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101.
Bouchra Belhaj Abdallah Ahmed Landoulsi Abdelwaheb Chatti 《Journal of Saudi Chemical Society》2018,22(1):110-118
The instant biosynthesis of silver nanoparticles under static electromagnetic induction, its antibacterial activity and its post exposure monitoring were reported here. A mix of silver nitrate solution and Ruta chalepensis leaf extract was irradiated by a static electromagnetic field (SMF) of 200 mT. The characteristics and stability of the biosynthesized silver nanoparticles (Ag NPs) were determined. Compared to the non-irradiated exposure, the morphology and state of the obtained material change once the exposition to SMF is turned off. Shifting from 453 to 473 nm, the percentage of the needles shaped silver nanoparticles increased and continue to win and dominate the biomixture toward the spherical silver nanoparticles. TEM microscopy showed a wide range of silver materials designed in different nanoscale morphology and beyond where they undergo major changes affecting mainly the size, shape and form (dispersity) of nanosilver. 相似文献
102.
Badawi HM Förner W El Ali B Al-Durais AR 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,70(5):983-990
The structural stability of sulfolane (tetrahydrothiophene1,1-dioxide) and 3-sulfolene (dihydrothiophene1,1-dioxide) was investigated by DFT-B3LYP and ab initio MP2 calculations with 6-311+G**) basis set. The calculated symmetric ring-puckering potential of 3-sulfolene at the B3LYP level is consistent with a flat minimum that corresponds to a planar ring but at the MP2 level with a double minimum with a low barrier of about 193calmol(-1) to ring planarity in reasonable agreement with experimental results. From the calculations at the two levels of theory sulfolane was predicted to exist predominantly in the twist conformation. The vibrational wavenumbers were calculated at the MP2/6-31G** level of theory and the potential energy distributions PED among the symmetry coordinates of the normal modes were computed for the low-energy structure of the molecules. Complete vibrational assignments were provided on the basis of the calculated PED values. The experimental infrared and Raman spectra of the two molecules were compared to the calculated ones. 相似文献
103.
Abdallah Hamze 《Tetrahedron letters》2008,49(15):2429-2431
Totally regioselective hydrosilylation of functionalized terminal arylalkynes was achieved using PtCl2 associated with the air-stable and bulky Xphos ligand with various silanes. Regardless of the electronic nature of the substituents on the aromatic ring, a single β-(E)-vinylsilane was obtained in excellent yields. 相似文献
104.
Owono Owono LC Ben Abdallah D Jaidane N Lakhdar ZB 《The Journal of chemical physics》2008,128(8):084309
Ab initio transition dipole moments between states of the triplet manifold of NH radical are determined at the complete active space self-consistent field, followed by the internally contracted multireference singles plus doubles configuration interaction level of theory with a modified aug-cc-pVTZ basis set that accounts for valence-Rydberg interactions. This enables the computation of various radiative characteristics such as Einstein coefficients, radiative lifetimes, and oscillator strengths. These properties concern as well valence and Rydberg states. For the valence states, only the (0, 0) band of the A 3 Pi-X 3 Sigma(-) transition has received some important amount of attention. Data for the other transitions are rather scarce and sometimes inexistent. The results obtained in this work show good agreement with the available experimental data in comparison to other theoretical numbers reported in the literature. 相似文献
105.
Reem Ibrahim Al-Wabli Tamer Mostafa Mohamed Hafez Sakr Mohammed Abdou Khedr Adly Abdallah Selim Mohamed Abd El-Motaleb Abd El-Rahman Wafaa Abdou Zaghary 《Chemistry Central journal》2016,10(1):73
Background
One of the most popular techniques for cancer detection is the nuclear medicine technique. The present research focuses on Platelet-12-lipoxygenase (P-12-LOX) as a promising target for treating and radio-imaging tumor tissues. Curcumin was reported to inhibit this enzyme via binding to its active site.Results
A novel curcumin derivative was successfully synthesized and characterized with yield of 74%. It was radiolabeled with the diagnostic radioisotope technetium-99m with 84% radiochemical yield and in vitro stability up to 6 h. The biodistribution studies in tumor bearing mice confirmed the high affinity predicted by the docking results with a free binding energy value of (ΔG ?50.10 kcal/mol) and affinity (13.64 pki) showing high accumulation in solid tumor with target/non-target ratio >6.Conclusion
The newly synthesized curcumin derivative, as a result of a computational study on platelet-12 lipoxygenase, showed its excellent free binding energy (?G ?50.10 kcal/mol) and high affinity (13.64 pKi). It could be an excellent radio-imaging agent that targeting tumor cells via targeting of P-12-LOX.
106.
Hegeler F. Partridge M.D. Schamiloglu E. Abdallah C.T. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2000,28(3):567-575
We first reported the operation of a relativistic backward-wave oscillator (BWO) in the so-called cross-excitation regime in 1998. This instability, whose general properties were predicted earlier through numerical studies, resulted from the use of a particularly shallow rippled-wall waveguide [slow wave structure (SWS)] that was installed in an experiment to diagnose pulse shortening in a long-pulse electron beam-driven high-power microwave (HPM) source. This SWS was necessary to accommodate laser interferometry measurements along the SWS during the course of microwave generation. Since those early experiments, we have studied this regime in greater detail using two different SWS lengths. We have invoked time-frequency analysis, the smoothed-pseudo Wigner-Ville distribution in particular, to interpret the heterodyned signals of the radiated power measurements. These recent results are consistent with earlier theoretical predictions for the onset and voltage scaling for this instability. This paper presents data for a relativistic BWO operating in the single-frequency regime for two axial modes, operating in the cross-excitation regime, and discusses the interpretation of the data, as well as the methodology used for its analysis. Although operation in the cross-excitation regime is typically avoided due to its poorer efficiency, it may prove useful for future HPM effects studies 相似文献
107.
Giuseppe Vasapollo Antonio Scarpa Giuseppe Mele Ludovico Ronzini Bassam El Ali 《应用有机金属化学》2000,14(11):739-743
Palladium acetate [Pd(OAc)2] and 1,4‐bis(diphenylphosphino)butane (dppb) catalyse regioselective cyclocarbonylation of bisallyl derivatives of bisphenols affording seven‐membered ring bislactones in good yields. Double cyclocarbonylation reactions carried out using different conditions afforded bislactones with two different ring sizes (7–6 and 7–5‐membered). Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
108.
Bassam Abbas Yousef T. Salman Moustafa S. El-Daher 《Journal of Macromolecular Science: Physics》2015,54(12):1457-1465
Photoinduced birefringence in poly(methyl methacrylate) (PMMA), polymeric thin films doped with di-azo Sudan G was investigated. A pump-probe method was used to study the dynamic behavior of the birefringence. The mechanism for the inducement of birefringence is discussed in terms of the photoisomerization of the di-azo Sudan G molecules. The results showed that the dynamic evolution of the photoinduced birefringence was such that the average birefringence increased, saturated, and then decreased with respect to the laser pump intensity. Also, an exponential-like relationship was observed between both the saturation and the isotropic states of the averaged transmitted probe beam (expressing the residual anisotropy) and the birefringence on one hand, and the intensity amplitudes of the pumping powers on the other hand. 相似文献
109.
110.