Simultaneous determination of 75 abuse drugs including amphetamines,benzodiazepines, cocaine,opioids, piperazines,zolpidem and metabolites in human hair samples using liquid chromatography–tandem mass spectrometry

A liquid chromatography–tandem mass spectrometric method for the simultaneous determination of 75 abuse drugs and metabolites, including 19 benzodiazepines, 19 amphetamines, two opiates, eight opioids, cocaine, lysergic acid diethylamide, zolpidem, three piperazines and 21 metabolites in human hair samples, was developed and validated. Ten‐milligram hair samples were decontaminated, pulverized using a ball mill, extracted with 1 mL of methanol spiked with 28 deuterated internal standards in an ultrasonic bath for 60 min at 50°C, and purified with Q‐sep dispersive solid‐phase extraction tubes. The purified extracts were evaporated to dryness and the residue was dissolved in 0.1 mL of 10% methanol. The 75 analytes were analyzed on an Acquity HSS T3 column using gradient elution of methanol and 0.1% formic acid and quantified in multiple reaction monitoring mode with positive electrospray ionization. Calibration curves were linear (r ≥ 0.9951) from the lower limit of quantitation (2–200 pg/mg depending on the drug) to 2000 pg/mg. The coefficients of variation and accuracy for intra‐ and inter‐assay analysis at three QC levels were 4.3–12.9% and 89.2–109.1%, respectively. The overall mean recovery ranged from 87.1 to 105.3%. This method was successfully applied to the analysis of 11 forensic hair samples obtained from drug abusers.     

Dielectric Spectroscopy as a Method for Testing Thin Vanadium Dioxide Films

Technical Physics - We have analyzed the dielectric spectra of thin (1200 Å) films of vanadium dioxide, a material with strong electron–electron correlations. We have tested both undoped...     

Effect of the modification of nanocrystalline MgO aerogels with vanadium and carbon on the destructive sorption of CF2Cl2 and CFCl3

The effect of the promotion of nanocrystalline MgO aerogels with small amounts of vanadium and carbon on the destructive sorption of the Freons CF₂Cl₂ and CFCl₃ was studied. It was found that the introduction of the promoters considerably shortened the induction period of the reaction. The pretreatment of samples modified with vanadium in an oxidizing or reducing atmosphere did not significantly affect the duration of the induction period. It was established that the acceleration of the reaction by fine-particle carbon did not depend on the mutual arrangement of carbon and MgO: on the surface of MgO nanoparticles, in the form of their mechanical mixture, or at separate positions in a reactor. It was concluded that the modifiers catalytically affect the interaction of MgO aerogels with Freons to accelerate the formation of active centers on the surface of their nanoparticles.     

Influence of the Ohmic Contact Structure on the Performance of GaAs/AlGaAs Photovoltaic Converters

A multilayer system of ohmic contacts for GaAs/AlGaAs photovoltaic converters has been developed. A method of ohmic contact blackening is suggested with the aim of improving the coefficient of optical signal reflection from an Ag/Au/Ag multilayer contact. Owing to blackening, the reflection coefficient has been decreased more than tenfold.     

Synthesis and analgesic activity of octahydro-2H-chromenols,derivatives of aliphatic ketones

Russian Chemical Bulletin - A series of compounds with a hydrogenated 2H-chromene skeleton was synthesized by the reaction of ketones and available para-menthane monoterpenoid (—)-isopulegol....     

Optical Stereoisomers of Geometric Isomers of the Octahedral Complex TiF4[Ph2P(O)CH2CH(OH)Me)]2 in CH2Cl2

Russian Journal of Coordination Chemistry - Some peculiarities of the effect of enantiomers of the monodentate ligand on the stereoisomerism of the mixed octahedral tetrafluoride complexes of...     

Transformations of several monoterpenoids in the presence of aldehydes in supercritical solvents

The reactivity of verbenol epoxide and isopulegol in supercritical solvents in the presence of aromatic aldehydes was studied using a flow type reactor and a heterogeneous catalyst (Al₂O₃) or no catalyst. The intramolecular transformations or interactions of reagents with the solvent prevailed in all cases; the yield of the products of intermolecular reactions of terpenoids with aldehydes was up to 1%. The aldehydes did not interact with verbenol epoxide but produced a considerable effect on the distribution of its isomerization products.     

A study on the evaluation of cesium removal performance in soil washing process using flocculating agent

Journal of Radioanalytical and Nuclear Chemistry - As a result of nuclear power plant accidents such as Chernobyl and Fukushima, and even their maintenance, the soil is contaminated due to the...     

Phosphorylation of Dienyl Diprenoid Alcohols

Abstract

The reactions of geraniol, nerol, and linalool with N,N-diethylamido O,O-propylenephosphite and diethyl chlorophosphite were studied. On the basis of these studies, new dienyl diprenoid phosphite esters were obtained.

GRAPHICAL ABSTRACT