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101.
Marina V. Tvalavadze 《代数通讯》2013,41(8):2816-2837
We study the universal enveloping algebras of the one-parameter family of solvable 5-dimensional non-Lie Malcev algebras. We explicitly determine the universal nonassociative enveloping algebras (in the sense of Pérez-Izquierdo and Shestakov) and the centers of the universal enveloping algebras. We also determine the universal alternative enveloping algebras. 相似文献
102.
Stephen A. Clark 《Positivity》2006,10(3):475-489
The existence of a feasible solution to a system of infinite-dimensional linear inequalities is characterized by a topological
generalization of the Farkas Condition. If this result is specialized to a finite-dimensional vector space with finite positive
cone, then a geometric proof of the classic Minkowski-Farkas Lemma is obtained. A dual version leads to an infinite-dimensional
extension of the Theorem of the Alternative. 相似文献
103.
Absolute valued triple system are the natural ternary extension of absolute valued algebras. In this article we classify strongly power-associative absolute valued triple systems. 相似文献
104.
The present work investigated the effects of sonication at different amplitudes and durations on the in vitro digestibility of buckwheat protein isolates (BPIs). The conformation, particle size and microstructures of the BPIs were also studied to explicate the possible mechanisms of the sonication-induced changes. The results showed that sonication conditions of 20 kHz, pulsed on-time 10 s, off-time 5 s, amplitude of 60% and duration of 10 min (SA6T10) improved the digestibility of BPIs from 41.4% (control) to 58.2%. The tertiary structure analysis showed that sonication exposed the hydrophobic core buried inside the protein molecules and broke the intramolecular crosslinks, based on the increase in the surface hydrophobicity and intrinsic fluorescence and the decrease in the disulphide content. The secondary structure analysis showed that SA6T10 decreased the content of β-turn and β-sheet by 40.9% and 22.4%, respectively, and increased the content of anti-parallel β-sheet, random coil, and α-helix by 40.9%, 30.6%, and 25.5%, respectively. The particle size of the control BPIs (427.7 ± 76.7 nm) increased to 2130.8 ± 356.2 nm in the SA6T10 sonicated sample with a corresponding decrease in the polydispersity index from 0.97 ± 0.04 to 0.51 ± 0.13. Moreover, scanning electron microscopy indicated that sonication broke the macroparticles into smaller fragments and changed the surface state of the proteins. Taken together, sonication has proven to be a promising approach for improving the digestibility of buckwheat proteins, which can be explored as a source of plant-based alternative protein for food applications. 相似文献
105.
Shigui?RuanEmail author Weinian?Zhang 《Journal of Dynamics and Differential Equations》2005,17(4):759-777
In this paper we investigate the transversality of homoclinic orbits in partial functional differential equations. We first
discuss the exponential dichotomies for linear operator equations. Then we show that the Fredholm Alternative holds if the
homogeneous equation has exponential dichotomies on R. Transversality of homoclinic orbits for periodically perturbed partial functional differential equations is studied using
the Liapunov-Schmidt method and the Melnikov integral.
Ams Subject Classifications: 35R10; 58F14. 相似文献
106.
GC-MS与交互移动窗口因子分析法(AMWFA)用于3种陈皮挥发油成分的比较分析 总被引:14,自引:0,他引:14
将GC-MS法与新近提出的用于二维数据比较和解析的交互移动窗口因子分析法(AMWFA)结合, 对3种不同原植物来源的陈皮挥发油成分的共性和差异性进行分析, 并对重叠峰进行解析, 总共分辨出138个峰, 定性出78个峰, 其中共有组分44个. 相似文献
107.
Margarita Stoytcheva Roumen Zlatev Zdravka Velkova Velizar Gochev Alan Ayala Gisela Montero Benjamín Valdez 《Electroanalysis》2019,31(4):652-660
The high resolution second order voltammetric technique, Differential Alternative Pulse Voltammetry (DAPV), was applied for the simultaneous quantification of the mononitrophenol (NP) isomers. Complete resolution of the three isomers was achieved at concentration ratios as high as 1 : 5, employing the corresponding anodic and cathodic peaks appeared on the DAPV curve. The working glassy carbon electrode was modified by a nanocomposite of graphite nanopowder and Au nanoparticles to increase the sensitivity. The linear concentration range was found to be extended up to 125 μmol L?1 for both the m‐NP and p‐NP isomers, while the o‐NP isomer presented calibration plot of two linear sections: up to 100 μmol L?1 and up to 225 μmol L?1. The LOD was found to be as low as 1.5 μmol L?1, 2.5 μmol L?1, and 0.5 μmol L?1 for o‐NP, m‐NP, and p‐NP, respectively. The accuracy of the proposed method was evaluated by quantification of spiked tap waters samples. No interference was observed from a range of phenolic compounds such as phenol, 4‐aminophenol, 4‐chlorophenol, 2,4‐dinitrophenol, and resorcinol. 相似文献
108.
Rodrigo Amorim Bezerra da Silva Adriano César Rabelo Rodrigo Alejandro Abarza Munoz Eduardo Mathias Richter 《Electroanalysis》2010,22(19):2167-2171
This work describes the construction, characterization, and application of a three‐electrode‐integrated sensor into a micropipette tip. The three electrodes (working, pseudoreference and counter) are positioned at the end of a micropipette tip. The working electrode (graphite composite or gold microfiber) is placed inside the micropipette tip and the pseudo‐reference and counter electrodes outside (diametrically opposed sides). This approach is candidate for portable applications and allows the analysis and studies in low‐volume solutions (ca. 10 µL) which are useful for waste minimization and development of clean analytical methods. In addition, the three‐electrode‐integrated sensor can be easy used as detector in flow injection system through its direct joining at the end of polyethylene tubing of the FIA system. 相似文献
109.
Jiřrina Scholtzová 《代数通讯》2013,41(1):96-107
A base of the free alternative nil-superalgebra of index n, for n ≥ 3, on one odd generator is constructed. In particular, its index of solvability is computed. As a corollary over a field of characteristic zero an infinite family of solvable alternative algebras which are not associative of arbitrary big solvability index with explicit multiplication table is obtained. 相似文献
110.
The interaction of quercetin-Cu(II) complex with calf thymus DNA was investigated with the use of Neutral Red (NR) dye as a spectral probe by the application of UV-vis spectrophotometry, cyclic voltammetry and synchronous fluorescence spectroscopy. The results showed that both quercetin-Cu(II) complex and the NR molecule can intercalate into the double helix of the DNA. The 2:1 quercetin:Cu(II) complex (estimated binding constant = 2.85 × 109) is stabilized by intercalation in the DNA (binding constant, K[quercetin-Cu(II)-DNA] = (1.82 ± 0.20) × 105 M−1), and displaces the NR dye from the NR-DNA complex in a competitive reaction. Cyclic voltammetry studies confirm the intercalation reaction and show that the ratio (KR/KO) of binding constants for the reduced and oxidized forms of the metal complex is 2.05. Furthermore, the alternative least squares (ALS) method was applied to resolve a complex two-way array of the absorption spectra data. This yielded the equilibrium concentration profiles of each component in the reaction (NR, NR-DNA and quercetin-Cu(II)) as well as the corresponding pure spectra. The extracted profiles showed that at equilibrium the [NR-DNA] and [NR] trends decreased and increased symmetrically, respectively, with approximately linear behaviour being observed below 10 × 10−6 mol L−1 of the added quercetin-Cu2+ complex. Thereafter, these trends converged asymptotically. The free [quercetin-Cu(II)] trend-line at equilibrium was linear over the whole range of the complex added. It was possible to estimate the approximate value of the equilibrium constant of the exchange process (approximately 5 × 10−1) involving the intercalation of the quercetin-Cu(II) complex. It was also found that about 35% of the bound complex was unaccounted by the intercalation reaction, presumably being stabilized at an alternative site. 相似文献