quebracho tannin wood adhesive in non formaldehyde approach has low autocondensation rate and needs more press time than formaldehyde-based wood adhesives to produce wood composites. in this study, boric acid was used to increase autocondensation rate of quebracho tannin adhesive to make poplar plywood. the main ingredients of the adhesives include quebracho tannin, naoh, hexamine, boric acid a...

Microporous carbon catalysts with large surface areas (800-1100 m(2) g(-1)) and high densities of SO3H groups (ca. 1.1 mmol g(-1)) were synthesized by sulfonation of zeolite-templated microporous carbon. The resulting SO3H-bearing microporous carbon catalysts exhibited higher catalytic performance for the hydrolysis of cellobiose and the Beckmann rearrangement than conventional solid acid catal...

−− The adsorption process of Nickel and Vanadium dissolved in acid liquor on lignin is studied in this work. Different adsorption isotherm models are used to adjust liquid-solid systems: Langmuir, Freundlich and Redlich-Peterson. It was obtained that the metal adsorption using lignin proceeds by similar chemical mechanisms. Possibly the Nickel is adsorbed in heterogeneous monolayers, contrary t...

Many industrial applications of protonic zeolites as solid-acid heterogeneous catalysts rely on the strength or their Br nsted acidity, which (together with zeolite topology) affects both, catalytic activity and selectivity. Therefore, convenience to have an accurate (and simple) experimental technique for measuring acid strength. The enthalpy change, Delta H 0 , corresponding hydrogen bonding ...

The epoxidation reaction using heterogeneous solid catalysts with H2O2 as oxidants are environmentally friendly routes to produce extensively useful epoxides which are traditionally obtained from capital-intensive or environmentally polluted processes. In this paper, various types of solid catalysts for the epoxidation of olefins with H2O2 as oxidants are reviewed. The efficient catalysts repor...

The disposal of solid waste is a serious problem worldwide that is made worse in developing countries due to inadequate planning and unsustainable solid waste management. In Mexico, only 2% of total urban solid waste is recycled. One non-recyclable material is poly (styrene-co-butadiene), which is commonly used in consumer products (like components of appliances and toys), in the automotive ind...

Chiral cylindrical molecular complexes of homo- and hetero-double-helices derived from helicene oligomers self-assemble in solution, providing functional heterogeneous liquid-solid materials. Gels and liotropic liquid crystals are formed by fibril self-assembly in solution; molecular monolayers and fibril films are formed by self-assembly on solid surfaces; gels containing gold nanoparticles em...

The applications of molecular surface chemistry in heterogeneous catalyst technology, semiconductor-based technology, medical technology, anticorrosion and lubricant technology, and nanotechnology are highlighted in this perspective. The evolution of surface chemistry at the molecular level is reviewed, and the key roles of surface instrumentation developments for in situ studies of the gas-sol...

We report a case of ganglioneurocytoma manifesting as a complex partial seizure in a young adult male. MR images depicted a well-marginated cystic mass with a heterogeneous solid portion abutting the dura in the parietal lobe. The solid portion showed minimal heterogeneous enhancement, and pressure erosion of the overlying calvarium had occurred. Following gross total resection, the clinical ou...