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NEAR'S CLOSE fLYBY Of C-TYPE ASTEROID 253 MATHILDE

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紫金山天文台台刊 1998年第2期 44-50页

作者： james f.bell iii the NEAR Science Team Cornell University Department of Astronomy Ithaca NY 14853-6801 USA

On June 27, 1997, the Near Earth Asteroid Rendezvous (NEAR) spacecraft flew within 1200km of the main belt asteroid 253 Mathilde. Previous observations of Mathilde had revealed it to be a C-type asteroid with an astonishingly-long rotation period of 17.4 days, an albedo of 3.8%, and a mean diameter of 60 km. Observations by NEAR reveal that Mathilde has a roughly triaxial shape of 66 × 48 × 46 km diameter and a mass of 1. 02 × 10 g, implying a mean density of only 1. 3g/cm3 . The surface of Mathilde was observed to be saturated with large impact craters, showing a range of visible topography in excess of 5 km. Multispectral observations did not reveal any substantial color differences across the surface, and coverage at multiple phase angles was used to derive a preliminary albedo of 3. 5 % to 5% .The low observed density, lack of color variations, and low albedo all suggest that Mathilde may be a primitive, carbon - rich object with an interior that contains substantial pore space.

关键词：小行星飞船紫金山天文台探测

PRELIMINARY SCIENCE RESULTS fROM THE MARS PATHfINDER MISSION

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紫金山天文台台刊 1998年第2期 22-32页

作者： james f.bell iii Nicolas Thomas the Mars Pathfinder Science Team Cornell University Department of Astronomy Ithaca NY 14853-6801 USAMax Planck Institute für Aeronomie D-37189 Katlenberg-Lindau Germany

The NASA Mars Pathfinder mission successfully carried out the first robotic exploration of the Martian surface since the Viking Lander missions of the late 1970s. The mission is one of the new "Discovery class"spacecraft designed t0 demonstrate the concepts of low cost, rapid development, innovative technology, and small science and operational teams. Pathfinder landed on Mars on July 4, 1997 near 19°N, 33°W, at the mouth of an ancient outflow channel. The mission operated for 83 days on the Martian surface, returning thousands of multispectral images, millions of meteorological measurements, chemical analyses of nearly 20 rock and soil samples, and data from a number of other engineering and technology experiments. Key scientific results from the initial analyses of the compositional and mineralogic data returned include: (1)Evidence that some rocks at the landing site may have higher Si content than"typical"terrestrial basalts or the SNC meteorites, possibly implying a greater degree of crustal

关键词：初步成果火星探测器天文台紫金山宋本

Bolstering integrity in environmental data science and machine learning requires understanding socioecological inequity

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frontiers of Environmental Science & Engineering 2024年第5期18卷 171-179页

作者： Joe f.Bozeman iii School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA30332USA School of Public Policy Georgia Institute of TechnologyAtlantaGA30332USA

Socioecological inequity in environmental data science—such as inequities deriving from data-driven approaches and machine learning(ML)—are current issues subject to debate and *** is growing consensus around embedding equity throughout all research and design domains—from inception to administration,while also addressing procedural,distributive,and recognitional ***,practically doing so may seem onerous or daunting to *** current perspective helps to alleviate these types of concerns by providing substantiation for the connection between environmental data science and socioecological inequity,using the Systemic Equity framework,and provides the foundation for a paradigmatic shift toward normalizing the use of equity-centered approaches in environmental data science and ML *** the integrity of environmental data science and ML is just beginning from an equity-centered tool development and rigorous application *** this end,this perspective also provides relevant future directions and challenges by overviewing some meaningful tools and strategies—such as applying the Wells-Du Bois Protocol,employing fairness metrics,and systematically addressing irreproducibility;emerging needs and proposals—such as addressing data-proxy bias and supporting convergence research;and establishes a ten-step path ***,the work that environmental scientists and engineers do ultimately affect the well-being of us all.

关键词： Equity Bias Machine Learning Data Science Justice Systemic Equity

Commentary on“Incidence of urinary incontinence following endoscopic laser enucleation of the prostate by en-bloc and non-en-bloc techniques:a multicenter,real-world experience of 5068 patients”

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Asian Journal of Andrology 2024年第3期26卷 333-334页

作者： james f Jiang Narmina K Onder Akhil K Das Department of Urology University of California Irvine Orange CA 92868 USA.

Laser enucleation of the prostate is a proven and effectivesize-independent method for the surgical management of symptomaticbenign prostatic hyperplasia(BPH)and is considered as the“goldstandard”by many *** major hurdles that stand in theway of this becoming a universally used procedure for BPH are thesteep learning curve associated with mastering the procedure andpossibility of perioperative transient *** advances inteaching methodologies have helped tackle the difficulty in learning itand increased the number of urologists utilizing the *** forthe second hurdle,transient incontinence rates postlaser enucleationof the prostate have improved with the advent of newer techniques *** et al.1 assesses the incidence of stress,urge,andmixed urinary incontinence following laser enucleation of the prostateby comparing en-bloc and non-en-bloc techniques in a multicenterseries of 5068 men with BPH.

关键词： urinary incontinence transient

Nickel sulfate solution fluoride separation with hydrous zirconium oxide

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Tungsten 2024年第2期6卷 367-381页

作者： Elbert M.Nigri Ummul K.Sultana André L.A.Santos james W.Vaughan Sonia D.f.Rocha Department of Mining Engineering Federal University of Minas GeraisBelo Horizonte 31270-901Brazil School of Chemical Engineering University of QueenslandSt Lucia 4072Australia

fluoride is an impurity in nickel sulfate production,which is required for electric vehicle *** zirconium oxide(HZO)was evaluated for removing fl uoride from nickel sulfate *** fluoride removal occurred at pH value 4 and optimal pH value is 4–5,considering Zr *** availability decreases with pH due to hydrogen fluoride and zirconium fluoride aqueous *** removal is initially rapid,with 50 wt.%removal in 7 min,followed by slow removal up to 68 wt.%after 72 h and follows second order rate *** removal was dominated by an ion exchange mechanism and resulting Zr–f bonds were observed using fourier-transform infrared *** presence of nickel sulfate decreased loading capacity compared to a salt-free *** maintained adsorption capacity through five cycles of loading and regeneration.

关键词： Hydrous zirconium oxide Nickel sulfate fluoride Adsorption Anion exchange

理解老年人的身体活动:基于时空行为视角的研究

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体育科学 2024年第1期44卷 78-87页

作者：成佳俐仇军 james f.Sallis 于洪军河北师范大学公共体育教学部河北石家庄050024 湖州师范学院体育与大健康研究院浙江湖州313000 美国加州大学圣地亚哥分校家庭医学与公共卫生系加利福尼亚圣地亚哥92093 清华大学体育部北京100084

目的:从时空行为视角对建成环境与老年人户外身体活动的时空行为特征进行研究,为促进我国老年人身体活动水平提升和应对老龄化趋势提供新思路。方法:采用全球定位系统(global position system,GPS)和三维加速度计对126名老年人时空行为... 详细信息

目的:从时空行为视角对建成环境与老年人户外身体活动的时空行为特征进行研究,为促进我国老年人身体活动水平提升和应对老龄化趋势提供新思路。方法:采用全球定位系统(global position system,GPS)和三维加速度计对126名老年人时空行为数据进行同步收集,通过空间算法将环境暴露数据与身体活动数据相关联,总结其出行方式、出行时间、出行频率、出行范围等特征。结果:1)老年人户外身体活动存在“点-线”型、“候鸟”型、“条链”型、“自由”型、“邻里”型、“综合”型6种时空模式;2)老年人主要户外身体活动范围为家附近500 m左右;3)老年人近45%的热量消耗和中高强度身体活动发生在户外空间,主要户外活动兴趣点为休闲娱乐、购物和运动健身;4)老年人户外身体活动特征以出行频率高和短时耗为主,出行次数对身体活动水平有显著影响,出行次数每增加1次,平均每周户外身体活动水平增加20.5 min。结论:我国老年人户外身体活动呈现出多样化的时空行为模式,未来可以将增加出行次数作为促进老年人身体活动水平的切入点。

关键词：时空行为建成环境老年人户外身体活动

Uncovering the dominant contribution of intermediate volatility compounds in secondary organic aerosol formation from biomass-burning emissions

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National Science Review 2024年第3期11卷 150-158页

作者： Kun Li Jun Zhang David M.bell Tiantian Wang Houssni Lamkaddam Tianqu Cui Lu Qi Mihnea Surdu Dongyu Wang Lin Du Imad El Haddad Jay G.Slowik Andre S.H.Prevot Environment Research Institute Shandong University Laboratory of Atmospheric Chemistry Paul Scherrer Institute

Organic vapors from biomass burning are a major source of secondary organic aerosols(SOAs). Previous smog chamber studies found that the SOA contributors in biomass-burning emissions are mainly volatile organic compounds(VOCs). While intermediate volatility organic compounds(IVOCs) are efficient SOA precursors and contribute a considerable fraction of biomass-burning emissions, their contribution to SOA formation has not been directly observed. Here, by deploying a newly-developed oxidation flow reactor to study SOA formation from wood burning, we find that IVOCs can contribute ～70% of the formed SOA, i.e.>2 times more than VOCs. This previously missing SOA fraction is interpreted to be due to the high wall losses of semi-volatile oxidation products of IVOCs in smog chambers. The finding in this study reveals that SOA production from biomass burning is much higher than previously thought, and highlights the urgent need for more research on the IVOCs from biomass burning and potentially other emission sources.

关键词： atmospheric chemistry biomass burning secondary organic aerosol intermediate volatility organic compounds

What diameter?What height?Influence of measures of average tree size on area-based allometric volume relationships

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forest Ecosystems 2024年第1期11卷 100-109页

作者： Yilin Wang John A.Kershaw Mark J.Ducey Yuan Sun james B.McCarter Integrated forest Mensuration and Systems Analysis Laboratory Faculty of Forestry and Environmental ManagementUniversity of New BrunswickFrederictonNBCanada Department of Natural Resources and the Environment University of New HampshireDurhamNHUSA College of forestry Nanjing Forestry UniversityNanjing210037China Scientific Programmer RayonierYuleeFLUSA

Volume is an important attribute used in many forest management *** from 83 fixed-area plots located in central New Brunswick,Canada,are used to examine how different measures of stand-level diameter and height influence volume prediction using a stand-level variant of Honer's(1967)volume *** density was included in the models(Volume=f(Diameter,Height,Density))choice of diameter measure was more important than choice of height *** density was not included(Volume=f(Diameter,Height)),the opposite was *** models with density included,moment-based estimators of stand diameter and height performed better than all other *** models without density,largest tree estimators of stand diameter and height performed better than other *** overall best equation used quadratic mean diameter,Lorey's height,and density(root mean square error=5.26 m^3·ha^(-1);1.9%relative error).The best equation without density used mean diameter of the largest trees needed to calculate a stand density index of 400 and the mean height of the tallest 400 trees per ha(root mean square error=32.08 m^(3)·ha^(-1);11.8%relative error).The results of this study have some important implications for height subsampling and LiDAR-derived forest inventory analyses.

关键词： Allometric relationships Stand structure Volume estimation Stand-level attributes

亚热带森林植物的叶片和根系功能性状部分耦合但具有不同的群落性状分布格局

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Journal of Plant Ecology 2024年第1期17卷 94-110页

作者： Wenqi Luo Oscar J Valverde-Barrantes Monique Weemstra james f Cahill Jr Zi Wang Dong He Yongfa Chen Chengjin Chu Youshi Wang State Key Laboratory of Biocontrol School of Life Sciences/School of EcologySun Yat-sen UniversityGuangzhou 510275China International Center for Tropical Botany Department of Biological SciencesFlorida International UniversityMiamiFL 33199USA Department of Biological Sciences University of AlbertaEdmontonABT6G 2E9Canada School of Ecology and the Environment Xinjiang UniversityUrumqi 830046China

植物的生态过程依赖于叶片和根系的功能运行,但少有研究同时关注这两类性状在群落中的分布格局(CTD)。本文测定了广东亚热带森林44种共生木本植物的16个叶片和根系性状,旨在检验类比的叶片和根系性状是否耦合,是否沿类似的功能性状谱变... 详细信息

植物的生态过程依赖于叶片和根系的功能运行,但少有研究同时关注这两类性状在群落中的分布格局(CTD)。本文测定了广东亚热带森林44种共生木本植物的16个叶片和根系性状,旨在检验类比的叶片和根系性状是否耦合,是否沿类似的功能性状谱变异,是否表现出类似的CTD,其CTD和群落加权平均性状值(CWM)是否沿环境梯度表现出类似的响应。研究结果表明,叶片和根系性状变异的第一轴均呈显出由资源获取向资源保守变异的经济学谱,但叶片变异的第二轴主要由叶片碳含量表征,而根系变异的第二轴主要由反映菌根协作程度的根系粗细表征。类比的叶片和根系化学性状整体正相关,但形态性状的耦合程度较低。在群落水平上,叶片和根系性状第一轴的CWM均随海拔升高而变得更保守,而第二轴的变化则不一致。随土壤磷含量的降低或钾含量的升高,根系变得更细和在养分性状上更保守,而叶片性状无显著变化。当整合多维性状轴时,叶片性状呈发散格局,且随海拔、土壤磷和钾含量的增加呈收敛趋势;而根系性状呈收敛格局,但沿上述环境梯度呈发散趋势。该研究强调,叶片和根系性状与环境互作的差异可能导致不同的性状分布格局;植物可通过多样的地上和地下功能设计应对环境异质性。

关键词：性状维度群落构建叶片性状根系性状植物经济谱群落性状结构亚热带森林