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Journal of Rare Earths 2019年第11期37卷 1152-1156页

作者： Marcin Runowski inocencio R.Martin Vladimir N.Sigaev vitaliy i.savinkov Georgiy Yu.Shakhgildyan Stefan Lis Faculty of Chemistry Adam Mickiewicz UniversityUniwersytetu Poznanskiego 861-614 PoznanPoland Departamento de Fisica Instituto de Materiales y Nanotecnologia(IMN)Universidad de La LagunaApdo.456E-38200 San Cristobal de La LagunaSanta Cruz de TenerifeSpain D.Mendeleev University of Chemical Technology Miusskaya Sq.9125047 MoscowRussia

Multifunctional core/shell type,luminescent-plasmonic material composed of lanthanide doped microspheres(≈50μm)and gold nanoparticles(Au NPs;≈10-20 nm)deposited onto their surface,were successfully prepared(Nd^3+:YAS@Au).The material was synthesized to combine the luminescence properties of the Nd^3+-doped microspheres,*** resonance with plasmonic activity of the surface Au NPs,*** enhanced Raman scattering(SERS)effect,within a single,micro-sized *** luminescent-plasmonic microspheres were used as the active SERS substrate for detection of the organic probe,and for generation of Whispering Gallery Modes(WGM),which red-shift together with increasing laser power(temperature elevation).The products obtained were analysed with optical,scanning and transmission electron microscopy(SEM and TEM),as well as by Raman,absorption and photoluminescence spectroscopies.

关键词： Luminescence Gold NPs-SPR Surface enhanced Raman scattering Microsphere resonators-WGM Lanthanide ions Optical sensors

光催化二氧化碳还原制多碳产物的先进光催化剂设计与机制:现状与挑战

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Chinese Journal of Catalysis 2024年第5期60卷 25-41页

作者：杜晨宇盛剑平钟丰忆何烨 vitaliy P.Guro 孙艳娟董帆电子科技大学资源与环境学院四川成都611731 中国气象局气候资源经济转化重点开放实验室重庆401147 电子科技大学基础与前沿研究院碳中和与环境能源技术研究中心四川成都611731 乌兹别克斯坦共和国科学院通用和无机化学研究所乌兹别克斯坦什干100047

在可持续碳资源利用的研究中,光催化CO_(2)转化为高附加值化学品的前景日益凸显.相较于常见的CO_(2)还原产物如甲烷、一氧化碳或甲酸,具有两个或更多碳原子的C_(2+)化合物因其具有更高的附加值而备受关注.然而,目前的研究面临着C–C偶... 详细信息

在可持续碳资源利用的研究中,光催化CO_(2)转化为高附加值化学品的前景日益凸显.相较于常见的CO_(2)还原产物如甲烷、一氧化碳或甲酸,具有两个或更多碳原子的C_(2+)化合物因其具有更高的附加值而备受关注.然而,目前的研究面临着C–C偶联过程和多质子耦合电子转移效率的限制,导致光催化CO_(2)的还原反应产物主要为C1化合物.常规光催化剂难以突破这些动力学和热力学壁垒,导致目标产物C_(2+)化合物的生成量远低于实际工业应用所需要的水平.因此,开发具有良好性能的光催化剂,以实现C_(2+)化合物的高效制备,仍是当前面临的重要科学挑战.本文系统性地概述了光催化CO_(2)还原为C_(2+)化合物领域的最新研究进展.首先,从光催化的基本原理及C_(2+)产物的生成路径出发,在光催化剂设计方面,为突破C–C偶联和多质子耦合电子转移的限制,需要解决以下问题:(1)关键中间产物的生成与吸附转移;(2)活性位点对于中间产物的选择性;(3)光生电子的寿命与定向转移.随后,详细介绍了高效、高选择性光催化剂的合理设计策略,包括缺陷工程、双金属位点、表面等离子体共振以及异质结构造等.同时,深入探讨了C–C偶联和多电子偶联的质子转移过程的催化机制.最后,展望了光催化CO_(2)还原制C_(2+)高附加值产物的未来研究方向,催化剂设计与机制研究的关键方向包括:(1)设计高选择性和高效吸附*CO中间体的活性位点,以提升催化性能;(2)设计具有轨道匹配的双活性位点以减少邻近*CO中间体间的静电排斥,促进C–C耦合;(3)从分子轨道相互作用角度深入理解C–C耦合和电子转移过程,揭示反应机制;(4)鉴别反应过程中的自由基组分,阐明多质子耦合电子转移过程的机理.综上所述,本文系统地梳理了光催化CO_(2)还原制C_(2+)高附加值产物的研究进展、关键问题、催化剂设计原理以及未来研究方向,旨在为开发设计高效、高选择性催化剂提供有益的参考.

关键词： CO_(2)还原 C_(2+)产物光催化活性位反应机理

Newly identified Au-Ag-Bi-Te mineralization in the Aydindere skarn Fe and Cu deposit， Giresun， NE Turkey: implications of gold mineralization during retrograde skarn evolution

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Journal of Earth Science 2024年

作者： Ahmet Sasmaz vitaliy Sukach Serhiy Bondarenko Hryhorii Aleksiienko Hengameh Erfanian Kaseb Bilge Sasmaz Sergiy Kurylo Oleksandr Hrinchenko Volodymyr Somka Panagiotis Voudouris Department of Geology， Firat University Faculty of Geology and Geoenvironment， National and Kapodistrian University of Athens Mineralogy and Ore Formation of National Academy of Science， M.P.Semenenko institute of Geochemistry 3. Department of Petroleum Engineering， Eqbal Lahoori institute of Higher Education

This study investigates the mineralogy and mineral-chemistry of a newly discovered Au-Ag-Bi-Te mineralization at the Aydindere Fe-Cu skarn deposit， within the Pontides Tectonic Unit， northeastern Turkey. The mineralization is developed in the skarn zone at the contact between Upper Cretaceous andesite-pyroclastic rocks and a Paleocene-Eocene i-type granitoid. The principal ore minerals of the Aydindere Fe-Cu deposit are oxides (magnetite)， sulfides (pyrite-chalcopyrite-galena-sphalerite)， tellurides/sulfotellurides (tetradymite， hessite)， sulfosalts (wittichenite， emplectite， aikinite) and native gold-electrum. Skarn minerals include anhydrous phases (garnet) formed in a prograde stage and hydrous phases (amphibole， epidote， chlorite)， which were formed in a retrograde stage in association with quartz， adularia， apatite and late calcite. Sulfides， tellurides and sulfosalts are introduced during the retrograde stage. The Au-Ag-Bi-Te mineralization was detected for the first time within the western ore body of the Aydindere deposit， and occurs in calcite-bearing sulfide bodies that cut magnetite-garnet-amphibole-epidote skarns with magnetite ores of different grade， including massive magnetite. Chlorite geothermometry indicates formation of the Au-Ag-Bi-Te mineralization at temperatures between 300 and 250 °C， during the retrograde skarn evolution. Assuming the temperature is ～275°C， logfS2= -10.5 to -13， logfO2= -37 to -33， and logfTe2values range from approximately -12 to -8.5 were estimated. The available mineralogical and geological data (presences of magnetite， oxidized-type tellurides/sulfotellurides， and andraditic garnets， and absence of pyrrhotite and arsenopyrite) suggest that Aydindere is an oxidized Au-bearing skarn deposit. The discovery of Au-Ag-Bi-Te mineralization at Aydindere increases its productivity and requires more detailed exploration in the deposit for precious (Au， Ag) and critical (Bi， Te) metals.

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Using fracture-based continuum modeling of coupled geomechanical-hydrological processes for numerical simulation of hydraulic fracturing

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1582-1599页

作者： Goodluck i.Ofoegbu GNO Modeling Research LLC. San AntonioTX78253USA

This paper describes numerical simulation of hydraulic fracturing using fracture-based continuum modeling(FBCM)of coupled geomechanical-hydrological processes to evaluate a technique for high-density fracturing and fracture *** simulations are innovative because of modeling discrete fractures explicitly in continuum analysis.A key advantage of FBCM is that fracture initiation and propagation are modeled explicitly without changing the domain grid(*** re-meshing).Further,multiple realizations of a preexisting fracture distribution can be analyzed using the same domain *** simulated hydraulic fracturing technique consists of pressurizing multiple wells simultaneously:initially without permeating fluids into the rock,to seed fractures uniformly and at high density in the wall rock of the wells;followed by fluid injection to propagate the seeded fracture density *** combines the ease of continuum modeling with the potential accuracy of modeling discrete fractures and fracturing *** are modeled as piecewise planar based on intersections with domain elements;fracture geometry stored as continuum properties is used to calculate parameters needed to model individual fractures;and rock behavior is modeled through tensorial aggregation of the behavior of discrete fractures and unfractured *** are presented for previously unfractured rock and for rock with preexisting fractures of horizontal,shallow-dipping,steeply dipping,or vertical *** of a single-well model are used to determine the pattern and spacing for a multiple-well *** results illustrate high-density fracturing and fracture caging through simultaneous fluid injection in multiple wells:for previously unfractured rock or rock with preexisting shallow-dipping or horizontal fractures,and in situ vertical compressive stress greater than *** preexisting fractures are steeply dipping or vertical,and considering the same in situ

关键词： Discrete fracture Fracture-based continuum modeling Fracture caging High-density fracturing Hydraulic fracturing Preexisting fracture

Taxonomy,distribution,and contemporary exposure of terrestrial mammals to floods and human pressure across different areas for biodiversity conservation in China

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integrative Zoology 2024年第3期19卷 458-467页

作者： Roman SHARNUUD Eric i.AMECA MOE Key Laboratory for Biodiversity Science&Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijingChina Climate Change Specialist Group Species Survival CommissionInternational Union for Conservation of NatureGlandSwitzerland

A significant research focus is placed on identifying animal species and areas at future risk to human-induced alterations of the environment and long-term changes in climatic ***,the extent to which exposure to extreme climatic events and intense human pressure can increase the risk of harmful impacts on species remains poorly *** on terrestrial mammals in China,one of the world’s megadiverse countries,we investigated patterns of contemporary exposure to floods and human pressures and determined their taxonomic representation and distribution across three major area-based conservation schemes,namely,national nature reserves(NNRs),priority areas for biodiversity conservation(PABCs),and key biodiversity areas(KBAs).Among the 440 species assessed with moderate or high exposure to floods,327(∼75%)also qualified as moderate or high in exposure to intense human *** species mainly belong to the orders Chiroptera,Eulipotyphla,and ***,there were 305,311,and 311 species with moderate or high exposure to flood and intense human pressure represented across NNRs,PABCs,and KBAs,*** findings support the prioritization of KBAs for expansion of site-based protection efforts such as NNRs in China,considering threats to species from exposure to adverse effects from both extreme climate and human pressure.

关键词： conservation floods human pressure mammals taxonomy

Detection of 4p16.3 deletion and 11p15.5p15.4 gain in a boy by comparative genomic hybridization array:A case report

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World Journal of Clinical Cases 2024年第8期12卷 1517-1522页

作者： işın Kaya Medical Genetics Bakırçay UniversityÇiğli Education ve Training Hospitalİzmir 35620Turkey

BACKGROUND Nonallelic homologous recombination(NAHR)of segmental duplications or low copy repeats(LCRs)result in DNA gain/loss and play an important role in the origin of genomic *** SUMMARY A 3-year-old boy was referred for genetic *** genomic hybrid-ization array analysis revealed a loss of 3776 kb in the 4p16.3 chromosomal region and a gain of 3201 kb in the 11p15.5p15.4 chromosomal *** Genomic imbalances caused by NAHR in LCRs result in deletion and duplication syndromes.

关键词： Wolf-Hirschhorn syndrome Silver-Russell syndrome Recurrent rearrangements Case report

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： i.Sardar M.D.Hossain M.S.Sikder M.N.i.Khan M.R.Rahman Physics Discipline Khulna UniversityKhulna9208Bangladesh Department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Department ofComputer Science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh Material Science Division Atomic Energy CentreDhaka1000Bangladesh

Spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTiR),field emission scanning electron microscopy(FESEM),energy dispersive X-ray(EDX),vibrating sample magnetometer(VSM),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XRD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTiR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FESEM images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EDX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EDX Resistivity

High-temperature tribological performance of functionally graded Stellite 6/WC metal matrix composite coatings manufactured by laser-directed energy deposition

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Friction 2024年第3期12卷 522-538页

作者： Marta OSTOLAZA Alaitz ZABALA Jon inaki ARRiZUBiETA iñigo LLAVORi Nagore OTEGi Aitzol LAMiKiZ Department of Mechanical Engineering University of the Basque Country UPV/EHUPlaza Torres Quevedo 1Bilbo 48013Spain Faculty of Engineering Mechanics and Industrial ProductionMondragon UnibertsitateaLoramendi 4Mondragon 20500Spain

Wear-driven tool failure is one of the main hurdles in the *** issue can be addressed through surface coating with ceramic-reinforced metal matrix ***,the maximum ceramic content is limited by *** this work,the tribological behaviour of the functionally graded WC-ceramic-particlereinforced Stellite 6 coatings is *** that end,the wear resistance at room temperature and 400°C is ***,the tribological analysis is supported by crack sensitivity and hardness evaluation,which is of utmost importance in the processing of composite materials with *** indicate that functionally graded materials can be employed to increase the maximum admissible WC content,hence improving the tribological behaviour,most notably at high ***,a shift from abrasive to oxidative wear is observed in high-temperature wear testing.

关键词： friction coating metal matrix composite functionally graded materials high temperature laserdirected energy deposition

The Adsorption Properties of TEMPO Oxidized Cellulose against the Mixture of Methylene Blue and Rhemazol Yellow FG

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Journal of Renewable Materials 2024年第8期12卷 1369-1382页

作者： Mahendra, i. Putu Dinita, Kartika Program Studi Kimia Fakultas Sains Insitut Teknologi Sumatera Jalan Terusan Ryacudu Way Huwi Jati Agung Lampung Selatan 35365 Indonesia

TEMPO/NaOCl/NaBr treatment significantly increased the number of negative charges on the cellulose surface. Two concentrations of NaOCl, 5 and 30 mmol/g of cellulose, were used in this study. The number of carboxyl groups in the two cellulosic samples oxidized using TEMPO/NaOCl/NaBr was 0.5160 and 1.8461 mmol/g of cellulose, respectively. The oxidized cellulose samples treated with 5 and 30 mmol/g NaOCl exhibited higher crystallinity, at 81.15% and 80.14%, respectively, compared to untreated cellulose, which had a crystallinity of 75.95%. The pH effect indicated that the highest adsorption capacity for methylene blue was achieved under alkaline conditions (pH 9), while the highest adsorption capacity for rhemazol yellow FG was achieved under acidic conditions. The kinetic model of TEMPO-oxidized cellulose for methylene blue and rhemazol yellow FG conformed to the pseudo-second-order model. The initial concentration parameter revealed that the isotherm model for the adsorption of methylene blue and rhemazol yellow FG by TEMPO-oxidized cellulose conformed to the Langmuir model. The dye removal efficiencies for methylene blue and rhemazol yellow FG using TEMPO-oxidized cellulose (30 mmol/g) were approximately 80.17% and 59.52%, respectively. These results demonstrate that TEMPO/NaOCl/NaBr-oxidized samples can effectively separate cationic and anionic dye mixtures. Furthermore, the use of TEMPO-oxidized cellulose showed good regeneration capability, maintaining more than 95% of its adsorption capacity after 8 cycles. © 2024 The Authors.

关键词： Stripping (dyes)

Are population cycles recovering?

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integrative Zoology 2024年第3期19卷 538-547页

作者： Vasily D.YAKUSHOV Boris i.SHEFTEL A.N.Severtsov institute of Ecology and Evolution of the Russian Academy of Sciences MoscowRussia

The dynamics of populations of small mammals of Central Siberia was *** studies were carried out at the Yenisei ecological station“Mirnoye”of the *** institute of Ecology and Evolution,Russian Academy of *** time series analysis was performed by the wavelet transform using the statistical data processing language *** the 20th century,the dynamics of the population of the community and some of its constituent species(Sorex araneus;***;***;***;***;Craseomys rufocanus;Clethrionomys rutilus;Microtus oeconomus;***)were characterized by a 4-year *** type of dynamics changed to noncyclic by the nineties,but by 2022,four species(***,***,***,and ***)and the community as a whole showed a tendency toward recovery of population *** remaining species were characterized by consistently low numbers with irregular low amplitude fluctuations.

关键词： population cycles small mammals time-series analysis wavelet transform