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81.
Valiollah Mirkhani Shahram Tangestaninejad Majid Moghadam Bahram Yadollahi Ladan Alipanah 《Monatshefte für Chemie / Chemical Monthly》2004,135(10):1257-1263
Summary. Efficient esterification of primary and sterically-hindered secondary or tertiary alcohols with acetic anhydride was achieved in the presence of ammonium decatungestocerate(IV) icosahydrate, (NH4)8[CeW10O36]·20H2O, as catalyst in high yields. Primary and secondary alcohols were also converted to their corresponding acetates and formates with acetic acid and ethyl formate in the presence of this catalyst. Easy work-up, non-toxicity, reusability, and stability of the catalyst are noteworthy advantages of this method. 相似文献
82.
High-intensity focused ultrasound (HIFU) has the potential to become a modality of treatment for a wide range of clinical conditions. HIFU enables non-invasive, selective ablation of tissues including tumors and punctured vessels. Another promising area of research within the field of therapeutic ultrasound is the application of HIFU to treat neurological disorders by selectively targeting the brain, spinal cord, or nerves. This paper provides an overview of the current applications of focused ultrasound in medicine with an emphasis on its use in the fields of neurology and neurosurgery. 相似文献
83.
Photocatalytic degradation of norfloxacin and its intermediate degradation products using nitrogen‐doped activated carbon–CuS nanocomposite assisted by visible irradiation 下载免费PDF全文
We have synthesized a nitrogen‐doped activated carbon (NAC) derived from oak using KOH and N2 thermal treatment at 400 °C as well as CuS nanoparticles. The NAC was decorated with the synthesized CuS to apply as a photocatalyst for degradation of norfloxacin (NOR). Before its application for photodegradation, the adsorbent/photocatalyst structural properties were investigated using X‐ray diffraction, X‐ray photoelectron spectroscopy, Raman spectroscopy and scanning electron microscopy. The photocatalytic degradation of NOR was successfully done under visible light using NAC–CuS. The results revealed that the investigated fluoroquinolone degraded very efficiently and pseudo‐first‐order kinetics was adopted for the photodegradation process. In addition, isothermal studies showed that the adsorption process in darkness followed the Langmuir model. The degradation characteristics of the NAC–CuS photocatalyst were studied for 120 min and 15 h under visible light for degradation of NOR, exhibiting a good efficiency for NOR removal. During 120 min of degradation, some intermediate degradation products that can be considered as secondary pollutants were produced. Then, to degrade these pollutants the radiation time was increased up to 15 h. The results displayed a perfect degradation of NOR and its secondary pollutants. The effective variables including pH, degradation time and photocatalyst dosage were optimized and studied in a multivariate method using Design Expert 7. Determination of photodegradation products was carried out using liquid chromatography–mass spectrometry. The results are of significance for estimating the environmental fate of NOR in aqueous media. 相似文献
84.
Mahboubeh Rostami Ahmad R. Khosropour Valiollah Mirkhani Iraj Mohammadpoor-Baltork Majid Moghadam Shahram Tangestaninejad 《Journal of the Iranian Chemical Society》2014,11(5):1493-1501
Di[1,6-bis(3-methylimidazolium-1-yl)hexane] decatangstate ([C6(MIm)2]2W10O32) was found to be a novel, powerful and effective catalyst for the preparation of N-benzoylglycine carbamides as derivatives of AT-130 via one-pot multicomponent reaction performed under microwave irradiations. The products were obtained in high to excellent yields, thus providing a unique strategy to the large-scale synthesis of these compounds. 相似文献
85.
Chloromethylated polystyrene supported copper (II) bis–thiazole complex: Preparation,characterization and its application as a heterogeneous catalyst for chemoselective and homoselective synthesis of aryl azides 下载免费PDF全文
Zahra Dehbanipour Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Iraj Mohammadpoor‐Baltork 《应用有机金属化学》2018,32(9)
This work deals the synthesis of aryl azides catalyzed by heterogeneous copper (II) complex of 3,5–bis (2–benzothiazolyl) pyridine, [Cu (II)(BTP)(OTf)2], immobilized on chloromethylated polystyrene, [Cu (II)(BTP)(OTf)2]@CMP. The prepared catalyst was characterized by different analytical techniques such as X‐ray diffraction (XRD), thermogravimetric analysis (TGA), field emission scanning electron microscopy (SEM), energy dispersive X–ray spectroscopy (EDX), elemental analysis, and FT‐IR and UV–Vis spectroscopic methods. This catalytic system showed excellent activity in the synthesis of aryl azides by the reaction of aryl halides with sodium azide in the presence of catalytic amounts of [Cu (II)(BTP)(OTf)2]@CMP. Moreover, this unique catalyst could be recovered easily and reused several times without any considerable loss of its catalytic activity. 相似文献
86.
Dodecatungstocobaltate heteropolyanion encapsulation into MIL‐101(Cr) metal–organic framework scaffold provides a highly efficient heterogeneous catalyst for methanolysis of epoxides 下载免费PDF全文
Afsaneh Marandi Shahram Tangestaninejad Majid Moghadam Valiollah Mirkhani Adam Mechler Iraj Mohammadpoor‐Baltork Farnaz Zadehahmadi 《应用有机金属化学》2018,32(2)
A heterogeneous catalyst was synthesized by encapsulation of a Keggin‐type heteropolytungstate, potassium dodecatungstocobaltate trihydrate, K5[CoW12O40]·(Co‐POM), into chromium(III) terephthalate (MIL‐101). Encapsulation was achieved via a ‘build bottle around ship’ strategy in aqueous media, following a hydrothermal method. The structure of the resulting crystalline solid was characterized using X‐ray diffraction, correlated with Fourier transform infrared and UV–visible spectroscopy. The metal content was analysed using optical emission spectroscopy. Transmission electron microscopy was used to measure particle size and N2 adsorption in a Brunauer–Emmett–Teller instrument to characterize the specific surface area. The catalytic activity was investigated using methanolysis of epoxides under mild conditions as a test reaction. The turnover frequency of the heterogeneous Co‐POM@MIL‐101 catalyst was more than 20 times higher than that of the homogeneous Co‐POM catalyst. The Co‐POM@MIL‐101 catalyst was reused several times with negligible leaching of Co‐POM and with no considerable loss of its initial efficiency. The simplicity of preparation, extraordinary stability and high reactivity make Co‐POM@MIL‐101 an exceptional catalytic matrix that is easily separable from reaction media. 相似文献
87.
88.
Mehdi Shafiee Ahmad Reza Khosropour Iraj Mohammadpoor-Baltork Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Hamid Reza Khavasi 《Molecular diversity》2012,16(4):727-735
An expeditious, straightforward and efficient synthesis of diversely naphtho[1,2-e][1,3]oxazines via one-pot condensation reaction of ??- naphthol, 3-amino-5-methylisoxazole and arylaldehydes catalyzed by bismuth(III) trifluoromethanesulfonate is described. The reaction preferentially afforded 1,3-trans oxazines. 相似文献
89.
Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Iraj Mohammadpoor-Baltork Saeedeh Gorjipoor Parvin Yazdani 《合成通讯》2013,43(3):552-561
Efficient ring opening of epoxides with aromatic amines catalyzed by ZrO(OTf)2 is reported, and the corresponding β amino (beta-amino acid) alcohols were obtained in high yields in CH3CN as solvent. The reactions were carried out at room temperature and in the presence of only 1.25 mol% of ZrO(OTf)2. This catalyst can be reused several times without loss of its activity. 相似文献
90.
There is a high overvoltage in the oxidation of methanol in fuel cells, and so modified electrodes are used to decrease it. A modified electrode that used Ni(Ⅱ) loaded analcime zeolite to catalyze the electrooxidation of methanol in alkaline solution was proposed. Analcime zeolite was synthesized by hydrothermal synthesis, and Ni(Ⅱ) ions were incorporated into the analcime structure, which was then mixed with carbon paste to prepare modified electrode. The electrocatalytic oxidation of methanol on the surface of the modified electrode in alkaline solution was investigated by cyclic voltammetry and chronoamperometry. The effects of the scan rate of the potential, concentration of methanol, and amount of zeolite were investigated. The rate constant for the catalytic reaction of methanol was 6×103 cm3 mol-1 s-1 from measurements using chronoamperometry. The proposed electrode significantly improved the electron transfer rate and decreased the overpotential for methanol oxidation. 相似文献