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61.
Solution densities over the temperature range 288.15 to 328.15 K have been measured for aqueous solutions of N-acetylarginamide monotrifluoroacetate and sodium trifluoroacetate, from which the partial molar volumes at infinite dilution,
V2oV_{2}^{\mathrm{o}}, were determined. The partial molar heat capacities at infinite dilution, Cp,2oC_{p,2}^{\mathrm{o}}, were also determined for these solutes over the same temperature range. These V2oV_{2}^{\mathrm{o}} and Cp,2oC_{p,2}^{\mathrm{o}} results, along with relevant data taken from the literature, have been used to calculate the contributions of the protonated
arginyl side-chain to the thermodynamic properties. These new side-chain values were critically compared with those obtained
previously using alternative side-chain model compounds. 相似文献
62.
Good K Kuksenok O Buxton GA Ginzburg VV Balazs AC 《The Journal of chemical physics》2004,121(12):6052-6063
We investigate the structural evolution of an A/B/C ternary mixture in which the A and B components can undergo a reversible chemical reaction to form C. We developed a lattice Boltzmann model for this ternary mixture that allows us to capture both the reaction kinetics and the hydrodynamic interactions within the system. We use this model to study a specific reactive mixture in which C acts as a surfactant, i.e., the formation of C at the A/B interface decreases the interfacial tension between the A and B domains. We found that the dynamics of the system is different for fluids in the diffusive and viscous regimes. In the diffusive regime, the formation of a layer of C at the interface leads to a freezing of the structural evolution in the fluid; the values of the reaction rate constants determine the characteristic domain size in the system. In the viscous regime, where hydrodynamic interactions are important, interfacial reactions cause a slowing down of the domain growth, but do not arrest the evolution of the mixture. The results provide guidelines for controlling the morphology of this complex ternary fluid. 相似文献
63.
Gavin D. Henry Author Vitae 《Tetrahedron》2004,60(29):6043-6061
64.
Maspoch D Domingo N Ruiz-Molina D Wurst K Hernández JM Vaughan G Rovira C Lloret F Tejada J Veciana J 《Chemical communications (Cambridge, England)》2005,(40):5035-5037
A metal-organic open-framework with an unprecedented (6,3)-helical topology, large channels and mixed ferro- and antiferromagnetic interactions has been synthesized using a three-connecting tricarboxylic polychlorotriphenylmethyl radical and Co(ii) ions. 相似文献
65.
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67.
S. Gavin H. Satz R. L. Thews R. Vogt 《Zeitschrift fur Physik C Particles and Fields》1994,63(2):351-355
It is shown that the scattering amplitudes of some degenerate massive string states can be expressed in terms of that of higher spin states at the same mass level. This phenomenon is discussed from σ-model point of view and demonstrated explicitly by using massive Ward identities generated by zero-norm states atD=26. The subtlety of the scalar propagating state is briefly pointed out. We also compare our on-shell gauge symmetry derived from σ-model with off-shell gauge symmetry of covariant string field theory. 相似文献
68.
Björn Bohman Gavin R. Flematti Russell A. Barrow 《Journal of mass spectrometry : JMS》2015,50(8):987-993
Pyrazines are well‐known natural products that are present in bacterial odours and food flavouring agents and are used as insect pheromones. Recently, a number of hydroxymethylpyrazines have been identified as thynnine wasp pheromones and orchid semiochemicals that are essential for pollination in sexually deceptive plants. These compounds are present in low amounts in complex blends, making GC–MS (including high‐resolution techniques) the method of choice for their structure elucidation. We report the EI mass spectra for 14 representative compounds and have found that based on characteristic fragmentations, it is possible to distinguish between different positional isomers of hydroxymethylpyrazines. The presence or absence of either [M ? 17]+, [M ? 18]+· or [M ? 19]+ fragment species provides characteristic information to allow the distinction between the different isomers. Considering the importance of pyrazines as a group of bioactive natural products, and the recent findings of biological activity for hydroxymethylpyrazines, our results presented here will aid the identification of these compounds in other biological systems. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
69.
Regan J. Anderson Benjamin J. Compton Ching-wen Tang Astrid Authier-Hall Colin M. Hayman Gene W. Swinerd Renata Kowalczyk Paul Harris Margaret A. Brimble David S. Larsen Olivier Gasser Robert Weinkove Ian F. Hermans Gavin F. Painter 《Chemical science》2015,6(9):5120-5127
It is known that T cells can eliminate tumour cells through recognition of unique or aberrantly expressed antigens presented as peptide epitopes by major histocompatibility complex (MHC) molecules on the tumour cell surface. With recent advances in defining tumour-associated antigens, it should now be possible to devise therapeutic vaccines that expand specific populations of anti-tumour T cells. However there remains a need to develop simpler efficacious synthetic vaccines that possess clinical utility. We present here the synthesis and analysis of vaccines based on conjugation of MHC-binding peptide epitopes to α-galactosylceramide, a glycolipid presented by the nonpolymorphic antigen-presenting molecule CD1d to provoke the stimulatory activity of type I natural killer T (NKT) cells. The chemical design incorporates an enzymatically cleavable linker that effects controlled release of the active components in vivo. Chemical and biological analysis of different linkages with different enzymatic targets enabled selection of a synthetic vaccine construct with potent therapeutic anti-tumour activity in mice, and marked in vitro activity in human blood. 相似文献
70.