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Structural and chemical transformations of CuZn alloy nanoparticles under reactive redox atmospheres:An in situ TEM study

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Nano Research 2024年第7期17卷 6265-6273页

作者： Shengnan Yue Qian Li Chaobin Zeng alexander Klyushin Ramzi Farra Marc-Georg Willinger Xing Huang College of Chemistry Fuzhou UniversityFuzhou 350108China Qingyuan Innovation Laboratory Quanzhou 362801China Hitachi High-Tech Scientific Solutions(Beijing)Co. Ltd.Beijing 100015China MAX IV Laboratory Lund UniversityBox 11822100 LundSweden Department of Inorganic Chemistry Fritz-Haber Institute of Max Planck SocietyBerlin 14195Germany Department of Chemistry Technical University of MunichGarching 85748Germany

Alloying metals to form intermetallics has been proven effective in tuning the chemical properties of metal-based ***,intermetallic alloys can undergo structural and chemical transformations under reactive conditions,leading to changes in their catalytic *** and understanding these transformations are crucial for establishing relevant structureperformance relationships and for the rational design of alloy-based *** this work,we used CuZn alloy nanoparticles(NPs)as a model material system and employed in situ transmission electron microscopy(TEM)to investigate the structural and chemical changes of CuZn NPs under H_(2),O_(2)and their *** results show how CuZn NPs undergo sequential transformations in the gas mixture at elevated temperatures,starting with gradual leaching and segregation of Zn,followed by oxidation at the NP *** remaining copper at the core of particles can then engage in dynamic behavior,eventually freeing itself from the zinc oxide *** structural dynamics arises from an oscillatory phase transition between Cu and Cu_(2)O and is correlated with the catalytic water formation,as confirmed by in situ mass spectrometry(MS).Under pure H_(2)or O_(2)atmosphere,we observe different structural evolution pathways and final chemical states of CuZn NPs compared to those in the gas *** results clearly demonstrate that the chemical state of alloy NPs can vary considerably under reactive redox atmospheres,particularly for those containing elements with distinct redox properties,necessitating the use of in situ or detailed ex situ characterizations to gain relevant insights into the states of intermetallic alloy-based catalysts and structure-activity relationships.

关键词： In situ transmission electron microscopy(TEM) CuZn alloy structural and chemical transformations redox atmosphere

Photonic properties and applications of multi-functional organo-lanthanide complexes:Recent advances

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Journal of Rare Earths 2024年第1期42卷 16-27,I0001页

作者： Virender Archana Chauhan Ashwani Kumar Gurjaspreet Singh alexander A.Solovev Jichuan Xiong Xuefeng Liu Brij Mohan Department of Chemistry Kurukshetra University KurukshetraKurukshetra136119India Aggarwal College Ballabhgarh121004Department of Higher EducationHaryanaIndia Department of Chemistry&Centre for Advanced Studies in Chemistry Panjab UniversityChandigarh160014India Department of Materials Science Fudan UniversityShanghai200433China School of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjing210094China College of Ocean Food and Biological Engineering Jimei UniversityXiamen361021China

Lanthanides(Ln(Ⅲ))based compounds as light-emitting materials have emerged as successful agents in high-performance defense and lighting systems,magnets,bio-markers,and ***,they have recently gained much attention as energy-saving and cost-effective luminescent materials and their applications in analyte *** present review summarizes powerful features and recent developments of organo-lanthanide complexes in lighting applications with a particular focus on visible light emitters,including Eu(Ⅲ),Tb(Ⅲ),Sm(Ⅲ),and Dy(Ⅲ)*** addition,this review discusses the most relevant aspects of photosensitization,such as the structure,property,functionalization of primary and secondary ligands,and molecular *** addition,coordination sites of organo-lanthanide complexes and their applications collectively contribute to the improved performance of innovative luminescent ***,the current challenges and key recommendations for advancing organolanthanides in material science are provided.

关键词： Lanthanides Organometallic Luminescent Lifetime OLED Rare earths

Impact of doping profiles on the formation of laser-active centers in bismuth-doped GeO_(2)–SiO_(2)glass fibers

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Photonics Research 2024年第2期12卷 260-270页

作者： SERGEY ALYSHEV alexander VAKHRUSHEV ALEKSANDR KHEGAI ELENA FIRSTOVA KONSTANTIN RIUMKIN MIKHAIL MELKUMOV LYUDMILA ISKHAKOVA ANDREY UMNIKOV SERGEI FIRSTOV Prokhorov General Physics Institute of the Russian Academy of Sciences Dianov Fiber Optics Research Center119333 MoscowRussia Devyatykh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences 603951 Nizhny NovgorodRussia

Multi-wavelength-band transmission technology based on the exploitation of the extended spectral region is considered as a potential approach to increase the transmission capacity in the deployed fiber-optic communication *** development of optical amplifiers operating in the O-,E-,S-,and U-telecom bands is an extremely important challenge for the successful implementation of this ***-doped fibers are of increasing interest as gain materials,which can be used to provide broadband amplification in the mentioned telecom *** is due to the ability of Bi ions incorporated into glass network to form bismuth active centers(BACs)with specific optical properties,which are primarily determined by the glass *** this work,the impact of the doping profiles of both Ge atoms as glass modifiers and Bi ions on the BACs formation is studied using a series of bismuth-doped fibers fabricated by the modified chemical vapor deposition(MCVD)*** Bi-to-BACs conversion efficiency in various spatial regions of the studied samples is *** is turned out that for high-Bi concentration regions,the conversion efficiency is very low(less than 10%).In addition,the relationship of the conversion efficiency to the distribution of Bi ions and/or Ge atoms is ***,a continuous-wave laser at 1.46μm with a record slope efficiency of 80%is demonstrated using a Bi-doped fiber with confined doping profile,where the Bi-to-BACs conversion efficiency is 35%.This paper provides new information which might help to facilitate understanding of the features of Bi-doped fibers and their potentially achievable characteristics.

关键词： fiber fibers bismuth

High-speed performance self-powered short wave ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3)

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Journal of Semiconductors 2024年第4期45卷 56-62页

作者： Aleksei Almaev alexander Tsymbalov Bogdan Kushnarev Vladimir Nikolaev Alexei Pechnikov Mikhail Scheglov Andrei Chikiryaka Petr Korusenko Research and Development Center for Advanced Technologies in Microelectronics National Research Tomsk State UniversityTomsk 634050Russia Fokon LLC Kaluga 248035Russia Department of Semiconductor Electronics and Physics of Semiconductors National University of Science and Technology MISISMoscow 119049Russia Perfect Crystals LLC Saint Petersburg 194223Russia Department of Solid-State Electronics Saint Petersburg State UniversitySaint Petersburg 199034Russia Department of Physics Omsk State Technical UniversityOmsk 644050Russia

High-speed solar-blind short wavelength ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3)layers with Pt contacts were demonstrated and their properties were studied in ***κ(ε)-Ga_(2)O_(3)layers were deposited by the halide vapor phase epitaxy on patterned GaN templates with sapphire *** spectral dependencies of the photoelectric properties of struc-tures were analyzed in the wavelength interval 200-370 *** maximum photo to dark current ratio,responsivity,detectiv-ity and external quantum efficiency of structures were determined as:180.86 ***.,3.57 A/W,1.78×10^(12) Hz^(0.5)∙cm·W^(-1) and 2193.6%,respectively,at a wavelength of 200 nm and an applied voltage of 1 *** enhancement of the photoresponse was caused by the decrease in the Schottky barrier at the Pt/κ(ε)-Ga_(2)O_(3)interface under ultraviolet *** detectors demon-strated could functionalize in self-powered mode due to built-in electric field at the Pt/κ(ε)-Ga_(2)O_(3)*** responsivity and external quantum efficiency of the structures at a wavelength of 254 nm and zero applied voltage were 0.9 mA/W and 0.46%,*** rise and decay times in self-powered mode did not exceed 100 ms.

关键词： κ(ε)-gallium oxide solar-blind shortwave ultraviolet radiation detectors self-powered operation mode

Convergent Data-Driven Regularizations for CT Reconstruction

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1342-1368页

作者： Samira Kabri alexander Auras Danilo Riccio Harmut Bauermeister Martin Benning Michael Moeller Martin Burger Helmholtz Imaging Deutsches Elektronen-Synchrotron DESYNotkestr.8522607 HamburgGermany Institute for Vision and Graphics University of SiegenAdolf-Reichwein-StraBe 2a57076 SiegenGermany School of Mathematical Sciences Queen Mary University of LondonMile End RoadLondon E14NSUK The Alan Turing Institute British Library96 Euston RdLondon NW12DBUK Fachbereich Mathematik Universitat HamburgBundesstrasse 5520146 HamburgGermany

The reconstruction of images from their corresponding noisy Radon transform is a typical example of an ill-posed linear inverse problem as arising in the application of computerized tomography(CT).As the(naive)solution does not depend on the measured data continuously,regularization is needed to reestablish a continuous *** this work,we investigate simple,but yet still provably convergent approaches to learning linear regularization methods from *** specifically,we analyze two approaches:one generic linear regularization that learns how to manipulate the singular values of the linear operator in an extension of our previous work,and one tailored approach in the Fourier domain that is specific to *** prove that such approaches become convergent regularization methods as well as the fact that the reconstructions they provide are typically much smoother than the training data they were trained ***,we compare the spectral as well as the Fourier-based approaches for CT-reconstruction numerically,discuss their advantages and disadvantages and investigate the effect of discretization errors at differentresolutions.

关键词： Inverse problems Regularization Computerized tomography(CT) Machine learning

Parallelizable Calculation of Observables Values on Analog Quantum Computer

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Journal of Applied Mathematics and Physics 2024年第7期12卷 2400-2406页

作者： alexander Soiguine SOiGUINE Quantum Computing Aliso Viejo USA

The superiority of hypothetical quantum computers is not due to faster calculations but due to different schemes of calculations running on special hardware. The core of quantum computing follows the way a state of a quantum system is defined when basic things interact with each other. In conventional approach it is implemented through tensor product of qubits. In the geometric algebra formalism simultaneous availability of all the results for non-measured observables is based on the definition of states as points on three-dimensional sphere.

关键词： Geometric Algebra Wave Functions Entanglement Maxwell Equations Three-Dimensional Sphere States Observables Measurements GPU Multithreading OpenCL

A new look at the first dinosaur discovered in Antarctica:reappraisal of Antarctopelta oliveroi(Ankylosauria:Parankylosauria)

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Advances in Polar Science 2024年第1期35卷 78-107页

作者： Sergio SOTO ACUÑA alexander OVARGAS Jonatan KALUZA Red Paleontológica U-Chile Departamento de BiologíaFacultad de CienciasUniversidad de ChileÑuñoa 7800003Chile Escuela de Geología Facultad de CienciasIngeniería y TecnologíaUniversidad MayorProvidenciaSantiago 7500994Chile Fundación de Historia Natural Félix de Azara Universidad MaimónidesBuenos Aires C1405Argentina Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Buenos Aires C1425FQBArgentina

The first dinosaur discovered in the Antarctic continent was the ankylosaur Antarctopelta oliveroi in the ***,since then several hypotheses of phylogenetical relationships have been proposed because these have been depended on how the skeletal remains have been *** main obstacle for clarifying its phylogenetic position is that many portions of the skeleton remain unknown,in addition to the presence of unknown characters in typical *** an ankylosaurid,nodosaurid,or even a chimaera,a recent proposal based on mostly complete material of a new ankylosaur from Chilean Patagonia provided support for a novel phylogenetic hypothesis:Antarctopelta and other southern ankylosaurs are an early branching clade,the Parankylosauria,whose origin probably dates to the Late *** the light of this new view,a redescription of the available skeletal remains is provided together with a new reconstruction of the first Antarctic dinosaur known to the science community.

关键词： Antarctic Peninsula Biogeographic Weddellian Province Parankylosauria Antarctopelta

Quantum Computingvia Entanglement in Geometric Algebra Approach

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Journal of Applied Mathematics and Physics 2024年第2期12卷 445-457页

作者： alexander Soiguine SOiGUINE Quantum Computing Aliso Viejo USA

The superiority of hypothetical quantum computers is not due to faster calculations but due to different scheme of calculations running on special hardware. At the same time, one should realize that quantum computers would only provide dramatic speedups for a few specific problems, for example, factoring integers and breaking cryptographic codes in the conventional quantum computing approach. The core of quantum computing follows the way a state of a quantum system is defined when basic things interact with each other. In the conventional approach, it is implemented through the tensor product of qubits. In the suggested geometric algebra formalism simultaneous availability of all the results for non-measured observables is based on the definition of states as points on a three-dimensional sphere, which is very different from the usual Hilbert space scheme.

关键词： Geometric Algebra Wave Functions Entanglement Maxwell Equations Three-Dimensional Sphere

Parasites of the liver:A global problem?

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World Journal of Gastroenterology 2024年第30期30卷 3554-3559页

作者： Vladislav V Tsukanov alexander V Vasyutin Julia L Tonkikh Clinical Department of the Digestive System Pathology of Adults and Children Federal Research Center“Krasnoyarsk Science Center”of the Siberian Branch of the Russian Academy of SciencesScientific Research Institute of Medical Problems of the NorthKrasnoyarsk 660022Russia

Parasitic liver diseases can be caused by trematodes,cestodes,nematodes,and *** pathology is significant because millions of people in different parts of the world have liver parasites,which can manifest themselves in the development of inflammation,liver cysts,cholecystitis,cholelithiasis,pancreatitis and liver cirrhosis that are often threatening their *** International Agency for Research on Cancer considers three species of trematodes,Schistosoma haematobium,Opisthorchis viverrini and Clonorchis sinensis,to be *** modern examination methods,in some cases including extensive screening of large populations,are required for diagnosing liver *** of parasitic liver diseases is differentiated and can involve a combination of surgical and therapeutic *** is no doubt that the clinical and epidemiological scale allows one to regard parasitic liver diseases as a global healthcare problem.

关键词： Liver Parasites Epidemiology Diagnosis Clinics Treatment Echinococcosis Opisthorchiasis Fascioliasis Schistosomiasis