On the evaporation dynamics of trinitrotoluene microparticles on the glass surface

The results of measuring the time dependence of the concentration of trinitrotoluene (TNT) vapor over its solid microconcentrations on the glass surface with a low TNT concentration on the surface of 100 ng/cm2 are presented. Such microconcentrations of traces are typical for the conditions of anti-terrorist control of objects for the presence of TNT. The measurements were made using a portable multicapillary gas chromatograph (GC) EKHO-V-IDTS (Russia) with TNT vapor concentration. The threshold for determining the concentration of TNT vapor by the EKHO-V-IDTS gas chromatograph corresponds to the modern level and is equal to 10-14 g/cm3. Vapor sampling is performed by a vortex sampling device (VSD), which is used in the anti-terrorist control of objects. It is shown that the initial surface concentration of TNT traces of 100 ng/cm2 on the glass surface decreases to 12 ng/cm2 in a time of 2.6 h due to evaporation into an open half-space under laboratory conditions. The vapor concentration over the residual TNT concentration of 12 ng/cm2 corresponds to the GC sensitivity threshold for TNT vapor concentration equal to 10-14 g/cm3

ВВОД ПРОБЫ АРОМАТИЧЕСКИХ СОЕДИНЕНИЙ С КОНЦЕНТРАТОРОВ В ПОЛИКАПИЛЛЯРНУЮ КОЛОНКУ МЕТОДОМ ТЕРМИЧЕСКОЙ ДЕСОРБЦИИ

At present, there is an increased interest in geochemical methods of searching for hydrocarbon deposits by detecting on the Earth's surface the scattering halos of hydrocarbons that migrated from those deposits, namely the aromatic hydrocarbons such as benzene, toluene, xylenes. The concentrations of the migrated hydrocarbons on the surface of the Earth are usually low and could only be detected at the threshold level of the gas analyzers. Therefore, for their registration, the preconcentration is applied, in particular, the passive preconcentration. For this purpose, the concentrators are used, which are laid at shallow depths in the explored area. The survey technology that is being developed by the authors uses the reusable concentrators in the form of hollow stainless-steel tubes with SE-30 siloxane-based sorbent applied on their inner surface. The concentrators placed in the analytical containers are laid in the ground for 1-2 days. The analysis of the samples from the concentrators is carried out on a portable multicapillary gas chromatograph in the field conditions. The current article is devoted to the development of a special device for the sample injection from the passive concentrators and the experimental determination of the optimal mode of thermal desorption sample injection from the concentrators into the multicapillary column. The original injection scheme is given, where the gas-dynamic isolation of the injection device camera and the multicapillary column during the concentrator heating and sample analysis is implemented; the optimum concentrator heating time and the optimum sample injection time are determined.Keywords: passive concentrators, thermal desorption sample injection, gas-dynamic isolation of the injection device and columnDOI: http://dx.doi.org/10.15826/analitika.2019.23.3.003(Russian)V.M. Gruznov1,2,3, M.N. Baldin1, A.O. Malysheva1,3 1Trofimuk Institute of Petroleum Geology and Geophysics of Siberian Branch of Russian Academy of Sciences, Koptug Avenue, 3, Novosibirsk, 630090,Russian Federation2Novosibirsk State University, Pirogova St., 2, Novosibirsk, 630090, Russian Federation3Novosibirsk State Technical University, Prospekt K. Marx Avenue, 20, Novosibirsk, 630073, Russian FederationВ настоящее время возрос интерес к геохимическим методам поиска залежей углеводородов по выявлению на поверхности Земли ореолов углеводородов, мигрирующих из залежей, в частности ароматических углеводородов: бензола, толуола, ксилолов. Концентрации мигрирующих углеводородов на поверхности Земли, как правило низкие, и находятся на уровне пороговых значений для газоаналитических приборов. Поэтому для их регистрации применяют концентрирование, в частности пассивное. Для этого используют концентраторы, закладываемые на небольшие глубины на разведываемой площади. В технологии съёмки, разрабатываемой авторами, используются многоразовые концентраторы в виде полых трубок из нержавеющей стали с сорбентом на основе силоксана SE-30, нанесенного на внутреннюю поверхность. Концентраторы в аналитических контейнерах закладываются в грунт на 1-2 суток. Анализ проб с концентраторов осуществляется на портативном поликапиллярном газовом хроматографе в полевых условиях. Статья посвящена специальному устройству ввода пробы с пассивных концентраторов и экспериментальному определению оптимального режима термодесорбционного ввода пробы с концентраторов в поликапиллярную колонку. Приведена оригинальная схема ввода, в которой реализована газодинамическая изоляция камеры устройства ввода и поликапиллярной колонки во время нагрева концентратора и анализа пробы, определено оптимальное время нагревания концентраторов и время ввода пробы.Ключевые слова: пассивные концентраторы, ввод методом термической десорбции, газодинамическая изоляция устройства ввода и колонкиDOI: http://dx.doi.org/10.15826/analitika.2019.23.3.00

Collective behaviour of partons could be a source of energetic hadrons

We discuss the idea that collective behaviour of the quarks/partons, which has been intensely discussed for the last 40 years in relativistic hadron-nuclear and nuclear-nuclear interactions and confirmed by new data coming from the ultrarelativistic heavy ion collisions, can lead to energetic particle production. Created from hadronization of the quark/parton (or quarks/partons), energetic particles could get the energy of grouped partons from coherent interactions. Therefore, we think that in the centre of some massive stars, a medium with high density, close to Quantum Chromodynamic one could be a source of the super high-energy cosmic rays.Comment: 8 pages, 8 figure

Clustering in light nuclei in fragmentation above 1 A GeV

The relativistic invariant approach is applied to analyzing the 3.3 A GeV $^{22}$Ne fragmentation in a nuclear track emulsion. New results on few-body dissociations have been obtained from the emulsion exposures to 2.1 A GeV $^{14}$N and 1.2 A GeV $^{9}$Be nuclei. It can be asserted that the use of the invariant approach is an effective means of obtaining conclusions about the behavior of systems involving a few He nuclei at a relative energy close to 1 MeV per nucleon. The first observations of fragmentation of 1.2 A GeV $^{8}$B and $^{9}$C nuclei in emulsion are described. The presented results allow one to justify the development of few-body aspects of nuclear astrophysics.Comment: 7 pages, 8 figures, 3 tables, Nuclear Physics in Astrophysics-2, 16-20 May, 2005 (ATOMKI), Debrecen, Hungar