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Chinese Chemical Letters 2010年第12期21卷 1419-1422页

作者： Hooshang Vahedi Ghadir Rajabzadeh Fahimeh Farvandi Department of Chemistry Payame Noor University(PNU)MashhadIran Khorasan Research Institute for Food Science and Technology Iran

4-Amino-3-mercapto-6-methyl-l,2,4-triazin-5（4H）-one 1 converted to 4-amino-6-methy-3-（methylthio）-1,2,4-triazin-5（4H）-one by methylation with methyl *** hydrazination of the resulting compound afforded 4-amino-3-hydrazinyl-6- methyl-l,2,4-triazin-5（4H）-one 2 as a building block,to the synthesis of some novel derivatives of[1,2,4]triazino- [4,3,b][1,2,4,5]tetrazepine 3-6,by the reaction with 3-chloropentane-2,4-dione,chloro acetonitrile,1,3-dichloroacetone,and methyl *** general synthetic procedure can be extended to the preparation of wide variety of tetrazepines using 1,2- bielectrophiles derivatives.

关键词： 4-Amino-3-hydrazinyl-6-methyl-1,2,4-triazin-5(4H)-one Triazino[4,3,b]tetrazepine 3-Chloropentane-2,4-dione Chloro acetonitrile 1,3-Dichloroacetone Methyl bromoacetate

Interfacial synthesis and properties of L-lysine-derived optically active poly(ester-imide)s

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Chinese Chemical Letters 2011年第5期22卷 607-610页

作者： Saeed Zahmatkesh Ali Reza Alborzi Javad Sadeghi Karim Zare Department of Science Payame Noor University(PNU)TehranIran Department of Chemistry Islamic Azad university FirouzabadFarsIran

L-Lysine hydrochloride was transformed to ethyl L-lysine *** salt was reacted with trimellitic anhydride to yield the corresponding diacid（1）.Intertacial polycondensation results novel poly（ester-imide）s（PEI_（a-i））.These polymers have inherent viscosities in the range of 0.23-0.47 dl g^（-1）,display optical activity,and are readily soluble in polar aprotic *** start to decompose（T_（10%）） above 350℃and display glass-transition temperatures at 100.42-172.81℃.All of the above polymers were fully characterized by UV,FT-IR and ~1H NMR spectroscopy,elemental analysis,TGA,DSC,inherent viscosity measurement and specific rotation.

关键词： Chiral Optically active L-Lysine Poly(ester-imide) Interfacial polymerization

Evolving Hoava cosmological horizons

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Chinese Physics C 2016年第9期40卷 63-74页

作者： Mohsen Fathi Morteza Mohseni Department of Physics Payame Noor University(PNU)P.O.Box 19395—3697 TehranI R.of Iran

Several sets of radially propagating null congruence generators are exploited in order to form 3-dimensional marginally trapped surfaces, referred to as black hole and cosmological apparent horizons in a Hoava universe. Based on this method, we deal with the characteristics of the 2-dimensional space-like spheres of symmetry and the peculiarities of having trapping horizons. Moreover, we apply this method in standard expanding and contracting FLRW cosmological models of a Horava universe to investigate the conditions under which the extra parameters of the theory may lead to trapped/anti-trapped surfaces both in the future and in the past. We also include the cases of negative time, referred to as the finite past, and discuss the formation of anti-trapped surfaces inside the cosmological apparent horizons.

关键词： Horava universe standard cosmology null congruence expansion black hole horizons white holes

Stripping voltammetric determination of Cd(Ⅱ)based on multiwalled carbon nanotube functionalized with 1-(2-pyridylazo)-2-naphthol

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Chinese Chemical Letters 2011年第12期22卷 1469-1472页

作者： Alireza Mohadesi Hadi Beitollahi Mohammad Ali Karimi Department of Chemistry Payame Noor UniversityTehran 19395-4697Iran Department of Chemistry Payame Noor University(PNU)P.O.Box 76175-559KermanIran Environmental Department Research Institute of Environmental SciencesInternational Center for SciencesHigh Technology and Environmental SciencesKermanIran Department of Chemistry & Nanoscience and Nanotechnology Research Laboratory(NNRL) Payame Noor University(PNU)SirjanIran

The present work has focused on the modification of multiwalled carbon nanotube with a ligand,l-（2-pyridylazo）-2-naphthol, and its potential application for the development of a new,simple and selective modified glassy carbon electrode for stripping voltammetric determination of Cd（Ⅱ）.The analytical curve for Cd（Ⅱ） ions covered the linear range varying from 0.8 up to 220.4μgL^（-1）.The limit of detection was found to be 0.1μgL^（-1）,while the relative standard deviation（RSD） at 50.0μgL^（-1） was 1.8%（n=5）.This modified electrode was successfully applied for determination of Cd（Ⅱ） in some water samples.

关键词： Multiwalled carbon nanotube 1-(2-Pyridylazo)-2-naphthol Cadmium(Ⅱ) Stripping voltammetry

Signal promoting role of a p-type transition metal dichalcogenide used for the detection of ultra-trace amounts of diclofenac via a labeled aptasensor

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Frontiers of Chemical Science and Engineering 2019年第4期13卷 823-831页

作者： Abdolhamid Hatefi-Mehrjardi Amirkhosro Beheshti-Marnani Zarrin Es'haghi Department of Chemisttry Payamc Noor University(PNU)TehranIran

A p-type transition metal dichalcogenide(WS2)was synthesized and hybridized with graphene oxide via a simple hydrothermal *** as-prepared material was used to modify a glassy carbon electrode for the fabrication of a simple,stable,and repeatable methylene blue-labeled“signal-off”aptasensor used for the sensitive determination of very low amounts of sodium diclofenac(DCF).The synthetic material,modification process,and role of WS2 in the current response enhancement were studied by X-ray diffraction,energy-dispersive X-ray spectroscopy,field emission scanning electron microscopy,high resolution transmission electron microscopy,Hall effect,cyclic voltammetry,differential pulse voltammetry,and electrochemical impedance ***,a wide linear range of DCF concentration(0.5-300 nmol/L),very low limit of detection(0.23 nmol/L),and good selectivity were obtained using the differential pulse voltammetry method with the assembled ***,the fabricated aptasensor was successfully developed for physiological real samples with significant recoveries.

关键词： labeled aptasensor transition metal dichalcogenide graphene oxide sodium diclofenac

Physiological responses of Brassica napus to fulvic acid under water stress: Chlorophyll a fluorescence and antioxidant enzyme activity

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The Crop Journal 2015年第5期3卷 434-439页

作者： Ramin Lotfi Mohammad Pessarakli Puriya Gharavi-Kouchebagh Hossein Khoshvaghti Department of Plant Eco-physiology Faculty of Agriculture University of Tabriz School of Plant Science The University of Arizona Department of Agriculture Payame Noor University (PNU)

The ameliorative effect of fulvic acid(0, 300, and 600 mg L-1) on photosystem II and antioxidant enzyme activity of the rapeseed(Brassica napus L.) plant under water stress(60, 100, and 140 mm evaporation from class A pan) was studied using split plots in a randomized complete block design with three replications. Results indicated that application of fulvic acid(FA) improved the maximum quantum efficiency of PSII(Fv/Fm)and performance index(PI) of plants under both well-watered and limited-water conditions. The time span from Foto Fmand the energy necessary for the closure of all reaction centers was significantly increased, but the size of the plastoquinone pool was reduced with increasing water stress levels. Plants treated with FA had higher peroxidase and catalase activities under all irrigation conditions. Activities of ascorbate peroxidase and superoxide dismutase in plants increased with increasing water stress. Malondialdehyde increased under severe water stress, but application of FA significantly decreased lipid peroxidation. Production of reactive oxygen species(ROS) is a common phenomenon in plants under stress. Under this condition, the balance between the production of ROS and the quenching activity of antioxidants is upset, often resulting in oxidative damage. In this study, application of FA significantly increased fluorescence of chlorophyll a, inhibiting ROS production and enhancing antioxidant enzymes activity that destroyed ROS. Thus, ROS in plant cells was reduced under water stress by application of FA and consequently lipid peroxidation was reduced.

关键词： Brassica napus Fluorescence Antioxidant enzyme Wat

EXPERIMENTAL AND THEORETICAL INVESTIGATION OF THE FIRST FOLD CREATION IN THIN WALLED COLUMNS

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Acta Mechanica Solida Sinica 2010年第4期23卷 353-360页

作者： Abbas Niknejad G.H.Liaghat H.Moslemi Naeini A.H.Behravesh Mechanical Engineering Department Yasouj University Faculty of Engineering Payame Noor University (PNU) Mechanical Engineering Department Faculty of EngineeringTarbiat Modares University

In this paper, a theoretical formula is presented to predict the instantaneous folding force of the first fold creation in square and rectangular columns under axial *** rectangular column is a small and single model of honeycombs with square or rectangular *** are based on the analysis of the Basic Folding Mechanism （BFM）.For this purpose, sum of the dissipated energy rate under bending around horizontal and inclined hinge lines and the dissipated energy rate under extensional deformations was equal to the work rate of the external force on the *** final formula obtained in this research, reasonably predicts the instantaneous folding force of single-cell square and rectangular honeycombs instead of the average ***, according to the calculated theoretical relation, the instantaneous folding force of the first fold creation in a square column was sketched versus folding distance and compared to the experimental results, which showed a good correlation.

关键词： dissipated energy rate first fold creation instantaneous folding force thin walled column

New tetrazole-based organic dyes for dye-sensitized solar cells

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Journal of Energy Chemistry 2015年第6期24卷 770-778页

作者： Zahra Jafari Chermahini Alireza Najafi Chermahini Hossein A Dabbagh Abbas Teimouri Department of Chemistry Isfahan University of Technology Chemistry Department Payame Noor University (PNU)

A series of new metal-free organic dyes that contain donors with triphenylamine or its derivatives and tetrazole-based acceptors were synthesized and characterized by photophysical, electrochemical, and the- oretical computational methods. They were applied in nanocrystalline TiO2 solar cells （DSSCs）. It is found that the introduction of diphenylamine units as antennas in the as-synthesized dyes could improve photo- voltaic performance compared with phenothiazine and carbazole units as antennas in DSSCs. The dye with （2H-tetrazol-5-yl） acrylonitrile electron acceptor also displayed the highest solar-to-electrical energy conver- sion efficiency.

关键词： Tetrazole Dye sensitized solar cells DFT Synthesis Anchoring group

Application of a simple calorimetric data analysis on the binding study of cyanide ions by Jack bean urease

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Chinese Chemical Letters 2010年第4期21卷 457-460页

作者： G.Rezaei Behbehani A.A.Saboury M.Mohebbian S.Ghammamy Chemistry Department Imam Khomeini International UniversityQazvinIran Institute of Biochemistry and Biophysics University of TehranTehranIran Chemistry Department Payame Noor University(PNU)AbharIran

Cyanide ion was studied as an effector of Jack bean urease(JBU) at 300 K in 30 mmol/LTris buffer,pH 7 by isothermal titration calorimetry(ITC).The simple novel model was used for CN^- + JBU interaction over the whole range of CN^- *** binding parameters recovered from the simple novel model were attributed to the cyanide ion *** was found that cyanide ion acted as a noncooperative inhibitor of JBU,and there is a set of 12 identical and independent binding sites for CN^- *** di...

关键词： Isothermal titration calorimetry Cyanide ion Jack bean urease Binding parameter

Thermodynamic study of CN^- ion inhibition of Jack bean urease using the extended solvation theory

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Chinese Chemical Letters 2009年第11期20卷 1389-1392页

作者： G.Rezaei Behbehani A.A.Saboury M.Mohebbian S.Tahmasbi Sarvestani M.Poorheravi Chemistry Department Imam Khomeini International UniversityQazvinIran Institute of Biochemistry and Biophysics University of TehranTehranIran Chemistry Department Payame Noor University(PNU)AbharIran

Cyanide ion was studied as an inhibitor of Jack bean urease at 300 K in 30 mmol/L tris buffer, pH 7. The inhibition was investigated by isothermal titration calorimetry （ITC）. The extended solvation model was used for CN^- ＋ JBU interaction over the whole range of CN^- concentrations. The binding parameters recovered from the solvation model were attributed to the cyanide ion interaction. It was found that cyanide ion acted as a non-cooperative inhibitor ofurease, and there is a set of 12 ± 0.12 identical and independent binding sites for CN- ions. The dissociation equilibrium constant is 749.99 umol/L. The molar enthalpy of binding is AH= -13.60 kJ mol^-1.

关键词： Jack bean urease Cyanide ion Isothermal titration calorimetry Binding parameters Inhibitor