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Tailoring Photophysical Processes of Er^(3+)-Doped Gd_(3)Ga_(5)O_(12) Garnets for Enhanced Photoluminescence via Al^(3+)Ion Preference Substitution
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作者 Zhengjie Tian Haiyan Wang +6 位作者 Yunfeng Lou Qihang Deng Zhi Yang Xiyong Chen Bingsuo Zou Mingjian Yuan Ruosheng Zeng 《Carbon Energy》 2025年第7期107-117,共11页
Rare-earth ion-doped garnets with excellent luminescent properties show great potential for temperature sensing,displays,and nondestructive detection.However,their limited luminescent modes and low photoluminescence q... Rare-earth ion-doped garnets with excellent luminescent properties show great potential for temperature sensing,displays,and nondestructive detection.However,their limited luminescent modes and low photoluminescence quantum yields(PLQY)restrict further applications.In this study,we synthesized Al^(3+),Er^(3+)-co-doped Gd_(3)Ga_(5)O_(12) garnets with multimode luminescence via a high-temperature solid-state method.Notably,the preferential substitution of Al^(3+)ion at octahedral-coordinated GaI sites significantly enhanced the charge density and electron transition probability,achieving a PLQY enhancement of the downshifting luminescence from 35.1%to 68.5%.Al^(3+)ion also influences electron relaxation during up-conversion luminescence,resulting in a color shift from red to yellow to green.Additionally,Al^(3+)incorporation increased the photoelectric conversion efficiency of light-emitting diodes from 2.9%to 6.3%and improved temperature sensing sensitivity from 2.7%to 5.1%K⁻1.This work provides new insights into the photophysical mechanisms and underscores the key role of Al^(3+)ion in optimizing the optical properties of garnet-based materials. 展开更多
关键词 Al^(3+)ion doping GARNET NIR luminescence RARE-EARTH temperature sensing
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Synthesis and luminescence properties of novel Ce^3+-doped Yb3Al5-xGaxO12 garnets with very fast decay time 被引量:1
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作者 Ru Li Jie Yin +3 位作者 Fei Du Peng Zhang Shangke Pan Jianguo Pan 《Journal of Rare Earths》 SCIE EI CAS CSCD 2018年第8期806-810,共5页
A novel series of Ce^3+-doped Yb3 Al(5-x)GaxO(12)(x = 0, 1,2, 3,4, 5) powders of ytterbium aluminum gallium garnets were synthesized by high temperature solid-state reaction in a carbon reducing atmosphere. The... A novel series of Ce^3+-doped Yb3 Al(5-x)GaxO(12)(x = 0, 1,2, 3,4, 5) powders of ytterbium aluminum gallium garnets were synthesized by high temperature solid-state reaction in a carbon reducing atmosphere. The ytterbium aluminum garnets were characterized by X-ray powder diffraction, UV-Vis diffuse reflectance spectra, photoluminescence spectra and decay curves. Moreover, the substitution effect for the Al^3+ sites with Ga^3+ in 0.5 at%Ce:Yb3 Al(5-x)GaxO(12)(x = 0,1, 2, 3, 4, 5) garnets were discussed. With the increase of Ga^3+ ion concentration, the visible absorption peaks within 400-450 nm have blue shift phenomenon,while the absorption peaks in the range of 330-350 nm and the absorption band edge red shifts.Furthermore, the short decay times are very short with less than 10 ns due to the Yb^3+ + Ce^3+→ Yb^2+ + Ce^4+ electron transfer reaction. 展开更多
关键词 Ytterbium aluminum gallium garnets High temperature solid-state reaction Photoluminescence Decay time Rare earths
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Magnetic Properties of Y<sub>3-2x</sub>Ca<sub>2x</sub>Fe<sub>5-x</sub>V<sub>x</sub>O<sub>12</sub>Garnets
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作者 Imaddin A. Al-Omari Ralph Skomski David J. Sellmyer 《Advances in Materials Physics and Chemistry》 2012年第3期116-120,共5页
A comprehensive study of the magnetic properties of Y3-2xCa2xFe5-xVxO12 (0 ≤ x ≤ 1) has been performed. The garnet ferrites samples were prepared by the ceramic technique, and X-ray diffraction analysis indicates th... A comprehensive study of the magnetic properties of Y3-2xCa2xFe5-xVxO12 (0 ≤ x ≤ 1) has been performed. The garnet ferrites samples were prepared by the ceramic technique, and X-ray diffraction analysis indicates the formation of single cubic phase. Vibrating sample magnetometry (VSM) and a superconducting quantum-interference device (SQUID) were used to measure the magnetic properties, especially the magnetization and thermo-magnetic behavior. The magnetization curves exhibit the typical characteristics of ferrimagnetic materials at both 4.2 K and at room temperature. The samples have a low coercivities (between 20 and 40 Oe) and saturation magnetizations as high as 36 emu/g at 4.2 K. The saturation magnetization decreases with V and Ca contents, reaching about 8 emu/g at 4.2 K (x = 1). For all samples, the saturation magnetization decreases with increasing temperature, whereas the Curie temperature increases for small values of x, from 557 K for x = 0 to a maximum of 590 K for x = 0.2. For larger values of x, it decreases and reaches 525 K for x = 1.0. The basic experimental trends reflect the occupancy of the tetrahedral 24d sites by vanadium in combination with the predominant intersublattice exchange constant Jad, although the nonzero magnetization at x = 1.0 indicates that about 10% of the substituted V atoms goes onto the octahedral 16a sites. 展开更多
关键词 Yttrium Iron garnets CURIE Temperature Saturation Magnetization MAGNETIC Moment
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An Experimental Study of Partial Melting of Metafelsic Rocks:Constraints on the Feature of Anatectic Melts and the Origin of Garnets in Collisional Orogens 被引量:3
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作者 Xu Luo Qiong-Xia Xia +1 位作者 Yong-Fei Zheng Wan-Cai Li 《Journal of Earth Science》 SCIE CAS CSCD 2022年第3期753-769,共17页
Crustal anatexis in continental subduction zones has great bearing on chemical differentiation of the continental crust at convergent plate boundaries.This was experimentally investigated for ultrahigh-pressure(UHP)me... Crustal anatexis in continental subduction zones has great bearing on chemical differentiation of the continental crust at convergent plate boundaries.This was experimentally investigated for ultrahigh-pressure(UHP)metafelsic rocks at 0.5-3.0 GPa and 650-900℃.The results show that partial melting begins at about 750℃ when pressure drops from 3.0 to 2.0 GPa,corresponding to decompressional exhumation of the deeply subducted continental crust.As the pressure further decreases to 1.0 GPa,the partial melting degree reaches the maximum of~25%at 900℃.Partial melts produced in these experiments are rich in silica and alkali,and poor in iron,manganese and magnesium.As the degree of partial melting increases,the composition of partial melts gradually converges toward homogeneous one.In the absence of free water,the partial melting of metafelsic rocks were triggered by the breakdown of hydrous minerals.At low temperatures of~750℃at 1.0-2.0 GPa,phengite dehydration melting occurs at first,giving rise to small amounts of felsic melts and peritectic K-feldspar.As the temperature rises up to 850-900℃,biotite begins to break down and gives rise to large amounts of felsic melts and peritectic minerals such as garnet,K-feldspar and orthopyroxene.It is noted that peritectic garnet is much different from anatectic garnet crystallized from anatectic melts and metamorphic garnet formed through metamorphic dehydration reaction under subsolidus conditions.The peritectic garnet is characterized not only by anhedral shapes with many multiphase crystal inclusions but also by compositions poor in spessartine and grossular but rich in almandine and pyrope.On the other hand,the anatectic garnets are characterized not only by euhedral shapes with few inclusions but also by compositions rich in grossular and spessartine but poor in almandine and pyrope.These observations provide experimental constraints on the origin of garnets in UHP metamorphic rocks,which have great bearing on understanding of anatectic metamorphism in collisional orogens. 展开更多
关键词 collisional orogen partial melting experimental petrology metafelsic rocks GARNET MELTS
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The Discovery of Phlogopite Exsolution Lamellae in Garnets of Eclogite Inclusions, Liaoning Province 被引量:1
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作者 Zhou Xiuzhong Institute of Mineral Deposits, Chinese Academy of Geological Sciences, Beijing Liu Xinzhu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1997年第1期33-42,共10页
In No. 50 kimberlite pipe of Fuxian County, Liaoning Province, an eclogite inclusion(nodule), which is extremely rare in kimberlites, was discovered and phlogopite exsolutionlamellae were found in garnets of the inclu... In No. 50 kimberlite pipe of Fuxian County, Liaoning Province, an eclogite inclusion(nodule), which is extremely rare in kimberlites, was discovered and phlogopite exsolutionlamellae were found in garnets of the inclusion. Microscopic, TEM and energy spectral observa-tions and studies confirmed that these lamellae are phlogopite. They are colourless and acicularin section, generally 0.5-5μm in width and 10-100μm in length. Nevertheless, fine lamellae,0.05-0.1μm wide and 1-2μm long, are also well developed. Along [111] of the garnet, three setsof phlogopite lamellae show oriented arrangement approximately at angles of 60°-70°, indi-cating that these lamellae might be the product of exsolution from garnet as a result ofpressure-release when eclogite ascended from the relatively deep level to the relatively shallowlevel of the mantle. Tiny acicular exsolution minerals (or inclusions) are commonly found ingarnet and pyroxene in eclogite inclusions of kimberlites all over the world and it has been re-ported that the identified exsolution minerals include pyroxene and rutile. This is the first timethat phlogopite exsolution lamillae were found in eclogite inclusions in the world. 展开更多
关键词 ECLOGITE GARNET PHLOGOPITE exsolution lamellae Liaoning Province
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Microstructural Features of Garnets in Jadeite Quartzite from Dabie Mountains, China 被引量:1
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作者 Wu Xiuling Mou Tao Han Yujing Test Center, China University of Geosciences, Wuhan 430074, China Li Douxing Laboratory of Atomic Imaging of Solid, Institute of Metal Research, Academia Sinica, Shenyang 110015, China 《Journal of Earth Science》 SCIE CAS CSCD 2000年第3期158-161,共4页
Garnet is an important rock forming mineral of high pressure and ultrahigh pressure metamorphic rocks. Its popular isomorphism complicates its chemical composition and crystal structure. The selected area electron ... Garnet is an important rock forming mineral of high pressure and ultrahigh pressure metamorphic rocks. Its popular isomorphism complicates its chemical composition and crystal structure. The selected area electron diffraction (SAED) and the high resolution electron microscopy (HREM) are used in this work to study the microstructures and ultrastructures of garnets in the jadeite quartzite from Dabie Mountains, China. The microstructures of the garnet occur mainly as free dislocations, dislocation walls, stacking faults, dislocation networks and sub grain boundaries. The dislocation density is ρ=n ×10 8/cm 2 ( n =1.7—7.5) and the deformation mechanism is the dislocation glide and dynamic recovery. The superstructures of the garnet crystal revealed by HREM occur mainly as dislocations, faults, domain structures and lattice deformations, indicating the strong stress during the formation of the jadeite quartzite. 展开更多
关键词 jadeite quartzite GARNET MICROSTRUCTURE HREM.
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Synthesis and Ferrimagnetic Behaviour of Mn Doped Rare Earth Iron Garnets 被引量:1
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作者 GUO Li YUAN Lin +2 位作者 PENG Wen YUAN Hong-ming FENG Shou-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第3期391-394,共4页
Rare earth iron garnets R3Fe5-xMnxO12(R=Pr, Nd, Sm, Eu) were prepared through mild hydrothermal me- thod. The initial alkalinity of solutions was thought to play an important role in governing the content of Mn. The... Rare earth iron garnets R3Fe5-xMnxO12(R=Pr, Nd, Sm, Eu) were prepared through mild hydrothermal me- thod. The initial alkalinity of solutions was thought to play an important role in governing the content of Mn. The effect of substitution Fe^3+ ions by Mn^3+ ions on magnetic properties was investigated. The saturation magnetizations of Mn-doped samples are larger than that of corresponding parent compounds due to the moment of Mn^3+ ion being smaller than that of Fe^3+. It is clearly shown that incorporation of Mn^3+ gives rise to significant variations in the Curie temperature. With increasing of Mn content x, Curie temperatures reduced sharply for the garnets, which could be explained by the exchange interaction between a-d Fe^3+ being reduced in these compounds. 展开更多
关键词 Hydrothermal synthesis GARNET SUBSTITUTION FERRIMAGNETISM
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Magnetooptics of non-Kramers Eu^(3+) ions in garnets:analysis complemented by crystal-field splitting modeling calculations 被引量:1
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作者 Uygun V.Valiev John B.Gruber +3 位作者 Anvar K.Mukhammadiev Vasiliy O.Pelenovich 付德君 Gary W.Burdick 《Journal of Rare Earths》 SCIE EI CAS CSCD 2013年第9期837-842,共6页
Spectra of absorption, luminescence, magnetic circular dichroism (MCD), and magnetic circular polarization of lumines- cence (MCPL) in Gd3Ga5O12:Eu3+ and Eu3Ga3O12 garnets were studied within the visible spectra... Spectra of absorption, luminescence, magnetic circular dichroism (MCD), and magnetic circular polarization of lumines- cence (MCPL) in Gd3Ga5O12:Eu3+ and Eu3Ga3O12 garnets were studied within the visible spectral range at 300 K. Analysis of the spectral and temperature dependences of the magnetooptical and optical spectra made it possible to identify the magneto-dipole (MD) and electro-dipole (ED) 4f→4f transitions occurring between Stark sublevels of the 7FJ (J=1, 2) and 5D0 multiplets in Eua+-containing garnet structures. Quantum mechanical "mixing" had significant influence on quasi-degenerate states of the non-Kramers rare-earth Eu3+ ion for Eu3GasOl2 in MCD due to forbidden MD transition 7F1→SD0 and for GdaGasOiE:EU3+ in MCPL due to MD 4f→4f transition 5Do→7F1 and forced ED-transition 5Do→7F2. A parameterized Hamiltonian defined to operate within the entire 4f(6) ground electronic configuration of Eu3+ ion was used to model the experimental Stark levels, including their irreducible rep- resentations and wavefunctions. The crystal-field parameters were determined through a Monte-Carlo method in which nine in- dependent crystal-field parameters, Bkq, were given random starting values and optimized using standard least-squares fitting between calculated and experimental levels. The final fitting standard deviation between 57 calculated-to-experimental levels was 0.73 meV. 展开更多
关键词 magnetic circular dichroism magnetic circular polarization luminescence adsorption GARNET non-Kramers ion rare earths
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Hydrothermal Synthesis, Characterization and Magnetic Properties of Rare Earth Iron Garnets Sm_3Fe_5O_(12) and Eu_3Fe_5O_(12) 被引量:1
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作者 GUO Li YUAN Hong-ming HUANG Ke-ke YUAN Lin LIU Shao-kong FENG Shou-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第5期715-719,共5页
The rare earth iron garnets R3Fe5O12(R=Sm, Eu) were synthesized under mild hydrothermal conditions, and their crystal growth was found to be sensitive to alkalinity, reaction temperature and time. The as-prepared sa... The rare earth iron garnets R3Fe5O12(R=Sm, Eu) were synthesized under mild hydrothermal conditions, and their crystal growth was found to be sensitive to alkalinity, reaction temperature and time. The as-prepared samples were characterized by powder X-ray diffraction(XRD), scanning electron microscopy(SEM), infrared spectra(IR) and Raman spectrum. The M vs. H loops and magnetic parameters have been traced with a vibrating sample magnetometer(VSM) and superconducting quantum interference devices(SQUIDs) magnetometer. We proposed the formation mechanisms and formulated a reasonable explanation for their growth habits. Different morphologic characteristics were observed by changing alkalinity in the reaction systems. The magnetic studies gave saturation magnetization(Ms) and Curie temperature(TC). The magnetic behaviors of Sm3Fe5O12 and Eu3Fe5O12 in mild hydrothermal systems are comparable with those in high temperature solid state reactions. 展开更多
关键词 Rare earth iron garnet Hydrothermal synthesis Magnetism
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Tectonic evolution of the Karakoram metamorphic complex(NW Himalayas)reflected in the 3D structures of spiral garnets:Insights from X-ray computed micro-tomography
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作者 M.Sayab D.Aerden +1 位作者 J.Kuva W.U.Hassan 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第3期528-540,共13页
Spiral garnet porphyroblasts are known to record lengthy periods of deformation and metamorphism by preserving single or multiple FIAs(Foliation Intersection Axis)formed normal to tectonic shortening directions.Thanks... Spiral garnet porphyroblasts are known to record lengthy periods of deformation and metamorphism by preserving single or multiple FIAs(Foliation Intersection Axis)formed normal to tectonic shortening directions.Thanks to technological advances in X-ray computed micro-tomography(XCMT),FIAs can now be readily determined in relatively large samples in contrast to previous methods that require the preparation of a set of radial vertical and horizontal thin sections of samples.XCMT scanning not only alleviates tedious thin section based procedures but also illuminates the complete internal architecture of a rock sample allowing three-dimensional(3D)quantitative shape analysis of an individual porphyroblast as well as precise measurement of FIAs.We applied the technique to a sample from the Hunza Valley in the Karakoram metamorphic complex(KMC),NW Himalayas,containing numerous garnet porphyroblasts with spiral-shaped inclusion trails.The XCMT imaging reveals an E-W trending FIA within the sample,which is consistent with orthogonal N-S collision of the India-Kohistan Island Arc with Asia.Garnet long axes(X_(GT))have variable plunges that define a broad sub-vertical maximum and a small sub-horizontal maximum.The X_(GT) principle maxima lie at N-090 and N-120.Smaller maxima lie at N-020 and N-340.Geometric relationships between X_(GT) axes and FIA orientation in the sample suggest that porphyroblast shapes are controlled by the geometry of the lens-shaped microlithons in which they tend to nucleate and grow.The orientation of inclusion trails and matrix foliations in the sample are correlated with three discrete tectono-metamorphic events that respectively produced andalusite,sillimanite and kyanite in the KMC.Late staurolite growth in the sample reveals how the rocks extruded to the surface via a significant role of roll-on tectonics,which can be correlated with the Central Himalayas. 展开更多
关键词 PORPHYROBLAST Garnet FIA X-ray tomography KARAKORAM HIMALAYAS
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Chemical composition of oscillatory zoned garnets from the largescale Mengya'a Pb–Zn skarn deposit: implications for fluid physicochemical conditions and formation
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作者 Yan Zhang Cuihua Chen +4 位作者 Yulong Yang Xuhao Kang Ying Gu Xiang Lai Xiaojie Chen 《Acta Geochimica》 EI CAS CSCD 2022年第3期536-550,共15页
The Mengya’a Lead–zinc deposit is a large skarn deposit in the north of the eastern segment of Gangdese metallogenic belt.The garnet is the main altered mineral in the Mengya’a area.The color of the garnet varies f... The Mengya’a Lead–zinc deposit is a large skarn deposit in the north of the eastern segment of Gangdese metallogenic belt.The garnet is the main altered mineral in the Mengya’a area.The color of the garnet varies from chartreuse to dark yellow brown and to russet.The brown garnet(Grt1)is related to pyrrhotite and chalcopyrite,and the green garnet(Grt2)is associated with lead–zinc mineralization.LA-ICP-MS is the induced coupled plasma mass spectrometry.This paper has used this technique to investigate Grt1 and Grt2.Grt1 develops core–rim textures with strong oscillation zone occurring in rim,whereas Grt2lacks core–rim textures and featured by oscillation zone.LA–ICP–MS analysis shows that garnets of Mengya’a are rich in CaO(29.90–37.52%)and FeO(21.17–33.35%),but low in Al_(2)O_(3)(0.05–4.85%).The calculated end members belong to grandite(grossular–andradite)garnets andradite.The negative Al(IV)versus Fe^(3+),positive Al(IV)versus total Al stoichiometric number,the positive Al(IV)versus Fe^(3+),and the negative Al(IV)versus total REE,all indicate that the substitution of REEs in garnets is controlled by YAG.All Garnets are depleted in large lithophile elements(e.g.,Rb=0.00–4.01 ppm,Sr=0.03–8.56 ppm).The total REE in Grt1 core is high(ΣREE=233–625 ppm),with HREE enriched pattern(LREE/HREE=0.33–1.69)and weak negative Eu anomalies(δEu=0.21–0.47).In contrast,the total REEs in the Grt1 rim and Grt2 are low(ΣREE=12.4–354 ppm;ΣREE=21.0–65.3 ppm),with LREE enriched pattern(LREE/HREE=0.54–34.4;LREE/HREE=11.4–682)and positive Eu anomalies(δEu=0.35–27.2;δEu=1.02–30.7).After data compilation of garnet chemicals,we found that the early fluid responsible for the core of Grt1 was a relatively closed and chloride-depleted fluid system.It was close-to-neutral,with a low water–rock ratio.The core of garnet was formed by fluid diffusion in metasomatic processes.The fluid was changed into a relatively open system with reduced,chloride-rich,and weakacid fluid.It was fluid infiltration and metasomatism that resulted in the formation of Grt1 rim and Grt2. 展开更多
关键词 GARNET In-situ LA–ICP–MS analysis The Mengya’s Lead–Zinc skarn deposit TIBET
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Electromagneto-Optical Scanning of the Magnetic Domains Local Areas of Bismuth-Substituted Yttrium Iron Garnets
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作者 Vadim E. Koronovskyy Alehander A. Kalenichenko 《Journal of Modern Physics》 2011年第8期908-912,共5页
Magneto-electric properties of the magnetic domains local areas of bismuth-substituted yttrium iron garnet films are investigated. The electromagneto-optical (EMO) scanning method was used in our experiments when prob... Magneto-electric properties of the magnetic domains local areas of bismuth-substituted yttrium iron garnet films are investigated. The electromagneto-optical (EMO) scanning method was used in our experiments when probing by laser beam various sites of separate magnetic domains of the film. Registered in our experiments the nonlinear and linear components of EMO effect does not remain to constants at optical scanning of various points of the magnetic domain. I.e. the local EMOE picture from the separate sites of the domain must be more informative than an averaged one in the multidomain case. 展开更多
关键词 Magneto-Electric Electromagneto-Optical DOMAIN YTTRIUM IRON GARNET
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Fe-Mn interdiffusion in aluminosilicate garnets
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作者 Yanjun Yin Baohua Zhang Xinzhuan Guo 《Geoscience Frontiers》 SCIE CAS CSCD 2024年第1期118-125,共8页
Precise determination of cation diffusivity in garnet can provide critical information for quantitatively understanding the timescales and thermodynamics of various geological processes,but very few studies have been ... Precise determination of cation diffusivity in garnet can provide critical information for quantitatively understanding the timescales and thermodynamics of various geological processes,but very few studies have been performed for Fe-Mn interdiffusion.In this study,Fe-Mn interdiffusion rates in natural single crystals of Mn-bearing garnet with 750 ppm H2O are determined at 6 GPa and 1273-1573 K in a Kawai-type multi-anvil apparatus.Diffusion profiles were acquired by electron microprobe and fitted using Boltzmann-Matano equation.The experimental results show that the Fe-Mn interdiffusion coefficient(DFe-Mn)slightly decreases with increasing XFe.The experimentally determined DFe-Mn in Mn-bearing garnet can be fitted by the Arrhenius equation:DFe-Mn(m2/s)=D0XFenexp(-E*/RT),where E*=(1-XFe)E*Mn+XFeE*Fe,D0=8.06-6.04+9.87×10-9 m2/s,E*Mn=248±27 KJ/mol,E*Fe=226±59 KJ/mol,n=-1.36±0.51.The comparing the present results with previous experimental data suggest that water can greatly enhance the DFe-Mn in garnet.Our results indicate that the time required for homogenization of the compositional zoning of a garnet is much shorter than previously thought. 展开更多
关键词 Fe-Mn interdiffusion Diffusion coefficient GARNET High pressure experiment Water
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Petrology of Eclogite at Huwan,Western Dabie and Implications for Phase Equilibrium Modeling on LT-HP/UHP Eclogite
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作者 Bin Xia Ying Cui +1 位作者 Yunfeng Shang Jingtao Shi 《Journal of Earth Science》 2025年第3期1018-1032,共15页
Phase equilibrium modeling using internally consistent thermodynamic dataset and associated activity-composition(a-x)models are very helpful for quantifying P-T evolution for eclogite,which is the basis for decipherin... Phase equilibrium modeling using internally consistent thermodynamic dataset and associated activity-composition(a-x)models are very helpful for quantifying P-T evolution for eclogite,which is the basis for deciphering the geodynamic processes in subduction zones.In this study,we apply different versions of datasets(ds55 and ds62)and associated a-x relations to a wellestablished LT-HP eclogite at Huwan in the classic western Dabie orogen to constrain its P-T evolution.The eclogite comprises garnet+omphacite+amphibole+white mica+epidote+quartz+chlorite+rutile/ilmenite/sphene.Garnet porphyroblasts show mono-variation in the end members(spessartine from 17 mol%to 0,pyrope from 2 mol%to 18 mol%,almandine from 47 mol%to 64mol%and grossular from 35 mol%to 18 mol%)from core to rim.Phase diagrams combined with compositional isopleth thermobarometry show that dataset ds62 and associated a-x relations yield P_(max)of~33 kbar at~560℃,conflicting with our petrological observations and previous studies.On the other hand,phase equilibrium modeling using dataset ds62 and a revised symmetric garnet a-x model irrespective of Fe^(3+)(O)gives P_(max)of~27 kbar at~560℃,consistent with the results using dataset ds55 and associated a-x relations.Therefore,we recommend a symmetric model for garnet involving py,alm,gr and spss,without Fe~(3+)components,instead of the asymmetric garnet a-x relations involving py,alm,gr,spss and kho by White et al.(2014),for calculating phase diagrams for LT-(U)HP eclogite when using dataset ds62.In this study,the defined P-T path is characterized by a segment of the prograde evolution showing a first moderate slope,followed by gentle then steep slopes,representing the thermal structure evolution recorded by slab surface during continental subduction.Our work combined with previous studies conclude that in western Dabie,the Huwan HP eclogite belt to the north and the Hong'an HP eclogite belt to the south belong to the same HP slice overlying the Xinxian UHP slice. 展开更多
关键词 phase equilibrium modeling LT-HP eclogite continental subduction western Dabie garnets PETROLOGY
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Compositions of Jurassic detrital garnets in Hefei Basin and its implication to provenance reconstruction and stratigraphic correlation 被引量:2
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作者 李任伟 李忠 +3 位作者 江茂生 孙枢 金福全 张文华 《Science China Earth Sciences》 SCIE EI CAS 2000年第S1期167-177,共11页
The compositions of Jurassic detrital garnets in Hefei Basin are complicated. Contents of the end member are from zero to 43% for pyrope, from less than 1% to 50% for grossular, from 2% to 92% for almandine, and from ... The compositions of Jurassic detrital garnets in Hefei Basin are complicated. Contents of the end member are from zero to 43% for pyrope, from less than 1% to 50% for grossular, from 2% to 92% for almandine, and from zero to 88% for spessartine. Part of relatively pyrope-rich detrital garnets might be originated from high pressure-ultrahigh pressure metamorphic rocks. Contents of spessartine in garnets from the present metamorphic rocks of the Dabie Mountains, including the greenschists of Foziling Group, are lower than 30%. Therefore, they would not be the source of the spessartine-rich detrital garnets in the Jurassic sedimentary rocks of the Hefei Basin. Chemical compositions of the Jurassic detrital garnets in the Hefei Basin have some characteristics in the distribution with strata, which can be applied to study of the sedimentary filling sequence and stratigraphic correlation. 展开更多
关键词 DETRITAL garnets PROVENANCE JURASSIC DABIE Mountains Hefei Basin.
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Synthesis and Coloring Properties of A Novel Garnet-type Green Ceramic Pigment Y_(3)Ga_(3)MgSiO_(12)∶Cr^(3+)
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作者 YANG Sihan ZHANG Qian +4 位作者 ZHAO Chuxin LIU Danhe GONG Xinjiao CHEN Yufei WANG Xuejiao 《发光学报》 北大核心 2025年第4期704-712,共9页
Novel green ceramic pigments Y_(3)Ga_(3)MgSiO_(12)∶xCr^(3+)(x=0−0.2)were successfully synthesized via the conventional solid-state approach.The properties of the pigments were studied by XRD,FE-SEM,UV-Vis spectroscop... Novel green ceramic pigments Y_(3)Ga_(3)MgSiO_(12)∶xCr^(3+)(x=0−0.2)were successfully synthesized via the conventional solid-state approach.The properties of the pigments were studied by XRD,FE-SEM,UV-Vis spectroscopy,XPS,and chromaticity analysis.The findings reveal that the trivalent chromium ions occupy the[Ga1O6]octahedral sites within the garnet lattice,and the relatively weak crystal field environment provided by the matrix endows the pigments with green characteristics.The samples prepared by calcination at 1400℃exhibit the most excellent performance in terms of phase purity,morphology,and color properties.The chromaticity values for the representative sample Y_(3)Ga_(3)MgSiO_(12)∶0.05Cr^(3+)are L^(*)=81.16,a^(*)=−12.53,and b^(*)=12.71,and the color remains stable after the stability test.Moreover,when glazed with Y_(3)Ga_(3)MgSiO_(12)∶xCr^(3+)(x=0−0.2)pigments,the smooth glaze surfaces exhibit vivid and saturated green tones,demonstrating their remarkable coloring capabilities and promising potential as a practical pigment for medium-temperature applications.This research underscores the vast application prospects of Y_(3)Ga_(3)MgSiO_(12)∶Cr^(3+)as an innovative green ceramic pigment. 展开更多
关键词 GARNET green pigments Cr^(3+)doping
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Gd_(3)Ga_(5)O_(12):A wide bandgap semiconductor electrolyte for ceramic fuel cells,effective at temperatures below 500℃
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作者 Junjiao Li Muhammad Yousaf +10 位作者 Jahangeer Ahmed Bushra Bibi Asma Noor Norah Alhokbany Muhammad Sajid Atif Nazar M.A.K.Yousaf Shah Xiaofeng Guo Xiangqin Ding Naveed Mushtaq Yuzheng Lu 《Journal of Rare Earths》 2025年第10期2248-2256,I0007,共10页
Searching for compatible electrolytes with Ni_(0.8)C_(00.15)Al_(0.05)LiO_(2-δ)(NCAL)electrodes that exhibit high ionic conductivity at low operational temperatures(<550℃)is crucial for advancing ceramics fuel cel... Searching for compatible electrolytes with Ni_(0.8)C_(00.15)Al_(0.05)LiO_(2-δ)(NCAL)electrodes that exhibit high ionic conductivity at low operational temperatures(<550℃)is crucial for advancing ceramics fuel cells(CFCs)research.In this work,the experimental and theoretical analyses demonstrate that the highly stable single-phase Gd_(3)Ga_(5)O_(12)(GGO)garnet structure,composed of Gd-O octahedrons and Ga-O tetrahedrons,provides more active sites for ion transport,resulting in enhanced peak power density(PPD)and stable open circuit voltage(OCV)at low operational temperatures.The unique internal garnet structure effectively reduces the interfacial impedance of the prepared fuel cell device,provides more active sites at triple-phase boundarie region,and increases the electrochemical stability.As a result,the constructed fuel cell device can deliver a superior peak power density of 770 mW/cm^(2)at 490℃.In addition,X-ray photoelectron spectroscopy,electrochemical impedance spectroscopy,and theoretical calculations further demonstrate electrolyte effectiveness of GGO,enabling stable an OCV even at a low temperature of 370℃under a H_(2)/air environment.This work contributes to a deeper understanding of the underlying mechanisms of a single-layer fuel cell device,which is essential for advancing this promising energy technology,even at a very low temperature of 370℃. 展开更多
关键词 Garnet structure Wide bandgap Solid oxide fuel cells Low temperature Oxygen ions transport Rare earths
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In-situ construction of nano-multifunctional interlayer to obtain intimate Li/garnet interface for dendrite-free all solid-state battery
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作者 Shiyu Yu Zhinan Gong +8 位作者 Min Gao Jie Li Wenfei Xie Yaqing Wei De Li Liang Yang Daming Chen Yuanxun Li Yong Chen 《Journal of Materials Science & Technology》 2025年第3期248-256,共9页
Garnet-based all-solid-state lithium batteries(ASSLBs)were considered as the most promising energy storage device due to their high energy density and good safety.However,interface problems caused by impurities such a... Garnet-based all-solid-state lithium batteries(ASSLBs)were considered as the most promising energy storage device due to their high energy density and good safety.However,interface problems caused by impurities such as Li_(2)CO_(3) on the surface still hinder the practical application of garnet-based ASSLBs.Here,we use a simple ultrasonic spraying method to coat SiO_(2) on the Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)surface,and in-situ construct Li_(4)SiO_(4)/Li_(2) O/Li_(2)1 Si5 nano-multifunctional interlayer through the high-temperature conversion reaction of SiO_(2).Experiments and density functional theory(DFT)calculations demonstrate that the introduced Li_(4)SiO_(4)/Li_(2) O/Li_(2)1 Si_(5) nano-multifunctional interlayer at the LLZTO/Li interface can significantly improve the air stability and interface contact of LLZTO/Li.As a result,the interface impedance of Li/SiO_(2)@LLZTO/Li was reduced to 24.2Ωcm^(-2),and it can operate stably over 2400 and 1000 h at current densities of 0.05 and 0.2 mA cm^(−2),respectively.The full cell assembled with LiFePO_(4)(LFP)as cathode(Li/SiO_(2)@LLZTO/LFP)also exhibits excellent cycling performance(capacity retention rate of 95%after 50 cycles at 0.1 C)and rate performance(140 mAh g^(−1) at 0.1 C and 107 mAh g−1 at 1 C).This research provides a strategy to improve interface problems and achieve dendrite-free ASSLBs through in-situ transformation constructed nano-multifunctional interlayers. 展开更多
关键词 Garnet electrolyte In-situ construction Ultrasonic spraying Nano-multifunctional interlayer All solid-state lithium batteries(ASSLBs)
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Geological, structural, and temporal framework of hematite-rich IOCG mineralization at La Farola deposit in the Candelaria-Punta del Cobre district, Chile
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作者 N.M.Seymour I.del Real +3 位作者 A.Canales H.Stein G.Yang J.Camacho 《Geoscience Frontiers》 2025年第5期225-243,共19页
Iron oxide-copper–gold(IOCG)deposits encompass a diverse set of mineralization styles,leading to outstanding questions about how different alteration facies are related across a single ore-producing system and the ov... Iron oxide-copper–gold(IOCG)deposits encompass a diverse set of mineralization styles,leading to outstanding questions about how different alteration facies are related across a single ore-producing system and the overarching mechanisms of ore genesis.This study investigates the age and characteristics of mineralization at the La Farola deposit,a hematite-dominated IOCG deposit located at the southern margin of the Candelaria-Punta del Cobre IOCG district of northern Chile.Two lithologically-controlled ore bodies occur along the WSW-ENE striking,∼18°NNW-dipping contact between the Lower Cretaceous Chañarcillo Group and Punta del Cobre Formation.Syn-mineralization N-S to NNW-SSE striking sinistral strike-slip faults likely acted as fluid pathways.Distinct mineral assemblages include an early Na-Ca assemblage(albite-scapolite)overprinted by skarnoid garnet with minor pyroxene,Ca-Fe(magnetite-actinolite),and K-Fe(magnetite-k-feldspar-biotite and minor sulfides)assemblages.The main sulfide mineralization(chalcopyrite-pyrite with minor bornite)is associated with specular hematite-white mica-K-feldspar-calcite and overprints all previous assemblages.The presence of hematite as the dominant Fe-oxide phase associated with Cu mineralization is characteristic of lower-temperature IOCG deposits,and may be a result of La Farola’s stratigraphic position<700 m higher than other deposits in the district.New U-Pb ages of 115.7±1.2 Ma for garnet and Re-Os ages of∼113–114 Ma for sulfides indicate mineralization occurred within a 3-million-year timeframe.These findings confirm hematite-dominant mineralization at La Farola was coeval with IOCG mineralization across the district.This research contributes to understanding IOCG systems and their formation mechanisms,highlighting the control local geological structures and alteration processes has on the diversity of mineralization types associated with a single IOCG system. 展开更多
关键词 Iron oxide-copper-gold deposits IOCG Hematite-dominant IOCG mineralization U-Pb dating in garnet Re-Osdating in sulfides
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Guiding and magneto–optical properties of TGG waveguide by proton implantation combined with femtosecond laser ablation
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作者 Chun-Xiao Liu Zi-Hao Wang +6 位作者 Bei-Er Guo Rui Yuan Yi-Fan Wang Yu-Hang Zhou Jia-Bin Sun Liao-Lin Zhang Hai-Tao Guo 《Chinese Physics B》 2025年第5期437-442,共6页
Integrating the magneto-optical effect into a waveguide-based photonic device becomes more and more interesting.In the work,the planar optical waveguide firstly was prepared in a terbium gallium garnet crystal(TGG)via... Integrating the magneto-optical effect into a waveguide-based photonic device becomes more and more interesting.In the work,the planar optical waveguide firstly was prepared in a terbium gallium garnet crystal(TGG)via the proton implantation with the energy of 4×10^(-1)MeV and the fluence of 6×10^(8)ions/μm^(2).Subsequently,a femtosecond laser with a central wavelength of 800 nm and a power of 3 mW was used to ablate the surface of the planar waveguide,forming the ridge optical waveguide.The dark-mode curve of the planar waveguide was measured by a prism coupling technique.The top-view morphology of the ridge waveguide was observed via a Nikon microscope.The mode field distributions of the planar and ridge waveguides were obtained by an end-face coupling system,and the propagation losses of the two waveguides were measured to be 2.26 dB/cm and 2.58 dB/cm,respectively.The Verdet constants were measured to be-72.7°/T·cm for the TGG substrate and-60.7°/T·cm for the ridge waveguide.The TGG waveguides have a potential in the fabrication of magneto-optical waveguide devices. 展开更多
关键词 optical waveguide ion implantation terbium gallium garnet crystal(TGG) magneto-optical effect femtosecond laser ablation
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