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101.
Naihong Hu Yufeng Pei Dong Liu 《Proceedings of the American Mathematical Society》2008,136(2):437-447
Mainly motivated by Pirashvili's spectral sequences on a Leibniz algebra, a cohomological characterization of Leibniz central extensions of Lie algebras is given. In particular, as applications, we obtain the cohomological version of Gao's main theorem for Kac-Moody algebras and answer a question in an earlier paper by Liu and Hu (2004).
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103.
Radu Ioan Bo? Sorin-Mihai Grad 《Journal of Mathematical Analysis and Applications》2008,337(2):1315-1325
We give some necessary and sufficient conditions which completely characterize the strong and total Lagrange duality, respectively, for convex optimization problems in separated locally convex spaces. We also prove similar statements for the problems obtained by perturbing the objective functions of the primal problems by arbitrary linear functionals. In the particular case when we deal with convex optimization problems having infinitely many convex inequalities as constraints the conditions we work with turn into the so-called Farkas-Minkowski and locally Farkas-Minkowski conditions for systems of convex inequalities, recently used in the literature. Moreover, we show that our new results extend some existing ones in the literature. 相似文献
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Gert Vegter. 《Mathematics of Computation》2000,69(230):691-720
Some recent methods of Computer Aided Geometric Design are related to the apolar bilinear form, an inner product on the space of homogeneous multivariate polynomials of a fixed degree, already known in 19th century invariant theory. Using a generalized version of this inner product, we derive in a straightforward way some of the recent results in CAGD, like Marsden's identity, the expression for the de Boor-Fix functionals, and recursion schemes for the computation of B-patches and their derivatives.
106.
《中国物理 B》2021,30(9):96802-096802
We perform first principles calculations to investigate the catalytic behavior of C_9 N_4 nanosheet for water splitting.For the pristine C_9 N_4,we find that,at different hydrogen coverages,two H atoms adsorbed on the 12-membered ring and one H atom adsorbed on the 9-membered ring show excellent performance of hydrogen evolution reaction(HER).Tensile strain could improve the catalytic ability of C_9 N_4 and strain can be practically introduced by building C_9 N_4/BiN,and C_9 N_4/GaAs heterojunctions.We demonstrate that the HER performance of heterojunctions is indeed improved compared with that of C_9 N_4 nanosheet.Anchoring transition metal atoms on C_9 N_4 is another strategy to apply strain.It shows that Rh@C_9 N_4 exhibits superior HER property with very low Gibbs free energy change of-30 meV.Under tensile strain within ~2%,Rh@C_9 N_4 could catalyze HER readily.Moreover,the catalyst Rh_9 C_9 N_4 works well for oxygen evolution reaction(OER)with an overpotential of 0.58 V.Our results suggest that Rh@C_9 N_4 is favorable for both HER and OER because of its metallic conductivity,close-zero Gibbs free energy change,and low oneset overpotential.The outstanding performance of C_9 N_4 nanosheet could be attributed to the tunable porous structure and electronic structure compatibility. 相似文献
107.
Xiaoyong Chen Zeyu Zhang Jiajie Wu Jiale Wang Aolong Gao 《Particle & Particle Systems Characterization》2021,38(7):2100076
Red fluorescent carbon dots (R-CDs) are special desirable for biochemical analysis due to good biological compatibility and deep penetration; however, they remain as bottlenecks due to difficulties in expanding the sp2 domain, especially those are fused from rigid polycyclic conjugated molecules (RPCMs) with heteroatom substituents due to huge steric hindrance and heteroatom blockage toward graphic lattice. Here, an RPCM with heteroatom substituents, 1,5-diamino-4,8-dihydroxyanthraquinone (DDAQ), based self-doped R-CDs with PL emission at 635 nm is reported. Further investigations reveal that the expanding, hybrid sp2 domain with indanthrone tannin structure from DDAQ is mainly responsible for the obtained red fluorescence of R-CDs. Taking advantage of optical properties, R-CDs are considered to construct a colorimetric/fluorescent dual mode sensing array for quantifying trace levels of Fe3+ and glyphosate based on the static quenching, and a biomarker for cell imaging. The CD-based sensors exhibit outstanding recovery, high selectivity, and sensitivity, also facilitated dual-mode detection with the naked-eye. The R-CDs have low cytotoxicity, good cell membrane penetration for rapid cell entry, and high resolution, demonstrating their potential for biolabeling and bioanalytic applications. 相似文献
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