极品白丝美女被日-极品超嫩在线视频-极品成人-极品美女-极品女神-极品欧美一区二区-极品人妖-极品盛宴在线视频-极品视频在线观看-极品小鸟伊人

?

Science,科学 25 APR 2025, VOL 388, ISSUE 6745

《科学》2025年4月25日，第388卷，出版6745期

???周論%E3%80%90WhatsApp%20+86%2015855158769%E3%80%91kettlebell%20basic%20workout

天文学Astronomy

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

微透镜事件表明，超级地球系外行星在类木轨道上很常见

▲ 作者：WEICHENG ZANG,文导闻科 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，但它们在更宽轨道上的读新丰度难以确定。引力微透镜对宽轨道上的学网系外行星很敏感。

研究组观察到微透镜事件OGLE-2016-BLG-0007，科学这表明一颗系外行星的出版行星-恒星质量比大约是地-日质量比的两倍，且其轨道比土星长。周论将这一事件与微透镜巡天的文导闻科%E3%80%90WhatsApp%20+86%2015855158769%E3%80%91kettlebell%20basic%20workout更大样本结合起来，以确定宽轨道上行星的读新质量比分布。

研究组推断，学网在类木轨道上，科学每颗恒星大约有0.35颗超级地球行星。出版观测结果与双峰分布最为一致，周论超级地球和气态巨行星的峰值各不相同。研究组认为这反映了其形成过程的差异。

▲ Abstract：

Exoplanets classified as super-Earths are 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。

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。铝K边反常X射线粉末衍射（AXRPD）探测了ZSM-5框架内铝原子的长程有序，精确量化了孤立铝原子和Al(-O-Si-O-)_xAl序列（铝对）。

通过核磁共振研究，AXRPD明确地鉴定了铝对的晶体组织，在光谱上被识别为α、β和γ位点，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。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。

▲ 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、水化学和生物电技术中至关重要。EDL内的离子动力学定义了充电和放电过程的限制。经典的EDL模型难以适用高电解质浓度，观测EDL动力学一直颇具挑战性。

在这项研究中，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，以及随后用飞秒时间分辨光谱跟踪EDL弛豫，全光技术实现了在任意浓度下实时监测EDL动力学。

EDL重组发生在皮秒级时间尺度上，且对浓度高度敏感。非平衡态分子动力学模拟和解析模型表明，离子传导主导驱动EDL动力学。该研究量化了EDL动力学并确定了其主要驱动因素，为优化电化学应用提供了见解。

▲ Abstract：

The 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。然而，大多数努力聚焦在碳骨架聚合物上。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。

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，包括在配方材料中使用报废交联聚二甲基硅氧烷基网络。

该反应在40℃下进行，利用一种高效的镓催化剂将速度提升一百万倍，并利用三氯化硼作为氯源，生产出几乎定量的（甲基）氯硅烷，（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。研究组报道了一个接枝超结构MOF@POM，由金属有机框架（MOF）与多金属氧酸盐（POM）自组装形成。

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，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。含有该催化剂的阴离子交换膜水电解槽的电流密度在80℃、1.78 V时达到3 A/cm²，在室温、2 A/cm²下可稳定运行5140小时。

原位电化学光谱和理论研究表明，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、镍和钨到电极的快速电子转移通道，稳定了金属位点并防止了溶解。

▲ 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，这两种农业系统都包含高度可变的管理实践。

研究组表明，在有机和传统耕地中，土壤的多功能性随农业管理强度的增加而降低。土壤有机碳含量和细菌生物量分别是土壤多功能性最强的非生物和生物预测因子。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，有机农业的表现并不优于传统农业。

该研究结果表明，降低管理强度将增强土壤多功能性，无论是传统农业还是有机农业。这意味着在高产、高强度农业盛行的情况下，可持续集约化范式应被“生产去集约化”所取代。

▲ Abstract：

Organic farming is 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.