A detailed composition, intensity and temperature dependent photoluminescence (PL) study of CuInSe 2 has been performed to obtain data on defects, directly comparable to the defects in CuGaSe 2 , prepared under the same conditions. Epitaxial films are grown by metal organic vapour phase epitaxy on GaAs. The PL study reveals three shallow defects, which are responsible for the doping behaviour in CuInSe 2 : two acceptors, 40 and 60 meV deep, and a donor, approximately 12 meV deep. The shallower acceptor dominates for low or no Cu-excess, whereas the deeper one dominates material grown under high Cuexcess. These defects and their compositional dependence are the same as observed in CuGaSe 2 . Thus no fundamental difference concerning the shallow defects exists between these two materials.
The possibilities of using dual-pulse laser atomic-emission spectroscopy for both the estimation of elemental concentrations in bronzes and layer-by-layer analysis of a bronze coating on steel bead wire have been examined. Two methods have been proposed to lower the radiation flux density q in studies of thin metallic layers. These were based respectively on using optical filters and defocusing the radiation with respect to a sample surface. It has been found that the decrease of q results in reducing the influence of tin on copper evaporation under dual-pulse laser irradiation.Introduction. Laser-induced breakdown spectroscopy (LIBS) is a method of qualitative and quantitative analysis that is based on recording emission spectra of laser-induced plasma. It depends fundamentally on the interaction of powerful optical radiation with a sample surface that produces heat, melting, vaporization, and atomization of a substance and formation of ablation plasma. One of the most rapidly developing areas of LIBS that can increase significantly the intensity of the spectral lines and, therefore, the analytical sensitivity is the use of dual laser pulses (DLP) that are phase-shifted relative to each other as the excitation source for the spectra [1, 2]. The principal reason for the increase of optical emission is the formation of a region near the surface with increased temperature and particle density. Furthermore, heating of the sample by the first pulse and the additional excitation of atoms in the initial plasma by the second pulse are also responsible for the strengthening of the analytical signal.The advantages of LIBS are the highly localized sampling area; the small amounts of substance vaporized by the radiation; the weak dependence of the ablation process on the sample physicochemical properties; and ability to use untreated surfaces. Because of these advantages, LIBS is used to analyze various objects such as industrial raw materials and finished products, minerals and soils, and biological objects [3][4][5].LIBS of bronzes has been the subject of several theoretical and experimental studies [6][7][8]. However, the attention in most of these was focused on quantitative analysis of works of art [6] or objects located under water [7]. Yet bronzes are rather common construction materials that are used to fabricate massive items and as coatings on steel wire in order to protect it and improve the adhesion of the surface to resin. LIBS studies of thin metal layers involved primarily single-component coatings such as galvanized iron [9] and copper deposited on steel boiler pipes [10]. The requirements imposed on the excitation source of the spectrum are different for analyzing works of art and industrial products made of bronze. In the first instance, it is very important to minimize surface damage by the laser radiation; in the second, to minimize the determination error of element concentrations to the corresponding GOST level. This is usually achieved by using multiple surface excitations.The goal of our work was to ...
and A. I. KomyakThe effects of several metal cations and anions on complexation of tetra-and pentavalent uranium in an acetone solution of UO 2 (ClO 4 ) 2 ·5H 2 O irradiated by an LED (420-440 nm) were studied using electronic absorption. It was shown that addition of background components to the solution had an insignifi cant effect on complexation of the lowest-valent uranium. The composition of the 2+ 2 UO coordination sphere could change at a certain irradiation time (>90 min) but the system as a whole was maintained.Introduction. Radioactive wastes are always formed during operation of nuclear power plants. Reprocessing of spent nuclear fuel requires its dissolution in acids and multiple operations with solutions including the purifi cation of liquid radioactive wastes (LRW). Such solutions contain not only radioactive elements (uranium and transuranium elements) but also several stable decay products. The processing solutions also contain large amounts of background metals, e.g., K, Na, Mg, Ca, Al, etc., and several anions, primarily
Рецензирование статей осуществляется на основании Положения о рецензировании статей и материалов для опубликования в Межвузовском сборнике научных трудов «Физико-химические аспекты изучения кластеров, наноструктур и наноматериалов». Официальный сайт издания в сети Интернет: https://www.physchemaspects.ru Ф50 Физико-химические аспекты изучения кластеров, наноструктур и наноматериалов [Текст]. Тверь: Твер. гос. ун-т, 2019. Вып. 11. 680 с. Зарегистрирован Федеральной службой по надзору в сфере связи, информационных технологий и массовых коммуникаций, свидетельство о регистрации СМИ ПИ № ФС 7747789 от 13.12.2011. Издание составлено из оригинальных статей, кратких сообщений и обзоров теоретического и экспериментального характера, отражающих результаты исследований в области изучения физико-химических процессов с участием кластеров, наноструктур и наноматериалов физики, включая межфазные явления и нанотермодинамику. Сборник предназначен для научных и инженерно-технических работников, преподавателей ВУЗов, студентов и аспирантов. Издание подготовлено на кафедре общей физики Тверского государственного университета. Переводное название: Physical and chemical aspects of the study of clusters, nanostructures and nanomaterials Транслитерация названия: Fiziko-himičeskie aspekty izučeniâ klasterov, nanostruktur i nanomaterialov
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