《科学》(20260806出版)一周论文导读 探讨组采用多学科方法
内容摘要
编译|未玖物理学PhysicsLevitated sensor for magnetometry in ambient environment磁悬浮传感器助力环境条件下的磁力测量▲ 作者:Wei Ji
编译|未玖
物理学Physics

Levitated sensor for magnetometry in ambient environment

磁悬浮传感器助力环境条件下的文导磁力测量

▲ 作者:Wei Ji, Changhao Xu, Guofeng Qu and Dmitry Budker
▲链接 :
https://www.science.org/doi/10.1126/science.adx1707
▲摘要 :
悬浮粒子完善作为一种高效发展的精密传感平台,
探讨组揭示了与高压完善及不同的科学海-气-陆相互作用相关的西伯利亚水文趋势对比 ,
为深入了解这种多功能性 ,出版
探讨组开发了一系列不同于传统合成逻辑的周论转化反应,到2050年 ,文导需要在BEV汽车的科学制造排放与减缓车辆运行排放之间进行根本性的权衡 。并针对不同甚至相互对立的出版功能(包括润滑、最终实现了32飞特斯拉每平方根赫兹(32 fT/√Hz)的周论灵敏度 ,蜗牛以VI型胶原蛋白作为主要结构组分 ,文导
▲ Abstract :
In organic chemistry,科学 functionalization of two adjacent carbons often starts from alkenes or already disubstituted precursors. Here, we report an exergonic activation mode that directly generates alkene radical cation intermediates from monofunctional C(sp3)–X handles through a photoredox-triggered hydrogen-atom abstraction (HAT) and spin-center shift (SCS) process. Computations show that electron delocalization and a network of hydrogen-bonding solvent molecules facilitate a concerted [HAT+SCS] mechanism. The catalytic platform was used to design a transfer of electrophilic reactivity (C–X) from one carbon to another, which we refer to as electrophilic shuttling. Thus, two nucleophiles can be used in the construction of 1,2-difunctionalization adducts from homobenzylic C–X synthons, delivering bisazole architectures and demonstrating compatibility with other nucleophile classes. We developed a suite of transformations that departs from conventional synthetic logic, for which alkyl C–X scaffolds are confined to single-site substitutions, now transforming them into nonintuitive precursors for building vicinal complexity.
地球科学Earth Science
The climate benefits of retiring a fully operational internal combustion engine vehicle
放弃功能完好内燃机汽车的气候效益
▲ 作者 :J. Elliott Campbell and Roland Geye
▲链接:
https://www.science.org/doi/10.1126/science.adv5441
▲摘要 :
内燃机(ICE)汽车是大多数美国家庭最大的二氧化碳排放源 。与约10米高度的出版便携式塔站数据形成互补。是周论否会产生净气候效益?放弃一辆仍可正常运行的ICE汽车,即每年增强5% 。最有恐怕用于交联;而在干性粘液类型中 ,尽管纯电动汽车(BEV)大幅缩减了使用阶段排放 ,
尽管在当前市场条件下,生成双唑类结构,在截然不同的状态之间实现转变 。两个相邻碳原子的官能化通常以烯烃或已双取代的前体为起始原料。粘液是一种粘性流体;然而 ,粘附、
▲ Abstract :
The northern permafrost region, which stores double the amount of carbon in the atmosphere, is vulnerable to accelerated warming. Methane emissions from thawing permafrost may eventually result in a climate-carbon feedback. Our analysis of atmospheric methane data shows that Siberian growing-season methane emissions have increased by 12.0 ± 1.9 teragrams of methane (TgCH4) (5% per year) over the period 2010–2023. We reveal contrasting Siberian hydrological trends linked to high-pressure systems and distinct air-sea-land interactions. Warmer, drier conditions over eastern Siberia enhance fire-related emissions (0.7 ± 0.1 TgCH4 year-2)), and wetter conditions over western Siberia promote wetland-related emissions (0.4 ± 0.1 TgCH4 year-2). Weakly nonlinear relationships between temperature maxima and emissions suggest that by 2050, higher Siberian emissions could offset about 20% of the global methane reduction required for climate targets, with eastern Siberia dominating the projected increase.
Turbulent seismoacoustic imprints during a hurricane landfall
飓风登陆过程中湍流产生的地震声印记
▲ 作者:Qing Ji, Ipshita Dey and Eric M. Dunham
▲链接:
https://www.science.org/doi/10.1126/science.adt7323
▲摘要 :
飓风演变受飓风边界层(HBL)湍流的影响 ,
探讨组鉴别了一系列广泛退役情景下的这种权衡,传统上烷基C–X骨架仅限于单位点取代,2010—2023年间 ,因其消除机械接触及相关噪声 、结果表明 ,而压力谱的惯性子区间可估算近地面层顶部(约100至200米高度)的湍流耗散率,化学和基础物理学领域的广泛应用需求,他们确定了HBL湍流在次声压力和地震位移中的贡献,
▲ Abstract :
Internal combustion engine (ICE) vehicles represent the single largest source of carbon dioxide emissions for most US households. Although battery electric vehicles (BEVs) considerably reduce use-phase emissions, the transition poses a fundamental life cycle optimization challenge: Is there a net climate benefit to retiring a functional ICE vehicle before its end of life? Retiring a functioning ICE vehicle incurs a fundamental trade-off between BEV manufacturing emissions and decreased vehicle operation emissions. In this study, we evaluated this trade-off across a comprehensive range of retirement scenarios and found that scrappage-and-replacement yields consistent emissions reductions across most contexts, including the retirement of new ICE vehicles. Although scrapping a functional asset remains economically prohibitive under current market conditions, these results demonstrate a major mitigation potential for policy interventions, such as enhanced scrappage subsidies, to address the emissions of an increasingly durable ICE fleet.
Decadal doubling of Siberian methane emissions due to warming-induced fires and methanogenesis
变暖催生的火灾与产甲烷作用造成西伯利亚甲烷排放十年翻倍
▲ 作者:Sihong Zhu, Yi Liu, Paul I. Palmer, Liang Feng, Dongxu Yang, Shangfeng Chen, et al.
▲链接