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Mossbauer,optical and structural properties of fe^(3+) ion in borate glass

Journal of Rare Earths 2025年第1期43卷 162-170,I0006页

作者： Essam A.Elkelany hesham Y.Amin A.samir M.M.El-hady h.h.El-Bahnasawy Moukhtar A.hassan Basic science Department Faculty of EngineeringSinai UniversityAl-Arish45511Egypt school of Information and Electrical Engineering Hangzhou City UniversityHangzhou30015China state Key laboratory of Modern Optical Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou310027China Basic science Department Faculty of Engineering at ShoubraBenha University11629Egypt Physics Department Faculty of ScienceAl-Azhar University11884CairoEgypt

lanthanum-bearing iron lithium borate glass is a quaternary system for oxide glasses and was prepared via the melt-quenching *** present article correlates the structure,optical,ligand field and M?ssbauer data on iron lithium borate glass co ntaining la^(3+).The density was measured,while the molar volume was *** physical parameters are *** increasing the la_(2)O_(3) content within the glass network,infrared spectra analysis reveals structural modifications such as the increase in BO_(4) units and the decline in both BO_(3) units and NBO bonds ***,optical absorption spectra were *** absorption spectra disclose a plethora of electronic transitions that are related to fe^(3+)in tetrahedral and octahedral sites,however,fe^(2+)phase is not observed in optical spectra,but it has a clear signature in M?ssbauer ***,the glass absorption edges undergo a clear blue shift,reflecting an increased band gap energy(1.96-2.28 eV).The decline in NBO bonds justifies this ***,the values of crystal field splitting are increased,while the values of Racah parameters are *** trend is justified by the decline in NBO bonds and increases electron localization around fe cations.M?ssbauer spectra confirm the existence of fe^(3+)in tetrahedral and octahedral sites,while fe^(2+)exists in only a tetrahedral *** increasing la_(2)O_(3) content,the isomer shift of fe^(3+)in tetrahedral sites changes to be 0.312-0.329 mm/s,while the isomer shift of octahedral fe^(3+)is 0.424-0.456 mm/*** findings coincide with optical *** the isomer shift of tetrahedral fe^(2+)is 0.902-0.911 mm/*** results of structural,optical and ligand field associated with M?ssbauer spectra open more vistas toward the utility of these samples in the optics realm.

关键词： fe3+ions Rare-earth oxide Mossbauer spectra ligand field parameters Optical properties

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green ionic metal-organic frameworks as nanocatalysts for CO_(2)fixation

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Nano Research 2025年第1期18卷 260-269页

作者： Nuria Martín Miguel Maireles-Porcar Julián sánchez Velandia Belén Altava francisco g.Cirujano Eduardo garcía-Verdugo Departamento de Química Inorgánica y Orgánica Universidad Jaume IAv.Sos Baynats/nCastellóde la PlanaCastellón 12071Spain

Co,Ni,and Zn iso-reticular coordination polymers of 2,5-dihydroxyterphthalic acid(h_(2)dot)can be rapidly obtained under room temperature and aqueous conditions using either sodium or ammonium hydroxide as the bases to deprotonate the *** use of metal bromides and tetrabutylammonium hydroxide(TBAOh)as the base allows the green synthesis of ionic metal-organic frameworks(MOfs),characterized by X-ray diffraction(XRD),fourier transform infrared(fTIR),scanning electron microscopy(sEM),thermo gravimetric analysis(TgA),h-nuclear magnetic resonance(NMR),elemental analysis,and X-ray photoelectron spectroscopy(XPs),and employed in the pressure,solvent,and additive-free CO_(2)fixation to epoxides by its cycloaddition to epichlorohydrin,exhibiting a cooperative behavior between the MOf and the ionic liquid formed within the framework,achieving TONs of the confined tetrabutylammonium bromide(TBABr)up to 700.

关键词： metal-organic frameworks(MOfs) ionic liquids heterogeneous catalysis CO_(2)conversion

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Erbium photoluminescence response related to nanoscale heterogeneities in sol-gel silicates

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Journal of Rare Earths 2013年第1期31卷 18-26页

作者： h.C.Vasconcelos M.g.Meirelles f.Rivera-lópez Department of Technological sciences and Development Azores University CEfITEC-Centre of Physics and Technological Research Physics Department of FCT/UNL Department of fundamental and Experimental Physics Electronics and SystemsUniversity of La Laguna

sol-gel glassy films of the siO2-TiO2-PO2.5-ErO2.5 system containing nanocrystallites of ErPO4, were obtained through suitable heat treatments. Variations in the shape and intensity of the Er3＋ photoluminescent signal around 1500 nm were linked to the nature of the host environment of the active ions; the specific features of the photoluminescent emission spectrum of the erbium 4113/2 metastable level were interpreted in terms of structural changes in the glassy films. The photoluminescent spectrum was found to be sensitive to the order （crystalline） or disorder （amorphous） of the Er3＋ ions neighbour within the glassy matrix. An amorphous envi- ronment led to a broadening of Er3＋ Pl emission band while a crystalline one was responsible for a drastic photoluminescent band- width narrowing. The presence of nanoscale heterogeneities caused a drastic photoluminescence intensity decrease. Changes in the shape of the decay curve of fluorescence lifetime were found also structurally dependent on volumetric defects, occurrence of phase separation and Er3＋-Er3＋ clustering effects as well.

关键词： sol-gel Er3+ optical probe nanoscale heterogeneities photoluminescence ErPO4 rare earths

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Elastic, thermodynamic, electronic, and optical properties of recently discovered superconducting transition metal boride NbRuB:An ab-initio investigation

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Chinese Physics B 2017年第10期26卷 339-347页

作者： f Parvin s h Naqib Department of Physics University of Rajshahi

The elastic, thermodynamic, electronic, and optical properties of recently discovered and potentially technologically important transition metal boride NbRuB, are investigated using the density functional formalism. Both generalized gradient approximation （ggA） and local density approximation （lDA） are used for optimizing the geometry and for estimating various elastic moduli and constants. The optical properties of NbRuB are studied for the first time with different photon polarizations. The frequency （energy） dependence of various optical constants complement quite well the essential features of the electronic band structure calculations. Debye temperature of NbRuB is estimated from the thermodynamical study. All these theoretical estimates are compared with published results, where available, and discussed in detail. Both electronic band structure and optical conductivity reveal robust metallic characteristics. The NbRuB possesses significant elastic anisotropy. Electronic features, on the other hand, are almost isotropic in nature. The effects of electronic band structure and Debye temperature on the emergence of superconductivity are also analyzed.

关键词： hard materials ternary borides DfT calculations electronic band structure optical properties superconductivity

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Attritor-milling of poly(amide imide) suspensions

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Particuology 2014年第6期12卷 92-96页

作者： M.f.h.Wolff s.Antonyuk s.heinrich g.A.schneider hamburg University of Technology Institute of Solids Process Engineering and Particle Technology hamburg University of Technology Institute of Advanced Ceramics

The milling behavior of poly(amide imide),which serves as a prototypical hydrophilic high-performance polymer with a high glass transition temperature,was *** milling conditions(milling times up to 7h,stirrer tip speeds of 3.4-4.9 m/s,and mass concentrations of 5-20%) were tested,and particle sizes as low as d50,33μm were *** milling was performed at 11℃ in an *** scanning calorimetry and thermogravimetric analysis were performed before and after milling to investigate the effect of milling on the glass transition temperature and on the decomposition behavior of the *** suspension obtained after milling was observed to be stable without the addition of stabilizers or the adjustment of the ph value,and no negative effect of milling on the polymer properties was *** attritor technique proved to be an adequate and efficient milling tool for the production of micrometer-sized high-performance polymer suspensions.

关键词： Attritor Polymer grinding suspension

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Cardiovascular Diabetology|空间多组学图谱揭示糖尿病大血管病变中的平滑肌表型转化与代谢重编程

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中国临床药理学与治疗学 2025年第2期 237页

作者： Qian Y Xiong s li l sun Z Zhang l Yuan W Cai h feng g Wang X Yao h gao Y guo l Wang Z 王中群江苏大学附属医院心内科

大血管病变是糖尿病影响人类健康的重要杀手，平滑肌细胞（sMCs）表型转化是糖尿病大血管病变的关键机制。随着空间多组学和单细胞技术的发展，基于组织切片的二维空间结构可实现纳米级基因表达检测，深入揭示疾病的病理学与病理生理学...

大血管病变是糖尿病影响人类健康的重要杀手，平滑肌细胞（sMCs）表型转化是糖尿病大血管病变的关键机制。随着空间多组学和单细胞技术的发展，基于组织切片的二维空间结构可实现纳米级基因表达检测，深入揭示疾病的病理学与病理生理学机制。有鉴于此，江苏大学附属医院王中群教授团队对糖尿病患者的下肢血管进行了空间转录组、空间代谢组和单细胞测序的系列研究。

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Characterization and source apportionment of volatile organic compounds in hong Kong:A 5-year study for three different archetypical sites

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Journal of Environmental sciences 2025年第5期151卷 424-440页

作者： Yuchen Mai Vincent Cheung Peter K.K.louie Kenneth leung Jimmy C.h.fung Alexis K.h.lau Donald R.B.lake Dasa gu Division of Environment and sustainability The Hong Kong University of Science and TechnologyHong Kong 999077China Environmental Protection Department Hong Kong 999077China Environment and Ecology Bureau Hong Kong 999077China Department of Chemistry University of CaliforniaIrvine 92617USA

Initial success has been achieved in hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three *** organic compounds(VOCs)are important for mitigating ozone pollution as its major *** study analyzed VOC characteristics of roadside,suburban,and rural sites in hong Kong to investigate their compositions,concentrations,and source *** showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,*** using Positive Matrix factorization(PMf)model,six sources were identified at the roadside site over five years:liquefied petroleum gas(lPg)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).similarly,six sources were distinguished at the suburban site,including lPg usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and lPg usage were the primary contributors to OfP and Oh reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OfP and Oh reactivity at the suburban and rural sites,*** findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas.

关键词： Volatile organic compounds Positive matrix factorization source apportionment Ozone formation

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3D tomographic analysis of equatorial plasma bubble using gNss-TEC data from Indonesian gNss Network

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Earth and Planetary Physics 2025年第1期9卷 127-136页

作者： Ihsan Naufal Muafiry Prayitno Abadi Teguh N.Pratama Dyah R.Martiningrum sri Ekawati Yuandhika gWismaya febrylian fChabibi gatot hPramono Research Center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian geospatial Information Agency(BIg) JakartaIndonesia Dept.of Physics Faculty of ScienceUniversiti Teknologi MalaysiaJohor BahruMalaysia Dept.Earth Planet sci. Hokkaido UniversitySapporoJapan school of Electrical Engineering Telkom UniversityBandungIndonesia

Equatorial Plasma Bubbles(EPBs)are ionospheric irregularities that take place near the magnetic *** most commonly occur after sunset during the equinox months,although they can also be observed during other *** phenomenon significantly disrupts radio wave signals essential to communication and navigation *** national network of global Navigation satellite system(gNss)receivers in Indonesia(>30°longitudinal range)provides an opportunity for detailed EPB *** explore this,we conducted preliminary 3D tomography of total electron content(TEC)data captured by gNss receivers following a geomagnetic storm on December 3,2023,when at least four EPB clusters occurred in the southeast Asian *** and extracted TEC depletion with a 120-minute running average were then used as inputs for a 3D tomography *** 2D spatial distribution consistently captured the four EPB clusters over *** tomography results were validated through a classical checkerboard test and comparisons with other ionospheric data sources,such as the global Ionospheric Map(gIM)and International Reference Ionosphere(IRI)*** of the results demonstrates the capability of the Indonesian gNss network to measure peak ionospheric *** findings highlight the potential for future three-dimensional research of plasma bubbles in low-latitude regions using existing gNss networks,with extensive longitudinal coverage.

关键词： EPB Indonesian gNss Network 3D tomography

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东北婆罗洲古地理重建:巴利奥宗(Baliojong)大洋板块地层碎屑物源和年代学

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地质学报 2025年第2期99卷 382-398页

作者：许迪 suzanna h A van de lAgEMAAT Junaidi AsIs 曹立成 Eldert l ADVOKAAT 姚会强中国地质大学(武汉)海洋学院乌特勒支大学地球科学系沙巴大学自然与科学学院广州海洋地质调查局国土资源部海底矿产资源重点实验室

受古大洋持续俯冲活动的影响,东南亚现存微陆块众多,其成因和构造演化复杂,使得该地区古地理重建难度极大,特别是东北婆罗洲地块的构造属性和前新生代古地理尚有较大争议。东北婆罗洲出露的巴利奥宗(Baliojong)大洋板块地层,是记录古大... 详细信息

受古大洋持续俯冲活动的影响,东南亚现存微陆块众多,其成因和构造演化复杂,使得该地区古地理重建难度极大,特别是东北婆罗洲地块的构造属性和前新生代古地理尚有较大争议。东北婆罗洲出露的巴利奥宗(Baliojong)大洋板块地层,是记录古大洋由洋壳扩张至俯冲消亡的珍贵素材。本文对该地层西段两个浊积岩剖面开展了详细的物源和年代学调查,综合运用全岩地球化学、矿物学、锆石U-Pb年代学-地球化学-形态学来限定其沉积时代和组成成分,进而揭示古大洋俯冲历史和上覆板块古地理。结果显示两剖面样品的各物源和年代学指标均存在较大差异,东侧浊积岩(剖面Bf2)较西侧浊积岩(剖面Bf5)具有更年轻的沉积年龄、更高的成分成熟度和碎屑组分含量、偏基性的母岩成分、更丰富和更大粒径的加里东期和印支期锆石颗粒。这些信息明确指示两套浊积岩为不同期次的俯冲增生产物。综合新获得碎屑年代学最大沉积年龄指标以及前人测定的硅质岩和玄武岩年龄,推测两套浊积岩形成于晚白垩世(～87 Ma和～93 Ma)。通过对比巴利奥宗浊积岩与婆罗洲及周缘板块物源区的锆石U-Pb年龄信号,发现其与印支地块南缘—东马地块—西北婆罗洲一带存在潜在的源汇联系,推测巴利奥宗大洋板块地层形成的俯冲带位置更靠近巽他大陆,而不是华南大陆。本研究揭示的东北婆罗洲晚白垩世古地理对重建南海—东南亚地区中生代古大洋俯冲体系具有重要意义。

关键词：古太平洋东北婆罗洲古地理晚白垩世锆石U-Pb年代学沉积年龄大洋板块地层

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Does mesenchymal stem cell’s secretome affect spinal sensory circuits?Implication for pain therapies

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Neural Regeneration Research 2025年第1期20卷 181-183页

作者： francesco ferrini Esri h.Juárez Adalberto Merighi Department of Veterinary sciences University of TurinGrugliascoTOItaly Department of Psychiatry and Neuroscience UniversitéLavalQuébec CityQCCanada

Mesenchymal stem cells(MsCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical *** have gained significant attention in regenerative medicine due to their ability to modulate the immune system and favor tissue *** enrich the medium in which they are cultivated with a broad range of bioactive molecules,including growth factors,cytokines,chemokines,enzymes,nucleic acids,and extracellular vesicles that collectively compose the MsC *** increasing number of pre-clinical studies suggest that delivering in vivo an MsC-conditioned medium(i.e.,the medium collected from MsC cultures after at least 3 days of exposure)exerts neuroprotective and anti-inflammatory effects in a variety of neurological conditions.

关键词： protective clinical collective

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