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Accurate compound-specific C-14 dating of archaeological pottery vessels 期刊论文
NATURE, 2020, 580 (7804) : 506-+
作者:  Yin, Yafei;  Lu, J. Yuyang;  Zhang, Xuechun;  Shao, Wen;  Xu, Yanhui;  Li, Pan;  Hong, Yantao;  Cui, Li;  Shan, Ge;  Tian, Bin;  Zhang, Qiangfeng Cliff;  Shen, Xiaohua
收藏  |  浏览/下载:20/0  |  提交时间:2020/05/13

Pottery is one of the most commonly recovered artefacts from archaeological sites. Despite more than a century of relative dating based on typology and seriation(1), accurate dating of pottery using the radiocarbon dating method has proven extremely challenging owing to the limited survival of organic temper and unreliability of visible residues(2-4). Here we report a method to directly date archaeological pottery based on accelerator mass spectrometry analysis of C-14 in absorbed food residues using palmitic (C-16:0) and stearic (C-18:0) fatty acids purified by preparative gas chromatography(5-8). We present accurate compound-specific radiocarbon determinations of lipids extracted from pottery vessels, which were rigorously evaluated by comparison with dendrochronological dates(9,10) and inclusion in site and regional chronologies that contained previously determined radiocarbon dates on other materials(11-15). Notably, the compound-specific dates from each of the C-16:0 and C-18:0 fatty acids in pottery vessels provide an internal quality control of the results(6) and are entirely compatible with dates for other commonly dated materials. Accurate radiocarbon dating of pottery vessels can reveal: (1) the period of use of pottery  (2) the antiquity of organic residues, including when specific foodstuffs were exploited  (3) the chronology of sites in the absence of traditionally datable materials  and (4) direct verification of pottery typochronologies. Here we used the method to date the exploitation of dairy and carcass products in Neolithic vessels from Britain, Anatolia, central and western Europe, and Saharan Africa.


Using lipid residues absorbed in potsherds, the ages of pottery from various archaeological sites are determined and validated using sites for which the dates are well known from other methods.


  
Redox-switchable carboranes for uranium capture and release 期刊论文
NATURE, 2020, 577 (7792) : 652-+
作者:  Marques, Joao C.;  Li, Meng;  Schaak, Diane;  Robson, Drew N.;  Li, Jennifer M.
收藏  |  浏览/下载:31/0  |  提交时间:2020/07/03

The uranyl ion (UO22+  U(vi) oxidation state) is the most common form of uranium found in terrestrial and aquatic environments and is a central component in nuclear fuel processing and waste remediation efforts. Uranyl capture from either seawater or nuclear waste has been well studied and typically relies on extremely strong chelating/binding affinities to UO22+ using chelating polymers(1,2), porous inorganic(3-5) or carbon-based(6,7) materials, as well as homogeneous(8) compounds. By contrast, the controlled release of uranyl after capture is less established and can be difficult, expensive or destructive to the initial material(2,9). Here we show how harnessing the redox-switchable chelating and donating properties of an ortho-substituted closo-carborane (1,2-(Ph2PO)(2)-1,2-C2B10H10) cluster molecule can lead to the controlled chemical or electrochemical capture and release of UO22+ in monophasic (organic) or biphasic (organic/aqueous) model solvent systems. This is achieved by taking advantage of the increase in the ligand bite angle when the closo-carborane is reduced to the nido-carborane, resulting in C-C bond rupture and cage opening. The use of electrochemical methods for uranyl capture and release may complement existing sorbent and processing systems.


Redox-switchable chelation is demonstrated for a carborane cluster molecule, leading to controlled chemical or electrochemical capture and release of uranyl in monophasic or biphasic model solvent systems.


  
Beneficial land use change: Strategic expansion of new biomass plantations can reduce environmental impacts from EU agriculture 期刊论文
GLOBAL ENVIRONMENTAL CHANGE-HUMAN AND POLICY DIMENSIONS, 2020, 60
作者:  Englund, Oskar;  Borjesson, Pal;  Berndes, Goran;  Scarlat, Nicolae;  Dallemand, Jean-Francois;  Grizzetti, Bruna;  Dimitriou, Ioannis;  Mola-Yudego, Blas;  Fahl, Fernando
收藏  |  浏览/下载:11/0  |  提交时间:2020/07/02
Land use  LUC  Biomass  Environmental impacts  Ecosystem services  Perennial crops  
Transformational adaptation on the farm: Processes of change and persistence in transitions to 'climate-smart' regenerative agriculture 期刊论文
GLOBAL ENVIRONMENTAL CHANGE-HUMAN AND POLICY DIMENSIONS, 2019, 59
作者:  Gosnell, Hannah;  Gill, Nicholas;  Voyer, Michelle
收藏  |  浏览/下载:10/0  |  提交时间:2020/02/17
Climate change adaptation and mitigation  Holistic Management  Transformative learning  Communities of practice  Earth stewardship  Relational thinking  
Public perceptions of how to reduce carbon footprints of consumer food choices 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2019, 14 (11)
作者:  Kause, Astrid;  de Bruin, Waendi Bruine;  Millward-Hopkins, Joel;  Olsson, Henrik
收藏  |  浏览/下载:6/0  |  提交时间:2019/11/27
food  behavior change  communication  carbon footprint  climate  
Comment on "The global tree restoration potential" 期刊论文
SCIENCE, 2019, 366 (6463)
作者:  Veldman, Joseph W.;  Aleman, Julie C.;  Alvarado, Swanni T.;  Anderson, T. Michael;  Archibald, Sally;  Bond, William J.;  Boutton, Thomas W.;  Buchmann, Nina;  Buisson, Elise;  Canadell, Josep G.;  Dechoum, Michele de Sa;  Diaz-Toribio, Milton H.;  Durigan, Giselda;  Ewel, John J.;  Fernandes, G. Wilson;  Fidelis, Alessandra;  Fleischman, Forrest;  Good, Stephen P.;  Griffith, Daniel M.;  Hermann, Julia-Maria;  Hoffmann, William A.;  Le Stradic, Soizig;  Lehmann, Caroline E. R.;  Mahy, Gregory;  Nerlekar, Ashish N.;  Nippert, Jesse B.;  Noss, Reed F.;  Osborne, Colin P.;  Overbeck, Gerhard E.;  Parr, Catherine L.;  Pausas, Juli G.;  Pennington, R. Toby;  Perring, Michael P.;  Putz, Francis E.;  Ratnam, Jayashree;  Sankaran, Mahesh;  Schmidt, Isabel B.;  Schmitt, Christine B.;  Silveira, Fernando A. O.;  Staver, A. Carla;  Stevens, Nicola;  Still, Christopher J.;  Stromberg, Caroline A. E.;  Temperton, Vicky M.;  Varner, J. Morgan;  Zaloumis, Nicholas P.
收藏  |  浏览/下载:17/0  |  提交时间:2019/11/27
Carbon emissions from cropland expansion in the United States 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2019, 14 (4)
作者:  Spawn, Seth A.;  Lark, Tyler J.;  Gibbs, Holly K.
收藏  |  浏览/下载:8/0  |  提交时间:2019/11/26
land use change  grassland  carbon emissions  biofuels  United States  agriculture  soil organic carbon  
Impacts of forests and forestation on hydrological services in the Andes: A systematic review 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2019, 433: 569-584
作者:  Bonnesoeur, Vivien;  Locatelli, Bruno;  Guariguata, Manuel R.;  Ochoa-Tocachi, Boris F.;  Vanacker, Veerle;  Mao, Zhun;  Stokes, Alexia;  Mathez-Stiefel, Sarah-Lan
收藏  |  浏览/下载:9/0  |  提交时间:2019/04/09
Comment on "Unexpected reversal of C-3 versus C-4 grass response to elevated CO2 during a 20-year field experiment" 期刊论文
SCIENCE, 2018, 361 (6402)
作者:  Wolf, Julie;  Ziska, Lewis
收藏  |  浏览/下载:6/0  |  提交时间:2019/11/27
Do private coffee standards 'walk the talk' in improving socio-economic and environmental sustainability? 期刊论文
GLOBAL ENVIRONMENTAL CHANGE-HUMAN AND POLICY DIMENSIONS, 2018, 51: 1-9
作者:  Vanderhaegen, Koen;  Akoyi, Kevin Teopista;  Dekoninck, Wouter;  Jocque, Rudy;  Muys, Bart;  Verbist, Bruno;  Maertens, Miet
收藏  |  浏览/下载:8/0  |  提交时间:2019/04/09
Food standards  Private food standards  Coffee certification  Sustainability  Sustainable agriculture  Sustainable food production  Sustainable food consumption  Biodiversity  Carbon storage  Agricultural productivity  Poverty  Rural development  Africa