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101.
102.
Aline de Souza Ramos Joyce Benzaquem Ribeiro Leonardo Vazquez Selma Gomes Ferreira Leite Francisco Radler de Aquino Neto 《Tetrahedron letters》2009,50(52):7362-6129
The enantioselective reduction of ethyl benzoylacetate (EBA) into ethyl (S)-3-hydroxy-3-phenylpropanoate (S-HPPE) by nine yeast strains and three filamentous fungi strains is described. The conversion obtained was in the range 0-89% and the enantiomeric excess was 100% in many cases. Conversion levels were higher when the reduction was performed with microorganisms immobilized in calcium alginate and enantioselectivity remained excellent. Some reaction’s conditions of bioreduction by immobilized cells of Rhodotorula rubra were studied using a 25-2 fractional factorial design. 相似文献
103.
104.
We show that for a vast class of matrix Lie groups, which includes the orthogonal and the symplectic, diagonal Padé approximants of log((1+x)/(1−x)) are structure preserving. The conditioning of these approximants is analyzed. We also present a new algorithm for the Briggs–Padé method, based on a strategy for reducing the number of square roots in the inverse scaling and squaring procedure. 相似文献
105.
Leite Irena Andrianov Victor Zelencova-Gopejenko Diana Loza Einars Kazhoka-Lapsa Iveta Domracheva Ilona Stoyak Marta Chlopicki Stefan Kalvins Ivars 《Chemistry of Heterocyclic Compounds》2021,57(11):1086-1106
Chemistry of Heterocyclic Compounds - Acyl derivatives of aziridine-2-carboxylic acid have been synthesized and tested as PDIA1 inhibitors. Calculations of charge value and distribution in... 相似文献
106.
107.
108.
Amal Al-Kahlout Diogo Vieira César O. Avellaneda Edson R. Leite Michel A. Aegerter Agnieszka Pawlicka 《Ionics》2010,16(1):13-19
Proton-conducting gel polymer electrolytes based on gelatin plasticized with glycerol and containing acetic acid were investigated,
characterized, and applied to electrochromic window. For glycerol contents varying from 7% to 48%, the conductivity of the
uniform and predominantly amorphous gel electrolyte was found to follow a Vogel–Tamman–Fulcher behavior with the temperature.
Typically, for the electrolyte chosen to make 7 × 2 cm2 electrochromic smart window with the configuration: glass/fluor-doped tin oxide (FTO)/WO3/gelatin electrolyte/CeO2–TiO2/FTO/glass and containing 28% of glycerol, the conductivities were found to be of the order of 5 × 10−5 S/cm at room temperature and 3.6 × 10−4 S/cm at 80 °C. The device was characterized by spectroelectrochemical techniques and was tested up to 10,000 cycles showing
a fast coloring/bleaching behavior, where the coloring process was achieved in 10 s and the bleaching in 2 s. The transmission
variation at the wavelength of 550 nm was about 15%. The cyclic voltammograms showed a very good reversibility of the cathodic/anodic
processes, and the charge density was about 3.5 mC/cm2. The memory tests showed that the transmittance in the colored state increased by 8% in 90 min after removing the potential. 相似文献
109.
S. Belyakov M. Fleisher D. Jansone L. Leite E. Lukevics 《Chemistry of Heterocyclic Compounds》2009,45(4):417-421
Monocrystals of the trans and cis isomers of 3-cyano-4-[2-(4-methoxyphenyl)vinyl]-6,6-dimethyl-5,6-dihydro-2H-pyran have been obtained and an X-ray structural
analysis of them has been carried out. Both compounds have a molecular structure corresponding to symmetry group C1. The heterocyclic ring is in a distorted envelope conformation. The crystals of the trans isomer are rhombic and have a fir-tree type of packing. The crystal packing of the cis isomer is formed by pairs of molecules, each of which consists of only one enantiomer.
*Dedicated to deeply respected Professor Hank van der Plas in connection with his jubilee.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 535-540, April, 2009. 相似文献
110.
A lattice model is used to study mutations and compacting effects on protein folding rates and folding temperature. In the context of protein evolution, we address the question regarding the best scenario for a polypeptide chain to fold: either a fast nonspecific collapse followed by a slow rearrangement to form the native structure or a specific collapse from the unfolded state with the simultaneous formation of the native state. This question is investigated for optimized sequences, whose native state has no frustrated contacts between monomers, and also for mutated sequences, whose native state has some degree of frustration. It is found that the best scenario for folding may depend on the amount of frustration of the native structure. The implication of this result on protein evolution is discussed. 相似文献