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51.
The exotic bialgebras that arise from a 9 × 9 unitary braid matrix are constructed. The dual bialgebra of one of these exotic bialgebras is presented. 相似文献
52.
Given a sequence A=(A1,…,Ar) of binary d-ics, we construct a set of combinants C={Cq:0≤q≤r,q≠1}, to be called the Wronskian combinants of A. We show that the span of A can be recovered from C as the solution space of an SL(2)-invariant differential equation. The Wronskian combinants define a projective imbedding of the Grassmannian G(r,Sd), and, as a corollary, any other combinant of A is expressible as a compound transvectant in C.Our main result characterises those sequences of binary forms that can arise as Wronskian combinants; namely, they are the ones such that the associated differential equation has the maximal number of linearly independent polynomial solutions. Along the way we deduce some identities which relate Wronskians to transvectants. We also calculate compound transvectant formulae for C in the case r=3. 相似文献
53.
Abdoullah Bimoussa Yassine Koumya Abdesselam Abouelfida Moulay Youssef Ait Itto Abdelaziz Benyaich Olivier Mentre El Mostafa Ketatni Aziz Auhmani Abdelwahed Auhmani 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(6):623-632
Treatment of thiosemicarbazones prepared from sesquiterpenes with ethyl 2‐bromoacetate in the presence of sodium acetate afforded the corresponding thiazolidin‐4‐ones. The structures of all the newly synthesized compounds were established by considering spectral and single‐crystal X‐ray diffraction data. The title compound, ethyl 2‐((Z)‐2‐{(Z)‐[(1aR,5aR,9aS)‐1,1‐dichloro‐1a,5,5,7‐tetramethyl‐1a,2,3,4,5,5a,8,9‐octahydro‐1H‐benzo[a]cyclopropa[b][7]annulen‐8‐ylidene]hydrazono}‐4‐oxothiazolidin‐3‐yl)acetate, C23H31Cl2N3O3S, 5 , crystallizes in the orthorhombic noncentrosymmetric space group P212121 with Z = 4. Within the molecule in the crystal structure, the cyclohexene ring has an envelope conformation and the cycloheptane ring, to which it is fused, has a boat conformation. In the crystal, molecules are linked by C—H…Cl hydrogen bonds forming chains propagating along the b‐axis direction. The absolute configuration of the molecule in the crystal could be fully confirmed from anomalous dispersion effects [Flack parameter = ?0.04 (2)]. Thiosemicarbazones 1 and 2 are efficient inhibitors for steel corrosion in 1 M H2SO4 solution, with a maximum efficiency of 92.28% at 10?3 M. Furthermore, thiosemicarbazone compounds were found to be more efficient than thiazolidin‐4‐one derivatives. In addition, cyclic voltammetry was used to characterize the tested molecules, as well to estimate the experimental value of the energy band gap. 相似文献
54.
B. Briat M. T. Borowiec H. Bou Rjeily F. Ramaz A. Hamri H. Szymczak 《辐射效应与固体损伤》2013,168(6-12):989-993
Electron paramagnetic resonance is detected optically via the change of magnetic circular dichroism under microwaves at 35 v GHz. The technique is applied to Bi 12 GeO 20 samples co-doped with vanadium and a second transition metal (Cr, Mn, Co, Cu). The optical and magnetic properties of several paramagnetic defects (V Ge 4+ and Cr Ge 4+ ) are directly correlated. The basic photochromic processes occuring in samples doped with V, Mn, and Mn+V are explained. The V Ge 4+/5+ level is positioned roughly 2.2 v eV above the valence band. 相似文献
55.
Abazov VM Abbott B Abdesselam A Abolins M Abramov V Acharya BS Adams DL Adams M Ahmed SN Alexeev GD Alton A Alves GA Amos N Anderson EW Arnoud Y Avila C Baarmand MM Babintsev VV Babukhadia L Bacon TC Baden A Baldin B Balm PW Banerjee S Barberis E Baringer P Barreto J Bartlett JF Bassler U Bauer D Bean A Beaudette F Begel M Belyaev A Beri SB Bernardi G Bertram I Besson A Beuselinck R Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Blazey G Blekman F Blessing S Boehnlein A Bojko NI Borcherding F 《Physical review letters》2002,88(19):191801
We present the results of a search for leptoquark (LQ) pairs in (85.2+/-3.7) pb(-1) of pp* collider data collected by the D0 experiment at the Fermilab Tevatron. We observe no evidence for leptoquark production and set a limit on sigma(pp*-->LQLQ-->nunu+jets) as a function of the mass of the leptoquark (m(LQ)). Assuming the decay LQ-->nuq, we exclude scalar leptoquarks for m(LQ) < 98 GeV/c(2), and vector leptoquarks for m(LQ) < 200 GeV/c(2) and coupling which produces the minimum cross section, at a 95% confidence level. 相似文献
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57.
James Neeway Abdesselam Abdelouas Bernd Grambow Stéphan Schumacher Christelle Martin Masashi Kogawa Satoshi Utsunomiya Stéphane Gin Pierre Frugier 《Journal of Non》2012,358(21):2894-2905
Corrosion of nuclear waste glass in unsaturated conditions is expected to occur upon the closure of the repository galleries during disposal cell saturation in the proposed French disposal site. The objectives of the present work were to determine the alteration kinetics of the SON68 reference in such conditions. Vapor hydration tests were conducted using thin, polished SON68 glass coupons contained in stainless steel autoclaves. Temperatures ranged between 90 °C and 200 °C and the relative humidity (RH) was maintained at 91 ± 1%. Additional experiments at 175 °C and 80, 85, 90 and 95% RH were also conducted to assess the role of RH on the glass corrosion rate. The nature and extent of corrosion have been determined by characterizing the reacted glass surface with scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDS). Elemental profiling of the glass hydrated at 90 °C was studied by TOF-SIMS. The chemical composition of the external layer depends on experimental conditions. The hydration rate at 90 °C (TOF-SIMS analysis) is 10 × higher than the generally accepted final rate of SON68 in water at 90 °C (~ 10? 4 g m? 2 d? 1). This may indicate that the glass hydration process cannot be simulated by experiments in aqueous solution with a high S/V ratio. Subsequent leaching (corrosion in an aqueous solution) of samples weathered in water vapor showed dissolution rate values higher than those of pristine glass. This result indicates that mobile elements are trapped within the alteration products during the hydration step and it gives insight into mobility variations of the considered elements. 相似文献
58.
Salha Hamri Jose Rodríguez Joan Basset Gérald Guillaumet M. Dolors Pujol 《Tetrahedron》2012,68(31):6269-6275
We report a direct iodination of indole and derivative compounds with iodine monochloride (ICl) in the presence of Celite®. This procedure has now been extended to the iodination of substituted indoles, azaindoles and pyrroles. The scope of this procedure is exemplified by the iodination of melatonin in 98% yield. 相似文献