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181.
Let R be a semiprime ring and F be a generalized derivation of R and n??? 1 a fixed integer. In this paper we prove the following: (1) If (F(xy) ? yx) n is either zero or invertible for all ${x,y\in R}$ , then there exists a division ring D such that either R?=?D or R?=?M 2(D), the 2?× 2 matrix ring. (2) If R is a prime ring and I is a nonzero right ideal of R such that (F(xy) ? yx) n ?=?0 for all ${x,y \in I}$ , then [I, I]I?=?0, F(x)?=?ax?+?xb for ${a,b\in R}$ and there exist ${\alpha, \beta \in C}$ , the extended centroid of R, such that (a ? ??)I?=?0 and (b ? ??)I?=?0, moreover ((a?+?b)x ? x)I?=?0 for all ${x\in I}$ . 相似文献
182.
Tougerti A Méthivier C Cristol S Tielens F Che M Carrier X 《Physical chemistry chemical physics : PCCP》2011,13(14):6531-6543
Periodic DFT calculations coupled to a first-principle thermodynamic approach have allowed us to establish a surface phase diagram for the different terminations of the α-Al(2)O(3) (1102) surface in various temperature and water pressure conditions. Theoretical results are compared with previous experimental data from the literature. Under a wide range of temperature and water pressure (including ambient conditions) the most stable surface (denoted C2_1H(2)O in this work) is terminated with singly coordinated hydroxyls on four-fold coordinated aluminium (Al(4C)-μ(1)-OH) while most existing surface models are only considering six-fold coordinated surface Al atoms as in the bulk structure of alumina. The presence of more acidic Al(4C)-μ(1)-OH sites helps explain the low Point of Zero Charge (PZC) (between 5 and 6) determined from the onset of Mo oxoanions adsorption on (1102) single crystal wafers. It is also postulated that another termination (corresponding to the hydration of the non-polar, stoichiometric surface, stable in dehydrated conditions) may be observed in aqueous solution depending on the surface preparation conditions. 相似文献
183.
Nahid Nishat Sumaiya Hasnain Tansir Ahmad Asma Parveen 《Journal of Thermal Analysis and Calorimetry》2011,105(3):969-979
The production of new biocidal polyester Schiff base metal complexes [PESB–M(II)] via polycondensation reaction between chelated
Schiff base diol and adipoyl chloride is reported. The resulting polyesters were characterized by physico-chemical and spectroscopic
methods. The analytical data of all the synthesized polyesters were found to be in good agreement with 1:1 molar ratio of
chelated Schiff base diol to adipoyl chloride. Thermogravimetric analyses of synthesized polyesters were studied by TG in
nitrogen atmosphere up to 1073 K and results indicate that Cu(II) polyester complex exhibited better heat resistant properties
than the other polyesters complexes. Magnetic moment and UV–visible spectra were examined to explain the structure of all
the polyesters which reveled that Mn(II), Co(II), Ni(II) have octahedral geometry while Cu(II) possess a distorted octahedral
geometry. These newly developed polyesters were also tested for their antibacterial activity against several bacteria and
fungi. Among all the tested compounds PESB–Cu(II) possess the highest bactericidal and fungicidal activity. 相似文献
184.
Raouf Medimagh Salma Mghirbi Asma Saadaoui Aurélie Fildier Marlène Desloir-Bonjour Guy Raffin Hans R. Kricheldorf Saber Chatti 《Comptes Rendus Chimie》2013,16(12):1127-1139
New series of polyether-amides were prepared by polycondensation in solution of three diamines based on 1,4-3,6-dianhydrohexitols with two types of diacyl chlorides (sebacoyl and isophtaloyl). Unprecedented diamines based on isomannide and isoidide were elaborated. The corresponding polyether-amides (PeA) were obtained with high yields. They were characterized by different analytical techniques (NMR, MALDI–ToF MS, DSC). The combination of MALDI–ToF MS with NMR spectroscopy allowed us to confirm structure types. DSC measurements revealed an amorphous character for the isophtaloyl family with a high Tg value. The sebacoyl series proved to be semi-crystalline with a high Tm value. Isosorbide-based PeAs demonstrated interesting properties (Tg above 210 °C and Tm above 240 °C) and high viscosity (0.32). 相似文献
185.
Afaf A. Nada Asma M. Mahran Ahmad S. Shawali 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2111-2117
Irradiation of N-phenyl-2-phenylazo-3-oxo-3-[(4-phenyl-5-aryl)-1,2,4-triazol-3-yl)thio]butanamides 4 a–c gave the corresponding title spiro compounds 5 a–c as end products via tandem rearrangement and cyclization of 4 a–c in their excited states. 相似文献
186.
We derive in this paper some new existence and uniqueness results for a nonlinear multi-orders impulsive differential equation subject to fractional multi-point fractional integral boundary conditions. The obtained results are based on the Banach’s contraction theorem as well as Schauder fixed point theorem. Finally, two illustrative examples are given. 相似文献
187.
Fatemeh Vahdati Rad Mohammad Reza Housaindokht Razieh Jalal Hossein Eshtiagh Hosseini Asma Verdian Doghaei Sadegh Sadeghi Goghari 《Journal of fluorescence》2014,24(4):1225-1234
Blocking the division of tumor cells by small-molecules is currently of great interest for the design of new antitumor drugs. The interaction of a new metal complex with DNA was investigated through several techniques. Absorption spectroscopy and gel electrophoresis studies on the interaction of the Cu-complex of (2a-4mpyH)2 [Cu(pyzdc)2 (H2O)2].6 H2O with DNA have shown that this complex can bind to CT-DNA with binding constant 3.99?×?105 M?1. The cyclic voltammetry (CV) responses of the metal complex in the presence of CT-DNA have shown that the metal complex can bind to CT-DNA through partial intercalation mode and this is consistent with molecular docking analysis, quenching process and thermal denaturation experiments. The cytotoxicity of this complex has been evaluated by MTT assay. The results of cell viability assay on DU145 cell line revealed that the metal complex had cytotoxic effects. 相似文献
188.
Asma Tufail Shah Adnan Mujahid Muhammad Umar Farooq Waqar Ahmad Baoshan Li Muhammad Irfan Muhammad Abdul Qadir 《Journal of Sol-Gel Science and Technology》2012,63(1):194-199
The nanoparticles of monovacant lacunary keggin-type polyoxometalate (C19H42N)4H3(PW11O39) has been successfully synthesized by Micelle Directed Method using hexadecyltrimthyl ammonium bromide (CTAB) as a template. Non-ionic copolymer Pluronic F127 was used as a capping agent that helps in formation of nanoparticles by preventing the aggregation during the coating of H3(PW11O39)4- onto the counter ion (C19H42N)+. The synthesized material was characterized by Scanning electron microscope (SEM), TGA, DSC and FT-IR techniques. SEM images indicated that (C19H42N)4H3(PW11O39) nanoparticles possess spherical structure. FTIR results revealed that the structural integrity of monovacant lacunary keggin-type polyoxometalates (POM) was not affected when reducing the size. TGA–DSC results showed that the material was thermally stable (with 37 % weight loss) and POM encapsulates CTAB. The efficiency of synthesized material was checked by applying it as a catalyst for the oxidation of toxic mordant yellow dye i.e., potentially hazardous and non-biodegradable azo dye. The (C19H42N)4H3(PW11O39) nanoparticles gave 96 % dye degradation in 60 min at 60 °C temperature. Moreover, on recycling POM nanoparticles demonstrate 92 % oxidative degradation of mordant yellow dye. 相似文献
189.
Prof. Dr. Babak Karimi Dr. Hesam Behzadnia Dr. Mihnea Bostina Prof. Dr. Hojatollah Vali 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(28):8634-8640
A novel nano‐fibrillated mesoporous carbon (IFMC) was successfully prepared via carbonization of the ionic liquid 1‐methyl‐3‐phenethyl‐1H‐imidazolium hydrogen sulfate ( 1 ) in the presence of SBA‐15. The material was shown to be an efficient and unique support for the palladium nanoparticle (PdNP) catalyst Pd@IFMC ( 2 ) in aerobic oxidation of heterocyclic, benzylic, and heteroatom containing alcohols on pure water at temperatures as low as 40 °C for the first time and giving almost consistent activities and selectivities within more than six reaction runs. The catalyst has also been employed as an effective catalyst for the selective oxidation of aliphatic and allylic alcohols at 70–80 °C. The materials were characterized by X‐ray photoelectron spectroscopy (XPS), N2 adsorption–desorption analysis, transmission electron microscopy (TEM), and electron tomography (ET). Our compelling XPS and ET studies showed that higher activity of 2 compared to Pd@CMK‐3 and Pd/C in the aerobic oxidation of alcohols on water might be due to the presence of nitrogen functionalities inside the carbon structure and also the fibrous nature of our materials. The presence of a nitrogen heteroatom in the carboneous framework might also be responsible for the relatively uniform and nearly atomic‐scale distribution of PdNPs throughout the mesoporous structure and the inhibition of Pd agglomeration during the reaction, resulting in high durability, high stability, and recycling characteristics of 2 . This effect was clearly confirmed by comparing the TEM images of the recovered 2 and Pd@CMK‐3. 相似文献
190.
Karimi B Behzadnia H Rafiee M Vali H 《Chemical communications (Cambridge, England)》2012,48(22):2776-2778
A novel nano-fibrillated mesoporous carbon (IFMC) was found to be an effective modifier in combination with ionic liquid 1-octylpyridinum hexafluorophosphate (OPFP) as a binder to give impregnated graphite electrodes with outstanding electrochemical performances. 相似文献