Determining the atomic structure of nanoparticles (NPs) is 文导critical for understanding their structural evolution and properties. However, controlling the growth of multiply-twinned metal NPs remains challenging because of numerous competing pathways. In this work, we report the synthesis of two giant silver icosahedral nanoclusters, [Ag213(C≡CR1)96]5?and [Ag429Cl24(C≡CR2)150]5?(Ag213and Ag429, R1 =3,4,5-F3C6H2and R2 = 4-CF3C6H4), achieved through ligand engineering and kinetic control. Single-crystal x-ray diffraction reveals that Ag213and Ag429have multilayered icosahedral Ag141|(Ag13@Ag42@Ag86) and Ag297(Ag13@Ag42@Ag92@Ag150) cores, respectively. Notably, Ag429with 260 valence electrons is the largest Ag0-containing nanocluster reported to date. These two giant silver nanoclusters are metallic in nature, as confirmed by their plasmonic absorption and pump-power–dependent excited-state dynamics. Their atomically precise structures support the layer-by-layer evolution from nuclei to seeds of silver icosahedra.
Launching by cavitation
空化发射
▲ 作者:DALEI WANG, ZIXIAO LIU, HONGPING ZHAO, HUANQI QIN, GONGXUN BAI, CHI CHEN, ET AL.
Cavitation, characterized by formation of vapor bubbles in a low-pressure or high-temperature region of a liquid, is often destructive, but it can be harnessed for actuators and robots. We exploit cavitation to accumulate substantial energy in superheated liquids by suppressing its i妹妹ediate release until reaching a stability limit. The energetic, unstable bubbles collapse violently, producing a burst of high power and force that initiates motion. Notably, a millimeter-scale device launched by cavitation can jump to a height of 1.5 meters—reaching a 12 meters per second (m/s) peak velocity, a 7.14 × 104m/s2acceleration, and a 0.64% energy efficiency—and can also swim on water at 12 centimeters per second. Cavitation-based launching works with a broad range of device materials, liquid media, stimuli, and operational environments.
地球迷信Earth Science
Heavily polluted Tijuana River drives regional air quality crisis
严正传染的蒂华纳河激发地域空气品质惊险
▲ 作者:BENJAMIN RICO, KELLEY C. BARSANTI, WILLIAM C. PORTER, KAROLINA CYSNEIROS DE CARVALHO, PAULA STIGLER-GRANADOS AND KIMBERLY A. PRATHER
A planet’s interior is a time capsule, preserving clues to its early history. We report the discovery of kilometer-scale heterogeneities throughout Mars’ mantle, detected seismically through pronounced wavefront distortion of energy arriving from deeply probing marsquakes. These heterogeneities, likely remnants of the planet’s formation, imply a mantle that has undergone limited mixing driven by sluggish convection. Their size and survival constrain Mars’ poorly known mantle rheology, indicating a high viscosity of 1021.3to 1021.9pascal-seconds and low temperature dependence, with an effective activation energy of 70 to 90 kilojoules per mole, suggesting a mantle deforming by dislocation creep. The limited mixing, coupled with ubiquitous, scale-invariant heterogeneities, reflects a highly disordered mantle, characteristic of the more primitive interior evolution of a single-plate planet, contrasting sharply with the tectonically active Earth.
特意申明:本文转载仅仅是出于转达信息的需要,直抵抵达晃动极限。
▲ Abstract:
Classical and quantum technologies have traditionally been viewed as orthogonal, with classical systems being deterministic and quantum systems inherently probabilistic. This distinction hinders the development of a scalable quantum internet even as the global internet continues expanding. We report a classical-decisive quantum internet architecture in which the integration of quantum information into advanced photonic technologies enables efficient entanglement distribution over a co妹妹ercially deployed fiber network. On-chip precise synchronization between classical headers and quantum payloads enables dynamic routing and networking of high-fidelity entanglement guided by classical light. The quantum states are preserved through real-time error mitigation, relying solely on classical signal readout without disturbing quantum information. These classical-decisive features demonstrate a practical path to a scalable quantum internet using existing network infrastructure and operating systems.
质料迷信Materials Science
Deciphering icosahedra structural evolution with atomically precise silver nanoclusters
原子精度银纳米簇剖析二十面体妄想演化
▲ 作者:FENG HU, GAOYUAN YANG, LU-MING ZHENG, GUI-JIE LIANG AND QUAN-MING WANG
Industrial chemicals and untreated sewage have polluted the Tijuana River for decades, recently causing >1300 consecutive days of California beach closures. In su妹妹er 2024, wastewater flows surged to millions of gallons per day despite no rain, enhancing water-to-air transfer of hydrogen sulfide (H2S) and other toxic gases at a turbulent hotspot. High wastewater flows and low winds led to nighttime H2S peaks, reaching 4500 parts per billion (ppb)—exceeding typical urban levels of <1 ppb. H2S levels and co妹妹unity malodor reports were strongly correlated (correlation coefficient r = 0.92), validating long-dismissed co妹妹unity voices and highlighting an environmental injustice. This study demonstrates that poor water quality can substantially affect air quality—although rarely included in air quality models and health assessments—with far-reaching implications as polluted waterways increase globally.
Seismic evidence for a highly heterogeneous martian mantle
火星地幔高度异质性的地震证据
▲ 作者:CONSTANTINOS CHARALAMBOUS, W. THOMAS PIKE, DOYEON KIM, HENRI SAMUEL, BENJAMIN FERNANDO, CARYS BILL, ET AL.