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661.
Mohammad Javad Zare Sakhvidi Abbas Afkhami Atena Rafiei 《International journal of environmental analytical chemistry》2013,93(12):1365-1377
Epichlorohydrin is used frequently in many industrial processes. Exposure to this pollutant could induce harmful effects. The present work developed a novel solid phase microextraction (SPME) method for time weighted average determination of epichlorohydrin in the air by GC/MS. CAR/PDMS in 0.5?cm retracted mode was selected and the effect of environmental parameters on sampling properties of SPME was examined. Experimental sampling rate for epichlorohydrin (8.89?×?10?3?cm3/min) was slightly less than theoretical value (9.059?×?10?3?cm3/min). There was no significant difference among sampling rates at different temperature and velocities but relative humidity had a significant effect on the sampling rate. Limit of detection for SPME method was 0.8?ng per sample, which is good enough in comparison with the NIOSH 1010 method. Comparison of the results between the developed SPME and the NIOSH 1010 method on standard test atmosphere and field showed satisfactory agreement (y?=?1.162x?+?1.8 r 2?=?0.992 and y?=?1.009x+0.76 r 2?=?0.98 respectively). 相似文献
662.
Behrooz Alirezapour Amir Reza Jalilian Mohammad Javad Rasaee Saeed Rajabifar Kamal Yavari Mohsen Kamalidehghan Fatemeh Bolourinovin Gholamreza Aslani 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):1261-1271
Breast cancer radioimmunoscintigraphy targeting HER2/neu expression is a growing field of work in nuclear medicine research. Trastuzumab is a monoclonal antibody that binds with high affinity to HER2/neu, which is over expressed on breast and other tumors. Developing new tracers for the detection of this cancer is of great interest. In this study, trastuzumab was successively labeled with [64Cu]CuCl2 after conjugation with DOTA-NHS-ester. The conjugate was purified by molecular filtration, the average number of DOTA conjugated per mAb was calculated and total concentration was determined by spectrophotometric method. DOTA–trastuzumab was labeled with 64Cu produced by 68Zn(p,αn)64Cu nuclear reaction (30 MeV protons at 180 μA). Radiochemical purity, integrity of protein after radiolabeling and immunoreactivity of radiolabeled mAb trastuzumab with HER2/neu antigen and SkBr3 cell line were performed by RIA. In vitro stability of radiolabeled mAb in human serum was determined by thin layer chromatography. In vitro internalization studies were performed with the SkBr3 cell line and the tissue biodistribution of the 64Cu–DOTA–trastuzumab was evaluated in wild-type rat (90 ± 5.5 μCi, 2, 6, 12, 24 h p.i.). The radioimmunoconjugate was prepared with a radiochemical purity of higher than 96 ± 0.5 % (ITLC) and specific activity as high as 5.3 μCi/μg. The average number of chelators per antibody for the conjugate used in this study was 5.8/1. The sample was showed to have similar patterns of migration in the gel electrophoresis. The 64Cu–DOTA–trastuzumab showed high immunoreactivity towards HER2/neu antigen and SkBr3 cell line. In vitro stability of the labeled product was found to be more than 94 % in PBS and 82 ± 0.5 % in human serum over 48 h. In vitro internalization studies of the 64Cu–DOTA–trastuzumab showed that up to 11.5 % of the radioimmunoconjugate internalized after 10 h. The accumulation of the radiolabeled mAb in liver, skin, intestine, lung, spleen, kidney and other tissues demonstrates a similar pattern to the other radiolabeled anti-HER2 immunoconjugates. 64Cu–DOTA–trastuzumab is a potential compound for molecular imaging of PET for diagnosis and treatment studies and follow-up of HER2 expression in oncology. 相似文献
663.
Seyyed Javad Sabounchei A. R. Dadrass Sepideh Samiee 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1331-1337
The reaction of the title ylide {PhCOCHP(p-tolyl)3} with Pd(II), Pt(II). Hg(II), and Ag(I) in equimolar ratios using CH3CN, CH3OH, and CH2Cl2 as solvents have yielded [{(p-tolyl)3PCHCOC6H5} PdCl2]2 (I), [{(p-tolyl)3 PCHCOC6H5} PtCl2]2(2), [Hg(NO3)2 {(p-tolyl)3 PCHCOC6H5}](3), and [Ag{(p-tolyl)3 PCHCOC6H5 < eqid1 > 2]+ (4). The IR, 1H 13C, and 31P NMR together with micro analysis data of the products were obtained. 相似文献
664.
665.
Seyyed Javad Sabounchei Mohammad Panahimehr Sadegh Salehzadeh Mehdi Bayat Hamid Reza Khavasi David Morales-Morales 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1743-1758
Abstract The reaction of Ph2PCH2PPh2 (dppm) with 4-methylphenacyl bromide and 2-(bromoacetyl)naphthalene in chloroform produce the new phosphonium salts [Ph2PCH2PPh2CH2C(O)C6H4Me]Br (1) and [Ph2PCH2PPh2CH2C(O)C10H7]Br (2). Further, by reaction of the monophosphonium salts of dppm with the strong base Et3N the corresponding bidentate phosphorus ylides, Ph2PCH2P(Ph)2 = C(H)C(O)C6H4Me (3) and Ph2PCH2P(Ph)2 = C(H)C(O)C10H7 (4) were obtained. The reaction of these ligands with mercury(II) halides in dry methanol led to the formation of the mononuclear complexes {HgX 2[(Ph2PCH2PPh2C(H)C(O)C6H4Me)]} [X = Cl (5), Br (6), and I (7)] and {HgX 2[(Ph2PCH2PPh2C(H)C(O)C10H7)]} [X = Cl (8), Br (9), and I (10)]. Characterization of the obtained compounds was performed by elemental analysis, IR, 1H, 31P, and 13C NMR spectra. The structure of compounds 3 and 10 are unequivocally determined by single crystal X-ray diffraction techniques. X-ray analysis of 10 reveals the presence of mononuclear complex containing Hg atom in a distorted tetrahedral environment. In all complexes, the title ylides are coordinated through the ylidic carbon and the phosphine phosphorus. Computational studies on ligand 4 and complexes 8, 9, and 10 at DFT (B3LYP) level of theory are also reported. It was shown that the formation of P,C-coordinated 1+1 complex 10 is energetically more favored than corresponding P,P-coordinated 1+2 product. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the following free supplemental files: Additional figures] 相似文献
666.
Javad Azizian Khadijeh Yadollahzadeh Hasan Tahermansouri Davood Chobfrosh Khoei Akram Sadat Delbari 《合成通讯》2013,43(14):2110-2120
Urea polyfunctional derivatives were successfully synthesized via a one-pot, five-component nucleophilic addition/Ugi reaction sequence. Simplicity, solvent-free conditions, and good yields of products are advantages of this method. 相似文献
667.
In this study, silica-supported titanium tetrachloride was prepared and used as a novel catalyst for rapid and efficient synthesis of 2,4,5-trisubstituted imidazoles by a three-component, one-pot condensation of 1,2-diketones and aryl aldehydes in excellent yield under solvent-free conditions using conventional heating or microwave irradiation.
668.
Seyed Javad Ahmadi Sodeh Sadjadi Morteza Hosseinpour 《Monatshefte für Chemie / Chemical Monthly》2011,44(24):1163-1168
Abstract
An efficient method for the synthesis of 4-amino-5-pyrimidinecarbonitriles by the three-component reaction of malononitrile, aldehydes, and N-unsubstituted amidines under aqueous conditions using CuO microspheres as catalyst is reported. The catalyst exhibited remarkable reusable activity. 相似文献669.
Ali Ahmadi Mohammad Kamfiroozi Javad Beheshtian Nasser L. Hadipour 《Structural chemistry》2011,22(6):1261-1265
Our main objectives are to address the following fundamental issues: (1) A density functional theory study on the structural and electronic properties of the zigzag single-walled aluminum nitride nanotubes (AlNNTs) with various diameters, using B3LYP/6-31G* level of theory. (2) An ONIOM study on the curvature effect of AlNNTs on the NH3 adsorption process using B3LYP/6-31G* and semiempirical AM1 approaches. Furthermore, a potential energy surface is calculated for NH3 moving toward AlNNT surface. In contrast to semiconducting carbon nanotubes (Louie, Top Appl Phys 80:113, 2001) our calculations confirmed that the HOMO?CLUMO energy gap of AlNNTs increases with an increase of the tube diameter. Additionally, we showed that HOMO/LUMO interaction between NH3 and AlNNTs becomes stronger as the tube diameter decreases. 相似文献
670.
Marilyn M. Olmstead Javad J. Sahbari 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):o719-o720
The oxime of acetamide, viz. N‐hydroxyethanimidamide, C2H6N2O, has a complex hydrogen‐bonding arrangement in its crystal structure, featuring one strong O—H⋯N hydrogen bond together with weaker hydrogen bonding involving the amide groups. Conjugation effects lead to atypical distances and angles. 相似文献