In this paper, the stabilization of a lipase from Bacillus thermocatenulatus (BTL2) by a new strategy is described. First, the lipase is selectively adsorbed on hydrophobic supports. Second, the carboxylic residues of the enzyme are modified with ethylenediamine, generating a new enzyme having 4-fold more amino groups than the native enzyme. The chemical amination did not present a significant ...

In this study, lignin, an aromatic compound from the forestry industry, was used as a renewable material to synthesize a new aromatic amine curing agent for epoxy resin. Firstly, lignin was separated from black liquor and hydroxyl groups were converted to tosyl groups as leaving groups. Then, primary amination was conducted using an ammonia solution at high pressure and temperature, in the pres...

Graphene oxides (GOs) with different surface characteristics, such as size, reduction degree and charge, are prepared, and their effects on the specificity of polymerase chain reaction (PCR) are investigated. In this study, we demonstrate that GO with a large size and high reduction degree is superior to small and nonreduced GO in enhancing the specificity of PCR. Negatively charged polyacrylic...

Silicon anodes require polymer binder systems that are both mechanically robust and electrochemically stable, to accommodate the dramatic volume expansion experienced during cycling operation. Herein, we report use of a poly(acrylic acid)-grafted styrene–butadiene rubber (PAA-g-SBR) with 80% partially neutralized Na-PAA as system for silicon-graphite anodes. The PAA-g-SBR graft copolymer was sy...

results the dna-dna hybridization experiments between isolate tbz3, h. denitrificans and h. saccharevitans revealed relatedness levels of 57% and 65%, respectively. according to gc-ms results, tbz3 degrades paa to benzene, hexyl butanoate, 3-methyl-1-heptanol and hexyl hexanoate. temperature 32.92°c, ph 6.76, and salinity 14% are the optimum conditions for biodegradation with a confidence level...

Cellular patterning on biomaterial surfaces is important in fundamental studies of cell-cell and cell-substrate interactions, and in biomedical applications such as tissue engineering, cell-based biosensors, and diagnostic devices. In this study, we combined the layer-by-layer polyelectrolyte multilayer deposition and photolithographic technique to create an easy and versatile technique for cel...

Owing to its superior mechanical properties, nanodiamond (ND) holds great potential to improve tribological characteristics of composites. In this study, we report on the wear and dry friction of epoxy-ND composites prepared from as-received and aminated ND across the length scale range from macro to nano. Comparison of macroscale, microscale, and nanoscale frictional behavior shows that ND is ...