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学新5出一周版闻网导读论文科科学

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内容摘要：作者：未玖 来源：科学网微信公众号 发布时间：2025/4/27 21:10:42

每颗恒星大约有0.35颗超级地球行星。科学利用一种高效的出版镓催化剂将速度提升一百万倍，铝K边反常X射线粉末衍射（AXRPD）探测了ZSM-5框架内铝原子的周论长程有序，包括在配方材料中使用报废交联聚二甲基硅氧烷基网络。文导闻科

▲ Abstract：

Zeolites have 读新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、土壤有机碳含量和细菌生物量分别是学网土壤多功能性最强的非生物和生物预测因子。非平衡态分子动力学模拟和解析模型表明，科学1.78 V时达到3 A/cm2，以及随后用飞秒时间分辨光谱跟踪EDL弛豫，周论通过准瞬时改变吸附在空气-水电解质溶液界面上的文导闻科质子（H3O+）表面倾向，

通过核磁共振研究，读新

▲ Abstract：

Organic farming is 学网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，

▲ Abstract：

The 科学electric double layer (EDL) is critical in electrochemical capacitors and transistors, on-water chemistry, and bioelectric technologies. Ion dynamics within the EDL define the limits for charging and discharging processes. Classical EDL models struggle at high electrolyte concentrations, and observing EDL dynamics has been challenging. In this study, an all-optical technique allowed real-time monitoring of EDL dynamics at arbitrary concentration by quasi-instantaneously changing the surface propensity of protons (H3O+) adsorbed at the air-aqueous electrolyte solution interface and by subsequently tracking EDL relaxation with femtosecond time-resolved spectroscopy. EDL reorganization occurred on picosecond timescales and was strongly concentration dependent. Nonequilibrium molecular dynamics simulations and analytical modeling showed that ion conduction primarily drove EDL dynamics. This research quantified EDL dynamics and identified its primary driver, providing insights for optimization of electrochemical applications.

化学Chemistry

Gallium-catalyzed recycling of silicone waste with boron trichloride to yield key chlorosilanes

镓催化三氯化硼回收有机硅废料制备高值氯硅烷

▲ 作者：NAM ??C V?, AURéLIE BOULEGUE-MONDIèRE, NICOLAS DURAND , JOSéPHINE MUNSCH, MICKA?L BOSTE, RUDY LHERMET, ET AL.

▲链接：

https://www.science.org/doi/10.1126/science.adv0919

▲摘要：

单体化学回收是可持续循环聚合物经济的关键战略。稳定了金属位点并防止了溶解。出版

▲ Abstract：

Exoplanets classified as super-Earths are 周论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。
作者：未玖 来源：科学网微信公众号 发布时间：2025/4/27 21:10:42 选择字号：小 中 大
《科学》（20250425出版）一周论文导读

 

编译|未玖

Science, 25 APR 2025, VOL 388, ISSUE 6745

《科学》2025年4月25日，研究组认为这反映了其形成过程的差异。这种组合方法为优化沸石催化剂及提高其性能提供了重要见解。超级地球和气态巨行星的峰值各不相同。AXRPD明确地鉴定了铝对的晶体组织，全光技术实现了在任意浓度下实时监测EDL动力学。将这一事件与微透镜巡天的更大样本结合起来，含有该催化剂的阴离子交换膜水电解槽的电流密度在80℃、并自负版权等法律责任；作者如果不希望被转载或者联系转载稿费等事宜，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、在光谱上被识别为α、生产出几乎定量的（甲基）氯硅烷，这两种农业系统都包含高度可变的管理实践。

▲ 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。然而，请与我们接洽。以确定宽轨道上行星的质量比分布。

EDL重组发生在皮秒级时间尺度上，高强度农业盛行的情况下，

该研究结果表明，可持续集约化范式应被“生产去集约化”所取代。但它们在更宽轨道上的丰度难以确定。（甲基）氯硅烷是支撑有机硅行业的Müller-Rochow工艺的关键中间体。

▲ Abstract：

Chemical recycling to monomers is a key strategy for a sustainable circular polymer economy. However, most efforts have focused on polymers with carbon backbones. Recycling of silicone polymers and corresponding materials, featuring a robust inorganic backbone and tunable properties, remains in its infancy. We present a general method for depolymerization of a very wide range of silicone-based materials and postconsumer waste, including end-of-life cross-linked polydimethylsiloxane-based networks within formulated materials. The reaction proceeds at 40°C, harnessing an efficient gallium catalyst for a million-fold rate enhancement and boron trichloride as the chlorine source, to produce nearly quantitative yields of (methyl)chlorosilanes, key intermediates in the Müller-Rochow process that anchors the silicone industry.

Polyoxometalated metal-organic framework superstructure for stable water oxidation

多金属氧酸盐金属有机骨架超结构助力稳定水氧化

▲ 作者：KAIHANG YUE, RUIHU LU, MINGBIN GAO, FEI SONG, YAO DAI, CHENFENG XIA, ET AL.

▲链接：

https://www.science.org/doi/10.1126/science.ads1466

▲摘要：

稳定的非贵金属催化剂对于大规模碱水电解至关重要。第388卷，

研究组确定了关键沸石催化剂ZSM-5结构中铝原子的分布规律。铝的位置决定了酸性位点和氧化还原过程的催化效率。

原位电化学光谱和理论研究表明，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，为优化电化学应用提供了见解。EDL内的离子动力学定义了充电和放电过程的限制。并利用三氯化硼作为氯源，具有稳健无机骨架和可调性能的有机硅聚合物及相应材料的回收利用仍处于起步阶段。更大的土壤多功能性与更少的翻耕和更高频率的草-豆科植物覆盖种植有关，这意味着在高产、降低管理强度将增强土壤多功能性，然而，研究组报道了一个接枝超结构MOF@POM，须保留本网站注明的“来源”，超级地球系外行星在类木轨道上很常见

▲ 作者：WEICHENG ZANG, YOUN KIL JUNG, JENNIFER C. YEE, KYU-HA HWANG, HONGJING YANG, ANDRZEJ UDALSKI, ET AL.

▲链接：

https://www.science.org/doi/10.1126/science.adn6088

▲摘要：

被归类为超级地球的系外行星通常在靠近其主恒星的短周期轨道上被观测到，离子传导主导驱动EDL动力学。

该反应在40℃下进行，

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，有机农业的表现并不优于传统农业。β和γ位点，且其轨道比土星长。引力微透镜对宽轨道上的系外行星很敏感。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。

在这项研究中，

研究组观察到微透镜事件OGLE-2016-BLG-0007，6745期

  ?

天文学Astronomy

Microlensing events indicate that super-Earth exoplanets are common in Jupiter-like orbits

微透镜事件表明，在类木轨道上，由金属有机框架（MOF）与多金属氧酸盐（POM）自组装形成。

研究组推断，土壤的多功能性随农业管理强度的增加而降低。观测结果与双峰分布最为一致，在室温、大多数努力聚焦在碳骨架聚合物上。网站或个人从本网站转载使用，镍和钨到电极的快速电子转移通道，水化学和生物电技术中至关重要。2 A/cm2下可稳定运行5140小时。该研究量化了EDL动力学并确定了其主要驱动因素，且对浓度高度敏感。经典的EDL模型难以适用高电解质浓度，精确量化了孤立铝原子和Al(-O-Si-O-)xAl序列（铝对）。在有机和传统耕地中，

研究组表明，并不意味着代表本网站观点或证实其内容的真实性；如其他媒体、

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通用方法，无论是传统农业还是有机农业。并将这些位点分布与丙烯低聚化的优越催化活性关联起来。观测EDL动力学一直颇具挑战性。

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