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排序方式: 共有232条查询结果,搜索用时 15 毫秒
1.
We consider the rate of convergence for a class of perturbed hemivariational inequalities in reflexive Banach Spaces. Our results can be viewed as an extension and refinement of some previous known results in this area. 相似文献
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M. A. Misdaq S. Berrazzouk A. Elharti F. Ait Nouh W. Bourzik 《Journal of Radioanalytical and Nuclear Chemistry》2000,246(2):395-401
Uranium and thorium contents were evaluated in water samples collected from different sources of the piedmont of the Middle Atlas mountains by using two types of solid state nuclear track detectors (SSNTD). In addition, the radon (222Rn) and thoron (220Rn) -activities per unit volume of the water samples were also determined. The influence of the water flow rate and altitude on the radon concentration of the water samples belonging to the piedmont of the Middle Atlas mountains was investigated. The hydraulic exchanges between the Middle Atlas water reservoirs and the Turonian aquifer of the neighbouring Tadla plain have been quantified. The results were compared with data given in literature. 相似文献
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Azioune A Slimane AB Hamou LA Pleuvy A Chehimi MM Perruchot C Armes SP 《Langmuir : the ACS journal of surfaces and colloids》2004,20(8):3350-3356
Novel ester-functionalized polypyrrole-silica nanocomposite particles were prepared by oxidative copolymerization of pyrrole and N-succinimidyl ester pyrrole (50/50% initial concentrations), using FeCl3 in the presence of ultrafine silica nanoparticles (20 nm diameter). The N-succinimidyl ester pyrrole monomer was prepared in aqueous solution using 1-(2-carboxyethylpyrrole) and N-hydroxysuccinimide in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. The resulting nanocomposites (N-succinimidyl ester polypyrrole-silica) are raspberry-shaped agglomerates of silica sol particles "glued" together by the insoluble poly(pyrrole-co-N-succinimidyl pyrrole). The N-succinimidyl ester polypyrrole-silica particles were characterized in terms of their size, density, copolymer content, and polydispersity. Scanning electron microscopy and disk centrifuge sedimentometry confirmed that the nanocomposite particles had narrow size distributions. X-ray photoelectron spectroscopy analysis indicated a silica-rich surface and a high surface concentration of N-succinimidyl ester groups. These nanoparticles exhibited good long-term dispersion stability. The chemical stability of the ester functions in aqueous media after several weeks of storage was monitored by FTIR spectroscopy. The functionalized nanocomposites were tested as bioadsorbents of human serum albumin (HSA). The very high amount of immobilized HSA determined by UV-visible spectroscopy is believed to be due to covalent binding. Incubation of the HSA-grafted nanocomposite with anti-HSA resulted in immediate flocculation, an indication that they are alternative candidates for visual diagnostic assays. 相似文献
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A. Ait Haddou M. Berrada G. Paić 《Journal of Radioanalytical and Nuclear Chemistry》1986,102(1):159-175
The yield and average cross section for the reactions11B(p, n)11C,12C(p, )13N,13C(p, n)13N,
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C(d, n)13N,14N(p, )11C,16O(p, )13N,16O(d, n)17F,16O(t, n)18F, and18O(p, n)18F have been measured in different compounds. The charged particles were created in the samples themselves either through recoil by scattering of 14 MeV neutrons off hydrogen and deuterium, or by the (n, t) reaction on6Li using thermal neutrons. The yields of reactions12C(d, n);16O(p, );16O(t, n) and18O(p, n) have been measured using proton, deuteron and triton spectra generated by 14 MeV neutrons in the reactions D(n, p)2n;6Li(n, d);7Li(n, d) and10B(n, d);7Li(n, t) and10B(n, t), respectively. 相似文献
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Zakir O. Ait Karra A. Idouhli R. Elyaagoubi M. Khadiri M. Dikici Burak Aityoub A. Abouelfida A. Outzourhit A. 《Journal of Solid State Electrochemistry》2022,26(10):2247-2260
Journal of Solid State Electrochemistry - In this study, copper (Cu) and silver (Ag)–doped TiO2 nanotubes were fabricated by in situ anodization method to improve their photocatalytic... 相似文献
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Gorelik A. M. Venidiktova O. V. Ait A. O. Barachevsky V. A. 《Russian Journal of General Chemistry》2021,91(12):2656-2659
Russian Journal of General Chemistry - The reaction between phenalenon derivatives containing hydroxy group in peri-position to carbonyl and propynol was studied. A new hybrid compound was... 相似文献
9.
Rapid Assembly of Functionalised Spirocyclic Indolines by Palladium‐Catalysed Dearomatising Diallylation of Indoles with Allyl Acetate
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Dr. Persis Dhankher Dr. Laure Benhamou Dr. Tom D. Sheppard 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(41):13375-13381
Herein, we report the application of allyl acetate to the palladium‐catalysed dearomatising diallylation of indoles. The reaction can be carried out by using a readily available palladium catalyst at room temperature, and can be applied to a wide range of substituted indoles to provide access to the corresponding 3,3‐diallylindolinines. These compounds are versatile synthetic intermediates that readily undergo Ugi reactions or proline‐catalysed asymmetric Mannich reactions. Alternatively, acylation of the 3,3‐diallylindolinines with an acid chloride or a chloroformate, followed by treatment with aluminium chloride, enables 2,3‐diallylindoles to be prepared. By using ring‐closing metathesis, functionalised spirocyclic indoline scaffolds can be accessed from the Ugi products, and a dihydrocarbazole can be prepared from the corresponding 2,3‐diallylindole. 相似文献
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