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排序方式: 共有152条查询结果,搜索用时 62 毫秒
1.
Ali El-Dissouky Eslam S. Abu-Elsoud Afaf Abdel Razik Mohamed K. Awad Hammed H.A.M. Hassan Amel F. Elhusseiny 《应用有机金属化学》2020,34(11):e5953
A series of nanometer-sized spherical sulfonamide imine ligands HL 1 -HL 5 and their copper and zinc complexes were synthesized and fully characterized based on elemental analyses, spectroscopic (UV/vis, FT-IR, NMR, EPR, SEM) studies, molar conductance and thermal analyses. Furthermore, computational studies of HL 1 -HL 5 were carried out by the DFT/B3LYP method. TD-DFT, HOMO and LUMO energy values, chemical hardness, electronegativity, electrophilic index, softness, and other parameters were calculated. Screening against several pathogenic microorganisms indicated that HL 1 exhibited high activity against the tested Gram-negative bacteria relative to other analogues and the inhibition activity is greater than the standard Gentamicin. Analogously, HL 2 exhibited high potent activity against the tested Gram-positive bacteria. Copper complexes exhibited a higher potent activity than zinc analogues. Noteworthy, inhibition activity of [Cu ( L 3 )(OAc)] complex is higher than that of the standard Ampicillin. [Cu ( L 2 )(OAc)] complex displayed a similar activity of the standard bactericides and fungicides in use. The complexes showed appreciated values of MIC against bacterial strains: B. subtilis (MIC = 0.4 μg / mL), E. coli and S. pneumonia (MIC = 1.95 μg / mL) and P. aeruginosa (MIC = 7.81 μg / mL). in vitro cytotoxic activities study proved that [Cu ( L 3 )(OAc)] complex exhibited appreciable activity versus (HEPG-2); IC50 = 4.8 μg/ml, while [Cu( L 2 )(OAc)] complex showed a high activity against (MCF-7); IC50 = 6.2 μg/ml. These results could be considered as new findings of promising antitumor candidates for experimental chemotherapy. 相似文献
2.
On the complex projective line, we construct a Fuchs equation with four given finite singular points and with fundamental solution matrix that has given reducible 2×2 monodromy matrices in the nonresonance case. 相似文献
3.
Journal of Russian Laser Research - We design a miniaturized and highly-sensitive biosensor based on a photonic-crystal aslant cavity (AC) to detect protein concentrations. The AC has seven ring... 相似文献
4.
A Nitrite Electrochemical Sensor Based on Boron‐Doped Diamond Planar Electrochemical Microcells Modified with a Monolacunary Silicotungstate Polyoxoanion 下载免费PDF全文
Yosra Sahraoui Amel Sbartai Sana Chaliaa Abderrazak Maaref Amor Haddad Nicole Jaffrezic‐Renault 《Electroanalysis》2015,27(6):1359-1367
A new boron doped diamond microcells (BDD) was modified, for rapid, selective and highly sensitive determination of nitrite, using a coating film of polyoxometalates (POMs), formed by cyclic voltammetry on the molecular p‐phenylenediamine (PPD) functionalized BDD. The scanning electron microscopy (SEM) technique was used to examine the morphology of (PPD/SiW11) modified (BDD) electrode. It was found that (SiW11) layer was uniformly formed on the electrode surface. It was observed that (BDD/PPD/SiW11) showed excellent electrocatalytic activities towards nitrite ion. Under the selected conditions, the anodic peak maximum at ?0.6 V was linear versus nitrite concentration in the 40 µM–4 mM range, and the detection limit obtained was 20 µM. The newly developed electrode has been successfully applied to the determination of nitrite content in real river water samples. 相似文献
5.
The authors study the existence of mild solutions to a functional differential equation with delay and random effects. They use a random fixed point theorem with a stochastic domain. An example is included to illustrate their results. 相似文献
6.
On the complex projective line, we construct a Fuchs equation with four singular points and with given reducible 2 × 2 monodromy matrices such that the fundamental solution matrix of this equation realizes a given homomorphism. 相似文献
7.
The effect of physical (ultrasonic) and chemical (exposure in 3% solution of acetic acid) activation of filler on the adhesion strength of the protective coatings based on styrene–acrylic dispersions to different substrates is studied. It is shown that modification of kaolins allows one to increase the adhesion strength by 40–50% in the case of the physical activation and by 1.1–1.2 times in the case of chemical activation. The best results are achieved with the use of E-21 dispersion as the polymer matrix. 相似文献
8.
We find the maximum order and initial polar angle of strongly isochronous two-dimensional polynomial reversible systems with
homogeneous nonlinearities of the fourth degree. 相似文献
9.
Houria Hamitouche Abdellah Khelifa Amel Kouache Saâd Moulay 《Research on Chemical Intermediates》2014,40(8):2859-2872
Quaternary ammonium cationic surfactants were synthesized from reformate, a liquid mixture of hydrocarbons (aromatics, naphthenes and paraffins), via chloromethylation/quaternization sequences. The petroleum surfactants thus obtained were evaluated as corrosion inhibitors for carbon steel in 1 M HCl, by gravimetry, potentiodynamic polarization and electrochemical impedance spectroscopy. The corrosion inhibiting efficiency was assessed as functions of surfactant concentration. The results showed that the inhibiting efficiency increased with surfactant concentration; its optimal value of 70 % was for a surfactant concentration of 320 mg/L at 25 °C. Potentiodynamic polarization measurements showed that the mixture acts as a mixed type inhibitor. The corrosion inhibiting mechanism is thought to proceed via an adsorption of the surfactant molecules on the steel surface, generating a film and hindering the active sites. Our experimental adsorption data were found to obey the Langmuir adsorption isotherm. SEM images of the treated specimens, revealing the likely formation of a protective film, demonstrated the inhibiting capacity of the petroleum quaternary ammonium surfactants against the carbon steel corrosion. 相似文献
10.
Amel Souibgui Anne Gaucher Jérôme Marrot Flavien Bourdreux Faouzi Aloui Béchir Ben Hassine Damien Prim 《Tetrahedron》2014
New series of acridines and phenanthrolines have been prepared from β-chlorovinyl aldehydes and various aniline derivatives allowing the installation of valuable substituents, such as ketone, nitro or amino groups at the heterocyclic core. X-ray analyses confirmed the structures of acridines and phenanthrolines as well as the presence of partially hydrogenated rings and their crucial impact on the overall shape of the acridine-based architectures. 1H NMR revealed the helical behaviour of several acridine motives. Comparison of UV data between architectures and influence of number of partially hydrogenated rings is also described. 相似文献