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Upconversion luminescence and temperature sensing performance of Er^(3+) ions doped self-activated KYb(MoO_(4.)_(2) phosphors

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Journal of Rare Earths 2024年第8期42卷 1507-1513,I0004页

作者： Ye tong Wenpeng Liu Shoujun Ding School of Microelectronics and Data Science Anhui University of TechnologyMaanshan243002China Advanced Laser Technology Laboratory of Anhui Province Hefei230037China Anhui Institute of Optics and Fine Mechanics Chinese Academy of SciencesHefei230031China

In this work,a series of self-activated KYb(MoO_(4.)_(2) phosphors with various x at% Er^(3+) doping concentrations(x=0.5,1,3,5,8,10,15) was synthesized by the solid-state reaction *** phase structure of the as-prepared samples was analyzed by X-ray diffraction(XRD),XRD Rietveld refinement and Fourier transform infrared(FT-IR) *** as-prepared samples retain the orthorhombic structure with space group of Pbcn even Er^(3+) doping concentration up to 15 at%.High-purity upconversion(UC) green emission with green to red intensity ratio of 55 is observed from the as-prepared samples upon the excitation of 980 nm semiconductor laser and the optimum doping concentration of Er^(3+) ions in the self-activated KYb(MoO_(4.)_(2) host is revealed as 3 at%.The strong green UC emission is confirmed as a two-photon process based on the power-dependent UC *** addition,the fluorescence intensity ratios(FIRs) of the two thermally-coupled energy levels,namely ^(2)H_(11/2) and ^(4.S_(3/2).of Er^(3+) ions were investigated in the temperature region 300-570 K to evaluate the optical temperature sensor behavior of the *** maximum relative sensitivity(S_(R)) is determined to be 0.0069 K^(-1) at300 K and the absolute sensitivity(S_(A)) is determined to be 0.0126 K^(-1) at 300 *** S_(A) of self-activated KYb(MoO_(4.)2:Er^(3+)is almost twice that of traditional KY(MoO_(4.)2:Er^(3+)/Yb^(3+)codoping *** results demonstrate that Er^(3+) ions doped self-activated KYb(MoO_(4.)2 phosphor has promising application in visible display,trademark security and optical temperature sensors.

关键词： Er^(3+)ions doped KYb(MoO_(4.)_(2) Self-activated phosphors Upconversion luminescence Solid-state reaction method Optical temperature sensors Rare earths

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Interaction mechanism of cyanide with pyrite during the cyanidation of pyrite and the decyanation of pyrite cyanide residues by chemical oxidation

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 1996-2005页

作者： Wenwen Han Hongying Yang Linlin tong Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

The toxic cyanides in cyanide residues produced from cyanidation process for gold extraction are harmful to the *** is one of the main minerals existing in cyanide *** this work,the interaction of cyanide with pyrite and the decyanation of pyrite cyanide residue were *** revealed that high pH value,high cyanide concentration,and high pyrite dosage promoted the interaction of cyanide with *** cyanidation of pyrite was pseudo-second-order with respect to *** decyanation of pyrite cyanide residue by Na_(2)SO_(3)/air oxidation was *** cyanide removal efficiency was 83.9% after 1 h of reaction time under the optimal conditions of pH value of 11.2,SO_(3)^(2-) dosage of 22 mg·g^(-1),and air flow rate of 1.4. L·min^(-1).X-ray photoelectron spectroscopy analysis of the pyrite samples showed the formation of Fe(Ⅲ)and FeSO_(4. during the cyanidation *** cyanide that adsorbed on the pyrite surface after cyanidation mainly existed in the forms of free cyanide(CN^(-))and ferrocyanide(Fe(CN)_(6)^(4.)),which were effectively removed by Na_(2)SO_(3)/air *** the decyanation process,air intake promoted pyrite oxidation and weakened cyanide adsorption on the pyrite *** study has practical significance for gold enterprises aiming to mitigate the environmental impact related to cyanide residues.

关键词： pyrite cyanide decyanation sodium sulfite/air oxidation cyanide residue

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Highly efficient and stable 2D/3D perovskite solar cells based on surface reconstruction and energy level alignment

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Science China Chemistry 2024年第9期67卷 3083-3090页

作者： Qiaohui Li Hang Liu tong Zhou Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-PlasticsQingdao University of Science and TechnologyQingdao 266042China The Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer Materials Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China

Realizing simultaneous adjustment of energy levels and work functions in two-dimensional/three-dimensional(2D/3D)perovskite solar cells(PSCs)is a ***,a pseudohalide 3,5-bis(trifluoromethyl)benzylammonium tetrafluoroborate(TFPMABF_(4.)was used to react with unreacted Pb I2on the surface of 3D bulky perovskite to form a mixed halide of 2D perovskite denoted(TF-PMA)_(2)FA_(2)Pb_(3)I_(8)(BF_(4.)_(2).This novel 2D/3D perovskite enables the simultaneous adjustment of energy levels and work functions on the surface of active *** to the significantly enhanced quality of 2D/3D perovskite film,decreased surface defects and increased charge carrier lifetime,the 2D/3D PSCs exhibit an outstanding power conversion efficiency(PCE)of 25.15%and a high V_(OC)of 1.194.***,2D/3D PSCs exhibit remarkable enhancements in environmental stability,unencapsulated devices retaining more than 90%of their initial PCE at 50%humidity for 2,280 h.

关键词： 2D/3D perovskite perovskite solar cells organic spacers energy levels alignment

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d-Orbital steered FeN_(4.moiety through N,S dual-site adjustation for zinc-air flow battery

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Journal of Energy Chemistry 2024年第5期92卷 8-15页

作者： Chunzhu Bao Mingwei tong Xueli Li Zhonghua Xiang State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

The implementation of pristine covalent organic polymer(CO_(2)P)with well-defined structure as air electrode may spark fresh vitality to rechargeable zinc-air flow batteries(ZAFBs),but it still remains challenges in synergistically regulating their electronic states and structural porosity for the great device ***,we conquer these issues by exploiting N and S co-doped graphene with COP rich in metal-ligand nitrogen to synergistically construct an effective catalyst for oxygen reduction reaction(ORR).Among them,the N and S co-doped sites with high electronegativity properties alter the number of electron occupations in the d orbital of the iron centre and form electron-transfer bridges,thereby boosting the selectivity of the ORR-catalysed four-electron ***,the introduction of COP materials aids the formation of pore interstices in the graphene lamellae,which both adequately expose the active sites and facilitate the transport of reactive *** from the synergistic effect,as-prepared catalyst exhibits excellent half-wave potentials(E_(1/2)=912 mV)and stability(merely 8.8%drop after a long-term durability test of 50000 s).Further,ZAFBs assembled with the N/SG@CO_(2)P catalyst demonstrate exceptional power density(163.8 mW cm^(-2))and continuous charge and discharge for approximately 14. h at 10 mA cm^(-2),outperforming the noble-metal benchmarks.

关键词： Nitrogen/sulfurdual sites Metal-coordinated nitrogen sites Covalent organic polymer Oxygen reduction reaction Zn-airflow battery

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Photoinduced Bending and Curling Motions in Molecular Microcrystals of Naphthyl Meldrum’s Acid Derivative Based on E-to-Z Photoisomerization

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Chemical Research in Chinese Universities 2024年第5期40卷 907-913页

作者： ZHANG Xiaowen XU Tianyi ZHANG Chenchen tong Fei Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237P.R.China

Dynamic photoresponsive molecular crystals are promising candidates for making intelligent devices and materials in the ***,we synthesized a new photoactive molecule(E)-2,2-dimethyl-5-[3-(naphthalen-1-yl)allylide]-1,3-dioxane-4.6-dione[(E)-DNADD]that undergoes an E-to-Z photoisomerization in both liquid solution and solids when exposed to visible light(4.5 nm).Compared to the bulk crystals,the photoresponsive behavior in microcrystals was profoundly *** crystalline(E)-DNADD microplate crystals exhibit robust motions,including bending,curling,and coiling under light *** photoproduct conversion of the photochemical reaction in the microplate is no more than 20%,while the large bending curvature of the coiled illuminated samples was estimated at approximately 150–300 mm−1,comparable to some photoactive *** results indicate that shrinking crystal dimensions can boost the photoresponses in molecular crystals and provide a facile strategy for developing dynamic molecular crystals at the microscopic scale.

关键词： Photochemistry Molecular crystal E-to-Z photoisomerization Photoinduced motion

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Health-oriented strategies are needed to optimize China’s 2025 clean air action plan

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Science Bulletin 2024年第13期69卷 2007-2008页

作者： Tao Xue Ning Kang Wei Wan tong Zhu Institute of Reproductive and Child Health/National Health Commission Key Laboratory of Reproductive Health and Department of Epidemiology and Biostatistics/Ministry of Education Key Laboratory of Epidemiology of Major Diseases(PKU) School of Public HealthPeking University Health Science CentreBeijing 100191China State Environmental Protection Key Laboratory of Atmospheric Exposure and Health Risk Management Center for Environment and HealthPeking UniversityBeijing 100871China Advanced Institute of Information Technology Peking UniversityHangzhou 311215China Clean Air Asia Beijing 100600China College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China

Recently,China’s State Council issued the Continuous Improvement of Air Quality Action Plan(hereafter,the third action plan),which follows the Air Pollution Prevention and Control Action Plan(2013–2017)(hereafter,the first action plan)and the Three-Year Action Plan for Winning the Blue Sky Defense Battle(2018–2020)(hereafter the second action plan).The first two action plans yielded nationwide health benefits[1–3],from improving lung function[4.to saving medical expenditures[5].Based on our previous estimates[6],due to reductions in the fine particulate matter(PM2.5)level,implementation of the first and second action plans was expected to increase life expectancy by 2.11 and 3.68 months.

关键词： action hereafter nationwide

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An automatic Q-factor matching method for eliminating 77%of the ZRO of a MEMS vibratory gyroscope in rate mode

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Microsystems & Nanoengineering 2024年第3期10卷 35-48页

作者： Jingbo Ren tong Zhou Yi Zhou Yixuan Li Yan Su School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210000China

Mismatching quality factors(Q-factors)is one of the main factors causing zero-rate output(ZRO)in degenerate(DE)Micro-Electro-Mechanical Systems(MEMS)vibratory *** eliminate the ZRO of the DE MEMS gyroscope,this study introduces a method for real-time identification and automatic matching of Q-factors in rate *** leveraging the vibration characteristics of the DE MEMS vibratory gyroscope in rate mode,dedicated online test methods are designed to determine the Q-factors for both the drive and sense modes,enabling online identification of the Q-factor ***,an automatic Q-factor matching system is designed utilizing the mechanical-thermal dissipation mechanism of the resistive *** effectiveness of this proposed method is validated through simulations and experiments conducted on a MEMS disk resonator gyroscope(DRG).The results show a measurement error within 4.for Q-factor identification,and automatic Q-factor matching effectively reduces the ZRO by 77%.Employing this automatic Q-factor matching method successfully reduces the ZRO that is caused by the mismatching of Q-factors in the MEMS DRG from 0.11°/s to 0.025°/s and improves the bias instability(BI)from 0.4.°/s to 0.19°/s.

关键词： matching mode method

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Carbon fiber reinforced liquid crystalline elastomer composites:a dual exploration in strength augmentation and transformation flexibility through 4. printing

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International Journal of Smart and Nano Materials 2024年第2期15卷 312-329页

作者： Yuliang Xia tong Mu Yanju Liu Jinsong Leng Centre for Composite Materials and Structures Harbin Institute of Technology(HIT)HarbinPeople's Republic of China Department of Astronautical Science and Mechanics Harbin Institute of Technology(HIT)HarbinPeople's Republic of China

Liquid Crystal Elastomers(LCEs)are renowned for their reversible deformation ***,enhancing their mechanical strength while retaining such flexibility has posed a considerable *** overcome this,we utilized 4. printing to develop an innovative composite of LCE with carbon fiber fabric(LCEC).This approach has notably increased the tensile strength of LCE by eightfold,all the while maintaining its exceptional capacity for reversible *** adjusting the alignment angle between carbon fiber and the LCE printing direction from 0°to 90°,the LCEC demonstrates an array of new deformation patterns,including bending,twisting,wrapping,and S-shaped transformations,which are distinct from pure LCE *** study unveils that LCE composites exhibit deformation processes markedly different from their pure material counterparts,with the ability of pure LCE to sustain tensile strains exceeding 1900%.These findings,previously undocumented and unexplored,represent a substantial contribution to the field of smart *** finite element analysis,we explored the carbon fiber and LcE matrix dynamics,revealing bending mechanics in *** combined experimental and simulation approach yields crucial insights for crafting durable,high-strength LCECs with diverse deformational properties,advancing smart material technology.

关键词： Liquid crystal elastomer composites 4. printing Smart materials

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Lightweight Si_(3)N_(4.@SiO_(2) ceramic foam for thermal insulation and electromagnetic wave transparency

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Nano Research 2024年第5期17卷 4298-4306页

作者： Zongwei tong Xiangjie Yan Yuexiang Wang Kexun Li Weihai Ma China-Blarus Belt and Road Joint Laboratory on Electromagnetic Environment Effect the 33rd Research Institute of ChinaElectronics Technology Group CorporationTaiyuan 030032China Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education School of Material Science and EngineeringTianjin UniversityTianjin 300072China Department of Materials Science and Engineering Jinzhong UniversityJinzhong 030619China

Increasing porosity is one of the most direct ways to improve the thermal insulation and dielectric properties of *** now,many wet methods for preparing Si_(3)N_(4. ceramic foams usually face the problems of complex rheology,long period,and expensive cost,and the reported pore sizes of Si_(3)N_(4. ceramic foams are typically micron-grade,resulting in a lack of competitiveness in thermal insulation and wave-transparent *** this paper,the Si_(3)N_(4.@SiO_(2) ceramic foams were prepared using an efficient dry-method,which combined three processes of low temperature chemical vapor deposition(LTCVD),template,and isostatic *** method has the advantages of simple operation and short preparation period,and can realize near-net size molding and mass *** addition,the evolution mechanisms of honeycomb microstructure and composition of Si_(3)N_(4.@SiO_(2) ceramic foam during sintering were studied by chemical reaction *** as-prepared Si_(3)N_(4.@SiO_(2) ceramic foam possesses low density(0.377 g·cm^(-3)),high compressive strength(7.5 MPa),low thermal conductivity(0.0808 W·m^(-1)·K^(-1)),and excellent dielectric properties(ε4. ceramic radome to improve its thermal insulation and electromagnetic wave transparency performances.

关键词： silicon nitride ceramic foam honeycomb microstructure dielectric properties thermal insulation

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Review of the research on the development and utilization of clay-type lithium resources

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Particuology 2024年第4期87卷 46-53页

作者： Ruiqi Xie Zhihui Zhao Xiong tong Xian Xie Qiang Song Peiqiang Fan Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming650093China Yunnan Engineering Research Center for Metal Tailings Resource Utilization Kunming650093China

Since the demands for lithium have been in explosive growth recently and several great clay lithium resources were founded in China,the development and utilization of clay-type lithium resources become a hot *** order to provide a guidance for the concentration and extracting lithium of clay-type lithium resources,this review systematically summarized the main types and characteristics of clay-type lithium resources and the research status of lithium extraction from clay lithium ***,the flotation research status of the main mineral of clay lithium ore was also ***,we discussed the difficulties in the development and utilization of clay-type lithium ore and put forward the subsequent research *** paper can provide a guidance for the con-centration and extracting lithium of clay-type lithium resources in the future.

关键词： Clay lithium Clay mineral flotation Lithium extraction Leaching

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