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Chinese Journal of Polymer Science 2013年第7期31卷 1002-1010页

作者： mohammad ali karimi Zarchi Saeed Barani Department of Chemistry College of SciencesYazd University

In this article a rapid and facile method for synthesis of acyl azide is described. The cross-linked poly（N-methyl-4- vinylpyridinium） azide ion, [Pa-VP]N3 is prepared and used as an efficient polymeric reagent for synthesis of acyl azides from acyl halides at room temperature under heterogeneous conditions. Various benzoyl halides, with electron-withdrawing groups as well as electron-donating groups, were transformed into the corresponding benzoyl azides in high to excellent yields in short reaction times. The acyl azide products were characterized by FT-IR, and some of them were also characterized by IH- and/or 13C-NMR spectroscopy, and physical properties were compared to literature values of known compounds. The spent polymeric reagents can be regenerated and reused for several times without losing their activity. Relative to the reported methods, the present method has the advantages of operational simplicity, mild reaction conditions, fast reaction rates, simple reaction work-up and lower hazardous and potentially explosive nature. Also the present method is the first procedure for the synthesis of acyl azides from acyl halides by using a polymer-supported azide ion under heterogeneous conditions.

关键词： Acyl azide Acyl halide Polymeric reagent Heterogeneous condition.

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

Electrocatalytic oxidation of hydrazine with alizarin red S as a homogenous mediator on the glassy carbon electrode

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Science China Chemistry 2010年第5期53卷 1194-1200页

作者： mohammad Mazloum-Ardakani Roya Mazidi mohammad Hossein Mashhadizadeh Parvanah Rahimi mohammad ali karimi Department of Chemistry Faculty of ScienceYazd University Department of Chemistry Payam Noor UniversityArdakan Center Department of Chemistry Faculty of ScienceTarbiat Moalem University Department of Chemistry Faculty of SciencePayam Noor UniversitySirjan Center

Electro-catalytic oxidation and detection of hydrazine on a glassy carbon electrode,at pH 6.0,was studied by using alizarin red S as a homogeneous *** overall number of electrons involved in the catalytic oxidation of hydrazine and that involved in the rate-determining step were four and one,*** interfering effect of some cations,anions and organic compounds were *** current for this process varied linearly with the square root of the scan *** kinetic parameters,such as the electron transfer coefficient(α) and catalytic rate constant(k) ,were determined using cyclic voltammetry,linear sweep voltammetry and *** electro-catalytic response was optimized with regards to the pH,scan rate,hydrazine concentration and other variables.

关键词： alizarin red S hydrazine glassy carbon electrode electro-catalytic oxidation voltammetry

Microstructural and mechanical properties assessment of transient liquid phase bonding of CoCuFeMnNi high entropy alloy

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Transactions of Nonferrous Metals Society of China 2021年第10期31卷 3063-3074页

作者： mohammad ali karimi Morteza SHAMANIAN mohammad Hossein ENAYATI Department of Materials Engineering Isfahan University of TechnologyIsfahan 84156-83111Iran

The transient liquid phase(TLP)bonding of CoCuFeMnNi high entropy alloy(HEA)was *** TLP bonding was performed using AWS BNi-2 interlayer at 1050℃ with the TLP bonding time of 20,60,180 and 240 *** effect of bonding time on the joint microstructure was characterized by SEM and *** results confirmed that complete isothermal solidification occurred approximately at 240 min of bonding *** samples bonded at 20,60 and 180 min,athermal solidification zone was formed in the bonding area which included Cr-rich boride and Mn3Si intermetallic *** all samples,theγsolid solution was formed in the isothermal solidification zone of the bonding *** evaluate the effect of TLP bonding time on mechanical properties of joints,the shear strength and micro-hardness of joints were *** results indicated a decrement of micro-hardness in the bonding zone and an increment of micro-hardness in the adjacent zone of *** minimum and maximum values of shear strength were 100 and 180 MPa for joints with the bonding time of 20 and 240 min,respectively.

关键词： high entropy alloy CoCuFeMnNi alloy transient liquid phase bonding bonding time solid solution isothermal solidification microstructure mechanical properties

Effect of Gd3+-,Pr3+-or Sm3+-substituted cobalt-zinc ferrite on photodegradation of methyl orange and cytotoxicity tests

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Journal of Rare Earths 2019年第12期37卷 1288-1295页

作者： Seyed Mahdi Peymani-Motlagh Nadia Moeinian Mojtaba Rostami Mahdi Fasihi-Ramandi ali Sobhani-Nasab Mehdi Rahimi-Nasrabadi mohammad Eghbali-Arani mohammad Reza Ganjali Teofil Jesionowski Hermann Ehrlich mohammad ali karimi Narges Ajami Department of Chemistry Imam Hossein UniversityTehran 16765-3454Iran Department of Chemistry Payame Noor UniversityTehran 19395-4697Iran Young Researchers and Elite Club Karaj BranchIslamic Azad UniversityKaraj ***Iran Molecular Biology Research Center Systems Biology and Poisoning InstituteBaqiyatallah University of Medical SciencesTehran ***Iran Social Determinants of Health(SDH)Research Center Kashan University of Medical SciencesKashan ***Iran Core Research Lab Kashan University of Medical SciencesKashan ***Iran Faculty of Pharmacy Baqiyatallah University of Medical SciencesTehran 195163759Iran Department of Physics University of KashanKashan ***Iran Center of Excellence in Electrochemistry Faculty of ChemistryUniversity of TehranTehran ***Iran Institute of Chemical Technology and Engineering Faculty of Chemical TechnologyPoznan University of TechnologyPoznan 60965Poland Institute of Electronic and Sensor Materials TU Bergakademie FreibergFreiberg 09599Germany

Gd3+-,Pr3+-or Sm3+-doped Co-Zn(Co0.5Zn0.5Fe2 O4)magnetic ferrites(i.e.,Co0.5Zn0.5Gd0.1Fe1.9O4,Co0.5Zn0.5Pr0.1Fe1.9O4 and Co0.5Zn0.5Sm0.1Fe1.9O4)were prepared using a facile sol-gel approach,and the structure,surface morphology and chemical composition of the products were studied by means of scanning electron microscopy(SEM),energy dispersive X-ray analysis(EDX),X-ray diffraction(XRD),UVvisible diffuse reflectance spectroscopy(DRS),photoluminescence(PL)spectroscopy,Fourier transform infrared spectroscopy(FT-IR)and vibrating sample magnetometer(VSM)*** patterns show the Co-Zn product is composed of cubic spinel phases with few impurities or secondary phases,and the average crystallite sizes of the samples are determined to be approximately^51—80,~99—181,~68—103 and^83—133 *** the coercivity and remnant and saturation magnetizations,evaluated by vibrating sample magnetometer(VSM),are found to increase linearly with the incorporation of Gd3+,Pr3+and Sm3+in the product *** CO1-xZnxFe2-yRyO4 photocatalyst sample is found to display a red shift in its absorption,and exhibits outstanding photocatalytic effects in the degradation of MO under ultraviolet(UV)*** is attributed to the reduction of the band gap of cobalt-zinc ferrite due to the presence of rare earth *** in vitro evaluations of the cytotoxic effects of the synthesized nanoparticles were performed on a HeLa cell line.

关键词： Magnetic ferrite Rare earth ions Photocatalyst Cytotoxicity Sol-gel

Leontiasis Ossea Following Secondary Hyperparathyroidism and Hemodialysis

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Journal of Biosciences and Medicines 2015年第7期3卷 54-59页

作者： Pooneh Dehghan ali Zahiri mohammad ali karimi mohammad Hossein Ghadiani Department of Radiology Taleghani Hospital Shahid Beheshti Medical University Tehran Iran Department of Nephrology Taleghani hospital Shahid Beheshti Medical University Tehran Iran

Leontiasis ossea is a rare medical condition which is characterized by an overgrowth of the facial and cranial bones secondary to chronic renal failure and secondary hyperparathyroidism. We reported a case of leontiasis ossea with history of secondary hyperparathyroidism due to end-stage renal disease on regular hemodialysis. A 37-year-old female with end-stage renal disease from lupus disease on regular hemodialysis complaining of progressive facial deformity for two years causing dyspnea, dental malocclusion and dysarthria with the final diagnosis of uremic leontiasis ossea. It is important to recognize features of leontiasis ossea, as it may result in life-threatening upper airway obstruction and compressive cranial neuropathy while after parathyroidectomy, facial changes can be stabilized or improved mildly.

关键词： Hyperparathyroidism Hemodialysis Leontiasis Ossea

Application of H-Point Standard Addition Method and Multivariate Calibration Methods to the Simultaneous Kinetic-Potentiometric Determination of Cerium(IV) and Dichoromate

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American Journal of Analytical Chemistry 2010年第2期1卷 73-82页

作者： mohammad ali karimi mohammad Hossein Mashhadizadeh mohammad Mazloum-Ardakani Fatemeh Rahavian Department of Chemistry & Nanoscience and Nanotechnology Research Laboratory (NNRL) Faculty of Sciences Payame Noor University (PNU) Department of Chemistry Faculty of Sciences Payame Noor University (PNU) Department of Chemistry Tarbiat Moallem Un

A kinetic-potentiometric method for simultaneous determination of Cerium(IV) and dichoromate (Cr2O72-) by H-point standard addition method (HPSAM), partial least squares (PLS) and principal component regression (PCR) using fluoride ion-selective electrode (FISE) is described. In this work, the difference between the rate of the oxidation reaction of Fe(II) to Fe(III) in the presence of Ce4+ and Cr2O72- is based of the method. The rate of consume fluoride ion for making complex is detected with a FISE. The results show that simultaneous determination of Ce4+ and Cr2O72- can be done in their concentration ranges of 1.0-30.0 and 0.1-20.0 μg/mL, respectively. The total relative standard error for applying the PLS and PCR methods on 8 synthetic samples was 2.97 and 3.19, respectively in the concentration ranges of 1.0-30.0 μg/mL of Ce4+ and 0.1-20.0 μg/mL of Cr2O72-. In order for the selectivity of the method to be assessed, we evaluated the effects of certain foreign ions upon the reaction rate and assessed the selectivity of the method. The proposed methods (HPSAM, PLS and PCR) were evaluated using a set of synthetic sample mixtures and then applied for simultaneous determination of Ce4+ and Cr2O72- in different water samples.

关键词： Multivariate Calibration HPSAM Simultaneous Kintic-Potentiometry Dichromate Cerium(IV)

Ultrasound-Assisted Emulsification Dispersive Liquid-Liquid Microextraction Based on Solidification of Floating Organic Droplet for Separation of Trace Gold Prior to Flame Atomic Absorption Spectroscopy Determination

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American Journal of Analytical Chemistry 2011年第2期2卷 243-249页

作者： Sayed Zia mohammadi mohammad ali karimi ali Shiebani Laleh Karimzadeh Payame Noor University Tehran Iran Department of Chemistry Islamic Azad University Yazd Brunch Yazd Iran

In the present work, a ultrasound-assisted emulsification dispersive liquid-liquid microextraction based on solidification of floating organic droplet method has been developed as a sample preparation method prior to flame atomic absorption spectrometry determination of trace amounts of gold in the standard, wastewater and river water samples. In the proposed method, 1-dodecanol and 5-(4-dimethylamino-benzylidene) were used as extraction solvent and chelating agent, respectively. Several factors that may be affected on the ex-traction process, such as type and volume of the extraction solvent, ionic strength, pH of the aqueous solu-tion, extraction temperature and extraction time were studied and optimized. Under the best experimental conditions, the calibration curve exhibited linearity over the range of 8.0 ng●mL-1- 3.0 μg●mL-1 with a correlation coefficient of 0.9978 and detection limit based on three times the standard deviation of the blank signal was 1.5 ng●mL-1. Eight replicate determinations of 0.2 and 1.0 μg●mL-1 of gold gave a mean absorbance of 0.051 and 0.253 with relative standard deviations of ±2.3% and ±1.5%, respectively. Finally, the developed method was successfully applied to the extraction and determination of gold ions in a silica ore, wastewater, river water and standard samples and satisfactory results were obtained.

关键词： Ultrasound-Assisted Emulsification Microextraction Solidification Floating Organic Droplet Preconcentration Gold Determination Silica Ore

A VERSATILE AND REGIOSELECTIVE SYNTHESIS OF VICINAL AZIDOALCOHOLS USING CROSS-LINKED POLY(4-VINYLPYRIDINE) SUPPORTED AZIDE ION UNDER SOLVENT-FREE CONDITIONS

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Chinese Journal of Polymer Science 2013年第12期31卷 1660-1669页

作者： mohammad ali karimi Zarchi ali Tarabsaz Department of Chemistry College of ScienceYazd University

A new polymeric reagent, cross-linked poly（4-vinylpyridine） supported azide ion, [P4-VP]N3, was introduced as polymeric reagents for efficient and regioselective conversion of epoxides to azidohydrins in the presence of cross-linked poly（4-vinylpyridine） supported sulfuric acid, [P4-VP]H2SO4, as a solid proton source and as catalyst under solvent-free conditions. The advantages of this polymeric reagent over some of those reported in the literature are easy work-up procedure and regeneration of the reagent.

关键词： Ring opening of epoxide fl-Azidoalcohols Poly(4-vinytpyridine) Solvent-free conditions Regioselectivity.

Microstructural evolution,mechanical properties,and corrosion resistance of a heat-treated Mg alloy for the bio-medical application

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Journal of Magnesium and Alloys 2019年第1期7卷 80-89页

作者： mohammad Janbozorgi Kimia karimi Taheri ali karimi Taheri Department of Materials Science and Engineering Sharif University of TechnologyAzadi Ave.TehranIran School of Medicine Shahid Beheshti University of Medical ScienceTehranIran

During the recent years,some Mg based alloys have extensively been considered as a new generation of degradable and absorbable bio-medical *** this work,the Mg-2Zn-1Gd-1Ca(wt%)alloy as a new metallic bio-material was produced by the casting process followed by the heat *** samples of the alloy were solution treated at temperatures of 500,550,and 600°C and then quench aged at temperatures of 125,150,and 175°*** results of SEM-EDS examinations indicated that the alloy microstructure consists ofα-Mg matrix and the Ca_(2)Mg_(6)Zn_(3)and Mg_(3)Gd_(2)Zn_(3)secondary *** regard to the results of Vickers hardness test,the temperatures of 500°C and 150°C were selected as the optimum solutionizing and aging temperatures,***,the dissolution of casting precipitates and production of lattice distortion occurring after the solution treatment led to the reduction in ultimate shear strength up to 21%.But,the precipitation hardening and morphological changes taking place during the aging treatment improved the ultimate shear strength up to 32%.Furthermore,the results of electro-chemical and weight-loss measurements in a simulated body fluid indicated that the heat-treated alloy is a promising candidate for the Mg based alloys recently considered for the bio-medical applications.

关键词： Mg alloys Bio-medical applications Microstructural evolution Mechanical properties Corrosion resistance