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排序方式: 共有1317条查询结果,搜索用时 15 毫秒
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Brahim Khemaies Rouissi Khalil Soussi-Baatout Amira Khattech Ismail 《Journal of Thermal Analysis and Calorimetry》2021,143(4):3173-3179
Journal of Thermal Analysis and Calorimetry - The thermochemical and kinetic studies of diammonium hydrogen phosphate precipitation in phosphoric acid with ammonia were followed using a... 相似文献
55.
Structural Chemistry - Metal carbonyl complexes, which have been known as effective catalysts since early days, find use in many fields both directly and indirectly. Although the use of metal... 相似文献
56.
Topcuoglu Bulent Ozmen Suleyman Fatih Boztosun Ismail Gulludag Cevdet Bertan 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):783-797
Journal of Radioanalytical and Nuclear Chemistry - In this study, natural (226Ra, 232Th, 40K) and artificial (137Cs) radionuclide activity concentration levels of 63 greenhouse soils collected from... 相似文献
57.
In this study the geometry optimization of monomeric and dimeric forms (D1, D2, and D3) of hydantoin molecule were done using DFT method employing 6?C31++G(d, p) basis set. Harmonic and anharmonic wavenumbers and infrared intensities were computed at the same theory level. Experimental IR spectrum was recorded in the region 400?C4000 cm?1. It has also been characterized by 1H and 13C NMR spectrum. The hydrogen bond (HB) interaction of hydantoin was analyzed via dimers of hydantoin. Detailed vibrational wavenumber shifts and all vibrational mode analyses were reported. Total energy distributions (TED, %) calculations were done to characterize the fundamentals. 相似文献
58.
Simultaneous determination of dextromethorphan hydrobromide (DEX), phenylephrine hydrochloride (PHEN), and carbinoxamine maleate (CAR) in pharmaceutical preparations was performed by using liquid chromatograpy (LC) and spectrophotometry. In LC, the separation
was achieved on a C18 column and the optimal mobile phase for satisfactory separation in a gradient elution program was found
to be acetonitrile-sodium perchlorate solution (5: 95, v/v) initially, then a linear gradient up to 60% acetonitrile in 8
min. In spectrophotometric method, a chemometric technique, principal component regression (PCR), was used. In the method,
the absorbance data matrix corresponding to the concentration data matrix was obtained by the measurement of absorbances in
their zero order spectra by Δλ = 1 nm in the 210–300 nm range. Then, the calibration was obtained by using this data matrix
for the prediction of unknown concentrations of DEX, PHEN, and CAR in their ternary mixture. The methods proposed were validated
and successfully applied to a pharmaceutical preparation, capsule, and the results were compared. 相似文献
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Z. H. Ismail M. M. Ghorab E. M. A. Mohamed H. M. Aly M. S. A. El-Gaby 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2541-2554
Some novel thiourea,1,2,4-triazole, quinazoline, thieno[2,3-d]pyrimi-dine, and thiazolidine derivatives were synthesized to evaluate their antitumor activity. Compound (3f) is nearly as active as reference drug, (Doxorubicin) as positive control. 相似文献
60.
Enantiopure Ferrocene‐Based Planar‐Chiral Iridacycles: Stereospecific Control of Iridium‐Centred Chirality 下载免费PDF全文
Ross A. Arthurs Dr. Muhammad Ismail Christopher C. Prior Dr. Vasily S. Oganesyan Dr. Peter N. Horton Dr. Simon J. Coles Dr. Christopher J. Richards 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(9):3065-3072
Reaction of [IrCp*Cl2]2 with ferrocenylimines (Fc=NAr, Ar=Ph, p‐MeOC6H4) results in ferrocene C?H activation and the diastereoselective synthesis of half‐sandwich iridacycles of relative configuration Sp*,RIr*. Extension to (S)‐2‐ferrocenyl‐4‐(1‐methylethyl)oxazoline gave highly diastereoselective control over the new elements of planar chirality and metal‐based pseudo‐tetrahedral chirality, to give both neutral and cationic half‐sandwich iridacycles of absolute configuration Sc,Sp,RIr. Substitution reactions proceed with retention of configuration, with the planar chirality controlling the metal‐centred chirality through an iron–iridium interaction in the coordinatively unsaturated cationic intermediate. 相似文献