H ighly trained search-and-rescue (SAR) dogs are indispensable members of urban SAR teams responding to a variety of natural and man-made disasters. A large-scale disaster could result in the release and mixing of dozens or even hundreds of chemical agents. Therefore, urban disaster sites should be considered potentially contaminated with many dangerous chemicals and substances. In a previous r...

A Monte Carlo simulation study of water and hydrocarbons aiming at understanding the degradation of polyethylene cable insulation is presented. Atomistic simulations of water, hydrocarbons and ions are presented. The SPC/E and TraPPE potential functions are used. The equilibrium distributions and clustering of water in vapour and in hydrocarbons was investigated using Gibbs-ensemble Monte-Carlo...

The concept of disjoint NBMOs in diradical alternant hydrocarbons (AHs) is reviewed and extended to diradical nonalternant hydrocarbons (nonAHs). A valence-bond (VB) method for recognizing disjoint versus nondisjoint NBMOs (nonbonding molecular orbitals) in diradicals is presented. When circumscribed with hexagonal rings, disjoint diradicals produce nonradical polycyclic successors and nondisjo...

D ufour G land, Harpagoxenus, Heptadecane, (£)-ß-Farnesene, Homofarnesene The volatile components of tlic Dufour gland sccrcticn of wcrlvcrs cf t*!C eint arpoxeni+s sublaevis have been analysed by gas chromatography and mass spectrometry. Over 20 compo­ nents have been identified, consisting of linear and terpenoid hydrocarbons. Each gland contains approximately 6 ng of hydrocarbons with n-hept...

today oil removal from contaminated soil by new methods such as bioremediation is necessary.  in this paper, the effect of chemical fertilizers and aeration on bioremediation of oil-contaminated soil has been investigated. also the control group, (bioremediation of petroleum hydrocarbons in contaminated soil without treatment by chemical fertilizers and aeration treatment was examined. the cond...

Crude oil is a complex mixture of hydrocarbons with different structures; its components vary in bioavailability and toxicity. It is important to understand how bacterial communities response to different hydrocarbons and their co-acclimation in the process of degradation. In this study, microcosms with the addition of structurally different hydrocarbons were setup to investigate the succession...

Methanogenic degradation of crude oil in subsurface sediments occurs slowly, but without the need for exogenous electron acceptors, is sustained for long periods and has enormous economic and environmental consequences. Here we show that volatile hydrocarbons are inhibitory to methanogenic oil biodegradation by comparing degradation of an artificially weathered crude oil with volatile hydrocarb...

Conflicts over reproductive division of labour are common in social insects. These conflicts are often resolved via antagonistic actions that are mediated by chemical cues. Dominant egg layers and their eggs can be recognized by a specific yet similar cuticular hydrocarbon profile. In the facultatively queenless ant Gnamptogenys striatula, a worker's cuticular hydrocarbon profile signals its fe...

Labial gland secretions of 22 males of the bumblebee Bombus pomorum, collected in the Czech Republic, were analysed separately for each individual. The secretions contained 70 compounds among which saturated and unsaturated hydrocarbons strongly dominated. The proportion of hydrocarbons in the secretion was unusually high (85-100%) compared to other bumblebee species studied so far (3-15%). Met...

Queens in many social insects are known to maintain their status through chemicals (pheromones) and cuticular hydrocarbons and have been the focus of many investigations that have looked at the chemicals involved in queen signaling. In the primitively eusocial wasp Ropalidia marginata Lepeletier (Hymenoptera: Vespidae), the Dufour's gland has been shown to be involved in queen signaling, and Du...