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排序方式: 共有253条查询结果,搜索用时 46 毫秒
101.
Safaei-Ghomi Javad Akbarzadeh Zeinab Teymuri Raheleh 《Research on Chemical Intermediates》2019,45(6):3425-3439
Research on Chemical Intermediates - Zinc oxide nanoparticles immobilized on a graphitic carbon nitride (ZnS NPs/g-C3N4) nanocomposite were applied as an organometallic recyclable catalyst in the... 相似文献
102.
103.
Mohamed K. Abd El-Rahman Hala E. Zaazaa Samah S. Abbas Badr El-Zeany Zeinab A. EL-Sherif Dalia A. EL-Haddad 《中国化学快报》2015,26(6):714-720
A comparative study was conducted using two designs of a roxatidine acetate (ROX)-selective electrode; a conventional liquid inner contact called electrode A and a graphite-coated solid contact called electrode B. The fabrication of electrodes was based on roxatidine-tetraphenylborate (ROX-TPB) as an ion-association complex in a PVC matrix using different plasticizers. Electrode A has a linear dynamic range of 2.2×10-5 mol/L to 1.0×10-2 mol/L, with a Nernstian slope of 54.7 mV/decade and a detection limit of 1.4×10-6 mol/L. Electrode B shows linearity over the concentration range of 1.0×10-6 mol/L to 1.0×10-2 mol/L, with a Nernstian slope of 51.2 mV/decade and a limit of detection of 1.1×10-7 mol/L which is remarkably improved as a result of diminishing ion fluxes in this solid contact, ion-selective electrode. The proposed sensors display useful analytical characteristics for the determination of ROX in bulk powder and its pharmaceutical formulation. The present electrodes show clear discrimination of ROX from several inorganic, organic ions, sugars, some common drug excipients and the degradation product (3-[3-(1-piperidinyl methyl) phenoxy] propyl amine) of ROX. Furthermore, the proposed electrodes were utilized for the determination of ROX in human plasma, where electrode B covers drug Cmax which indicated its applicability to pharmacokinetic, bioavailability and bioequivalent studies. The results obtained by the proposed electrodes were statistically analyzed and compared with those obtained by a reported HPLC method. No significant difference for either accuracy or precision was observed. 相似文献
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105.
Elsharkawy Zeinab F. Hammad Mohammed E. 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(2):741-752
Journal of Radioanalytical and Nuclear Chemistry - This paper presents an efficient approach for automated fault detection and diagnosis of the distillation column by analyzing the gamma intensity... 相似文献
106.
Fatma E. M. El-Baih Feriyal M. Abu-Loha Zeinab Gomaa Ibrahim M. Al-Najjar 《Transition Metal Chemistry》1994,19(3):325-328
Summary Schiffs bases derived from 2-aminothiazole and substituted benzaldehydes were reacted with [RhCl(PPh3)3] or [Rh(-Cl)(COD)]2 (COD = 1,5-cyclooctadiene) in the presence of four equivalents of PPh3 to give RhIII cyclometallated complexes of the type [RhHCl{(X-benzylidene) thiazole}(PPh3)2], in which the imine C-H added oxidatively to the metal. The complexes were characterized using i.r., u.v. and n.m.r. spectroscopy. The disposition of the hydride ligand was inferred as trans to a N-donor ligand. 相似文献
107.
Zeinab Hajjar Mohammad Kazemeini Shokoufe Tayyebi 《Phosphorus, sulfur, and silicon and the related elements》2016,191(9):1256-1261
A Co-Mo/graphene oxide (GO) catalyst has been synthesized for the first time for application in a defined hydrodesulfurization (HDS) process to produce sulfur free naphtha. An intelligent model based upon the neural network technique has then been developed to estimate the total sulfur output of this process. Process operating variables include temperature, pressure, LHSV and H2/feed volume ratio. The three-layer, feed-forward neural network developed consists of five neurons in a hidden layer, trained with Levenberg–Marquardt, back-propagation gradient algorithm. The predicted amount of residual total sulfur is in very good agreement with the corresponding experimental values revealing a correlation coefficient of greater than 0.99. In addition, a genetic algorithm (GA) has been employed to optimize values of total sulfur as well as reaction conditions. 相似文献
108.
Zeinab Kamali Mahmood Lashkarizadeh Bami 《Journal of Fourier Analysis and Applications》2016,22(6):1225-1234
The concepts of BSE property and BSE algebras were introduced and studied by Takahasi and Hatori in 1990 and later by Kaniuth and Ülger. This abbreviation refers to a famous theorem proved by Bochner and Schoenberg for \(L^1({\mathbb {R}})\), where \({\mathbb {R}}\) is the additive group of real numbers, and by Eberlein for \(L^1(G)\) of a locally compact abelian group G. In this paper we investigate this property for the Banach algebra \(L^p(S,\mu )\;(1\le p<\infty )\) where S is a compact totally ordered semigroup with multiplication \(xy=\max \{x,y\}\) and \(\mu \) is a regular bounded continuous measure on S. As an application, we have shown that \(L^1(S,\mu )\) is not an ideal in its second dual. 相似文献
109.
Loghavi Mohammad Mohsen Zarei-Jelyani Mohammad Babaiee Mohsen Niknam Zeinab Eqra Rahim 《Journal of Solid State Electrochemistry》2023,27(8):2237-2250
Journal of Solid State Electrochemistry - Electrocatalysts have a key role in the reactions of vanadium redox flow batteries (VRFB). A practical immersion-drying method is used to decorate graphene... 相似文献
110.
Spiro[dibenzo[b,i]xanthene-13,3′-indoline]-pentaones and 5H-dibenzo[b,i]xanthene-tetraones are synthesized from the condensation of 2-hydroxynaphthalene-1,4-dione with isatins or aldehydes. 相似文献