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排序方式: 共有122条查询结果,搜索用时 343 毫秒
61.
Rick L. Paul Elizabeth A. Mackey Rolf Zeisler Rabia O. Spatz Bryan E. Tomlin 《Journal of Radioanalytical and Nuclear Chemistry》2009,282(3):945-950
A combination of instrumental neutron activation analysis (INAA) and prompt gamma-ray activation analysis (PGAA) was used
to value assign 35 elements in SRM soil 2709a (San Joaquin Soil). INAA with counting of short-lived radioisotopes was used
for determination of Al, Au, Ca, Dy, K, Mg, Mn, Na, Ti, and V. Elements determined by INAA with counting of intermediate and
long-lived radioisotopes included As, Ba, Ce, Co, Cr, Cs, Eu, Fe, Hf, La, Lu, Nd, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Yb, Zn, and
Zr. Thermal neutron PGAA was used for the determination of H, B, Si, K, Ti, Mn, Fe, Cd and Gd. Expanded uncertainties were
determined for all values reported. 相似文献
62.
MI Umar MZ Asmawi A Sadikun IJ Atangwho MF Yam R Altaf A Ahmed 《Molecules (Basel, Switzerland)》2012,17(7):8720-8734
This study evaluated the anti-inflammatory effect of Kaempferia galanga (KG) using an activity-guided approach. KG rhizomes were serially extracted with petroleum ether, chloroform, methanol and water. These extracts (2 g/kg each) were tested for their ability to inhibit carrageenan-induced rat paw edema. The chloroform extract was found to exert the highest inhibition (42.9%) compared to control (p < 0.001), hence it was further fractionated by washing serially with hexane, hexane-chloroform (1:1) and chloroform. The chloroform fraction (1 g/kg) showed the highest inhibitory effect (51.9%, (p < 0.001), on carrageenan-induced edema. This chloroform fraction was further fractionated with hexane-chloroform (1:3) and chloroform, and of the two fractions, the hexane-chloroform sub-fraction was the most effective in inhibiting edema (53.7%, p < 0.001). GC-MS analysis of the active sub-fraction identified ethyl-p-methoxycinnamate (EPMC) as the major component, which was re-crystallized. EPMC dose-dependently inhibited carrageenan-induced edema with an MIC of 100 mg/kg. Moreover, in an in vitro study, EPMC non-selectively inhibited the activities of cyclooxygenases 1 and 2, with IC?? values of 1.12 μM and 0.83 μM respectively. These results validate the anti-inflammatory activity of KG which may be exerted by the inhibition of cyclooxygenases 1 and 2. EPMC isolated from this plant may be the active anti-inflammatory agent. 相似文献
63.
Rabia Nessah 《Bulletin des Sciences Mathématiques》2004,128(5):417-431
An existence result for abstract nonlinear inequalities. As a consequence of our result, we obtain some further generalizations of recent known results. According to this result, we show the existence of g-saddle point and Aumann strong equilibrium for a constrained noncooperative game. 相似文献
64.
Rabia Sattar Rubina Mukhtar Muhammad Atif Muhammad Hasnain Ali Irfan 《Journal of heterocyclic chemistry》2020,57(5):2079-2107
The presence of benzoxazole moiety in most of the heterocyclic compounds is well reported. The present literature review mainly highlights the novel synthetic transformation and describes the biological potential of most of the heterocyclic compounds by virtue of presence of benzoxazole framework. Most of the researchers have revealed that benzoxazole derivatives exhibit significant antibacterial, anti-inflammatory, antifungal, anticancer, analgesic, antiviral, anti-tubercular, and anthelmintic activities. Benzoxazole moieties also act as tyrosinase inhibitor and cholesterol ester transfer protein inhibitor. This literature review may provide an opportunity to the chemists to design new derivatives of benzoxazole that proved to be the successful agent in view of safety, effectiveness, and efficacy. 相似文献
65.
Nadia Parveen Rabia Nazir Muhammad Mazhar 《Journal of Thermal Analysis and Calorimetry》2013,111(1):93-99
Tris(bipyridine)nickel(II) chloride (1) and bis(bipyridine)nickel(II) chloride (2) pyrolize at heating rate of 50 °C/min to a maximum of 450 °C for 24 h under an inert atmosphere of flowing argon gas, to yield size-controlled nickel nanoparticles. Thermogravimetric studies of the complexes (1) and (2) and GC–MS analysis of the trapped volatile matter evolved during thermal degradation of the complexes indicate their clean decomposition pathway to zero-valent nickel. Both heating rate and argon gas flow rate affect purity, particle size, and shape of the particles. X-ray powder diffractometry and atomic force microscopy showed the formation of face-centered cubic (fcc) structured nickel particles having particle size in the range of 3.5–5.0 nm. Magnetic susceptibility measurements suggest nickel nanoparticles to be ferromagnetic in nature characterized by particle size–dependent Curie temperature and high coercivity that is comparable to the bulk iron. 相似文献
66.
67.
Sma?n Hocine Chérifa Rabia Mohammed M. Bettahar Michel Fournier 《Reaction Kinetics and Catalysis Letters》2003,79(2):357-364
Cs2.5M0.08H0.26PMo12O40and Cs2.5M0.08H1.26PMo11VO40(M: Ni, Fe) heteopolyanions were selectively prepared, characterized by IR, Raman, 31P NMR, XPS and XRD and tested in the ODH of cyclohexane. The salt structure, and reaction mechanism and kinetics are discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
68.
At?f Koca Musa ?ahin Ahmet Gül Rabia Z. Uslu 《Monatshefte für Chemie / Chemical Monthly》2002,1(2):1135-1145
In this study, the electrochemical properties of metal-free and nickel-containing porphyrazines with eight tosylaminoethylthia groups were investigated using cyclic voltammetry, double potential step chronoamperometry, double potential step chronocoulometry, and controlled potential coulometry. Cyclic voltammetry measurements showed that both compounds exhibit two quasi-reversible and an irreversible reduction waves. The first electron transfer reaction was followed by an irreversible chemical reaction, the second one by a reversible chemical reaction for both species. The electrode processes of metal-free and nickel-containing porphyrazines are diffusion controlled, but the double potential step chronocoulometry measurements indicated that the nickel porphyrazine is adsorbed at the electrode. However, a small adsorption current has no significant effect on the mass transport mechanism of the system. Diffusion coefficients of both compounds were determined by both cyclic voltammetric and chronocoulometric measurements. The diffusion coefficients of the reduced forms of the porphyrazines were found to be smaller than those of the neutral forms. 相似文献
69.
Semra Tepe Çam Canan Aydaş Birol Engin Ülkü Rabia Yüce Talat Aydın Mustafa Polat 《辐射效应与固体损伤》2013,168(6):410-420
Laurel leaf (Laurus nobilis L.) samples that originated from Turkey were analyzed by electron spin resonance (ESR) and thermoluminescence (TL) techniques before and after γ-irradiation. Unirradiated (control) laurel leaf samples exhibit a weak ESR singlet centered at g=2.0020. Besides this central signal were two weak satellite signals situated about 3 mT left and right to it in radiation-induced spectra. The dose–response curve of the radiation-induced ESR signal at g=2.0187 (the left satellite signal) was found to be described well by a power function. Variation of the left satellite ESR signal intensity of irradiated samples at room temperature with time in a long term showed that cellulosic free radicals responsible for the ESR spectrum of laurel leaves were not stable but detectable even after 100 days. Annealing studies at four different temperatures were used to determine the kinetic behavior and activation energy of the radiation-induced cellulosic free radicals responsible from the left satellite signal (g=2.0187) in laurel leaves. TL measurements of the polymineral dust isolated from the laurel leaf samples allowed distinguishing between irradiated and unirradiated samples. 相似文献
70.
This paper investigates the existence of absolute optimal solutions for a partition P in continuous and quasiconcave games. We show that the P-consistency property introduced in the paper, together with the quasiconcavity and continuity of payoffs, permits the existence of P-absolute optimal solutions in games with compact and convex strategy spaces. The P-consistency property is a general condition that cannot be dispensed with for the existence of P-absolute optimal solutions. We also characterize the existence of P-absolute optimal solutions by providing necessary and sufficient conditions. Moreover, we suggest an algorithm for efficiently computing P-absolute optimal solutions. 相似文献