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排序方式: 共有201条查询结果,搜索用时 15 毫秒
81.
R. R. Kattabekov K. Z. Mamatkulov D. A. Artemenkov V. Bradnova S. Vokál D. M. Zhomurodov P. I. Zarubin I. G. Zarubina Z. A. Igamkulov N. V. Kondratieva N. K. Kornegrutsa D. O. Krivenkov A. I. Malakhov G. I. Orlova N. G. Peresadko N. G. Polukhina P. A. Rukoyatkin V. V. Rusakova R. Stanoeva M. Haiduc S. P. Kharlamov 《Physics of Atomic Nuclei》2010,73(12):2110-2115
A nuclear track emulsion was exposed to a mixed beam of relativistic 12N, 10C, and 7Be nuclei having a momentum of 2 GeV/c per nucleon. The beam was formed upon charge exchange processes involving 12C primary nuclei and their fragmentation. An analysis indicates that 10C nuclei are dominant in the beam and that 12N nuclei are present in it. The charge topology of relativistic fragments in the coherent dissociation of these nuclei is presented. 相似文献
82.
Dorina Mantu Costel Moldoveanu Alina Nicolescu Calin Deleanu Ionel I. Mangalagiu 《Ultrasonics sonochemistry》2009,16(4):452-454
A new, efficient and general method for preparation of N-substituted-pyridazinones using ultrasound irradiation is reported. Under ultrasound the reaction time decreases substantially, the yields are high and the reaction conditions are mild. It was noticed that substituents at the 3-(6)-position of pyridazone heterocycle have a substantial influence on the reactivity, while the effect of the substituents at the 1-(2)-position seems to be of minor importance. A comparative study of the reactions performed under ultrasound conditions versus at room temperature has been done. 相似文献
83.
D. A. Artemenkov V. Bradnova M. M. Chernyavsky L. A. Goncharova M. Haiduc N. A. Kachalova S. P. Kharlamov A. D. Kovalenko A. I. Malakhov A. A. Moiseenko G. I. Orlova N. G. Peresadko N. G. Polukhina P. A. Rukoyatkin V. V. Rusakova V. R. Sarkisyan R. Stanoeva T. V. Shchedrina S. Vokál A. Vokálová P. I. Zarubin I. G. Zarubina 《Physics of Atomic Nuclei》2008,71(9):1565-1571
The technique of nuclear track emulsions is used to explore the fragmentation of light relativistic nuclei down to the most
peripheral interactions: nuclear “white” stars. A complete pattern of the relativistic dissociation of a 8B nucleus with target
fragment accompaniment is presented. Relativistic dissociation 9Be → 2α is explored using significant statistics, and a relative contribution of 8Be decays from 0+ and 2+ states is established. Target fragment accompaniments are shown for relativistic fragmentation 14N → 3He +H and 22Ne → 5He. The leading role of the electromagnetic dissociation on heavy nuclei with respect to breakups on target protons
is demonstrated in all these cases. It is possible to conclude that the peripheral dissociation of relativistic nuclei in
nuclear track emulsion is a unique tool to study many-body systems composed of the lightest nuclei and nucleons in the energy
scale relevant for nuclear astrophysics.
The text was submitted by the authors in English. 相似文献
84.
85.
Mihalache Valentina Mercioniu Ionel Aldica Gheorghe Pasuk Iuliana 《Journal of Thermal Analysis and Calorimetry》2018,132(1):463-469
Journal of Thermal Analysis and Calorimetry - Azobenzenes undergo reversible trans–cis photo-isomerization and have been studied extensively as photo-responsive materials. Despite their... 相似文献
86.
Preparation of photocrosslinked sol‐gel composites based on urethane‐acrylic matrix,silsesquioxane sequences,TiO2, and Ag/Au Nanoparticles for use in photocatalytic applications
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Andreea L. Chibac Violeta Melinte Tinca Buruiana Ionel Mangalagiu Emil C. Buruiana 《Journal of polymer science. Part A, Polymer chemistry》2015,53(10):1189-1204
An acid urethane oligodimethacrylate based on poly(ethylene glycol) was synthesized and used in the preparation of hybrid composites containing silsesquioxane sequences and titania domains formed through sol‐gel reactions along with silver/gold nanoparticles (Ag/Au NPs) in situ photogenerated during the UV‐curing process. The photopolymerization kinetics studied by Fourier transform infrared spectroscopy and photoDSC showed that the photoreactivity of the investigated formulations depends on the amount of titanium butoxide (5–20 wt %) added in the system subjected to UV irradiation. The introduction of 1 wt % AgNO3/AuBr3 in formulations slightly improved the degree of conversion but diminished the polymerization rates. The formation of hybrid materials comprising predominantly amorphous TiO2/SiO2 NPs, with or without Ag/Au NPs, was confirmed through specific analyses. The evaluation of photocatalytic activity demonstrated that the synthesized hybrid films are suitable for the complete removal of organic pollutants (phenolic compounds) from water under UV irradiation (200–350 min) at low intensity (found in the solar radiation). © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1189–1204 相似文献
87.
Martin N. Gibbons D. Bryan Sowerby Christian Silvestru Ionel Haiduc 《Polyhedron》1996,15(24):4573-4578
Reactions between three diorganodithiophosphinates and diphenylantimony(V) bromide oxide (SbPh2OBr)2, led to antimony reduction while dithiophosphinate oxidation followed a complex path varying in detail with the nature of the organic groups on dithiophosphinate. Antimony(III) dithiophosphinates, SbPh2(S2PR2) where R = Me, Et and Ph, have been isolated and characterised and an X-ray structure determination for the methyl derivative shows weakly associated dimers in the solid state, intermediate between those in (SbPh2S2PPh2)2 and [Sb(4-MeC6H4)2S2PEt]2. 相似文献
88.
The paper reports a new, nonconventional method for the preparation of oxygen-containing niobium compounds, based upon coprecipitation. The coprecipitation product of niobic acid with lead oxalate was used as precursor. Lead metaniobate was obtained by proper thermal treatment of the coprecipitate. The coprecipitate mechanism was studied and the optimal conditions for quantitative precipitation of niobium and lead were established. The mechanism of thermal decomposition of the coprecipitate was investigated by differential thermal analysis and X-ray powder diagrams. The final product of thermal decomposition, lead metaniobate, is formed at 850°C. 相似文献
89.
Eleny-Nicoleta Ionel 《Inventiones Mathematicae》2002,148(3):627-658
We show that any degree at least g monomial in descendant or tautological classes vanishes on ℳ
g,n
when g≥2. This generalizes a result of Looijenga and proves a version of Getzler’s conjecture. The method we use is the study of
the relative Gromov-Witten invariants of ℙ1 relative to two points combined with the degeneration formulas of [IP1].
Oblatum 24-X-2000 & 14-XI-2001?Published online: 18 February 2002 相似文献
90.
Ionel Haiduc 《Journal of Coordination Chemistry》2019,72(1):35-52
This review is a follow up to a previous article [I. Haiduc J. Coord. Chem. (2018) doi:10.1080/00958972.2018.1515429.] which illustrated the concept of inverse coordination with structures in which the coordination center is nitrogen alone (mono- and poly-nitrogen moieties). Here the open and cyclic heteroatom molecules with inorganic skeletons and nitrogen donor sites are presented. Organic nitrogen heterocycles will be treated in a further review.