《科学》（20260423出版）一周论文导读

 

编译|未玖

材料科学Materials Science

Intercalated carbon nanotube fibers with high specific electrical conductivity

具有高比电导率的嵌入碳纳米管纤维

▲ 作者：A. I. DE ISIDRO-GóMEZ , V. VASSILEV-GALINDO, A. MIKHALCHAN, M. PELAEZ-FERNANDEZ, J. LLORCA, R. ARENAL, ET AL.

▲链接：

https://www.science.org/doi/10.1126/science.aeb0673

▲摘要：

将单根碳纳米管导电性转化为可实际应用的宏观导体，至今仍是一项难题。

研究组报道了一种高度排列的双壁碳纳米管纤维，其管间通道内嵌入了四氯铝酸根阴离子（AlCl4^-）链。四氯铝酸根嵌入物可作为非共价掺杂剂，每个阴离子可捕获0.65个电子，电子主要来源于外纳米管层。

结合17%的嵌入物体积占比，该材料室温导电率大幅提升至最高24.5兆西门子/米，达到纯铜导电率的41%。其比电导率值高达17345西门子·平方米每千克，优于各类金属材料。

该碳纳米管纤维的强度是传统架空电缆的5倍，重量仅为其一半；在干燥环境下性能稳定，且得益于电缆聚合物护套的防潮保护，仍能保留80%的导电性。

▲ Abstract：

Translating the conductivity of individual carbon nanotubes into practical, macroscopic conductors remains a challenge. We report highly aligned fibers of double-walled carbon nanotubes intercalated with chains of tetrachloroaluminate anions (AlCl4^-

) in the intertube channels. The AlCI4^- intercalant acts as a noncovalent dopant, accepting 0.65 electrons per anion, mostly from the outer nanotube layer. Combined with a 17% intercalant volume fraction, it produces an increase in room-temperature conductivity to values as high as 24.5 mega-Siemens per meter, which is 41% of that of copper. Specific conductivity values reach 17,345 Siemens-meter squared per kilogram, which is superior to that of metals. These fibers are five times stronger and half the weight of conventional overhead cables while remaining stable in dry conditions and retaining 80% of their conductivity protected from moisture by a cable polymer sheath.

Programming touch-me-not knot topologies for rapid and diverse leaping and flying motions

编程“含羞草”结拓扑以实现快速多样的跳跃与飞行运动

▲ 作者：JYAOYE HONG, WEIXUAN LIU, YINDING CHI, ANTONIO PROCTOR MARTINEZ, BINGZHI HE, ZIYUN ZHANG, KUN-YU WANG, ET AL.

▲ 链接：https://www.science.org/doi/10.1126/science.aed0434

▲摘要：

人们希望微型跳跃机器人能够执行快速、可编程且多模式的运动。

研究组提出了利用由凯夫拉增强液晶弹性体（LCE）复合纤维制成的毫米级结在受热时触发冲击式解结过程的新策略。

具有扭曲介晶的（LCE）壳体在外界刺激下发生扭转变形，产生能够克服摩擦力的驱动力，将储存的弹性势能转化为动能，并根据结的拓扑结构以不同的起跳后运动实现高而快的跳跃。

通过调控弯扭耦合以及解结次数，研究组实现了翻转、旋转以及连续空中体操动作。

研究组还对起飞后的飞行进行编程，包括通过集成机翼实现了自返航和垂直下降。编码拓扑结构与各向异性为编程软体机器人实现快速、敏捷、高效的运动提供了丰富的设计空间。

▲ Abstract：

Miniature leaping robots are desired to perform fast, programmable, and versatile motions. In this study, we present our approach for harnessing the impulsive unknotting process triggered upon heating millimeter-sized knots made from Kevlar-reinforced liquid crystal elastomer (LCE) composite fibers. The LCE shell with twisted mesogens undergoes torsional deformation, generating an actuation force that overcomes friction, converting the stored elastic energy into kinetic energy for launching tall and rapid leaps with diverse posttakeoff motions depending on the knot topology. By manipulating the bending-twisting coupling and the unknotting numbers, we realize flipping, spinning, and sequential gymnastic in-air motions. We further program posttakeoff flight, including self-return and vertical descent by integrating a wing. Encoding topology and anisotropy provides a rich design space to program soft robots for rapid, agile, and highly efficient motions.

化学Chemistry

Molecular solar thermal energy storage in Dewar pyrimidone beyond 1.6 megajoules per kilogramt

杜瓦嘧啶酮中的分子太阳能热储能超过1.6兆焦耳/千克

▲ 作者：HAN P. Q. NGUYEN, ALEXANDER J. MAERTENS, BENJAMIN A. BAKER, NATHAN M.-W. WU, ZIHAO YE, QINGYANG ZHOU, ET AL.

▲链接：

https://www.science.org/doi/10.1126/science.aec6413

▲摘要：

将阳光以紧凑且可再充电的形式存储仍是太阳能利用的核心挑战。分子太阳能热（MOST）储能系统能够捕获光子能量并按需以热能形式释放，这提供了一种直接方法，但长期未能达到实际应用标准。

受DNA结构启发，研究组报道了一种基于嘧啶酮的MOST系统，该系统在300纳米光激发下将能量储存于张力态杜瓦光异构体中。

该设计以可持续性为理念，可在无溶剂条件下运行，并能与水性环境兼容，同时克服了该领域最大障碍之一——存储热量的可控提取与转移。

在酸催化下，杜瓦异构体释放的热量足以使约0.5毫升水沸腾。这些进展有助于为分布式太阳能储热及离网能源解决方案指明方向。

▲ Abstract：

Storing sunlight in a compact and rechargeable form remains a central challenge for solar energy utilization. Molecular solar thermal (MOST) energy storage systems, which harness photon energy and release it as heat on demand, provide a direct approach but have long failed to meet practical benchmarks. Inspired by the architecture of DNA, we report a pyrimidone-based MOST system that stores energy in the strained Dewar photoisomer upon excitation at 300 nanometers. Designed with sustainability in mind, the system operates solvent free and remains compatible with aqueous environments while overcoming one of the field’s greatest hurdles—the controlled extraction and transfer of stored heat. When catalyzed by acid, the Dewar isomer releases enough heat to boil water (~0.5 milliliters). These advances help point the way toward decentralized solar heat storage and off-grid energy solutions.

Chiral S(VI) platform unifies selective C–H amination of complex molecules and alkane feedstocks

手性硫（VI）平台整合了复杂分子和烷烃原料的选择性C-H胺化

▲ 作者：TUAN ANH TRINH, DEREK B. HU, ANNA J. KENNY, ETHAN M. WARRINGTON, STANISLAV CHEREMPEI, ILIA A. GUZEI, ET AL.

▲链接：

https://www.science.org/doi/10.1126/science.aee3321

▲摘要：

复杂分子与简单烷烃对催化剂控制的碳-氢（C-H）键官能团化提出了截然不同的挑战。密集官能团化的骨架需要在多个反应位点中实现精准靶向，同时耐受敏感官能团；而缺乏导向基团的未活化底物则需选择性激活那些极其惰性、几乎相同的C-H键。

研究组通过将一个经典手性辅助基重新利用，构建了一个由银催化与手性硫（VI）氮宾前体介导的统一、选择性强且可预测的C-H胺化平台。该系统不仅能够对活化C-H键进行立体发散性的后期胺化，具有广泛的官能团耐受性和水性环境兼容性，还能介导化学原料的温和、选择性胺化。

硫（VI）基序功能作为一个模块化、立体构型明确且具有药物相关性的合成枢纽，可快速实现化合物库的多样化，既支持靶向合成，也支持多样性导向合成。

▲ Abstract：

Complex molecules and simple alkanes pose distinct challenges for catalyst-controlled carbon-hydrogen (C–H) functionalizations. Whereas densely functionalized scaffolds require precise targeting among multiple reactive sites while tolerating sensitive functionalities, unactivated substrates that lack directing groups require selective activation of exceptionally inert, nearly identical C–H bonds. In this work, we addressed both challenges by repurposing a classic chiral auxiliary into a unified, selective, and predictable C–H amination platform mediated by silver catalysis and chiral sulfur(VI) nitrene precursors. This system enables stereodivergent, late-stage aminations of activated C–H bonds with broad functional group tolerance and compatibility with aqueous conditions while also mediating mild, selective aminations of chemical feedstocks. The sulfur(VI) motif functions as a modular, stereodefined, and medicinally relevant synthetic linchpin for rapid library diversification, enabling both target- and diversity-oriented synthesis.

地球科学Earth Science

An unrecognized mode of small particles in the lower stratosphere

平流层下方一种未被识别的小颗粒模式

▲ 作者：MING LYU, ADAM T. AHERN, GREGORY P. SCHILL, MICHAEL J. LAWLER, DANIEL M. MURPHY, SAMUEL J. TAYLOR,

▲链接：

https://www.science.org/doi/10.1126/science.adw8939

▲摘要：

对近期现场数据的分析揭示，在19公里以下的平流层，一氧化二氮（N2O）体积比大于270ppb的区域，存在一种持续性的富含有机物气溶胶粒子模式，其数量几何平均直径约为0.03～0.11微米（表面积几何平均直径为0.08～0.2微米，体积几何平均直径为0.11～0.3微米）。

该模式主要由从对流层输送而来的富含有机物的颗粒组成，难以被卫星及大多数球载光学测量手段有效探测，却在非均相反应的表面积和可冷凝蒸汽的汇中占据主导地位。这些小颗粒在与先前的平流层空气混合时，尺寸增大而浓度降低。

现有的全球化学-气候模型未能重现这些颗粒的特征，这表明模型改进对于准确评估拟议中的地球工程方案是必要的。

▲ Abstract：

Analysis of recent in situ data reveals a persistent mode of organic-rich aerosol particles in the stratosphere below 19 kilometers at nitrous oxide (N2O) > 270 parts per billion by volume, with a number geometric mean diameter of ~0.03 to 0.11 μm (0.08 to 0.2 μm in surface and 0.11 to 0.3 μm in volume). This mode, composed mostly of organic-rich particles transported from the troposphere, is poorly sensed by satellites and most balloon-borne optical measurements but dominates the surface area for heterogeneous reactions and the sink for condensable vapors. These small particles grow in size and decrease in concentration as they mix with older stratospheric air. A global chemistry-climate model fails to replicate the characteristics of these particles, suggesting that model improvements are necessary for accurate assessment of proposed geoengineering efforts.

Amazon forest loss: An all-sky biophysical top-of-atmosphere cooling feedback

亚马逊森林损失：全天空生物物理大气顶部冷却反馈

▲ 作者：TOM DROR AND GRAHAM FEINGOLD

▲链接：

https://www.science.org/doi/10.1126/science.adz8296

▲摘要：

亚马逊雨林在调节地球能量与水循环中发挥着关键作用。然而，森林砍伐的全部生物物理影响仍未明确，特别是通过云所介导的部分。

利用二十年的多源卫星观测数据，研究组分离出森林损失的生物物理信号，并展示了整合地表与大气效应的全天空生物物理反馈观测结果。

结果发现，短波和长波辐射通量中的大气层顶（TOA）冷却效应与森林损失率呈线性关系，其中短波占主导。

在高森林损失区域，短波TOA冷却达到6.8±0.6瓦/平方米，而云驱动的反照率增加使其相比于仅地表增亮的情况提升了一倍。这些发现强调了云响应在估算森林覆盖变化对气候影响中的重要性，并支持将其纳入气候模型与土地管理政策中。

▲ Abstract：

The Amazon rainforest plays a crucial role in regulating Earth’s energy and water cycles. The full biophysical impact of deforestation, particularly when mediated by clouds, remains elusive. Using two decades of multisource satellite observations, we isolate biophysical signals of forest loss and present an observation of the all-sky biophysical feedback that integrates surface and atmospheric effects. We find that top-of-atmosphere (TOA) cooling in shortwave and longwave fluxes scales with forest loss fraction, with shortwave dominating. In high-loss areas, shortwave TOA cooling reaches 6.8 ± 0.6 watts per square meter, with cloud-driven albedo increases doubling the effect relative to surface brightening alone. These findings underscore the importance of cloud responses in estimating the climatic impact of forest cover change and support their integration into climate models and land-management policies.