2023/5/29 8:49:55 阅读：61 发布者：
Science, 19 May 2023, Volume 380, Issue 6646
《科学》2023年5月19日，第380卷，6646期
物理学Physics
Entangling microwaves with light
微波与光的纠缠
▲ 作者：R. SAHU , L. QIU, W. HEASE, G. ARNOLD, Y. MINOGUCHI, P. RABL, AND J. M. FINK
▲ 链接：
https://www.science.org/doi/10.1126/science.adg3812
▲ 摘要：
目前正在开发用于量子计算、模拟和计量应用的几个平台，每个平台在不同的工作波长下工作，以优化性能。对于实际技术而言，现实可能是一个混合平台，需要在具有巨大能量差异的平台上生成和共享量子纠缠。
作者介绍了一种电光器件，可以在微波（超导电路的工作波长）与光子（远距离量子通信的工作波长）之间产生量子纠缠。能量尺度差异超过5个数量级的桥接平台并保持脆弱的纠缠为有效连接混合量子系统提供了一条途径。
▲ Abstract：
Several platforms are under development for quantum computation, simulation, and metrology applications, with each platform operating at different operational wavelengths for optimized performance. For practical technologies, the reality will likely be a hybrid of platforms that require quantum entanglement to be generated and shared across platforms with a large energy disparity. Sahu et al. introduce an electro-optical device that allows the generation of quantum entanglement between microwaves (the operational wavelengths of superconducting circuits) with optical photons (the operational wavelength of long-distance quantum communication). Bridging platforms with more than five orders of magnitude difference in energy scales and maintaining the fragile entanglement provides a route to efficiently linking up hybrid quantum systems.
High-performance multimode elastocaloric cooling system
高性能多模弹性热冷却系统
▲ 作者：SUXIN QIAN, DAVID CATALINI, JAN MUEHLBAUER, BOYANG LIU, HET MEVADA, HUILONG HOU, YUNHO HWANG, REINHARD RADERMACHER, AND ICHIRO TAKEUCHI
▲ 链接：
https://www.science.org/doi/10.1126/science.adg7043
▲ 摘要：
蒸汽压缩冷却通常依赖于温室气体或具有可燃性和毒性的其他问题的制冷剂。热量冷却是一种不同的策略，它依赖于通过相变移动固体。
研究者开发了一种弹性热冷却装置，通过压缩耐疲劳的镍钛管束来获得有吸引力的冷却功率和最大温差。该装置相对于其他热量策略具有竞争力，并可能最终商业化。
▲ Abstract：
Vapor compression cooling often relies on refrigerants that are greenhouse gases or have other issues with flammability and toxicity. Caloric cooling is a different strategy that instead relies on moving solids through a phase transition. Qian et al. developed an elastocaloric cooling device that compresses fatigue-resistant bundles of nickel–titanium tubes to obtain an attractive cooling power and maximum temperature difference. The device is competitive relative to other caloric strategies and may be attractive for eventual commercialization.
化学Chemistry
Generality-oriented optimization of enantioselective aminoxyl radical catalysis
对映选择性氨基自由基催化的一般性优化
▲ 作者：JONAS REIN, SOREN D. ROZEMA, OLIVIA C. LANGNER, SAMSON B. ZACATE, MELISSA A. HARDY, JUNO C. SIU, BRANDON Q. MERCADO, MATTHEW S. SIGMAN , SCOTT J. MILLER , AND SONG LIN
▲ 链接：
https://www.science.org/doi/10.1126/science.adf6177
▲ 摘要：
当化学家优化催化剂时，他们通常在测试反应中使用单一底物。然后，用该底物产生最佳结果的催化剂被应用于更广泛的底物。
作者报告了一种不同的方法：在不同底物池上同时筛选催化剂，目的是优化整个池的中位对映体选择性。利用这种方法对肽取代氨基氧基框架进行结构修饰，有效地确定了一种广泛通用的二元醇氧化去对称催化剂。
▲ Abstract：
When chemists optimize catalysts, they typically work with a single substrate in a test reaction. Then, the catalyst producing the best outcome with that substrate is applied to a broader range of substrates. Rein et al. report a different approach: screening catalysts concurrently on a diverse pool of substrates with the aim of optimizing median enantioselectivity across the pool. Structural modification of a peptide-substituted aminoxyl radical framework using this method efficiently pinpointed a broadly versatile catalyst for the oxidative desymmetrization of diols.
Disentangling the activity-selectivity trade-off in catalytic conversion of syngas to light olefins
合成气催化转化为轻烯烃的活性-选择性权衡解耦
▲ 作者：FENG JIAO, BING BAI, GEN LI, XIULIAN PAN, YIHAN YE, SHENGCHENG QU, CHANGQI XU, JIANPING XIAO, ZHENGHAO JIA , AND XINHE BAO
▲ 链接：
https://www.science.org/doi/10.1126/science.adg2491
▲ 摘要：
由氢和一氧化碳的混合物（合成气）在金属氧化物沸石催化剂上生产轻烯烃，由于副反应相互竞争而变得复杂。
研究表明，在沸石AlPO-18中，通过锗取代产生的Brønsted酸位点对中间体与烯烃的碳-碳偶联非常活跃，但对加氢和烯烃低聚的不需要的尺寸反应却要弱得多。一氧化碳转化率为85%，轻烯烃选择性为83%，总收率接近50%。
▲ Abstract：
The production of light olefins from a mixture of hydrogen and carbon monoxide (syngas) over metal-oxide zeolite catalysts is complicated by competing side reactions. Jiao et al. show that the Brønsted acid sites created in the zeolite AlPO-18 by germanium substitution were highly active for carbon–carbon coupling of the intermediates to olefins but much weaker for the unwanted size reactions of hydrogenation and olefin oligomerization. A carbon monoxide conversion of 85%, along with a selectivity of for light olefins of 83%, led to an overall yield of almost 50%.
环境科学
Environmental Science
Satellites reveal widespread decline in global lake water storage
卫星显示全球湖泊储水量普遍下降
▲ 作者：FANGFANG YAO, BEN LIVNEH, BALAJI RAJAGOPALAN, JIDA WANG, JEAN-FRANÇOIS CRÉTAUX, YOSHIHIDE WADA, AND MURIEL BERGE-NGUYEN
▲ 链接：
https://www.science.org/doi/10.1126/science.abo2812
▲ 摘要：
气候变化和人类活动日益威胁到储存着地球表面87%液态淡水的湖泊。然而，在全球范围内，湖泊体积变化的最新趋势和驱动因素在很大程度上仍然未知。
研究者利用30年的卫星观测、气候数据和水文模型分析了1972年全球最大的湖泊，发现在1992年至2020年期间，53%的这些水体的存储量在统计上显著下降。自然湖泊的净体积损失主要归因于气候变暖、蒸发需求增加和人类用水，而水库的储存损失主要是沉积。
他们估计，全球约有1/4的人口居住在干涸的湖泊流域，这强调了将气候变化和沉积影响纳入可持续水资源管理的必要性。
▲ Abstract：
Climate change and human activities increasingly threaten lakes that store 87% of Earth’s liquid surface fresh water. Yet, recent trends and drivers of lake volume change remain largely unknown globally. Here, we analyze the 1972 largest global lakes using three decades of satellite observations, climate data, and hydrologic models, finding statistically significant storage declines for 53% of these water bodies over the period 1992–2020. The net volume loss in natural lakes is largely attributable to climate warming, increasing evaporative demand, and human water consumption, whereas sedimentation dominates storage losses in reservoirs. We estimate that roughly one-quarter of the world’s population resides in a basin of a drying lake, underscoring the necessity of incorporating climate change and sedimentation impacts into sustainable water resources management.
Releasing global forests from human management: How much more carbon could be stored?
全球森林还能储存多少碳？
▲ 作者：CASPAR T. J. ROEBROEK, GREGORY DUVEILLER, SONIA I. SENEVIRATNE, EDOUARD L. DAVIN, AND ALESSANDRO CESCATTI
▲ 链接：
https://www.science.org/doi/10.1126/science.add5878
▲ 摘要：
森林碳储存是防止全球变暖超过1.5°C的政策制定的基石。然而，管理措施（例如采伐）对森林碳收支的全球影响仍然缺乏量化。
研究者将森林生物量和管理的全球地图与机器学习相结合，表明在当前的气候条件和二氧化碳浓度下，通过消除人为干预，现有的全球森林可以增加高达44.1（误差范围：21.0至63.0）亿吨碳。这比目前的水平增加了15%到16%，相当于目前4年的人为二氧化碳排放量。
因此，如果不大力减少排放，这一战略的缓解潜力就很低，应保留森林汇以抵消剩余的碳排放，而不是补偿目前的排放水平。
▲ Abstract：
Carbon storage in forests is a cornerstone of policy-making to prevent global warming from exceeding 1.5°C. However, the global impact of management (for example, harvesting) on the carbon budget of forests remains poorly quantified. We integrated global maps of forest biomass and management with machine learning to show that by removing human intervention, under current climatic conditions and carbon dioxide (CO2) concentration, existing global forests could increase their aboveground biomass by up to 44.1 (error range: 21.0 to 63.0) petagrams of carbon. This is an increase of 15 to 16% over current levels, equating to about 4 years of current anthropogenic CO2 emissions. Therefore, without strong reductions in emissions, this strategy holds low mitigation potential, and the forest sink should be preserved to offset residual carbon emissions rather than to compensate for present emissions levels.
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