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1.
R. U. Khafizov N. Severijns O. Zimmer H. -F. Wirth D. Rich S. V. Tolokonnikov V. A. Solovei M. R. Kolhidashvili 《JETP Letters》2006,83(1):5-9
The aim of this work is the experimental observation of and research into a rare neutron mode, the radiative beta decay, where
a new particle, the radiative gamma quantum, is formed along with the expected decay products: a beta electron, a recoil proton,
and an antineutrino. The discovery of this rare neutron decay mode was conducted through identification of triple-coincidence
events: simultaneous registration of a beta electron, a proton, and a radiative gamma quantum. The ordinary neutron decay
was registered by double coincidences of a beta electron and a recoil proton. The statistics collected allow one to deduce
the branching ratio (BR) BR = (3.2 ± 1.6) × 10−3 (90% C.L.) in the gamma energy region greater than 35 keV. This value of BR is consistent with standard electroweak theory.
The text was submitted by the authors in English.
An erratum to this article is available at . 相似文献
2.
3.
Iradj Ouveysi Andrew Wirth Annie Yeh Osman Oğuz 《Annals of Operations Research》2003,124(1-4):285-293
We consider the problem of providing a minimum cost multi-service network subject to one link failure scenarios. We assume our network is fully meshed and demand is satisfied by using direct or two hop-paths. We provide a large scale linear programming formulation and propose and test two effective heuristics. 相似文献
4.
Alkaline hydrolysis of 1-benzyl-4, 4-dicyanoethyl-5-oxo-1,3,4,5-tetrahydro-benzo-[cd]indole under controlled conditions leads to 4-benzyl-4,6,7,8-tetrahydro-10a, 6a-iminopropanoindolo[3,3a,4-gh]quinoline-9(10H),12-dione ( 2a ), the first representative of such a ring system. Alkylation of this di-lactam affords the N-monoalkyl ( 2b ), the N, N'-dialkyl ( 3 ), and the N, O-dialkyl ( 4 ) derivatives according to the conditions employed. Treatment of compounds such as 2 with sodium in liquid ammonia results in the opening of one of the lactam rings by a stereoelectronically controlled reductive cleavage of the benzylamine bond; subsequent protonation proceeds stereospecifically to give trans-octahydroindolo[3,3a, 4-gh]quinolines (viz. 5 ). The NMR. spectra and the mechanism of the reductive ring opening are discussed. 相似文献
5.
New Methods for Synthesis of Organohalogenostibanes Organohalogenostibanes RSbX2 (R = CH3, C6H5; X = Cl, Br) and R2SbX (R = C6H5; X = Cl) are received in good yields by alkylation or arylation of the corresponding antimony halides with Pb(CH3)4, Sn(CH3)4, Sb(CH3)3, or Sb(C6H5)3. These methods are better than those, described in the literature for preparation of the compounds. 相似文献
6.
7.
[reaction: see text]. Polymer-bound chiral electrophilic selenium reagents have been developed and applied to stereoselective selenenylation reactions of various alkenes. Different cleavage protocols allow further functionalization of the addition products leading to improvements in selenium-based solid-phase chemistry. 相似文献
8.
Some chemical transformations in the series of the pyrrolo [3,2-b]azepines and the pyrrolo[3,2-c]azepines are reported: alkylation at the pyrrolo nitrogen and/or the azepino nitrogen, reduction of the lactam group by means of LiAlH4, preparation of lactim ethers and amidines, substitution in position 2 by MANNICH reaction, bromination and condensation with oxalyl chloride or chloral hydrate, and the cyclocondensation with dimethylmalonyl chloride. The structures of the 2-substitution products have been evaluated by NMR.-spectroscopy. 相似文献
9.
Armbruster P Agarwal YK Brüchle W Brügger M Dufour JP Gaggeler H Hessberger FP Hofmann S Lemmertz P Münzenberg G Poppensieker K Reisdorf W Schadel M Schmidt K Schneider JH Schneider WF Sümmerer K Vermeulen D Wirth aG Ghiorso A Gregorich KE Lee D Leino M Moody KJ Seaborg GT Welch RB Wilmarth P Yashita S Frink C Greulich N Herrmann G Hickmann U Hildebrand N Kratz JV Trautman N Fowler MM Hoffman DC Daniels WR von Gunten HR Dornhöfer H 《Physical review letters》1985,54(5):406-409
10.
Recently, we described the establishment of a computerized database of rat liver epithelial (RLE) cellular polypeptides (Wirth et al., Electrophoresis, 1991, 12, 931-954). This database has now been expanded to include the analysis of cellular polypeptide alterations during chemically (aflatoxin B1; AFB), spontaneously, and oncogene (v-Ha-ras, v-raf, and v-myc/v-raf)-induced transformation of RLE cells. Two-dimensional mapping of [35S]methionine-labeled whole cell lysate, cell-free in vitro translation products and [32P]orthophosphate-labeled polypeptides revealed subsets of polypeptides specific for each transformation modality. A search of the RLE protein database indicated the specific subcellular location for the majority of these transformation-sensitive proteins. Significant alterations in the expression of the extracellular matrix protein, fibronectin, as well as tropomyosin- and intermediate filament-related polypeptides (vimentin, beta-tubulin, the cytokeratins, and actin) were observed among the various transformant cell lines. Immunoprecipitation and Western immunoblot analysis of tropomyosin expression in four individual AFB-, as well as four spontaneously induced, and each of the oncogene-transformed cell lines indicated that five major tropomyosin (Tm 1-5) isoforms were variably expressed in the various cell lines, including one polypeptide tentatively identified as Tm6. Whereas alterations in tropomyosin expression appeared to be transformation-specific, alterations in the individual intermediate filament polypeptides were related more to the differentiation state of the individual cell lines rather than to the transformation phenotype. These studies extend our earlier efforts toward the establishment of a comprehensive computerized database of RLE cellular proteins and demonstrates how such a database may serve as a useful source for studies concerning the regulation of growth and differentiation as well as transformation of RLE cells. 相似文献