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Alkali-metal-induced topological nodal line semimetal in layered XN2 （X=Cr, Mo, W）

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Frontiers of physics 2018年第5期13卷 87-95页

作者： Ali Ebrahimian mehrdad Dadsetani Department of Physics Lorestan University Khoramabad Iran

Based on first principles calculations and the K.p effective model, we propose that alkali metal depo- sition on the surface of hexagonal XN2 （X- Cr, Mo, W） nanosheets induces topologically nontrivial phases in these systems. When spin orbit coupling （SOC） is disregarded, the electron-like conduction band from N-pz orbitals can be considered to cross the hole-like valence band from X-d2z orbitals, thereby giving rise to a topological nodal line state in lithium-functionalized XN2 sheets （Li2MoN2 and Li2WN2）. Such band crossing is protected by the existence of mirror reflection and time reversal symmetry. More interestingly, the bands cross exactly at the Fermi level, and the linear dispersion regions of such band crossings extend to as high as 0.9 eV above the crossing. For Li2CrN2, the results reveal the emergence of a Dirac cone at the Fermi level. Our calculations show that lattice compression decreases the thickness of a Li2CrN2 nanosheet, leading to phase transition to a nodal line semimetal. The evolution of the band gap of Li2XN2 at the F point indicates that the nontrivial topological character of Li2XN2 nanolayers is stable over a large strain range. When SOC is included, the band crossing point is gapped out giving rise to quantum spin Hall states in Li2CrN2 nanosheets, while for Li2MoN2, the SOC-induced gap at the crossing points is negligible.

关键词： topological semimetal nodal-line states Dirac cone band inversion

Modeling optimal long-term investment strategies of hybrid wind-thermal companies in restructured power market

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1267-1279页

作者： Mohammad Tolou ASKARI Mohd.Zainal Abdin Ab.KADIR mehrdad TAHMASEBI Ehsan BOLANDIFAR Department of Electrical Engineering Semnan BranchIslamic Azad UniversitySemnanIran Centre for Electromagnetic and Lightning Protection Research(CELP) Faculty of EngineeringUniversiti Putra MalaysiaSerdangMalaysia Institute of Power Engineering(IPE) Universiti Tenaga NasionalKajangMalaysia Department of Electrical Power Engineering Eyvan-e-Gharb BranchIslamic Azad UniversityEyvanIran Department of Decision Sciences and Managerial Economics Chinese University of Hong KongHong KongChina

In this paper,a novel framework for the estimation of optimal investment strategies for combined wind-thermal companies is *** medium-term restructured power market was simulated by considering the stochastic and rational uncertainties,the wind uncertainty was evaluated based on a data mining technique,and the electricity demand and fuel price were simulated using the Monte Carlo *** Cournot game concept was used to determine the Nash equilibrium for each state and stage of the stochastic dynamic programming(DP).Furthermore,the long-term stochastic uncertainties were modeled based on the Markov chain *** longterm optimal investment strategies were then solved for combined wind-thermal investors based on the semi-definite programming(SDP)***,the proposed framework was implemented in the hypothetical restructured power market using the IEEE reliability test system(RTS).The conducted case study confirmed that this framework provides robust decisions and precise information about the restructured power market for combined wind-thermal investors.

关键词： Wind resources Power market Generation expansion planning Uncertainties Cournot game theory Stochastic dynamic programming

Experimental study of flow field distribution over a generic cranked double delta wing

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Chinese Journal of Aeronautics 2016年第5期29卷 1196-1204页

作者： Mojtaba Dehghan Manshadi Mehdi Eilbeigi Mohammad Kazem Sobhani mehrdad Bazaz Zadeh Mohammad Ali Vaziry Department of Mechanical and Aerospace Engineering Malek Ashtar University of Technology

The flow fields over a generic cranked double delta wing were investigated. Pressure and velocity distributions were obtained using a Pitot tube and a hot wire anemometer. Two different leading edge shapes, namely ＂sharp＂ and ＂round＂, were applied to the wing. The wing had two sweep angles of 55° and 30°. The experiments were conducted in a closed circuit wind tunnel at velocity 20 m/s and angles of attack of 5°- 20° with the step of 5°. The Reynolds number of the model was about 2 - 105 according to the root chord. A dual vortex structure was formed above the wing surface. A pressure drop occurred at the vortex core and the root mean square of the measured velocity increased at the core of the vortices, reflecting the instability of the flow in that region. The magnitude of power spectral density increased strongly in spanwise direction and had the maximum value at the vortex core. By increasing the angle of attack, the pressure drop increased and the vortices became wider; the vortices moved inboard along the wing, and away from the surface; the flow separation was initiated from the outer portion of the wing and developed to its inner part. The vortices of the wing of the sharp leading edge were stronger than those of the round one.

关键词： Cranked double delta wing Flow field Hot wire Leading edge shape Vortical flow

Lavender and dodder combined herbal syrup versus citalopram in major depressive disorder with anxious distress: A double-blind randomized trial

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Journal of Integrative Medicine 2020年第5期18卷 409-415页

作者： Toktam Sadat Firoozeei Majid Barekatain mehrdad Karimi Arman Zargaran Shahin Akhondzadeh Hossein Rezaeizadeh Deportment of Persion Medicine School of Persian MedicineTehron University of Medical SciencesTehran ***Iran Department of Psychiatry 5chool of Medicine.lsfahan University of Medical Sctences.Isfahan ***Iran Depertment of Trditioniod Phormay School of Persion Medicine.Tehran Untiversity of Medical Sciences.Tehran *** Iran Pschitric Research Center Roozbeh HospitalTehran University of Medical Sctences.Tehran ***Iran

Background: Major depressive disorder(MDD) accompanied by anxious distress is a chronic and disabling disorder. Its conventional drug therapies often have low patient compliance due to drug-related side effects. In Persian medicine, lavender-dodder syrup is one formula often recommended for such ***: This study compares the effects of lavender-dodder syrup to the standard drug, citalopram, for treating MDD with anxious ***, setting, participants and intervention: This six-week, double-blind, randomized, clinical trial was carried out in a psychiatric outpatient clinic. During the six-week intervention period, patients in citalopram group received citalopram tablets 20 mg/d plus 5 mL placebo syrup every 12 h;patients in group B received placebo tablets once daily plus 5 mL of lavender-dodder herbal syrup every 12 *** outcome measures: Primary outcome measures, depression and anxiety, were evaluated using the Hamilton Depression/Anxiety Rating Scales, and were scored at the beginning of the study and at weeks three and six. Secondary outcome measures including response to treatment and remission rates were also compared between the two ***: Fifty-six participants with MDD and anxious distress were randomly assigned to two *** depression scores significantly decreased in citalopram and herbal groups at weeks three and six(time effect: P < 0.001), although the observed changes were not significantly different between the groups(intervention effect: P = 0.61). Mean anxiety scores were not significantly different between the two groups at week three(P = 0.75). However, at the end of week six, the observed decrease was significantly higher in the herbal syrup group than the citalopram group(intervention effect: P = 0.007).Conclusion: The herbal syrup is an effective and tolerable supplement for treating MDD with anxious *** registration number: IRCT2016102430459 N1 on Iranian Registry of Clinical Trials.

关键词： Persian medicine Traditional medicine Anxiety Depression Phytotherapy Lavender Dodder Citalopram

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纯电动汽车车载电源性能在环测试平台研究

北京科技大学学报 2014年第10期36卷 1369-1377页

作者：李勇 mehrdad Kazerani 马飞北京科技大学机械工程学院北京100083 滑铁卢大学电气与计算机系

为研究纯电动汽车车载电源性能,提出并搭建了由异步电动机和直流电动机组成的在环测试平台.异步电动机用来模拟纯电动汽车的牵引电动机,直流电动机用来模拟汽车行驶时的阻力和惯量,对异步电动机和直流电动机分别实施转速控制和转矩控制... 详细信息

为研究纯电动汽车车载电源性能,提出并搭建了由异步电动机和直流电动机组成的在环测试平台.异步电动机用来模拟纯电动汽车的牵引电动机,直流电动机用来模拟汽车行驶时的阻力和惯量,对异步电动机和直流电动机分别实施转速控制和转矩控制.分析了电动汽车行驶工况,给出了简单循环工况下参考转速、转距和功率.设计了异步电动机调速系统转速控制器和电流控制器,建立了异步电动机调速系统的数学模型,提出了基于自适应模糊神经网络控制的异步电动机调速系统.仿真和实验结果表明,基于自适应模糊神经网络控制的调速系统明显优于PID控制的交流调速系统,在环测试平台能够较好跟踪参考转速和参考转距的变化.

关键词：电动汽车复合电源在环测试自适应模糊控制神经网络

HLA class Ⅱ alleles and risk for peripheral neuropathy in type 2 diabetes patients

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Neural Regeneration Research 2016年第11期11卷 1839-1844页

作者： Ahmad Marzban Javad Kiani mehrdad Hajilooi Hamzeh Rezaei Zohreh Kahramfar Ghasem Solgi Division of Endocrinology Department of Internal MedicineSchool of MedicineHamadan University of Medical Sciences Department of Immunology School of MedicineHamadan University of Medical Sciences Psoriasis Research Center Department of DermatologyFarshchian HospitalHamadan University of Medical Sciences

The potential impact of human leukocyte antigen （HLA） genotype variations on development of diabetic peripheral neuropathy （DPN） is not well determined. This study aimed to identify the association of HLA class II alleles with DPN in type 2 diabetes （T2D） patients. Totally 106 T2D patients, 49 with DPN and 57 without DPN, and 100 ethnic-matched healthy controls were analyzed. Both groups of the patients were matched based on sex, age, body mass index （BMI） and duration of T2D. Polyneuropathy was diagnosed using electrodiagnostic methods. HLA-DRB1 and DQB1 genotyping was performed in all subjects by the polymerase chain reaction with sequence-specific primers （PCR-SSP） method. T2D patients with DPN showed higher frequencies of HLA-DRB1＊10 and DRB1＊12 alleles compared to control group （P = 0.04）. HLA-DQB1＊02 allele and HLA-DRB1＊07-DQB1＊02 haplotype were associated with a decreased risk for developing DPN in T2D patients （P = 0.02 and P = 0.05 respectively）. Also, patients with severe neuropathy showed higher frequencies of DRB1＊07 （P = 0.003） and DQB1＊02 （P = 0.02） alleles than those with mild-to-moderate form of neuropathy. The distribution of DRB 1 and DQB 1 alleles and haplotypes were not statistically different between all patients and healthy controls. Our findings implicate a possible protective role of HLA-DQB1＊02 allele and HLA-DRB1＊07-DQB1＊02 haplotype against development of peripheral neuropathy in T2D patients. Therefore, variations in HLA genotypes might be used as genetic markers for prediction and potentially management of neuropathy in T2D patients.

关键词： nerve regeneration HLA-DRB1 HLA-DQB1 alleles genotypes haplotypes peripheral neuropathy type 2 diabetes neural regeneration

Is multi-hazard mapping effective in assessing natural hazards and integrated watershed management?

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Geoscience Frontiers 2020年第4期11卷 1203-1217页

作者： Hamid Reza Pourghasemi Amiya Gayen Mohsen Edalat mehrdad Zarafshar John P.Tiefenbacher Department of Natural Resources and Environmental Engineering College of AgricultureShiraz University71441-65186ShirazIran Department of Geography Ballygunge Science CollegeUniversity of CalcuttaKolkataWest Bengal700019India Crop Production and Plant Breeding Department School of AgricultureShiraz University71441-65186ShirazIran Natural Resources Department Fars Agricultural and Natural Resources Research and Education CenterAREEOShirazFarsIran Department of Geography Texas State UniversitySan MarcosTX78666USA

Natural hazards are often studied in ***,there is a great need to examine hazards holistically to better manage the complex of threats found in any *** regions of the world have complex hazard landscapes wherein risk from individual and/or multiple extreme events is *** parts of Iran experience a complex array of natural hazards-floods,earthquakes,landslides,forest fires,subsidence,and *** effectiveness of risk mitigation is in part a function of whether the complex of hazards can be collectively considered,visualized,and *** study develops and tests individual and collective multihazard risk maps for floods,landslides,and forest fires to visualize the spatial distribution of risk in Fars Province,southern *** do this,two well-known machine-learning algorithms-SVM and MARS-are used to predict the distribution of these *** floods,landslides,and forest fires were surveyed and *** locations of occurrence of these events(individually and collectively) were randomly separated into training(70%) and testing(30%) data *** conditioning factors(for floods,landslides,and forest fires) employed to model the risk distributions are aspect,elevation,drainage density,distance from faults,geology,LULC,profile curvature,annual mean rainfall,plan curvature,distance from man-made residential structures,distance from nearest river,distance from nearest road,slope gradient,soil types,mean annual temperature,and *** outputs of the two models were assessed using receiver-operating-characteristic(ROC) curves,true-skill statistics(TSS),and the correlation and deviance values from each models for each *** areas-under-the-curves(AUC) for the MARS model prediction were 76.0%,91.2%,and 90.1% for floods,landslides,and forest fires,***,the AUCs for the SVM model were 75.5%,89.0%,and 91.5%.The TSS reveals that the MARS model was better able to predict landslide risk,but was less able to

关键词： Multi-hazard risk mapping Considering flood Landside and forest fire jointly Machine-learning algorithms

Snow damages on trees of an uneven age in mixed broadleaf forests:effects of topographical conditions and tree characteristics

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Journal of Forestry Research 2019年第4期30卷 1383-1394页

作者： Farzam Tavankar Angela Lo Monaco mehrdad Nikooy Rachele Venanzi Amireslam Bonyad Rodolfo Picchio Department of Forestry Khalkhal BranchIslamic Azad UniversityKhalkhalIran Department of Agriculture and Forest Sciences(DAFNE) Tuscia UniversityVia S.Camillo de Lellis01100 ViterboItaly Department of Forestry Faculty of Natural ResourcesUniversity of GuilanSomehsaraIran

Snow damage on natural stands is an important problem concerning mountainous forest *** the present research,the frequency and intensity of heavy snow damage on natural stands and the relationship of damages with characteristics of trees,stand and topography were studied in mountainous forests of northern Iran.A systematic sampling design was applied to the study area(140 ha),with 122 circular *** grid dimension was100 m and each plot area was 1000 m^*** four types of snow damage to trees include:crown damage(8.6%),stem breakage(5.4%),uprooting(3.2%),and bending(1.4%).The frequency of crown damage grew with an increase inthe diameter at breast height(DBH),while the frequency of stem breakage,uprooting and bending decreased with an increase the *** frequency of crown damage,stem breakage,and total damages was related to tree species(p<0.01).Not all tree species were equally susceptible to snow *** amount of damage grew with increasing elevation and slope angle and decreased with increasing soil *** trees(DBH<25 cm)were more susceptible to snow damage than other *** damage decreased by as the trees in the stand became more mixed in *** susceptibility of trees to snow damage increased by height and slenderness *** adequate silvicultural operation,snow damage can be reduced to a minimum level in these natural forests.

关键词： Mixed forest Slenderness coefficient Snow damage Stem breakage Uprooting

Kinetic study of methane hydrate formation in the presence of carbon nanostructures

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Petroleum Science 2019年第3期16卷 657-668页

作者： Saeid Abedi-Farizhendi Mina Iranshahi Abolfazl Mohammadi mehrdad Manteghian Amir H. Mohammadi Faculty of Chemical Engineering Tarbiat Modares University Tehran Iran Department of Petroleum Engineering South Tehran Branch Islamic Azad University Tehran Iran Department of Chemical Engineering University of Bojnord Bojnord Iran Institut de Recherche en Genie Chimique et Petrolier (IRGCP) Paris Cedex France Discipline of Chemical Engineering School of Engineering University of KwaZulu-Natal Howard College Campus King George V Avenue Durban 4041 South Africa

The effect of synthesized nanostructures,including graphene oxide,chemically reduced graphene oxide with sodium dodecyl sulfate(SDS),chemically reduced graphene oxide with polyvinylpyrrolidone,and multi-walled carbon nanotubes,on the kinetics of methane hydrate formation was investigated in this *** experiments were carried out at a pressure of 4.5 MPa and a temperature of 0 ℃ in a batch *** adding nanostructures,the induction time decreases,and the shortest induction time appeares at certain concentrations of reduced graphene oxide with SDS and graphene oxide,that is,at a concentration of 360 ppm for reduced graphene oxide with SDS and 180 ppm for graphene oxide,with a 98% decrease in induction time compared to that in pure ***,utilization of carbon nanostructures increases the amount and the rate of methane consumed during the hydrate formation *** of multi-walled carbon nanotubes with a concentration of 90 ppm showes the highest amount of methane *** amount of methane consumption increases by 173% in comparison with that in pure *** addition of carbon nanostructures does not change the storage capacity of methane hydrate in the hydrate formation process,while the percentage of water conversion to hydrate in the presence of carbon nanotubes increases considerably,the greatest value of which occurres at a 90 ppm concentration of carbon nanotubes,that is,a 253% increase in the presence of carbon nanotubes compared to that of pure water.

关键词： Clathrate hydrate Kinetics Carbon nanostructures Graphene oxide SDS PVP