《科學》（20240419出版）一周論文導讀

編譯 | 未玖

Science, 19 APR 2024, VOL 384, ISSUE 6693

《科學》2024年4月19日，第384卷，6693期

天文學Astronomy

Dating the Solar System’s giant planet orbital instability using enstatite meteorites

用頑輝石隕石測定太陽系巨行星軌道不穩定時期

▲ 作者：CHRYSA AVDELLIDOU, MARCO DELBO’, DAVID NESVORNÝ, KEVIN J. WALSH & ALESSANDRO MORBIDELLI

▲ 連結：

https://www.science.org/doi/10.1126/science.adg8092

▲ 摘要：

太陽系的巨行星最初在緊湊軌道上形成，由于軌道不穩定過渡至目前更寬的結構。這種不穩定發生的時機很難确定。

研究組使用動力學模拟來證明軌道不穩定将類地行星區域的星子碎片植入小行星主帶。使用隕石資料表明，植入發生在太陽系誕生後超6000萬年。

将這一限制條件與先前從木星特洛伊小行星中得出的上限相結合，研究組得出結論，軌道不穩定發生在太陽系誕生後6000萬年至1億年。形成月球的巨大撞擊發生在該時期，是以其可能與巨行星不穩定有關。

▲ Abstract：

The giant planets of the Solar System formed on initially compact orbits, which transitioned to the current wider configuration by means of an orbital instability. The timing of that instability is poorly constrained. In this work, we use dynamical simulations to demonstrate that the instability implanted planetesimal fragments from the terrestrial planet region into the asteroid main belt. We use meteorite data to show that the implantation occurred >60 million years (Myr) after the Solar System began to form. Combining this constraint with a previous upper limit derived from Jupiter’s trojan asteroids, we conclude that the orbital instability occurred 60 to 100 Myr after the beginning of Solar System formation. The giant impact that formed the Moon occurred within this range, so it might be related to the giant planet instability.

材料科學Materials Science

Structural disorder determines capacitance in nanoporous carbons

結構無序決定了納米多孔碳的電容

▲ 作者：XINYU LIU, DONGXUN LYU, CÉLINE MERLET, MATTHEW J. A. LEESMITH, XIAO HUA, ZHEN XU, ET AL.

▲ 連結：

https://www.science.org/doi/10.1126/science.adn6242

▲ 摘要：

納米多孔碳電極複雜結構的表征困難導緻缺乏明确的設計原則來改進超級電容器。孔徑尺寸一直被認為是提高電容的主要杠杆。

然而，研究組對大量商業納米多孔碳的評估發現孔徑和電容之間缺乏相關性。相反，核磁共振波譜測量和模拟揭示了電極結構無序和電容之間的強烈相關性。

具有更小的類石墨烯結構域的無序碳因在其納米孔中更有效地存儲離子，進而表現出更高的電容。該發現提出了了解和利用無序來實作高能量密度超級電容器的方法。

▲ Abstract：

The difficulty in characterizing the complex structures of nanoporous carbon electrodes has led to a lack of clear design principles with which to improve supercapacitors. Pore size has long been considered the main lever to improve capacitance. However, our evaluation of a large series of commercial nanoporous carbons finds a lack of correlation between pore size and capacitance. Instead, nuclear magnetic resonance spectroscopy measurements and simulations reveal a strong correlation between structural disorder in the electrodes and capacitance. More disordered carbons with smaller graphene-like domains show higher capacitances owing to the more efficient storage of ions in their nanopores. Our findings suggest ways to understand and exploit disorder to achieve highly energy-dense supercapacitors.

High energy density in artificial heterostructures through relaxation time modulation

通過弛豫時間調制實作人工異質結構的高能量密度

▲ 作者：SANGMOON HAN, JUSTIN S. KIM, EUGENE PARK, YUAN MENG, ZHIHAO XU, ALEXANDRE C. FOUCHER, ET AL.

▲ 連結：

https://www.science.org/doi/10.1126/science.adl2835

▲ 摘要：

靜電電容器因其超快的充放電能力成為先進電子器件和大功率電氣系統的基礎元件。鐵電材料具有較高的最大極化，但高殘餘極化阻礙了其在儲能應用中的有效部署。先前方法由于鐵電材料結晶度退化而遭遇瓶頸。

研究組介紹了一種利用二維（2D）材料控制弛豫時間的方法，同時通過使用2D/3D/2D異質結構來最小化能量損失，并保持鐵電3D材料的結晶度。使用該方法可實作191.7 J/cm3的能量密度，效率超過90%。

這種對弛豫時間的精确控制有望促進廣泛應用，并有潛力加速高效儲能系統的發展。

▲ Abstract：

Electrostatic capacitors are foundational components of advanced electronics and high-power electrical systems owing to their ultrafast charging-discharging capability. Ferroelectric materials offer high maximum polarization, but high remnant polarization has hindered their effective deployment in energy storage applications. Previous methodologies have encountered problems because of the deteriorated crystallinity of the ferroelectric materials. We introduce an approach to control the relaxation time using two-dimensional (2D) materials while minimizing energy loss by using 2D/3D/2D heterostructures and preserving the crystallinity of ferroelectric 3D materials. Using this approach, we were able to achieve an energy density of 191.7 joules per cubic centimeter with an efficiency greater than 90%. This precise control over relaxation time holds promise for a wide array of applications and has the potential to accelerate the development of highly efficient energy storage systems.

More resilient polyester membranes for high-performance reverse osmosis desalination

恢複力更強的聚酯膜助力高性能反滲透海水淡化

▲ 作者：YUJIAN YAO, PINGXIA ZHANG, FEI SUN, WEN ZHANG, MENG LI, GANG SHA, ET AL.

▲ 連結：

https://www.science.org/doi/10.1126/science.adk0632

▲ 摘要：

近半個世紀以來，薄膜複合反滲透膜一直是海水淡化和水淨化的黃金标準技術。聚酰胺膜具有優異的透水性和拒鹽性，但也有耐氯性差、結垢傾向高和拒硼率低的缺點。

研究組通過分子設計聚酯膜複合反滲透膜來解決這些問題，使用共溶劑輔助界面聚合法使3,5-二羟基-4-甲基苯甲酸與均苯三甲酰氯反應。這種聚酯膜具有優異的透水性，對氯化鈉和硼高截留，以及完全耐氯。

與聚酰胺膜相比，該膜的超光滑、低能量表面還可防止污垢和礦物結垢。通過進一步優化水鹽選擇性，該膜有望超越聚酰胺膜，為大大減少海水淡化的預處理步驟提供新途徑。

▲ Abstract：

Thin-film composite reverse osmosis membranes have remained the gold standard technology for desalination and water purification for nearly half a century. Polyamide films offer excellent water permeability and salt rejection but also suffer from poor chlorine resistance, high fouling propensity, and low boron rejection. We addressed these issues by molecularly designing a polyester thin-film composite reverse osmosis membrane using co-solvent–assisted interfacial polymerization to react 3,5-dihydroxy-4-methylbenzoic acid with trimesoyl chloride. This polyester membrane exhibits substantial water permeability, high rejection for sodium chloride and boron, and complete resistance toward chlorine. The ultrasmooth, low-energy surface of the membrane also prevents fouling and mineral scaling compared with polyamide membranes. These membranes could increasingly challenge polyamide membranes by further optimizing water-salt selectivity, offering a path to considerably reducing pretreatment steps in desalination.

人工智能Artificial Intelligence

Fusion of memristor and digital compute-in-memory processing for energy-efficient edge computing

融合憶阻器和數字記憶體計算處理助力高效邊緣計算

▲ 作者：TAI-HAO WEN, JE-MIN HUNG, WEI-HSING HUANG, CHUAN-JIA JHANG, YUN-CHEN LO, HUNG-HSI HSU, ET AL.

▲ 連結：

https://www.science.org/doi/10.1126/science.adf5538

▲ 摘要：

人工智能（AI）邊緣裝置更傾向于采用高容量非易失性記憶體計算（CIM）來實作高能效和足夠準确的快速喚醒響應。大多數先前的工作要麼依據基于憶阻器的CIM，但因其耐用性有限而遭受精度損失且不支援訓練；要麼依據數字靜态随機存取存儲器（SRAM）的CIM，但受限于大面積制造需求和易失性存儲。

研究組報道了一種使用憶阻器-SRAM CIM融合方案的AI邊緣處理器，可同時利用數字SRAM CIM的高精度和電阻式随機存取存儲器憶阻器CIM的高能效和存儲密度。這也使自适應本地訓練能夠适應個性化特征和使用者環境。

該融合處理器實作了高CIM容量、短喚醒-響應延遲（392微秒）、高峰值能效（77.64 TOPS/W）和穩健的精度（精度損失<0.5%）。這項工作表明，憶阻器技術已經超越了實驗室開發階段，現已具備用于AI邊緣處理器的可制造性。

▲ Abstract：

Artificial intelligence (AI) edge devices prefer employing high-capacity nonvolatile compute-in-memory (CIM) to achieve high energy efficiency and rapid wakeup-to-response with sufficient accuracy. Most previous works are based on either memristor-based CIMs, which suffer from accuracy loss and do not support training as a result of limited endurance, or digital static random-access memory (SRAM)–based CIMs, which suffer from large area requirements and volatile storage. We report an AI edge processor that uses a memristor-SRAM CIM-fusion scheme to simultaneously exploit the high accuracy of the digital SRAM CIM and the high energy-efficiency and storage density of the resistive random-access memory memristor CIM. This also enables adaptive local training to accommodate personalized characterization and user environment. The fusion processor achieved high CIM capacity, short wakeup-to-response latency (392 microseconds), high peak energy efficiency (77.64 teraoperations per second per watt), and robust accuracy (<0.5% accuracy loss). This work demonstrates that memristor technology has moved beyond in-lab development stages and now has manufacturability for AI edge processors.

地球科學Earth Science

A national-scale assessment of land subsidence in China’s major cities

中國主要城市地面沉降的全國範圍評估

▲ 作者：ZURUI AO, XIAOMEI HU, SHENGLI TAO, XIE HU, GUOQUAN WANG, MINGJIA LI, ET AL.

▲ 連結：

https://www.science.org/doi/10.1126/science.adl4366

▲ 摘要：

中國大規模的城市化浪潮可能會受到地面沉降的威脅。

利用星載幹涉合成孔徑雷達測量技術，研究組對2015—2022年中國主要城市的地面沉降進行了系統評估。在被調查的城市土地中，45%的土地每年沉降速度超過3毫米，16%的土地每年沉降速度超過10毫米，分别影響了29%和7%的城市人口。

沉降似乎與地下水抽取和建築物重量等一系列因素有關。到2120年，由于城市沉降和海平面上升的綜合影響，22%~26%中國沿海土地的相對海拔将低于海平面，占沿海人口的9%~11%。

該研究結果強調了加強保護措施以減輕沉降造成潛在損害的必要性。

▲ Abstract：

China’s massive wave of urbanization may be threatened by land subsidence. Using a spaceborne synthetic aperture radar interferometry technique, we provided a systematic assessment of land subsidence in all of China’s major cities from 2015 to 2022. Of the examined urban lands, 45% are subsiding faster than 3 millimeters per year, and 16% are subsiding faster than 10 millimeters per year, affecting 29 and 7% of the urban population, respectively. The subsidence appears to be associated with a range of factors such as groundwater withdrawal and the weight of buildings. By 2120, 22 to 26% of China’s coastal lands will have a relative elevation lower than sea level, hosting 9 to 11% of the coastal population, because of the combined effect of city subsidence and sea-level rise. Our results underscore the necessity of enhancing protective measures to mitigate potential damages from subsidence.