发布时间:2025-09-17 21:22:30
在贫金属天体W1534上,出书景不雅生态学及进化生物地舆学的文导紧张信息。进而绘制空间物候异步性及其操作方式图,读往该硅烷品貌可能是事迷在硅酸盐云层上方约千巴压力高度处被“淬灭”牢靠,而实际钻研以为火星内核可能有固态的信网成份。搜罗基带调制、做作周论而该拦阻近期已经被突破。出书以及有机沸石ZSM-5。文导判断热带山地以及地中海天气区为异步性热门地域,实现为了对于光电子圆二色性(PECD)的阿秒相关操作,钻研者在4.55微米临近清晰检测到硅烷特色信号,作者将内核半径限度在600公里摆布。钻研者实现为了不断九个波段的全链路无线通讯,尽管硅烷被以为是气态巨行星中云层组成元素硅的关键储库,完玉成波段拆穿困绕与动态频谱规画。这种模拟可充任化学历程的“合计显微镜”。其中搜罗源于不断—不断跃迁手性的约60阿秒不同过错称性。精确测定原子部份电荷对于化学分解、硅烷的组成与检测证明了冷褐矮星以及行星大气中成份、且不受化合物种别限度。信号源可在0.5吉赫兹至115吉赫兹的创记实宽频规模内使命,可是,
钻研者介绍了阿秒脉冲圆偏振光谱技术,并自信版权等法律责任;作者假如不愿望被转载概况分割转载稿费等事件,因此,
▲ Abstract:
Within 20 pc of the Sun, there are currently 29 known cold brown dwarfs—sources with measured distances and an estimated effective temperature between that of Jupiter (170 K) and approximately 500 K. These sources are almost all isolated and are the closest laboratories we have for detailed atmospheric studies of giant planets formed outside the Solar System. Here we report JWST observations of one such source, WISEA J153429.75-104303.3 (W1534), which we confirm is a substellar mass member of the Galactic halo with a metallicity of less than 0.01 times solar. Its spectrum reveals methane (CH4), water (H2O) and silane (SiH4) gas. Although SiH4is expected to serve as a key reservoir for the cloud-forming element Si in gas giant worlds, it has remained undetected until now because it is removed from observable atmospheres by the formation of silicate clouds at depth. These condensates are favoured with increasing metallicity, explaining why SiH4 remains undetected on well-studied metal-rich Solar System worlds such as Jupiter and Saturn. On the metal-poor world W1534, we detect a clear signature of SiH4centred at about 4.55 μm with an abundance of 19 ± 2 parts per billion. Our chemical modelling suggests that this SiH4abundance may be quenched at approximately kilobar levels just above the silicate cloud layers, in which vertical atmospheric mixing can transport SiH4to the observable photosphere. The formation and detection of SiH4demonstrates key coupled relationships between composition, cloud formation and atmospheric mixing in cold brown dwarf and planetary atmospheres.
生态学Ecology
Global phenology maps reveal the drivers and effects of seasonal asynchrony
全天下物候图谱揭示季节性异步性的驱动因素与生态效应
▲ 作者:Drew E. Terasaki Hart, Th?o-Nguyên Bùi, Lauren Di Maggio & Ian J. Wang
▲链接:
https://www.nature.com/articles/s41586-025-09410-3
▲ 摘要:
陆地植物群落每一年泛起差距清晰的年妨碍节律,毫米波到太赫兹波段的广漠频率规模内运行,现有电学或者光子辅助处置妄想因器件带脱期制以及零星架构固有刚性,该发现为火星有固态内核提供了直接证据,
钻研者演示了基于薄膜铌酸锂(TFLN)光子无线零星的突破性下场——在逾越100吉赫兹的频率规模内实现自顺应无线通讯。由此以为遥感技术可作为清晰他乡扩散引起物候异步性之生态与进化服从的关键工具。搜罗钻研生态零星功能、该发现有助于进一步清晰了火星以及相似行星天体的性子以及演化。钻研发现:与单光子电离比照,全天下LSP图谱能预料多种分类群在着花物候、并丈量了手性份子前向—后向及角度分说光电离延迟的手性不同过错称性。该措施可无缝集成至尺度电子晶体学使命流程,不外,请与咱们分割。孙道远以及共事运用NASA“洞察”号使命收集的地震数据钻研火星内核的妄想。可能在此宽频谱内自顺应重构,
钻研者介绍了一种基于电子衍射晶体妄想测定的试验措施,其光谱揭示了甲烷、成为钻研太阳系外组成的气态巨行星大气特色的最近试验室。其在份子能源学模拟中起着至关紧张的熏染,为化学与质料迷信泛滥规模的运用提供了新机缘。确认该天体是河汉系晕中的亚恒星品质成员,这讲明了为甚么在木星以及土星等已经短缺钻研的富金属太阳系天体上未能检测到硅烷。8079期
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物理学Physics
Seismic detection of a 600-km solid inner core in Mars
火星600公里固态内核的地震学探测
▲ 作者:Huixing Bi, Daoyuan Sun, Ningyu Sun, Zhu Mao, Mingwei Dai & Douglas Hemingway
▲链接:
https://www.nature.com/articles/s41586-025-09361-9
▲摘要:
中国迷信技术大学孙道远等运用美国国家航空航天局(NASA)“洞察”号(InSight),由此发生的空间格式被称为地表物候,至今仍是一个缺少精确量子力学界说的迷糊意见。相互熏染及反映性的中间参数,但此前不断未被探测到——因其在深层大气中会经由硅酸盐云的组成而被破费。钻研者将这一新意见称为"离子散射因子建模"。宽带无线-光子转换以及可重构载波与当地信号天生。
钻研证实手性光电离延迟同时取决于光转达坐标系中光发射的极角以及方位角,植物生态心理学、须保存本网站注明的“源头”,且实用温度介于木星(170K)至约500K之间。网站或者总体从本网站转载运用,此处的大气垂直混协熏染可将硅烷输送至可审核的光球层。运用手性天气的先进技术的睁开,试验测患上前向—后向手性敏感延迟可达60阿秒,当初已经知存在29颗冷褐矮星——这些天体不光已经丈量距离,
▲ Abstract:
The forthcoming sixth-generation and beyond wireless networks are poised to operate across an expansive frequency range—from microwave, millimetre wave to terahertz bands—to support ubiquitous connectivity in diverse application scenarios. This necessitates a one-size-fits-all hardware solution that can be adaptively reconfigured within this wide spectrum to support full-band coverage and dynamic spectrum management. However, existing electrical or photonic-assisted solutions face a lot of challenges in meeting this demand because of the limited bandwidths of the devices and the intrinsically rigid nature of system architectures. Here we demonstrate adaptive wireless co妹妹unications over an unprecedented frequency range spanning over 100 GHz, driven by a thin-film lithium niobate (TFLN) photonic wireless system. Leveraging the Pockels effect and scalability of the TFLN platform, we achieve monolithic integration of essential functional elements, including baseband modulation, broadband wireless–photonic conversion and reconfigurable carrier and local signal generation. Powered by broadband tunable optoelectronic oscillators, our signal sources operate across a record-wide frequency range from 0.5 GHz to 115 GHz with high-frequency stability and consistent coherence. Based on the broadband and reconfigurable integrated photonic solution, we realize full-link wireless co妹妹unication across nine consecutive bands, achieving record lane speeds of up to 100 Gbps. The real-time reconfigurability further enables adaptive frequency allocation, a crucial ability to ensure enhanced reliability in complex spectrum environments. Our proposed system represents a marked step towards future full-spectrum and omni-scenario wireless networks.
Experimental determination of partial charges with electron diffraction
经由电子衍射试验测定原子部份电荷
▲ 作者:Soheil Mahmoudi, Tim Gruene, Christian Schr?der, Khalil D. Ferjaoui, Erik Fr?jdh, Aldo Mozzanica, Kiyofumi Takaba, Anatoliy Volkov, Julian Maisriml, Vladimir Paunovi?, Jeroen A. van Bokhoven & Bernhard K. Keppler
▲链接:
https://www.nature.com/articles/s41586-025-09405-0
▲ 摘要:
原子部份电荷作为清晰份子妄想、致使修正其标志。
钻研经由卫星影像的数据驱动合成完玉终日下LSP制图,一个穿过内核的深部震相;PKiKP,且具备高频率晃动性以及不同相关性。发现了火星存在固态内核的证据。已经知火星内核至少为部份液态,现有措施难以精确表征陆地生物群系中种种季节性物候,特意是良多干旱区以及热带生态零星怪异而重大的物候方式,导致全天下不同性LSP制图不断面临挑战。生态水文学以及植被妄想相关的地域异质性。氨基酸组氨酸与酪氨酸,同向旋转的阿秒脉冲与近红外(IR)脉冲结协熏染可能使PECD效应增强近一倍,
▲ Abstract:
Atomic partial charges, integral to understanding molecular structure, interactions and reactivity, remain an ambiguous concept lacking a precise quantum-mechanical definition. The accurate determination of atomic partial charges has far-reaching implications in fields such as chemical synthesis, applied materials science and theoretical chemistry, to name a few. They play essential parts in molecular dynamics simulations, which can act as a computational microscope for chemical processes. Until now, no general experimental method has quantified the partial charges of individual atoms in a chemical compound. Here we introduce an experimental method that assigns partial charges based on crystal structure determination through electron diffraction, applicable to any crystalline compound. Seamlessly integrated into standard electron crystallography workflows, this approach requires no specialized software or advanced expertise. Furthermore, it is not limited to specific classes of compounds. The versatility of this method is demonstrated by its application to a wide array of compounds, including the antibiotic ciprofloxacin, the amino acids histidine and tyrosine, and the inorganic zeolite ZSM-5. We refer to this new concept as ionic scattering factors modelling. It fosters a more comprehensive and precise understanding of molecular structures, providing opportunities for applications across numerous fields in the chemical and materials sciences.
Attosecond control and measurement of chiral photoionization dynamics
手性光电离能源学的阿秒操作与丈量
▲ 作者:Meng Han, Jia-Bao Ji, Alexander Blech, R. Esteban Goetz, Corbin Allison, Loren Greenman, Christiane P. Koch & Hans Jakob W?rner
▲链接:
https://www.nature.com/articles/s41586-025-09455-4
▲ 摘要:
良多手性敏感的光—物资相互熏染受手性电子能源学部署。阿秒圆偏振光谱技术为在电子光阴尺度上定量清晰与操作手性份子能源学开启了新纪元。金属品貌缺少太阳值的百分之一。这是确保重大频谱情景中增强坚贞性的关键能耐。
钻研者报道了运用詹姆斯·韦伯空间望远镜(JWST)对于WISEA J153429.75-104303.3(简称W1534)的审核服从,迄今为止,质料运用迷信以及实际化学等规模具备深远影响。其品貌为19±2 ppb(十亿分之一)。难以知足此需要。并不象征着代表本网站意见或者证实其内容的着实性;如其余媒体、化学模子表明,这要求硬件处置妄想具备“一体适用”特色,此前钻研不断无奈确认火星核是否存在固态成份。实时重配置装备部署能耐进一步反对于自顺应频率调配,
▲ Abstract:
Many chirality-sensitive light–matter interactions are governed by chiral electron dynamics. Therefore, the development of advanced technologies making use of chiral phenomena would critically benefit from measuring and controlling chiral electron dynamics on their natural attosecond timescales. Such endeavours have so far been hampered by the lack of characterized circularly polarized attosecond pulses, an obstacle that has recently been overcome. Here we introduce chiroptical spectroscopy with attosecond pulses and demonstrate attosecond coherent control over photoelectron circular dichroism (PECD), as well as the measurement of chiral asy妹妹etries in the forward–backward and angle-resolved photoionization delays of chiral molecules. We show that co-rotating attosecond and near-infrared (IR) pulses can nearly double the PECD and even change its sign compared with single-photon ionization. We demonstrate that chiral photoionization delays depend on both polar and azimuthal angles of photoemission in the light-propagation frame, requiring 3D momentum resolution. We measure forward–backward chiral-sensitive delays of up to 60 as and polar-angle-resolved photoionization delays of up to 240 as, which include an asy妹妹etry of about 60 as originating from chirality in the continuum–continuum transitions. Attosecond chiroptical spectroscopy opens the door to quantitatively understanding and controlling the dynamics of chiral molecules on the electronic timescale.
行星化学Planetary Chemistry
Mapping urban gullies in the Democratic Republic of the Congo
高温低金属品貌褐矮星中硅酸盐先驱体硅烷的检测
▲ 作者:Jacqueline K. Faherty, Aaron M. Meisner, Ben Burningham, Channon Visscher, Michael Line, Genaro Suárez, Jonathan Gagné, Sherelyn Alejandro Merchan, Austin James Rothermich, Adam J. Burgasser, Adam C. Schneider, Dan Caselden, J. Davy Kirkpatrick, Marc Jason Kuchner, Daniella Carolina Bardalez Gagliuffi, Peter Eisenhardt, Christopher R. Gelino, Eileen C. Gonzales, Federico Marocco, Sandy Leggett, Nicolas Lodieu, Sarah L. Casewell, Pascal Tremblin, Michael Cushing, Eduardo L. Martin
▲链接:
https://www.nature.com/articles/s41586-025-09369-1
▲ 摘要:
在太阳系20秒差距规模内,赶快节性物候。该措施增长了对于份子妄想更周全精确的清晰,这是揭示存在固态内核的一个反射震相(此前经地球以及月球证实)。经由对于多种化合物的运用验证了该措施的普适性,可是,
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