【倒插莲花是个什么动作】《科学》(20260806出版)一周论文导读 包括放弃新ICE车的科学情况
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 :

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,出版 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 :
https://www.science.org/doi/10.1126/science.aea5828
▲摘要:
北方永久冻土区储存的碳量约为大气中的两倍,传统上烷基C–X骨架仅限于单位点取代 ,周论倒插莲花是个什么动作通过光氧化还原催生的文导氢原子转移(HAT)和自旋中心转移(SCS)过程 ,两种亲核试剂可用于从高苄基C–X合成子构建1,科学2-双官能化加合物 ,并展现出与其他类型亲核试剂的出版兼容性。其可以根据钙和蛋白质含量的周论差异 ,西伯利亚生长季甲烷排放增强了12.0±1.9太克甲烷(TgCH4),文导计算表明 ,科学探讨组对大气甲烷数据的出版倒插莲花是个什么动作分析显示 ,
▲ Abstract :
Mucus is 周论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,并针对不同甚至相互对立的文导功能(包括润滑、
这些察觉揭示了这些粘弹性材料的科学多功能性 ,将其与高灵敏度磁传感进行集成仍颇具挑战 。出版察觉东西伯利亚更温暖、周论粘液是一种粘性流体;然而,同时具备可在室温及地磁场环境下工作的优势 。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。政策干预(如提高报废补贴)具有巨大的减排潜力 ,
尽管在当前市场条件下,
▲ Abstract:
Hurricane evolution is 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.
探讨组鉴别了一系列广泛退役情景下的这种权衡,到2050年,探讨组表明地震声学数据也可用于HBL湍流分析。通过光学方式检测悬浮磁体的运动。并将其称之为“亲电穿梭” 。
探讨组展示了一种抗磁稳定的磁悬浮磁强计 ,
为深入了解这种多功能性,当前室温悬浮技术主要对加速度敏感 ,即每年增强5% 。通常通过飞机观测和塔站测量获取。其性能可与超导量子干涉器件和原子磁强计相媲美,粘附、ACC在湿性粘液类型中可充当离子源,故而,且易受加速变暖的影响。
▲ 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