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Impact of grain size,Pr3+ concentration and host composition on non-contact temperature sensing abilities of polyphosphate nano- and microcrystals

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Journal of Rare Earths 2019年第8期37卷 812-818,I0001页

作者： S.Gharouel l.marciniak A.lukowiak W.Strek K.Horchani-Naifer m.Férid Research Unit of Rare Earth materials National Research Center in Sciences of MaterialsB.P.95 Hammam-Lif2050Tunisia b Institute of Low Temperature and Structure ResearchPAS Okolna St. 50-422WroclawPoland

In this article,varied praseodymium polyphosphate hosts:mI(li,Na K)Pr(PO3)4 microcrystals and lila1-xPrx(PO3)4(x = 0.01 ^-1)nanocrystals were successfully synthesized by the flux method and the coprecipitation technique,*** size of stoichiometric nanocrystals of liPr(PO3)4 was tuned by the te mpe rature of thermal treatment in range of 35-145 *** order to dete rmine the most suitable material for the non-contact optical thermometric applications,the temperature sensing measurements were carried out by using luminescence intensity ratio(lIR)of emission bands corresponding to the ^3 P1→ ^3H5 and ^3P0→ ^3 H5 electronic transitions of Pr3+ ions into the 123-423 K temperature *** influence of the host material composition of mⅠ(li,Na,K)Pr(PO3)4 microcrystals on the sensitivity of luminescent thermometers was *** is found that the sensitivity of lithium praseodymium polyphosphate is the highest of all micropowders under ***,it is found that the nanocrystals reveal much higher relative sensitivity in respect to the microcrystalline *** highest sensitivity of lIR temperature sensing is found for liPr(PO3)4 nanocrystals(35 nm grain size)in the whole temperature range,reaching 0.283%/K at 164 *** impact of the average grain size on the sensitivity of lIR based thermometers of liPr(PO3)4 nanocrystals was *** is found that the reduction of the grain size from 145 to 35 nm results in the enhancement of the relative sensitivity from0.156 to 0.240%/K at 223 *** it is found that the high dopant concentration possesses favorable influence on the relative sensitivity of lila1-xPrx(PO3)4 nanocrystalline luminescent thermometers.

关键词： Pr^3+ Temperature sensing luminescence intensity ratio Temperature sensitivity Grain size Dopant concentration

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Unexpected ecotone dynamics of a sand dune vegetation complex following water table decline

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Journal of Plant Ecology 2016年第1期9卷 40-50页

作者： Csaba Tölgyesi márta Zalatnai lászlóErdős Zoltán Bátori Nicole Rosemary Hupp lászlóKörmöczi Department of Ecology University of SzegedSzeged H-6726Hungary Wildlife Biology Program College of Forestry and ConservationUniversity of Montana32 Campus DriveMissoulaMontanaMT 59812USA

Aims Central Hungarian inland dune ranges harbor heterogeneous grassland vegetation with an extensive network of ecotones,arranged perpendicular to topography-driven hydrologic *** area suffers from severe aridification due to climate change and local anthropogenic factors,which have led to a dramatic decline of the water *** a result,groundwater is no longer reachable for lowlying plant communities;thus,we expect they are bound to undergo profound *** study investigates how the plant communities respond to this changing environment over time by monitoring ecotones,since they are frequently the hotspots of ecosystem *** monitored five ecotones along permanent belt transects for 15 years to characterize their dynamic response,and to identify the internal structural changes of the plant communities the ecotones *** Ecotones were delineated with the split moving window *** dynamics of two ecotone parameters,location and contrast,were analyzed with linear regression models incorporating two independent variables:study year as a measure of time since the loss of groundwater,and precipitation as a possible driver of interannual *** internal changes of the patches separated by the ecotones were analyzed using plant functional *** Findings Precipitation had no detectable effect on the ecotone descriptors,but study year influenced ecotones in an unusual *** position of the ecotones appeared to be very stable in time;their dynamics are stationary,not directional as we *** contrasts had clear tendencies;two ecotones disappeared,one new one was formed and two ecotones showed no *** internal changes of the patches over time were dramatic,showing a shift toward more xeric and more open plant assemblages in most stretches of the ***,the dynamic response of the vegetation was not patch expansion ***,but fusion ***,which profoundly restructured the vegetati

关键词： groundwater decline plant functional group sand dune vegetation split moving window stationary ecotone

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Scale effect of circularly polarized luminescent signal of matter

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National Science Review 2023年第5期10卷 232-239页

作者： Siyu Sun Xiaolin li Chen Xu Yan li YongZhen Wu Ben l.Feringa He Tian Xiang ma Key laboratory for Advanced materials and Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and Technology School of Physics East China University of Science and Technology Stratingh Institute for Chemistry and Zernike Institute for Advanced materials Faculty of Science and EngineeringUniversity of Groningen

Circularly polarized luminescence(CPl) is an important part in the research of modern luminescent materials and photoelectric ***,chiral molecules or chiral structures are the key factors to induce CPl spontaneous *** this study,a scale-effect model based on scalar theory was proposed to better understand the CPl signal of luminescent *** chiral structures being able to induce CPl,achiral ordered structures can also have a significant influence on CPl *** achiral structures are mainly reflected in the particle scale in micro-order or macro-order,*** CPl signal measured under most conditions depends on the scale of the ordered medium,and does not reflect the inherent chirality of the excited state of the luminescent *** kind of influence is difficult to be eliminated by simple and univers al strategies in *** the same time,it is found that the measurement entropy of CPl detection may be the key factor to determine the isotropy and anisotropy of the CPl *** discovery would bring new opportunities to the research of chiral luminescent *** strategy can also greatly reduce the development difficulty of CPl materials and show high application potential in biomedical,photoelectric information and other fields.

关键词： scale effect circularly polarized luminescent chirality quantum dots perovskite

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Spectrophotometric determination of tranexamic acid using vanillin

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药学学报 2009年第2期44卷 175-180页

作者： F.m.A. Rind m.G.H. laghari A.H. memon U.R. mughal E Almani N. memon m.Y. Khuhawar m.l. maheshwari Faculty of Pharmacy University of Sindh Jamshoro Pakistan Institute of Chemistry Faculty of Natural Sciences University of Sindh Jamshoro Pakistan

A new spectrophotometric method has been examined for the determination of the tranexamic acid (TA) by derivatization with vanillin (VAN). The molar absorptivity of TA was calculated 25 160 l·mol-1·cm-1 at λmax 354 nm and obeyed the Beer's law within 0.5-2.5 μg·ml-1. The color reaction was highly stable and did not show any change in absorbance up to 24 h. The method was applied for the analysis of TA from capsules, injections and tooth pastes. The amounts of TA found in capsules, injections and tooth pastes of various pharmaceutical companies were observed with 249.0-250.9 mg/capsule, 249.3-250.7 mg/injection and 0.048%-0.049% in tooth pastes with relative standard deviation (RSD) 0.2%-5.0% (n = 3).

关键词：分光方法氨甲环酸显色反应药物化学

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A Quantitative Analysis of mn Segregation at Partitioned Ferrite/Austenite Interface in a Fe-C-mn-Si Alloy

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Journal of materials Science & Technology 2009年第3期25卷 383-388页

作者： H. Guo S.W. Yang C.J.Shang X.m. Wang X.l. He Department of materials Physics and Chemistry University of Science and Technology Beijing Beijing 100083 China

mn segregation at austenite/ferrite interface is studied in a Fe-C-mn-Si alloy held at 656°C. mn is partitioned during the growth of ferrite and as a result, a mn pile-up exists in front of interface on the matrix side. An approach to evaluate mn segregation quantitatively is developed by combining STEm raster window scanning and simulation of the interaction of the electron beam with the sample to subtract the contribution of mn pile-up and obtain pure mn segregation value. The evaluated maximum mn interfacial segregation is in the order of a half-monolayer. Printed by Copyright ©.

关键词： Interfacial segregation Phase transformation STEm Beam broadening

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Nonlinear optical trapping effect with reverse saturable absorption

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Advanced Photonics 2023年第4期5卷 66-73页

作者： Zheng Zhu Yuquan Zhang Shuoshuo Zhang Aurele J.l.Adam Changjun min Hendrik Paul Urbach Xiaocong Yuan Shenzhen University Institute of Microscale Optoelectronics and State Key Laboratory of Radio Frequency Heterogeneous IntegrationNanophotonics Research CenterShenzhenChina Research Institute of Intelligent Sensing Research Center for Humanoid SensingZhejiang LabHangzhouChina Delft University of Technology Optics Research GroupDelftThe Netherlands

Nonlinear responses of nanoparticles induce enlightening phenomena in optical tweezers. With thegradual increase in optical intensity, effects from saturable absorption (SA) and reverse SA (RSA) arise insequence and thereby modulate the nonlinear properties of materials. In current nonlinear optical traps,however, the underlying physical mechanism is mainly confined within the SA regime because thresholdvalues required to excite the RSA regime are extremely high. Herein, we demonstrate, both in theory andexperiment, nonlinear optical tweezing within the RSA regime, proving that a fascinating composite trappingstate is achievable at ultrahigh intensities through an optical force reversal induced through nonlinearabsorption. Integrated results help in perfecting the nonlinear optical trapping system, thereby providingbeneficial guidance for wider applications of nonlinear optics.

关键词： nonlinear optical tweezers optical force reverse saturable absorption

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linewidth narrowing in free-space-running diamond Brillouin lasers

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High Power laser Science and Engineering 2023年第4期11卷 25-32页

作者： Duo Jin Zhenxu Bai Zhongan Zhao Yifu Chen Wenqiang Fan Yulei Wang Richard P.mildren Zhiwei lü Center for Advanced laser Technology Hebei University of TechnologyTianjinChina Hebei Key laboratory of Advanced laser Technology and Equipment TianjinChina mQ Photonics Research Centre Department of Physics and AstronomyMacquarie UniversitySydneyAustralia

This study analyzes the linewidth narrowing characteristics of free-space-running Brillouin lasers and investigates the approaches to achieve linewidth compression and power enhancement *** results show that the Stokes linewidth behavior in a free-space-running Brillouin laser cavity is determined by the phase diffusion of the pump and the technical noise of the ***,a Stokes light output with a power of 22.5 W and a linewidth of 3.2 kHz was obtained at a coupling mirror reflectivity of 96%,which is nearly 2.5 times compressed compared with the linewidth of the pump(7.36 kHz).In addition,the theorical analysis shows that at a pump power of 60Wand a coupling mirror reflectivity of 96%,a Stokes output with a linewidth of 1.6 kHz and up to 80%optical conversion efficiency can be achieved by reducing the insertion loss of the *** study provides a promising technical route to achieve high-power ultra-narrow linewidth special wavelength laser radiations.

关键词： high power narrow linewidth single-frequency laser stimulated Brillouin scattering

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保存最古老矿物结合多肽的中新世鸵鸟蛋壳化石首次组织化学研究

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古脊椎动物学报（中英文） 2024年第2期62卷 120-134页

作者：吴倩泮艳红李志恒周忠和艾莉达中国科学院大学北京100049 中国科学院古脊椎动物与古人类研究所中国科学院脊椎动物演化与人类起源重点实验室北京100044 南京大学地球科学与工程学院生物演化与环境科教融合中心关键地球物质循环前沿科学中心内生金属矿床成矿机制研究国家重点实验室南京210023

古蛋白质比古DNA具有更高的保存潜力,因此蛋白质组学研究可以帮助阐明一些超出古DNA研究领域的灭绝生物群体的生物学特征。迄今为止最古老的多肽发现于中国西北地区晚中新世临夏盆地的鸵鸟蛋壳化石中,是与蛋壳矿化相关的蛋白质struthioc... 详细信息

古蛋白质比古DNA具有更高的保存潜力,因此蛋白质组学研究可以帮助阐明一些超出古DNA研究领域的灭绝生物群体的生物学特征。迄今为止最古老的多肽发现于中国西北地区晚中新世临夏盆地的鸵鸟蛋壳化石中,是与蛋壳矿化相关的蛋白质struthiocalcin(SCA-1)的一部分。前人认为SCA-1在蛋壳中均匀分布,并因其与方解石晶体结合的特性而得以在地质历史中长时间保存。本次对同一鸵鸟蛋壳化石进行了组织学、扫描电子显微镜和拉曼光谱分析,发现蛋壳内侧锥体层的晶核含有部分磷灰石,其他部位则完全由方解石构成;这些晶核部分应当是在成岩作用过程中经历了磷酸盐化。在对该化石蛋壳样品脱钙处理后,其锥体层晶核部分存在残留物,呈现网络状纤维结构,其位置和形态与现生鸵鸟蛋壳中脱钙后残留的有机质相似。结果表明,该化石蛋壳中的古多肽可能集中保存在锥体层晶核处,而非在整个蛋壳中均匀分布。磷酸盐化可能是另一个有利于有机物长期保存的埋藏过程。临夏盆地的古气候和埋藏环境可能为该古蛋白分子的保存提供了有利的条件。建议在未来研究中进行更深入的组织化学和矿物学分析,以进一步了解该盆地有机质和古蛋白的保存机制。

关键词：化石有机质生物矿化蛋白磷灰石磷酸盐化鸵鸟蛋壳古蛋白

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Structure,microstructure,dielectric and piezoelectric properties of(1−x-y)BiFeO_(3)-xPbFe_(0.5)Nb_(0.5)O_(3)-yPbTiO_(3)ceramics

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Journal of Advanced Dielectrics 2022年第1期12卷 45-52页

作者： E.I.Sitalo N.A.Boldyrev l.A.Shilkina A.V.Nazarenko A.V.Nagaenko l.A.Reznichenko Research Institute of Physics Southern Federal University No 194 Stachki Ave.Rostov-on-Don 344090Russia Southern Scientific Center of RAS No.41 Chekhov Ave. Rostov-on-Don 344006Russia Institute of High Technology and Piezo Technic Southern Federal UniversityNo 10 Milchakov St.Rostov-on-Don 344090Russia

Ceramics of quasi-binary concentration section(x=0.50,0.1≤y≤0.2,Δy=0.025)of the ternary solid solution system(1−x−y)BiFeO_(3)-xPbFe_(0.5)Nb_(0.5)O_(3)-yPbTiO_(3)were prepared by the conventional solid-phase reaction *** using X-ray diffraction technique,the phase diagram of the system was constructed,which was shown to contain the regions of cubic and tetragonal symmetry and the morphotropic phase boundary between *** morphology,dielectric and piezoelectric properties of the selected solid solutions were *** highest piezoelectric coefficient d_(33)=260 pC/N was *** characteristics of ceramics revealed ferroelectric relaxor behavior,a region of diffuse phase transition from the paraelectric to ferroelectric phase in the temperature range of 350-500 K.

关键词： Dielectric properties perovskites multiferroics piezoelectric properties solid solutions

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Performance Evaluation of Calcium Alkali-treated Oil Palm/Pineapple Fibre/Bio-phenolic Composites

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Journal of Bionic Engineering 2022年第5期19卷 1493-1503页

作者： Sameer A.Awad Hassan Fouad Eman m.Khalaf N.Saba Hom N.Dhakal m.Jawaid Othman Y.Alothman Department of Chemistry School of Science and TechnologyUniversity of New EnglandArmidaleNSW 2351Australia Department of Chemistry College of Education for Pure ScienceUniversity of Al-AnbarRamadi 31001Iraq Biomedical Engineering Department Faculty of EngineeringHelwan UniversityHelwan 11792Egypt Pharmacy Department Al-Maarif University CollegeAnbar 3001 RamadiIraq laboratory of Biocomposite Technology Institute of Tropical Forestry and Forest Products(INTROP)Universiti Putra Malaysia43400 SerdangMalaysia Advanced Polymers and Composites(APC)Research Group School of Mechanical and Design EngineeringUniversity of PortsmouthPortsmouth PO13DJUK Department of Chemical Engineering College of EngineeringKing Saud UniversityRiyadh 11433Saudi Arabia

The utilisation of oil palm fibre(OPF)and pineapple leaf fibres(PAlF)as reinforcement materials for bio-phenolic composites is growing especially in automotive lightweight *** major aim of this current study is to investigate the influence of alkali(Ca(OH)_(2)) treatment on pure and hybrid *** effects of enhancements in chemical interactions were evaluated by the Fourier-Transform Infrared Spectrometer(FTIR).Dynamic mechanical Analysis(DmA)and Thermogravimetric Analysis(TGA)performance of untreated reinforcements(OPF and PAlF)and treated(OPF/OPF)composites at varying temperature and noted sufficient interfacial bonding contributing towards the improvements in thermal *** DmA results,the storage modulus improved with treated composites while the damping factor was ***,the treated hybrid composites exhibited significant improvements in thermal stability compared to untreated fibre *** results indicated that alkali calcium hydroxide(Ca(OH2(:T)incorporation in hybrid composites(OPF/PAlF)results in increased tensile strength and modulus among all ***,the alkali-treated(Ca(OH)_(2))-treated pure composite(T/50%PAlF),and hybrid composites(T/1OPF.1PAlF)exhibited better flexural strength as compared with other *** contrast,the T/50%PAlF showed higher flexural stress of 78.2 mPa,while the flexural modulus was recorded at 6503 *** can be proposed from the findings of this study that the alkali treatment(5%Ca(OH)_(2))can be utilised to improve the strength and efficiency of agriculture biomass to be used as reinforcements in ***,the hybridisation of bio-fibre composites has the potential as a novel variety of biodegradable and sustainable composites appropriate for several industrial and engineering applications.

关键词： Hybrid fibre composites Alkali treatments Surface modifications mechanical properties Thermal stability

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