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具有BCC或FCC晶体结构的固溶体高熵合金设计

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材料工程 2024年第1期52卷 16-26页

作者： HORBAN v.F. 乌克兰国家科学院弗兰采维奇材料问题研究所乌克兰基辅03680

高熵合金最初报道于21世纪初期,该类合金具有较高的混合熵值,使其具有优异的热稳定性;较大的晶格畸变,产生了强烈固溶强化效果;较大的负焓值导致在晶粒内部形成团簇结构,有效阻碍了位错运动,进一步提高了合金强度。高熵合金独有的这些特... 详细信息

高熵合金最初报道于21世纪初期,该类合金具有较高的混合熵值,使其具有优异的热稳定性;较大的晶格畸变,产生了强烈固溶强化效果;较大的负焓值导致在晶粒内部形成团簇结构,有效阻碍了位错运动,进一步提高了合金强度。高熵合金独有的这些特性,使其在低温和高温条件下均有望表现出优异的物理性能和力学性能,引起了广泛的关注,研究报道呈爆发性增长。本文根据已有的BCC和FCC结构高熵合金物理-力学性能数据,分析了电子浓度、晶格常数、原子错配度、混合焓、硬度、弹性模量和归一化硬度等参数之间的关系,提出了BCC和FCC晶体结构的高熵合金弹性模量和硬度的经验计算公式,在此基础之上,综合考虑合金密度、塑性和服役工况等条件,提出了BCC和FCC结构的高熵合金成分设计方法。最后指出高熵合金的持久性能、大尺寸铸锭的成分和性能均匀性以及大尺寸合金锭的制备是高熵合金工程应用需解决的关键问题。

关键词：高熵合金电子浓度晶格常数晶格畸变混合焓硬度弹性模量归一化硬度

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Tax enforcement activities:Evidence on the impact of a threat-of-audit letter

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Economic and Political Studies 2024年第2期12卷 188-206页

作者： Carlo v.Fiorio Alessandro Santoro Department of Economics Management and Quantitative Methods(DEMM)University of MilanMilanItaly The Research Institute for the Evaluation of Public Policies Bruno Kessler Foundation(FBK-IRVAPP)TrentoItaly Dondena Centre MilanItaly Department of Economics Management and Statistics(DEMS)University of Milan-BicoccaMilanItaly Centre for European Studies(CefES) University of Milan-BicoccaMilanItaly

As part of their ordinary enforcement activities,tax authorities around the world use letters and other forms of personalised communications to elicit tax compliance at a low *** literature shows that the impact of a threat-of-audit letter(TAL)depends critically on the credibility of the letter which,in turn,depends on the information disclosed to the *** study a TAL that is credible because it also uses third-party information to target a form of cost manipulation but,at the same time,incentivises alternative forms of cost manipulation by not targeting *** find that the direct impact on the targeted cost manipulation is stronger than the strategic increase in other costs,and therefore the overall effect of the TAL on taxable income is *** approach can be applied to any letter or enforcement action that reveals information to taxpayers and thus prompts their strategic *** observing the taxpayers’responses along all relevant dimensions,the tax authority can evaluate the impact of the strategy and also obtain valuable information to target future enforcement activities.

关键词： Tax compliance by businesses threat-of-audit letter difference-indifferences small business taxation

First results of turbulence investigation on Globus-M2 using radial correlation Doppler reflectometry

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Plasma Science and Technology 2024年第10期26卷 49-55页

作者： A.PONOMARENKO A.YASHIN v.GUSEv E.KISELEv G.KURSKIEv v.MINAEv Y.PETROv N.SAKHAROv P.SHCHEGOLEv E.TKACHENKO N.ZHILTSOv Peter the Great St.Petersburg Polytechnic University St.Petersburg 195251Russia Ioffe Institute St.Petersburg 194064Russia

The first results of investigation of the turbulence structure using Doppler backscattering(DBS)on the Globus-M2 tokamak are presented.A one-channel DBS system with a variable probing frequency within the 18–26 GHz range was installed to investigate the edge plasma at normalized minor radiiρ=0.9–*** correlation Doppler reflectometry was used to study the changes in turbulence eddies after the LH *** analysis was applied to the phase derivative of complex in-phase and quadrature(IQ)signals of the DBS diagnostic as it contains information about the poloidal plasma rotation *** L-mode,the radial correlation length L_(r)is estimated to be 3 cm and after transition to H-mode reduces to approximately 2 *** modelling in a linear local approximation using code GENE indicates that the instability with positive growth rate at the normalized minor radiusρ=0.75 in L-mode and H-mode on Globus-M2 was the ion temperature gradient(ITG)mode.

关键词： tokamak turbulence Doppler backscattering correlation reflectometry

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Accounting for Quadratic and Cubic Invariants in Continuum Mechanics–An Overview

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Fluid Dynamics & Materials Processing 2024年第9期20卷 1925-1939页

作者： Artur v.Dmitrenko vladislav M.Ovsyannikov Department of Physics National Research Nuclear University(MEPhI)Kashirskoye Shosse 31Moscow115409Russian Federation Department of Thermal Engineering and Department of Waterways Ports and Hydraulic StructuresRussian University of Transport(MIIT)Obraztsova Street 9Moscow127994Russian Federation

The differential equations of continuum mechanics are the basis of an uncountable variety of phenomena and technological processes in fluid-dynamics and related *** equations contain derivatives of the first order with respect to *** derivation of the equations of continuum mechanics uses the limit transitions of the tendency of the volume increment and the time increment to *** are used to derive the wave *** differential wave equation is second order in ***,increments of volume and increments of time in continuum mechanics should be considered as small but finite quantities for problems of wave *** is important for calculating the generation of sound waves and water hammer ***,the Euler continuity equation with finite time increments is of *** finiteness of the time increment makes it possible to take into account the quadratic and cubic invariants of the strain rate *** is a new branch in *** and cubic invariants will be used in differential wave equations of the second and third order in time.

关键词： Quadratic invariant cubic invariant continuity equation generation of periodic waves N.E.Zhukovsky’s hydraulic shock turbulence

Unveiling ferroptosis as a promising therapeutic avenue for colorectal cancer and colitis treatment

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Acta Pharmaceutica Sinica B 2024年第9期14卷 3785-3801页

作者： Aaron T.Kaoy Christian v.Cabanlongy Kendra Padilla Xiang Xue Department of Biochemistry and Molecular Biology University of New MexicoAlbuquerqueNM 87131USA

Ferroptosis is a novel type of regulated cell death(RCD)involving iron accumulation and lipid *** its discovery in 2012,various studies have shown that ferroptosis is associated with the pathogenesis of various *** cell death has also been linked to intestinal dysfunction but can act as either a positive or negative regulator of intestinal disease,depending on the cell type and disease *** continued investigation of mechanisms underlying ferroptosis provides a wealth of potential for developing novel *** the growing prevalence of intestinal diseases,particularly colorectal cancer(CRC)and inflammatory bowel disease(IBD),this review article focuses on potential therapeutics targeting the ferroptotic pathway in relation to CRC and IBD.

关键词： Ferroptosis Colorectal cancer Inflammatory bowel disease Cell death Molecular mechanisms Iron metabolism Drug therapies Targeted therapeutics

Advances in two-dimensional molybdenum ditelluride(MoTe2):A comprehensive review of properties,preparation methods,and applications

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SusMat 2024年第5期4卷 31-69页

作者： Pratik v.Shinde Muzammil Hussain Elisa Moretti Alberto vomiero Department of Molecular Sciences and Nanosystems Ca’Foscari University of VeniceVeneziaItaly Department of Industrial Engineering University of PadovaPadovaItaly Department of Engineering Sciences and Mathematics Lulea University of TechnologyLuleaSweden

In the past decade,molybdenum ditelluride(MoTe2)has received significant attention from the scientific community due to its structural features and unique properties originate from *** the current review,the properties,various preparation approaches,and versatile applications of MoTe2 are *** review provides a brief update on the state of our fundamental understanding of MoTe2 material and also discusses the issues that need to be *** introduce MoTe2,we briefly summarize its structural,optoelectronic,magnetic,and mechanical properties in the ***,different preparation meth-ods of MoTe2,such as exfoliation,laser treatment,deposition,hydrothermal,microwave,and molecular beam epitaxy,are *** excellent electri-cal conductivity,strong optical activity,tunable bandgap,high sensitivity,and impressive stability make it an ideal contender for different applications,includ-ing energy storage,catalysis,sensors,solar cells,photodetectors,and *** performance of MoTe2 in these applications is systematically introduced along with mechanistic *** the end of the article,the challenges and possible future directions are highlighted to further modify MoTe2 material for the numerous ***,the availability of different phases and layer structures implies a potential for MoTe2 to lead an era of two-dimensional materials that began from the exfoliation of graphene.

关键词： 2D materials MoTe2 (opto)electronic devices phase structure and bandgap tuning

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

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Myelin histology:a key tool in nervous system research

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Neural Regeneration Research 2024年第2期19卷 277-281页

作者： Óscar Darío García-García víctor Carriel Jesús Chato-Astrain Department of Histology Tissue Engineering GroupUniversity of Granada&Instituto de Investigación Biosanitaria ibs.GRANADAGranadaSpain

The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve *** to the complex structure and composition of myelin,various histological techniques have been developed over the centuries to evaluate myelin under normal,pathological or experimental ***,methods to assess myelin integrity or content are key tools in both clinical diagnosis and neuroscience *** this review,we provide an updated summary of the composition and structure of the myelin sheath and discuss some histological procedures,from tissue fixation and processing techniques to the most used and practical myelin histological staining *** the lipoprotein nature of myelin,the main features and technical details of the different available methods that can be used to evaluate the lipid or protein components of myelin are described,as well as the precise ultrastructural techniques.

关键词： fluorescence microscopy histology light microscopy lipid histochemistry metallographic techniques myelin histochemistry myelin immunohistochemistry myelin structure&composition myelin ultrastructural evaluation tissue fixation&processing

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Quality of drinking water and risk to the health of the population of the south Baikal region (Russia)

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Emerging Contaminants 2024年第2期10卷 106-114页

作者： viktor S.Rukavishnikov Natalia v.Efimova Mikhail F.Savchenkov Inna v.Mylnikova Alexander A.Lisovtsov East-Siberian Institute of Medical and Ecological Research 665827AngarskRussia

Providing good quality water in sufficient quantities is a major challenge in the *** purpose of the study is to assess the quality of drinking water and the health risk of various population groups in the southern Baikal region(Siberia,Russia)under changing hydrological *** Baikal is the largest freshwater body of water and is one of the sites protected by *** and *** analysis of centralized and non-centralized water supply was carried out in the south-eastern part of the Irkutsk region,adjacent to Lake *** data used are from the Baikal(regional)Information Center for 2011–2022,and they include the results of monitoring the water quality of the centralized domestic and drinking water supply(CDW)with 140 thousand samples,and non-centralized domestic and drinking water supply(NDW)with 108 thousand *** all samples,17 substances were *** addition,during the flood period,accompanied by additional water disinfection,trihalomethanes were determined in populated areas exposed to negative *** quality of drinking water was assessed in comparison with the maximum permissible concentrations of substances(MPCs)approved by regulatory documents of *** assessment of the characteristics of drinking water consumption by the population of the Baikal region was carried out,based on interview data from sample groups of the *** assessment of the risk to public health,due to chronic oral intake of chemicals,was carried out using the values of the hazard coefficient(HQi),the hazard index(HI),individual carcinogenic risk(ICR),and population carcinogenic risk(PCR).village residents more often use underground water sources(centralized and non-centralized).Residents of cities are provided with water from surface sources(Lake Baikal and the Angara River).Significant concentrations of iron,nitrates,and manganese were found in drinking water used by *** concentrations of iron-2.25 mg/dl,manganese

关键词： Drinking water Noncarcinogenic risk Carcinogenic risk Population South Baikal region