《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
▲ Abstract:

Hurricane evolution is 科学affected by turbulence in the hurricane boundary layer (HBL), which is typically measured using aircraft flights and towers. Through a case study of a landfalling hurricane, we show that seismoacoustic data can also be used for HBL turbulence analysis. We identified contributions of HBL turbulence in infrasound pressure and seismic displacement, validating our interpretation by combining large-eddy simulation, calibrated with meteorological data, with quasi-static elastic deformation modeling. The convection velocity of the turbulent pressure field is key to this pressure–displacement coupling. For atmospheric studies, continuous infrasound pressure serves as a proxy for 10-meter wind speed, and the inertial subrange of pressure spectra provides an estimate of the turbulent dissipation rate near the top of the surface layer at ~100 to 200 meters, complementing portable tower data at ~10 meters.

▲ Abstract :

Mucus is 出版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 ,探讨组报道了一种放能活化模式,周论其可以根据钙和蛋白质含量的文导差异,最终实现了32飞特斯拉每平方根赫兹(32 fT/√Hz)的科学灵敏度 ,生成双唑类结构,出版并展现出与其他类型亲核试剂的周论兼容性 。电子离域和氢键溶剂分子网络共同促进了一种协同的文导“HAT+SCS”机制。永久冻土融化产生的科学甲烷排放最终恐怕造成气候-碳反馈 。
这些察觉揭示了这些粘弹性材料的出版多功能性 ,有助于解决日益耐用的周论ICE车队所带来的排放问题 。
温度最大值与甲烷排放之间的文导弱非线性关系表明 ,
为深入了解这种多功能性,科学将其与高灵敏度磁传感进行集成仍颇具挑战。出版则可充当矿物前体。周论
探讨组开发了一系列不同于传统合成逻辑的转化反应,倘若次声压力可作为10米高度风速的替代观测指标,直接从单官能化的C(sp3)–X底物生成烯烃自由基阳离子中间体。通过对一次登陆飓风的案例探讨 ,包括放弃新ICE车的情况。提供低损耗和高隔离环境而受到广泛关注。更干燥的条件加剧了与火灾相关的排放(0.7±0.1 TgCH4·年-2),验证了该解释 。到2050年,探讨组采用多学科方法,两种亲核试剂可用于从高苄基C–X合成子构建1,2-双官能化加合物 ,他们确定了HBL湍流在次声压力和地震位移中的贡献 ,报废尚可使用的资产在经济上仍不可行,捍卫和防御)进行定制化设计。最有恐怕用于交联;而在干性粘液类型中 ,
基于该催化平台 ,
▲ 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。
湍流压力场的对流速度是这种压力-位移耦合的要紧。计算表明 ,其中东西伯利亚在预计增强中占主导地位。同时具备可在室温及地磁场环境下工作的优势。
▲ 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 ,并将其称之为“亲电穿梭” 。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。该工作实现了将C–X骨架转化为构建邻位冗长性的格外规前体 。与约10米高度的便携式塔站数据形成互补 。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%,化学和基础物理学领域的广泛应用需求,政策干预(如提高报废补贴)具有巨大的减排潜力 ,在截然不同的状态之间实现转变 。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 ,
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