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61.
Tomaž Klinc 《Communications in Mathematical Physics》1975,41(3):273-279
It is shown that the set of Case's eigenfunctions of the one speed transport equation is complete in the rigged Hilbert spaceW 2 1 ([?1, 1])?L 2(?1, 1)?W 2 ?1 ([?1, 1]). 相似文献
62.
In the presence of 0.5-1 mol % of FeCl(3) with lithium bromide as a crucial additive, alkynyl Grignard reagents, prepared from the corresponding alkynes and methylmagnesium bromide, react with alkenyl bromides or triflates to give the corresponding conjugated enynes in high to excellent yields. The reaction shows wide applicability to various terminal alkynes and alkenyl electrophiles. 相似文献
63.
Shinobu Koda Masaki Miyamoto Maricela Toma Tatsuro Matsuoka Masahiro Maebayashi 《Ultrasonics sonochemistry》2009,16(5):655-659
This paper shows a systematic study of the 500 kHz frequency ultrasound efficiency on the microbial inactivation as a function of ultrasonic power delivered into the bacterial suspension. The inactivation of Escherichia coli IAM 12058, a Gram-negative bacterium and Streptococcus mutans JCM 5175, a Gram-positive bacterium is enhanced by increasing the ultrasonic power in the range of 1.7–12.4 W and the logarithm of survival ratio decreases linearly with irradiation time, except for E. coli sonicated with the highest power level. The rate constants were estimated in the linear region of the plots representing survival ratio logarithm vs. sonication time. A better understanding of the inactivation process at 500 kHz could be gained by suppressing the chemical effects with a radical scavenger. We find out that the rate constants increase with the ultrasonic power delivered into the solution and dramatically decrease by the addition of t-butanol as a radical scavenger to the bacterial suspension. For comparison, experiments were carried out at a low frequency level of 20 kHz. It was found out that for the same ultrasonic power delivered into the bacterial suspension, the inactivation was slightly enhanced at 500 kHz frequency. The examinations of bacterium performed with a TEM revealed lethal damages arising from the interaction of bacterial cells with the cavitational bubbles. A significant amount of empty cell envelopes as well as their cytoplasmatic content was detected. Thus, based on these new data, the mechanism of bacterial inactivation by ultrasounds at high frequency is discussed here. 相似文献
64.
Károly Lázár Andjelka Toma?evi? Goran Bo?kovi? Ern? Kiss 《Hyperfine Interactions》2009,192(1-3):23-29
Catalytic performances of Fe-AlPILC (14 wt.% Fe) and Fe-ZSM-5 (5 wt.% Fe) catalysts are compared in the wet oxidative degradation of methomyl. Fe-ZSM-5 exhibits outstanding whereas Fe-AlPILC shows only mediocre activity. Positions of iron are analysed in the two catalysts by Mössbauer spectroscopy. Iron is in highly dispersed state in Fe-AlPILC whereas in the other case a hematite/ZSM-5 composite is formed. The catalytic activity is attributed to iron located and stabilized in ionic dispersion. 相似文献
65.
C. Cristache K. Gméling O. Culicov M. V. Frontasyeva M. Toma O. G. Duliu 《Journal of Radioanalytical and Nuclear Chemistry》2009,279(1):7-12
A comparative study performed by means of both epithermal neutron activation analysis (ENAA) and prompt gamma neutron activation
analysis (PGAA) concerning the distribution of 9 elements (Na, Al, Cl, K, Ca, Ti, Mn Fe and Sm) in unconsolidated sediments
collected from the Black Sea anoxic region is presented. Principal component analysis (PCA) was used as a supplementary method
in interpreting experimental data. The final results have shown that eight of them (Na, Al, Cl, K, Ti, Mn, Fe and Sm) have
concentrations which differ by less than 30% from the corresponding concentrations of Upper Continental Crust (UCC), confirming
the continental origin of sediments. At the same time, Ca concentration was about six times higher than that of UCC, this
significant enrichment being due to the presence of the neighbouring oxygenated zone of considerable deposits of shell debris,
characteristic of the Western Black Sea Continental Platform. Excepting Na and Mn, the concentrations of all other elements
involved in this intercomparison were coincident within one standard deviation which attests the accuracy of this test. At
the same time, PCA revealed the presence of five clusters, which could be put into concordance with the mineralogical composition
of sediments, each of them consisting in equal proportions of elements determined by both methods. 相似文献
66.
Abstract
Several achiral and chiral basic ionic liquids (ILs) were prepared and tested as the medium for Ru-catalyzed hydrogen-transfer reduction of different aromatic ketones. Hydrogen-transfer reduction of ketones proceeded well in achiral basic ILs using chiral catalysts. The interesting observation was made that raising the reaction temperature did not have a negative effect on enantioselectivity of the reaction. On the other hand no reaction was observed in chiral ILs. 相似文献67.
Dr. Régis Y. N. Gengler Prof. Dr. Dimitrios Gournis Akfiny H. Aimon Dr. Luminita M. Toma Prof. Dr. Petra Rudolf 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(24):7594-7600
Much of the research effort concerning the nanoscopic properties of clays has focused on its mechanical applications, for example, as nanofillers for polymer reinforcement. To broaden the horizon of what is possible by exploiting the richness of clays in nanoscience, herein we report a bottom‐up approach for the production of hybrid materials in which clays act as the structure‐directing interface and reaction media. This new method, which combines self‐assembly with the Langmuir–Schaefer technique, uses the clay nanosheets as a template for the grafting of C60 into a bi‐dimensional array, and allows for perfect layer‐by‐layer growth with control at the molecular level. In contrast to the more‐common growth of C60 arrays through nanopatterning, our approach can be performed under atmospheric conditions, can be upscaled to areas of tenths of cm2, and can be applied to almost any hydrophobic substrate. Herein, we report a detailed study of this approach by using temperature‐dependent X‐ray diffraction, spectroscopic measurements, and STM. 相似文献
68.
A rapid conversion of aldehydes to corresponding nitriles has been achieved under microwave irradiation using hydroxylamine and phthalic anhydride or hydroxylamine and Envirocatalyst EPZGR in solvent free conditions. 相似文献
69.
70.
The linear equivalence method (LEM), introduced by [Bull. Math. Soc. Sci. Math. de la Roumanie 24 (72) (1980) 4417; An. Univ. Bucure
ti, ser. Matematica 31 (1982) 75] to get solutions of nonlinear ODEs, was used so far to get differential type representations. New LEM representations of integral type are presented here and used for the study of the nonlinear elastic bar; a good approximating formula for the rotation of the cross-section at the bar end is also obtained, in case of a simply supported bar. A parallel old–new results is made by means of a programming code. 相似文献