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Effective regulation of electronic structures and luminescence properties of LiGd_(9)(SiO_(4))6-x(GeO_(4))xO_(2):Dy^(3+)phosphors by tetrahedral substitution

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Journal of Rare Earths 2023年第5期41卷 673-681,I0002页

作者： Yuanyuan Zhang Lefu mei Haikun Liu sergey m.Aksenov Dina V.Deyneko Deliang Chen School of materials Sciences and Technology Dongguan University of TechnologyDongguan 523808China School of materials Science and Engineering Xi'an Jiaotong UniversityXi'an 710049China Beijing Key Laboratory of materials Utilization of Nonmetallic minerals and Solid Wastes National Laboratory of Mineral MaterialsSchool of Materials Sciences and TechnologyChina University of GeosciencesBeijing 100083China Department of Energy and Chemical Engineering Dongguan University of TechnologyDongguan 523808China Laboratory of Arctic mineralogy and material Sciences Kola Science CentreRussian Academy of Sciences14 Fersman StrApatity184209Russia Laboratory of Nature-Inspired Technologies and Environmental Safety of the Arctic Kola Science CentreRussian Academy of SciencesApatity18420 Russia Department of Chemistry Lomonosov Moscow State UniversityMoscow119991Russia School of materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

A series of Dy^(3+)-activated phosphors with the general formula LiGd_(9)(SiO_(4))6-x(GeO_(4))xO_(2):Dy^(3+)(0≤x≤3)characterized by an apatite-type structure were successfully synthesized via a simple solid-state technique involving a partial substitution of[SiO_(4)]^(4-)with[GeO_(4)]^(4-)*** effects of homovalent[GeO_(4)]^(4-)-[SiO_(4)]^(4-)substitution on the crystal structure,electronic structure,luminescence properties and thermal performance of LiGd_(9)(SiO_(4))6-x(GeO_(4))xO_(2):Dy^(3+)phosphors were studied in *** phases and microstructure were performed by using X-ray diffraction(XRD)Rietveld refinement method and scanning electron microscopy(SEm)*** substitution of smaller[SiO_(4)]^(4-)ions by larger[GeO_(4)]^(4-)ones makes their unit cell parameters increase gradually,and their band gaps *** photoluminescence spectra of LiGd_(9)(SiO_(4))6-x(GeO_(4))xO_(2):Dy^(3+)(0≤x≤3)exhibit obvious emission peaks located at 477,573 and 675 nm within a visible wavelength region,resulting in an excellent white ***,the I573nm/I477nm values of LiGd_(9)(SiO_(4))6-x(GeO_(4))xO_(2):Dy^(3+)(0≤x≤3)become larger with the partial substitution of[SiO_(4)]^(4-)by[GeO_(4)]^(4-),and their CIE chromaticity coordinates exhibit a yellow shift.

关键词： Apatite Structure substitution Electronic structure White emitting Rare earths

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Impact of drilling waste pollution on land cover in a high subarctic forest-tundra zone

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Pedosphere 2022年第3期32卷 414-425页

作者： Anatoly OPEKUNOV marina OPEKUNOVA Stepan KUKUSHKIN sergey LISENKOV Institute of Earth Sciences St.Petersburg State UniversitySt.Petersburg 199178(Russia)

Global climate changes can lead to the destruction of the permafrost zone and contribute to the active transfer of pollutants to natural *** can be especially pronounced in the areas of oil and gas production in the *** study aimed to define the landscape components(i.e.,groundwater,soil water,soil,and indicator plant species)of chemical pollution with metals,oil hydrocarbons,and polycyclic aromatic hydrocarbons,from the discharge of drill *** at two sites in the forest-tundra zone of Western Siberia(Russia)were carried out within two years of *** migration was found in peaty-gley heavy loamy soils and iron-illuvial clayey podburs,but lateral migration of different pollutants did not exceed 200 ***,radial migration was practically absent owing to the high buffering capacity of the soil organic horizon and the upward flow of matter in the seasonal melt *** main indicators of drilling waste pollution were high concentrations of Sr,Ba,petroleum hydrocarbons,and Cl^(-)*** the waste disposal sites,the concentration of Ba and Sr in the soil water were 1150 and 1410μg L^(-1),respectively;in groundwater,they reached 721 and 2360μg L^(-1),*** the soil,Ba and Sr accumulated in the peaty horizon(798 and 706 mg kg^(-1),respectively).The concentration of Cl^(-)ions in the soil water at the site of waste discharge was 1912 mg L^(-1),and at a distance of 200 m,it decreased to 77.4 mg L^(-1).The Cl^(-)concentration in the groundwater was lower,and at a distance of 200 m,it was 38.9 mg L^(-1).The highest concentration of petroleum hydrocarbons in the surface layer was found in the peaty-gley soils(up to 2400 mg kg^(-1)).In glandular-illuvial podburs,it was 420 mg kg^(-1).In horizons BH and BC,it was close to the background values(27 and 33 mg kg^(-1),respectively).Alkalinization of soils and water under the influence of drill cuttings led to the death of oligotrophic and acidophilic vegetation at a distanc

关键词： metal petroleum hydrocarbons plant indicator species pollutant migration in soil polycyclic aromatic hydrocarbon

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Partnership for eXtreme Xtallography (PX^(2))—A state-of-the-art experimental facility for extreme-conditions crystallography: A case study of pressure-induced phase transition in natural ilvaite

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matter and Radiation at Extremes 2022年第2期7卷 62-71页

作者： Jingui Xu Dongzhou Zhang sergey N.Tkachev Przemyslaw K.Dera School of Ocean and Earth Science and Technology Hawai’i Institute of Geophysics and PlanetologyUniversity of Hawai’i at ManoaHonoluluHawaii 96822USA Center for Advanced Radiation Sources University of ChicagoChicagoIllinois 60437USA

Single-crystal x-ray diffraction(SCXRD)is an important tool to study the crystal structure and phase transitions of crystalline materials at elevated *** Partnership for eXtreme Xtallography(PX^(2))program at the GSECARS 13-Bm-C beamline of the Advanced Photon Source aims to provide state-of-the-art experimental capabilities to determine the crystal structures of materials under extreme conditions using ***^(2) provides a focused x-ray beam(12318μm^(2))at a monochromatic energy of 28.6 ***-pressure SCXRD experiments are performed with a six-circle diffractometer and a Pilatus3 photon-counting detector,facilitated by a membrane system for remote pressure control and an online ruby fluorescence system for pressure *** efficient,high-quality crystal structure determination at PX^(2) is exemplified by a study of pressure-induced phase transitions in natural ilvaite[CaFe^(2+)_(2 )Fe^(3+)Si_(2)O_(7)O(OH),P2_(1)/a space group].Two phase transitions are observed at high *** SCXRD data confirm the already-known ilvaite-I(P2_(1)/a)→ilvaite-II(Pnam)transformation at 0.4(1)GPa,and,a further phase transition is found to occur at 22.8(2)GPa where ilvaite-II transforms into ilvaite-III(P2_(1)/a).The crystal structure of the ilvaite-III is solved and refined in the P2_(1)/a space *** addition to the ilvaite-I→ilvaite-II→ilvaite-III phase transitions,two minor structural modifications are observed as discontinuities in the evolution of the FeO6 polyhedral geometries with pressure,which are likely associated with magnetic transitions.

关键词： phase extreme transitions

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Updated Kimura-Takemoto classification of atrophic gastritis

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World Journal of Clinical Cases 2021年第13期9卷 3014-3023页

作者： sergey m Kotelevets sergey A Chekh sergey Z Chukov Department of Therapy Medical InstituteNorth Caucasus State Academy for Humanities and TechnologiesCherkessk 369000Russia Department of Software Development Institute of Applied Mathematics and Information TechnologyNorth Caucasus State Academy of Humanities and TechnologiesCherkessk 369000Russia Department of mathematics Institute of Applied Mathematics and Information TechnologyNorth Caucasus State Academy of Humanities and TechnologiesCherkessk 369000Russia Department of Pathological Anatomy Stavropol State Medical UniversityStavropol 355017Russia

BACKGROUND The Updated Sydney system for visual evaluation of gastric mucosal atrophy viaendoscopic observation is subject to sampling error and interobserver *** Kimura-Takemoto classification system was developed to overcome *** compare the morphological classification of atrophic gastritis between theKimura-Takemoto system and the Updated Sydney *** total of 169 patients with atrophic gastritis were selected according to diagnosisby the visual endoscopic Kimura-Takemoto method. Following the UpdatedKimura-Takemoto classification system, one antrum biopsy and five gastriccorpus biopsies were taken according to the visual stages of the Kimura-Takemoto system. The Updated Kimura-Takemoto classification system was thenapplied to each and showed 165 to have histological mucosal atrophy;theremaining 4 patients had no histological evidence of atrophy in any biopsy. The Updated Kimura-Takemoto classification was verified as a referencemorphological method and applied for the diagnosis of atrophic gastritis. Addingone more biopsy from the antrum to the six biopsies according to the Updated Kimura-Takemoto classification, constitutes the updated combined Kimura-Takemoto classification and Sydney *** sensitivity for degree of mucosal atrophy assessed by the Updated Sydneysystem was 25% for mild, 36% for moderate, and 42% for severe, when comparedwith the Updated Kimura-Takemoto classification of atrophic gastritis formorphological diagnosis. Four types of multifocal atrophic gastritis wereidentified: sequential uniform (type 1;in 28%), sequential non-uniform (type 2;in7%), diffuse uniform (type 3;in 23%), diffuse non-uniform (type 4;in 24%), and"alternating atrophic – non-atrophic" (type 5;in 18%). The pattern of the spread ofatrophy, sequentially from the antrum to the cardiac segment of the stomach,which was described by the Updated Kimura-Takemoto system, washistologically confirmed in 82% of cases ***

关键词： Updated Sydney system Kimura-Takemoto classification Prevention Gastric cancer Atrophic gastritis morphology

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Experimental study of shear properties of 3D woven composite using digital image correlation and acoustic emission

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Acta mechanica Sinica 2020年第2期36卷 448-459页

作者： E.m.Strungar A.S.Yankin E.m.Zubova A.V.babushkin A.N.Dushko Center of Experimental mechanics Perm National Research Polytechnic University614990 PermRussian Federation Engineering Center PJSC“UEC-Saturn” 152903 RybinskRussian Federation

This work is dedicated to the experimental study of the shear properties of three-dimensional reinforced composites taking into account their structural features,in Iosipescu *** strains have been determined using Vic-3D non-contact three-dimensional digital optical *** evolution of inhomogeneous strain fields on the surface of composite specimens of the structure under study has been *** variants of strain averaging in the specimen working area have been analyzed using Vic-3D ***-6 acoustic emission system has been used to assess the structural integrity of composite materials under loading.

关键词： Carbon-fiber composite 3D reinforced composite Digital image correlation Acoustic emission technique Iosipescu test

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Investigation into the operation of an autothermal two-section subbituminous coal fluidized bed gasifier

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International Journal of Coal Science & Technology 2023年第3期10卷 190-203页

作者： Nikolay Abaimov Alexander Ryzhkov Alexey Dubinin Lu Ding Vladimir Tuponogov sergey Alekseenko Ural Federal University EkaterinburgRussia 6200022 Institute of Clean Coal Technology East China University of Science and TechnologyShanghai 200237China Institute of Thermophysics Siberian BranchRussian Academy of SciencesNovosibirskRussia 630090

Using a newly developed experimental setup,the features and advantages of an autothermal single-casing atmospheric sub-bituminous coal fluidized bed air-blown gasifier,combining a combustion and gasification section,and mixing the dispersed phase(inert material,char)and heat exchange between them through an annular transfer device,have been *** increase the efficiency of the gasifier,an experimental-computational method was developed find the conditions for optimal operation,combining changing the annular flow's geometry and regulating the primary air for gasification.A simple and reliable multizone thermodynamic calculation model makes it possible to predict the composition of char and syngas in the gasification section with acceptable *** method confirmed that a two-section fluidized bed gasifier can provide efficient gasification of solid fuels and is suitable for use in small-scale cogeneration *** with a heating value of 3.6-4.5 mJ/m^(3)and CGE of 38.2%-42.3%was obtained in the experimental setup without optimizing the primary air flow *** optimization,the indicators increased to the heating value of syngas of 5.20-5.34 mJ/m^(3)and CGE of 42.5%-50.0%.With heat regeneration of 0.8,CGE increases to 70%.

关键词： Coal Syngas Gasification Bubbling fluidized bed Thermodynamics modeling

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Thermodynamics of Phase Equilibria in FeO-TiO2-Al_(2)O_(3)System

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China's Refractories 2022年第2期31卷 40-44页

作者： Oksana m.BORYSENKO sergey m.LOGVINKOV Galina m.SHABANOVA Andrii A.IVASHURA Alla m.KOROHODSKA Kharkiv Polytechnic Institute National Technical UniversityKharkiv 61002Ukraine

This scientific paper discusses the information on the structure of the three-component system FeO-TiO_(2)-Al_(2)O_(3),which is necessary for the creation of heat-resistant oxide *** structure of binary systems:FeO-Al_(2)O_(3),FeO-TiO_(2),and Al_(2)O_(3)-TiO_(2)is described,and the data on the FeO-TiO_(2)-Al_(2)O_(3)system are *** thermodynamic data of all compounds of the system are given,on the basis of which the change in the Gibbs free energy in the temperature range of 800-1900 K for twenty-one exchange reactions was *** has been established that the triangulation of the FeO-TiO_(2)-Al_(2)O_(3)system changes in five temperature ranges:up to 1408 K(TiO_(2)exists in the polymorphic modification-anatase),1408-1537 K(TiO_(2)exists in the polymorphic modification-rutile and pseudobrookite is stable),1537-1630 K(thialite is stable),1630-2076 K(rearrangement cannot occur)and above 2076 K(the presence of the stoichiometric compound Al_(4)TiO_(8)is allowed).Two-phase equilibria up to 1408 K are stable:Al_(2)O_(3)-FeTiO_(3),FeTiO_(3)-FeAl_(2)O_(4),and FeAl_(2)O_(4)-Fe_(2)TiO_(4);in the temperature range of 1408-1537 K:FeAl_(2)O_(4)-TiO_(2),FeAl_(2)O_(4)-FeTi_(2)O_(5),FeAl_(2)O_(4)-FeTiO_(3),and FeAl_(2)O_(4)-Fe_(2)TiO_(4);in the temperature range of 1537-1630 K:FeAl_(2)O_(4)-TiO_(2),FeAl_(2)O_(4)-FeTi_(2)O_(5),FeAl_(2)O_(4)-FeTiO_(3),FeAl_(2)O_(4)-Fe_(2)TiO_(4),and FeAl_(2)O_(4)-Al_(2)TiO_(5);in the temperature range of 1630-2076 K:FeTi_(2)O_(5)-Al_(2)TiO_(5),Al_(2)TiO_(5)-FeTiO_(3),FeTiO_(3)-Al_(2)O_(3),FeTiO_(3)-FeAl_(2)O_(4),and FeAl_(2)O_(4)-Fe_(2)TiO_(4);over 2076 K:FeTi_(2)O_(5)-Al_(2)TiO_(5),FeTi_(2)O_(5)-Al_(4)TiO_(8),Al_(4)TiO_(8)-FeTiO_(3),Al_(4)TiO_(8)-Fe_(2)TiO_(4),Al_(4)TiO_(8)-FeO,and Al_(4)TiO_(8)-FeAl_(2)O_(4).

关键词： phase equilibria change in Gibbs free energy triangulation hercynite ulvospinel ilmenite pseudobrookite thialite

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3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,*** and energy abilities as a component of solid composite propellants

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Defence Technology（防务技术） 2022年第7期18卷 1148-1155页

作者： Anatoly G.Korepin Natalia m.Glushakova David B.Lempert Anatoly I.Kazakov Gennady V.Shilov Denis V.Korchagin Vadim m.Volokhov Elena S.Amosova sergey m.Aldoshin Institute of Problems of Chemical Physics Ac.Semenov Avenue 1Chernogolovka142432Russian Federation

The work addresses to the study of the molecular and crystal structure and properties of a new energyintensive compound 3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine(NBTAT),first obtained by the authors in *** compound crystallizes in the monoclinic system,space group P2(1)/n,density at room temperature 1.939 g/cm^(3).The energies of crystal packing and pairwise intermolecular interactions in NBTAT and its unnitrated analogue BTAT were calculated,and their comparative analysis was carried *** enthalpy of formation of NBTAT molecules was calculated by quantum-chemical methods using Gaussian 09,and the enthalpy of formation of NBTAT in the solid phase(618 kJ/mol)was *** energy capabilities of NBTAT as an oxidizer of solid composite propellants are *** is shown that in metal-free compositions NBTAT is significantly superior to ammonium perchlorate(AP),dinitramide ammonium salt(ADN),HmX,BTAT at all stages of rocket systems,and is comparable to the superdense CL-20 yielding to the latter at the lower stages and slightly winning at the upper stages.

关键词： Nitrogen heterocycles Quantum chemistry Enthalpy of formation 3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine Crystal structure Energetic ability

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A novel technique for unilateral dissection of the penile neurovascular bundle to prevent loss of penile sensation during treatment of Peyronie's disease-Initial results of a pilot study

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Current Urology 2023年第4期17卷 299-302页

作者： Alexandr m.Pinkhasov matthew Beamer Daniel Shulman Rachel Yakubov Esther Pinkhasov sergey Kravchick Department of Urology SUNY Upstate Medical University HospitalSyracuseNY 13202USA

Background:Plaque incision/excision and grafting are surgical techniques used to treat patients with Peyronie's disease who are refractory to less invasive interventions,have severe penile curvature,or have an hourglass ***,the procedure carries the risk of penile sensory loss because of the need for dissection of the neurovascular bundle(NVB).The aim of this study was to assess the feasibility of a novel technique for unilateral NVB dissection and its ability to preserve penile sensitivity while maintaining adequate correction of the penile *** and methods:Charts of patients who underwent unilateral NVB dissection during Peyronie's plaque incision/excision and grafting were retrospectively *** patients received preprocedural intracavernosal injections of Trimix,and the curvature was measured to be>70 *** 3 cases,an incision and minimal excision of the plaque were performed at the point of maximum curvature on the concave side of the *** 3 cases,Tutoplast allografts(Coloplast US,minneapolis,mN)were used,whereas autografts were used in 2 other *** patients were examined at 1,3,and 6 months after the procedure when curvature and penile sensation were ***:Five patients underwent this *** mean age of patients was 55 years(45-70 years).All plaques were dorsally *** mean preoperative curvature was 78 degrees(75-90 degrees).At the 6-month follow-up,all patients hadmetic *** 1 patient continued with phosphodiesterase-5 inhibitors to improve potency at the 6-month *** patients reported normal penile glans *** patients experienced decreased sensation at the site of NVB dissection,but this was only detected when compared with the contralateral *** 2 patients reported a difference after 6 months,and only a minor area of involvement was ***:Unilateral NVB dissection is a feasi

关键词： Peyronie's disease Neurovascular bundle dissection

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Fluctuating fine-scale spatial genetic structure in the common shrews (Eulipotyphla, mammalia)

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Integrative Zoology 2023年第3期18卷 469-492页

作者： Nikolay A.SHCHIPANOV Artem V.ARTAmONOV sergey V.TITOV Svetlana V.PAVLOVA A.N.Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia Department of Zoology and Ecology Penza State UniversityPenzaRussia

The spatial genetic structure is a topical issue in the studies of various aspects of ecology and *** the multilocus autocorrelation method with hypervariable microsatellite genetic markers,we investigated aﬁne-scale pattern of genetic structure in 5 local populations of the common shrew Sorex araneus separated by distances of 300–1000 m(the moscow chromosomal race).Spatial genetic autocorrelation analysis based on 5 microsatellite loci(expected heterozygosity>0.79)with 90 alleles revealed a consistent pattern of signiﬁcant positive genetic *** testing the autocorrelation at multiple scales from 25 to 500 m,we found that positive spatial genetic structure is detectable in distance classes ofmber of captures).In contrast to nonresident animals,the residents demonstrated prominent genetic *** difference(FST)between the populations was signiﬁcant(0.016–0.051)and comparable with that between populations of different races analyzed previously(0.016–0.038).FST was not associated with geographic *** demographic patterns allowed us to propose a scheme of genetic-structure dynamics involving periodic appearance of more related local groups and renewal of allelic proﬁles fromаcommon pool where the alleles are *** scheme predictsﬂuctuating genetic structure and random similar differences among local populations.

关键词： demographic pattern geneﬂow microsatellite spatial autocorrelation

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