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Effects of europium concentration on luminescent and scintillation performance of Cs_(0.2)Rb_(0.8)Ca_(1-x)Eu_(x)Br_(3)(0≤x≤0.08)crystals

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Journal of Rare Earths 2022年第1期40卷 29-33页

作者： n.V.Rebrova A.yu.Grippa I.A.Boiaryntseva P.Berastegui T.E.Gorbacheva yu.n.Datsko A.L.Rebrov C.Dujardin R.Calà L.Martinazzoli E.Auffray V.V.Kononets Institute for Scintillation Materials National Academy of Sciences of UkraineNauky Avenue 6061072KharkovUkraine Department of Chemistry Angstrom LaboratoryInorganic ChemistryUppsala University.PO.Box 583.75121.UppsalaSweden Claude Bernard Lyon 1 University CNRSInstitute of Light and MatterUMR 5306F-69100 VilleurbanneFrance The University of Milano-Bicocca Piazza dell'Ateneo Nuovo1-20126Milano.Italy CERn EP DepartmentP.0.Box 1211Geneva 23Switzerland

A series of Cs_(0.2)Rb_(0.8)Ca_(1-x)Eu_(x)Br_(3)(0≤x≤0.08)crystals doped with different concentrations of Eu^(2+)were grown using the Bridgman-Stockbarger *** work describes the influence of Eu^(2+)concentration on the luminescent and kinetic properties of Cs_(0.2)Rb_(0.8)Ca_(1-x)Eu_(x)Br_(3) crystals,as well as on their scintillation *** maximum in the radioluminescence spectra of these crystals shifts from 439 to446 nm with increasing europium *** scintillation decay times of Cs_(0.2)Rb_(0.8)Ca_(1-x)Eu_(x)Br_(3) lengthen with the Eu^(2+)*** best light output of 33600photons/MeV is obtained for Cs_(0.2)Rb_(0.8)Ca_(0.93)Eu_(0.07)Br_(3),and the best energy resolution of 6.9%is found for Cs_(0.2)Rb_(0.8)Ca_(0.94)Eu_(0.06)Br_(3).

关键词： Inorganic material Crystal growth Luminescence Rare-earth doped scintillator X-ray and gamma-ray spectroscopies

Effects of physiological integration on defense strategies against herbivory by the clonal plant Alternanthera philoxeroides

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Journal of Plant Ecology 2019年第4期12卷 662-672页

作者： Rubén Portela Bi-Cheng Dong Fei-Hai yu Rodolfo Barreiro Sergio R.Roiloa BioCost Group Biology DepartmentUniversidade da CoruñaA Coruña 15071Spain School of nature Conservation Beijing Forestry UniversityBeijing 100083China Institute of Wetland Ecology&Clone Ecology/Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation Taizhou UniversityTaizhou 318000China

Aims The plant-herbivore interaction is one of the most fundamental inter-actions in *** are sessile organisms,and consequently rely on particular strategies to avoid or reduce the negative impact of ***,we aimed to determine the defense strategies against insect herbivores in the creeping invasive plant Alternanthera *** We tested the defense response of *** to herbivory by a leaf-feeding specialist insect Agasicles hygrophila and a pol-yphagous sap-feeding insect Planococcus *** also tested the mechanisms triggering defense responses of *** by including treatments of artificial leaf removal and jasmonic acid ***,we examined the effect of physiological integration on these defense *** Findings The combination of artificial leaf removal and jasmonic acid appli-cation produced a similar effect to that of leaf-feeding by the real *** integration influenced the defense strat-egies of *** against herbivores,and increased biomass allocation to aboveground parts in its apical ramets damaged by real *** study highlights the importance of physio-logical integration and modular plasticity for understanding the consequences of herbivory in clonal plants.

关键词： Agasicles hygrophila alligator weed clonal integration herbivory Planococcus minor

Cross-linking enhanced room-temperature phosphorescence of carbon dots

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SmartMat 2022年第2期3卷 337-348页

作者： Boyang Wang Zhen Sun Jingkun yu Geoffrey I.n.Waterhouse Siyu Lu Bai Yang Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhouChina School of Chemical Sciences The University of AucklandAucklandNew Zealand State Key Lab of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchunChina

Currently,there is a strong drive to discover alternative materials that exhibit room-temperature phosphorescence(RTP)for displays,bioimaging,and data ***,these materials should be nontoxic,cheap,and possess controllable photoluminescent *** dots(CDs)possess each of these characteristics,but to date,less attention has been paid to their RTP ***,we synthesized a series of CDs by self-crosslinking and carbonization of *** resultant CDs were luminescent and exhibited a bright,micro-second afterglow *** increase the RTP,a second microwave processing step was used to coat the CDs with polyvinyl alcohol(PVA),polyacrylamide(PAM),or tetraethyl orthosilicate(TEOS),producing CDs@PVA,CDs@PAM,and CDs@TEOS *** core-shell structure acted to enhance crosslinking at the surface of the CDs to boost the RTP,creating abundant energy levels for intersystem *** situ X-ray photoelectron spectroscopy verified electron transfer during ***,we present a design rule that can be used to tune the quantum yields and RTP lifetime of CDs,based on the effective stabilization of triplet excited states through the extent and strength of *** simple strategy provides a flexible route for guiding the further development of CDs with tailored RTP properties for various applications.

关键词： carbon dots crosslink-enhanced emission effect phosphorescence mechanism polymers room-temperature phosphorescence

Simultaneous quantification of fifty-one odor-causing compounds in drinking water using gas chromatography-triple quadrupole tandem mass spectrometry

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Journal of Environmental Sciences 2019年第5期31卷 100-110页

作者： Chunmiao Wang Jianwei yu Qingyuan Guo yu Zhao nan Cao Zhiyong yu Min Yang Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences College of Environmental Science & Engineering Yancheng Institute of Technology Beijing Waterworks Group

A wide range of compounds with various structural features can cause taste and odor(T&O)problems in drinking water. It would be desirable to determine all of these compounds using a simple analytical method. In this paper, a sensitive method combining liquid–liquid extraction(LLE) with gas chromatography-triple quadrupole tandem mass spectrometry(GC–MS/MS)was established to simultaneously analyze 51 odor-causing compounds in drinking water,including organic sulfides, aldehydes, benzenes, phenols, ethers, esters, ketones, nitrogenous heterocyclic compounds, 2-methylisoborneol and geosmin. Three deuterated analogs of target analytes, dimethyl disulfide-d6, benzaldehyde-d6 and o-cresol-3,4,5,6-d4,were used to correct the variations in recovery, and five isotope-labeled internal standards(4-chlorotoluene-d4, 1, 4-dichlorobenzene-d4, naphthalene-d8, acenaphthene-d10, phenanthrene-d10 respectively) were used prior to analysis to correct the variations arising from instrument fluctuations and injection errors. The calibration curves of the target compounds showed good linearity(R2> 0.99, level = 7),and method detection limits(MDLs) below 1/10 of the odor threshold concentrations were achieved for most of the odorants(0.10–20.55 ng/L). The average recoveries of most of the analytes in tap water samples were between 70% and 120%, and the method was reproducible(RSD n = 7). Additionally, concentrations of odor-causing compounds in water samples collected from three drinking water treatment plants(DWTPs) were analyzed by this *** to the results, dimethyl trisulfide, dimethyl disulfide and indole were considered to be the key odorants responsible for the swampy/septic odor. 2-Methylisoborneol and geosmin were detected as the main odor-causing compounds for musty/earthy odor in DWTP B.

关键词： Odor-causing compounds Drinking water GC–MS/MS High-throughput detection

Effect of low-temperature ausforming on bainitic transformation and mechanical properties in ultrahigh-strength bainitic steel

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Journal of Iron and Steel Research International 2023年第9期30卷 1843-1853页

作者： Tian-yu Zhang Ling-yu Wang yu Wang Jun Hu Hong-shuang Di Wei Xu State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina

Low-temperature ausforming(LT-AF)prior to bainitic transformation leads to a noticeable acceleration of bainitic transformation kinetics;however,the effect of LT-AF on the retained austenite(RA)features and the resulting mechanical properties is still ***-AF was applied to ultrahigh-strength bainitic steel before *** deformation behavior and the resulting dislocation substructures were investigated by thermomechanical simulator and transmission electron microscopy(TEM).The planar dislocation structures produced during deformation at 350℃ accelerate the bainitic transformation kinetics during isothermal *** effect of LT-AF on the bainitic transformation kinetics and the features of RA was elucidated via dilatometer measurement,TEM,scanning electron microscopy,and X-ray *** is observed that LT-AF not only retains more RA content but also facilitates improved RA *** trend is mainly due to the large amounts of planar dislocations in RA and bainitic laths inherited from undercooled austenite caused by LT-AF,the decrease in bainitic sheaves size,and the increase in filmy RA content compared to the sample without ausforming.A large fraction of filmy RA with high stability and the refinement of bainitic sheaves obtained by LT-AF remarkably enhance the strain hardening capacity and achieve significantly better ductility compared to the directly austempered sample.

关键词： Ultrahigh-strength bainitic steel Bainitic transformation Low-temperature ausforming Retained austenite Strain hardening rate

Editorial--The centennial celebration of *** Chance

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Journal of Innovative Optical Health Sciences 2014年第2期7卷 106-108页

作者： Lin Z.Li He.n.Xu yu Chen Kyung Kang Linda Powers Department of Radiology University of PennsylvaniaUSA Fischell Department of Bioengineering University of MarylandUSA Department of Chemical Engineering University of LouisvileUSA Department of Electric and Computer Engineering Department of Biomedical Engineering Uniuersity of ArizonaUSA

To celebrate the scientific legacy and spirit of the late *** Chance(1913-2010)and his 100thbir thday,t he Brit ton Chance International Symposium on Metabolic Imaging and Spectroscopy was heldat the Perelman School of Medicine,University of Pennsylvania on June 18-19th,*** symposium brought toget her over 200 physicists,engineers,biologists and clinicians from all over the world includingEurope,Asia and north *** latest research innovations and clinical progresses by optical,nuclear magnetic resonance(nMR)and nuclear medicine methods were presented and discussed extensively.

关键词： nMR Chance

Effects of flux on crystal structure and luminescent properties of nitroxides phosphors

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Science China(Physics,Mechanics & Astronomy) 2014年第12期57卷 2228-2234页

作者： XIE An SHI yu WAnG yu Wei School of Materials Science and Engineering Xiamen University of Technology Fushun Electronics Co. Ltd.

Yellow-green-emitting Sr Si2O2n2:Eu2+phosphors were synthesized with Sr2Si O4:Eu2+as *** effects of flux and the concentration of Eu2+on the crystal structure and luminescent properties of the phosphors were *** suggested that the optimal content of flux na2CO3 was 1 wt%and the optimal doping concentration of Eu2+was 0.05 *** emission spectra showed the most intense peaks located at 535 nm which corresponded to the 4f65d→4f7 transition of Eu2+.The excitation spectra showed that these phosphors could be effectively excited by near-ultraviolet and blue light,whichwas consistent with the widely applied output wavelengths of near-ultraviolet and blue-white light-emitting diode(LED)*** the influence of flux on the luminescent properties of Sr Si2O2n2:Eu2+phosphor was analyzed,the X-ray diffraction(XRD)patterns indicated that the flux could help the crystallization of the *** other phases except the triclinic structure of Sr Si2O2n2 were *** thermal stability and the emission intensity of synthesized Sr Si2O2n2:Eu2+phosphor were examined and compared with commercial YAG yellow *** results indicate that the yellow-green-emitting phosphor is a suitable candidate for the fabrication of white LEDs.

关键词： flux nitrogen oxides yellow-green-emitting white LEDs

Multifunctional dopamine-assisted preparation of efficient and stable perovskite solar cells

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Journal of Energy Chemistry 2021年第3期30卷 291-300页

作者： Jiankai Zhang Huangzhong yu School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640GuangdongChina The Key Laboratory of Functional Molecular Solids Ministry of EducationAnhui Normal UniversityWuhu 241000Anhui China Guangdong Provincial Key Laboratory of new and Renewable Energy Research and Development Guangzhou 510640GuangdongChina South China Institute of Collaborative Innovation Dongguan 523808GuangdongChina

Perovskite solar cells(PSCs)show great potential for next-generation photovoltaics,due to their excellent optical and electrical ***,defects existing inside the perovskite film impair both the performance and stability of the *** Pb^(2+),uncoordinated I^(-),and metallic Pb(Pb^(0))are the main defects occur during perovskite film preparation and device operation,due to the volatilization of organic cationic *** these defects is a desirable tas k,because they are non-radiative recombination centers that cause open-circuit voltage(VOC)loss and degradation of the perovskite ***,the multifunctional bioactive compound dopamine(DA)is introduced for the first time to control the perovskite film formation and passivate the uncoordinated Pb^(2+)defects via Lewis acid-base *** Pb^(0) and I^(-)defects are effectively suppressed by the DA *** the same time,the DA treatment results in a stronger crystal orientation along the(110)plane and upshifts the valence band of perovskite closer to the highest occupied molecular orbital(HOMO)of the hole transport layer(2,2’,7,7’-tetrakis(n,n’-di-pmethoxyphenylamine)-9,9’-spirobifluorene,spiro-OMeTAD),which is beneficial for charge separation and transport ***,the stability of MAPbI_(3)(MA=CH_(3)nH_(3))PSCs prepared with the DA additive(especially the thermal stability)is effectively improved due to the better crystallinity and lower number of defect trap states of the perovskite *** optimized MAPbI3 PSCs maintain approximately 90% of their original power conversion efficiency(PCE)upon annealing at 85℃ for 120 *** best performance triple-cation perovskite(Cs_(0.05)(FA_(0.83)MA_(0.17))_(0.95)Pb(I_(0.83)Br_(0.17))_(3))(FA=formamidinium)solar cell with ITO/SnO_(2)/Cs_(0.05)(FA_(0.83)MA_(0.17))_(0.95)Pb(I_(0.83)Br_(0.17))_(3):DA/spiro-OMeTAD/MoO_(3)/Ag(ITO=indium tin oxide)structure shows a PCE of 21.03% with negligible hysteresis,which is

关键词： Perovskite solar cell Dopamine Defect Passivation Performance

Locally repairable codes from combinatorial designs

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Science China(Information Sciences) 2020年第2期63卷 174-188页

作者： yu ZHAnG Haibin KAn Shanghai Key Laboratory of Intelligent Information Processing School of Computer ScienceFudan University Fudan-Zhongan Joint Laboratory of Blockchain and Information Security Shanghai Engineering Research Center of Blockchain Shanghai Institute for Advanced Communication and Data Science

Locally repairable codes（LRCs） were proposed to reduce the repair degree in distributed storage systems. In particular, LRCs with availability are highly desirable for distributed storage systems, since this kind of codes provide the mechanism of local repair for code symbols and parallel reading of hot *** this paper, we propose four types of（n, k, r, t）;LRCs from combinatorial designs. We introduce several constructions of LRCs with strict availability and some constructions of distance-optimal LRCs with information-symbol locality. Most of our constructions in this paper are over F;, i.e., they are suitable for implementation.

关键词： locally repairable codes erasure codes combinatorial designs distributed storage systems codes with availability