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排序方式: 共有266条查询结果,搜索用时 15 毫秒
91.
A. Y. Musa W. Ahmoda A. A. Al-Amiery A. A. H. Kadhum A. B. Mohamad 《Journal of Structural Chemistry》2013,54(2):301-308
The effects of the molecular structure on the corrosion inhibition efficiency are investigated by nine methods of calculations. The selected thio compounds were previously identified as corrosion inhibitors for mild steel in the 1.0 M HCl solution. The electronic properties such as highest occupied molecular orbital (EHOMO) energy, lowest unoccupied molecular orbital (ELUMO) energy, dipole moment (μ), and Fukui indices are calculated and discussed. Results show that the corrosion inhibition efficiency increase with the increase in both EHOMO and μ values, respectively, and decrease in ELUMO. QSAR approach is utilized in this study; a good relationship is found between the experimental corrosion inhibition efficiency (IEexp, %) and the theoretical corrosion inhibition efficiency (IEtheor, %). The calculated inhibition efficiency is found closer to the experimental inhibition efficiency with a coefficient of correlation (R 2) of 0.875. 相似文献
92.
Arafa Musa Ehab M. Mostafa Syed Nasir Abbas Bukhari Nasser Hadal Alotaibi Ahmed H. El-Ghorab Amr Farouk AbdElAziz A. Nayl Mohammed M. Ghoneim Mohamed A. Abdelgawad 《Molecules (Basel, Switzerland)》2022,27(4)
For most researchers, discovering new anticancer drugs to avoid the adverse effects of current ones, to improve therapeutic benefits and to reduce resistance is essential. Because the COX-2 enzyme plays an important role in various types of cancer leading to malignancy enhancement, inhibition of apoptosis, and tumor-cell metastasis, an indispensable objective is to design new scaffolds or drugs that possess combined action or dual effect, such as kinase and COX-2 inhibition. The start compounds A1 to A6 were prepared through the diazo coupling of 3-aminoacetophenone with a corresponding phenol and then condensed with two new chalcone series, C7–18. The newly synthesized compounds were assessed against both COX-2 and epidermal growth factor receptor (EGFR) for their inhibitory effect. All novel compounds were screened for cytotoxicity against five cancer cell lines. Compounds C9 and G10 exhibited potent EGFR inhibition with IC50 values of 0.8 and 1.1 µM, respectively. Additionally, they also displayed great COX-2 inhibition with IC50 values of 1.27 and 1.88 µM, respectively. Furthermore, the target compounds were assessed for their cytotoxicity against pancreatic ductal cancer (Panc-1), lung cancer (H-460), human colon cancer (HT-29), human malignant melanoma (A375) and pancreatic cancer (PaCa-2) cell lines. Interestingly, compounds C10 and G12 exhibited the strongest cytotoxic effect against PaCa-2 with average IC50 values of 0.9 and 0.8 µM, respectively. To understand the possible binding modes of the compounds under investigation with the receptor cites of EGFR and COX-2, a virtual docking study was conducted. 相似文献
93.
Claire Förster Dr. Robert Lehn Enis Musa Saritas Prof. Dr. Annette Andrieu-Brunsen 《Angewandte Chemie (International ed. in English)》2023,62(19):e202217806
For miniaturization, as well as for improving artificial nanopore performance, precise local polymer functionalization and the combination of different functionalities are required. Imagining data driven nanopore design automated nanopore functionalization would be beneficial. Using direct laser writing as one option of automated nanopore polymer functionalization visible light induced polymerizations are beneficial. Here, we demonstrate the functionalization of mesoporous silicafilms with two different polymers using automated laser writing. For this we developed a visible light (400–700 nm and 405 nm) N,N(diethylamino)dithiocarbamoylbenzyl(trimethoxy)silane (SBDC) inifierter initiated polymerization. While transferring this visible light induced polymerization using SBDC to a commercially available microscope, direct, automated laser writing, as well as polymer re-initiation was demonstrated. Thereby, polymer spots of 37 and 40 μm in diameter were achieved using 1–5 seconds for each irradiated spot. 相似文献
94.
An adsorptive stripping square wave voltammetric (AdSqW) method was developed for the determination of 3-nitrotyrosine (3-NT), a biomarker of in vivo oxidative damage in Alzheimer, ALS, Parkinson’s, cardiovascular diseases and cancer, in some biological fluids. Voltammetric measurements were performed in 0.30 M (pH 9.0) phosphate solution as supporting electrolyte, a reduction peak was observed at–0.487 V (vs. Ag/AgCl–3 M KCl) with a hanging mercury drop electrode by square wave voltammetry. Cyclic voltammetric measurements showed that the current was adsorption-controlled. LOD and LOQ values were as 0.25 and 1.5 nM, respectively, for the AdSqW method. 3-NT was determined in plasma and cerebrospinal fluid using AdSqW method, which allowed to work at low concentrations. Recovery value was measured as 96.3 ± 2.3%. 相似文献
95.
In this study a kind of poly(azomethine-urethane); (E)-4-((2 hydroxyphenylimino) methyl)-2-methoxyphenyl 6-acetamidohexylcarbamate (HDI-co-3-DHB-2-AP) was prepared as in the literature and employed as a new fluorescent probe for detection of Cd(II) concentration. The photoluminescence (PL) measurements were carried out in the presence of several kinds of heavy metals. HDI-co-3-DHB-2-AP gave a linearly and highly stable response against Cd(II) as decreasing a new emission peak at 562 nm. Possible interferences of other ions were found too low. Detection limit of the sensor was found as 8.86?×?10?4?mol?L?1. Resultantly, HDI-co-3- DHB-2-AP could be effectively used as an optical Cd(II) sensor. 相似文献
96.
Two uranyl complexes having the composition [UO2(L)DMSO] were synthesized using salicyl- and 3,5-dichlorosalicylaldehyde-S-propyl-thiosemicarbazones as starting materials. The S-propyl-thiosemicarbazidato structures in the complexes are N1-3,5-dichlorosalicylidene-N4-salicylidene and N1-salicylidene-N4-3,5-dichlorosalicylidene. The stable solid complexes were characterized by means of elemental analysis, IR and 1H NMR spectroscopies, and the single crystal X-ray diffraction technique. The two complexes, with the same formula, crystallize in different space groups. In the title complexes, the uranium atom is seven-coordinated in a distorted pentagonal-bipyramidal geometry involving an ONNO donor set of the thiosemicarbazidato ligand and an oxygen atom of a DMSO molecule. The two apical positions of the pentagonal bipyramid are occupied by the two oxygen atoms of the trans-dioxouranium group. The relative orientations of the DMSO and S-propyl groups in both complexes are somewhat different due to different crystal packing. 相似文献
97.
Gulzar Hameed Musa Kaleem Baloch Mohsan Nawaz Wajid Rehman 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(5):792-796
Emulsification of oil in water has got a number of industrial as well as medicinal applications, however very little systematic
work has been carried out upon it. Therefore we have considered a very simple system of n-hexane, dispersed in water and tried to understand the mechanism of emulsification by looking into the effect of ultrasonication
time over the quality of emulsion. The techniques employed for the purpose were optical microscopic measurements and turbidity
measurement It has been observed that the distribution of size/number becomes narrowest after minutes of ultrasonication time.
However, if the period is prolonged further then the distribution starts widening. 相似文献
98.
Π-electrons in chemical structure are the unique part of the fundamental particles that modify many interesting properties among the organic semiconductor molecules. By comparing the ground state energy, electronic properties and chemical indices within RHF/6-311G, B3LYP/6-311(G), B3LYP/6-311G(d,p), MP2/6-311G* and Cam-B3LYP/aug-cc-pvdz basis set at level of the theory, we identify that the resonance and the inductive effect of the delocalisation of electrons around the acene molecules could be responsible for acenes electronic and chemical properties. The total energies, energy gaps, HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) energy gaps, electron affinity and ionisation potential are close to the experimental and theoretical results. Among the chemical indices, electrophilicity (ω), electronegativity (χ) and chemical hardness (η) observed to decrease as the acenes ring increasing, whereas the softness (S) and chemical potential (μ) increase with increasing the number of carbons around the acene molecules. The study is extended to electronics and chemical properties of the acene. 相似文献
99.
Solid sampling high resolution continuum source molecule absorption spectrometry (SS-HR-CS MAS) was applied for the determination of chlorine in plastic using the strontium monochloride (SrCl) molecule. For this purpose, 10?µL of 20?g L?1 strontium (prepared from Sr(NO3)2) solution were pipetted with aqueous Cl standards or 0.05 to 4?mg of slivered plastic samples on a platform and introduced into the furnace. Chlorine was determined with the molecular absorption of SrCl at 635.862?nm using 1100?°C and 2200?°C for the pyrolysis and vaporization temperatures, respectively. Aqueous standards were used for calibration. The accuracy of the method was evaluated using a certified polyethylene reference material. The limit of detection and characteristic mass values of the method were 2.5?ng and 0.4?ng, respectively. The chlorine concentrations in various polyethylene beverage containers were determined. 相似文献
100.
R. Vladoiu V. Dinca G. Musa 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(2):433-437
The aim of this paper is concerned with the surface energy evaluation by contact angle measurements of DLC films deposited
by thermionic vacuum arc (TVA) on different substrates: glass plate, zinc foil, stainless steel and alumina foil. TVA is an
original method based on a combination of the evaporation by electron bombardment and anodic arc. The evaluation of the surface
free energy has been carried out by surface energy evaluation system (SEE System). The influence of the experimental conditions
is also investigated. 相似文献