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111.
E. Wierzbicki Cz. Woźniak L. Łacińska 《Archive of Applied Mechanics (Ingenieur Archiv)》2005,74(9):618-628
Two problems will be studied in this contribution. First, we analyse some phenomena which take place in a laminated solid and are caused by a fluctuation of time-dependent boundary tractions. Second, we investigate the transient effect of initial displacement fluctuations on the behaviour of a laminate. To solve the above problems we propose a new macroscopic 3D model for investigations of initial-boundary value problems in elastodynamics of a laminated medium. 相似文献
112.
1,3-Dipolar cycloaddition of alkyl glyoxylate-derived nitrones to E-crotonaldehyde can be catalyzed by hybrid diamines, obtained from (S)-BINAM and l-α-amino acids. The hybrid of (S)-BINAM and l-Phe was found to be the best organocatalyst. Products were obtained in good yield and diastereoselectivity as well as high enantioselectivity (82-91% ee). Subsequent transformations into functionalized pyrrolidinones have been demonstrated. 相似文献
113.
114.
Pokrzywnicka M Cocovi-Solberg DJ Miró M Cerdà V Koncki R Tymecki Ł 《Analytical and bioanalytical chemistry》2011,399(3):1381-1387
A cost-effective, highly compact, and versatile optoelectronic device constructed of two ordinary light emitting diodes compatible
with optosensing films has been developed. This fibreless device containing chemoreceptor, semiconductor light source, and
detector integrated in a miniaturized flow-through cell of low microliter internal volume works as a complete photometric
chemical sensor suitable for detection in flow analysis. The operation of the developed device under nonstationary programmable-flow
conditions offered by sequential injection analysis has been demonstrated using Prussian Blue film as a model optical chemoreceptor.
The unique spectroelectrochemical properties of the sensing material enable its use for optical sensing of redox species,
whereby ascorbic acid and hydrogen peroxide have been chosen as model analytes. The reported SI-sensor system features fast
and reproducible determination of both analytes in the submillimolar range of concentrations. The construction concept demonstrated
in this work can be easily applied to other kinds of optical sensors based on absorbance sensing films. 相似文献
115.
Two ordinary green light-emitting diodes used as light emitter and detector coupled with simple voltmeter form a complete,
cost-effective prototype of a photometric hemoglobinometer. The device has been optimized for cuvette assays of total hemoglobin
(Hb) in diluted blood using three different chemical methods recommended for the needs of clinical analysis (namely Drabkin,
lauryl sulfate, and dithionite methods). The utility of developed device for real analytics has been validated by the assays
of total Hb content in human blood. The results of analysis are fully compatible with those obtained using clinically recommended
method and clinical analyzer. 相似文献
116.
In the present paper, we obtain new results on universality as applications of hybrid universality and almost-periodicity in its half-plane of absolute convergence. By using these, we show the universality for Euler products of Igusa type, Euler-Zagier multiple zeta-functions and Tornheim-Hurwitz type of double zeta-functions. 相似文献
117.
Zbigniew Pucha?a Piotr Gawron ?ukasz Skowronek Karol ?yczkowski 《Linear algebra and its applications》2011,434(1):327-342
We study operators acting on a tensor product Hilbert space and investigate their product numerical range, product numerical radius and separable numerical range. Concrete bounds for the product numerical range for Hermitian operators are derived. Product numerical range of a non-Hermitian operator forms a subset of the standard numerical range containing the barycenter of the spectrum. While the latter set is convex, the product range needs not to be convex nor simply connected. The product numerical range of a tensor product is equal to the Minkowski product of numerical ranges of individual factors. 相似文献
118.
Albrecht Ł Jiang H Jørgensen KA 《Angewandte Chemie (International ed. in English)》2011,50(37):8492-8509
Asymmetric organocatalysis has been successfully incorporated in many multistep one-pot sequences to provide simple access to structurally complex target molecules in a highly stereoselective fashion. The key feature behind this success is the ability of organocatalyzed reactions to proceed efficiently in the presence of large amounts of spectator reagents. Additionally, owing to their organic nature and substoichiometric presence, organocatalysts are also expected to become innocent bystanders in subsequent transformations. In this Minireview, an easy-to-use classification and nomenclatural system that is capable of systematically and informatively describing each one-pot reaction is introduced, and selected important contributions within the field of organocatalytic one-pot reactions are reviewed according to this new system. Finally, future developments and perspectives in the field are discussed. 相似文献
119.
Dr. Iwona Olejniczak Dr. Andrzej Łapiński Prof. Roman Świetlik Dr. Jean Olivier Dr. Stéphane Golhen Dr. Lahcène Ouahab 《Chemphyschem》2011,12(11):2124-2130
The room‐temperature infrared and Raman spectra of a series of four isostructural polymeric salts of 2,3,6,7‐tetrakis(2‐cyanoethylthio)‐tetrathiafulvalene (TCE‐TTF) with paramagnetic (CoII, MnII) and diamagnetic (ZnII, CdII) ions, together with BF4? or ClO4? anions are reported. Infrared and Raman‐active modes are identified and assigned based on theoretical calculations for neutral and ionized TCE‐TTF using density functional theory (DFT) methods. It is confirmed that the TCE‐TTF molecules in all the materials investigated are fully ionized and interact in the crystal structure through cyanoethylthio groups. The vibrational modes related to the C?C stretching vibrations of TCE‐TTF are analyzed assuming the occurrence of electron–molecular vibration coupling (EMV). The presence of the antisymmetric C?C dimeric mode provides evidence that charge transfer takes place between TCE‐TTF molecules belonging to neighboring polymeric networks. 相似文献
120.
Łukasz Kosiński 《Journal of Geometric Analysis》2011,21(4):902-919
We give a characterization of non-hyperbolic pseudoconvex Reinhardt domains in ℂ2 for which the answer to the Serre problem is positive. Moreover, all non-hyperbolic pseudoconvex Reinhardt domains in ℂ2 with non-compact automorphism group are explicitly described. 相似文献