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Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2)-xO_(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 devices.For the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important issues.This 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)-xO_(4) ferrites,where x=0.00,0.06,and 0.10.The 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 samples.The XRD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped samples.The 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 concentration.The FTiR analysis also proves the spinel cubic phase of the samples.The average grain size of the ferrites is obtained via FESEM images,and it is increased from 121 to 198 nm.VSM 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)-xO_(4) ferrites.Particularly,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 ferrites.The permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric losses.Frequency dependent resistivity and impedance analysis also show the improved nature.From 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

Continuous ward monitoring and intensive postoperative management

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Chinese Medical Journal 2024年第6期137卷 631-632页

作者： Kai Li Jiayi Wang Daniel i.Sessler Department of Anesthesiology China-Japan Union HospitalJilin UniversityChangchunJilin 130031China Outcomes Research Consortium ClevelandOhio 44195USA Department of Anesthesiology Shanghai Ninth People’s HospitalShanghai JiaoTong University School of MedicineShanghai 201999China Department of Outcomes Research Cleveland ClinicClevelandOhio 44195USA

When patients having major surgery reach the post-anaesthesia care unit,families naturally assume that they have survived the most dangerous part of the perioperative experience.Their assumption is wrong.Mortality in the 30 days after surgery is 140 times higher than intraoperative mortality.^([1,2])in fact,if the month after surgery were considered a disease,it would be the world’s third leading cause of death.^([3])

关键词： assume dangerous wrong

Post processing of additive manufactured Mg alloys:Current status,challenges,and opportunities

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Journal of Magnesium and Alloys 2024年第4期12卷 1283-1310页

作者： Nooruddin Ansari Fatima Ghassan Alabtah Mohammad i.Albakri Marwan Khraisheh Mechanical Engineering Program Texas A&M University at QatarP.O.Box 23874DohaQatar

Magnesium(Mg)and its alloys are emerging as a structural material for the aerospace,automobile,and electronics industries,driven by the imperative of weight reduction.They are also drawing notable attention in the medical industries owing to their biodegradability and a lower elastic modulus comparable to bone.The ability to manufacture near-net shape products featuring intricate geometries has sparked huge interest in additive manufacturing(AM)of Mg alloys,reflecting a transformation in the manufacturing sectors.However,AM of Mg alloys presents more formidable challenges due to inherent properties,particularly susceptibility to oxidation,gas trapping,high thermal expansion coefficient,and low solidification temperature.This leads to defects such as porosity,lack of fusion,cracking,delamination,residual stresses,and inhomogeneity,ultimately influencing the mechanical,corrosion,and surface properties of AM Mg alloys.To address these issues,post-processing of AM Mg alloys are often needed to make them suitable for application.The present article reviews all post-processing techniques adapted for AM Mg alloys to date,including heat treatment,hot isostatic pressing,friction stir processing,and surface peening.The utilization of these methods within the hybrid AM process,employing interlayer post-processing,is also discussed.Optimal post-processing conditions are reported,and their influence on the microstructure,mechanical,and corrosion properties are detailed.Additionally,future prospects and research directions are proposed.

关键词： Magnesium alloy Additive manufacturing Post-processing Heat treatment HiP

VR-based digital twin for remote monitoring of mining equipment:Architecture and a case study

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 100-112页

作者： Jovana PLAVŠiĆ ilija MiŠKOViĆNorman BKeevil Norman B.Keevil institute of Mining Engineering University of British ColumbiaVancouverBC V6T 1Z4Canada

Background Traditional methods for monitoring mining equipment rely primarily on visual inspections,which are time-consuming,inefficient,and hazardous.This article introduces a novel approach to monitoring mission-critical systems and services in the mining industry by integrating virtual reality(VR)and digital twin(DT)technologies.VR-based DTs enable remote equipment monitoring,advanced analysis of machine health,enhanced visualization,and improved decision making.Methods This article presents an architecture for VR-based DT development,including the developmental stages,activities,and stakeholders involved.A case study on the condition monitoring of a conveyor belt using real-time synthetic vibration sensor data was conducted using the proposed methodology.The study demonstrated the application of the methodology in remote monitoring and identified the need for further development for implementation in active mining operations.The article also discusses interdisciplinarity,choice of tools,computational resources,time and cost,human involvement,user acceptance,frequency of inspection,multiuser environment,potential risks,and applications beyond the mining industry.Results The findings of this study provide a foundation for future research in the domain of VR-based DTs for remote equipment monitoring and a novel application area for VR in mining.

关键词： Virtual reality Digital twin Condition monitoring Mining equipment

Dominance of transposable element‑related satDNAs results in great complexity of“satDNA library”and invokes the extension towards“repetitive DNA library”

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Marine Life Science & Technology 2024年第2期6卷 236-251页

作者： Monika Tunjić‑Cvitanić Daniel García‑Souto Juan J.Pasantes EvaŠatović‑Vukšić Division of Molecular Biology Ruđer BoškovićInstitute10000 ZagrebCroatia Genomes and Disease Centre for Research in Molecular Medicine and Chronic Diseases(CIMUS)Universidade de Santiago de Compostela15706 Santiago de CompostelaSpain Department of Zoology Genetics and Physical AnthropologyUniversidade de Santiago de Compostela15706 Santiago de CompostelaSpain Centro de investigación Mariña Dpto de BioquímicaXenética e InmunoloxíaUniversidade de Vigo36310 VigoSpain

Research on bivalves is fast-growing,including genome-wide analyses and genome sequencing.Several characteristics qualify oysters as a valuable model to explore repetitive DNA sequences and their genome organization.Here we char-acterize the satellitomes of five species in the family Ostreidae(Crassostrea angulata,C.virginica,C.hongkongensis,C.ariakensis,Ostrea edulis),revealing a substantial number of satellite DNAs(satDNAs)per genome(ranging between 33 and 61)and peculiarities in the composition of their satellitomes.Numerous satDNAs were either associated to or derived from transposable elements,displaying a scarcity of transposable element-unrelated satDNAs in these genomes.Due to the non-conventional satellitome constitution and dominance of Helitron-associated satDNAs,comparative satellitomics demanded more in-depth analyses than standardly employed.Comparative analyses(including C.gigas,the first bivalve species with a defined satellitome)revealed that 13 satDNAs occur in all six oyster genomes,with Cg170/Hindiii satDNA being the most abundant in all of them.Evaluating the“satDNA library model”highlighted the necessity to adjust this term when studying tandem repeat evolution in organisms with such satellitomes.When repetitive sequences with potential variation in the organizational form and repeat-type affiliation are examined across related species,the introduction of the terms“TE library”and“repetitive DNA library”becomes essential.

关键词： Satellitome Comparative satellitomics Helitron Bivalves “Dark matter of the genome”

Rice Husk at a Glance:From Agro-industrial to Modern Applications

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Rice science 2024年第1期31卷 14-32页

作者： Masoumeh KORDi Naser FARROKHi Martin i.PECH-CANUL Asadollah AHMADiKHAH Department of Cell&Molecular Biology Faculty of Life Sciences and BiotechnologyShahid Beheshti UniversityTehran ***Iran 1062 Metallurgical industry Avenue Industrial Park Saltillo-Ramos ArizpeRamos ArizpeCoahuila 25900Mexico

Excessive waste production has led to the concept of a circular bioeconomy to deliver valuable by-products and improve environmental sustainability.The annual worldwide rice production accounts for more than 750 million tons of grain and 150 million tons of husk.Rice husk(RH)contains valuable biomaterials with extensive applications in various fields.The proportions of each component depend primarily on rice genotype,soil chemistry,and climatic conditions.RH and its derivatives,including ash,biochar,hydrochar,and activated carbon have been placed foreground of applications in agriculture and other industries.While the investigation on RH’s compositions,microstructures,and by-products has been done copiously,owing to its unique features,it is still an open-ended area with enormous scope for innovation,research,and technology.Here,we reviewed the latest applications of RH and its derivatives,including fuel and other energy resources,construction materials,pharmacy,medicine,and nanobiotechnology to keep this versatile biomaterial in the spotlight.

关键词： circular bioeconomy rice husk activated carbon rice husk ash rice husk biochar rice husk hydrochar rice husk application

improving antioxidant activities of water-soluble lignin-carbohydrate complex isolated from wheat stalk through prolonging ball-milling pretreatment and homogeneous extraction

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Journal of Bioresources and Bioproducts 2024年第1期9卷 113-125页

作者： Di Xie Zhulan Liu Yunfeng Cao Sheng-i Yang Chen Su Mi Li Jiangsu Co-innovation Center for Efficient Processing and Utilization of Forest Products Nanjing Forestry UniversityNanjing 210037China international innovation Center for Forest Chemicals and Materials Nanjing Forestry UniversityNanjing 210037China Center for Renewable Carbon School of Natural ResourcesUniversity of TennesseeKnoxvilleTN 37996USA Shandong Huatai Paper Co. Ltd.Dongying 257000China School of Natural Resources University of TennesseeKnoxvilleTN 37996USA Key Lab of Biomass Energy and Material Institute of Chemical Industry of Forest ProductsChinese Academy of ForestryJiangsu ProvinceNanjing 210042China

Water-soluble lignin-carbohydrate complex(LCC)rich in polysaccharides exhibits benign in vitro antioxidant activities and distinguishes high biocompatibility from lignin-rich LCC and lignin.However,the antioxidant activity of water-soluble LCCs remains to be improved and its structure-antioxidant relationship is still uncertain.Herein,structurally diversified water-soluble LCCs were isolated under different ball-milling pretreatment durations(4,6,8 h),extraction pathways(ho-mogeneous and heterogeneous),and isolation routines(water extracts and residues after water extraction).Their structures were characterized by wet chemistry,chromatography and spec-troscopies.Antioxidant activities were evaluated by ferric reducing antioxidant power and 1,1-diphenyl-2-picrylhydrazyl radicals scavenging rate(RDPPH).Results show that altering ball-milling duration and isolation procedures cause varied structures and antioxidant activities of the water-soluble LCCs.Specifically,prolonging ball-milling duration to 8 hours and homogeneous extrac-tion can enhance their antioxidant activity through releasing more phenolic structures and pro-moting the extraction of high-molecular-weight LCCs via reducing mass-transfer resistance,re-spectively.As a result,the RDPPH of water-soluble LCCs reaches up to 97.35%,which is associated with the arabinan content with statistical significance(Pis study provides new insights into the structure-antioxidation relationship of herbaceous LCC as potential antioxidants.

关键词： LCC Homogeneous extraction Ball-milling Structure-antioxidation relationship Wheat straw

Phase composition,conductivity,and sensor properties of cerium-doped indium oxide

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Nano Materials Science 2024年第2期6卷 193-200页

作者： M.i.ikim G.N.Gerasimov V.F.Gromov O.J.ilegbusi L.i.Trakhtenberg N.N.Semenov Federal Research Center for Chemical Physics of RAS MoscowRussia University of Central Florida OrlandoFLUSA Moscow institute of Physics and Technology(State University) DolgoprudnyMoscow RegionRussia Lomonosov Moscow State University MoscowRussia

The hydrothermal synthesis of in_(2)O_(3)and CeO_(2)–in_(2)O_(3)is investigated as well as the properties of sensor layers based on these compounds.During the synthesis of in_(2)O_(3),intermediate products in(OH)_(3)and inOOH are formed,which are the precursors of stable cubic(c-in_(2)O_(3))and metastable rhombohedral(rh-in_(2)O_(3))phases,respectively.A transition from c-in_(2)O_(3)to rh-in_(2)O_(3)is observed with the addition of CeO_(2).The introduction of cerium into rh-in_(2)O_(3)results in a decrease in the sensor response to hydrogen,while it increases in composites based on c-in_(2)O_(3).The data on the sensor activity of the composites correlate with XPS results in which CeO_(2)causes a decrease in the concentrations of chemisorbed oxygen and oxygen vacancies in rh-in_(2)O_(3).The reverse situation is observed in composites based on c-in_(2)O_(3).Compared to in_(2)O_(3)and CeO_(2)–in_(2)O_(3)obtained by other methods,the synthesized composites demonstrate maximum response to H_(2)at low temperatures by 70–100℃,and have short response time(0.2–0.5 s),short recovery time(6–7 s),and long-term stability.A model is proposed for the dependence of sensitivity on the direction of electron transfer between in_(2)O_(3)and CeO_(2).

关键词： Cerium oxide indium oxide Nanocomposite Hydrothermal method Cubic phase Rhombohedral phase Sensor response Conductivity Hydrogen Response/recovery time

A Statistical Study of Magnetic Flux Emergence in Solar Active Regions Prior to Strongest Flares

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Research in Astronomy and Astrophysics 2024年第4期24卷 147-160页

作者： Alexander S.Kutsenko Valentina i.Abramenko Andrei A.Plotnikov Crimean Astrophysical Observatory p/o NauchnyCrimea298409Russia

Using the data on magnetic field maps and continuum intensity for Solar Cycles 23 and 24,we explored 100 active regions(ARs)that produced M5.0 or stronger flares.We focus on the presence/absence of the emergence of magnetic flux in these ARs 2-3 days before the strong flare onset.We found that 29 ARs in the sample emerged monotonically amidst quiet-Sun.A major emergence of a new magnetic flux within a pre-existing AR yielding the formation of a complex flare-productive configuration was observed in another 24 cases.For 30 ARs,an insignificant(in terms of the total magnetic flux of pre-existing AR)emergence of a new magnetic flux within the pre-existing magnetic configuration was observed;for some of them the emergence resulted in a formation of a configuration with a small δ-sunspot;11 out of 100 ARs exhibited no signatures of magnetic flux emergence during the entire interval of observation.in six cases the emergence was in progress when the AR appeared on the Eastern limb,so that the classification and timing of emergence were not possible.We conclude that the recent flux emergence is not a necessary and/or sufficient condition for strong flaring of an AR.The flux emergence rate of flare-productive ARs analyzed here was compared with that of flare-quiet ARs analyzed in our previous studies.We revealed that the flare-productive ARs tend to display faster emergence than the flare-quiet ones do.

关键词： Sun:activity Sun:flares Sun:magnetic fields