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无溶剂条件下磷酸锆纳米粒子作为固体酸催化剂催化苯酚选择性烷基化(英文)

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催化学报 2014年第7期35卷 1136-1147页

作者： Abdol R. Hajipour hirbod karimi Pharmaceutical Research Laboratory Department of Chemistry Isfahan University of Technology Isfahan 84156 IR Iran Department of Neuroscience University of Wisconsin Medical School Madison W153706-1532 USA

A facile synthesis of α-zirconium phosphate(ZP) nanoparticles as an effective, eco-friendly, and recyclable solid acid catalyst is reported. Polyvinylpyrrolidone(PVP) and polyvinyl alcohol(PVA) were used as organic matrix as dispersing agents and served as a template for the nanoparticles. Hydrogen bonds between ZP and PVA or PVP, along the polymer chains, appear to play an important role for improving the dispersion of in situ formed ZP. Following calcination of PVA/ZP or PVP/ZP, pure hexagonal ZP nanoparticles were obtained. The catalysts were characterized by nitrogen sorption, inductively coupled plasma optical emission spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy(FTIR), scanning electron microscopy, and transmission electron microscopy. Pyridine-FTIR and temperature-programmed desorption of NH3 suggest the presence of Brnsted acid sites. The acidic properties of the catalyst were studied in Friedel-Crafts alkylation of phenol by tert-butanol, producing 2-tert-butylphenol, 4-tert-butylphenol, and 2,4-ditert-butylphenol. The alkylation reaction was performed in the presence of catalysts P2O5/Al2O3, P2O5/SiO2, α-ZrP(prepared in the absence of the polymers), and various ionic liquids. The use of the hexagonal ZP nanoparticle catalyst afforded an excellent phenol conversion(86%) and selectivity towards 4-tert-butylphenol(83%) under optimized reaction conditions. The catalyst was easily recovered from the reaction mixture, regenerated, and reused at least four times without significant loss in the catalytic activity.

关键词： Friedel-Crafts烷基化反应二叔丁基苯酚固体酸催化剂纳米粒子磷酸锆选择性溶剂电感耦合等离子体发射光谱法扫描电子显微镜

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磷酸铜锆催化剂上醇选择性氧化（英文）

催化学报 2014年第9期35卷 1529-1533页

作者： Abdol R.Hajipour hirbod karimi Pharmaceutical Research Laboratory Department of Chemistry Isfahan University of Technology Isfahan 84156 Iran Department of Neuroscience University of Wisconsin Medical SchoolMadison WI 53706‐1532 USA

The catalytic activity of copper zirconium phosphate(ZPCu) in the selective oxidation of alcohols to their corresponding ketones or aldehydes, using H2O2 as an oxidizing agent, was studied. The oxida‐tion reaction was performed without any organic solvent, phase‐transfer catalyst, or additive. Steric factors associated with the substrates influenced the reaction. The catalyst was characterized using X‐ray diffraction, inductively coupled plasma atomic emission spectroscopy, energy‐dispersive X‐ray spectroscopy, and scanning electron microscopy. It was shown that the interlayer distance increased from 0.74 to 0.80 nm and the crystallinity was reduced after Cu2+ intercalation into the layers. This catalyst can be recovered and reused three times without significant loss of activity and selectivity.

关键词：选择性氧化磷酸铜磷酸锆电感耦合等离子体原子发射光谱法相转移催化剂扫描电子显微镜 X射线光谱仪醇

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磷酸锆镍上的醇选择性氧化（英文）

催化学报 2015年第7期36卷 1109-1116页

作者： Abdol R.Hajipour hirbod karimi Afshin Koohi Pharmaceutical Research Laboratory Department of ChemistryIsfahan University of Technology Department of Neuroscience University of WisconsinMedical School Young Researchers and Elite Club Shahreza BranchIslamic Azad University

Nickel zirconium phosphate nanoparticles were found to function as efficient catalysts for the selective oxidation of a wide range of alcohols to their corresponding ketones and aldehydes using H2O2 as an oxidizing agent and without any organic solvents, phase transfer catalysts, or additives. The steric and electronic properties of various substrates had significant influence on the reaction conditions required to achieve acetylation. The results showed that this method can be applied for the chemoselective oxidation of benzyl alcohols in the presence of aliphatic alcohols. The catalyst used in the current study was characterized by ICP-OES, XRD, NH3-TPD, Py-FTIR, N2 adsorption-desorption, SEM and TEM. These analyses revealed that the interlayer distance in the catalyst increased from 0.75 to 0.98 nm when Ni2+ was intercalated between the layers, whereas the crystallinity of the material was reduced. The nanocatalyst could also be recovered and reused at least seven times without any discernible decrease in its catalytic activity. This new method for the oxidation of alcohols has several key advantages, including mild and environmentally friendly reaction conditions, short reaction time, excellent yields and a facile work-up.

关键词：选择性氧化脂肪族醇磷酸锆相转移催化剂 ICP-OES 镍纳米粒子反应条件

磷酸锆铁催化无溶剂条件下醇和苯酚乙酰化(英文)

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催化学报 2015年第4期36卷 595-602页

作者： Abdol R.Hajipour hirbod karimi Amir Masti Pharmaceutical Research Laboratory Department of Chemistry Isfahan University of Technology Department of Neuroscience University of Wisconsin Medical School Young Researchers and Elite Club Shahreza Branch Islamic Azad University

Iron zirconium phosphate(ZPFe) nanoparticles were found to function as an efficient catalyst for the acetylation of a wide range of alcohols and phenols using acetic anhydride, generating good to excellent yields under solvent-free conditions. The steric and electronic properties of various sub-strates had a significant influence on the reaction conditions required to achieve the acetylation. The catalyst used in the current study was characterized by inductively coupled plasma-optical emission spectrometry, X-ray diffraction, N2 adsorption-desorption, scanning electron microscopy, and transmission electron microscopy. These analyses revealed that the interlayer distance in the catalyst increased from 7.5 to 9.3  when Fe3+ was intercalated between the layers, whereas the crystallinity of the material was reduced. This nanocatalyst could also be recovered and reused at least six times without any discernible decrease in its catalytic activity. This new method for the acetylation of alcohols and phenols has several important advantages, including mild and environ-mentally friendly reaction conditions, as well as good to excellent yields and a facile work-up.

关键词：无溶剂条件乙酰化磷酸铁磷酸锆苯酚透射电子显微镜感应耦合等离子体高效催化剂

New insights on the role of chondroitin sulfate proteoglycans in neural stem cell–mediated repair in spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1699-1700页

作者： Seyed Mojtaba Hosseini Soheila karimi-Abdolrezaee Department of Physiology and Pathophysiology Spinal Cord Research CentreRady Faculty of Health SciencesUniversity of ManitobaWinnipegMBCanada Manitoba Multiple Sclerosis Research Center WinnipegMBCanada Children Hospital Research Institute of Manitoba WinnipegMBCanada

Extensive neurodegeneration is a hallmark of traumatic spinal cord injury (SCI) that underlies permanent sensorimotor and autonomic impairments (Alizadeh et al.,2019).Following the primary impact,the spinal cord undergoes a cascade of secondary injury mechanisms that are driven by disruption of the blood-spinal cord ba rrier,vascula r inju ry,glial reactivity,neu roinfla mmation,oxidative stress,lipid peroxidation,and glutamate excitotoxicity that culminate in neuronal and oligodendroglial cell death,demyelination,and axonal damage(Alizadeh et al.,2019).To achieve a meaningful functional recovery after SCI,regeneration of new neurons and oligodendrocytes and their successful growth and integration within the neural network are critical steps for reconstructing the damaged spinal cord tissue (Fischer et al.,2020).

关键词： peroxidation Fischer injury

The contribution of steel wallposts to out-of-plane behavior of non-structural masonry walls

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Earthquake Engineering and Engineering Vibration 2023年第1期22卷 243-262页

作者： Fooad karimi Ghaleh Jough Department of Civil Engineering Final International UniversityKyreniaNorth Cyprusvia Mersin 10 Turkey

For years,non-structural masonry walls have received little attention by code developers and professional ***,significant efforts have been made to shed more light on out-of-plane(OOP)behavior of non-structural masonry *** updated provisions of the Iranian seismic code,bed joint reinforcements(BJRs)and steel wallposts have been suggested for *** are horizontal reinforcements;steel wallposts are vertical truss-like elements intended to provide additional OOP restraints for a *** contribution of BJRs has previously been investigated by the *** study is devoted to investigating the contribution of steel wallposts to the OOP behavior of non-structural masonry *** pre-validated 3D finite element(FE)models,the OOP behavior of 180 non-structural masonry walls with varying configurations and details are *** OOP pressure-displacement curve,ultimate strength,the response modification factor,and the cracking pattern are among the results presented in this *** is found that steel wallposts,especially those with higher rigidity,can improve the OOP strength of the *** contribution of wallposts in the case of shorter length walls and walls with an opening are more *** also indicate that masonry walls with wallpost generally have smaller modification factors compared to similar walls without wallpost.

关键词： masonry wall wallpost wind post bed joint reinforcement non-structural masonry wall out-of-plane behavior

Deformed photon-added entangled squeezed vacuum and one-photon states: Entanglement, polarization, and nonclassical properties

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Chinese Physics B 2016年第4期25卷 47-56页

作者： A karimi M K Tavassoly Atomic and Molecular Group Faculty of Physics Yazd University Physics Group Islamic Azad University of Abadeh The Laboratory of Quantum Information Processing Yazd University

In this paper, after a brief review on the entangled squeezed states, we produce a new class of the continuous-variable- type entangled states, namely, deformed photon-added entangled squeezed states. These states are obtained via the iterated action of the f-deformed creation operator A = f（n）a＋ on the entangled squeezed states. In the continuation, by studying the criteria such as the degree of entanglement, quantum polarization as well as sub-Poissonian photon statistics, the two- mode correlation function, one-mode and two-mode squeezing, we investigate the nonclassical behaviors of the introduced states in detail by choosing a particular f-deformation function. It is revealed that the above-mentioned physical properties can be affected and so may be tuned by justifying the excitation number, after choosing a nonlinearity function. Finally, to generate the introduced states, we propose a theoretical scheme using the nonlinear Jaynes-Cummings model.

关键词： squeezed states deformed photon-added entangled states entanglement quantum polarization

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

Characterization of mechanothermally processed nanostructured ZnO

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International Journal of Minerals,Metallurgy and Materials 2016年第5期23卷 588-594页

作者： Saeed karimi Abolghasem Ataie School of Metallurgy and Materials Engineering College of Engineering University of Tehran

In this paper, the Taguchi method with an L9（34） orthogonal array was used as experimental design to determine the optimum conditions for preparing ZnO nanoparticles via a mechanothermal route. ZnSO4·H20 and NaECO3 were used as starting materials. The effects of milling time, NaECO3/ZnSO·H20 molar ratio, and ball-to-powder mass ratio （BPR） on the bandgap （Eg） of ZnO nanoparticles were inves- tigated. The ranges of the investigated experimental conditions were 5-15 h for the milling time （t）, 1.0-1.2 for the Na2COa/ZnSO4·H20 mo- lar ratio （M）, and 10-30 for BPR. The milling time and BPR exhibited significant effects; an increase in milling time reduced the bandgap. The optimum conditions from this study were t3 = 15 h, M1 = l, and BPR2 = 20. Only two significant factors （t3, 15 h; BPR2, 20） were used to estimate the performance at the optimum conditions. The calculated bandgap was 3.12 eV, in reasonable agreement with the experimental results obtained under the optimized conditions.

关键词： mechanothermal treatment synthesis nanoparticles zinc oxide Taguchi methods