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41.
42.
beta-Nitroenamines having a formyl group at the beta-position behave as the synthetic equivalent of unstable nitromalonaldehyde, which is a useful synthon for syntheses of versatile nitro compounds. High solubility of the nitroenamines into general organic solvents enables us to conduct reactions in the organic media accompanied by easy experimental manipulations and considerable safety. When nitroenamines are treated with 1,2-bifunctional nucleophiles such as hydrazines, hydroxylamine and glycine ester, nitrated pyrazoles, isoxazole and pyrrole-2-carboxylate were readily prepared. This methodology was also applicable to guanidines and 1,2-diamines, leading to pyrimidines and 1,4-diazepines, respectively.  相似文献   
43.
44.
The radical-scavenging activities of the synthetic antioxidants 2-allyl-4-X-phenol (X = NO2, Cl, Br, OCH3, COCH3, CH3, t-(CH3)3, C6H5) and 2,4-dimethoxyphenol, and the natural antioxidants eugenol and isoeugenol, were investigated using differential scanning calorimetry (DSC) by measuring their anti-1,1-diphenyl-2-picrylhydrazyl (DPPH) radical activity and the induction period for polymerization of methyl methacrylate (MMA) initiated by thermal decomposition of 2,2'-azobisisobutyronitrile (AIBN) and benzoyl peroxide (BPO). 2-Allyl-4-methoxyphenol and 2,4-dimethoxy-phenol scavenged not only oxygen-centered radicals (PhCOO*) derived from BPO, but also carbon-centered radicals (R*) derived from the AIBN and DPPH radical much more efficiently, in comparison with eugenol and isoeugenol. 2-Allyl-4-methoxyphenol may be useful for its lower prooxidative activity.  相似文献   
45.
We highlight versatile applicability of a structure-factor indirect Fourier transformation (IFT) technique, hereafter called SQ-IFT. The original IFT aims at the pair distance distribution function, p(r), of colloidal particles from small angle scattering of X-rays (SAXS) and neutrons (SANS), allowing the conversion of the experimental form factor, P(q), into a more intuitive real-space spatial autocorrelation function. Instead, SQ-IFT is an interaction potential model-free approach to the 'effective' or 'experimental' structure factor to yield the pair correlation functions (PCFs), g(r), of colloidal dispersions like globular protein solutions for small-angle scattering data as well as the radial distribution functions (RDFs) of molecular liquids in liquid diffraction (LD) experiments. We show that SQ-IFT yields accurate RDFs of liquid H(2)O and monohydric alcohol reflecting their local intermolecular structures, in which q-weighted structure function, qH(q), conventionally utilized in many LD studies out of necessity of performing direct Fourier transformation, is no longer required. We also show that SQ-IFT applied to theoretically calculated structure factors for uncharged and charged colloidal dispersions almost perfectly reproduces g(r) obtained as a solution of the Ornstein-Zernike (OZ) equation. We further demonstrate the relevance of SQ-IFT in its practical applications, using SANS effective structure factors of lysozyme solutions reported in recent literatures which revealed the equilibrium cluster formation due to coexisting long range electrostatic repulsion and short range attraction between the proteins. Finally, we present SAXS experiments on human serum albumin (HSA) at different ionic strength and protein concentration, in which we discuss the real space picture of spatial distributions of the proteins via the interaction potential model-free route.  相似文献   
46.
Chiral amnesia : Experimental results demonstrate that the double solubility rule indeed holds true for the solution‐phase enantiomers of a conglomerate‐forming solid under fast‐racemizing conditions. There is neither experimental evidence for chiral recognition via solution‐phase clusters nor a need to invoke them to produce a lucid explanation of the compelling model for the evolution of solid‐phase homochirality first communicated by Viedma.

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47.
Lindera umbellata (Lu) essential oil primarily contains linalool and has relaxation properties. We investigated the psychological and antibacterial effects of footbath with Lu essential oil. The participants included 20 women without medical history and received two intervention plans: footbath without any essential oil and footbath using Lu essential oil. Next, questionnaires regarding impressions and mood states were provided for them to answer. In addition, their autonomic nervous system activity was measured, and the aerobic viable of count on the feet was determined. The high-frequency value reflecting the parasympathetic nervous system activity significantly increased after footbath using Lu essential oil. In the questionnaire about the mood states, the subscale scores of tension–anxiety, depression, fatigue, and confusion after intervention were lower than those before intervention regardless of the use of the essential oil. Conversely, the anger–hostility score decreased only in the group using Lu essential oil. Furthermore, the decrease in aerobic viable count after intervention was not significantly different between the two groups. Footbath using Lu essential oil increased the parasympathetic nervous system activity and relieved anger. Taken together, we suggest that footbath using Lu essential oil has a relaxation effect.  相似文献   
48.
Fifteen GSJ (Geological Survey of Japan) and six KIER (Korean Institute of Energy and Resources; now Korean Institute of Geology, Mining and Materials, KIGAM) igneous rock series and nine GSJ sedimentary rock series reference samples were analysed for 21–29 elements by neutron and/or photon activation analysis (NAA and PAA); 14 MeV-NAA for Si and Al, fission track method for U, radiochemical and instrumental NAA for rare earth elements, with reactor neutrons for the latter two. Instrumental neutron and photon AA for the remaining elements were performed with reactor neutrons and bremsstrahlung of end-point energy of 30 MeV, respectively. The reactor irradiations were performed at core sites and also a thermal column of the Kyoto University Research Reactor. All of the radioassays were performed by -ray spectrometry with HPGe-detectors. The present results from the different types of irradiation are compared and discussed in terms of elemental abundances and rock types.  相似文献   
49.
1H-1-Benzazepines were synthesized by thermal ring opening of 2a,7b-dihydrocyclobut[b]indoles. The thermal and photochemical behavior of the 1H-1-benzazepines is also described.  相似文献   
50.
The standardised procedure for dehydrogenation of indolines into indoles with phenylseleninic anhydride 1 was successfully applied to the final steps in the total synthesis of ergot alkaloids.  相似文献   
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