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海南岛万泉河口沉积物有机碳、氮同位素的特征及其环境意义

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第四纪研究 2007年第5期27卷 845-852页

作者：葛晨东王颖 t.f.pedersen O.Slaymaker 南京大学海岸与海岛开发教育部重点实验室南京210093 School of Earthand Ocean Sciences The University of VictoriaVictoriaBCV8W3P6 Department of Geography The University of British ColumbiaVancouverBCV6T1Z2

对海南岛万泉河口沙美内海柱样K3和K4沉积物进行生物地球化学指标总有机碳(tOC)、总氮(tN)、有机碳同位素(δ13C)、氮同位素(δ15N)的分析,以及210Pb定年了解其近代变化特征,追踪沉积物有机质来源的变化,提取沉积环境演变及人类活动的... 详细信息

对海南岛万泉河口沙美内海柱样K3和K4沉积物进行生物地球化学指标总有机碳(tOC)、总氮(tN)、有机碳同位素(δ13C)、氮同位素(δ15N)的分析,以及210Pb定年了解其近代变化特征,追踪沉积物有机质来源的变化,提取沉积环境演变及人类活动的信息。K3中tOC的变化介于0.51%~1.12%,K4变化介于0.43%~1.49%,而其随时间的变化反映了流域内人类活动的历史。17世纪tOC含量明显增加记录了明末清初开始流域内广泛种植农作物的活动,19世纪以来tOC含量逐渐增加,至现代达最高值,对应了工业革命以来人类活动的增强。K3和K4的δ13C值变化分别在-24.38‰^-21.02‰之间和-24.74‰^-20.17‰之间,δ15N值变化分别在2.20‰~4.62‰之间和2.39‰~5.02‰之间,映证了本区沉积物有机质是陆源物质和海洋物质混合的特点。明末清初开始流域内广泛种植玉米等农作物造成δ13C值增加和δ15N值减少;自19世纪以来至现在,该区的经济活动增加,人口的持续增长,尤其是近50年来化肥农药的大量使用,造成陆源输入的有机碳含量大幅增加,使δ13C值减少和δ15N比值增加。δ13C值自19世纪以来就逐渐变轻,说明陆源和海洋有机碳的比例发生了变化,较轻的陆源有机碳比例相对增加,较重的海洋有机碳比例相对减少,反映了玉带滩沙坝的增长、沙美内海封闭、海水交换作用减少的状况。C/N比值分别从底部的16.19和17.36到顶部减小为11左右,自19世纪以来呈明显减小的趋势也反映了沙美内海泻湖自生的藻类有机质供应越来越多,也说明了其逐渐封闭、水动力条件越来越弱,与外海的交换作用逐渐减少的状况。

关键词： tOC δ13^C值和δ15^N值 C/N 环境演变人类活动海南岛万泉河口

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海南岛万泉河口沉积环境演变

科学通报 2003年第19期48卷 2079-2083页

作者：葛晨东 O.Slaymaker t.f.pedersen 南京大学海岸与海岛开发教育部重点实验室南京210093 Department of Geography The University of British ColumbiaVancouver BC V6T 1Z2 Canada School of Earth and Ocean Sciences The University of Victoria Victoria BC V8W 3P6 Canada.

根据对柱样沉积物^(21’)Pb定年及有机碳、硫和有机碳同位素含量分析,研究万泉河口沉积环境演变。硫和δ^(13)C均自19世纪初期开始持续减少,硫从1.92％逐渐减少到0.36％,δ^(13)C从-20.63‰减少到-23.64‰。C/S比在20世纪之前一直很稳定... 详细信息

根据对柱样沉积物^(21’)Pb定年及有机碳、硫和有机碳同位素含量分析,研究万泉河口沉积环境演变。硫和δ^(13)C均自19世纪初期开始持续减少,硫从1.92％逐渐减少到0.36％,δ^(13)C从-20.63‰减少到-23.64‰。C/S比在20世纪之前一直很稳定,处于0.47～0.80之间,有机碳与硫呈正相关;在此之后,C/S比急剧增加,至表层为3.94,硫的含量与有机碳的增加没有相关关系。结果表明在19世纪之前万泉河口尚为开阔的海湾,处于正常海洋环境,未形成被沙坝围封的泻湖,海水能够直接出入。19世纪初期开始,随着玉带滩沙坝向北发育,河口逐渐被围拦成泻湖型,进入的海水量逐渐减少;在19与20世纪之交,水体已开始明显淡化,发展成为今天近乎淡水的泻湖。

关键词：海南岛万泉河口沉积环境有机碳同位素 C/S比淡水泻湖环境演变海洋沉积物

Leveraging ROtI map derived from Indonesian GNSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia

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Earth and Planetary Physics 2025年第1期9卷 101-116页

作者： Prayitno Abadi Ihsan N.Muafiry teguh N.Pratama Angga Y.Putra Suraina Gatot H.Pramono Sidik t.Wibowo febrylian f.Chabibi Umar A.Ahmad Wildan P.tresna Asnawi Research Center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia School of Electrical Engineering Telkom UniversityBandungIndonesia Directorate of Laboratory Management facilities and Science and technology Park Indonesian National Research and Innovation Agency(BRIN)PontianakIndonesia Geophysics Laboratory Master Program in PhysicsUniversitas Gadjah Mada(UGM)YogyakartaIndonesia Research Center for Space Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian Geospatial Information Agency(BIG) JakartaIndonesia Research Center for Photonics Indonesian National Research and Innovation Agency(BRIN)Tangerang SelatanIndonesia Department of Earth and Planetary Sciences Hokkaido UniversitySapporoJapan

this paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning *** by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude ***-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast *** provide a practical tool for EPB research,by sharing two-dimensional rate of total Electron Content(tEC)change index(ROtI)derived from this *** generate ROtI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific *** preliminary findings from the ROtI maps of Ina-CORS are ***,the Ina-CORS ROtI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther ***,we demonstrate that combined ROtI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East *** have demonstrated the combined ROtI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,*** observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities *** sharing ROtI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionosphe

关键词： Equatorial Plasma Bubble(EPB) GNSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of tEC change index(ROtI)map

Effects of 3 months of full-court and half-court street basketball training on health profile in untrained men

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Journal of Sport and Health Science 2018年第2期7卷 132-138页

作者： Morten B.Randers Marie Hagman Jonathan Brix Jesper f.Christensen Mogens t.pedersen Jens J.Nielsen Peter Krustrup Department of Sports Science and Clinical Biomechanies SDU Sport and Health Sciences Cluster (SHSC) University of Southern Denmark Odense 5230 Denmark Department of Nutrition Exercise and Sports University of Copenhagen Copenhagen 2200 Denmark Centre oflnflammation and Metabolism (CIM) and Centre for Physical Activity Research (CfAS) Rigshospitalet Faculty of Health Science Copenhagen University Hospital 7641 University of Copenhagen Copenhagen 2100 Denmark Sport and Health Sciences University of Exeter Exeter EX1 2LU UK

Purpose: the aim of the present study was to investigate whether street basketball organized as 3 v 3 on either a half court(HC) with 1 basket or a full court(fC) with 2 baskets could improve fitness and health profiles of untrained men after 3 months of supervised ***: thirty-five untrained men(aged 20—42 years) completed the pre-and post-intervention testing(fC: n = 13, HC: n = 12, CO(control):n = 10). the training attendance was 2.0 ± 0.4 and 1.9 ± 0.3 times per week in fC and HC, respectively. Mean heart rate(HR) was 83.8 ± 6.0 percent of maximal heart rate(%HR_(max)) and 84.5 ± 2.9 %HR_(max) in fC and HC, ***: the 3 months of street basketball training on an fC with 2 baskets increased maximal oxygen uptake(2.4 mL/min/kg(95% confidence interval(CI): 1.0—3.9)), time to exhaustion(47 s(95%CI: 26—67)), lean body mass(0.8 kg(95%CI: 0.1—1.5)), and bone mineral density(0.021 g/cm^2(95%CI: 0.011—0.031)), whereas mean arterial pressure(—5.6 mm Hg(95%CI: —7.5 to 3.7)), body fat percentage(—1.6%,(95%CI: —2.5 to —0.7)), heart rate(—18 bpm(95%CI: —24 to —12)), and blood lactate(median: —1.4 mmol/L(interquartile range: —1.5 to —0.6)) during submaximal running were lowered. the changes were less pronounced after the training period when playing on an HC with 1 basket, but increases in maximal oxygen uptake(1.6 mL/min/kg(95%CI: —0.1 to 3.3)), time to exhaustion(28 s(95%CI: 9—47)), lean body mass(1.3 kg(95%CI: 0.3—2.4)), and lower body fat percentage(—0.9%(95%CI: —1.9 to —0.1)) were observed in this ***: three months of 3 v 3 street basketball training improved fitness and led to broad-spectrum improvements in variables related to overall health profile, with the most marked effects observed when playing on an fC with 2 baskets.

关键词： Blood pressure Body composition Cardiovascular fitness Maximal oxygen uptake Muscoloskeletal fitness Physical demands Small-sided games team sport

On the Indeterminacy in Hardness of Shape Memory Alloys

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Journal of Materials Science & technology 2004年第6期20卷 700-702页

作者： f.t.Cheng DeDartment of Applied Phvsics

the present communication addresses an interesting problem related to the indeterminacy in hardness of superelastic Niti reported by Xu et al. the origin of the indeterminacy is attributed to the inadequacy of the conventional Vickers hardness testing measurement which does not record elastic deformation, and thus the indeterminacy may be removed with suitable techniques. Concepts of hardness in relation to deformation are clarified. Recommendations for measuring the hardness of Niti and other elastic-plastic materials are suggested, together with comments on the advantages and disadvantages of each of these methods.

关键词： Hardness Elastic-plastic materials Elastic recovery Vickers microhardness test Niti SMA

Application of transition metal isotope tracers in global change research

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Chinese Journal of Oceanology and Limnology 2005年第2期23卷 218-225页

作者：宋金明 thomas f.pedersen Marine Ecology and Environmental Science Lab Institute of Oceanology Chinese Academy of Sciences. Qingdao 266071China Department of Earth and Ocean Sciences University of British ColumbiaVancouverV6T 1Z4Canada

High-precision isotope composition determinations using multicollector, magnetic-sector induc- tively coupled plasma mass spectrometry (MC-ICPMS) have recently revealed that some transition metal isotopes such as those of Mo, fe, Cu, Zn etc. can be used as biogeochemical tracers in global change research. the Mo isotope system may be useful in paleoredox investigations indicating that δ97/95Mo in seawater may co-vary with changes in the relative proportions of anoxic and oxic sedimentation in the ocean, and that this variation may be recorded inδ97/95Mo of anoxic sediments. the Mo continental flux into the oceans and the global Mo isotope budget can be estimated fromδ97/95Mo values. the fe isotope composition in seawater is an important issue because fe plays a controlling role in biological productivity in the oceans and its abundance in seawater may have substantial effect on climate changes. Iron isotope fractionations could result from bio- and abio-processes and have about 0.1% variation (δ56/54fe), so fe isotopes considered alone cannot be used to distinguish the products of abiotic and biotic fe processing in geological records. Cu and Zn isotopes are also used as biogeochemical tracers, but the researches are relatively less. this review mainly focuses on the methods for preparation, purification and determination of new isotope tracer samples, and on isotope applications in marine environmental changes.

关键词： transition metal isotope biogeochemical tracers global change research

Structural,electronic,optical,and magnetic properties of Co-doped Cu2O

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Chinese Physics B 2017年第2期26卷 387-391页

作者： I Djabri t Rezkallah f Chemam Laboratoire de la Physique Appliquee et theorique Departement des Sciences de la matiere Universite Laarbi tebessi tebessa Algeri

We investigate the magnetic properties of Co-doped Cu_2O. We studied first the electronic and structural properties of Cu_2O using the optimization of the lattice constant which is 4.18 . the calculated gap is found between 0.825 eV and1.5 eV, these values are in good agreement with the experimental results. the Co atoms are inserted in Cu_2O by means of the density functional theory（Dft） using LSDA, LSDA ＋U, and LSDA ＋ MBJ approximations in the WIEN2 k code, based on the supercell model by setting up 12, 24, and 48 atoms in（1×1 × 2）,（1 × 2 × 2）, and（2 × 2×2） supercells respectively with one or two copper atoms being replaced by cobalt atoms. the energy difference between the ferromagnetic and antiferromagnetic coupling of the spins located on the substitute Co has been calculated in order to obtain better insight into the magnetic exchange coupling for this particular compound. the studied compound exhibits stable integer magnetic moments of 2 μBand 4 μBwhen it is doped with 2 atoms of Co. Optical properties have also been worked out. the results obtained in this study demonstrate the importance of the magnetic effect in Cu_2O.

关键词： Cu2O electronic structure magnetic properties optical properties

Determination and prediction of pavement skid resistance–connecting research and practice

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Journal of Road Engineering 2021年第1期1卷 43-62页

作者： t.f.fwa Department of Civil&Environmental Engineering National University of SingaporeSingapore 117576Singapore

Adequate pavement skid resistance is a key requirement for safe road ***,the measurement and prediction of the skid resistance property of an in-service road pavement,or pavement mixture specimens in the laboratory,is a highly challenging process from both theoretical and practical points of *** more than 60 years,owing to the lack of theoretical solutions to the complex tire-fluid-pavement interaction problem,the practice of pavement skid resistance determination and prediction has essentially been derived from experimental and field observed *** rapid development of efficient numerical computational techniques and high-power computing facilities in the last two decades made it possible for researchers to numerically solve the tire-fluidpavement interaction *** enables the numerical evaluation and prediction of high-speed wet skid resistance,and the determination of the tire-pavement kinetic friction coefficient in the evaluation of low-speed skid *** paper presents a state-of-the-art review of the research development of theoretical mechanistic approaches in the determination and prediction of pavement skid *** covers the following main aspects of the subject matter:(i)mechanisms of skid resistance generation in dry,wetted(i.e.,damp),wet and flooded pavements;(ii)theoretical evaluation of pavement skid resistance in dry,wetted,wet and flooded states;(iii)theoretical approaches in pavement skid resistance prediction;and(iv)concepts of representing the skid resistance state of *** capability of finite element simulation approach for wet skid resistance evaluation with good accuracy is *** highlighted is the practical significance of the Concept of Skid Resistance *** of practical applications of the concept,coupled with the simulation model,are *** include applications in driving safety analysis,road safety design and control,design of paving mixtures,safety mainte

关键词： Skid resistance tire-fluid-pavement interaction Coefficient of kinetic friction Microtexture Macrotexture Pavement friction management

Electromembrane extraction–Recent trends and where to go

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Journal of Pharmaceutical Analysis 2017年第3期7卷 141-147页

作者： Stig pedersen-Bjergaard Chuixiu Huang Astrid Gjelstad School of Pharmacy University of Oslo faculty of Health and Medical Sciences School of Pharmaceutical Sciences University of Copenhagen

Electromembrane extraction(EME) is an analytical microextraction technique, where charged analytes(such as drug substances) are extracted from an aqueous sample(such as a biological fluid), through a supported liquid membrane(SLM) comprising a water immiscible organic solvent, and into an aqueous acceptor solution. the driving force for the extraction is an electrical potential(dc) applied across the SLM. In this paper, EME is reviewed. first, the principle for EME is explained with focus on extraction of cationic and anionic analytes, and typical performance data are presented. Second, papers published in 2016 are reviewed and discussed with focus on(a) new SLMs,(b) new support materials for the SLM,(c) new sample additives improving extraction,(d) new technical configurations,(e) improved theoretical understanding, and(f) pharmaceutical new applications. finally, important future research objectives and directions are defined for further development of EME, with the aim of establishing EME in the toolbox of future analytical laboratories.

关键词： Sample preparation Microextraction Electromembrane extraction