21 Result(s)

Article

Effects of land use on larval Odonata assemblages in cloud forest streams in central Veracruz, Mexico

This study analyzes the effect of stream water quality and its relationship with habitat characteristics on larval Odonata assemblages in streams found in tropical montane cloud forests, pastures, and coffee p...

P. L. García-García, G. Vázquez, R. Novelo-Gutiérrez, M. E. Favila in Hydrobiologia (2017)

Article

Algal assemblages and their relationship with water quality in tropical Mexican streams with different land uses

This study analyzes the relationship between physical and chemical factors and the algal communities in tropical streams in micro-watersheds where >70% of their area has different land uses, specifically, clou...

G. Vázquez, J. A. Aké-Castillo, M. E. Favila in Hydrobiologia (2011)

Article

Modulation of Cytosolic Calcium Levels in Osteoblast-like Osteosarcoma Cells by Olpadronate and its Amino-Derivative IG-9402

The molecular mechanisms as well as the structure/activity relationships involved in the antiresorptive actions of bisphosphonates on bone cells are still not clear. Replacement of the R1-hydroxyl by an NH2 gr...

G. Vazquez, G. Santillan, R. Boland, E. Roldán… in Calcified Tissue International (2003)

Article

Rheology of tannin-added phenol formaldehyde adhesives for plywood

adhesive consumption in double glue line, which is significantly lower than the aprox. 400 g/m² allowed by commercially available phenol-formaldehyde adhesives. The adhesives prepared with resols containing 36% ...

G. Vázquez, J. González-Álvarez, F. López-Suevos… in Holz als Roh- und Werkstoff (2002)

Article

Characterization of Eucalyptus globulus and Pinus pinaster acetosolv pulps prebleached with O2 by FTIR and DRIFT spectroscopy

G. Vázquez, J. González, S. Freire, G. Antorrena in Holz als Roh- und Werkstoff (2002)

Article

Characteristics of Pinus pinaster bark extracts obtained under various extraction conditions

bark extracts obtained by lixiviation with water or alkaline solutions followed by spray drying. Extract yield was 2.5- to 6-fold higher with alkaline extractant solutions than with water. Within the ranges o...

G. Vázquez, J. González-Alvarez, S. Freire, F. López-Suevos… in Holz als Roh- und Werkstoff (2001)

Article

The influence of acetosolv pul** conditions on the enzymatic hydrolysis of Eucalyptus pulps

Eucalyptus globulus wood was subjected first to HCl–catalysed delignification with 70% acetic acid under conditions realizing an incomplete 3 × 3 × 3 factorial design (HCl concentration ...

G. Vázquez, G. Antorrena, J. González, S. Freire, I. Crespo in Wood Science and Technology (2000)

Article

Characterization of Pinus pinaster bark and its alkaline extracts by diffuse reflectance Fourier transform infrared (DRIFT) spectroscopy

bark and of the raffinates obtained after an alkaline extraction, and also the Stiasny number of the corresponding extracts. By means of a stepwise regression analysis a selection of the DRIFT spectra bands w...

G. Vázquez, S. Freire, J. González, G. Antorrena in Holz als Roh- und Werkstoff (2000)

Article

Tannin-based adhesives for bonding high-moisture Eucalyptus veneers: Influence of tannin extraction and press conditions

The alkaline extraction of tannins from Pinus pinaster bark was studied as regards the influence of solid/liquid ratio, extraction time and NaOH concentration on the yield and Stiasny number of the extracts preci...

G. Vázquez, G. Antorrena, J. González, J. C. Alvarez in Holz als Roh- und Werkstoff (1996)

Article

Kinetics of polysaccharide hydrolysis in the acid-catalysed delignification of eucalyptus globulus wood by acetic acid

The influence of operating conditions (temperature, HCl catalyst concentration and time) on the percentage of xylose solubilized in the acid-catalysed delignification of Eucalyptus globulus wood by acetic acid...

G. Vázquez, G. Antorrena, J. González in Wood Science and Technology (1995)

Article

Kinetics of acid-catalysed delignification of Eucalyptus globulus wood by acetic acid

The kinetics of HCl-catalysed delignification of Eucalyptus globulus wood by 70% (w/w) acetic acid solution were satisfactorily explained by a model in which 5% of the lignin fraction could not be eliminated and ...

G. Vázquez, G. Antorrena, J. González in Wood Science and Technology (1995)

Article

Kinetics and mechanism of acetic acid pul** of detannined Pinus pinaster bark

The observed kinetics of Pinus pinaster bark with acetic acid after alkali treatment, with or without intervening acid prehydrolysis, are satisfactorily explained by a model involving both solubilization and c...

G. Vázquez, G. Antorrena, J. González in Wood Science and Technology (1994)

Article

Exterior plywood resins formulated from Pinus pinaster bark extracts

Phenol-tannin-formaldehyde resins prepared by copolymerization of resoles andPinus pinaster bark tannins were used for bonding eucalyptus plywood boards. The dependence of board quality on the formaldehyde/phenol...

G. Vázquez, G. Antorrena, J. L. Francisco, M. C. Arias… in Holz als Roh- und Werkstoff (1993)

Article

Properties of phenolic-tannin adhesives from pinus pinaster bark extracts as related to bond quality in eucalyptus plywoods

Resins were prepared from resoles andPinus pinaster bark tannins by copolymerization at room temperature. Reducing the moisture content of the tannins to below 60% increased their stability, so allowing preparati...

G. Vázquez, G. Antorrena, J. L. Francisco, J. González in Holz als Roh- und Werkstoff (1992)

Article

Preparation of wood adhesives by polycondensation of phenolic acids from pinus pinaster bark with resoles

Resins have been prepared by polycondensing phenolic acids from Pinus pinaster bark (1% NaOH extract) with resoles. Up to 33% of the phenol has been substituted by phenolic acids. With these resins, 5-ply pine...

G. Vázquez, G. Antorrena, J. C. Parajó, J. L. Francisco in Holz als Roh- und Werkstoff (1989)

Article

The D-xylose fermenting capacities of immobilizedPichia stipitis andPachysolen tannophilus

The yeastsP. stipitis NRRL Y-7124 andP. tannophilus NRRL Y-2460 were entrapped in η-carrageenan beads and used for repeated batch fermentation of D-xylose, in a series of four reactors. The operating conditions f...

Ma J. Núñez, A. Sanroman, E. López, G. Vázquez, J. M. Lema in Biotechnology Letters (1989)

Article

Acid prehydrolysis of pinus pinaster bark with dilute sulfuric acid

The influence of temperature (100–150°C) and acid concentration (0–5 wt%) on the prehydrolysis of pine bark and its alkaline-extracted residues was studied (the latter were obtained by vigorously stirring the ...

G. Vázquez, G. Antorrena, J. C. Parajó, X. L. Francisco in Wood Science and Technology (1988)

Article

Sugars from pine bark by enzymatic hydrolysis effect of sodium chlorite treatments

For the utilization of polysaccharides from Pinus pinaster bark, both untreated and NaOH-treated samples were delignified to different stages using NaClO₂ and submitted to enzymatic hydrolysis with Trichoderma re...

G. Vázquez, J. C. Parajó, G. Antorrena, Ph. Thonart… in Wood Science and Technology (1987)

Article

Studies on the utilization of Pinus pinaster bark

The influence of several variables (temperature, time, alkali type and concentration) on the yield of polyphenol from alkaline extractions is studied, using Pinus pinaster bark. For this purpose, the gravimetric ...

G. Vázquez, G. Antorrena, J. C. Parajó in Wood Science and Technology (1987)

Article

Studies on the utilization of Pinus pinaster bark

The chemical constituents of Pinus pinaster bark are studied, as a first step of a study devoted to its benefit. The analyzed samples showed an average content of 0.5% ash, 2.5% waxes (measured as the hexane and ...

G. Vázquez, G. Antorrena, J. C. Parajó in Wood Science and Technology (1987)