The catalytic methanolysis of the chemical warfare nerve agents soman, sarin, and VX was investigated by using Cu or Zn complexes. Although VX withstood decontamination, the decomposition yield being around 96%, the soman and sarin deposited on different surfaces were almost fully destroyed under ambient conditions. The catalytic tests performed on a wide range of contaminated surfaces confirm the activity of the investigated catalytic systems, these complexes being suitable, from an economical point of view, for use in the formulation of a possible decomposition kit with military or civilian applicability. 相似文献
Mikanolide [systematic names: 1,10:2,3‐diepoxy‐6,8‐dihydroxy‐11‐vinylgermacr‐4‐ene 12,14‐di‐γ‐lactone and 7,10a‐dimethyl‐1a,1b,2a,6a,7,9a,10,10a‐octahydro‐4H‐6,3‐methenofuro[3,2‐c]bisoxireno[f,h]oxacycloundecin‐4,8(6H)‐dione], C15H14O6, derived from a variety of Mikania micrantha growing in Portland, Jamaica, contains a methylcyclodecane ring fused to an unsaturated planar α,γ‐lactone, an envelope‐type near‐planar vinyl‐β,γ‐lactone and two epoxide moieties. The crystal packing shows stacks of mikanolide molecules interlocked via a network of non‐classical C—H⋯O hydrogen bonds between the lactone units. 相似文献
Rare-earth metal chelates used as fluorescent labels for immunoassays possess extremely long fluorescence lifetimes and permit the elective use of time-resolved detection. This is very important in fiber-optic fluorimetry, a technique that ordinarily exhibits large signal backgrounds from back-scattered radiation. With time-resolved detection to reject the back-scattered radiation, the limit of detection for Eu 2-naphthoyltrifluoroacetonate is 10(-12)M, nearly three orders of magnitude lower than for the fiber-optic measurement of the most common fluorescent label, fluorescein isothiocyanate. Commercially available reagents labeled with an europium chelate are used to demonstrate the potential utility of time-resolved fluorimetry in fiber-optic immunoassays. Rabbit immunoglobulin G (IgG) is covalently bonded to the distal end of quartz optical fibers prior to exposure to anti-rabbit IgG labelled with europium chelate. The limit of detection for the assay is approximately 0.1 mug/ml. 相似文献
New efficient depollution techniques for water decontamination, purification and disinfection are being sought to replace those classic methods (chemical, filtration, ozonisation, photochemical reactions) that have deficiency for some substances. The use of plasma technologies, discharges in, or in contact with, wastewater are promising approaches for the decomposition of pollutants by highly oxidative radicals, charged particles, UV radiation, etc. produced by plasma. In the present study we report on the potential of radiofrequency single and multiple filamentary Dielectric Barrier Discharge (DBD) jets for the decolorization of methylene blue (MB) dye in water solutions. Optical emission spectroscopy (OES) investigations were performed for the characterization of plasma evolving in air, and in liquid. The decolorization process was monitored by absorption spectroscopy. We determined the decolorization time, according to a variety of external parameters. The key parameters for obtaining the maximum decolorization rate were identified as being the discharge tube diameter, tube nature (glass/ceramic), the injected power in the discharge, the type of reactive gas and the number of filamentary plasma jets.
Several species belonging to the Hyptis (Lamiaceae) genus represent an important source of bioactive constituents, which are reputed for their wide range of antimicrobial, anticancer and insecticidal activities. The volatile oils obtained from various parts of the Hyptis plants were found to be primarily composed of mono- and sesquiterpenes. Significant differences were observed in the percentage compositions of the major components, which allowed for differentiation among the species. Based on the dominant constituents, phylogenetic relationships were found to be common among some species: 1,8-cineole (H. fruticosa, H. goyazensis, H. martiusii and H. suaveolens); beta-caryophyllene (H. marrubioides, H. pectinata, H. spicigera and H. suaveolens); eugenol (H. recurvata and H. suaveolens); gamma-cadinene (H. glomerata and H. ovalifolia); p-cymene (H. mutabilis and H. pectinata); alpha-pinene (H. crenata and H. emoryi). The monoterpenes, alpha-pinene and p-cymene were detected at various concentrations in all the Hyptis oils investigated. This paper reviews the essential oil compositions of eighteen Hyptis plant species studied in various parts of the world covering the publications of 100 years (1909 to 2009) after the first article appeared in the literature. 相似文献