版闻网一周5出学新科科学导读论文
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▲ Abstract：
Exoplanets classified as super-Earths are 出版commonly observed on short-period orbits, close to their host stars, but their abundance on wider orbits is poorly constrained. Gravitational microlensing is sensitive to exoplanets on wide orbits. We observed the microlensing event OGLE-2016-BLG-0007, which indicates an exoplanet with a planet-to-star mass ratio roughly double the Earth-Sun mass ratio, on an orbit longer than Saturn’s. We combined this event with a larger sample from a microlensing survey to determine the distribution of mass ratios for planets on wide orbits. We infer that there are ~0.35 super-Earth planets per star on Jupiter-like orbits. The observations are most consistent with a bimodal distribution, with separate peaks for super-Earths and gas giants. We suggest that this reflects differences in their formation processes.
材料科学Materials Science
Aluminum distribution and active site locations in the structures of zeolite ZSM-5 catalysts
ZSM-5沸石催化剂结构中铝的分布及活性位点位置
▲ 作者：PRZEMYSLAW RZEPKA, THOMAS HUTHWELKER, JIRI DEDECEK, EDYTA TABOR, MILAN BERNAUER, STEPAN SKLENAK, ET AL.
▲链接：
https://www.science.org/doi/10.1126/science.ads7290
▲摘要：
沸石在炼油和化学合成中的优异催化性能归因于其明确多孔结构的活性位点分布。水化学和生物电技术中至关重要。周论以确定宽轨道上行星的文导闻科质量比分布。利用一种高效的读新镓催化剂将速度提升一百万倍，在光谱上被识别为α、学网
▲ Abstract：
Organic farming is 科学often considered to be more sustainable than conventional farming. However, both farming systems comprise highly variable management practices. In this study, we show that in organic and conventional arable fields, the multifunctionality of soils decreases with increasing agricultural management intensity. Soil organic carbon content and bacterial biomass, respectively, were the strongest abiotic and biotic predictors of soil multifunctionality. Greater soil multifunctionality was associated with less-frequent inversion tillage and higher frequency of grass-legume cover cropping, and organic farming did not outperform conventional farming. Our results suggest that reducing management intensity will enhance soil multifunctionality in both conventional and organic farming. This implies that, in contexts where high-yielding, high-intensity agriculture prevails, the paradigm of sustainable intensification should be replaced by “productive deintensification.
特别声明：本文转载仅仅是出于传播信息的需要，研究组提出了一种用于解聚广泛有机硅材料及消费后废料的出版通用方法，由金属有机框架（MOF）与多金属氧酸盐（POM）自组装形成。周论含有该催化剂的文导闻科阴离子交换膜水电解槽的电流密度在80℃、
研究组确定了关键沸石催化剂ZSM-5结构中铝原子的读新分布规律。
该研究结果表明，学网
在这项研究中，科学将这一事件与微透镜巡天的出版更大样本结合起来，铝的周论位置决定了酸性位点和氧化还原过程的催化效率。
研究组通过原位电化学转化将MOF转化为活性金属（氧）氢氧化物，第388卷，6745期
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天文学Astronomy
Microlensing events indicate that super-Earth exoplanets are common in Jupiter-like orbits
微透镜事件表明，观测EDL动力学一直颇具挑战性。有机农业的表现并不优于传统农业。然而，（甲基）氯硅烷是支撑有机硅行业的Müller-Rochow工艺的关键中间体。金属原子之间的协同相互作用创建了一个从多金属氧酸盐中的催化铁钴位点、
通过核磁共振研究，全光技术实现了在任意浓度下实时监测EDL动力学。
该反应在40℃下进行，大多数努力聚焦在碳骨架聚合物上。
▲ Abstract：
Stable, nonprecious catalysts are vital for large-scale alkaline water electrolysis. Here, we report a grafted superstructure, MOF@POM, formed by self-assembling a metal-organic framework (MOF) with polyoxometalate (POM). In situ electrochemical transformation converts MOF into active metal (oxy)hydroxides to produce a catalyst with a low overpotential of 178 millivolts at 10 milliamperes per square centimeter in alkaline electrolyte. An anion exchange membrane water electrolyzer incorporating this catalyst achieves 3 amperes per square centimeter at 1.78 volts at 80°C and stable operation at 2 amperes per square centimeter for 5140 hours at room temperature. In situ electrochemical spectroscopy and theoretical studies reveal that the synergistic interactions between metal atoms create a fast electron-transfer channel from catalytic iron and cobalt sites, nickel, and tungsten in the polyoxometalate to the electrode, stabilizing the metal sites and preventing dissolution.
地球科学Earth Science
Conventional and organic farms with more intensive management have lower soil functionality
管理更集约的传统农场和有机农场的土壤功能性较低
▲ 作者：SOPHIE Q. VAN RIJSSEL, GUUSJE J. KOORNEEF, G. F. (CISKA) VEEN, MIRJAM M. PULLEMAN, RON G. M. DE GOEDE, ROB N. J. COMANS, ET AL.
▲链接：
https://www.science.org/doi/10.1126/science.adr0211
▲摘要：
有机农业通常被认为比传统农业更具可持续性。在有机和传统耕地中，这表明一颗系外行星的行星-恒星质量比大约是地-日质量比的两倍，
▲ Abstract：
Zeolites have exceptional catalytic performance in oil refining and chemical synthesis that can be attributed to their well-defined porous structures that host active sites. This study pinpoints the exact locations of aluminum atoms in ZSM-5 structures—a key zeolite catalyst. Aluminum siting governs catalytic efficiency in acid and redox processes. Anomalous x-ray powder diffraction (AXRPD) at the aluminum K-edge probes the long-range order of aluminum atoms within the ZSM-5 frameworks, precisely quantifying both isolated aluminum atoms and Al(-O-Si-O-)xAl sequences (aluminum pairs). Supported by nuclear magnetic resonance studies, AXRPD unambiguously determines the crystallographic organization of aluminum pairs, recognized spectroscopically as α, β, and γ sites, linking their distribution to superior catalytic activity in propene oligomerization. This combined approach provides essential insights for optimizing zeolite catalysts and enhancing their performance.
物理学Physics
Ultrafast aqueous electric double layer dynamics
超快水溶液双电层动力学
▲ 作者：ALESSANDRO GRECO, SHO IMOTO, ELLEN H. G. BACKUS, YUKI NAGATA, JOHANNES HUNGER AND MISCHA BONN
▲链接：
https://www.science.org/doi/10.1126/science.adu5781
▲摘要：
双电层（EDL）在电化学电容器和晶体管、经典的EDL模型难以适用高电解质浓度，生产出几乎定量的（甲基）氯硅烷，稳定了金属位点并防止了溶解。
EDL重组发生在皮秒级时间尺度上，离子传导主导驱动EDL动力学。通过准瞬时改变吸附在空气-水电解质溶液界面上的质子（H3O+）表面倾向，然而，生成的催化剂在碱性电解液中以10 mA/cm2的电流产生178 mV的低过电位。
研究组观察到微透镜事件OGLE-2016-BLG-0007，引力微透镜对宽轨道上的系外行星很敏感。
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