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101.
In order to investigate the potential of thermal analysis for the determination of post-mortem age, rib bone specimens were collected from the remains of a number of slaughtered pigs that were allowed to decompose in the Australian bush in a controlled site under a range of conditions for time periods ranging from 1 to 5 years. The bone specimens were cut in cross-section with the compact bone collected for analysis. TG-MS curves were collected by heating bone samples to 1100°C in an argon atmosphere. The TG-MS data showed significant differences for the pig bone specimens derived from the different environments and showed trends in peak size correlating with age. The reported data suggest that TG-MS has significant potential for the identification of origin as well as the ageing of skeletal remains in a forensic context.  相似文献   
102.
The N-C coupling of ligating NO with 2-vinylpyridines, affording nitrosovinyl complexes, was found. This is of significance since the reaction process involves a C-H activation of the vinyl moiety and subsequent C-N bond formation. Furthermore, we show that the resulting nitrosovinyl complexes are chemically versatile and potentially valuable species. Protonation of the resulting nitrosovinyl complexes in refluxing alcohol afforded the alcohol-incorporated complexes, as well as the ketoimine species. It is interesting to note that a proton-induced reaction with PPh3 trapped their intermediates, leading to the explication of these reaction mechanisms.  相似文献   
103.
The physicochemical properties of room temperature ionic liquids (RTILs) consisting of bis(trifluoromethanesulfonyl)amide (TFSA) combined with 1-hexyl-1-methylpyrrolidinium (Pyr1,6+), 1-(butoxymethyl)-1-methylpyrrolidinium (Pyr1,1O4+), 1-(4-methoxybutyl)-1-methyl pyrrolidinium (Pyr1,4O1+), and 1-((2-methoxyethoxy)methyl)-1-methylpyrrolidinium (Pyr1,1O2O1+) were investigated using both experimental and computational approaches. Pyr1,1O2O1TFSA, which contains two ether oxygen atoms, showed the lowest viscosity, and the relationship between its physicochemical properties and the position and number of the ether oxygen atoms was discussed by a careful comparison with Pyr1,1O4TFSA and Pyr1,4O1TFSA. Ab initio calculations revealed the conformational flexibility of the side chain containing the ether oxygen atoms. In addition, molecular dynamics (MD) calculations suggested that the ion distributions have a significant impact on the transport properties. Furthermore, the coordination environments of the Li ions in the RTILs were evaluated using Raman spectroscopy, which was supported by MD calculations using 1000 ion pairs. The presented results will be valuable for the design of functionalized RTILs for various applications.  相似文献   
104.
105.
Radical polymerization of styrene derivatives having a series of amino acid, alanine, glycine, leucine, valine, Boc‐leucine, and Boc‐valine, in the side chain bound at the C‐terminal was conducted to regulate the stereoinduction system in the propagation step. Isotacticity increased in the polymer main chain, especially in the polymerization of monomers bearing N‐free L ‐leucyl and L ‐valyl esters in THF or DMF at 50 °C, by the synergic stereoregulation with chirality control and hydrogen bonding between the radical polymer terminal and the monomer. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010  相似文献   
106.
The MTV experiment (Mott Polarimetry for T-Violation Experiment) is running from 2009 at TRIUMF, which aims to search a large non-standard T-Violation in polarized nuclear beta decay. Existence of transverse polarization of electrons emitted from polarized 8Li nuclei, which are produced at TRIUMF-ISAC and stopped inside an aluminum stopper, is investigated. We utilize a Mott polarimeter consists of a planer drift chamber, measuring backward scattering left-right asymmetry from a thin lead analyzer foil. In this paper, preliminary results from the first physics run performed in 2010 are described.  相似文献   
107.
陈文清 《高分子科学》2010,28(4):527-535
<正>Polyvinylidene fluoride(PVDF) hollow fiber membranes prepared from spinning solutions with different polyvinyl pyrrolidone(PVP) contents(1%and 5%) at different extrusion rates were obtained by wet/dry phase process keeping all other spinning parameters constant.In spinning these PVDF hollow fibers,dimethylacetamide(DMAc) and PVP were used as a solvent and an additive,respectively.Water was used as the inner coagulant.Dimethylformamide(DMF) and water(30/70) were used as the external coagulant.The performances of membranes were characterized in terms of water flux,solute rejection for the wet membranes.The structure and morphology of PVDF hollow fiber were examined by BET adsorption,dry/wet weight method and scanning electron microscopy(SEM).It is found that the increase in PVP content and extrusion rate of spinning solution can result in the increase of water flux and decrease of solute rejection.The improvements of interconnected porous structure and pore size are induced by shear-thinning behavior of spinning solution at high extrusion rates,which could result in the increase of water flux of hollow fiber membranes.The increase of extrusion rate also leads to the increase of membrane thickness due to the recovery effect of elastic property of polymer chains.  相似文献   
108.
The ion transport facilitated by neutral carrier compounds (valinomycin, nonactin) has been investigated by cyclic voltammetry in the several electrolyte solutions (KF, KCl, KBr, KNO3, KSCN, KClO4), and we demonstrated the effect of the counter anions on the facilitated transport of K+ from the viewpoint of electroneutrality. Voltammograms for the ion transport were generated at steady state and the current density between W1 and W2, jW1–W2, increased with the absolute value of the applied membrane potential, EW1–W2. Then, the magnitude of jW1–W2 at a certain EW1–W2 increased with the hydrophobicity of the counter anion. It was proved that the logarithm of |jW1–W2|at a certain EW1–W2 is almost proportional to the hydration energy of the counter anion. This indicates that not only K+ but also the counter anion distributes into the BLM. Therefore, the magnitude of jW1–W2 at a certain EW1–W2 increased with an increase of pH, because the hydroxide ion was served as a counter anion. Based on the variation of the zero‐current potential in case of various asymmetrical ionic compositions, it is found that the amount of cation transport is much larger than that of anion transport.  相似文献   
109.

Background  

Water immersion therapy is used to treat a variety of cardiovascular, respiratory, and orthopedic conditions. It can also benefit some neurological patients, although little is known about the effects of water immersion on neural activity, including somatosensory processing. To this end, we examined the effect of water immersion on short-latency somatosensory evoked potentials (SEPs) elicited by median nerve stimuli. Short-latency SEP recordings were obtained for ten healthy male volunteers at rest in or out of water at 30°C. Recordings were obtained from nine scalp electrodes according to the 10-20 system. The right median nerve at the wrist was electrically stimulated with the stimulus duration of 0.2 ms at 3 Hz. The intensity of the stimulus was fixed at approximately three times the sensory threshold.  相似文献   
110.
The fibril growth behavior of amyloid β protein (Aβ) on cell membranes is relating to the progression of Alzheimer's disease. This growth behavior of Aβ fibrils is sensitively affected by the metal ions, neurotransmitters, or bioreactive substrate. The inhibitory effect of those materials was quantitatively estimated from the viewpoints of “crystal growth”. In a bulk aqueous solution, copper (II) ion showed the strong inhibitory effect on the growth of Aβ fibrils. Meanwhile, the addition of a closed‐phospholipid bilayer membrane (liposome) could reduce the above inhibitory effect of copper (II) ion. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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