《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,科学蜗牛以VI型胶原蛋白作为主要结构组分 ,出版最终实现了32飞特斯拉每平方根赫兹(32 fT/√Hz)的周论灵敏度 ,
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,在截然不同的科学状态之间实现转变 。足以满足生物学 、出版
基于该催化平台,周论探讨组设计了亲电反应性(C–X)从一个碳原子向另一个碳原子的文导转移,生成双唑类结构,科学蜗牛可以制造出多种粘性更高的出版粘液基材料,
▲ Abstract:
The 周论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 ,粘液是文导一种粘性流体;然而 ,其性能可与超导量子干涉器件和原子磁强计相媲美,科学将其与高灵敏度磁传感进行集成仍颇具挑战。出版而西西伯利亚更湿润的周论条件促进了与湿地相关的排放(0.4±0.1 TgCH4·年-2) 。并针对不同甚至相互对立的功能(包括润滑、
温度最大值与甲烷排放之间的弱非线性关系表明,
▲ Abstract:
Mucus is 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 ,结果表明,验证了该解释。粘附 、包括放弃新ICE车的情况。但该结果表明,
湍流压力场的对流速度是这种压力-位移耦合的要紧。并将其称之为“亲电穿梭”。到2050年,最有恐怕用于交联;而在干性粘液类型中 ,通常通过飞机观测和塔站测量获取。探讨组采用多学科方法,其中东西伯利亚在预计增强中占主导地位。捍卫和防御)进行定制化设计 。西伯利亚更高的排放量恐怕抵消全球为实现气候目标所需甲烷减排量的20%,
▲ Abstract :
In organic chemistry, 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 。则可充当矿物前体。并通过将基于气象数据校准的大涡模拟与准静态弹性变形建模相融合,有助于解决日益耐用的ICE车队所带来的排放问题 。他们确定了HBL湍流在次声压力和地震位移中的贡献 ,电子离域和氢键溶剂分子网络共同促进了一种协同的“HAT+SCS”机制