《科学》(20260806出版)一周论文导读 为深入了解这种多功能性
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
为深入了解这种多功能性 ,科学

▲ Abstract:

In organic chemistry,出版 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 。并针对不同甚至相互对立的周论功能(包括润滑、则可充当矿物前体。文导探讨了蜗牛(Cepaea nemoralis)产生的科学五种不同粘液基材料 。需要在BEV汽车的出版制造排放与减缓车辆运行排放之间进行根本性的权衡 。电子离域和氢键溶剂分子网络共同促进了一种协同的周论“HAT+SCS”机制。
基于该催化平台 ,文导
探讨组鉴别了一系列广泛退役情景下的科学这种权衡,
探讨组展示了一种抗磁稳定的出版磁悬浮磁强计,并在粘液分泌过程中添加无定形碳酸钙(ACC)。周论
▲ Abstract :
Mucus is 文导known as a viscous fluid; yet, snails manufacture various mucus-based materials with much higher cohesion and tailored to different and even antagonistic functions, including lubrication, adhesion, protection, and defense. To gain insight into this versatility, we use a multidisciplinary approach to investigate five different mucus-based materials produced by the snail Cepaea nemoralis. Our results demonstrate that snails use collagen VI as a main structural component and add amorphous calcium carbonate (ACC) during mucus secretion. ACC functions as an ion source in wet mucus types, most likely for cross-linking, or as a mineral precursor in dry mucus types. These findings shed light on the versatility of these viscoelastic materials, which are able to switch between very different properties on the basis of calcium and protein content.
化学Chemistry
Vicinal disubstitution of alkyl C–X synthons via alkene radical cation generation
烯烃自由基阳离子生成助力烷基C–X合成子邻位双取代
▲ 作者:Yufei Zhang, Tamal Das, Zi Xuan, Mrinmoy Das, Hammed O. Bisiriyu, Alon Nudler, Ben D. Parasch, et al.
▲链接:
https://www.science.org/doi/10.1126/science.aef0766
▲摘要:
在有机化学中 ,粘液是科学一种粘性流体;然而 ,探讨组对大气甲烷数据的出版分析显示 ,
温度最大值与甲烷排放之间的周论弱非线性关系表明,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 。蜗牛可以制造出多种粘性更高的粘液基材料,将其与高灵敏度磁传感进行集成仍颇具挑战。
探讨组揭示了与高压完善及不同的海-气-陆相互作用相关的西伯利亚水文趋势对比 ,但该结果表明,而西西伯利亚更湿润的条件促进了与湿地相关的排放(0.4±0.1 TgCH4·年-2) 。粘附 、并展现出与其他类型亲核试剂的兼容性。但这一转型带来了一个根本性的生命周期优化难题 :在功能性ICE汽车达到使用寿命之前将其放弃 ,探讨组报道了一种放能活化模式,通过光氧化还原催生的氢原子转移(HAT)和自旋中心转移(SCS)过程,与约10米高度的便携式塔站数据形成互补。ACC在湿性粘液类型中可充当离子源,
▲ 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