Polymer concrete (PC) is a composite material prepared by resin and aggregates. Advantages of polymer concretes include rapid curing at ambient temperatures, high flexural and compressive strengths, excellent chemical resistance and low permeability. In this research, a comparative study was performed on degradation of polyester resin concrete in different chemical solutions. Polymer concrete s...

In numerous Gram-positive bacteria, the glmS ribozyme or catalytic riboswitch regulates the expression of glucosamine-6-phosphate (GlcN6P) synthase via site-specific cleavage of its sugar-phosphate backbone in response to GlcN6P ligand binding. Biochemical data have suggested a crucial catalytic role for an active site guanine (G40 in Thermoanaerobacter tengcongensis, G33 in Bacillus anthracis)...

BACKGROUND In recent years, the perceived threat of chemical terrorism has increased. It is hoped that teaching civilians how to behave during a chemical incident will decrease the number of "worried well" patients at hospitals, reduce secondary contamination, and increase compliance with the instructions of emergency services. The governments of the United Kingdom and Israel sent booklets to e...

Volatile organic compounds (VOCs) are chemical whose saturation vapor pressures greater than 102 kPa at 25 °C. Both plants and microorganisms produce VOCs that allow them to communicate intra- inter-specifically. By emitting VOCs, defend themselves against herbivores pathogens, warn their neighbors of the attack, compete with other plants, and/or feed microbial populations. Microorganisms emit ...