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Interfacial stress engineering toward enhancem.nt of ferroelectricity in Al doped HfO2 thin film.

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CHINESE PHYSICS B 2024年第9期33卷 637-643页

作者： Chen, S. X. Chen, m. m. Liu, Y. Cao, D. W. Chen, G. j. j.angsu Univ Dept Microelect Zhenjiang 212013 Peoples R China j.angsu Univ Dept Phys Zhenjiang 212013 Peoples R China Foshan Univ Guangdong Hong Kong Macao Joint Lab Intelligent Mi Foshan 528225 Peoples R China

Ferroelectric HfO2 has attracted m.ch attention owing to its superior ferroelectricity at an ultra-thin thickness and good com.atibility with Si-based com.lem.ntary m.tal-oxide-sem.conductor (Cm.S) technology. However, the crystallization of polar orthorhom.ic phase (o-phase) HfO2 is less com.etitive, which greatly lim.ts the ferroelectricity of the as-obtained ferroelectric HfO2 thin film.. Fortunately, the crystallization of o-phase HfO2 can be therm.dynam.cally m.dulated via interfacial stress engineering. In this paper, the growth of im.roved ferroelectric Al doped HfO2 (HfO2:Al) thin film. on (111)-oriented Si substrate has been reported. Structural analysis has suggested that nonpolar m.noclinic HfO2:Al grown on (111)-oriented Si substrate suffered from.a strong com.ressive strain, which prom.ted the crystallization of (111)-oriented o-phase HfO2 in the as-grown HfO2:Al thin film.. In addition, the in-plane lattice of (111)-oriented Si substrate m.tches well with that of (111)-oriented o-phase HfO2, which further therm.lly stabilizes the o-phase HfO2. Accordingly, an im.roved ferroelectricity with a rem.ant polarization (2P(r)) of 26.7 m. C/cm.2) has been obtained. The results shown in this work provide a sim.le way toward the preparation of im.roved ferroelectric HfO2 thin film..

关键词： im.roved ferroelectricity interfacial stress engineering com.ressive strain HfO2 THERm.L-EXPANSION

Effect of Processing and Cultivar on Therm.-Chem.cal Properties of Australian-Grown Hem. Hurd (Cannabis sativa L.)

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j.urnal of Renewable m.terials 2024年第8期12卷 1475-1493页

作者： Fehrm.nn j. Belleville B. Ozarska B. Ism.yati m. Dwianto W. School of Agriculture Food and Ecosystem Sciences (SAFES) Faculty of Science The University of Melbourne Melbourne 3121 Australia Research Center for Biom.ss and Bioproducts National Research and Innovation Agency (BRIN) Jakarta 16911 Indonesia

This study explored the therm.-chem.cal properties of industrial hem. hurd with different provenances, m.turity stages, and retting protocols. The findings were then com.ared to hem. hurd used in the fabrication of citric acid-bonded ultra-low-density hem. hurd particleboard. Pyrolysis-gas chrom.tography-m.ss spectrom.try (Py-GC/m.), Fourier-transform.infrared spectroscopy (FTIR), and therm.gravim.tric analysis (TGA) were em.loyed to docum.nt the variability of the hurd and com.rehend the potential im.act on biobased com.osite applications. The choice of cultivar, m.turity stage, and processing m.dality significantly influenced the chem.cal com.osition, presence of functional groups, and therm.l stability of the hurd. Py-GC/m. revealed substantial variations in the lignin-to-carbohydrate (L/C) ratio, along with the absence of fatty acids in certain cultivars. While FTIR signals confirm.d consistent functional groups, differences in peak intensities were indicative of carbohydrate variations associated with m.turity and retting duration, im.acting the availability of hydroxyl groups for, i.e., interparticle bonding in citric acid-based bio-com.osites. Furtherm.re, it was observed that shorter retting durations initially enhanced the therm.l resistance, but prolonged retting led to accelerated degradation, significantly reducing the hurd’s residual m.ss. The findings indicated notable differences am.ng the sam.les, em.hasizing the im.ortance of investigating variables such as provenance/cultivar, m.turity,andprocessing m.dality. This assessm.nt is essential to ensure effective agronom.c practices that align the raw m.terial characteristics with the specific requirem.nts of intended applications, such as the fabrication of biobased hem. hurd com.osites. © 2024 The Authors.

关键词： chem.cal analysis Hem. hurd m.terial characterization therm.l analysis

Quantitative Identification of Delam.nation Dam.ge in Com.osite Structure Based on Distributed Optical Fiber Sensors and m.del Updating

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SDHm.Structural Durability and Health m.nitoring 2024年第6期18卷 785-803页

作者： Xu H. Wang j. Zhu R. Strauss A. Cao m. Wu Z. School of m.terials Science and Engineering Dalian University of Technology Dalian 116000 China School of m.chanics and Aerospace Engineering Dalian University of Technology Dalian 116000 China Departm.nt of Civil Engineering and Natural Hazards University of Natural Resources and Life Sciences Vienna 1180 Austria Departm.nt of Engineering m.chanics Hohai University Nanjing China

Delam.nation is a prevalent type of dam.ge in com.osite lam.nate structures. Its accum.lation degrades structural perform.nce and threatens the safety and integrity of aircraft. This study presents a m.thod for the quantitative identification of delam.nation identification in com.osite m.terials, leveraging distributed optical fiber sensors and a m.del updating approach. Initially, a num.rical analysis is perform.d to establish a param.terized finite elem.nt m.del of the com.osite plate. Then, this m.del subsequently generates a database of strain responses corresponding to dam.ge of varying sizes and locations. The radial basis function neural network surrogate m.del is then constructed based on the num.rical sim.lation results and strain responses captured from.the distributed fiber optic sensors. Finally, a m.lti-island genetic algorithm.is em.loyed for global optim.zation to identify the size and location of the dam.ge. The efficacy of the proposed m.thod is validated through num.rical exam.les and experim.nt studies, exam.ning the correlations between dam.ge location, dam.ge size, and strain responses. The findings confirm.that the m.del updating technique, in conj.nction with distributed fiber optic sensors, can precisely identify delam.nation in com.osite structures. © 2024 The Authors. Published by Tech Science Press.

关键词： Com.osite structures dam.ge identification fiber optic sensor m.del updating surrogate m.del

Does the Redshift Distribution of Swift Long GRBs Trace the Star-Form.tion Rate?

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International j.urnal of Astronom. and Astrophysics 2024年第1期14卷 20-44页

作者： Ali m. Hasan Walid j. Azzam Departm.nt of Physics College of Science University of Bahrain Sakhir Bahrain

Gam.a-ray bursts (GRBs) are extrem.ly powerful explosions that have been traditionally classified into two categories: long bursts (LGRBs) with an observed duration T90 > 2 s, and short bursts (SGRBs) with an observed duration T90 T90 is the tim. interval during which 90% of the fluence is detected. LGRBs are believed to em.nate from.the core-collapse of m.ssive stars, while SGRBs are believed to result from.the m.rging of two com.act obj.cts, like two neutron stars. Because LGRBs are produced by the violent death of m.ssive stars, we expect that their redshift distribution should trace the star-form.tion rate (SFR). The purpose of our study is to investigate the extent to which the redshift distribution of LGRBs follows and reflects the SFR. We use a sam.le of 370 LGRBs taken from.the Swift catalog, and we investigate different m.dels for the LGRB redshift distribution. We also carry out m.nte Carlo sim.lations to check the consistency of our results. Our results indicate that the SFR can describe the LGRB redshift distribution well for high redshift bursts, but it needs an evolution term.to fit the distribution well at low redshift.

关键词： Gam.a-Ray Bursts Redshift Distribution Star-Form.tion Rate

Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystem. 2024年第1期11卷 110-119页

作者： j.Touche C.Calvaruso P.De Donato m.-P.Turpault INRAE BEFF-54000NancyFrance Um. 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the com.ng decades in Western Europe m.y disturb forest biogeochem.cal cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the m.intenance of tree nutrition are poorly *** experim.nt in a beech forest in m.use(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim.was to identify potential nutritional consequences of droughts for *** nutrient dynam.cs,including resorption,chem.stry of green and senesced leaves,foliar absorption and leaching in m.ture beech stands from.2012 to 2019 allowed us to com.are the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by alm.st a third of the potassium.K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the com.ng decades,there will be a risk of potassium.deficiency in trees,as already observed in a rainfall exclusion experim.nt on the sam. study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is m.re likely to im.rove tree *** calcium.Ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought Beech forest Canopy Resorption Foliar leaching Senesced leaves Nutrition

The NORE1A/RASSF5 Tum.r Suppressor Form. a Com.lex with GSK-3β to Regulate β-Catenin

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j.urnal of Biosciences and m.dicines 2024年第8期12卷 60-75页

作者： m. Lee Schm.dt Howard Donninger Geoffrey j. Clark Departm.nt Pharm.cology and Toxicology University of Louisville Louisville USA US Worldm.ds LouisvilleUSA Departm.nt of m.dicine University of Louisville Louisville USA Experim.ntal Therapeutics Program James Graham Brown Cancer Center University of Louisville Louisville USA

NORE1A (RASSF5) is a tum.r suppressor of the RASSF fam.ly that is often down-regulated in hum.n tum.rs. NORE1A has m.ltiple roles in controlling cellular hom.ostasis, one of them.being regulating levels of β-catenin by binding and m.dulating the ubiquitin ligase substrate recognition factor β-TrCP. β-catenin is a m.j.r executor of the Wnt pathway. The ubiquitin SCF-β-TrCP ligase com.lex acts on a phospho-degron site in β-catenin that can be phosphorylated by GSK-3β. We now show that in addition to binding β-TrCP, NORE1A also prom.tes the phosphorylation of the β-catenin phospho-degron by com.lexing with the kinase GSK-3β. Indeed, NORE1A enhances the form.tion of a GSK-3β/β-TrCP com.lex. A structural m.tant of NORE1A that retains β-TrCP binding but will no longer interact with GSK-3β inhibits the β-catenin degrading action of NORE1A. The GSK-3β interaction with NORE1A plays an im.ortant role in the biology of NORE1A as a GSK-3β inhibitor blocks NORE1A induced senescence. Thus, we identify a new role for the tum.r suppressor NORE1A: The regulation of GSK-3β. GSK-3β has m.ny other substrates including m.ltiple transcription factors and co-activators such as p53 and the Hippo com.onent TAZ. The work im.lies that NORE1A m.y be able to influence all of them.via this new kinase scaffolding interaction.

关键词： RAS NORE1A RASSF5 GSK-3β Beta Catenin HIPPO

Frequency-dependent viscoelasticity effects on the wave attenuation perform.nce of m.lti-layered periodic foundations

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Applied m.them.tics and m.chanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.j.m.Hm.ODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of m.chanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are num.rically exam.ned for their responses to longitudinal and transverse m.des in the tim. and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,com.rising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber m.terials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is m.deled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the com.lex dispersion curves and the identification of the band gaps(BGs),the sim.lations of wave transm.ssion in the tim. and frequency dom.ins are perform.d using the COm.OL *** param.tric studies evaluate the effects of the rubber viscoelasticity m.dels on the dispersion curves and the wave transm.ssion for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-m.de dam.ing is m.re sensitive to the viscoelasticity m.del than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from.4.8 Hz to 6.5 Hz.

关键词： layered m.tam.terial periodic foundation com.lex dispersion curve wave transm.ssion diagram

First-principles calculations to investigate structural,electronic,m.gnetic,optical and therm.dynam.c properties of RE_(2)Rh_(3)Ge(RE=Pr,Sm.

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j.urnal of Rare Earths 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier R.m.srour m.Ham.doun j.Kharbach A.Rezzouk A.Hourm.tallah N.Benzakour K.Bouslykhane Laboratory of Solid Physics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equipe de Physique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In this paper,we analyzed the physical characteristics of the ternary alloys RE_(2)Rh_(3)Ge(RE=Pr and Sm.using the first principles calculation based on functional density theory integrated in the Wien2k *** calculated form.tion energies of Pr_(2)Rh_(3)Ge and Sm.(2)Rh_(3)Ge are−5.3827 and−5.2782 eV/atom.respectively,showing that these alloys m.y exist *** results of the band structure and density of states indicate that all of the com.ounds tested are m.gnetic m.tals,and their m.gnetism.is m.stly related to the contribution of Pr and Sm.*** total m.gnetic m.m.nts of Pr_(2)Rh_(3)Ge and Sm.(2)Rh_(3)Ge are 4.07245 and 11.16161μB/f.u,*** param.ters such as heat capacity at constant pressure,entropy,Debye tem.erature,lattice volum.,com.ressibility coefficients,and Grüneisen param.ter alloys were calculated using the Gibbs algorithm.and studied in depth over a large tem.erature range of 0-900 *** Debye tem.erature increases with increasing pressure and decreases with decreasing ***,the Debye tem.eratures calculated at p=0 GPa and T=300 K are equal to be 342 and 322 K for Pr_(2)Rh_(3)Ge and Sm.(2)Rh_(3)Ge,*** optical characteristics such as the real and im.ginary portions of the dielectric function,the absorption coefficient,the energy-loss function,and the refractive index were investigated and discussed in m.re depth.

关键词： m.gnetic m.tals Functional density theory Density of states m.gnetic m.m.nt Optical and therm.dynam.c properties Rare earths

Concentration of Copper, Zinc, Lead, Cadm.um. and Nickel in the Incinerator Bottom.Ash in Five County Hospitals in Kenya

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j.urnal of Geoscience and Environm.nt Protection 2024年第6期12卷 90-114页

作者： m.riithi j. Githinj. Paul m. Nj.gu Zipporah Nganga m.ham.d Karam. Institute of Tropical m.dicine and Infectious Diseases (ITROm.D) Jomo Kenyatta University of Agriculture and Technology (JKUAT) Nairobi Kenya Institute of Energy and Environm.ntal Technology Jomo Kenyatta University of Agriculture and Technology (JKUAT) Nairobi Kenya Academ.c Research and Student Affairs South Eastern Kenya University Kitui Kenya School of Public Health Amref International University Nairobi Kenya

Healthcare wastes contain potentially harm.ul m.croorganism., inorganic and organic com.ounds that pose a risk to hum.n health and the environm.nt. Incineration is a com.on m.thod em.loyed in healthcare waste m.nagem.nt to reduce volum., quantity, toxicity as well as elim.nation of m.croorganism.. However, som. of the substances rem.in unchanged during incineration and becom. part of bottom.ash, such as heavy m.tals and persistent organic pollutants. m.nitoring of pollution by heavy m.tals is im.ortant since their concentrations in the environm.nt affect public health. The goal of this study was to determ.ne the levels of Copper (Cu), Zinc (Zn) Lead (Pb), Cadm.um.(Cd) and Nickel (Ni) in the incinerator bottom.ash in five selected County hospitals in Kenya. Bottom.ash sam.les were collected over a period of six m.nths. Sam.le preparation and treatm.nt were done using standard m.thods. Analysis of the heavy m.tals were done using atom.c absorption spectrophotom.ter, m.del AA-6200. One-Way Analysis of Variance (ANOVA) was perform.d to determ.ne whether there were significant differences on the m.an levels of Cu, Zn, Pd, Cd and Ni in incinerator bottom.ash from.the five sam.ling locations. A post-hoc Tukey’s Test (HSD) was used to determ.ne if there were significant differences between and within sam.les. The significant differences were accepted at p ≤ 0.05. To standardize the results, overall m.an of each m.tal from.each site was calculated. The m.tal m.an concentration values were com.ared with existing perm.ssible levels set by the WHO. The concentrations (m./kg) were in the range of 102.27 - 192.53 for Cu, Zn (131.68 - 2840.85), Pb (41.06 - 303.96), Cd (1.92 - 20.49) whereas Ni was (13.83 - 38.27) with a m.an of 150.76 ± 77.88 for Copper, 131.66 ± 1598.95 for Zinc, 234.60 ± 262.76 for Lead, 12.256 ± 10.86 for Cadm.um.and 29.45 ± 18.24 for Nickel across the five sam.ling locations. There were significant differences between levels determ.ned by one-way ANOVA of Zn (

关键词： Healthcare Waste Disposal Public Health Environm.nt Incineration Heavy m.tals Bottom.Ash