《科学》（20230407出版）一周论文导读
2023/4/9 20:20:09 科学网
编译 | 冯维维
Science,7 APR 2023, VOLUME 380, ISSUE 6640
《科学》2023年4月7日，第380卷 6640期
物理学Physics
Tomography of Feshbach resonance states
费什巴赫共振态的层析成像
▲ 作者：BARUCH MARGULIS, KARL P. HORN, DANIEL M. REICH, MEENU UPADHYAY, NITZAN KAHN, ARTHUR CHRISTIANEN, AD VAN DER AVOIRD, GERRIT C. GROENENBOOM, CHRISTIANE P. KOCH, AND EDVARDAS NAREVICIUS
▲ 链接：
https://www.science.org/doi/10.1126/science.adf9888
▲ 摘要：
费什巴赫共振是粒子间相互作用的基础，在与原子、离子和分子的冷碰撞中尤其重要。研究者提出了在强相互作用和高各向异性碰撞的基准系统中检测费什巴赫共振：分子氢离子与惰性气体原子碰撞。碰撞是由冷彭宁电离发起的，只产生费什巴赫共振，跨越相互作用势的短期和长期部分。
研究者利用离子电子符合检测，以层析的方式解析了所有最终的分子通道。他们证明了最终态分布的非统计性质。通过对从头算势能表面进行量子散射计算，研究者证明了费什巴赫共振路径的隔离揭示了它们在碰撞结果中的独特指纹。
▲ Abstract：
Feshbach resonances are fundamental to interparticle interactions and become particularly important in cold collisions with atoms, ions, and molecules. In this work, we present the detection of Feshbach resonances in a benchmark system for strongly interacting and highly anisotropic collisions: molecular hydrogen ions colliding with noble gas atoms. The collisions are launched by cold Penning ionization, which exclusively populates Feshbach resonances that span both short- and long-range parts of the interaction potential. We resolved all final molecular channels in a tomographic manner using ion-electron coincidence detection. We demonstrate the nonstatistical nature of the final-state distribution. By performing quantum scattering calculations on ab initio potential energy surfaces, we show that the isolation of the Feshbach resonance pathways reveals their distinctive fingerprints in the collision outcome.
Extreme ultraviolet metalens by vacuum guiding
真空引导的极紫外超构透镜
▲ 作者：MARCUS OSSIANDER, MARYNA LEONIDIVNA MERETSKA, HANA KRISTIN HAMPEL, SOON WEI DANIEL LIM, NICO KNEFZ, THOMAS JAUK, FEDERICO CAPASSO, AND MARTIN SCHULTZE
▲ 链接：
https://www.science.org/doi/10.1126/science.adg6881
▲ 摘要：
极紫外(EUV)辐射是材料科学、阿秒计量学和光刻技术的关键技术。研究者通过实验证明了超表面是聚焦EUV光的一种优越方式。这些器件利用了硅膜上的孔具有比周围材料大得多的折射率这一事实，并有效地通过真空引导波长为~50纳米的光。这使得纳米级的传输相位可以由孔直径控制。
研究者制造了一个具有10毫米焦距的EUV超透镜，支持高达0.05的数值孔径，并使用它将高谐波产生的超短EUV光爆发聚焦到0.7微米的腰部。该方法引入了介电超表面为缺乏透射光学材料的光谱体系提供的巨大的光塑造可能性。
▲ Abstract：
Extreme ultraviolet (EUV) radiation is a key technology for material science, attosecond metrology, and lithography. Here, we experimentally demonstrate metasurfaces as a superior way to focus EUV light. These devices exploit the fact that holes in a silicon membrane have a considerably larger refractive index than the surrounding material and efficiently vacuum-guide light with a wavelength of ~50 nanometers. This allows the transmission phase at the nanoscale to be controlled by the hole diameter. We fabricated an EUV metalens with a 10-millimeter focal length that supports numerical apertures of up to 0.05 and used it to focus ultrashort EUV light bursts generated by high-harmonic generation down to a 0.7-micrometer waist. Our approach introduces the vast light-shaping possibilities provided by dielectric metasurfaces to a spectral regime that lacks materials for transmissive optics.
化学Chemistry
Overcoming the limitations of Kolbe coupling with waveform-controlled electrosynthesis
克服科尔伯耦合与波形控制电合成的局限性
▲ 作者：YUTA HIOKI, MATTEO COSTANTINI, JEREMY GRIFFIN, KAID C. HARPER, MELANIA PRADO MERINI, BENEDIKT NISSL, YU KAWAMATA , AND PHIL S. BARAN
▲ 链接：
https://www.science.org/doi/10.1126/science.adf4762
▲ 摘要：
科尔伯反应通过电化学脱羧偶联形成碳碳键。尽管已有一个多世纪的研究，但由于极差的化学选择性和对贵金属电极的依赖，该反应的应用范围有限。研究者为这一长期挑战提出了一个简单的解决方案：将电位波形从经典直流电切换到快速交替极性，使各种官能团兼容，并使可持续的碳基电极(非晶碳)上的反应成为可能。
这一突破使他们能够获得有价值的分子，包括从有用的非天然氨基酸到有前途的聚合物构建块，这些分子都来自现成的羧酸，包括生物质衍生的酸。初步的机理研究展示了波形在调节电极周围局部pH值中的作用，以及丙酮作为非常规反应溶剂在科尔伯反应中的关键作用。
▲ Abstract：
The Kolbe reaction forms carbon-carbon bonds through electrochemical decarboxylative coupling. Despite more than a century of study, the reaction has seen limited applications owing to extremely poor chemoselectivity and reliance on precious metal electrodes. In this work, we present a simple solution to this long-standing challenge: Switching the potential waveform from classical direct current to rapid alternating polarity renders various functional groups compatible and enables the reaction on sustainable carbon-based electrodes (amorphous carbon). This breakthrough enabled access to valuable molecules that range from useful unnatural amino acids to promising polymer building blocks from readily available carboxylic acids, including biomass-derived acids. Preliminary mechanistic studies implicate the role of waveform in modulating the local pH around the electrodes and the crucial role of acetone as an unconventional reaction solvent for Kolbe reaction.
Formation of active sites on transition metals through reaction-driven migration of surface atoms
表面原子迁移在过渡金属上形成活性位点
▲ 作者：LANG XU, KONSTANTINOS G. PAPANIKOLAOU, BARBARA A. J. LECHNER, LISA JE, GABOR A. SOMORJAI, MIQUEL SALMERON, AND MANOS MAVRIKAKIS
▲ 链接：
https://www.science.org/doi/10.1126/science.add0089
▲ 摘要：
在多相催化中，人们通常认为吸附剂在低温和低压下对表面金属原子之间的键合影响很小。研究者利用密度泛函理论，找到了吸附分子通过破坏表面键来清除过渡金属原子的条件。这些原子可以形成簇，他们使用动力学蒙特卡罗模拟来阐明一氧化碳诱导的铜表面簇的形成过程。
扫描隧道显微镜在含有台阶和位错的镍(111)表面上的一氧化碳说明了这种现象的结构敏感性。研究表明，几种催化体系的反应机制可能由原位吸附诱导活性位点的形成所主导，在现实反应条件下导致催化剂结构演变的金属-金属键断裂发生的范围比以前想象的要广泛得多。
▲ Abstract：
In heterogeneous catalysis, it is often assumed that adsorbates have minimal effects on the bonding between surface metal atoms at low temperatures and pressures. Xu et al. used density functional theory to find conditions in which adsorbed molecules can scavenge transition metal atoms by breaking bonds at the surface. These atoms can then form clusters, as observed in kinetic Monte Carlo simulations of carbon monoxide on copper and in scanning tunneling microscopy studies of carbon monoxide on a Ni(111) surface containing steps and dislocations. The reaction mechanisms of several catalytic systems may be dominated by in situ adsorbate-induced active site formation.
Chemically circular, mechanically tough, and melt-processable polyhydroxyalkanoates
可熔融加工的聚羟基烷酸酯
▲ 作者：LI ZHOU, ZHEN ZHANG, CHANGXIA SHI, MIRIAM SCOTI, DEEPAK K. BARANGE, RAVIKUMAR R. GOWDA, AND EUGENE Y.-X. CHEN
▲ 链接：
https://www.science.org/doi/10.1126/science.adg4520
▲ 摘要：
聚羟基烷酸酯是一种很有前途的塑料，可以通过化学或微生物方法从相对可持续的原料中获得。然而，它们的性能落后于商业石油化学衍生替代品。
研究者用甲基取代单体中活性羰基邻近的氢，可产生在多个方面都更稳健的聚羟基烷酸酯。这种二甲基聚合物具有结晶性和延展性，在熔体处理过程中结构良好，并且在与碱处理时可以有效降解以回收单体。
▲ Abstract：
Polyhydroxyalkanoates are a promising class of plastics accessible chemically or microbially from relatively sustainable feedstocks. However, their performance properties lag behind commercial petrochemically derived alternatives. Zhou et al. report that replacing reactive carbonyl-adjacent hydrogens in the monomer with methyl groups produces a polyhydroxyalkanoate that is more robust in multiple respects. The dimethyl polymer is both crystalline and ductile, structurally sound during melt processing, and subject to efficient degradation to recover the monomer on treatment with base.
Lead zirconate titanate ceramics with aligned crystallite grains
具有排列晶粒的锆钛酸铅陶瓷
▲ 作者：JINGLEI LI, WANBO QU, JOHN DANIELS, HAIJUN WU, LINJING LIU, JIE WU, MINGWEN WANG, STEFANO CHECCHIA, SHUAI YANG, AND FEI LI
▲ 链接：
https://www.science.org/doi/10.1126/science.adf6161
▲ 摘要：
锆钛酸铅压电对于制造换能器、传感器和机电应用的其他组件非常重要。为了扩大可用温度范围和机电耦合因子，作者引入了锆钛酸铅基材料的织构工艺。牺牲模板既改变了固溶体的组成，又使晶体定向，从而提高了压电性能。
▲ Abstract：
Lead zirconate titanate piezoelectrics are important for making transducers, sensors, and other components for electromechanical applications. To expand the usable temperature range and electromechanical coupling factor, Li et al. introduce a texturing process for lead zirconate titanate–based materials. A sacrificial template both changes the composition of the solid solution and orients the crystals to improve the piezoelectric properties.
编辑 | 方圆
排版 | 郭刚
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