PSA-stage Features of the Hybrid Membrane-sorption Oxygen Concentrator

The paper considers the principle of the organization of the hybrid membranesorption oxygen concentrator and the work of the PSA stage of the hybrid system. The use of hybrid membrane-sorption gas separation systems can significantly reduce the energy consumption of plants, as well as to neutralize such disadvantages as contamination of the product flow by the products of abrasion of sorbents, through the use of highly selective polymer membrane, and the restriction on the oxygen concentration when using a single membrane stage, through its use after the PSA stage. In this paper, we propose an arrangement for the operation of the PSA stage of a hybrid system consisting of three adsorbers and providing a constant product flow of the PSA stage necessary to ensure continuous feed flow to the membrane stage of the system. Each of the adsorbers in this system passes through three main stages: filling, displacement (adsorption), and discharge (desorption). Moreover, the filling is not from the compressor, but part of the product flow of the displaced adsorber. The results of the operation of the system organized by the proposed method are compared with the results of the operation of modern gas separation systems on the market.     Keywords: Sorption, air separation, pressure-swing adsorption, PSA, hybrid technologies, oxygen concentrator, recycling, oxyge

ИССЛЕДОВАНИЕ МАТЕРИАЛОВ ДЛЯ ИК–ЛАЗЕРОВ НА ОСНОВЕ ПОЛУПРОВОДНИКОВ AIIBVI, ЛЕГИРОВАННЫХ ИОНАМИ Fe2+

It well−known that optical fibers have a «window of transparency » (1.5−3 µm) which is much wider than the spectra of the transmitted signals. For this reason there is some potential in transmitting signals using different, previously unused frequencies, in order to increase the economic efficiency of existing and new optical fiber lines. This may be the origin of the great interest to research into the creation of А2В6 and А3В5 semiconductor lasers doped with Cr2+, Co2+, Ni2+, Fe2+ and rare earth element ions. Theoretical and experimental studies in this field are usually focused on one type of semiconductor doped with one type of ion. With the appearance of the general theory of ligand structure environment of iron group ions (Co2+, Ni2+ and Fe2+) there is now a way to calculate the full matrix of luminescence parameters of iron group ions for the entire group of А2В6 semiconductors, in addition to conventional research methods. The results of research for Fe2+ ions in А2В6 semiconductors are presented in this paper. Полоса прозрачности волоконно− оптических линий связи (ВОЛС) в диапазоне длин волн 1,5—3 мкм значительно шире спектров передаваемых сигналов. Для повышения экономической эффективности построенных и новых ВОЛС перспективно применение передачи сигналов на новых, еще не использованных частотах. С этим, возможно, связан интерес к исследованиям по созданию лазеров на полупроводниках АIIВVI и АIIIВV, легированных ионами Cr2+, Co2+, Ni2+ и Fe2+ и редкоземельных элементов. Ранее исследования в этом направлении выполняли на отдельном типе полупроводника, легированного одним из ионов. C появлением общей теории лигандной структуры окружения ионов группы железа (Co2+, Ni2+ и Fe2+) появилась возможность рассчитать весь набор параметров областей люминесценции ионов группы железа в полупроводниках АIIВVI, в дополнение к более традиционным способам исследований. Приведены результаты расчета параметров массива областей люминесценции для ионов Fe2+ в полупроводниках АIIВVI. Показано, что полученные расчетные значения спектральных областей люминесценции совпадают со значениями, определенными экспериментально другими авторами, что подтверждает правильность выбранного метода расчета. Полученные результаты позволяют целенаправленно выбирать из всего рассчитанного массива переходов в материалах AIIBVI, легированных Fe2+, наиболее подходящие для создания ИК−лазеров с требуемыми значениями длины волны и спектральных характеристик излучения, перестраиваемых в широком диапазоне длин волн.

Calculation of strain-stress state of flywheel in potential field

© 2015 D.V. Berezhnoi et al. This paper focuses on strain-stress state of the flywheel in the kinetic energy storage. The flywheel kinetic storage is based on the flywheel-housing scheme in potential field, at the quasistatic increase of rotor velocity. It is particularly noteworthy that a potential field in flywheel-housing system allows to increase specific energy capacity of energy storage

Measurement of ϒ production in pp collisions at √s = 2.76 TeV

The production of ϒ(1S), ϒ(2S) and ϒ(3S) mesons decaying into the dimuon final state is studied with the LHCb detector using a data sample corresponding to an integrated luminosity of 3.3 pb−1 collected in proton–proton collisions at a centre-of-mass energy of √s = 2.76 TeV. The differential production cross-sections times dimuon branching fractions are measured as functions of the ϒ transverse momentum and rapidity, over the ranges pT < 15 GeV/c and 2.0 < y < 4.5. The total cross-sections in this kinematic region, assuming unpolarised production, are measured to be σ (pp → ϒ(1S)X) × B ϒ(1S)→μ+μ− = 1.111 ± 0.043 ± 0.044 nb, σ (pp → ϒ(2S)X) × B ϒ(2S)→μ+μ− = 0.264 ± 0.023 ± 0.011 nb, σ (pp → ϒ(3S)X) × B ϒ(3S)→μ+μ− = 0.159 ± 0.020 ± 0.007 nb, where the first uncertainty is statistical and the second systematic