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101.
102.
Marina K. Kadowaki Cristina G. M. Souza Rita C. G. Simão Rosane M. Peralta 《Applied biochemistry and biotechnology》1997,66(2):97-106
Aspergillus tamarii has been found to grow well and to produce high cellulase-free xylanase activity when growing on corn cob powder as the principal
substrate. Maximum xylanase production (285-350 U/mL) was obtained when the strain was grown in media supplemented with high
corn cob concentration (5-8%, w/v) for 5 d. The presence of constitutive levels of xylanase was detected in cultures with
glucose as the carbon source. Zymogram analysis for detection of xylanase activity after electrophoresis in polyacrylamide
gels has shown thatA. tamarii produces at least two xylanases under the conditions utilized. The hydrolysis patterns of xylan demonstrated that the xylanases
were endoenzymes, yielding mainly xylobiose, xylotriose, and higher xylooligosaccharides with traces of xylose. 相似文献
103.
Marcus Vinícius Nora de Souza Maria Cristina Silva Lourenço Mônica Amado Peralta Raoni Schroeder Borges Gonçalves Thais Cristina Mendonça Nogueira Camilo Henrique da Silva Lima 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2990-2997
The series of new N,N′-di(thiopheneacetyl)diamines derivatives, 8–17, were synthesized and evaluated for their in vitro antibacterial activity against Mycobacterium tuberculosis(TB), and the activity expressed as the minimum inhibitory concentration (MIC) in μ g/mL. Compound 13 was the only one determined to be active and exhibited a MIC 50 μg/mL, indicating that the alkyl chain-length of the diamines is critical for biological activity. This class of compound has not been evaluated before, and it could be a good starting point to find new lead compounds in the fight against multi-drug resistant TB. 相似文献
104.
Laetitia Bomble Stephan N. Steinmann Nancy Perez‐Peralta Gabriel Merino Clemence Corminboeuf 《Journal of computational chemistry》2013,34(26):2242-2248
The multicenter bonding pattern of the intriguing hexa‐, hepta‐, and octacoordinate boron wheel series (e.g., , , , and SiB8 as well as the experimentally detected isomer) is revised using the block‐localized wave function analyzed by the localized orbital locator (BLW‐LOL). The more general implementation of BLW combined with the LOL scalar field is not restricted to the analysis of the out‐of‐plane π‐system but can also provide an intuitive picture of the σ‐radial delocalization and of the role of the central atom. The results confirm the presence of a π‐ring current pattern similar to that of benzene. In addition, the LOLπ isosurfaces along with the maximum intensity in the ΔLOL profiles located above and below the ring suggest that the central atom plays a minor role in the π‐delocalized bonding pattern. Finally, the analysis of the σ‐framework in these boron wheels is in line with a moderated inner cyclic rather than disk‐type delocalization. © 2013 Wiley Periodicals, Inc. 相似文献
105.
106.
Víctor M. Ovando-Medina René D. Peralta Eduardo Mendizábal 《Colloid and polymer science》2009,287(5):561-568
Vinyl acetate and butyl acrylate were copolymerized in microemulsion under monomer-starved conditions by a semicontinuous process using different monomer addition rates (R a). A mixture of sodium dodecyl sulfate and polyethylene glycol dodecyl ether (Brij®35) were used as surfactants. Potassium persulfate was the initiator. High copolymer content latexes (around 40 wt.%), average particle diameters (D p)?50 nm and polymer-to-surfactant ratios (12 to 14, weight/weight) were obtained with weight average molar masses (M w) between 180,000 and 760,000. D p and M w of the copolymers decrease as R a is decreased. As R a increases, a shoulder in the molar mass distribution was observed at high values of M w, which was ascribed to chain transfer to polymer. Homogeneous copolymer compositions were observed throughout the reaction, which cannot be obtained by the usual batch process. 相似文献
107.
Antonio M. Peralta 《Mathematische Nachrichten》2003,256(1):100-106
In the last twenty years, a theory of real Jordan triples has been developed. In 1994 T. Dang and B. Russo introduced the concept of J*B–triple. These J*B–triples include real C*–algebras and complex JB*–triples. However, concerning J*B–triples, an important problem was left open. Indeed, the question was whether the complexification of a J*B–triple is a complex JB*–triple in some norm extending the original norm. T. Dang and B. Russo solved this problem for commutative J*B–triples. In this paper we characterize those J*B–triples with a unitary element whose complexifications are complex JB*–triples in some norm extending the original one. We actually find a necessary and sufficient new axiom to characterize those J*B–triples with a unitary element which are J*B–algebras in the sense of [1] or real JB*–triples in the sense of [4]. 相似文献
108.
Diego Moreno Gerardo Martínez‐Guajardo Dr. Andrés Díaz‐Celaya Dr. José M. Mercero Prof. Romeo de Coss Dr. Nancy Perez‐Peralta Prof. Gabriel Merino 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(38):12668-12672
The potential energy surface of C6Li6 was re‐examined and a new non‐symmetric global minimum was found. The new structure can be described as three C22? fragments strongly aggregated through lithium bridges. At high temperatures, fluxionality is perceived instead of dissociation. At 600 and 900 K, the BOMD simulations show that the lithium mobility is high, indicating that the cluster behaves in a liquid‐like manner (BOMD=Born–Oppenheimer molecular dynamics). 相似文献
109.
110.
Carrascal M Schneider K Peralta C Escolar G Gelpi E Abian J 《Biomedical chromatography : BMC》2004,18(6):388-395
A method for the quantitative analysis of endothelin peptides in human umbilical vein endothelial cell (HUVEC) culture supernatants is reported. The analysis is isoform-specific and employs solid-phase extraction and subsequent HPLC fractionation followed by HPLC-ESIMS analysis. The peptide vasoactive-intestinal-contractor (VIC) was used as internal standard for the HPLC-ESIMS analysis. Linearity of calibration curves was from 50 fmol to 25 pmol. The limit of detection of the HPLC-ESIMS step using a buffer matrix was estimated at 50 fmol (S/N > 3). The overall limit of detection for supernatants of HUVEC was 500 fmol/mL. In HUVEC culture supernatants only ions of endothelin-1 (ET1) were observed. Basal levels were determined to be 1.8 +/- 0.3 pmol/mL. Quantitative results obtained for ET1 were in agreement with those obtained by using a standard addition method and by an ELISA method. 相似文献