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Science, 23 AUG 2024, VOL 385, ISSUE 6711

《明升体育app》，2024年8月23日，第385卷，6711期

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材料明升体育appMaterials Science

Recyclable surgical, consumer, and industrial adhesives of poly(α-lipoic acid)

聚α-硫辛酸助力可回收外科、消费和工业粘合剂

▲ 作者：SUBHAJIT PAL, JISOO SHIN, KELSEY DEFRATES, MUSTAFA ARSLAN, KATELYN DALE, HANNAH CHEN, ET AL.

▲ 链接：

▲ 摘要：

聚合物粘合剂在许多医疗、消费和工业产品中发挥着重要作用。α-硫辛酸（αLA）聚合物具有满足多用途和环境友好型粘合剂需求的潜力，但其性能受限于自发解聚。

研究组报道了一系列稳定的αLA聚合物粘合剂，可针对各种医疗或非医疗用途量身定制，并以闭环方式可持续获取和回收。

单体组成的微小变化提供了在干燥和潮湿条件下功能良好的压敏粘合剂，以及与传统环氧树脂强度相当的结构粘合剂。αLA外科强力胶成功封闭小鼠羊膜囊破裂，使鼠胎存活率从0提高到100%。

▲ Abstract：

Polymer adhesives play an important role in many medical, consumer, and industrial products. Polymers of α-lipoic acid (αLA) have the potential to fulfill the need for versatile and environmentally friendly adhesives, but their performance is plagued by spontaneous depolymerization. We report a family of stabilized αLA polymer adhesives that can be tailored for a variety of medical or nonmedical uses and sustainably sourced and recycled in a closed-loop manner. Minor changes in monomer composition afforded a pressure-sensitive adhesive that functions well in dry and wet conditions, as well as a structural adhesive with strength equivalent to that of conventional epoxies. αLA surgical superglue successfully sealed murine amniotic sac ruptures, increasing fetal survival from 0 to 100%.

Manufacture and testing of biomass-derivable thermosets for wind blade recycling

生物质衍生热固性材料的制造和测试助力风力叶片回收

▲ 作者：RYAN W. CLARKE, ERIK G. ROGNERUD, ALLEN PUENTE-URBINA, DAVID BARNES, PAUL MURDY, MICHAEL L. MCGRAW, ET AL.

▲ 链接：

▲摘要：

风能有助于电网脱碳，但风力叶片不可回收，目前的报废管理策略不可持续。

为了解决可持续能源基础设施中材料可回收性的挑战，研究组引入了可扩展的生物质衍生聚酯共价适应性网络和相应的纤维增强复合材料，用于可回收风力叶片制造。通过实验和计算研究（包括9米风力叶片原型的真空辅助树脂转移模塑），研究组证明了这种材料与现有制造技术的良好兼容性，相对于现有材料的优越性能，以及实用的报废明升手机品可回收性。

最值得注意的是尽管采用了动态交联拓扑结构，但反直觉的蠕变抑制仍优于行业最先进的热固性材料。总体而言，该研究详细介绍了风力叶片制造的诸多方面，包括明升手机、工程、安全、机械分析、风化和明升手机可回收性，使生物质衍生、可回收的风力叶片成为现实。

▲ Abstract：

Wind energy is helping to decarbonize the electrical grid, but wind blades are not recyclable, and current end-of-life management strategies are not sustainable. To address the material recyclability challenges in sustainable energy infrastructure, we introduce scalable biomass-derivable polyester covalent adaptable networks and corresponding fiber-reinforced composites for recyclable wind blade fabrication. Through experimental and computational studies, including vacuum-assisted resin-transfer molding of a 9-meter wind blade prototype, we demonstrate drop-in technological readiness of this material with existing manufacture techniques, superior properties relative to incumbent materials, and practical end-of-life chemical recyclability. Most notable is the counterintuitive creep suppression, outperforming industry state-of-the-art thermosets despite the dynamic cross-link topology. Overall, this report details the many facets of wind blade manufacture, encompassing chemistry, engineering, safety, mechanical analyses, weathering, and chemical recyclability, enabling a realistic path toward biomass-derivable, recyclable wind blades.

明升手机Chemistry

Reductive samarium (electro)catalysis enabled by SmIII-alkoxide protonolysisSmIII

醇盐质子分解实现还原钐（电）催化

▲ 作者：EMILY A. BOYD, CHUNGKEUN SHIN, DAVID J. CHARBONEAU, JONAS C. PETERS AND SARAH E. REISMAN.

▲ 链接：

▲ 摘要：

二碘化钐（SmI2）是一种特殊的单电子还原剂，可用于各种合成环境。然而，由于与裂解强SmIII-O键相关的众所周知的挑战，催化周转的通用方法仍难以实现。先前的工作集中在使用高反应性亲氧试剂来实现催化剂周转。但这种方法导致催化剂形态复杂，从本质上限制了合成范围。

研究组利用温和且具有选择性的质子分解策略，实现了钐催化的广泛范围内酮和丙烯酸酯的分子间还原交叉偶联。该方法的模块化实现了基于溶剂、pKa（其中Ka是酸解离常数）和钐配位范围来合理控制选择性，并为催化和电催化镧系明升手机的未来发展提供了基础。

▲ Abstract：

Samarium diiodide (SmI2) is a privileged, single-electron reductant deployed in diverse synthetic settings. However, generalizable methods for catalytic turnover remain elusive because of the well-known challenge associated with cleaving strong SmIII-O bonds. Prior efforts have focused on the use of highly reactive oxophiles to enable catalyst turnover. However, such approaches give rise to complex catalyst speciation and intrinsically limit the synthetic scope. Herein, we leveraged a mild and selective protonolysis strategy to achieve samarium-catalyzed, intermolecular reductive cross-coupling of ketones and acrylates with broad scope. The modularity of our approach allows rational control of selectivity based on solvent, pKa (where Ka is the acid dissociation constant), and the samarium coordination sphere and provides a basis for future developments in catalytic and electrocatalytic lanthanide chemistry.

地球明升体育appEarth Science

Slow rupture in a fluid-rich fault zone initiated the 2024 Mw 7.5 Noto earthquake

富流体断层带的缓慢破裂引发了2024年能登半岛7.5级地震

▲ 作者：ZHANGFENG MA, HONGYU ZENG, HAIPENG LUO, ZEMIN LIU, YU JIANG, YOSUKE AOKI, ET AL.

▲ 链接：

▲摘要：

2024年发生在日本能登半岛的7.5级地震由复杂的断裂过程引发，对社区造成了破坏。

利用空间大地测量和地震观测，研究组表明该事件使半岛变形，西海岸的峰值隆升达到5米。近海断层的浅层滑动超过10米。峰值应力降大于10兆帕。

这一毁灭性事件始于震源附近持续15至20秒的缓慢破裂传播，自2020年以来，由于地壳下的流体供应，地震群激增。缓慢的启动伴随着强烈的高频地震辐射。这些观测结果表明，在富流体断层带内存在明显的同震滑动模式，反映了断层性质的高度异质性。

▲ Abstract：

The 2024 moment magnitude 7.5 Noto Peninsula (Japan) earthquake caused devastation to communities and was generated by a complex rupture process. Using space geodetic and seismic observations, we have shown that the event deformed the peninsula with a peak uplift reaching 5 meters at the west coast. Shallow slip exceeded 10 meters on an offshore fault. Peak stress drop was greater than 10 megapascals. This devastating event began with a slow rupture propagation lasting 15 to 20 seconds near its hypocenter, where seismic swarms had surged since 2020 because of lower-crust fluid supply. The slow start was accompanied by intense high-frequency seismic radiation. These observations suggest a distinct coseismic slip mode reflecting high heterogeneity in fault properties within a fluid-rich fault zone.

Dual-initiation ruptures in the 2024 Noto earthquake encircling a fault asperity at a swarm edge

2024年能登地震中环震群边缘断层粗糙度的双重引发破裂

▲ 作者：LIUWEI XU, CHEN JI, LINGSEN MENG, JEAN-PAUL AMPUERO, ZHANG YUNJUN, SAEED MOHANNA, ET AL.

▲ 链接：

▲摘要：

为了揭示2024年日本能登7.5级地震与之前地震活动群之间的联系，研究组通过近源波形分析和震源成像技术，结合地震和大地测量数据集，研究了其破裂过程。

结果在初始破裂阶段发现了明显的复杂性。在之前的地震群中保持完整的强烈断层粗糙度减缓了破裂速度。然后，二次破裂始于粗糙度的另一边，粗糙度无法抵挡双钳形破裂前缘。这种高应力降粗糙度的失败使地震演变为大规模事件。

该观测结果有助于揭示断层粗糙度在控制震群迁移和破裂传播方面的关键作用，并强调需要进行详细的地震学和跨学科研究来评估震群易发地区的地震风险。

▲ Abstract：

To reveal the connections between the 2024 moment magnitude (Mw) 7.5 Noto earthquake in Japan and the seismicity swarms that preceded it, we investigated its rupture process through near-source waveform analysis and source imaging techniques, combining seismic and geodetic datasets. We found notable complexity in the initial rupture stages. A strong fault asperity, which remained unbroken in preceding seismic swarms, slowed down the rupture. Then, a second rupture initiated at the opposite edge of the asperity, and the asperity succumbed to double-pincer rupture fronts. The failure of this high-stress drop asperity drove the earthquake into a large-scale event. Our observations help unravel the crucial role of fault asperities in controlling swarm migration and rupture propagation and underscore the need for detailed seismological and interdisciplinary studies to assess seismic risk in swarm-prone regions.

Climate policies that achieved major emission reductions: Global evidence from two decades

实现大幅减排的气候政策：二十年的全球证据

▲ 作者：ANNIKA STECHEMESSER, NICOLAS KOCH, EBBA MARK, ELINA DILGER, PATRICK KL?SEL, LAURA MENICACCI, ET AL.

▲ 链接：http://www.science.org/doi/10.1126/science.adl6547

▲摘要：

要实现《巴黎协定》的气候目标，就必须更好地了解哪些气候政策能在必要规模上减少排放。

研究组提供了一项全球系统的事后评估，以确定在1998年至2022年间在六大洲41个国家实施的1500项气候政策中导致大幅减排的政策组合。该方法将一个全面的气候政策数据库与基于机器学习的通用双重差分法的扩展相结合。共确定了63项成功的政策干预措施，总减排量在6亿至18亿吨二氧化碳之间。

研究组对有效但罕有研究的政策组合的见解强调了基于价格的工具在精心设计的政策组合中的重要作用，以及缩小排放差距所需的政策努力。

▲ Abstract：

Meeting the Paris Agreement’s climate targets necessitates better knowledge about which climate policies work in reducing emissions at the necessary scale. We provide a global, systematic ex post evaluation to identify policy combinations that have led to large emission reductions out of 1500 climate policies implemented between 1998 and 2022 across 41 countries from six continents. Our approach integrates a comprehensive climate policy database with a machine learning–based extension of the common difference-in-differences approach. We identified 63 successful policy interventions with total emission reductions between 0.6 billion and 1.8 billion metric tonnes CO₂. Our insights on effective but rarely studied policy combinations highlight the important role of price-based instruments in well-designed policy mixes and the policy efforts necessary for closing the emissions gap.