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Elucidating elusive quaternary selenide EuCeCuSe3:Synthesis,crystal structure,properties and theoretical studies

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Journal of Rare Earths 2024年第1期42卷 163-171,I0006页

作者： Maxim V.Grigoriev Anna V.Ruseikina Maxim S.Molokeev Vladimir A.Chernyshev Aleksandr S.Aleksandrovsky Alexander S.Krylov Svetlana N.Krylova Nikolai P.Shestakov Dmitriy A.Velikanov Alexander A.Garmonov Alexey V.Matigorov Evgeny A.Ostapchuk thomas Schleid Damir A.Safin Laboratory of Theory and Optimization of Chemical and Technological Processes University of TyumenVolodarskogo Str.6625003TyumenRussian Federation Kirensky Institute of Physics Federal Research Center KSC SB RASAkademgorodok 50 Bld.38660036KrasnoyarskRussian Federation Department of Physics Far Eastern State Transport UniversitySerysheva Str.47680021KrasnoyarskRussian Federation Institute of Natural Sciences and Mathematics Ural Federal University Named After the First President of Russia B.N.YeltsinMira Str.19620002EkaterinburgRussian Federation Department of Photonics and Laser Technology Siberian Federal UniversitySvobodnii Ave.79660079KrasnoyarskRussian Federation Institute of Physics and Technology University of TyumenVolodarskogo Str.6625003 TyumenRussian Federation Institute for Inorganic Chemistry University of StuttgartPfaffenwaldring 55D-70569StuttgartGermany Scientific and Educational and Innovation Center for Chemical and Pharmaceutical Technologies Ural Federal University named after the First President of Russia B.N.YeltsinMira Str.19620002 EkaterinburgRussian Federation University of Tyumen Volodarskogo Str.6625003TyumenRussian Federation

We report on the novel heterometallic quaternary selenide EuCeCuSe3,the fabrication of which has been a challenge until this *** structure of the reported selenide was elucidated from the powder X-ray diffraction data,which revealed the formation of EuCeCuSe3with excellent yield(96.7%)accompanied with a minor fraction of CeSe2(3.3%),and was best solved in orthorhombic space group Pnma with the BaLaCuS3structural ***,the crystal structure of the title compound completes the row of the heterometallic quaternary selenides EuRECuSe3(RE=La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,er,Tm,Yb,Lu,Y),of which the cerium-based derivative exclusively belongs to the BaLaCuS3structural *** distortion of the CuSe4polyhedron was compared for the whole series of EuRECuSe3compounds using theτ4-descriptor for four coordinated ions,which revealed the highest degree of distortion for the Ce3+-containing selenide,followed by the La3+-based ***,the crystallographic and geometrical parameters of the reported selenide were discussed in comparison to the Ce3+-based sulfides SrCeCuS3and *** initio calculations of the crystal structure,a phonon spectrum and elastic constants for the crystal of EuCeCuSe3were also *** types and wavenumbers of fundame ntal modes were determined and the involvement of ions participating in the phonon modes was *** experimental IR spectrum of the reported selenide was interpreted and found to be in agreement with the calculated *** experimental direct band gap of EuCeCuSe3was measured to be 1.36 eV that is consistent with the concept of its origin due to interband transitions between orbitals emerging mainly from 4f(valence band)and 5d(conduction band)levels of the Eu2+*** dependence of the Young’s modulus on the direction demonstrates the anisotropy of the elastic properties,while the Vickers hardness for EuCeCuSe3was calculated to be 5.2 ***,the title compound is paramagnetic above 4 K.

关键词： Quaternary selenide Synthesis Crystal structure Ab initio calculations Magnetic measurements Spectroscopy

High birth weight is a risk factor of dental caries increment during adolescence in Sweden

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Open Journal of Stomatology 2013年第9期3卷 42-51页

作者： Annika Julihn Ulrika Molund Emma Drevsater thomas Modéer Division of Pediatric Dentistry Department of Dental MedicineKarolinska InstituteHuddingeSweden Specialist Clinic of Pediatric Dentistry Specialist Dental Care in Vastra GotalandGoteborgSweden

This study aimed to assess whether birth weight is associated with dental caries during the teenage period. In this register-based cohort study, all children of 13 yrs of age (n = 18,142) who resided in the county of Stockholm, Sweden, in 2000 were included. The cohort was followed until individuals were 19 yrs of age. Information regarding dental caries was collected from the Public Health Care Administration in Stockholm. Data concerning prenatal and perinatal factors and parental socio-demographic determinants were collected from the Swedish Medical Birth Register and National Registers at Statistics Sweden. The final logistic regression model showed that birth weight (≥4000 g), adjusted for potential confounders, was significantly associated with caries increment (DMFT ≥ 1) between 13 and 19 yrs of age (OR: 1.29, 95% CI = 1.13 - 1.48). The relatively enhanced risk OR was further increased from 1.29 to 1.52 in sub- jects with birth weight (≥4600 g). On the contrary, subjects with birth weight (er risk (OR: 0.67, 95% CI = 0.50 - 0.89) for exhibiting caries experience (DMFT ≥4) at 19 yrs of age. In conclusion, birth weight can be regarded as a predictor for dental caries and birth weight (≥4000 g) is especially a risk factor for caries increment during adolescence.

关键词： Adolescents Birth Weight Cohort Study Dental Caries Longitudinal Study Predictor Risk Assessment Risk Factor

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亚洲应活跃国内资本市场

海外经济评论 2007年第18期 30-31页

作者： thomas Schi11er 标准普尔亚太区总裁

七国集团（G7）财政部长鼓励亚洲及其它新兴市场促进国内资本市场的发展，这项举措应该受到赞许。它突显出一个令许多亚洲国家头痛的问题，而正是这个问题束缚了这些国家追求长期可持续高增长的能力。

关键词：国内资本市场亚洲国家新兴市场财政部长七国集团可持续头痛

Sparse time-frequency representation of nonlinear and nonstationary data Dedicated to Professor Shi Zhong-Ci on the Occasion of his 80th Birthday

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Science China Mathematics 2013年第12期56卷 2489-2506页

作者： HOU thomas Yizhao SHI ZuoQiang Department of Computing and Mathematical Sciences California Institute of Technology Mathematical Sciences Center Tsinghua University

Adaptive data analysis provides an important tool in extracting hidden physical information from multiscale data that arise from various applications. In this paper, we review two data-driven time-frequency analysis methods that we introduced recently to study trend and instantaneous frequency of nonlinear and nonstationary data. These methods are inspired by the empirical mode decomposition method （EMD） and the recently developed compressed （compressive） sensing theory. The main idea is to look for the sparsest representation of multiscale data within the largest possible dictionary consisting of intrinsic mode functions of the form {a（t） cos（0（t））}, where a is assumed to be less oscillatory than cos（θ（t）） and θ ＇≥ 0. This problem can be formulated as a nonlinear ι0 optimization problem. We have proposed two methods to solve this nonlinear optimization problem. The first one is based on nonlinear basis pursuit and the second one is based on nonlinear matching pursuit. Convergence analysis has been carried out for the nonlinear matching pursuit method. Some numerical experiments are given to demonstrate the effectiveness of the proposed methods.

关键词： sparse representation time-frequency analysis data-driven

Jade Myths and the Formation of Chinese Identity

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Journal of Literature and Art Studies 2017年第4期7卷 377-398页

作者： YE Shu-xian LIU Wan-er Shanghai Jiaotong University Shanghai China Beijing Institute of Technology Beijing China

Reality is constructed by societies, whose process must be analyzed by the sociology of knowledge. The ＂reality＂, taken as granted by the public, has sharp contrast from one society to another. By Peter Berger and thomas Luckman： The Social Construction of Reality Chinese civilization is the only surviving one that has a continual history that lasts for several thousand years since the Stone Age. What＇s the secret of its lasting cultural vitality？ How can it live through numerous military conflicts and political transitions and still firmly hold a large population of various ethnics within its administration？ A long-established cultural centripetal force, i.e. cultural identity shared by multi parties, shall be the key to former questions. According to current focus of cultural research, this force is termed as ＂Chinese identity＂, which explores the formation and continuation of Chinese civilization from the perspective of cultural identity. What is cultural identity？ A simplified answer is：

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Particle-size-dependent upconversion luminescence of NaYF4:Yb,er nanoparticles in organic solvents and water at different excitation power densities

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Nano Research 2018年第12期11卷 6360-6374页

作者： Marco Kraft Christian Würth Verena Muhr thomas Hirsch Ute Resch-Genger Federal Institute for Matefiab Research and Testing (BAM) Division1.2BiophotonicsRichard-Willstaetter-Str.1112489BerlinGermany Institute of Analytical Chemistry Chemo-and BiosensorsUniversity of Regensburg93040RegensburgGermany

A systematic study of the luminescence properties of monodisperse β-NaYF4: 20% Yb3+, 2% er3+ upconversion nanoparticles (UCNPs) with sizes ranging from 12–43 nm is presented utilizing steady-state and time-resolved fluorometry. Special emphasis was dedicated to the absolute quantification of size- and environment-induced quenching of upconversion luminescence (UCL) by high-energy O–H and C–H vibrations from solvent and ligand molecules at different excitation power densities (P). In this context, the still-debated population pathways of the 4F9/2 energy level of er3+ were examined. Our results highlight the potential of particle size and P value for color tuning based on the pronounced near-infrared emission of 12 nm UCNPs, which outweighs the red er3+ emission under “strongly quenched” conditions and accounts for over 50% of total UCL in water. Because current rate equation models do not include such emissions, the suitability of these models for accurately simulating all (de)population pathways of small UCNPs must be critically assessed. Furthermore, we postulate population pathways for the 4F9/2 energy level of er3+, which correlate with the size-, environment-, and P-dependent quenching states of the higher er3+ energy levels.

关键词： upconversion nanoparticle quenching diameter water cyclohexane

Physiological and Growth Responses of C_3 and C_4 Plants to Reduced Temperature When Grown at Low CO_2 of the Last Ice Age

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Journal of Integrative Plant Biology 2008年第11期50卷 1388-1395页

作者： Joy K.Ward David A.Myers Richard B.thomas Department of Ecology and Evolutionary Biology University of Kansas Department of Biology West Virginia University

During the last ice age, CO2 concentration （[CO2]） was 180-200 umol/mol compared with the modern value of 380 umol/mol, and global temperatures were -8 ℃ cooler. Relatively little is known about the responses of C3 and C4 species to longterm exposure to glacial conditions. Here Abutilon theophrasti Medik. （C3） and Amaranthus retroflexus L. （C4） were grown at 200 umol/mol CO2 with current （30/24℃） and glacial （22/16℃） temperatures for 22d. Overall, the C4 species exhibited a large growth advantage over the C3 species at low [CO2]. However, this advantage was reduced at low temperature, where the C4 species produced 5x the total mass of the C3 species versus 14x at the high temperature. This difference was due to a reduction in C4 growth at low temperature, since the C3 species exhibited similar growth between temperatures. Physiological differences between temperatures were not detected for either species, although photorespiration/net photosynthesis was reduced in the C3 species grown at low temperature, suggesting evidence of improved carbon balance at this treatment. This system suggests that C4 species had a growth advantage over C3 species during low [CO2] of the last ice age, although concurrent reductions in temperatures may have reduced this advantage.

关键词： Abutilon theophrasti Amaranthus retroflexus C3 species C4 species climate change low CO2 low temperature photorespiration Pleistocene.

TWISTED DWARF 1 Associates with BRASSINOSTerOID-INSENSITIVE 1 to Regulate Early Events of the Brassinosteroid Signaling Pathway

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Molecular Plant 2016年第4期9卷 582-592页

作者： Baolin Zhao Minghui Lv Zengxiu Feng thomas Campbell Emmanuel Liscum Jia Li Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations School of Life Sciences Lanzhou University Lanzhou 730000 China Division of Biological Sciences University of Missouri Columbia MO 65211 USA C.S. Bond Life Sciences Center University of Missouri Columbia MO 65211 USA

A genome-wide screen for mutants showing altered brassinosteroid （BR） sensitivity or bril-like phenotypes resulted in the identification of two new mutant alleles of TWISTED DWARF 1 （TWD1）, twd1-4, and twdl-5. Pre- vious studies indicated that TWD1, also named as ULTRACURVATA 2 or FKBP42, associates with auxin efflux transporters and is essential for their biological functions. Although earlier reports showed that BR signaling is downregulated in twdl, how TWD1 is integrated in BR signaling has not been elucidated. Here, we provide ge- netic and biochemical evidence demonstrating that TWD1 interacts with the BR receptor BRI1 in vivo in a BR- independent manner. Further analyses indicated that TWD1 modulates the BR signal transduction not by altering er quality control or protein abundance of BRI1; instead, TWD1 appears to be critical in BR- induced interaction of BRI1 and its co-receptor BAK1, as well as BR-induced phosphorylation of these two proteins. These results provide better understanding of the early events of the BR signaling pathway.

关键词： BAK1 brassinolide brassinosteroid BRI1 TWD1

A high‐performance transition‐metal phosphide electrocatalyst for converting solar energy into hydrogen at 19.6% STH efficiency

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Carbon Energy 2023年第1期5卷 206-217页

作者： Hua Zhang Abuduwayiti Aierke Yingtang Zhou Zitao Ni Ligang Feng Anran Chen thomas Wågberg Guangzhi Hu Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental SciencesSchool of Materials and EnergyYunnan UniversityKunmingPeople's Republic of China School of Energy and Environment Science Yunnan Normal UniversityKunmingPeople's Republic of China National Engineering Research Center for Marine Aquaculture Marine Science and Technology CollegeZhejiang Ocean UniversityZhoushanPeople's Republic of China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhouPeople's Republic of China Department of Physics UmeåUniversityUmeåSweden

The construction of high-efficiency and low-cost non-noble metal bifunctional electrocatalysts for water electrolysis is crucial for commercial large-scale application of hydrogen ***,we report a novel strategy with erbiumdoped NiCoP nanowire arrays in situ grown on conductive nickel foam(er-NiCoP/NF).Significantly,the developed electrode shows exceptional bifunctional catalytic activity,which only requires overpotentials of 46 and 225 mV to afford a current density of 10 mAcm^(−2) for the hydrogen evolution reaction(Her)and the oxygen evolution reaction(Oer),*** functional theory calculations reveal that the appropriate er incorporation into the NiCoP lattice can significantly modulate the electronic structure with the d-band centers of Ni and Co atoms by shifting to lower energies with respect to the Fermi level,and optimize the Gibbs free energies of Her/Oer intermediates,thereby accelerating water-splitting *** assembled as a solar-driven overall water-splitting electrolyzer,the as-prepared electrode shows a high and stable solar-to-hydrogen efficiency of 19.6%,indicating its potential for practical storage of intermittent energy.

关键词： bifunctional electrocatalysts electronic regulation hydrogen evolution reaction oxygen evolution reaction solar-to-hydrogen efficiency