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Chinese Journal of Polymer Science 2010年第5期28卷 731-743页

作者： abdol-reza hajipour Sakineh Habibi Arnold E.Ruoho Dept.of Pharmacology University of WisconsinMedical SchoolMadison53706-1532WIUSA Pharmaceutical Research Laboratory College of ChemistryIsfahan University of TechnologyIsfahan 84156IR Iran

A novel calix[4]arene derivative 2 with amino functional groups at the lower rim was first prepared via introduction of nitro functional groups and amination of the dinitro derivative of calix[4]arene. The optically active monomers were synthesized by dehydration of L-leucine （and L-isoleucine） and 3,3＇,4,4＇-benzophenonetetracarboxylic- 3,3＇,4,4＇-dianhydride （3） followed by reaction with thionyl chloride to form 5a and 5b. Two methods, polymerization under microwave irradiation and solution polymerization in CH2Cl2/TEA, were then employed to carry out the condensation polymerization of 2 with the optically active monomers 5a and 5b, respectively. The polymerization conditions affected the kind of resulting polymers, poly（amide-imide）s （PAIs） 6a and 6b and poly（ester-imide）s （PEIs） 6a＇ and 6b＇ were obtained selectively in good yields and moderate inherent viscosities. Sorption-extraction experiments were carried out using cram picrate extraction method and verified good binding ability of the resulting calixarene-based polymers towards silver, alkali metal and toxic heavy metal cations. Also thermogravimetric analysis indicated that the resulting PAIs and PEIs were thermally stable.

关键词： Condensation polymerization Ionophores Optically active Toxic heavy metals Polymeric calixarenes Thermal stability.

Control system design for a pressure-tube-type supercritical water-cooled nuclear reactor via a higher order sliding mode method

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Nuclear Science and Techniques 2024年第1期35卷 145-154页

作者： M.hajipour G.R.Ansarifar Department of Nuclear Engineering Faculty of PhysicsUniversity of IsfahanIsfahan 81746-73441Iran

Nuclear power plants exhibit non-linear and time-variable ***,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor(SCWR)is a fourth-generation conceptual *** an SCWR,the non-linear dynamics of the reactor require a controller capable of control-ling the *** this study,a pressure-tube-type SCWR was controlled during reactor power maneuvering with a higher order sliding mode,and the reactor outgoing steam temperature and pressure were controlled *** an SCWR,the temperature,pressure,and power must be maintained at a setpoint(desired value)during power *** point kinetics equations with three groups of delayed neutrons were used in the ***-order and classic sliding mode controllers were separately manufactured to control the plant and were compared with the PI controllers speci-fied in previous *** controlled parameters were reactor power,steam temperature,and ***,for these parameters,the PI controller had certain instabilities in the presence of *** classic sliding mode controller had a higher accuracy and stability;however its main drawback was the chattering *** was highly accurate and stable and had a small computational *** reality,it followed the desired values without oscillations and chattering.

关键词： Supercritical water nuclear reactor Higher order sliding mode controller Steam temperature Steam pressure Point kinetics model

Highly efficient and magnetically separable nano-CuFe_2O_4 catalyzed S-arylation of thiourea by aryl/heteroaryl halides

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Chinese Chemical Letters 2014年第10期25卷 1382-1386页

作者： abdol R.hajipour Morteza Karimzadeh Ghobad Azizi Pharmaceutical Research Laboratory Department of ChemistryIsfahan University of Technology Department of Neuroscience University of Wisconsin Medical School

The non-toxic and magnetically separable nano-CuFeOcatalyzed synthesis of symmetrical aryl sulfides by the reaction of thiourea with a wide variety of aryl halides,including aryl chlorides has been *** yields of products have been obtained under ligand-free conditions and without the use of any expensive catalyst,such as palladium.

关键词： Chalcogenides Ligand-free Heterogeneous catalysis Symmetrical diaryl sulfides Transition metal compounds

无溶剂条件下铜磷酸锆催化醇类和酚类化合物乙酰化(英文)

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催化学报 2014年第12期35卷 1982-1989页

作者： abdol R. hajipour Hirbod Karimi Pharmaceutical Research Laboratory Department of Chemistry lsfahan University of Technology lsfahan 84156 lran Department of Neuroscience University of Wisconsin Medical School Madison W153706-1532 USA Young Researchers and Elite Club Shahreza Branch lslamic Azad University lsfahan lran

Copper zirconium phosphate nanoparticles have been used as an efficient catalyst for the acetyla-tion of a wide range of alcohols and phenols with acetic anhydride in good to excellent yields under solvent-free conditions. The steric and electronic properties of the different substrates had a signif-icant 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 spectroscopy,energy dispersive spectroscopy, 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 8.0  when Cu2+ 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 key advantages, including mild and environmentally 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铜泛醇等离子体发射光谱法高效催化剂透射电子显微镜扫描电子显微镜

三(羟甲基)氨基甲烷改性SiO_2固载钯纳米粒子:合成、表征及其催化Heck偶联反应活性（英文）

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催化学报 2014年第9期35卷 1547-1554页

作者： abdol R. hajipour Ghobad Azizi PharmaceuticalResearchLaboratory DepartmentofChemistrylsfahanUniversityofTechnologyIsfahan84156Iran DepartmentofNeuroscience MedicalSchoolUniversityofWisconsin1300UniversityAvenueMadisonW153706-1532USA

The preparation of supported Pd nanoparticles on Tris(tris(hydroxymethyl)aminomethane)‐ modi‐fied Si O2 gel and their catalytic application in Heck coupling are investigated. The catalyst was char‐acterized using a combination of X‐ray diffraction, transmission electron microscopy, field‐emission scanning electron microscopy, and scanning electron microscopy/energy‐dispersive X‐ray spec‐troscopy. The supported Pd nanoparticles were found to be a highly active and reusable catalyst for the Heck reaction at a low Pd loading(0.02 mol%) because of stabilization by the Tris moieties. Several reaction parameters, including the type and amount of solvent, base, and temperature, were evaluated. The heterogeneity of the catalytic system was investigated using different approaches, and showed that slight Pd leaching into the reaction solution occurred under the reaction condi‐tions. Despite this metal leaching, the catalyst can be reused seven times without significant loss of its activity.

关键词： Heck反应二氧化硅凝胶钯纳米粒子反应合成催化活性场发射扫描电子显微镜交叉偶联三(羟甲基)氨基甲烷

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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

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

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

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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

AN EFFICIENT PARALLEL PROCESSING OPTIMAL CONTROL SCHEME FOR A CLASS OF NONLINEAR COMPOSITE SYSTEMS

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Acta Mathematica Scientia 2017年第3期37卷 703-721页

作者： A. JAJARMT M. hajipour Department of Electrical Engineering University of Bojnord P.O. Box 94531-1339 Bojnord Iran Department of Mathematics Faculty of Basic Sciences Sahand University of Technology P.O. Box 51335-1996 Tabriz Iran

This article presents an efficient parallel processing approach for solving the opti- mal control problem of nonlinear composite systems. In this approach, the original high-order coupled nonlinear two-point boundary value problem （TPBVP） derived from the Pontrya- gin＇s maximum principle is first transformed into a sequence of lower-order deeoupled linear time-invariant TPBVPs. Then, an optimal control law which consists of both feedback and forward terms is achieved by using the modal series method for the derived sequence. The feedback term specified by local states of each subsystem is determined by solving a ma- trix Riccati differential equation. The forward term for each subsystem derived from its local information is an infinite sum of adjoint vectors. The convergence analysis and parallel processing capability of the proposed approach are also provided. To achieve an accurate feedforward-feedbaek suboptimal control, we apply a fast iterative algorithm with low com- putational effort. Finally, some comparative results are included to illustrate the effectiveness of the proposed approach.

关键词： Modal series method nonlinear composite system optimal control parallelprocessing