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141.
An important goal of spray cooling research is the ability to predict local heat transfer from the spray hydrodynamics. It is postulated that the local normal pressure exerted by the spray onto the heated surface can be used to obtain the local heat transfer coefficient. This hypothesis was tested using data obtained from hollow cone, full cone, and linear sprays at four nozzle pressures and three stand-off distances. A correlation between the pressure and heat transfer coefficient was determined from the data, then used to “predict” the heat transfer coefficient to verify the accuracy of the correlation. The area averaged heat transfer coefficient could be predicted within 25%, indicating that pressure can be used to predict the local heat transfer coefficient in the single-phase regime. 相似文献
142.
143.
Together with detection and use of protective clothing, decontamination is the third important part in NBC defence and NBC protection. Enzymes play an important role in the research field of new and environmentally friendly decontaminants. In 1946, organophosphate cleaving enzymes were first mentioned, and in the next decades further enzymes (i.e., DFPase) against G‐type nerve agents were discovered. After the cloning of the DFPase gene sequence in the 90s, the potential of DFPase as an environmentally friendly decontaminant was shown. In technical decontamination experiments, it was shown that the conditions for an enzyme‐based decontamination concept could be met for one class of chemical agents. However, the success of a general enzyme decontamination concept depends on the discovery of new enzymes against other classes of chemical agents, i.e., mustard and VX. 相似文献
144.
Celest Samyn Goedele Claes Marcel van Beylen Anneleen De Wachter Andre Persoons 《Macromolecular Symposia》1996,102(1):145-158
The synthesis and second harmonic coefficients, d3,1 and d3,3 as well as the related susceptibilities χ(2)zzz of five series of (NLO-dye methacrylate)-(methyl methacrylate) copolymers were investigated. The NLO-chromophores bound covalently to the polymer backbone were 5-(2,2-dicyanovinyl)-or 4-(2-cyano-2-methoxycarbonyl)vinyl-1-piperidino-2-thiophene (P1 and P2), 4-nitro-4′-alkoxy-stilbene (P3), 4-nitro-3′-methoxy-4′-alkoxystilbene (P4) and 4-nitro-4′-alkoxy-α-cyano stilbene (P5). The second order nonlinear optical properties of corona-poled aligned thin polymer films, using a needle electrode in order to induce noncentrosymmetry, were evaluated. Nonlinear susceptibilities, χ(2)zzz, of the films were derived from the analysis of full-angle Maker fringe patterns at 1064 nm, χ(2)zzz values as high as 1.98×10−7 esu for P2 copolymers and of 1.19×10−7 esu for P3 copolymers could be achieved. 相似文献
145.
Andre Laestadius Michael Benedicks Markus Penz 《International journal of quantum chemistry》2020,120(8):e26149
The unique-continuation property from sets of positive measure is here proven for the many-body magnetic Schrödinger equation. This property guarantees that if a solution of the Schrödinger equation vanishes on a set of positive measure, then it is identically zero. We explicitly consider potentials written as sums of either one-body or two-body functions, typical for Hamiltonians in many-body quantum mechanics. As a special case, we are able to treat atomic and molecular Hamiltonians. The unique-continuation property plays an important role in density-functional theories, which underpins its relevance in quantum chemistry. 相似文献
146.
Qusai Hassan Rudraksha Dutta Majumdar Bing Wu Daniel Lane Maryam Tabatabaei-Anraki Ronald Soong Myrna J. Simpson Andre J. Simpson 《Magnetic resonance in chemistry : MRC》2019,57(2-3):69-81
Proton nuclear magnetic resonance (NMR) spectra of intact biological samples often show strong contributions from lipids, which overlap with signals of interest from small metabolites. Pioneering work by Diserens et al. demonstrated that the relative differences in diffusivity and relaxation of lipids versus small metabolites could be exploited to suppress lipid signals, in high-resolution magic angle spinning (HR-MAS) NMR spectroscopy. In solution-state NMR, suspended samples can exhibit very broad water signals, which are challenging to suppress. Here, improved water suppression is incorporated into the sequence, and the Carr-Purcell-Meiboom-Gill sequence (CPMG) train is replaced with a low-power adiabatic spinlock that reduces heating and spectral artefacts seen with longer CPMG filters. The result is a robust sequence that works well in both HR-MAS as well as static solution-state samples. Applications are also extended to include in vivo organisms. For solution-state NMR, samples containing significant amount of fats such as milk and hemp hearts seeds are used to demonstrate the technique. For HR-MAS, living earthworms (Eisenia fetida) and freshwater shrimp (Hyalella azteca) are used for in vivo applications. Lipid suppression techniques are essential for non-invasive NMR-based analysis of biological samples with a high-lipid content and adds to the suite of experiments advantageous for in vivo environmental metabolomics. 相似文献
147.
Nonlinear Dynamics - In general, the mechanisms that maintain the activity of neural systems after a triggering stimulus has been removed are not well understood. Different mechanisms involving at... 相似文献
148.
A. David McDonald Anthony D.M. Smith Andre E. Punt Geoffrey N. Tuck Adam J. Davidson 《Natural Resource Modeling》1997,10(1):3-29
An approach to incorporating new information using Bayes' theorem is applied to obtain estimates of expected returns from research on stock structure for determination of total allowable catch (TAC). Expected returns are measured relative to quantitative performance criteria that are inferred from fishery management objectives. Principles of the approach are outlined and a detailed case study of Tasmanian orange roughy is reported. 相似文献
149.
Dimitra Markovitsi Jean-Jacques Andre André Mathis Jacques Simon Pierre Spegt Gilbert Weill Martine Ziliox 《Chemical physics letters》1984,104(1):46-49
The solid—solid phase transition of an annlide type copper complex are described. As the temperature is raised, three different constituents of the complex successively melt. In the temperature range 77–95°C, the polyethylene oxide chains and the paraffinic tail are both in a very mobile state while the copper complex sub-units still form a two-dimensional crystalline array. 相似文献
150.
A new lattice model of interacting electrons is presented. It can be viewed as a classical Hubbard model in which the energy associated to electron itinerance is proportional to the total number of possible electron jumps. Symmetry properties of the Hubbard model are preserved. In the half-filled band with strong interaction the model becomes the Ising model. The main features of the magnetic behavior of the model in the one-dimensional and mean-field cases are studied. 相似文献