Главная
Авторизация
Фамилия
Пароль
 

Базы данных


Труды сотрудников ИФ СО РАН - результаты поиска

Вид поиска

Область поиска
в найденном
Формат представления найденных документов:
полный информационныйкраткий
Отсортировать найденные документы по:
авторузаглавиюгоду изданиятипу документа
Поисковый запрос: (<.>K=cation<.>)
Общее количество найденных документов : 62
Показаны документы с 1 по 10
 1-10    11-20   21-30   31-40   41-50   51-60      
1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kartashev A. V., Flerov I. N., Gorev M. V., Mikhashenok N. V.
Заглавие : Effect of Isovalent Cation Substitution on the Thermal, Caloric, and Magnetocaloric Properties of the (La1 – yEuy)0.7Pb0.3MnO3 Manganites
Место публикации : Phys. Solid State. - 2019. - Vol. 61, Is. 1. - P.62-68. - ISSN 10637834 (ISSN) , DOI 10.1134/S1063783419010116
Примечания : Cited References: 27. - This study was supported by the Russian Foundation for Basic Research, the Government of the Kras-noyarsk Territory, and the Krasnoyarsk Territorial Foundation for Support of the Scientific and R&D Activity, project no. 17-42-240076 “Complex Approach to Searching and Development of Promising Solid-State Ferroic Cooling Agents Based on the Single-and Multicaloric Effects.” The authors thank M.S. Molokeev for structural characterization of the composites.
Аннотация: Crystalline samples of the (La1 – yEuy)0.7Pb0.3MnO3 (y = 0, 0.2, 0.4, 0.5, 0.6, and 0.8) manganite solid solutions have been grown. Temperature dependences of the specific heat, thermal expansion, and high-intensity magnetocaloric effect have been investigated. A comparative analysis of the effect of isovalent cationic substitution on the thermal and caloric parameters of the ferromagnetic phase transition has been made. It has been shown that the growth of the Eu atom concentration leads to a decrease in the phase transition entropy and an increase in the baric coefficient dT/dp. Field and temperature dependences of the magnetocaloric effect have been established. It is demonstrated that, varying the ratio of cations, one can obtain the solid solutions with the maximum magnetocaloric effect value in fields of up to 6 kOe in a temperature range of 90–340 K. Owing to the similar reduced relative cooling powers, the investigated solid solutions can be used as reference solid-state cooling media in designing the cascade cooling systems.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zhao M., Zhou Y., Molokeev M. S., Zhang Q., Liu Q., Xia Z.
Заглавие : Discovery of new narrow-band phosphors with the UCr4C4-related type structure by alkali cation effect
Место публикации : Adv. Opt. Mater. - 2019. - Vol. 7, Is. 6. - Ст.1801631. - ISSN 21951071 (ISSN) , DOI 10.1002/adom.201801631
Примечания : Cited References: 29. - This work was supported by the National Natural Science Foundations of China (Grant Nos. 51722202, 91622125, and 51572023) and Natural Science Foundations of Beijing (2172036). M.S.M. acknowledges the support of the Russian Foundation for Basic Research (No. 17-52-53031).
Ключевые слова (''Своб.индексиров.''): narrow-band emission--phosphors--photoluminescence--substitution strategy--white light-emitting diodes
Аннотация: Narrow-band luminescence materials used in white light-emitting diodes (WLEDs) have demonstrated a great potential to increase the maximum accessible color gamut, improve the color rendition, or enhance the visual luminous efficacy for illumination and display devices. So far, the discovery of narrow-band rare earth doped phosphors for emerging applications remains challenging owing to the limited systems in use and the broadening effect of 4f–5d transition. Here, two narrow-band cyan-emitting phosphors with the UCr4C4-related type structure, RbNa2K(Li3SiO4)4:Eu2+ (RNKLSO:Eu2+) and CsNa2K(Li3SiO4)4:Eu2+ (CNKLSO:Eu2+), are reported. The narrow-band emission results from the highly condensed network and a cube-like site for the activator (Eu2+). The emission peak assignments are investigated, and the variations of luminescence behavior with compositional changes of alkali cations are elaborated in detail. RNKLSO:8% Eu2+ (95%@250 °C of the integrated emission intensity at 25 °C) shows better thermal stability than that of CNKLSO:8% Eu2+ (79%@250 °C), which can be explained by the thermally activated crossover process represented in the configurational coordinate diagram. The optical properties of the as-fabricated WLEDs are studied and demonstrate potential with tunable properties for the full spectrum phosphor-converted LEDs. These findings in UCr4C4-type phases help shedding light on new avenues for fabricating new and totally unexpected narrow-emitting phosphors with versatile applications.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Qiao, Jianwei, Ning, Lixin, Molokeev M. S., Chuang, Yu-Chun, Liu, Quanlin, Xia, Zhiguo
Заглавие : Eu2+ site preferences in the mixed cation K2BaCa(PO4)2 and thermally stable luminescence
Место публикации : J. Am. Chem. Soc. - 2018. - Vol. 140, Is. 30. - P.9730-9736. - ISSN 0002-7863, DOI 10.1021/jacs.8b06021
Примечания : Cited References: 40. - This work is supported by the National Natural Science Foundation of China (No. 51722202, 91622125, 51572023, and 11574003), Natural Science Foundations of Beijing (2172036) and M.M. acknowledges support of the Russian Foundation for Basic Research (17-52-53031).
Предметные рубрики: LIGHT-EMITTING-DIODES
SOLID-SOLUTION
PHOSPHORS
GREEN
BLUE
Аннотация: Site preferences of dopant Eu2+ on the locations of K+, Ba2+, and Ca2+ in the mixed cation phosphate K2BaCa(PO4)2 (KBCP) are quantitatively analyzed via a combined experimental and theoretical method to develop a blue-emitting phosphor with thermally stable luminescence. Eu2+ ions are located at K2 (M2) and K3 (M3) sites of KBCP, with the latter occupation relatively more stable than the former, corresponding to emissions at 438 and 465 nm, respectively. KBCP:Eu2+ phosphor exhibits highly thermal stable luminescence even up to 200 °C, which is interpreted as due to a balance between thermal ionization and recombination of Eu2+ 5d excited-state centers with the involvement of electrons trapped at crystal defect levels. Our results can initiate more exploration of activator site engineering in phosphors and therefore allow predictive control of photoluminescence tuning and thermally stable luminescence for emerging applications in white LEDs.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Fang M. -H., Mahlik S., Lazarowska A., Grinberg M., Molokeev M. S., Sheu H. -S., Lee J. -F., Liu R. -S.
Заглавие : Structural Evolution and Effect of the Neighboring Cation on the Photoluminescence of Sr(LiAl3)1−x(SiMg3)xN4:Eu2+ Phosphors
Место публикации : Angew. Chem. Int. Ed. - 2019. - Vol. 58, Is. 23. - P.7767-7772. - ISSN 14337851 (ISSN), DOI 10.1002/anie.201903178
Примечания : Cited References: 23. - This work was supported by the Ministry of Science and Technology of Taiwan (Contract Nos. MOST 107‐2113‐M‐002‐008‐MY3 and MOST 107–2923‐M‐002‐004‐MY3). This work was supported by the National Science Centre Poland grant Opus no. 2016/23/B/ST3/03911 and the National Centre for Research and Development Poland Grant (No. PL‐TW/V/1/2018).
Предметные рубрики: Solid-Solution Phosphors
Аннотация: In this study, a series of Sr(LiAl3)1−x(SiMg3)xN4:Eu2+ (SLA‐SSM) phosphors were synthesized by a solid‐solution process. The emission peak maxima of SLA‐SSM range from 615 nm to 680 nm, which indicates structural differences in these materials. 7Li solid‐state NMR spectroscopy was utilized to distinguish between the Li(1)N4 and Li(2)N4 tetrahedra in SLA‐SSM. Differences in the coordination environments of the two Sr sites were found which explain the unexpected luminescent properties. Three discernible morphologies were detected by scanning electron microscopy. Temperature‐dependent photoluminescence and decay times were used to understand the diverse environments of europium ions in the two strontium sites Sr1 and Sr2, which also support the NMR analysis. Moreover, X‐ray absorption near‐edge structure studies reveal that the Eu2+ concentration in SLA‐SSM is much higher than that in in SrLiAl3N4:Eu2+ and SrSiMg3N4:Eu2+ phosphors. Finally, an overall mechanism was proposed to explain the how the change in photoluminescence is controlled by the size of the coordinated cation.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gavrichkov V. A., Polukeev S. I., Ovchinnikov S. G.
Заглавие : Cation spin and superexchange interaction in oxide materials below and above spin crossover under high pressure [Electronic resource]
Место публикации : ArXiv. - 2019. - Ст.1911.06482
Вид и объем ресурса: Electronic text data
Примечания : Cited References: 63. - We acknowledge the support of the Russian Science Foundation through Grant 18-12-00022.
Предметные рубрики: Materials Science
Strongly Correlated Electrons
Аннотация: We derived simple rules for the sign of superexchange interaction based on the multielectron calculations of the superexchange interaction in the transition metal oxides that are valid both below and above spin crossover under high pressure. The superexchange interaction between two cations in dn configurations is given by a sum of individual contributions related to the electron-hole virtual excitations to the different states of the dn+1 and dn−1 configurations. Using these rules, we have analyzed the sign of the superexchange interaction of a number of oxides with magnetic cations in electron configurations from d2 till d8: the iron, cobalt, chromium, nickel, copper and manganese oxides with increasing pressure. The most interesting result concerns the magnetic state of cobalt and nickel oxides CoO, Ni2O3 and also La2CoO4, LaNiO3 isostructural to well-known high-TC and colossal magnetoresistance materials. These oxides have a spin 12 at the high pressure. Change of the interaction from antiferromagnetic below spin crossover to ferromagnetic above spin crossover is predicted for oxide materials with cations in d5(FeBO3) and d7(CoO) configurations, while for materials with the other dn configurations spin crossover under high pressure does not change the sign of the superexchange interaction.
Смотреть статью,
Читать в сети ИФ
Найти похожие
6.

Вид документа : Статья из сборника (выпуск продолж. издания)
Шифр издания :
Автор(ы) : Aplesnin S. S., Udod L. V., Loginov Y. Y., Kretinin V. V., Masyugin A. N.
Заглавие : Influence of cation substitution on dielectric and electric properties of bismuth stannates Bi2Sn1.9Meo.1O7 (Me=Cr, Mn)
Коллективы : International Scientific Conference Reshetnev Readings 2017
Место публикации : IOP Conf. Ser.: Mater. Sci. Eng.: IOP, 2019. - Vol. 467: 21st International Scientific Conference Reshetnev Readings 2017 (8 November 2018 through 8 November 2018) Conference code: 144163, Is. 1. - , DOI 10.1088/1757-899X/467/1/012014
Примечания : Cited References: 9. - This study was supported by the Russian Foundation for Basic Research project N 17-32-50080, the state order № 3.5743.2017/6.7.
Аннотация: The article studies effect of nonstoichiometric substitution of the tin ions by chromium and manganese ions on the dielectric and electrical properties of bismuth pyrostannate. The research performs measurements of the current-voltage characteristics, capacitance and tangent of the dielectric loss angle in the temperature range from 300 to 800 K; it finds a qualitative difference in the temperature behavior of the permittivity of bismuth pyrostannate with chromium and manganese ions. A change in the type of conductivity from hopping to tunneling emission is established. The change in the activation energy as a function of the ion radius is found.
Смотреть статью,
Scopus,
Читать в сети ИФ
Найти похожие
7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Knyazev Yu. V., Shishkina N. N., Bayukov O. A., Kirik N. P., Solovyov L. A., Zhizhaev A. M., Rabchevsky E. V., Anshits A. G.
Заглавие : Cation Distribution in the Composite Materials of the CaFe2O4-α-Fe2O3 Series
Коллективы : Russian Foundation for Basic Research; Government of the Krasnoyarsk Krai; Krasnoyarsk Regional Science Foundation [18-42-243011]; UMNIK program
Место публикации : J. Struct. Chem. - 2019. - Vol. 60, Is. 5. - P.763-771. - ISSN 0022-4766, DOI 10.1134/S0022476619050081. - ISSN 1573-8779(eISSN)
Примечания : Cited References: 25. - The study was performed with the financial support of the Russian Foundation for Basic Research, the Government of the Krasnoyarsk Krai, the Krasnoyarsk Regional Science Foundation within the project No. 18-42-243011 "The effect of the composition and the defective structure of CaFe2O4 based "core-shell" composite materials on their electronic and catalytic properties" and the UMNIK program.
Предметные рубрики: PD/P-TYPE CAFE2O4
OXYGEN
CONDUCTIVITY
Аннотация: Structured composite materials CaFe2O4-α-Fe2O3 (α-Fe2O3 content is 2–82 wt.%) are obtained with the method of solid-phase synthesis at 1000 °C. The phase composition of the samples is studied using powder X-ray diffraction. It is shown that the content of CaFe2O4 and α-Fe2O3 phases changes linearly, depending on the composition of the starting material. The scanning electron microscopy data indicate the formation of a two-phase system α-Fe2O3-CaFe2O4. The Mössbauer spectroscopy data at room temperature testify the formation of cationic iron vacancies in the CaFe2O4 crystal structure in the absence of α-Fe2O3 structural defects. Cationic vacancies can be formed during the synthesis in the atmosphere of air.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vasiliev A. D., Golovnev N. N.
Заглавие : Structure of the oxonium compound of pefloxacinium hexachloridostannate(IV)
Коллективы : Ministry of Education of the Russian Federation [4.7666.2017/BCh]; Siberian Federal University [4.7666.2017/BCh]
Место публикации : J. Struct. Chem. - 2018. - Vol. 59, Is. 3. - P.641-645. - ISSN 0022-4766, DOI 10.1134/S0022476618030198. - ISSN 1573-8779(eISSN)
Примечания : Cited References: 13. - The work was performed within the State Contact of the Ministry of Education of the Russian Federation and the Siberian Federal University in 2017-2019 (4.7666.2017/BCh)
Предметные рубрики: ANTIBACTERIAL AGENTS
QUINOLONE
Ключевые слова (''Своб.индексиров.''): pefloxacinium cation--oxonium cation--chloride ion--hexachloridostannate(iv) anion--ionic compound--crystal structure
Аннотация: The structure of tris{hexachloridostannate(IV)}-hexachloride-tetrakis(pefloxacinium)-tetraoxonium undecahydrate (CCDC 1551760) 4PefH 3 2+ , 4H3O+, 3SnCl 6 2− , 6Cl−, 11H2O (I), (PefH is pefloxacin) is determined. The I crystals are triclinic: a = 13.5474(10) Å, b = 15.2859(11) Å, c = 15.6586(11) Å, α = 94.467(1)°, β = 105.477(1)°, γ = 111.560(1)°, V = 2849.9(4) Å3, space group Pī, Z = 1. The structure is stabilized by multiple intermolecular hydrogen bonds and π–π-interactions between the PefH32+ ions.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
9.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Belyaev B. A., Drokin N. A., Poluboyarov V. A.
Заглавие : Impedance spectroscopy study of the electrical properties of cation-substituted barium hexaaluminate ceramics
Место публикации : Phys. Solid State. - 2018. - Vol. 60, Is. 2. - P.274-280. - ISSN 1063-7834, DOI 10.1134/S1063783418020063. - ISSN 1090-6460(eISSN)
Примечания : Cited References:18
Предметные рубрики: DIELECTRIC-RELAXATION
LIQUID-CRYSTALS
SPECTRA
Аннотация: We report on the behavior of frequency and temperature dependences of the impedance of a measuring cell in the form of a parallel-plate capacitor filled with barium hexaaluminate ceramics with four aluminum cations replaced by iron (BaO · 2Fe2O3 · 4Al2O3). The measurements have been performed in the frequency range of 0.5–108 Hz at temperatures of 20-375°C. A technique for determining the electrical properties of the investigated ceramics is proposed, which is based on an equivalent electric circuit allowing the recorded impedance spectra to be approximated with sufficiently high accuracy. The established spectral features are indicative of the presence of two electric relaxation times different from each other by three orders of magnitude. This fact is explained by the difference between the charge transport processes in the bulk of crystallites and thin intercrystallite spacers, for which the charge activation energies have been determined.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
10.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Dudnikov V. A., Orlov Yu. S., Gavrilkin S. Yu., Kazak N. V., Platunov M. S., Solovyov L. A., Vereshchagin S. N., Velikanov D. A., Ovchinnikov S. G.
Заглавие : Effect of cation ordering on a-sites on the physical properties of substituted rare-earth cobaltite oxides GD1-XSRXCOO3-Δ
Коллективы : Moscow International Symposium on Magnetism, Московский государственный университет им. М.В. Ломоносова, Российский фонд фундаментальных исследований
Место публикации : Moscow International Symposium on Magnetism (MISM-2017): 1-7 July 2017 : book of abstracts. - 2017. - Ст.4PO-I-48. - P.878 (Шифр 29916280)
РИНЦ,
Материалы симпозиума,
Читать в сети ИФ
Найти похожие
 1-10    11-20   21-30   31-40   41-50   51-60      
 

Другие библиотеки

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