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921.
Zeily Nurachman Dewi Susan Brataningtyas Hartati Lily Maria Goretty Panggabean 《Applied biochemistry and biotechnology》2012,168(5):1065-1075
The potential of the tropical marine benthic-diatom Navicula sp. for biodiesel feedstock was investigated. Growth profiles were analyzed by changing nutrient compositions in three different media (Walne, plain seawater, and modified seawater) and irradiance intensities. Navicula sp. cells showed significant growth in Walne and modified seawater medium but not in plain seawater medium. The microalgae grew well in a pH range of 7.8?C8.4, and the cells were very sensitive to the intensity of direct sunlight exposure. The average cell concentration obtained from the cultures in plain seawater, Walne, and modified seawater media at the beginning of the stationary phase was 0.70, 2.17, and 2.54?g/L, respectively. Electron spray ionization-ion trap-mass spectrometry showed that the triacylglycerols of the algae oil were identified as POP (palmitic-oleic-palmitic), POO (palmitic-oleic-oleic), and OOLn (oleic-oleic-linoleic). The oil productivity of Navicula sp. cultivated in Walne and modified seawater media was 90 and 124???L?L?1 culture d?1. The Navicula sp. biodiesel exhibited a kinematic viscosity of 1.299?mm2/s, density of 0.8347?g/mL, and internal energy of 0.90?kJ/mL. 相似文献
922.
Giovanna Bonfanti Maria Grazia Naso 《Journal of Mathematical Analysis and Applications》2008,345(1):186-202
In this paper we analyze a dynamic unilateral contact problem between two thermoelastic beams. We establish the existence of a weak global-in-time solution, by a penalization method. Moreover, we study the asymptotic behavior of such a solution proving that the energy associated to the system decays exponentially to zero, as time goes to infinity. 相似文献
923.
924.
We consider the integral means for the class of functions which are meromorphic and univalent in an annulus. 相似文献
925.
The paper describes a new space of variable degree polynomials. This space is isomorphic to ℙ6, possesses a Bernstein like basis and has generalized tension properties in the sense that, for limit values of the degrees,
its functions approximate quadratic polynomials. The corresponding space of C
3, variable degree splines is also studied. This spline space can be profitably used in the construction of shape preserving
curves or surfaces.
AMS subject classification (2000) 65D07, 65D17, 65D10 相似文献
926.
Thomas Erker Maria E. Galanski Markus Galanski 《Journal of heterocyclic chemistry》2002,39(5):857-861
Some novel imidazolyl and pyrazolyl thiophene derivatives were synthesized. Different substituted N‐containing heterocycles were chosen with the aim of enhancing the activity or selectivity of the products towards inhibition of one of the three isoforms of nitric oxide synthase. One series of substances was prepared by substitution reactions of 3‐bromo‐2‐nitrothiophene with various heterocycles. In the other series introduction of a second heterocyclic substituent to pyrazolylthiophene compounds was attempted. 相似文献
927.
Gerd Teschke Mariya Zhariy Maria Joana Soares 《Mathematical Methods in the Applied Sciences》2008,31(5):575-587
We develop a regularization technique for Perona–Malik diffusion equations that relies on multiresolution techniques. The main result of this paper is to show that the chosen discretization overcomes the ill posedness of the nonlinear Perona–Malik model. The resulting algorithm is tested and the results are compared with pixel‐based methods. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
928.
929.
Vladimir I. Bregadze Andrey A. Semioshkin Julia N. Las'kova Maria Ya. Berzina Irina A. Lobanova Igor B. Sivaev Mikhail A. Grin Rustam A. Titeev Dmitry I. Brittal Olga V. Ulybina Anastasija V. Chestnova Anastasija A. Ignatova Alexey V. Feofanov Andrey F. Mironov 《应用有机金属化学》2009,23(9):370-374
Conjugates of chlorin e6 with closo‐dodecaborate and cobalt bis(dicarbollide) anions were synthesized for the first time in high yields using the advanced ‘click’ methodology. In vitro study on A549 human lung adenocarcinoma cells revealed that the synthesized boronated conjugates are able to penetrate and accumulate in cancer cells, but their intracellular concentration is not sufficient for effective photodynamic and boron neutron capture therapy of cancer. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
930.
Maria Luisa Dalla Chiara Roberto Giuntini Antonio Ledda Roberto Leporini Giuseppe Sergioli 《Foundations of Physics》2010,40(9-10):1494-1518
The characteristic holistic features of the quantum theoretic formalism and the intriguing notion of entanglement can be applied to a field that is far from microphysics: logical semantics. Quantum computational logics are new forms of quantum logic that have been suggested by the theory of quantum logical gates in quantum computation. In the standard semantics of these logics, sentences denote quantum information quantities: systems of qubits (quregisters) or, more generally, mixtures of quregisters (qumixes), while logical connectives are interpreted as special quantum logical gates (which have a characteristic reversible and dynamic behavior). In this framework, states of knowledge may be entangled, in such a way that our information about the whole determines our information about the parts; and the procedure cannot be, generally, inverted. In spite of its appealing properties, the standard version of the quantum computational semantics is strongly “Hilbert-space dependent”. This certainly represents a shortcoming for all applications, where real and complex numbers do not generally play any significant role (as happens, for instance, in the case of natural and of artistic languages). We propose an abstract version of quantum computational semantics, where abstract qumixes, quregisters and registers are identified with some special objects (not necessarily living in a Hilbert space), while gates are reversible functions that transform qumixes into qumixes. In this framework, one can give an abstract definition of the notions of superposition and of entangled pieces of information, quite independently of any numerical values. We investigate three different forms of abstract holistic quantum computational logic. 相似文献