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1.
Teresa uczak Radosaw Pankiewicz Bogusawa ska Grzegorz Schroeder Maria Betowska-Brzezinska Bogumil Brzezinski 《Journal of Molecular Structure》2006,800(1-3):140-145
Novel self-assembled monolayers were obtained on silver using 4,7-diazaheptyl-trimethoxy-silane (SiN) and vinyl-trialkoxy-silane (SiVA, where the alkyl group is 3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-eicozaoxa- hexaheptaconan). It was shown that thus modified metal surface was protected against electrooxidation. A densely packed monolayer remained stable and did not desorb from the Ag electrode on the potential cycling. The structure of SiN and SiVA as well as their complexes with Li+ cations were calculated and visualised by the AM1d and PM5 semi-empirical methods. 相似文献
2.
3.
C. Sun M.D. Thouless A.M. Waas J.A. Schroeder P.D. Zavattieri 《International Journal of Solids and Structures》2008,45(17):4725-4738
To enable the effective and reliable use of structural adhesive bonding in automotive applications, the cohesive properties of a joint need to be determined over a wide range of loading rates. In this paper, a strategy for determining these properties has been described and used to analyze a set of experimental results presented in a companion paper. In the particular system studied, a crack growing in a toughened quasi-static mode could make a catastrophic transition to a brittle mode of fracture. The cohesive parameters for both the toughened and brittle modes of crack growth were determined by comparing numerical predictions from cohesive-zone simulations to the results of experimental tests performed using double-cantilever beam specimens and tensile tests. The cohesive parameters were found to be essentially rate-independent for the toughened mode, but the toughness dropped by a factor of four upon a transition to the brittle mode. The results of wedge tests were used as an independent verification of the cohesive parameters, and to verify that the quasi-static properties remained rate-independent to very high crack velocities corresponding to conditions of low-velocity impact. The effects of friction, and the use of the wedge test to determine cohesive parameters, were also explored. 相似文献
4.
5.
Gang XU Cheng Cai AN Jun FENG Yun Xiang CI Jin Hua TIAN Zhang Liang CHENI 《中国化学快报》2000,11(7):597-600
IthasbeenreportedthatTrichosanthi11(TCS),isolatedfromrkiI-ilolt)ii,hasanti-tumorI-4andanti-vira1activities5-'.Someanti-tun1orremedies,whicharedesignedfromTCS,arebeingtestedanddeveloped'-.'.StudyingthebioIogicalphenomenonbyelectrochemicalmethodsisanewhotresearchspotemerginginrecentyears".Manyresultsshowedthatnotonlytheenzymesystemsuchassuccinatedehydrogenasedisplayedthediode-likebehaviorduringtheelectrontransferprocess",butalsothehigh1yorganizedorganeIle,forexample,mitochondria,andevenintac… 相似文献
6.
Rybachenko V. I. Schroeder G. Chotii K. Yu. Lenska B. Kovalenko V. V. Red'ko A. N. 《Theoretical and Experimental Chemistry》2003,39(6):359-363
We have studied the rate of 15 reactions of acyl transfer from O-acyl salts of 4-dimethylaminostyryl-4-pyridine N-oxide to 4-morpholinopyridine and 4-dimethylaminopyridine N-oxides in acetonitrile solutions. Analysis of the results based on the Shaik – Pross approach and the Marcus equation shows that if the structure of the acyl group is varied, then the reactivity is determined by such parameters as the resonance interaction in the transition state (B) or the internal barrier (G
0) of the reaction. 相似文献
7.
The Cr(CO)3(CH3CN)3 complex is found to catalyze the 1,4-addition of hydrogen to 1,3-dienes such as 2-methyl-1,3-butadiene, trans-1,3-pentadiene, and trans, trans-2,4-hexadiene at low temperature (40°) and low H2 pressure (20 psi). For trans, trans-2,4-hexadiene the only product obtained when D2 is used is 2,5-dideuterio-cis-3-hexene. The catalytic 1,4-hydrogenation can be carried out in neat dienes, and turnover numbers for the catalyst of greater than 3000 have been observed. 相似文献
8.
Grohmann K. Mitchell D. J. Himmel M. E. Dale B. E. Schroeder H. A. 《Applied biochemistry and biotechnology》1989,(1):45-61
Xylan backbones in native plant cell walls are extensively acety-lated. Previously, no direct investigations as to their role
in cellulolytic enzyme resistance have been done, though indirect results point to their importance. An in vitro deesterification
of aspen wood and wheat straw has been completed using hydroxylamine solutions. Yields of 90% acetyl ester removal for both
materials have been accomplished, with little disruption of other fractions (i.e., lignin). Apparently, as the xylan becomes
increasingly deacetylated, it becomes 5–7 times more digestible. This renders the cellulose fraction more accessible, and
2–3 times more digestible. This effect levels off near an acetyl removal of 75%, where other resistances become limiting. 相似文献
9.
10.
Edgardo Laborde John S. Kiely Lawrence E. Lesheski Mel C. Schroeder 《Journal of heterocyclic chemistry》1991,28(1):191-198
A convergent synthesis of 1,8-naphthyridine antibacterials bearing a carbon-carbon bonded, acyclic or cyclic vinyl substituent at the C-7 position has been achieved. The synthetic methodology is based upon the palladium-catalyzed cross coupling of a 7-chloro-1,8-naphthyridine with an appropriately substituted organotin reagent. 相似文献