編譯 | 李言

Science, 24 DEC, VOL 374, ISSUE 6575

《科學(xué)》2021年12月24日，第374卷，6575期

材料科學(xué)Materials Science

A stable aluminosilicate zeolite with intersecting three-dimensional extra-large pores

一種具有交叉三維超大孔隙得穩(wěn)定鋁硅酸鹽沸石

▲ ：QING-FANG LIN, ZIHAO REI GAO, CONG LIN et al.

▲ 鏈接：

特別science.org/doi/10.1126/science.abk3258

▲ 摘要

沸石是一種具有重要工業(yè)應(yīng)用得結(jié)晶多孔材料，例如在催化和吸附分離過程中使用。然而，進(jìn)入和離開吸附和反應(yīng)發(fā)生得內(nèi)部密閉空間受到其孔隙孔徑得限制。具有較大孔隙、能夠處理較大分子得穩(wěn)定多維沸石在精細(xì)化學(xué)工業(yè)和石油加工中是有需求得，而世界仍然依賴石油加工作為燃料。

目前已知得超大孔分子篩穩(wěn)定性差和缺乏孔隙多維度，限制了它得使用。我們報告了ZEO-1，一種具有交叉三維超大孔隙得堅固得鋁硅酸鹽沸石。ZEO-1在1000°C下依然保持穩(wěn)定，具有非凡得比表面積（1000平方米/克），并顯示出作為裂化催化劑得潛力。

▲ Abstract

Zeolites are crystalline porous materials with important industrial applications, including uses in catalytic and adsorption-separation processes. Access into and out of their inner confined space, where adsorption and reactions occur, is limited by their pore apertures. Stable multidimensional zeolites with larger pores able to process larger molecules are in demand in the fine chemical industry and for the oil processing on which the world still relies for fuels. Currently known extra-large-pore zeolites display poor stability and/or lack pore multidimensionality, limiting their usefulness. We report ZEO-1, a robust, fully connected aluminosilicate zeolite with mutually intersecting three-dimensional extra-large plus three-dimensional large pores. ZEO-1 is stable up to 1000°C, has an extraordinary specific surface area (1000 square meters per gram), and shows potential as a catalytic cracking catalyst.

Stabilized tilted-octahedra halide perovskites inhibit local formation of performance-limiting phases

穩(wěn)定得傾斜八面體鹵化物鈣鈦礦抑制局部性能限制相得形成

▲ ：TIARNAN A. S. DOHERTY, SATYAWAN NAGANE, DOMINIK J. KUBICKI et al.

▲ 鏈接：

特別science.org/doi/10.1126/science.abk1603

▲ 摘要

穩(wěn)定光活性甲酰胺(FA)基鹵化物鈣鈦礦用于鈣鈦礦光伏得影響集中在立方甲酰胺碘化鉛(α-FAPbI3)相得生長，通過經(jīng)驗合金與銫或甲基銨(MA)陽離子。結(jié)果表明，這種穩(wěn)定得富FA鈣鈦礦是非立方得，并且在室溫下表現(xiàn)出約2°得八面體傾斜。

這種傾斜只有使用局部納米結(jié)構(gòu)表征技術(shù)才能解決，通過阻止從光活性相變到六邊形相變得轉(zhuǎn)變，賦予了相位穩(wěn)定性。雖然體相似乎穩(wěn)定時，異質(zhì)陽離子分布允許微觀不穩(wěn)定區(qū)域得形成；我們發(fā)現(xiàn)這些轉(zhuǎn)變?yōu)榱呅味嘈停瑢?dǎo)致局域阱幫助性能損失和光不穩(wěn)定性。

利用表面結(jié)合得乙二胺四乙酸，我們設(shè)計了一個八面體傾斜得純α-FAPbI3薄膜，沒有任何陽離子合金化。模板化得光活性FAPbI3薄膜對熱、環(huán)境和光脅迫都非常穩(wěn)定。

▲ Abstract

Efforts to stabilize photoactive formamidinium (FA)–based halide perovskites for perovskite photovoltaics have focused on the growth of cubic formamidinium lead iodide (α-FAPbI3) phases by empirically alloying with cesium, methylammonium (MA) cations, or both. We show that such stabilized FA-rich perovskites are noncubic and exhibit ~2° octahedral tilting at room temperature. This tilting, resolvable only with the use of local nanostructure characterization techniques, imparts phase stability by frustrating transitions from photoactive to hexagonal phases. Although the bulk phase appears stable when examined macroscopically, heterogeneous cation distributions allow microscopically unstable regions to form; we found that these transitioned to hexagonal polytypes, leading to local trap-assisted performance losses and photoinstabilities. Using surface-bound ethylenediaminetetraacetic acid, we engineered an octahedral tilt into pure α-FAPbI3 thin films without any cation alloying. The templated photoactive FAPbI3 film was extremely stable against thermal, environmental, and light stressors.

Semiconductor nanochannels in metallic carbon nanotubes by thermomechanical chirality alteration

熱機械手性改變金屬碳納米管中得半導(dǎo)體納米通道

▲ ：DAI-MING TANG, SERGEY V. EROHIN, DMITRY G. KVASHNIN et al.

▲ 鏈接：

特別science.org/doi/10.1126/science.abi8884

▲ 摘要

碳納米管具有螺旋結(jié)構(gòu)，其中手性決定了它們是金屬還是半導(dǎo)體。利用原位透射電子顯微鏡，我們通過加熱和機械應(yīng)變改變單壁碳納米管得局部手性，從而控制單個單壁碳納米管得電子性質(zhì)。

我們觀察到向更大得手性角區(qū)域過渡得趨勢，并從位錯形成能得角度來解釋。利用金屬納米管源極和漏極之間得半導(dǎo)體通道共價鍵合，實現(xiàn)了可控得金屬-半導(dǎo)體過渡。此外，在溝道長度為2.8納米得納米管晶體管中，在室溫下表現(xiàn)出相干量子干涉。

▲ Abstract

Carbon nanotubes have a helical structure wherein the chirality determines whether they are metallic or semiconducting. Using in situ transmission electron microscopy, we applied heating and mechanical strain to alter the local chirality and thereby control the electronic properties of individual single-wall carbon nanotubes. A transition trend toward a larger chiral angle region was observed and explained in terms of orientation-dependent dislocation formation energy. A controlled metal-to-semiconductor transition was realized to create nanotube transistors with a semiconducting nanotube channel covalently bonded between a metallic nanotube source and drain. Additionally, quantum transport at room temperature was demonstrated for the fabricated nanotube transistors with a channel length as short as 2.8 nanometers.

物理學(xué)Physics

Terahertz light–driven coupling of antiferromagnetic spins to lattice

太赫茲光驅(qū)動得反鐵磁自旋與晶格得耦合

▲ ：EVGENY A. MASHKOVICH, KIRILL A. GRISHUNIN, ROMAN M. DUBROVIN et al.

▲ 鏈接：

特別science.org/doi/10.1126/science.abk1121

▲ 摘要

理解自旋晶格耦合是現(xiàn)代凝聚態(tài)物理得一個關(guān)鍵挑戰(zhàn)，對超快和二維磁具有至關(guān)重要得意義。自旋和晶格之間角動量和能量轉(zhuǎn)移得效率，對自旋電子學(xué)、磁學(xué)和磁數(shù)據(jù)存儲中控制自旋得能力施加了基本得速度限制。

我們報告了一種由太赫茲光脈沖驅(qū)動得自旋晶格耦合得有效非線性機制。一個近單周期得太赫茲脈沖與反鐵磁體二氟化鈷中得相干磁態(tài)共振相互作用，激發(fā)拉曼活動得太赫茲聲子。結(jié)果揭示了反鐵磁體得獨特功能，允許超快自旋晶格耦合使用光。

▲ Abstract

Understanding spin-lattice coupling represents a key challenge in modern condensed matter physics, with crucial importance and implications for ultrafast and two-dimensional magnetism. The efficiency of angular momentum and energy transfer between spins and the lattice imposes fundamental speed limits on the ability to control spins in spintronics, magnonics, and magnetic data storage. We report on an efficient nonlinear mechanism of spin-lattice coupling driven by terahertz light pulses. A nearly single-cycle terahertz pulse resonantly interacts with a coherent magnonic state in the antiferromagnet cobalt difluoride (CoF2) and excites the Raman-active terahertz phonon. The results reveal the distinctive functionality of antiferromagnets that allows ultrafast spin-lattice coupling using light.

人類進(jìn)化Human Evolution

The energetics of uniquely human subsistence strategies

人類特有得生存策略得能量學(xué)

▲ ：THOMAS S. KRAFT, VIVEK V. VENKATARAMAN, IAN J. WALLACEALYSSA N. CRITTENDEN et al.

▲ 鏈接：

特別science.org/doi/10.1126/science.abf0130

▲ 摘要

與其他類人猿相比，人類進(jìn)化而來得一系列特征，包括大腦變大、生育率提高、發(fā)育周期和壽命較長等，造成了異常高得能量消耗。人類得生存戰(zhàn)略如何適應(yīng)我們擴大得能源預(yù)算？我們發(fā)現(xiàn)，與其他類人猿相比，人類狩獵采集者和自給自足得農(nóng)民在生存上花費得精力更多，但時間更少，每小時獲得得能量明顯更多，并且達(dá)到了類似得能源效率。

這些發(fā)現(xiàn)修正了我們對人類能量進(jìn)化得理解，表明人類主要通過增加能量獲取率來提供更多得能量預(yù)算，而不是通過節(jié)能得適應(yīng)，如經(jīng)濟得兩足行走或復(fù)雜得工具使用，以降低生活成本和提高生活得能源效率。我們認(rèn)為，人類生存策略節(jié)省下來得時間為中心位置得社會互動和社會學(xué)習(xí)提供了更多得閑暇時間，這對累積得文化進(jìn)化至關(guān)重要。

▲ Abstract

The suite of derived human traits, including enlarged brains, elevated fertility rates, and long developmental periods and life spans, imposes extraordinarily high energetic costs relative to other great apes. How do human subsistence strategies accommodate our expanded energy budgets? We found that relative to other great apes, human hunter-gatherers and subsistence farmers spend more energy but less time on subsistence, acquire substantially more energy per hour, and achieve similar energy efficiencies. These findings revise our understanding of human energetic evolution by indicating that humans afford expanded energy budgets primarily by increasing rates of energy acquisition, not through energy-saving adaptations such as economical bipedalism or sophisticated tool use that decrease subsistence costs and improve the energetic efficiency of subsistence. We argue that the time saved by human subsistence strategies provides more leisure time for social interaction and social learning in central-place locations and would have been critical for cumulative cultural evolution.

古生物學(xué)Paleontology

Early giant reveals faster evolution of large body size in ichthyosaurs than in cetaceans

早期巨獸揭示魚龍比鯨類更快地進(jìn)化出更大體型

▲ ：P. MARTIN SANDER, EVA MARIA GRIEBELE, NICOLE KLEINJORGE VELEZ JUARBE et al.

▲ 鏈接：

特別science.org/doi/10.1126/science.abf5787

▲ 摘要

海洋羊膜動物得體型跨越了六個數(shù)量級，然而控制這種多樣性進(jìn)化得因素在很大程度上是未知得?，F(xiàn)代海洋初級產(chǎn)量得提高被認(rèn)為是鯨類巨獸出現(xiàn)得先決條件，但這種條件不能解釋三疊紀(jì)魚龍得巨獸現(xiàn)象。

我們展示來自美國內(nèi)華達(dá)州中三疊紀(jì)化石山動物區(qū)系得一種新得巨型魚龍Cymbospondylus youngorum sp. 11 .，它具有2米長得頭骨，強調(diào)了體型得快速進(jìn)化。令人驚訝得是，化石山動物群得組成在大小范圍上可以與現(xiàn)代海洋哺乳動物相媲美，能量通量模型表明，在魚龍誕生后不久，中三疊世得海洋食物網(wǎng)能夠支持幾種處于高營養(yǎng)水平得大型身體魚龍。

▲ Abstract

Body sizes of marine amniotes span six orders of magnitude, yet the factors that *erned the evolution of this diversity are largely unknown. High primary production of modern oceans is considered a prerequisite for the emergence of cetacean giants, but that condition cannot explain gigantism in Triassic ichthyosaurs. We describe the new giant ichthyosaur Cymbospondylus youngorum sp. nov. with a 2-meter-long skull from the Middle Triassic Fossil Hill Fauna of Nevada, USA, underscoring rapid size evolution despite the absence of many modern primary producers. Surprisingly, the Fossil Hill Fauna rivaled the composition of modern marine mammal faunas in terms of size range, and energy-flux models suggest that Middle Triassic marine food webs were able to support several large-bodied ichthyosaurs at high trophic levels, shortly after ichthyosaur origins.