等期刊一周论文导读

编译 | 未玖

Nature , 14 April 2022, VOL 604, ISSUE 7905

《自然》 2022年4月14日，第604卷，7905期

天文学 Astronomy

A dusty compact object bridging galaxies and quasars at cosmic dawn

在宇宙黎明时分，星系由尘埃致密体过渡到类星体

作者：S. Fujimoto, G. B. Brammer, D. Watson, G. E. Magdis, V. Kokorev, T. R. Greve, et al.

链接：

摘要：

自从发现发光类星体在宇宙大爆炸后仅存在7亿年以来，了解超大质量黑洞在早期宇宙中如何形成和生长已成为一个重大难题。

理论模拟显示了一种进化序列，尘埃红移的类星体从严重尘埃遮蔽的星暴星系中出现，然后通过释放气体和尘埃过渡到无遮蔽的发光类星体。尽管最后一个阶段的红移已被确定为，但由于它们在光学和近红外波长上的微弱性，目前尚未发现具有类似红移的过渡类星体。

研究组报道了一个紫外致密天体GNz7q的观测结果，它与一个红移为   、尘埃掩蔽的星暴有关。

在该时期，宿主星系的尘埃辐射比任何其他已知物体都要明亮，在480秒差距的中心半径范围内，每年形成1600个太阳质量的恒星。在深部、高分辨率成像和无狭缝光谱中，可识别出一个远紫外的红点源。

GNz7q在X射线中非常微弱，这表明在尘埃星暴核心出现了一个独特的紫外致密恒星形成区或一个康普顿厚、超过爱丁顿极限的黑洞吸积盘。在后一种情况下，观测到的性质与宇宙学模拟的预测一致，并表明GNz7q是晚期无遮蔽发光类星体的祖先。

Abstract：

Understanding how super-massive black holes form and grow in the early Universe has become a major challenge since it was discovered that luminous quasars existed only 700 million years after the Big Bang. Simulations indicate an evolutionary sequence of dust-reddened quasars emerging from heavily dust-obscured starbursts that then transition to unobscured luminous quasars by expelling gas and dust. Although the last phase has been identified out to a redshift of , a transitioning quasar has not been found at similar redshifts owing to their faintness at optical and near-infrared wavelengths. Here we report observations of an ultraviolet compact object, GNz7q, associated with a dust-enshrouded starburst at a redshift of    . The host galaxy is more luminous in dust emission than any other known object at this epoch, forming 1,600 solar masses of stars per year within a central radius of 480 parsec. A red point source in the far-ultraviolet is identified in deep, high-resolution imaging and slitless spectroscopy. GNz7q is extremely faint in X-rays, which indicates the emergence of a uniquely ultraviolet compact star-forming region or a Compton-thick super-Eddington black-hole accretion disk at the dusty starburst core. In the latter case, the observed properties are consistent with predictions from cosmological simulations and suggest that GNz7q is an antecedent to unobscured luminous quasars at later epochs.

物理学 Physics

Intelligent infrared sensing enabled by tunable moiré quantum geometry

可调谐莫尔量子几何实现智能红外传感

作者：Chao Ma, Shaofan Yuan, Patrick Cheung, Kenji Watanabe, Takashi Taniguchi, Fan Zhang, et al.

链接：

摘要：

众所周知，固体中布洛赫波函数的量子几何性质，即贝里曲率和量子度量，显著影响着电子的基态和激发态行为。

体光伏效应（BPVE）是一种依赖于激发光偏振的非线性现象，在很大程度上取决于光学跃迁中的量子几何特性。红外BPVE尚未在石墨烯或莫尔体系等新兴平台中观察到，尽管这些平台已报道过与量子几何有关的激发强关联现象。

研究组报道了在扭曲双双层石墨烯（TDBG）中观察到5 µm和 µm处可调谐中红外BPVE，由莫尔诱导的强对称性破缺和量子几何贡献产生。光响应在很大程度上取决于激发光的偏振态，且可通过外部电场进行高度调谐。

这种量子几何特性的广泛可调性使研究组能够使用卷积神经网络同时实现全斯托克斯偏振测量和波长检测，仅使用一个亚波长足迹仅为3  3  µm2的TDBG器件 。

该研究工作不仅揭示了莫尔工程量子几何在可调谐非线性光-物质相互作用中的独特作用，还以极其紧凑的芯片方式为未来智能传感技术开辟了新途径。

Abstract：

Quantum geometric properties of Bloch wave functions in solids, that is, Berry curvature and the quantum metric, are known to significantly influence the ground- and excited-state behaviour of electrons. The bulk photovoltaic effect (BPVE), a nonlinear phenomenon depending on the polarization of excitation light, is largely governed by the quantum geometric properties in optical transitions. Infrared BPVE has yet to be observed in graphene or moiré systems, although exciting strongly correlated phenomena related to quantum geometry have been reported in this emergent platform. Here we report the observation of tunable mid-infrared BPVE at 5 µm and  µm in twisted double bilayer graphene (TDBG), arising from the moiré-induced strong symmetry breaking and quantum geometric contribution. The photoresponse depends substantially on the polarization state of the excitation light and is highly tunable by external electric fields. This wide tunability in quantum geometric properties enables us to use a convolutional neural network to achieve full-Stokes polarimetry together with wavelength detection simultaneously, using only one single TDBG device with a subwavelength footprint of merely 3   3 µm2. Our work not only reveals the unique role of moiré engineered quantum geometry in tunable nonlinear light–matter interactions but also identifies a pathway for future intelligent sensing technologies in an extremely compact, on-chip manner.

材料科学 Materials Science

Uniting tensile ductility with ultrahigh strength via composition undulation

通过成分起伏同时实现拉伸塑性与超高强度

作者：Heng Li, Hongxiang Zong, Suzhi Li, Shenbao Jin, Yan Chen, Matthew J. Cabral, et al.

链接：

摘要：

具有纳米晶粒的金属有接近2 GPa的超高强度。然而，这种极端的晶界强化导致几乎所有拉伸塑性的丧失，即使当金属具有面心立方结构（所有晶体结构中塑性最强的结构）时亦如此。

研究组证明了纳米晶镍-钴固溶体虽仍是面心立方单相，但其拉伸强度约为  GPa，塑性断裂伸长率约为16 %。

这种不寻常的拉伸强度和塑性的结合是通过高浓度固溶体中的成分起伏实现的。这种起伏使得层错能和晶格应变在1-10纳米的尺度范围内发生空间变化，从而显著影响了位错运动。

尽管纳米晶粒内部空间非常有限，但位错运动变得缓慢，促进了它们的交互作用、联锁和增殖。因此，流动应力增加，同时位错储存增加，从而提升了应变硬化能力，提高了塑性。

同时，沿位错线的分段脱捕需要较小的激活体积，因此应变速率敏感性增加，这也稳定了拉伸流动。因此，抗位错传播的起伏结构提供了一种强化机制，可在高流动应力下保持拉伸塑性。

Abstract：

Metals with nanocrystalline grains have ultrahigh strengths approaching two gigapascals. However, such extreme grain-boundary strengthening results in the loss of almost all tensile ductility, even when the metal has a face-centred-cubic structure—the most ductile of all crystal structures. Here we demonstrate that nanocrystalline nickel–cobalt solid solutions, although still a face-centred-cubic single phase, show tensile strengths of about  gigapascals with a respectable ductility of about 16 per cent elongation to failure. This unusual combination of tensile strength and ductility is achieved by compositional undulation in a highly concentrated solid solution. The undulation renders the stacking fault energy and the lattice strains spatially varying over length scales in the range of one to ten nanometres, such that the motion of dislocations is thus significantly affected. The motion of dislocations becomes sluggish, promoting their interaction, interlocking and accumulation, despite the severely limited space inside the nanocrystalline grains. As a result, the flow stress is increased, and the dislocation storage is promoted at the same time, which increases the strain hardening and hence the ductility. Meanwhile, the segment detrapping along the dislocation line entails a small activation volume and hence an increased strain-rate sensitivity, which also stabilizes the tensile flow. As such, an undulating landscape resisting dislocation propagation provides a strengthening mechanism that preserves tensile ductility at high flow stresses.

Perovskite–organic tandem solar cells with indium oxide interconnect

钙钛矿-氧化铟互连有机串联太阳能电池

作者：K. O. Brinkmann, T. Becker, F. Zimmermann, C. Kreusel, T. Gahlmann, M. Theisen, et al.

链接：

摘要：

多结太阳能电池可以克服单结器件的基本效率限制。金属卤化物钙钛矿型太阳能电池的带隙可调性使其在多结结构中具有吸引力。硅和铜铟硒化镓（CIGS）以及全钙钛矿串联电池的组合已有报道。与此同时，窄间隙非富勒烯受体为有机太阳能电池带来了快速提升的效率。

有机和钙钛矿半导体是一种很有吸引力的组合，具有相似的加工技术。目前，钙钛矿-有机串联电池的效率低于标准，并且受到宽间隙钙钛矿电池的低开路电压（Voc）和子电池之间互连引入损耗的限制。

研究组展示了钙钛矿-有机串联电池的效率为（认证为），Voc高达 伏特。优化的电荷提取层使钙钛矿子电池具有高Voc和填充因子的出色组合。

该串联电池的有机子电池在近红外下提供了高外部量子效率，与对非富勒烯电池有限光稳定性的典型担忧相反，如果激子主要在非富勒烯受体上产生，则表现出出色的操作稳定性。子电池由一层超薄（约纳米）类金属氧化铟层连接，具有前所未有的低光/电损耗。

这项工作为钙钛矿-有机串联电池竖了一座里程碑，它优于最好的p–i–n钙钛矿单结，并与钙钛矿-CIGS和所有钙钛矿多结相媲美。

Abstract：

Multijunction solar cells can overcome the fundamental efficiency limits of single-junction devices. The bandgap tunability of metal halide perovskite solar cells renders them attractive for multijunction architectures. Combinations with silicon and copper indium gallium selenide (CIGS), as well as all-perovskite tandem cells, have been reported. Meanwhile, narrow-gap non-fullerene acceptors have unlocked skyrocketing efficiencies for organic solar cells. Organic and perovskite semiconductors are an attractive combination, sharing similar processing technologies. Currently, perovskite–organic tandems show subpar efficiencies and are limited by the low open-circuit voltage (Voc) of wide-gap perovskite cells and losses introduced by the interconnect between the subcells. Here we demonstrate perovskite–organic tandem cells with an efficiency of per cent (certified per cent) and a high Voc of  volts. Optimized charge extraction layers afford perovskite subcells with an outstanding combination of high Voc and fill factor. The organic subcells provide a high external quantum efficiency in the near-infrared and, in contrast to paradigmatic concerns about limited photostability of non-fullerene cells, show an outstanding operational stability if excitons are predominantly generated on the non-fullerene acceptor, which is the case in our tandems. The subcells are connected by an ultrathin (approximately  nanometres) metal-like indium oxide layer with unprecedented low optical/electrical losses. This work sets a milestone for perovskite–organic tandems, which outperform the best p–i–n perovskite single junctions and are on a par with perovskite–CIGS and all-perovskite multijunctions.

机械工程 Mechanical Engineering

Thermophotovoltaic efficiency of 40%

科学家实现40%的热光伏效率

作者：Alina LaPotin, Kevin L. Schulte, Myles A. Steiner, Kyle Buznitsky, Colin C. Kelsall, Daniel J. Friedman, et al.

链接：

摘要：

热光伏（TPV）主要通过光伏效应将红外波长的光转换为电能，可使用比目前普遍存在于电力生产中的涡轮机更高温度的热源进行能量存储和转换。

自从在2000 下使用集成背表面反射器和钨发射极首次展示29%的高效TPV以来，TPV的制造和性能得到了改善。然而，尽管预测TPV的效率可能超过50%，但在温度低于1300 下，实际效率仍仅为32%。

研究组报道了效率超过40%的TPV电池的制造和测量，并通过实验证明了高带隙串联TPV电池的效率。TPV电池是由带隙在 eV的III–V材料组成的双结器件，针对1900-2400 的发射极温度进行了优化。

电池利用带边光谱滤波的概念来获得高效率，使用高反射背表面反射器来拒绝不可用的子带隙辐射返回发射极。在功率密度为 W cm –2 ，发射极温度为2400 的条件下， eV器件的最大效率为（   1）%。在功率密度为 W cm–2，发射极温度为2127 的条件下， eV器件的最大效率为（   1）%。

这些电池可以集成到一个TPV系统中，用于热能电网存储，以实现可调度的可再生能源。这为热能电网存储创造了一条途径，以达到足够高的效率和足够低的成本，从而实现电网脱碳。

Abstract：

Thermophotovoltaics (TPVs) convert predominantly infrared wavelength light to electricity via the photovoltaic effect, and can enable approaches to energy storage and conversion that use higher temperature heat sources than the turbines that are ubiquitous in electricity production today. Since the first demonstration of 29% efficient TPVs using an integrated back surface reflector and a tungsten emitter at 2,000  C, TPV fabrication and performance have improved. However, despite predictions that TPV efficiencies can exceed 50%, the demonstrated efficiencies are still only as high as 32%, albeit at much lower temperatures below 1,300  C. Here we report the fabrication and measurement of TPV cells with efficiencies of more than 40% and experimentally demonstrate the efficiency of high-bandgap tandem TPV cells. The TPV cells are two-junction devices comprising III–V materials with bandgaps between and eV that are optimized for emitter temperatures of 1,900–2,400  C. The cells exploit the concept of band-edge spectral filtering to obtain high efficiency, using highly reflective back surface reflectors to reject unusable sub-bandgap radiation back to the emitter. A eV device reached a maximum efficiency of (   1)% operating at a power density of  W cm–2 and an emitter temperature of 2,400  C. A eV device reached a maximum efficiency of (   1)% operating at a power density of  W cm –2 and an emitter temperature of 2,127  C. These cells can be integrated into a TPV system for thermal energy grid storage to enable dispatchable renewable energy. This creates a pathway for thermal energy grid storage to reach sufficiently high efficiency and sufficiently low cost to enable decarbonization of the electricity grid.

地球科学 Earth Science

Realization of Paris Agreement pledges may limit warming just below 2

实现《巴黎协定》的承诺有望将全球变暖控制在2 以下

作者：Malte Meinshausen, Jared Lewis, Christophe McGlade, Johannes Gütschow, Zebedee Nicholls, Rebecca Burdon, et al.

链接：

摘要：

在《格拉斯哥气候公约》签署前的过去五年中，154个缔约方在其国家自主贡献中提交了新的或更新的2030年减缓目标，76个缔约方提出了长期承诺。对2021联合国气候变化大会（COP26）之前承诺的量化表明，将升温控制在2 以下的可能性低于50 %。

研究组证明，如果所有有条件和无条件的承诺都得到充分和及时的执行，全球变暖可以控制在2  以下。根据政府间气候变化专门委员会（IPCC）第六次评估报告中第一工作组对地球系统不确定性进行的概率表征，在全面执行的情况下，峰值升温可被限制在  之间。

研究组回顾性地预测了21世纪的气候变暖，以显示2015-2021年雄心勃勃的总体目标水平如何变化。研究结果依赖于对2030年或2050年之后的限时目标外推、IPCC 特别报告（）情景数据库的特征和承诺的全面实施情况。

对这些因素更悲观的假设将导致更高的升温预测。另一个独立的排放模型框架预测，全球升温峰值为 ，这支持了该研究发现，即各国兑现承诺可能会将全球变暖限制在略低于2 的范围内。

若不仅要将升温控制在“略低于”，还要控制在“远低于”2  或 ，则迫切需要制定政策和采取行动，以在本世纪中叶实现全球C O2 净零排放。

Abstract：

Over the last five years prior to the Glasgow Climate Pact, 154 Parties have submitted new or updated 2030 mitigation goals in their nationally determined contributions and 76 have put forward longer-term pledges. Quantifications of the pledges before the 2021 United Nations Climate Change Conference (COP26) suggested a less than 50 per cent chance of keeping warming below 2 degrees Celsius. Here we show that warming can be kept just below 2 degrees Celsius if all conditional and unconditional pledges are implemented in full and on time. Peak warming could be limited to – degrees Celsius in the full implementation case—building on a probabilistic characterization of Earth system uncertainties in line with the Working Group I contribution to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). We retrospectively project twenty-first-century warming to show how the aggregate level of ambition changed from 2015 to 2021. Our results rely on the extrapolation of time-limited targets beyond 2030 or 2050, characteristics of the IPCC   C Special Report () scenario database and the full implementation of pledges. More pessimistic assumptions on these factors would lead to higher temperature projections. A second, independent emissions modelling framework projected peak warming of  degrees Celsius, supporting the finding that realized pledges could limit warming to just below 2 degrees Celsius. Limiting warming not only to ‘just below’ but to ‘well below’ 2 degrees Celsius or  degrees Celsius urgently requires policies and actions to bring about steep emission reductions this decade, aligned with mid-century global net-zero C O2 emissions

编译 | 李言

Nature , 28 April 2022, Volume 604 Issue 7907

《自然》 2022年4月28日，第604卷，7907期

天文学 Astronomy

Early Solar System instability triggered by dispersal of the gaseous disk

气体盘的耗散触发早期太阳系的不稳定性

作者：Beibei Liu, Sean N. Raymond & Seth A. Jacobson

链接：

摘要：

在此，我们使用动态模拟表明，巨行星的不稳定性可能是由气体盘的耗散触发的。当气体盘从内到外蒸发时，它的内缘依次扫过并依次动态地扰乱了每颗行星的轨道。相关的轨道移动导致系统外部的动力压缩，最终引发不稳定性。

在天体物理参数的可行范围内，我们模拟系统的最终轨道与太阳系的轨道相匹配。因此，巨大行星的不稳定性发生在气体盘耗散的时候，根据天文观测，这是在太阳系诞生后的几百万年到一千万年间。

类地行星的形成直到如此早期的巨行星不稳定之后才完成；不断增长的类地行星甚至可能是被它的扰动塑造的，这解释了为什么火星相对于地球的质量较小。

Abstract：

Here we use dynamical simulations to show that the giant planets’ instability was probably triggered by the dispersal of the gaseous disk. As the disk evaporated from the inside out, its inner edge swept successively across and dynamically perturbed each planet’s orbit in turn. The associated orbital shift caused a dynamical compression of the exterior part of the system, ultimately triggering instability. The final orbits of our simulated systems match those of the Solar System for a viable range of astrophysical parameters. The giant planet instability therefore took place as the gaseous disk dissipated, constrained by astronomical observations to be a few to ten million years after the birth of the Solar System. Terrestrial planet formation would not complete until after such an early giant planet instability; the growing terrestrial planets may even have been sculpted by its perturbations, explaining the small mass of Mars relative to Earth.

物理学 Physics

Observation of a linked-loop quantum state in a topological magnet

拓扑磁体中链环量子态的观察

作者：Ilya Belopolski, Guoqing Chang, Tyler A. Cochran, Zi-Jia Cheng et al.

链接：

摘要：

在此，我们报告一个与在镜像对称铁磁体中电子带交叉环线相关的不寻常的连接数（扭结理论）不变量。利用最先进的光谱方法，我们直接观察到材料的三环体T3布里渊区中三个纠缠在一起的简并环。

我们发现每个环连接其他环两次。通过系统光谱研究这一链环量子态，我们明确地画出了它的链图，并类比结理论，得出它的链数为(2,2,2)，从实验数据直接确定了它的不变结构。

我们进一步预测和观察了样品表面的塞弗特边界态，该边界态由体链环保护，表明了显著的塞弗特体边界响应。我们对量子环链的观察，推动了扭结理论在 探索 磁性和超导量子物质方面的应用。

Abstract：

Here we report an unusual linking-number (knot theory) invariant associated with loops of electronic band crossings in a mirror-symmetric ferromagnet. Using state-of-the-art spectroscopic methods, we directly observe three intertwined degeneracy loops in the material’s three-torus, T3, bulk Brillouin zone. We find that each loop links each other loop twice. Through systematic spectroscopic investigation of this linked-loop quantum state, we explicitly draw its link diagram and conclude, in analogy with knot theory, that it exhibits the linking number (2, 2, 2), providing a direct determination of the invariant structure from the experimental data. We further predict and observe, on the surface of our samples, Seifert boundary states protected by the bulk linked loops, suggestive of a remarkable Seifert bulk–boundary correspondence. Our observation of a quantum loop link motivates the application of knot theory to the exploration of magnetic and superconducting quantum matter.

The field-free Josephson diode in a van der Waals heterostructure

范德华异质结构中的无磁场约瑟夫森二极管

作者：Heng Wu, Yaojia Wang, Yuanfeng Xu, Pranava K. Sivakumar, Chris Pasco, Ulderico Filippozzi, Stuart S. P. Parkin, Yu-Jia Zeng, Tyrel McQueen & Mazhar N. Ali

链接：

摘要：

在此，我们通过制作NbSe2/Nb3Br8/NbSe2的反转对称破缺范德华异质结构，实现了约瑟夫森二极管。

我们证明，即使没有磁场，结也可以在正电流下超导，同时在负电流下具有电阻性。ΔIc 行为（正和负临界电流之间的差异）与磁场是对称的，约瑟夫逊耦合可以通过夫劳恩霍夫模式证明。

同时，我们以极低的开关电流密度、高整流比和高鲁棒性实现了方波激励的稳定半波整流。这种非互易行为强烈违背了已知的约瑟夫森关系，并为通过量子材料与约瑟夫森结的整合打开了发现新的机制和物理现象的大门，并为超导量子器件提供了新的途径。

Abstract：

Here we realized the Josephson diode by fabricating an inversion symmetry breaking van der Waals heterostructure of NbSe2/Nb3Br8/NbSe2. We demonstrate that even without a magnetic field, the junction can be superconducting with a positive current while being resistive with a negative current. The ΔIc behaviour (the difference between positive and negative critical currents) with magnetic field is symmetric and Josephson coupling is proved through the Fraunhofer pattern. Also, stable half-wave rectification of a square-wave excitation was achieved with a very low switching current density, high rectification ratio and high robustness. This non-reciprocal behaviour strongly violates the known Josephson relations and opens the door to discover new mechanisms and physical phenomena through integration of quantum materials with Josephson junctions, and provides new avenues for superconducting quantum devices.

化学 Chemistry

Machine learning-aided engineering of hydrolases for PET depolymerization

PET降解酶的机器学习辅助工程

作者：Hongyuan Lu, Daniel J. Diaz, Natalie J. Czarnecki, Congzhi Zhu et al.

链接：

摘要：

在此，我们使用一种基于结构的机器学习算法来设计稳定和活跃的PET水解酶。我们的突变组合（FAST-PETase：具有功能性、活性、稳定和耐受性的PETase）与野生型PETase相比含有5个突变，在30 - 50 C和一系列pH水平范围内，与野生型和工程替代品相比，显示了优越的pet水解活性。

我们证明，来自51种消费者使用过的PET几乎都可以在1周内被FAST-PETase完全降解。FAST-PETase可以在50ºC下解聚商业水瓶和整个热预处理水瓶的未处理的无定形部分。

最后，我们通过利用FAST-PETase和回收的单体重新合成PET，展示了一个闭环PET回收过程。总而言之，我们的结果展示了一条工业化规模的酶塑料回收的可行途径。

Abstract：

Here, we use a structure-based, machine learning algorithm to engineer a robust and active PET hydrolase. Our mutant and scaffold combination (FAST-PETase: functional, active, stable and tolerant PETase) contains five mutations compared to wild-type PETase (N233K/R224Q/S121E from prediction and D186H/R280A from scaffold) and shows superior PET-hydrolytic activity relative to both wild-type and engineered alternatives between 30 and 50  C and a range of pH levels. We demonstrate that untreated, postconsumer-PET from 51 different thermoformed products can all be almost completely degraded by FAST-PETase in 1 week. FAST-PETase can also depolymerize untreated, amorphous portions of a commercial water bottle and an entire thermally pretreated water bottle at 50 ºC. Finally, we demonstrate a closed-loop PET recycling process by using FAST-PETase and resynthesizing PET from the recovered monomers. Collectively, our results demonstrate a viable route for enzymatic plastic recycling at the industrial scale.

Computer-designed repurposing of chemical wastes into drugs

计算设计方案将化学废料变为药物

作者：Agnieszka Wołos, Dominik Koszelewski, Rafał Roszak, Sara Szymkuć et al.

链接：

摘要：

化学工业持续产生大量的化学废物，因此，设计“循环化学”方案以有效地将废料转化为有价值的产品是必要的。在这里，我们展示具有广泛合成知识的计算机如何帮助解决这一挑战。

使用正向合成Allchemy平台，我们从大约200种商业规模的回收废弃化学品中产生巨大的合成网络，从这些网络中回收数以万计的途径，可以产生约300种重要的药物和农药，然后根据可持续化学的公认指标，用算法对这些合成物进行排名。

通过实验，我们验证了其中几种途径，包括在“按需制药”流动化学平台上的工业现实展示。广泛采用这一废物利用的算法，可以加快化学品的生产性再利用，以避免废物产生的存储或抛弃成本，甚至可能造成的环境危害。

Abstract：

As the chemical industry continues to produce considerable quantities of waste chemicals, it is essential to devise ‘circular chemistry’ schemes to productively back-convert at least a portion of these unwanted materials into useful products. Here we show how computers equipped with broad synthetic knowledge can help address this challenge. Using the forward-synthesis Allchemy platform, we generate giant synthetic networks emanating from approximately 200 waste chemicals recycled on commercial scales, retrieve from these networks tens of thousands of routes leading to approximately 300 important drugs and agrochemicals, and algorithmically rank these syntheses according to the accepted metrics of sustainable chemistry. Several of these routes we validate by experiment, including an industrially realistic demonstration on a ‘pharmacy on demand’ flow-chemistry platform. Wide adoption of computerized waste-to-valuable algorithms can accelerate productive reuse of chemicals that would otherwise incur storage or disposal costs, or even pose environmental hazards.

Catalytic synthesis of phenols with nitrous oxide

一氧化二氮催化合成酚类化合物

作者：Franck Le Vaillant, Ana Mateos Calbet, Silvia González-Pelayo, Edward J. Reijerse, Shengyang Ni, Julia Busch & Josep Cornella

链接：

摘要：

在这里，我们报道了在温和的条件下（室温， bar N2O）将N2O插入到Ni-C键中，从而释放有价值的酚和良性N2。这一完全不同的有机金属C-O成键步骤不同于目前基于还原消除反映的方法，并使芳卤代烃转化为酚的替代催化方法成为可能。

该过程通过联吡啶基的配体使镍中心具有催化作用。该方法具有稳定性、温和性和高度选择性，能够适应碱基敏感功能，并允许从密集功能化的芳卤化物合成苯酚。

虽然该方法没有提供缓解一氧化二氮排放的解决方案，但它为丰富的一氧化二氮作为氧源的温和重新估值提供了蓝图。

Abstract：

Here we report an insertion of N2O into a Ni‒C bond under mild conditions (room temperature, –2 bar N2O), thus delivering valuable phenols and releasing benign N2. This fundamentally distinct organometallic C‒O bond-forming step differs from the current strategies based on reductive elimination and enables an alternative catalytic approach for the conversion of aryl halides to phenols. The process was rendered catalytic by means of a bipyridine-based ligands for the Ni centre. The method is robust, mild and highly selective, able to accommodate base-sensitive functionalities as well as permitting phenol synthesis from densely functionalized aryl halides. Although this protocol does not provide a solution to the mitigation of N2O emissions, it represents a reactivity blueprint for the mild revalorization of abundant N2O as an O source.