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Essential oil composition of two Scutellaria species from Iran

Journal of Traditional Chinese Medical Sciences 2019年第3期6卷 244-253页

作者： gharari zahra Bagheri Khadijeh Danafar Hossein Sharafi Ali Department of Plant Production and Genetics Faculty of AgricultureUniversity of ZanjanZanjanIran School of Pharmacy Zanjan University of Medical SciencesZanjanIran Zanjan Applied Pharmacology Research Center School of PharmacyZanjan University of Medical SciencesZanjanIran Zanjan Pharmaceutical Biotechnology Research Center Zanjan University of Medical SciencesZanjanIran

Objective:Medicinal plants Scutellaria multicaulis and Scutellaria bornmuelleri belong to the Scutellaria genus and Lamiaceae family,and are widely used in traditional Iranian *** study aims to characterize promising bioactive phytochemicals found in the aerial parts of *** and ***:Accordingly,volatile oils were obtained by hydrodistillation of *** and *** leaves and stems,and then analyzed by gas chromatographyemass spectrometry(GC/MS).Results:A total of 88 components,representing 92.4%of the oil(oil yield determined to be 0.53%,v/w),were identified in the essential oils of *** main group was sesquiterpene hydrocarbons(24%),with a-himachalene(7.2%),a-longipinene(6.8%),and a-copaene(3.2%)as the main components.A total of 89 chemicals,representing 83.2%of the essential oil(oil yield determined to be 0.31%,v/w),were detected in the essential oil of *** main components were steroids,such as 14-b-H-pregna(32.9%),hydrocarbons(22.5%),sesquiterpenes(11.4%),and monoterpenes(4.6%),which were considered minor *** contents of sesquiterpene and monoterpene hydrocarbons present in *** and *** were 24%and 7.1%,***,the contribution of oxygenated monoterpenes(4%)and sesquiterpenes(4.3%)in both species was less than 5%.Conclusion:As the first report on the chemical composition of *** and ***,this study showed that the major compounds were steroids and sesquiterpenes.

关键词： 14-b-H-Pregna GC/MS a-himachalene a-Longipinene Scutellaria

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3D Modeling and Determination of Factors Responsible for Zinc-Lead Mineralization in the Mehdiabad Deposit,Central Iran,based on Statistical Analysis of Geochemical Data

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 2040-2055页

作者： zahra BONYADI Department of Geology Faculty of SciencesImam Khomeini International UniversityQazvinIran

Although the Mehdiabad zinc-lead deposit is one of the most well-known deposits in the central Iran structural zone,the genesis of the deposit remains *** host rock of the ore is a dolomitic limestone of the Lower Cretaceous Taft *** the two main orebodies of the deposit,which includes the Black Hill and East Ridge ore zones,the oxide and sulfide ores are observed at the surface and at depth,*** elements Zn,Fe,Mn and Mg are more abundant in the East Ridge ore zone(in both sulfide and oxide ores),with Ba,Pb,Ag and Cu being more abundant in the Black Hill oxide *** on the distribution of elements and their correlation with each other in these ore zones,the elements are divided into three general groups,that of terrigenous elements,chemically-deposited elements and oreforming(hydrothermally deposited)elements,a division that is supported by the results of factor *** spatial distribution of elements is jointly affected by contact with host rocks,the boundary of oxide-sulfide ores and fault *** main factors governing the distribution of elements are the mechanical transfer of detrital sediments,chemical sedimentation,transfer by hydrothermal fluids,oxidation and surface dissolution,all of which affected the spatial distribution of *** ore-forming elements are mostly affected by hydrothermal fluids and *** study not only provides additional information about the genesis of the Mehdiabad deposit,but also could assist in the exploitation of ore and further exploration *** results of this study can aid in the exploration and exploitation of the Mehdiabad deposit and similar deposits in the region.

关键词： hydrothermal fluids geochemistry elemental distribution factor analysis Mehdiabad deposit MVT deposit

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Barrier-Certified Learning-Enabled Safe Control Design for Systems Operating in Uncertain Environments

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IEEE/CAA Journal of Automatica Sinica 2022年第3期9卷 437-449页

作者： zahra Marvi Bahare Kiumarsi IEEE Department of Electrical and Computer Engineering Michigan State UniversityMI 48824 USA

This paper presents learning-enabled barriercertified safe controllers for systems that operate in a shared environment for which multiple systems with uncertain dynamics and behaviors *** is,safety constraints are imposed by not only the ego system’s own physical limitations but also other systems operating *** the model of the external agent is required to impose control barrier functions(CBFs)as safety constraints,a safety-aware loss function is defined and minimized to learn the uncertain and unknown behavior of external *** specifically,the loss function is defined based on barrier function error,instead of the system model error,and is minimized for both current samples as well as past samples stored in the memory to assure a fast and generalizable learning algorithm for approximating the safe *** proposed model learning and CBF are then integrated together to form a learning-enabled zeroing CBF(L-ZCBF),which employs the approximated trajectory information of the external agents provided by the learned model but shrinks the safety boundary in case of an imminent safety violation using instantaneous sensory *** is shown that the proposed L-ZCBF assures the safety guarantees during learning and even in the face of inaccurate or simplified approximation of external agents,which is crucial in safety-critical applications in highly interactive *** efficacy of the proposed method is examined in a simulation of safe maneuver control of a vehicle in an urban area.

关键词： Control barrier functions(CBFs) experience replay learning safety-critical systems uncertainty

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A comprehensive layered approach for implementing internet of things-enabled smart grid:A survey

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Digital Communications and Networks 2022年第3期8卷 388-410页

作者： zahra Alavikia Maryam Shabro Electric Power Utility(EPU)Digital Transformation Center Niroo Research Institute(NRI)TehranIran

The current power grid confronts severe challenges in satisfying customers'*** transition to the much more flexible power grid enriched with renewable energies,micro-grid,and distributed energy resources has been considered as a straightforward solution to the customers’high *** smart equipment and renewable energies,electric power generation and storage through the power grid domains will be facilitated,which enables bi-directional energy and information *** power grid with such enhanced features is called Smart Grid(SG).Controlling and managing the diverse sets of variables in the SG requires precise measuring,monitoring,communicating,and analytic systems which increase the complexity of the *** complexity is the main barrier to the realization of the SG up to *** emergence of the Internet of Things(IoT)simplifies monitoring,communications,and data processing among smart things to connect to anything in the *** motivates the SG stakeholders and researchers to proceed with the best way to exploit the IoT technologies in the *** this survey paper,we summarize various efforts in this regard to highlight the advantages of the IoT-enabled SG and its probable *** this end,a comprehensive layered approach has been proposed in this paper to classify various applications of the IoT technologies in the *** IoT opportunities in each architecture layer facilitates the role of each technology and its relationship with other ***,open issues and future measures for the realization of IoT-enabled SG have been discussed in the paper.

关键词： Smart grid(SG) Internet of things(IoT) Layered approach Open issues

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Mode coupling in solar spicule oscillations

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Research in Astronomy and Astrophysics 2016年第1期16卷 145-150页

作者： zahra Fazel Astrophysics Department Physics FacultyUniversity of Tabriz

In a real medium which has oscillations, the perturbations can cause an energy transfer between different modes. A perturbation, which is interpreted as an interaction between the modes, is inferred to be mode coupling. The mode coupling process in an inhomogeneous medium such as solar spicules may lead to the coupling of kink waves to local Alfven waves. This coupling occurs in practically any conditions when there is smooth variation in density in the radial direction. This process is seen as the decay of transverse kink waves in the medium. To study the damping of kink waves due to mode coupling, a 2.5-dimensional numerical simulation of the initial wave is considered in spicules. The initial perturbation is assumed to be in a plane perpendicular to the spicule axis. The considered kink wave is a standing wave which shows an exponential damping in the inhomogeneous layer after the mode coupling occurs.

关键词： solar spicules -- mode coupling -- MHD waves

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Electronic properties and topological phases of ThXY(X= Pb, Au, Pt and Y= Sb, Bi, Sn) compounds

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Chinese Physics B 2016年第3期25卷 319-324页

作者： zahra Nourbakhsh Aminollah Vaez Physics Department Faculty of Science University of Isfahan

The electronic properties and topological phases of ThXY （X = Pb, Au, Pt, Pd and Y = Sb, Bi, Sn） compounds in the presence of spin-orbit coupling, using density functional theory are investigated. The ThPtSn compound is stable in the ferromagnetic phase and the other ThXY compounds are stable in nonmagnetic phases. Band structures of these compounds in topological phases （insulator or metal） and normal phases within generalized gradient approximation （GGA） and Engel- Vosko generalized gradient approximation （GGA_EV） are compared. The ThPtSn, ThPtBi, ThPtSb, ThPdBi, and ThAuBi compounds have topological phases and the other ThXY compounds have normal phases. Band inversion strengths and topological phases of these compounds at different pressure are studied. It is seen that the band inversion strengths of these compounds are sensitive to pressure and for each compound a second-order polynomial fitted on the band inversion strengths-pressure curves.

关键词： topological phase density functional theory energy band gap band inversion strength

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Ba promoter effect on cobalt-catalyzed ammonia decomposition kinetics: A theoretical analysis

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Journal of Energy Chemistry 2024年第12期99卷 182-192页

作者： zahra Almisbaa Philippe Sautet Department of Chemical and Biomolecular Engineering University of CaliforniaLos AngelesCA 90095United States Department of Chemistry and Biochemistry University of CaliforniaLos AngelesCA 90095United States

Ammonia decomposition is a key reaction in the context of hydrogen storage, transport, and release. This study combines density functional theory(DFT) calculations with microkinetic modeling to address the promotion mechanism of Ba species for ammonia decomposition on Co catalysts. The modified adsorption properties of Co upon the addition of metallic Ba or BaO suggest that the promoters play a role in alleviating the competitive adsorption of H. Calculating the full reaction pathway of ammonia decomposition shows that limiting the investigation to the N–N association step, as done previously, overlooks the effect of the promoter on the energy barriers of the NHxdehydrogenation steps. Challenges of modeling the ammonia decomposition reaction are addressed by understanding that the NH_(2) intermediate is stabilized on the step sites rather than the terrace sites. When the effect of H-coverage on the adsorption of NH_(3) is not considered in the microkinetic simulations, the results conflict with the ***, accounting for the effect of H-coverage, as performed here, shows that BaO-doped Co has higher rates than pristine Co and Ba-doped Co at the reaction temperature of 723.15 K. When H is adsorbed on the Ba-doped Co, the adsorption of ammonia becomes significantly endergonic, which makes the rates relatively slow. The superiority of the BaO-promoted catalyst is attributed to a lower energy for the transition state of the rate-determining step, coupled with a reduced impact of the hydrogen coverage on weakening the ammonia adsorption. The kinetic analysis of the influence of Ba and BaO on the Co surface shows that BaO-doped Co aligns more closely with experimental observations than Badoped Co. This implies that Ba on the Co surface is likely to be in an oxide form under reaction *** the kinetics of the ammonia decomposition reaction provides a foundation for developing highly effective catalysts to accelerate the industrial utilizatio

关键词： Cobalt catalyst Ammonia decomposition Hydrogen carrier DFT Microkinetic

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Tight-binding study of quantum transport in nanoscale GaAs Schottky MOSFET

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Chinese Physics B 2013年第9期22卷 634-639页

作者： zahra Ahangari Morteza Fathipour Department of Electrical Engineering Science and Research BranchIslamic Azad University School of Electrical and Computer Engineering University of Tehran

This paper explores the band structure effect to elucidate the feasibility of an ultra-scaled GaAs Schottky MOSFET （SBFET） in a nanoscale regime. We have employed a 20-band sp3dSs＊ tight-binding （TB） approach to compute E - K dis- persion. The considerable difference between the extracted effective masses from the TB approach and bulk values implies that quantum confinement affects the device performance. Beside high injection velocity, the ultra-scaled GaAs SBFET suffers from a low conduction band DOS in the F valley that results in serious degradation of the gate capacitance. Quan- tum confinement also results in an increment of the effective Schottky barrier height （SBH）. Enhanced Schottky barriers form a double barrier potential well along the channel that leads to resonant tunneling and alters the normal operation of the SBFET. Major factors that may lead to resonant tunneling are investigated. Resonant tunneling occurs at low temperatures and low drain voltages, and gradually diminishes as the channel thickness and the gate length scale down. Accordingly, the GaAs （100） SBFET has poor ballistic performance in nanoscale regime.

关键词： band structure quantum confinement effects resonant tunneling Schottky MOSFET

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Comparative Study of Entanglement and Wigner Function for Multi-Qubit GHZ-Squeezed State

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Communications in Theoretical Physics 2017年第12期67卷 729-734页

作者： Fatima-zahra Siyouri Laboratoire de Physique Thèorique Département de Physique Faculté des Sciences Université Mohammed Ⅴ-Agdal

In this paper we address the possibility of using the Wigner function to capture the quantum entanglement present in a multi-qubit system. For that purpose, we calculate both the degree of entanglement and the Wigner function for mixed tripartite squeezed states of Greenberger–Horne–Zeilinger(GHZ) type then we compare their behaviors. We show that the role of Wigner function in detecting and quantifying bipartite quantum correlation [Int. J. Mod. Phys. B30(2016) 1650187] may be generalized to the multipartite case.

关键词： negativity of Wigner function entanglement squeezed states tripartite GHZ non-classicality

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A New Anti-counterfeiting Feature Relying on Invisible Non-toxic Fluorescent Carbon Dots

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Journal of Analysis and Testing 2020年第4期4卷 307-315页

作者： zahra Fatahi Neda Esfandiari zahra Ranjbar Protein Research Center Shahid Beheshti University*** TehranIran Faculty of Life Sciences and Biotechnology Shahid Beheshti University*** TehranIran Faculty of Surface Coatings and Novel Technologies Institute for Color Science and Technology(ICST)*** TehranIran

Fluorescent patterning has attracted a great deal of attention owing to its potential applications in different areas in particular anti-counterfeiting *** carbon dots(CDs)as a type of fluorescent dyes can be used in invisible patterning due to their remarkable optical *** study attempts to introduce green fluorescent CDs as a promising factor in textile ***,a new green source opted to prepare CDs using the hydrothermal ***,toxicity assays were performed to prove the safety of these carbon-based nanoparticles for *** were also conjugated with cotton fiber ***,these green prepared CDs are promising for security labeling in the textile industry.

关键词： Green carbon dots Cytotoxicity Anti-counterfeiting Cotton fiber

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