncertainty

Teaching reproductive endocrinology in Iran: Pilot assessment of hospital-based clinical modules for medical students at Tehran University of Medical Sciences

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health 2013年第2期5卷 175-178页

作者： Batool h. Rashidi Maryam nemati Mahya Ghazizadeh Shala A. Salem Gary S. Collins E. Scott Sills Centre for Statistics in Medicine Wolfson College Annexe University of Oxford Oxford UK Office for Reproductive Research Pacific Reproductive Center/PRC-Orange County Irvine USA Vali-e-Asr Reproductive health Research Center Tehran University of Medical Sciences Tehran Iran

This pilot study evaluated effectiveness and acceptance of a new hospital-based reproductive endocrinology curriculum among Iranian medical students. A voluntary, anonymous questionnaire was used to compare two teaching methods as applied to junior medical students at Tehran University of Medical Sciences. Students were randomly assigned to one of two clinical teaching settings;no student experienced both modules. Coursework for the pilot (experimental) group (n = 19) utilized a teaching approach comprising lectures, genetics laboratory, pelvic ultrasound, small group sessions, and opportunities to observe advanced reproductive technologies such as in vitro fertilization, ICSI, and embryo transfer. A control group (n = 34) received reproductive endocrinology instruction by the ‘traditional curriculum’, consisting mainly of lectures. Students were sampled at baseline and again atthe conclusion of their reproductive endocrinology session. Pre- and post-test data were analyzed for both groups;post-test differences between groups were also compared. No significant differences in mean age or gender mix were identified between the two study groups. Overall, the ques- tionnaire did not identify any significant intergroup differences for any parameter investigated. Although student acceptance rate appeared similar for both educational modules, the ratio of students having a “favorable regard” for reproductive medicine declined only among students randomized to the control group (41.2% vs. 32.3%). This report offers the first data on teaching reproductive endocrinology to medical students in Iran. Both traditional and innovative approaches to teaching reproductive endocrinology were well-accepted by students, although negative post-test responses were more common among students in the control group. While periodic quality assessments for existing clinical teaching methods are necessary, introduction of alternative teaching approaches is also important. Additional studies are planned to evaluate the impact this initiative

关键词： Medical Students Clinical Education Reproductive Endocrinology Iran

前后排列旋转圆柱体对流热交换的格子Boltzmann方法解

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应用数学和力学 2012年第4期33卷 406-424页

作者： h·内玛蒂 M·法哈第 K·赛迪戈亥 M·M·皮柔兹 N·N·阿巴塔瑞黄雅意张禄坤巴博尔工业大学机械工程学院伊朗巴博尔不详

用格子Boltzmann方法,数值研究流过前后排列两旋转圆柱体的二维层流.用二阶精度的速度场和温度场,数值化涉及运动的曲线边界.在Reynolds数为100,Prandtl数为0.71时,研究旋转速度比的变化和不同间距的影响.在4种不同间距(3,1.5,0.7,0.2)... 详细信息

用格子Boltzmann方法,数值研究流过前后排列两旋转圆柱体的二维层流.用二阶精度的速度场和温度场,数值化涉及运动的曲线边界.在Reynolds数为100,Prandtl数为0.71时,研究旋转速度比的变化和不同间距的影响.在4种不同间距(3,1.5,0.7,0.2)下,研究旋转速度比的不同范围.结果表明,当间距取大数值时,第1个圆柱体的升力和阻力系数,与单个圆柱体相类似;对所有间距(除间距3以外),第2个圆柱体的升力系数,随着角速度的增加而减小,而阻力系数反而增加.圆柱体表面平均周期Nusselt数的结果表明,当两圆柱体间距小且角速度又低时,热传导是主要的传热机理,而当间距大且角速度又高时,对流是主要的传热机理.

关键词：格子Boltzmann方法(LBM) 旋转圆柱体层流运动的曲线边界