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Mafic Archean continental crust prohibited exhumation of orogenic UHP eclogite

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Geoscience Frontiers 2021年第5期12卷 411-420页

作者： richard M.Palin James D.P.Moore Zeming Zhang Guangyu Huang Jon Wade Brendan Dyck Department of Earth Sciences University of OxfordOxford OX13ANUnited Kingdom Earth Observatory of Singapore Nanyang Technological UniversitySingapore Institute of Geophysics SGEESVictoria University of WellingtonWellingtonNew Zealand Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Department of Earth Environmental and Geographical SciencesUniversity of British ColumbiaKelowna V1V 1V7Canada

The absence of ultrahigh pressure(UHP)orogenic eclogite in the geological record older than c.0.6 Ga is problematic for evidence of subduction having begun on Earth during the Archean(4.0-2.5 Ga).Many eclogites in Phanerozoic and Proterozoic terranes occur as mafic boudins encased within low-density felsic crust,which provides positive buoyancy during subduction;however,recent geochemical proxy analysis shows that Archean continental crust was more mafic than previously thought,having greater proportions of basalt and komatiite than modern-day ***,we show via petrological modelling that secular change in the petrology and bulk composition of upper continental crust would make Archean continental terranes negatively buoyant in the mantle before reaching UHP *** or delaminated Archean continental crust passes a point of no return during metamorphism in the mantle prior to the stabilization of coesite,while Proterozoic and Phanerozoic terranes remain positively buoyant at these *** orogenic eclogite may thus readily have formed on the Archean Earth,but could not have been exhumed,weakening arguments for a Neoproterozoic onset of subduction and plate ***,isostatic balance calculations for more mafic Archean continents indicate that the early Earth was covered by a global ocean over 1 km deep,corroborating independent isotopic evidence for large-scale emergence of the continents no earlier than c.3 *** findings thus weaken arguments that early life on Earth likely emerged in shallow subaerial ponds,and instead support hypotheses involving development at hydrothermal vents in the deep ocean.

关键词： Archean Eclogite Exhumation Secular change Geodynamics Density

太阳辐射与冰盖/CO^(2)驱动晚上新世暖期中国北方降水

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Science Bulletin 2021年第4期66卷 319-322,M0003页

作者：罗增聂军胜 Annelisa Ehret Moe richard v.Heermance Carmala Garzione Timothy D.Herbert 王钊李华张蕊赵向明 Ulrich Salzmann Key Laboratory of Western China's Environment System(Ministry of Education) Lanzhou UniversityLanzhou 730000China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China Department of Geological Sciences California State UniversityNorthridge 91330-8266USA Department of Environmental Sciences Rochester Institute of TechnologyRochester 14623USA Department of Earth Environmentaland Planetary SciencesBrown UniversityProvidence 02912USA Department of Chemistry Lanzhou UniversityLanzhou 730000China School of Geography Geomatics and PlanningJiangsu Normal UniversityXuzhou 221116China Department of Geography and Environmental Sciences Northumbria UniversityNewcastle Upon Tyne NE18STUK

理解未来东亚夏季风的变化要求查明地质历史时期中的气候温暖阶段东亚夏季风的变化及驱动机制.黄土高原的风成沉积序列是研究过去东亚季风变化的良好载体,对第四纪期间沉积的记录研究表明东亚夏季风在此期间可能主要受冰盖、CO_(2)和太... 详细信息

理解未来东亚夏季风的变化要求查明地质历史时期中的气候温暖阶段东亚夏季风的变化及驱动机制.黄土高原的风成沉积序列是研究过去东亚季风变化的良好载体,对第四纪期间沉积的记录研究表明东亚夏季风在此期间可能主要受冰盖、CO_(2)和太阳辐射的共同驱动.晚上新世暖期(3.264~3.025 Ma)是距今最近的气候持续温暖时期,然而黄土高原红黏土记录却显示了较弱的轨道周期,与气候模拟结果不一致.为了解决这一矛盾,本文利用一个新的季风降水代用指标,重建了晚上新世暖期东亚季风的降水变化.结果表明东亚季风降水变化在该时期以2万年周期为主,说明太阳辐射是重要的驱动力,加深了我们对东亚夏季风在暖期变化及规律的认识.此外,我们还发现季风降水的4万年周期与南半球冰量的变化呈同相位关系,说明CO_(2)/南极冰盖也可能是驱动中国北方降水的因素.

关键词：太阳辐射南极冰盖暖期气候模拟轨道周期相位关系地质历史时期代用指标

Early transmission dynamics of COvID-19 in a southern hemisphere setting:Lima-Peru:February 29^(th)-March 30^(th),2020

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Infectious Disease Modelling 2020年第1期5卷 338-345页

作者： César v.Munayco Amna Tariq richard Rothenberg Gabriela G.Soto-Cabezas Mary F.Reyes Andree valle Leonardo Rojas-Mezarina César Cabezas Manuel Loayza Gerardo Chowell 无 Centro Nacional de Epidemiología Prevencion y Control de EnfermedadesPeruvian Ministry of HealthLimaPeru Department of Population Health Sciences School of Public HealthGeorgia State UniversityAtlantaGAUSA Instituto Nacional de Salud Peruvian Ministry of HealthLimaPeru Peru COvID-19 working group

The COvID-19 pandemic that emerged in Wuhan China has generated substantial morbidity and mortality impact around the world during the last four *** daily trend in reported cases has been rapidly rising in Latin America since March 2020 with the great majority of the cases reported in Brazil followed by Peru as of April 15th,*** Peru implemented a range of social distancing measures soon after the confirmation of its first case on March 6th,2020,the daily number of new COvID-19 cases continues to accumulate in this *** assessed the early COvID-19 transmission dynamics and the effect of social distancing interventions in Lima,*** estimated the reproduction number,R,during the early transmission phase in Lima from the daily series of imported and autochthonous cases by the date of symptoms onset as of March 30th,*** also assessed the effect of social distancing interventions in Lima by generating short-term forecasts grounded on the early transmission dynamics before interventions were put in *** to the implementation of the social distancing measures in Lima,the local incidence curve by the date of symptoms onset displays near exponential growth dynamics with the mean scaling of growth parameter,p,estimated at 0.96(95%CI:0.87,1.0)and the reproduction number at 2.3(95%CI:2.0,2.5).Our analysis indicates that school closures and other social distancing interventions have helped slow down the spread of the novel coronavirus,with the nearly exponential growth trend shifting to an approximately linear growth trend soon after the broad scale social distancing interventions were put in place by the *** the interventions appear to have slowed the transmission rate in Lima,the number of new COvID-19 cases continue to accumulate,highlighting the need to strengthen social distancing and active case finding efforts to mitigate disease transmission in the region.

关键词： COvID-19 SARS-Cov-2 Transmission potential Short-term forecast Reproduction number Generalized growth model

Spontaneous Twist and Intrinsic Instabilities of Pristine Graphene Nanoribbons

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Nano Research 2009年第2期2卷 161-166页

作者： Ksenia v.Bets Boris I.Yakobson Department of Mechanical Engineering&Materials Science Department of Chemistryand The Richard E.Smalley Institute for Nanoscale Science and TechnologyRice UniversityHoustonTexas 77005USA

In pristine graphene ribbons,disruption of the aromatic bond network results in depopulation of covalent orbitals and tends to elongate the edge,with an effective force of fe~2 ev/Å(larger for armchair edges than for zigzag edges,according to calculations).This force can have quite striking macroscopic manifestations in the case of narrow ribbons,as it favors their spontaneous twisting,resulting in the parallel edges forming a double helix,resembling DNA,with a pitchλt of about 1520 lattice *** atomistic simulations,we investigate how the torsionτ~1/λt decreases with the width of the ribbon,and observe its bifurcation:the twist of wider ribbons abruptly vanishes and instead the corrugation localizes near the *** length-scale(λe)of the emerging sinusoidal“frill”at the edge is fully determined by the intrinsic parameters of graphene,namely its bending stiffness D=1.5 ev and the edge force fe withλe~D/*** reveals other warping configurations and suggests their sensitivity to the chemical passivation of the edges,leading to possible applications in sensors.

关键词： Graphene nanoribbons mechanics twist

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开发软件包

个人电脑 1998年第5期4卷 151-175页

作者： richard v.Dragan 徐鹏

设计出一种可以在各种环境中运行的应用程序,这对于众多开发人员是一个不可抵御的诱惑。我们所考察的最优秀的软件包由于具有可视化工具和企业级功能,从而提供了对Java语言最新的扩展功能的支持。

关键词： Java语言软件开发软件包

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从头起步的Web数据库开发工具

个人电脑 1998年第1期4卷 147-166页

作者： richard v.Dragan 徐鹏

为您公司现有的客户/服务器数据库注入新的生命力。利用以下这六种套装软件中的一种建构一个基于Web的应用程序。

关键词： Web数据库应用程序开发工具基于Web 客户/服务器软件套装建构生命力起步

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OWL与MFC:类之争

个人电脑 1995年第7期1卷 97-99页

作者： richard v.Dragan

OS/2或Microsoft Windows应用框架其实就是封装和抽象API关键部分的C++类库。Borland C++4.5和Database Tools与Object Windows Library(OWL)2.5一起销售,而Microsoft visual C++ 2.0则突出了Microsoft Foundation Classes(MFC) 3.0。(Microsoft的16位visual C++ 1.51仍与老的MFC 2.5一起销售。) 这两个应用框架加快了Windows程序的开发,并使你能增加诸如OLE 2.0这样的功能,这些功能可以使你几乎不用自己编码。

关键词：编译器 C++类内联应用框架链接器第三方 ANSIC 应用程序名字空间 C++异常

A bio-inspired O2-tolerant catalytic CO2 reduction electrode

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Science Bulletin 2019年第24期64卷 1890-1895页

作者： Xu Lu Zhan Jiang Xiaolei Yuan Yueshen Wu richard Malpass-Evans Yiren Zhong Yongye Liang Neil BMcKeown Hailiang Wang Department of Chemistry Yale UniversityNew HavenCT 06520USA Energy Sciences Institute Yale UniversityWest HavenCT 06516USA Department of Materials Science and Engineering Shenzhen Key Laboratory of Printed Organic ElectronicsSouthern University of Science and TechnologyShenzhen 518055China Institute of Functional Nano and Soft Materials Jiangsu Key Laboratory for Carbon-Based Functional Materiab and DevicesSoochow UniversitySuzhou 215123China EastChem School of ChemistryUniversity of EdinburghEdinburgh EH93FJUK

The electrochemical reduction of CO2 to give CO in the presence of O2 would allow the direct valorization of flue gases from fossil fuel combustion and of CO2 captured from air. However, it is a challenging task because O2 reduction is thermodynamically favored over that of CO2. 5% O2 in CO2 near catalyst surface is sufficient to completely inhibit the CO2 reduction reaction. Here we report an O2-tolerant catalytic CO2 reduction electrode inspired by part of the natural photosynthesis unit. The electrode comprises of heterogenized cobalt phthalocyanine molecules serving as the cathode catalyst with >95% Faradaic efficiency(FE) for CO2 reduction to CO coated with a polymer of intrinsic microporosity that works as a CO2-selective layer with a CO2/O2 selectivity of $20. Integrated into a flow electrolytic cell, the hybrid electrode operating with a CO2 feed gas containing 5% O2 exhibits a FECOof 75.9% with a total current density of 27.3 mA/cm^2 at a cell voltage of 3.1 v. A FECO of 49.7% can be retained when the O2 fraction increases to 20%. Stable operation for 18 h is demonstrated. The electrochemical performance and O2 tolerance can be further enhanced by introducing cyano and nitro substituents to the phthalocyanine ligand.

关键词： Electrochemical CO2 reduction O2 tolerance Gas separation Polymer of intrinsic microporosity Cooperative catalysis

Call for emergency action to limit global temperature increases, restore biodiversity and protect health

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World Journal of Pediatric Surgery 2021年第4期4卷 60-62页

作者： Lukoye Atwoli Abdullah H Baqui Thomas Benfield Raffaella Bosurgi Fiona Godlee Stephen Hancocks richard Horton Laurie Laybourn-Langton Carlos Augusto Monteiro Ian Norman Kirsten Patrick Nigel Praities Marcel GM Olde Rikkert Eric J Rubin Peush Sahni richard Smith Nicholas J Talley Sue Turale Damián vázquez East African Medical Journal NairobiKenya Journal of Health Population and NutritionBaltimoreMarylandUSA Danish Medical Journal CopenhagenDenmark PLOS Medicine CambridgeUK The BMJ LondonUK British Dental Journal LondonUK The Lancet LondonUK UK Health Alliance on Climate Change LondonUK Revista de Saúde Pública São PauloBrazil International Journal of Nursing Studies LondonUK CMAJ OttawaOntarioCanada Pharmaceutical Journal LondonUK Dutch Journal of Medicine NijmegenThe Netherlands NEJM BostonMassachusettsUSA National Medical Journal of India New DelhiIndia Medical Journal of Australia NewcastleNew South WalesAustralia International Nursing Review GenevaSwitzerland Pan American Journal of Public Health WashingtonDCUSA

Wealthy nations must do much more,much *** United Nations General Assembly in September 2021 will bring countries together at a critical time for marshalling collective action to tackle the global environmental *** will meet again at the biodiversity summit in Kunming,China,and the climate conference(Conference of the Parties(COP)26)in Glasgow,*** of these pivotal meetings,we-the editors of health journals worldwide-call for urgent action to keep average global temperature increases below 1.5℃,halt the destruction of nature and protect health.

关键词： action collective faster