Главная
Авторизация
Фамилия
Пароль
 

Базы данных


Труды сотрудников ИФ СО РАН - результаты поиска

Вид поиска

Область поиска
в найденном
 Найдено в других БД:Каталог книг и брошюр библиотеки ИФ СО РАН (6)
Формат представления найденных документов:
полный информационныйкраткий
Отсортировать найденные документы по:
авторузаглавиюгоду изданиятипу документа
Поисковый запрос: (<.>K=Crystallization<.>)
Общее количество найденных документов : 35
Показаны документы с 1 по 10
 1-10    11-20   21-30   31-35 
1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Hu T., Ning L., Gao Y., Qiao J., Song E., Chen Z., Zhou Y., Wang J., Molokeev M. S., Ke X., Xia Z., Zhang Q.
Заглавие : Glass crystallization making red phosphor for high-power warm white lighting
Место публикации : Light Sci. Appl. - 2021. - Vol. 10, Is. 1. - Ст.56. - ISSN 20955545 (ISSN), DOI 10.1038/s41377-021-00498-6
Примечания : Cited References: 50. - The present work was supported by the National Natural Science Foundations of China (Grant Nos. 51972118, 51961145101, 51722202 and 11974022), the Guangzhou Science & Technology Project (202007020005), the Fundamental Research Funds for the Central Universities (D2190980), and the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program (2017BT01X137)
Аннотация: Rapid development of solid-state lighting technology requires new materials with highly efficient and stable luminescence, and especially relies on blue light pumped red phosphors for improved light quality. Herein, we discovered an unprecedented red-emitting Mg2Al4Si5O18:Eu2+ composite phosphor (λex = 450 nm, λem = 620 nm) via the crystallization of MgO–Al2O3–SiO2 aluminosilicate glass. Combined experimental measurement and first-principles calculations verify that Eu2+ dopants insert at the vacant channel of Mg2Al4Si5O18 crystal with six-fold coordination responsible for the peculiar red emission. Importantly, the resulting phosphor exhibits high internal/external quantum efficiency of 94.5/70.6%, and stable emission against thermal quenching, which reaches industry production. The maximum luminous flux and luminous efficiency of the constructed laser driven red emitting device reaches as high as 274 lm and 54 lm W−1, respectively. The combinations of extraordinary optical properties coupled with economically favorable and innovative preparation method indicate, that the Mg2Al4Si5O18:Eu2+ composite phosphor will provide a significant step towards the development of high-power solid-state lighting.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Коржнева, Ксения Евгеньевна, Исаенко Л. И., Елисеев, Александр Павлович, Молокеев, Максим Сергеевич
Заглавие : Экспериментальное исследование процессов кристаллизации K2Ba(NO3)4 из раствор-расплава
Место публикации : Фундамент. пробл. совр. материаловед. - 2018. - Т. 15, № 1. - С. 11-15. - ISSN 1811-1416, DOI 10.25712/ASTU.1811-1416.2018.01.001
Примечания : Библиогр.: 7. - Работа выполнена в рамках государственного задания, проект № 0330 - 2016 - 0008 и при поддержке Российского фонда фундаментальных исследований (грант № 18-32-00359).
Ключевые слова (''Своб.индексиров.''): рост из раствор-расплава--двойные соединения--нецентросимметричные кристаллы k2ba(no3)4--рентгенофазовый и термический анализы--оптическое пропускание--growth from solution-melt--double compounds--noncentrosymmetrical crystals k2ba(no3)4--x-ray diffraction and thermal analysis--optical transmittance
Аннотация: С развитием технологий неуклонно возрастает потребность в высокоэффективных функциональных материалах. Поэтому все более важной и актуальной становится задача разработки принципов и алгоритмов поиска этих материалов. В настоящее время системы двойных нитратов привлекают внимание исследователей тем, что в этой группе существуют двойные соединения с нецентросимметричной структурой, которые рассматриваются как перспективные нелинейные материалы для коротковолнового диапазона. В результате проведенных ранее исследований из водных растворов были получены кристаллы K2Ba(NO3)4. Было выявлено, что K2Ba(NO3)4 при температуре 197,3 оС разлагается на KNO3 и Ba(NO3)2. Из-за большого количества дефектов (дендриты, зарастание основными гранями роста) оптическое качество этих кристаллов оказалось невысоким. Что обусловило необходимость поиска новых методик выращивания, обеспечивающих получение качественных оптически прозрачных кристаллов. Поэтому нами исследовались процессы кристаллизации K2Ba(NO3)4 из раствор-расплава. Подобран растворитель состава LiNO3-CsNO3-KNO3 с температурой эвтектик ниже температуры разложения двойного соединения. Выращены прозрачные кристаллы K2Ba(NO3)4 размером до 0,7 мм, определена их структура, показано отсутствие у них центра симметрии. На данных кристаллах были сняты спектры оптического пропускания. Исследование двух спектров данного соединения выращенного разными методами показало, что кристаллы, полученные из водных растворов, прозрачен от 0,25 мкм до 2,2 мкм, при этом наблюдается пик поглощения с максимум 0,3 мкм. Кристаллы, выращенные методом из раствор-расплава, прозрачны от 0,3 мкм до 2,2 мкм. Ширина запрещенной зоны составляет около 5 эВ.With the development of technology, the need for highly efficient functional materials is steadily increasing. Therefore, the developing of principles and algorithms for these materials' search becomes more and more important and actual. Currently systems of double nitrates attract researchers attention due to the double compounds with a noncentrosymmetric structure which are considered as promising nonlinear materials for the short-wave range. As a result of previous studies K2Ba(NO3)4 crystals were obtained from aqueous solutions. It was found that K2Ba(NO3)4 decomposes on KNO3 and Ba(NO3)2 at the temperature of 197.3 oC. Due to the large amount of defects (dendrites, overgrowing by the main growth facets), the optical quality of these crystals was not high. This necessitated the search for new growth techniques that provide the production of high-quality optically transparent crystals. Therefore, we investigated the processes of crystallization of K2Ba(NO3)4 from a solution-melt. A solvent of the LiNO3-CsNO3-KNO3 composition with a eutectic temperature below the decomposition temperature of the double compound was chosen. Transparent crystals of K2Ba(NO3)4 up to 0.7 mm in size were grown, their structure was determined, and the absence of center of symmetry was shown. The optical transmission spectra were investigated on these crystals. The study of two spectra of this compound grown by different methods showed that crystals obtained from aqueous solutions are transparent from 0.25 μm to 2.2 μm, with an absorption peak with a maximum of 0.3 μm. Crystals grown by the solution-melt method are transparent from 0.3 μm to 2.2 μm. The width of the band gap is about 5 eV.
Смотреть статью,
РИНЦ,
Читать в сети ИФ
Найти похожие
3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Гаврилюк, Анатолий Петрович, Исаев, Иван Леонидович, Карпов, Сергей Васильевич, Герасимов, Валерий Сергеевич
Заглавие : Электронный туннельный эффект и особенности кристаллизации наноразмерных золей металлов
Место публикации : Инженерная физика. - Москва: Общество с ограниченной ответственностью Издательство Научтехлитиздат, 2009. - № 2. - С. 51-53. - ISSN 2072-9995
Предметные рубрики:
Ключевые слова (''Своб.индексиров.''): nano particles--наночастицы--tunnel effect--bimodal bands--туннельный эффект--бимодальный ансамбль
Аннотация: Исследуются закономерности самоорганизации бимодальных ансамблей наночастиц в кристаллические структуры в лиозолях металлов (на примере органозолей золота) методом броуновской динамики. Показана возможность селективной коагуляции разно-размерных частиц вследствие асимметрии встречных туннельных электронных потоков межу частицами разных размеров и их взаимного разнополярного заряжения; исследуется кинетика этого процесса.Explored conformity to the law organizations of bimodal bands of nano particles in crystalline structures in liozole metals (for example of organozole gold) by the method of brownian dynamics. Possibility of selective coagulation of particles of different-sizes is shown because of asymmetry of meetings tunnel electronic streams boundary path by the particles of different sizes and their mutual different arctic loading; explored kinetics of this process.
РИНЦ
Найти похожие
4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zaitsev A. I., Zamkov A. V., Molokeev M. S., Cherepakhin A. V., Koroleva N. S.
Заглавие : Phase formation upon crystallization of SrO center dot 2B(2)O(3) glasses
Место публикации : Crystallogr. Rep. - NEW YORK: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2011. - Vol. 56, Is. 1. - С. 44-51. - JAN. - ISSN 1063-7745, DOI 10.1134/S1063774511010263
Примечания : Cited Reference Count: 21
Предметные рубрики: STRONTIUM TETRABORATE
LUMINESCENCE
SRB4O7
GROWTH
Ключевые слова (''Своб.индексиров.''): crystalline form--crystalline formation--crystalline phasis--glass surfaces--phase formations--thermal analysis--thermal stability--crystalline materials--crystallization--glass--thermoanalysis--thermodynamic stability--metastable phases
Аннотация: The crystallization of SrO center dot 2B(2)O(3) glasses has been studied. Four different crystalline formations were found to form simultaneously and independently on the glass surface: stable alpha-SrB4O7 crystals and metastable crystalline forms (beta-SrB4O7, Sr4B14O25, and spherulites (presumably, mixtures of crystalline phases)). The ranges of thermal stability of the newly formed metastable phases have been established using thermal analysis.
WOS,
Scopus,
eLibrary
Найти похожие
5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ji H., Wang L., Cho Y., Hirosaki N., Molokeev M. S., Xia Z., Huang Z., Xie R.-J.
Заглавие : New Y2BaAl4SiO12:Ce3+ yellow microcrystal-glass powder phosphor with high thermal emission stability
Место публикации : J. Mater. Chem. C: Royal Society of Chemistry, 2016. - Vol. 4, Is. 41. - P.9872-9878. - ISSN 20507534 (ISSN), DOI 10.1039/c6tc03422e
Примечания : Cited References: 32. - This study was partially supported by the National Natural Science Foundation of China (Grant No. 51272259, 51572232 and 51561135015). R. X. was also partially supported by the JSPS KAKENHI (No. 15K06448). M. M. and Z. X. were also partially supported by the Russian Foundation for Basic Research (No. 15-52-53080). H. J. thanks the China Scholarship Council (CSC) for scholarship support.
Ключевые слова (''Своб.индексиров.''): aluminum--crystal structure--crystallization--glass--laser applications--light emission--microcrystals--phosphors--precipitation (chemical)--quenching--silicon--silicon oxides--single crystals--structural design--crystalline nature--crystallization behavior--emission intensity--microcrystal glass--morphology structures--phase formation behavior--structure analysis--temperature increase--cerium
Аннотация: To decrease the rare earth element usage and synthesis cost of Y3Al5O12:Ce phosphor, the Y2BaAl4SiO12 compound is developed as a new host for Ce3+ employing the solid solution design strategy. The design uses polyhedron substitution where YO8/AlO4 are partially replaced by BaO8/SiO4, respectively. Structure analysis of Y2BaAl4SiO12 proves that it successfully preserves the garnet structure, crystallizing in the cubic Iad space group with a = b = c = 12.00680(5) Å. Barium (Ba) atoms occupy the Y site and silicon (Si) atoms occupy the Al site in the AlO4 tetrahedrons. An expanded study on Y2MAl4SiO12 (M = Ba, Ca, Mg, Sr) series shows a cation size (of M)-dependent phase formation behavior. The lattice stability can be related with the M type in the M–Si pair and substitution level of M–Si for Y–Al. Doping Ce3+ into Y2BaAl4SiO12 yields bright yellow photoluminescence peaking at around 537 nm upon excitation by 460 nm light. The emission intensity is quite stable against thermal quenching whereas the peak wavelength shows a slight red-shift as the ambient temperature increases. The crystallization behavior of Y2BaAl4SiO12 is suggested as melt-assisted precipitation/growth based on cathodoluminescence analysis. The highly crystalline nature of the microcrystals explains the stable emission against thermal quenching. This study may provide an inspiring insight into preparing phosphor with new morphology-structure of “microcrystal-glass powder phosphor”, which distinguishes it from conventional “ceramic powder phosphor” or “single-crystal phosphor”.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : NESTEROV A. I., Ovchinnikov S. G.
Заглавие : ACOUSTIC-WAVE AMPLIFICATION IN FAST CRYSTALLIZATION
Место публикации : Fiz. Tverd. Tela: MEZHDUNARODNAYA KNIGA, 1988. - Vol. 30, Is. 1. - P184-186. - ISSN 0367-3294
Примечания : Cited References: 14
WOS
Найти похожие
7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Wang, Xuejiao, Molokeev M. S., Zhu, Q.i., Li, Ji-Guang
Заглавие : Controlled hydrothermal crystallization of anhydrous Ln2(OH)4SO4 (Ln = Eu-Lu, Y) as a new family of layered rare earth metal hydroxides
Место публикации : Chem. - A Eur. J. - 2017. - Vol. 23, Is. 63. - P.16034-16043. - ISSN 0947-6539, DOI 10.1002/chem.201703282. - ISSN 1521-3765(eISSN)
Примечания : Cited References:54. - This work is supported in part by the National Natural Science Foundation of China (Grants Nos. 51702020, and 51672039), Doctoral Research Fund of Liaoning Province (Grant No. 20170520103) and the Russian Foundation for Basic Research (17-52-53031). X.W. acknowledges the financial support from the China Scholarship Council for her overseas Ph.D. study (Contract No. 201406080035).
Предметные рубрики: ANION-EXCHANGE MATERIALS
BOND-VALENCE PARAMETERS
X-RAY-DIFFRACTION
Ключевые слова (''Своб.индексиров.''): hydrothermal synthesis--layered compounds--luminescence--oxide sulfates--rare earths
Аннотация: Anhydrous hydroxide sulfates Ln2(OH)4SO4 (Ln=Eu–Lu, Y) were hydrothermally synthesized as a new family of layered rare earth metal hydroxides (LRHs). They crystallize in the monoclinic system (space group C2/m) with structures built up by alternate stacking of interlayer SO42− and the two-dimensional host layer composed of tricapped [LnO9] trigonal prisms along the a axis. In distinct contrast to the recently discovered hydrated LRHs Ln2(OH)4SO4⋅2 H2O, which only exist for Ln=La–Dy, the host layers of the anhydrous phase are linked together by sharing edges instead of an O node of the SO42− tetrahedron. Rietveld refinement showed that the cell dimension tends to decrease for smaller Ln3+, while the axis angle (β=98.78–100.31°) behaves oppositely. Comparative thermogravimetric/differential thermal analysis in air revealed that the dehydroxylation and desulfurization temperatures become gradually higher and lower, respectively, for smaller Ln3+, and thus the temperature range of Ln2O2SO4 existence is narrowed. The newly discovered Ln2(OH)4SO4, together with their hydrated counterparts, allow for the first time green synthesis of Ln2O2SO4 with water as the only exhaust for the full spectrum of lanthanides. Calcining Ln2(OH)4SO4 in H2 yielded phase-pure Ln2O2S for Eu and Gd and a mixture of Ln2O2S and Ln2O3 for the other Ln. The effects of the lanthanide contraction were clearly revealed, and photoluminescence was found for the anhydrous LRHs of Eu and Tb.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Wang X., Li J. -G., Molokeev M. S., Wang X., Liu W., Zhu Q., Tanaka H., Suzuta K., Kim B. -N., Sakka Y.
Заглавие : Hydrothermal crystallization of a Ln2(OH)4SO4·nH2O layered compound for a wide range of Ln (Ln = La-Dy), thermolysis, and facile transformation into oxysulfate and oxysulfide phosphors
Место публикации : RSC Adv.: Royal Society of Chemistry, 2017. - Vol. 7, Is. 22. - P.13331-13339. - ISSN 20462069 (ISSN), DOI 10.1039/c7ra00645d
Примечания : Cited References: 54. - This work was partly supported by the National Natural Science Foundation of China (Grants No. 51672039, 51172038, and 51302032), the Fundamental Research Fund for the Central Universities (Grant No. N140204002), the Grants-in-Aid for Scientific Research (KAKENHI No. 26420686), and the Russian Foundation for Basic Research (15-52-53080). Xuejiao Wang acknowledges the financial support received from the China Scholarship Council for her overseas Ph. D. study at the National Institute of Materials Science (Contract No. 201406080035).
Ключевые слова (''Своб.индексиров.''): dysprosium--hydrothermal synthesis--light emission--phase structure--phosphors--rare earth elements--acceleration voltages--chemical compositions--electron beam irradiation--hydrothermal conditions--hydrothermal crystallization--lanthanide contraction--photoluminescence properties--structure refinements--dysprosium compounds
Аннотация: The synthesis of a layered Ln2(OH)4SO4·nH2O material (Ln-241) with a smaller lanthanide ion (Dy3+) was successfully achieved through the optimization of the hydrothermal conditions, and the effect of lanthanide contraction on the chemical composition, phase structure, and crystallite/particle morphology of the products was investigated and discussed. Structure refinement showed that the lattice parameters (a, b, and c), cell volume, and axis angle across the series (Ln = La-Dy) monotonously decrease as the size of Ln3+ decreases. Comparative TG/DTA analysis in air indicated that the dehydroxylation temperature of Ln-241 tends to increase, whereas the dehydration and desulfurization temperatures decrease as the size of Ln3+ decreases, thus narrowing the stable temperature range for Ln2O2SO4. Taking advantage of the fact that Ln-241 has exactly the same Ln/S molar ratio as Ln2O2SO4 and Ln2O2S, the latter two groups of important compounds (excluding Ce) were facilely transformed from the former via the removal of water by calcination. The photoluminescence properties of Eu3+ and Tb3+, in terms of excitation, emission, fluorescence decay, quantum yield, and emission color, were investigated and compared for the two hosts Gd2O2S and Gd2O2SO4, and the (Gd0.99Tb0.01)2O2S phosphor was shown to be stable under electron beam irradiation in the studied range and exhibited an increasingly higher emission brightness as the acceleration voltage (up to 7 kV) or beam current (up to 50 μA) increased.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
9.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Vereshchagin S.N., Vereshchagina T.A., Solovyov L.A., Shishkina N.N., Vasilieva N.G., Anshits A.G.
Заглавие : Solid-phase transformation of Cs+- and Sr2+-bearing zeolite sorbents derived from cenospheres to mineral-like forms
Место публикации : Materials Research Society Symposium Proceedings. - 2009. - Vol. 1193: 32nd Symposium on Scientific Basis for Nuclear Waste Management (24 May 2009 through 29 May 2009, St. Petersburg, ) Conference code: 79940. - С. 87-94. - ISBN 02729172 (ISSN); 9781605111667 (ISBN)
Ключевые слова (''Своб.индексиров.''): apparent activation energy--cenospheres--crystalline minerals--crystalline phasis--crystallization temperature--higher temperatures--long-term disposal--multi phase systems--pollucites--principal components--solid-phase transformation--temperature range--thermal treatment--thermochemical transformations--transformation temperatures--xrd analysis--activation energy--atmospheric pressure--cesium--crystalline materials--crystallization--fly ash--metallic glass--radioactive waste disposal--radioactive wastes--silicate minerals--sodium--sorbents--sorption--strontium--synthesis (chemical)--waste management--atmospheric temperature
Аннотация: The paper describes the studies of the transformation of Cs+- and Sr2+-containing zeolite sorbents synthesized from fly ash cenospheres to crystalline mineral composition, suitable for the long-term disposal. Series of Cs+- and Sr2+-exchanged NaP1-containing sorbents were subjected to the thermochemical transformation in the temperature range 40-1100°C at atmospheric pressure in air and the progress of reaction was monitored by DSC and XRD analysis. It was shown that initial sodium zeolite undergoes two-step transformation at 736-785°C and 892-982°C forming nepheline as the principle product, with the conversion temperatures being dependant on the heating rate. The thermal treatment of Cs+-bearing zeolite sorbent led to formation of a complex multiphase system, the principal components of which were nepheline and pollucite. Increasing cesium content in the samples led to a monotonous shift of crystallization peak to the higher temperature range (1005-1006°C). A more complicated behavior was observed for Sr2+-containing samples, for which the crystallization temperature tends to increase (compared with NaP1) at lower Sr contents, but it starts decreasing parallel to the Sr2+ content at Sr2+ loadings 10 mg/g. The principal crystalline phases in Sr-NaP1 sample conversion were nepheline and Sr2+- containing feldspar, the quantity of which increased parallel to the increase of strontium content in zeolite. Apparent activation energies of thermochemical transformations were calculated and possible approaches to reduce transformation temperature are discussed and experimentally illustrated. © 2009 Materials Research Society.
Scopus,
eLibrary,
Источник статьи
Найти похожие
10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bezmaternykh L. N., Temerov V. L., Gudim I. A., Stolbovaya N.A.
Заглавие : Crystallization of trigonal (Tb,Er)(Fe,Ga)(3)(BO3)(4) phases with hantite structure in bismuth trimolybdate-based fluxes
Место публикации : Crystallogr. Rep. - 2005. - Vol. 50. - P.S97-S99. - ISSN 1063-7745, DOI 10.1134/1.2133981
Примечания : Cited Reference Count: 8
Предметные рубрики:
Аннотация: The stability regions of the trigonal (Tb,Er)(Fe,Ga)(3)(BO3)(4) phases are established in (Bi2Mo3O12)-based fluxes. The specific features of heterogeneous nucleation and the subsequent phase transformations during transition to the equilibrium are studied in the vicinity of the boundaries. The temperature modes of single crystal growth on seeds are suggested with due regard for the "nonequilibrium effect." (C) 2005 Pleiades Publishing, Inc.
WOS,
eLibrary,
Scopus
Найти похожие
 1-10    11-20   21-30   31-35 
 

Другие библиотеки

© Международная Ассоциация пользователей и разработчиков электронных библиотек и новых информационных технологий
(Ассоциация ЭБНИТ)