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181.
Koji Nagata Tadao Nakamura Josep Batle Soliman Abdalla Ahmed Farouk 《International Journal of Theoretical Physics》2018,57(7):2116-2120
In the short contribution, we consider inequalities of confirming genuine multipartite entanglement. We have a better entanglement witness for a particular mixed state to test genuine multipartite entanglement. Our physical situation is that we measure Pauli observables σ x , σ y , and σ z per side. If the reduction factor is greater than 0.4, then we can confirm the measured quantum state is genuine multipartite entangled experimentally. 相似文献
182.
Burel-Deschamps L Mével M Loizeau D Ayadi F Yaouanc JJ Clément JC Jaffrès PA Giamarchi P 《Journal of fluorescence》2008,18(5):835-841
We report here a study on the physicochemical properties of cationic phospholipids liposomes used for lipoplex formulation
and DNA transfer. The original cationic phospholipids synthesized in our laboratory are first presented with the liposome
formulation process. The second part deals with the liposomes fusogenic properties studied by fluorescence resonant energy
transfer (FRET). The nature of the cationic polar head and the formulation with or without a neutral colipid have a great
influence on the FRET signal. The third part reports the study of the viscosity of the liposome by fluorescence anisotropy
measurements. It has been observed that the vectors having a saturated lipid chain exhibit a more pronounced anisotropy than
those having unsaturated lipid chains. Finally, liposomes formed by a mixture of phospholipids and DC-Chol (a rigid lipid)
leads to increase the anisotropy denoting a more rigid liposome. 相似文献
183.
The effectiveness of antibiotics (ABs) is governed by achieving the adequate pharmacokinetic (PK)/pharmacodynamics (PD) ratio. In this study, fast LC–MS/MS methods were developed and validated for the bioanalysis of cefaclor (CFC), ciprofloxacin (CFC), roxithomycin (RXM) and clindamycin (CLD). Chromatographic separation was performed on a C18 Zorbax-Eclipse Plus (3.5 μm, 100 × 4.6 mm) using isocratic elution. Detection was performed by positive electrospray ionization. The methods were applied for the assessment of PK parameters in volunteers (n = 101, 64 male and 37 female) and the effects of age, body mass index (BMI) and gender were investigated. Good linearity (r 2 ≥ 0.99), accuracy (>86%), precision (CV% ≤ 11) and extraction recovery (>83%) were observed for CFC, CFX, RXM and CLD. Application to PK studies revealed that age and BMI affected the Thalf and the AUC of RXM and CLD (p < 0.023). Gender difference affected the critical PK parameters of the four ABs (Thalf (U = 18; P = 0.036) of CFC, the Cmax of CFX (U = 30; P = 0.017), the Thalf (U = 23; P = 0.009) and AUC (U = 26; P = 0.008) of RXM and CLD), respectively. These results highlight the significance of age and BMI variations for RXM and CLD dosing. Furthermore, it indicates that the gender difference may be considered when adjusting the AB dose. 相似文献
184.
Structural and electronic properties of ZnO under high pressures 总被引:1,自引:0,他引:1
In this work, we use first-principles calculations based on density-functional theory within the local-density approximation (LDA) to investigate the structural and electronic properties of ZnO under high-pressure. We have calculated the ground-state energy, the lattice constant, the bulk modulus, and its pressure derivative of the B4 (wurtzie), B3 (zinc blende), B2 (CsCl) and B1 (rocksalt) phases of ZnO. Moreover, the electronic structure, density of states (DOS) of the B4 (wurtzite) and B1 (rocksalt) phases of ZnO have been calculated. We show that our calculated values compare acceptably well with values reported in the literature. 相似文献
185.
Abdel -Aziz M. Amin A. A. Abd El Raheem Farouk A. Osman 《Fresenius' Journal of Analytical Chemistry》1959,167(1):8-16
Summary Eriochrome black A has been found to be a suitable reagent for the spectrophotometric determination of microgram quantities of cobalt in pure cobalt solutions and in the presence of nickel and some other cations by measuring the decrease in the absorbance of Eriochrome black A at pH 10, caused by the presence of cobalt.Many foreign cations especially nickel were completely masked by EDTA. Amounts as low as about 0.9 to 3 g were determined with fair accuracy. 相似文献
186.
J.L. Aubagnac M. Calmes J. Daunis B. El Amrani R. Jacquier F.M. Devienne R. Combarieu 《Tetrahedron letters》1985,26(12):1497-1500
MBSA-FAB ionization method and mass tandem spectrometry has been applied to the non destructive monitoring of the deprotection step in solid phase peptide synthesis. 相似文献
187.
M. A. Farouk M. N. H. Comsan A. Z. El-Behay A. A. El-Kamhawy A. N. Lvov A. I. Popov 《Zeitschrift für Physik A Hadrons and Nuclei》1967,201(1):52-58
Thep-γ angular correlations in the Be9(d, p, γ)Be10 reaction have been measured in the reaction plane atE d =1.3, 1.5, 1.9, 2.3 and 2.45 MeV for proton anglesθ p =35°, 80° and 120°. The anisotropy of the angular correlations measured forθ p =35° is independent of deuteron energy. A systematic shift of the symmetry axis from the recoil direction has been observed. The shift is 20.5° at Ed=2.45 MeV. The anisotropy decreases with increasing proton angle and vanishes atθ p =120°. 相似文献
188.
Aroylphenylacetylenes Ia-c react with (-butyl hydrazinecarboxylate (IIa) and 2-furylhydrazide (IIb) to give the corresponding hydroxydihydropyrazole derivatives IVa-f. This cyclic structure is supported by chemical transformations. Thus, when compounds IVa-c are heated with acetic anhydride, they yield the corresponding 5-aryl-1-(t-butoxycarbonyl)-3-phenylpyrazoles Va-c which, upon hydrolysis with methanolic potassium hydroxide, produce the corresponding 5(3)aryl-3(5)phenylpyrazoles VI. Spectroscopic data also confirm the suggested cyclic structure IV. 相似文献
189.
Amr Farouk Mohamed Mohsen Hatem Ali Hamdy Shaaban Najla Albaridi 《Molecules (Basel, Switzerland)》2021,26(14)
A comparative study of volatile constituents, antioxidant activity, and molecular docking was conducted between essential oils from Mentha longifolia L., Mentha spicata L., and Origanum majorana L., widely cultivated in Madinah. The investigation of volatile oils extracted by hydrodistillation was performed using Gas Chromatography-Mass Spectrometry (GC-MS). A total number of 29, 42, and 29 components were identified in M. longifolia, M. spicata, and O. majorana representing, respectively, 95.91, 94.62, and 98.42, of the total oils. Pulegone (38.42%), 1,8-cineole (15.60%), menthone (13.20%), and isopulegone (9.81%) were the dominant compounds in M. longifolia oil; carvone (35.14%), limonene (27.11%), germacrene D (4.73%), and β-caryophyllene (3.02%) were dominant in M. spicata oil; terpin-4-ol (42.47%), trans-sabinene hydrate (8.52%), γ-terpinene (7.90%), α-terpineol (7.38%), linalool (6.35%), α-terpinene (5.42%), and cis-sabinene hydrate (3.14%) were dominant in O. majorana oil. The antioxidant activity, assessed using DPPH free radical–scavenging and ABTS assays, was found to be the highest in O. majorana volatile oil, followed by M. spicata and M. longifolia, which is consistent with the differences in total phenolic content and volatile constituents identified in investigated oils. In the same context, molecular docking of the main identified volatiles on NADPH oxidase showed a higher binding affinity for cis-verbenyl acetate, followed by β-elemene and linalool, compared to the control (dextromethorphan). These results prove significant antioxidant abilities of the investigated oils, which may be considered for further analyses concerning the control of oxidative stress, as well as for their use as possible antioxidant agents in the pharmaceutical industry. 相似文献
190.
Amrani A Ma Q Ahmad WS Aizenshtat Z Tang Y 《Chemical communications (Cambridge, England)》2008,(11):1356-1358
(34)S enrichment is shown to occur during sulfurization reactions and for the first time conclusively attributed to an isotope equilibrium effect rather than selective addition of (34)S enriched nucleophiles. 相似文献