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Nitrogen mineralization in the oldest climax communities in the eastern Mediterranean region

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Journal of Forestry Research 2024年第1期35卷 213-228页

作者： Fatma Selcen Sakar gürcan güleryüz Department of Biology Section Ecology GörükleGraduate School of Natural and Applied ScienceUniversity of Bursa Uludağ16059 NilüferBursaTurkey Department of Biology Section Ecology GörükleFaculty of Science and ArtsUniversity of Bursa Uludağ16059 NilüferBursaTurkey

In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest *** the oldest pure communi-ties of Pinus nigra(PN),Fagus orientalis(FO),and Abies bornmuelleriana(AB)in the mountain range of Mount uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 *** locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding capacity(%),organic c,total N,and c/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest *** had the highest annual net Nmin yield(43.9±4.8 kg ha^(-1) a^(-1)),*** the lowest(30.5±4.2 kg ha^(-1) a^(-1)).Our findings show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling and that hydrolyzed tannic acids and total phenolic compounds effectively control N *** acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification.

关键词： Oldest forest communities Nitrogen mineralization Nitrification Tannic acid Total phenolic Litter

changes in calcareous Nannofossil Assemblages and Paleoenvironmental Interpretation of the Early Miocene Lice Formation, Kahramanmara? Basin, Turkey, East Mediterranean

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Acta geologica Sinica(English Edition) 2024年第4期98卷 1021-1034页

作者： caner KAYAÖzER Muazez Esra ORHAN uğur TEMİz Yozgat Bozok university DivanlıRoadYozgat 66900Turkey

This study investigated the calcareous nannofossil assemblages in detail from the early Miocene aged Lice Formation outcropping in the Kahramanmara? basin. The biostratigraphy of calcareous nannofossils was outlined and paleoenvironmental features determined. In 81 samples taken from three measured sections in the region, 17 calcareous nannofossil genus and 48 nannofossil species were identified. These calcareous nannofossil genus and species identified the Lice Formation as being in the cNM4 nannofossil biozone. The abundance and diversity of early Miocene calcareous nannofossil species varied in the measured sections, with the samples generally moderate-poor, apart from a few samples. The relative abundance of individuals of cyclicargolithus floridanus, coccolithus pelagicus, Reticulofenestra hagii and Sphenolithus moriformis species, with paleoecological importance identified in the study region, indicate that in early Miocene times, the basin in which the Lice Formation deposited was meso-eutrophic with excess nutrient input, temperate and generally stable shallow marine conditions.

关键词： paleoecology nannofossil Burdigalian East Mediterranean

Atomistic Investigation of Shock-Induced Amorphization within Micro-shear Bands in Hexagonal close-Packed Titanium

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1590-1600页

作者： z.c.Meng K.g.Wang T.Ali D.Li c.g.Bai D.S.Xu S.J.Li A.H.Feng g.J.cao J.H.Yao Q.B.Fan H.Wang R.Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Interdisciplinary centre for Additive Manufacturing(IcAM) School of Materials and ChemistryUniversity of Shanghai for Science and TechnologyShanghai 200093China School of Materials Science and Engineering Tongji UniversityShanghai 201804China Key Laboratory for Light-Weight Materials Nanjing Tech UniversityNanjing 210009China National Key Laboratory of Science and Technology on Materials under Shock and Impact School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology chongqing Innovation center Chongqing 401135China

The mechanical response of a single crystal titanium sample against(0001)α surface impact was investigated using molecular dynamics ***,non-uniform plastic deformation was observed in the *** high strain rates,amorphization occurred near the edge of the contact region where severe shear strain induced a large number of stacking faults(SFs)and *** contrast,the central part of the contact region underwent less deformation with significantly fewer ***,instead of amorphization by consuming SFs and dislocations,there was a gradual increase in the density of dislocations and SFs during the process of *** local amorphous regions eventually grew into shear bands.

关键词： Shock compression Amorphization Shear band Titanium Molecular dynamics

In situ digital testing method for quality assessment of soft soil improvement with polyurethane

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Journal of Rock Mechanics and geotechnical Engineering 2024年第5期16卷 1732-1748页

作者： X.F.Wang c.J.Wang W.V.Yue z.J.zhang z.Q.Yue Department of civil Engineering China University of Geosciences (Beijing)BeijingChina Department of Water Science and Engineering Zhengzhou UniversityZhengzhouChina Department of geotechnical Engineering Tongji UniversityShanghaiChina Department of civil Engineering The University of Hong KongChina

This study purposes an in situ testing method on quality assessment of soil *** drilling data includes the spatial distribution and in situ strength of untreated and treated soil along three different drillholes measured by on-site drilling monitoring *** factual drilling data can characterize the degree of soil improvement by penetration injection with permeable *** from on-site drilling monitoring shows that the linear zones represent constant drilling speeds shown in the plot of drill bit advancement *** drilling time,which indicates the spatial distributions of soil *** soil profile at the study site is composed of four layers,which includes fill,untreated silty clay,treated silty clay,and mucky *** results of soil profile are verified by the parallel site *** constant drilling speeds profile the coring-resistant strength of drilled *** comparing with the untreated silty clay,the constant drilling speeds of the treated silty clay have been decreased by 13.0-62.8%.Two drilling-speed-based indices of 61.2%and 65.6%are proposed to assess the decreased average drilling speed and the increased in situ strength of treated silty *** tests,*** compressive strength(ucS)test,have been performed with core sample to investigate and characterize in situ strength by comparing that with drilling *** show that the average predicted strengths of treated silty clay are 2.4-6.9 times higher than the average measured strength of untreated silty *** ucS-based indices of 374.5%and 344.2%verified the quality assessment(QA)results by this new in situ *** method provides a cost-effective tool for quality assessment of soil improvement by utilizing the digital drilling data.

关键词： Drilling process monitoring system Hydraulic rotary drilling process constant drilling speed Soil improvement Quality assessment

Effect of Al_(2)O_(3)on the Mechanical Properties of(B_(4)c+Al_(2)O_(3))/Al Neutron Absorbing Materials

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1411-1420页

作者： J.X.cai B.M.Shi N.Li Y.Liu z.g.zhang Y.N.zan Q.z.Wang B.L.Xiao z.Y.Ma Shi‑changxu Innovation center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)c/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of B_(4)c/Al composites,in-situ nano-Al_(2)O_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)O_(3)content was adjusted by utilizing spheroid Al powder with varying diameters,thereby investigating the impact of Al_(2)O_(3)content on the tensile properties of(B_(4)c+Al_(2)O_(3))/Al *** was found that the pinning effect of Al_(2)O_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional B_(4)c/Al composites.

关键词： Al matrix composites Neutron absorbing materials (B_(4)c+Al_(2)O_(3))/Al composites High-temperature strength

construction of 2D/2D Ti_(3)c_(2)T_(x)MXene/cdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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Journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.Y.Huang z.Yang S.Y.Yang z.H.Dai Y.J.Liu J.H.Liao g.Y.zhong z.J.Xie Y.P.Fang S.S.zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)c_(2)T_(x)MXene/cdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)cdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of cdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure Photothermal effect Photocatalyst Hydrogen evolution

Distinct Electrical and Mechanical Responses of a cu-10Fe composite Prepared by Hot-Pressed Sintering and Post Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 255-265页

作者： X.Y.Yue S.Y.Peng X.zhang c.N.He Y.z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and Engineering and Tianjin Key Laboratory of composite and Functional Materials Tianjin UniversityTianjin300350China Research centre for Metallic Wires Northeastern UniversityShenyang110819China

A cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the cu-10wt%Fe *** cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IAcS and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance cu-based in-situ composites by post treatment.

关键词： cu-Fe composite Hot-pressed sintering Thermal stability Strength Electrical conductivity

Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan Q.Wang Y.chen W.B.Yao c.z.Xiao J.F.Myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and computational Mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIc)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by the 2D PIc simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

Impact of payment source, referral site, and place of residence on outcomes after allogeneic transplantation in Mexico

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World Journal of Transplantation 2024年第2期14卷 76-87页

作者： Andrés gómez-De León Yesica A López-Mora Valeria garcía-zárate Ana Varela-constantino Sergio u Villegas-De Leon Xitlaly J gonzález-Leal Raúl del Toro-Mijares Anna c Rodríguez-zúñiga Juan F Barrios-Ruiz Victor Mingura-Ledezma Perla R colunga-Pedraza Olga g cantú-Rodríguez césar H gutiérrez-Aguirre Luz Tarín-Arzaga Elías E gonzález-López David gómez-Almaguer Hematology Service Universidad Autónoma de Nuevo LeónFacultad de Medicina y Hospital Universitario Dr.JoséEleuterio GonzálezMonterrey 64460Nuevo LeónMexico Hemato-logy Service Clínica Gómez AlmaguerMonterrey 64710Nuevo LeónMexico Hematology Service Instituto Tecnológico de Estudios Superiores de MonterreyTec SaludEscuela de Medicina Ignacio SantosMonterrey 64710Nuevo LeónMexico

BAcKgROuND The impact of social determinants of health in allogeneic transplant recipients in low-and middle-income countries is poorly *** observational study analyzes the impact of place of residence,referring institution,and transplant cost coverage(out-of-pocket vs government-funded vs private insurance)on outcomes after allogeneic hematopoietic stem cell transplantation(alloHScT)in two of Mexico's largest public and private *** To evaluate the impact of social determinants of health and their relationship with outcomes among allogeneic transplant recipients in *** In this retrospective cohort study,we included adolescents and adults≥16 years who received a matched sibling or haploidentical transplant from *** were selected without regard to their diagnosis and were sourced from both a private clinic and a public university Hospital in *** payment groups were compared:Out-of-pocket(OOP),private insurance,and a federal universal healthcare program“Seguro Popular”.Outcomes were compared between referred and institution-diagnosed patients,and between residents of Nuevo Leon and *** outcomes included overall survival(OS),categorized by residence,referral,and payment *** outcomes encompassed early mortality,event-free-survival,graft-versus-host-relapse-free survival,and non-relapse-mortality(NRM).Statistical analyses employed appropriate tests,Kaplan-Meier method,and cox proportional hazard regression *** software included SPSS and R with tidycmprsk *** Our primary outcome was overall *** included 287 patients,n=164 who lived out of state(57.1%),and n=129 referred from another institution(44.9%).The most frequent payment source was OOP(n=139,48.4%),followed by private insurance(n=75,26.1%)and universal coverage(n=73,25.4%).No differences in OS,event-free-survival,NRM,or graft-versus-host-relapse-free survival were observed for patients dia

关键词： Hematopoietic cell transplant Social determinants of health geography Haploidentical Out-of-pocket Financial toxicity Survival Health services and outcomes Hematopoietic malignancy Aplastic anemia