編譯|李言
Science, 4 Sep 2025, VOL 389, ISSUE 6764
《科學(xué)》2025年9月4日,第389卷,6764期
材料科學(xué)Material Sciences
Rapid, low-temperature nanodiamond formation by electron-beam activation of adamantane C–H bonds
電子束激活金剛烷C–H鍵實現(xiàn)低溫快速合成納米金剛石
▲ 作者:Jiarui Fu, Takayuki Nakamuro, and Eiichi Nakamura
▲ 鏈接:
https://www.science.org/doi/10.1126/science.adw2025
▲ 摘要:
金剛石與金剛烷(Ad)雖具有相同的Td對稱性碳骨架結(jié)構(gòu),但將金剛烷轉(zhuǎn)化為金剛石一直面臨挑戰(zhàn)——該過程需實現(xiàn)碳?xì)洌––H)鍵的選擇性斷裂并將單體組裝成金剛石晶格。
我們的方法不同于傳統(tǒng)的高溫高壓金剛石合成技術(shù)。通過在真空環(huán)境中以80—200千電子伏特電子束在100—296開爾文溫度下輻照金剛烷亞微米晶體數(shù)十秒,我們成功制備出立方晶結(jié)構(gòu)的無缺陷納米金剛石(NDs),同時伴隨氫氣逸出。
時間分辨透射電子顯微鏡實時觀測到金剛烷寡聚體初步形成并最終轉(zhuǎn)變?yōu)榍蛐渭{米金剛石的過程。顯著的動力學(xué)同位素效應(yīng)表明C–H鍵斷裂是反應(yīng)速控步驟,且其他測試碳?xì)浠衔锞茨苄纬杉{米金剛石。
▲ Abstract:
Diamond and adamantane (Ad) share a Td-symmetric carbon skeleton, but converting Ad to diamond has been challenging because it requires selective carbon-hydrogen (C–H) bond cleavage and monomer assembly into a diamond lattice. Our approach differs from the conventional high-temperature, high-pressure diamond syntheses. We electron-irradiated Ad submicrocrystals at 80 to 200 kilo–electron volts and 100 to 296 kelvin in vacuum for tens of seconds. This process yielded defect-free nanodiamonds (NDs) of cubic crystal structure, accompanied by hydrogen gas evolution. Time-resolved transmission electron microscopy revealed the initial formation of Ad oligomers transforming into spherical NDs. A sizable kinetic isotope effect indicates that C–H cleavage was rate-determining, and other hydrocarbons tested failed to form NDs.
Order-to-disorder transition due to entropy in layered and 2D carbides
層狀與二維碳化物中熵驅(qū)動的有序—無序轉(zhuǎn)變
▲ 作者:Brian C. Wyatt, Yinan Yang et al.
▲ 鏈接:
https://www.science.org/doi/10.1126/science.adv4415
▲ 摘要:
在成分復(fù)雜的材料中,關(guān)于焓與熵對所謂'高熵材料'結(jié)構(gòu)和短程有序化影響的問題一直存在爭議。為解決這一爭議,我們合成并研究了40種含2—9種金屬的M4AlC3層狀碳化物相,發(fā)現(xiàn)當(dāng)熵增尚未達到足以實現(xiàn)過渡金屬原子面完全無序化之前,焓驅(qū)動的短程有序始終存在。
我們將所有這些層狀碳化物相轉(zhuǎn)化為二維片層結(jié)構(gòu),并揭示了有序與無序狀態(tài)對其表面特性和電子行為的調(diào)控作用。本研究證明了焓—熵競爭對多組分材料短程有序的關(guān)鍵影響。
▲ Abstract:
In compositionally complex materials, there is controversy on the effect of enthalpy versus entropy on the structure and short-range ordering in so-called high-entropy materials. To help address this controversy, we synthesized and probed 40 M4AlC3 layered carbide phases containing two to nine metals and found that short-range ordering from enthalpy was present until the entropy increased enough to achieve complete disordering of the transition metals in their atomic planes. We transformed all of these layered carbide phases into two-dimensional (2D) sheets and showed the effects of the order versus disorder on their surface properties and electronic behavior. This study suggests the key effect that the competition between enthalpy and entropy has on short-range order in multicompositional materials.
醫(yī)學(xué)Medicine
Estrogen-regulated renal progenitors determine pregnancy adaptation and preeclampsia
雌激素調(diào)控的腎臟祖細(xì)胞決定妊娠適應(yīng)性與子癇前發(fā)病機制
▲ 作者:Carolina Conte, Maria Lucia Angelotti et al.
▲ 鏈接:
https://www.science.org/doi/10.1126/science.adp4629
▲ 摘要:
▲ Abstract:
The global burden of kidney disease displays marked sexual dimorphism. Lineage tracing and single-cell RNA-sequencing revealed that starting from puberty, estrogen signaling in female mice supports self-renewal and differentiation of renal progenitors to increase filtration capacity, reducing sensitivity to glomerular injury compared with that of males. This phenomenon accelerated as female kidneys adapted to the workload of pregnancy. Deletion of estrogen receptor α in renal progenitors disrupted this adaptation, leading to preeclampsia, fetal growth restriction, and increased maternal risk of hypertension and chronic kidney disease. Offspring from affected mothers had fewer nephrons, resulting in early-life hypertension and greater susceptibility to kidney disease. These results highlight the fundamental role of kidney fitness and renal progenitors for pregnancy and preeclampsia and as a determinant of sexual dimorphism in kidney disease.
化學(xué)Chemsitry
Photochemical H2 dissociation for nearly quantitative CO2 reduction to ethylene
光化學(xué)氫解離實現(xiàn)近定量二氧化碳還原制備乙烯
▲ 作者:Ping Jin, Pu Guo et al.
▲ 鏈接:
https://www.science.org/doi/10.1126/science.adq3445
▲ 摘要:
通過二氧化碳加氫制備烯烴是催化領(lǐng)域長期追求的目標(biāo)。由于高溫下異裂氫解離這一關(guān)鍵步驟會導(dǎo)致選擇性控制復(fù)雜化,常規(guī)反應(yīng)通常生成多碳混合物。在這項研究中,我們報告在365納米光照下,金—二氧化鈦復(fù)合材料可在常溫條件下誘導(dǎo)氫分子異裂解離。
該過程可能依賴于光生電子與空穴在金屬金納米顆粒和金—氧—鈦界面支架上形成的界面電偶極矩。光照誘導(dǎo)的金納米顆粒表面氧化鈦層覆蓋進一步促進了氫的異裂解離。在流動反應(yīng)裝置中,光照射下產(chǎn)生的親核氫物種能以>99%的收率將二氧化碳還原為乙烷。
更重要的是,通過后續(xù)光催化乙烷脫氫反應(yīng)的級聯(lián),在超過1500小時的光照過程中實現(xiàn)了>99%收率的乙烯制備。
▲ Abstract:
Producing olefins by carbon dioxide (CO2) hydrogenation is a long-standing goal. The usual products are multicarbon mixtures because the critical step of heterolytic hydrogen (H2) dissociation at high temperatures complicates selectivity control. In this study, we report that irradiating gold–titanium dioxide at 365 nanometers induces heterolytic H2 dissociation at ambient temperature. This process likely relies on interfacial electric dipoles from photogenerated electrons and holes situated on the metallic gold nanoparticles and interfacial gold–oxygen–titanium scaffolds. The heterolytic H2 dissociation is further promoted by light-induced coating of gold nanoparticles with a titanium oxide layer. The resulting nucleophilic hydrogen species reduce CO2 to ethane in >99% yield under light irradiation in a flow apparatus. Furthermore, cascading with a subsequent photocatalytic ethane dehydrogenation generates ethylene in >99% yield over 1500 hours of irradiation.
生物學(xué)Biology
Epithelial tension controls intestinal cell extrusion
上皮細(xì)胞張力調(diào)控腸道細(xì)胞擠出機制
▲ 作者:Daniel Krueger, Willem Kasper Spoelstra et al.
▲ 鏈接:
https://www.science.org/doi/10.1126/science.adr8753
▲ 摘要:
細(xì)胞擠出對維持腸道上皮穩(wěn)態(tài)自我更新至關(guān)重要。腸道絨毛頂端細(xì)胞因擁擠導(dǎo)致的壓縮,曾被認(rèn)為是觸發(fā)擠出的主要因素。在這項研究中,我們發(fā)現(xiàn)腸道上皮中收縮細(xì)胞間局部的'拔河式'力學(xué)競爭才是調(diào)控細(xì)胞擠出的關(guān)鍵機制。
通過結(jié)合定量活體顯微技術(shù)、光遺傳學(xué)誘導(dǎo)組織張力、肌球蛋白II活性的遺傳干預(yù)以及小鼠腸道和腸道類器官中基底皮層局部破壞等技術(shù)手段,我們發(fā)現(xiàn)動態(tài)肌動球蛋白網(wǎng)絡(luò)在整個腸道絨毛(包括絨毛頂端區(qū)域)產(chǎn)生持續(xù)性張力。無法維持這種張力的機械弱勢細(xì)胞最終導(dǎo)致擠出的發(fā)生。因此,上皮屏障的完整性取決于細(xì)胞間的力學(xué)平衡。
▲ Abstract:
Cell extrusion is essential for homeostatic self-renewal of the intestinal epithelium. Extrusion is thought to be triggered by crowding-induced compression of cells at the intestinal villus tip. In this study, we found instead that a local “tug-of-war” competition between contractile cells regulated extrusion in the intestinal epithelium. We combined quantitative live microscopy, optogenetic induction of tissue tension, genetic perturbation of myosin II activity, and local disruption of the basal cortex in mouse intestines and intestinal organoids. These approaches revealed that a dynamic actomyosin network generates tension throughout the intestinal villi, including the villus tip region. Mechanically weak cells unable to maintain this tension underwent extrusion. Thus, epithelial barrier integrity depends on intercellular mechanics.
地球科學(xué)Earth Science
Very-long-range dynamic triggering of mud volcano unrest and silent magnitude-6 fault slip
極長程動態(tài)觸發(fā)作用導(dǎo)致泥火山活化與6級靜默斷層滑動
▲ 作者:Zaur Bayramov, Renier Viltres et al.
▲ 鏈接:
https://www.science.org/doi/10.1126/science.adv8438
▲ 摘要:
眾所周知,大地震產(chǎn)生的地震波能夠觸發(fā)遠(yuǎn)距離的斷層滑動,但其內(nèi)在機制尚不明確。通過采用干涉合成孔徑雷達技術(shù)并結(jié)合局部大地測量與地震數(shù)據(jù),我們發(fā)現(xiàn)2023年2月發(fā)生在土耳其東南部的卡赫拉曼馬拉什地震(震中距約1000公里)導(dǎo)致了西里海地區(qū)富含流體的庫拉盆地內(nèi)56處泥火山發(fā)生形變和/或噴發(fā),并在七條斷層上引發(fā)長達數(shù)十公里的厘米級靜默滑動。
這次等效矩震級達6.1的瞬態(tài)形變事件,與主要油氣田下方的局部隆升現(xiàn)象密切相關(guān)。我們推測地震波導(dǎo)致深層孔隙壓力變化,進而觸發(fā)沿盆地及周邊多條地殼斷層的靜默滑動。
▲ Abstract:
Seismic waves from large earthquakes are known to trigger slip on distant faults, but the underlying mechanisms remain unclear. Using interferometric synthetic aperture radar and local geodetic and seismic data, we show that the 1000-kilometer-distant, February 2023 Kahramanmara? earthquakes in southeastern Türkiye triggered deformation and/or eruption at 56 mud volcanoes and centimeter-scale aseismic slip on seven faults over tens of kilometers within the fluid-rich Kura Basin in the West Caspian region. This transient deformation event, with an equivalent moment magnitude of 6.1, was coupled with local inflation below major hydrocarbon fields. We postulate that seismic waves led to a change in pore pressure at depth, which in turn triggered aseismic slip along several crustal faults crossing the basin and its surroundings.
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