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Nuclear volume effects in kinetic isotope fractionation:A case study of mercury oxidation by chlorine species

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Acta Geochimica 2024年第3期43卷 411-423页

作者： Chenlu Yang Yining Zhang Yun Liu research center for planetary science College of Earth and Planetary SciencesChengdu University of TechnologyChengdu 610059China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

It is well-known that the equilibrium isotope fractionation of mercury(Hg)includes classical massdependent fractionations(MDFs)and nuclear volume effect(NVE)induced mass-independent fractionations(MIFs).However,the effect of the NVE on these kinetic processes is not known.The total fractionations(MDFs+NVEinduced MIFs)of several representative Hg-incorporated substances were selected and calculated with ab initio calculations in this work for both equilibrium and kinetic processes.NVE-induced MIFs were calculated with scaled contact electron densities at the nucleus through systematic evaluations of their accuracy and errors using the Gaussian09 and DIRAC19 packages(named the electron density scaling method).Additionally,the NVE-induced kinetic isotope effect(KIE)of Hg isotopes are also calculated with this method for several representative Hg oxidation reactions by chlorine species.Total KIEs for 202 Hg/^(198)Hg ranging from−2.27‰to 0.96‰are obtained.Three anomalous^(202)Hg-enriched KIEs(δ^(202)Hg/^(198)Hg=0.83‰,0.94‰,and 0.96‰,)caused by the NVE are observed,which are quite different from the classical view(i.e.,light isotopes react faster than the heavy ones).The electron density scaling method we developed in this study can provide an easier way to calculate the NVE-induced KIEs for heavy isotopes and serve to better understand the fractionation mechanisms of mercury isotope systems.

关键词： Nuclear volume effect Kinetic fractionation Hg isotopes Ab initio calculations

On-surface synthesis and characterization of polyynic carbon chains

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National science Review 2024年第3期11卷 192-199页

作者： Wenze Gao Wei Zheng Luye Sun Faming Kang Zheng Zhou Wei Xu Interdisciplinary Materials research center School of Materials Science and Engineering Tongji University

Carbyne, an elusive sp-hybridized linear carbon allotrope, has fascinated chemists and physicists for decades. Due to its high chemical reactivity and extreme instability, carbyne was much less explored in contrast to the sp2-hybridized carbon allotropes such as graphene. Herein, we report the on-surface synthesis of polyynic carbon chains by demetallization of organometallic polyynes on the Au（111） surface;the longest one observed consists of ～60 alkyne units（120 carbon atoms）. The polyynic structure of carbon chains with alternating triple and single bonds was unambiguously revealed by bond-resolved atomic force microscopy. Moreover, an atomically precise polyyne, C14, was successfully produced via tip-induced dehalogenation and ring-opening of the decachloroanthracene molecule(C14Cl10) on a bilayer NaCl/Au（111） surface at 4.7 K, and a band gap of 5.8 eV was measured by scanning tunnelling spectroscopy,in a good agreement with the theoretical HOMO–LUMO gap（5.48 eV）.

关键词： polyyne scanning probe microscopy carbon allotrope on-surface synthesis organometallic polyyne

Probing turbulence in galaxies with fast radio burst scintillation

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science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 177-178页

作者： James M.Cordes Department of Astronomy the Cornell Center for Astrophysics and Planetary ScienceCornell UniversityIthaca NY 14853USA

Interstellar scintillation(ISS)is a well-known phenomenon observed from pulsars in the Milky Way.It comprises intensity variations vs.time and frequency caused by constructive and destructive interference from multipath propagation,which is due to diffraction from fluctuations in electron density in the interstellar medium(ISM)on scales as small as~100 km.These density fluctuations appear to be part of a turbulence process combined with discrete structures in electron density from other astrophysical processes;together these fluctuations extend to scales of pc or larger.

关键词： scales galaxies turbulence

Cardiac energy metabolism disorder mediated by energy substrate imbalance and mitochondrial damage upon tebuconazole exposure

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Journal of Environmental sciences 2024年第2期136卷 270-278页

作者： Tingting Ku Jindong Hu Mengmeng Zhou Yuanyuan Xie Yutong Liu Xin Tan Lin Guo Guangke Li Nan Sang College of Environmental science and Resources Research Center of Environment and HealthShanxi UniversityTaiyuan 030006China

Tebuconazole exposure has been described as an increasing hazard to human health.An increasing number of recent studies have shown a positive association between tebuconazole exposure and cardiovascular disease risk,which is characterized by the reduction of adenosine triphosphate(ATP)synthesis.However,researches on the damage of tebuconazole exposure to energy metabolism and the related molecular mechanisms are limited.In the present study,male C57BL/6 mice were treated with tebuconazole at different low concentrations for 4 weeks.The results indicated that tebuconazole could accumulate in the heart and further induce the decrease of ATP content in the mouse heart.Importantly,tebuconazole induced an obvious shift in substrate utilization of fatty acid and glucose by disrupting their corresponding transporters(GLUT1,GLUT4,CD36,FABP3 and FATP1)expression,and significantly repressed the expression of mitochondrial biogenesis(Gabpa and Tfam)and oxidative phosphorylation(CS,Ndufa4,Sdhb,Cox5a and Atp5b)related genes in a dosedependent manner.Further investigation revealed that these alterations were related to the IRS1/AKT and PPARγ/RXRαpathways.These findings contribute to a better understanding of triazole fungicide-induced cardiovascular disease by revealing the key indicators associated with this phenomenon.

关键词： Tebuconazole Cardiotoxicity Energy metabolic disorders Energy substrate Mitochondrial damage

Zircon Zr isotope fractionation during crustal anatexis

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science China Earth sciences 2024年第8期67卷 2495-2506页

作者： Erlin ZHU Qiongxia XIA Zhaoya LI Renxu CHEN James VAN ORMAN School of Earth and Space sciences University of Science and Technology of China State Key Laboratory of Lithospheric and Environmental Coevolution Frontiers science center for planetary Exploration and Emerging Technologies University of Science and Technology of China Department of Earth Environmental and Planetary Sciences Case Western Reserve University

Zirconium is one of high field strength elements but its isotope behavior during geochemical processes is still uncertain because of the limited database. While Zr isotopes in magmatic rocks are often used to trace the evolution of magmas through fractional crystallization, it is intriguing how highly heterogeneous Zr isotopes were produced by the growth of zircon during crustal anatexis. We address this issue by in-situ zircon Zr isotope analyses of migmatites from two high-temperature metamorphic terranes in the South Lhasa zone and the North Dabie zone, respectively, in China. The results show highly variable δ94Zr values from-0.30‰ to +0.81‰ and from-0.58‰ to +0.49‰, respectively. In addition to the relict zircon of magmatic origin, two types of newly-grown zircons were identified in terms of their occurrences, trace elements and δ94Zr values. The peritectic zircon, mainly occurring in the in-situ leucosomes, exhibits the highest Nb-Ta-Hf-U contents and variably higher δ94Zr values than those of the relict zircon. The anatectic zircon, mainly occurring in the leucocratic veins, shows higher Nb-Ta-Hf-U contents than and similar δ94Zr values to those of the relict zircon. Model calculations demonstrate that the variable Zr isotope compositions of newly-grown zircons would result from decoupled release of Zr from zircon and non-zircon phases. The Zr supply of the peritectic zircon is mainly derived from the decomposition of Zr-bearing minerals in the in-situ anatectic melt（the non-zircon effect）, whereas the Zr supply of the anatectic zircon is mainly from the dissolution of pre-existing zircons in the evolved melt（the zircon effect）. The significant Zr isotope variations in the migmatites well illustrate the generation, migration and accumulation of the anatectic melts during the partial melting. Therefore, Zr isotopes can be used as a powerful means for distinguishing between the peritectic and anatectic zircons during crustal anatexis.

关键词： Zr isotopes Zircon effect Non-zircon effect Migmatite Crustal anatexis

Metallurgical performance evaluation of space-weathered Chang’e-5 lunar soil

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1241-1248页

作者： Chen Li Wenhui Ma Yang Li Kuixian Wei center for Lunar and planetary sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China

Space metallurgy is an interdisciplinary field that combines planetary space science and metallurgical engineering.It involves systematic and theoretical engineering technology for utilizing planetary resources in situ.However,space metallurgy on the Moon is challenging because the lunar surface has experienced space weathering due to the lack of atmosphere and magnetic field,making the mi-crostructure of lunar soil differ from that of minerals on the Earth.In this study,scanning electron microscopy and transmission electron microscopy analyses were performed on Chang’e-5 powder lunar soil samples.The microstructural characteristics of the lunar soil may drastically change its metallurgical performance.The main special structure of lunar soil minerals include the nanophase iron formed by the impact of micrometeorites,the amorphous layer caused by solar wind injection,and radiation tracks modified by high-energy particle rays inside mineral crystals.The nanophase iron presents a wide distribution,which may have a great impact on the electromagnetic prop-erties of lunar soil.Hydrogen ions injected by solar wind may promote the hydrogen reduction process.The widely distributed amorph-ous layer and impact glass can promote the melting and diffusion process of lunar soil.Therefore,although high-energy events on the lun-ar surface transform the lunar soil,they also increase the chemical activity of the lunar soil.This is a property that earth samples and tradi-tional simulated lunar soil lack.The application of space metallurgy requires comprehensive consideration of the unique physical and chemical properties of lunar soil.

关键词： space metallurgy Chang’e-5 lunar soil space weathering metallurgical performance

Recent Advances in Patterning Strategies for Full‑Color Perovskite Light‑Emitting Diodes

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Nano-Micro Letters 2024年第3期16卷 99-137页

作者： Gwang Heon Lee Kiwook Kim Yunho Kim Jiwoong Yang Moon Kee Choi Graduate School of Semiconductor Materials and Devices Engineering Center for Future Semiconductor Technology(FUST)Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919Republic of Korea Department of Energy science and Engineering Daegu Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Republic of Korea Energy science and Engineering research center Daegu Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Republic of Korea Department of Materials science and Engineering Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919Republic of Korea center for Nanoparticle research Institute for Basic Science(IBS)Seoul 08826Republic of Korea

Metal halide perovskites have emerged as promising light-emitting materials for next-generation displays owing to their remarkable material characteristics including broad color tunability,pure color emission with remarkably narrow bandwidths,high quantum yield,and solution processability.Despite recent advances have pushed the luminance efficiency of monochromic perovskite light-emitting diodes(PeLEDs)to their theoretical limits,their current fabrication using the spincoating process poses limitations for fabrication of full-color displays.To integrate PeLEDs into full-color display panels,it is crucial to pattern red–green–blue(RGB)perovskite pixels,while mitigating issues such as cross-contamination and reductions in luminous efficiency.Herein,we present state-of-the-art patterning technologies for the development of full-color PeLEDs.First,we highlight recent advances in the development of efficient PeLEDs.Second,we discuss various patterning techniques of MPHs(i.e.,photolithography,inkjet printing,electron beam lithography and laserassisted lithography,electrohydrodynamic jet printing,thermal evaporation,and transfer printing)for fabrication of RGB pixelated displays.These patterning techniques can be classified into two distinct approaches:in situ crystallization patterning using perovskite precursors and patterning of colloidal perovskite nanocrystals.This review highlights advancements and limitations in patterning techniques for PeLEDs,paving the way for integrating PeLEDs into full-color panels.

关键词： Perovskite Light-emitting diode Full-color display High-resolution patterning Electroluminescence

A wide-linear-range and low-hysteresis resistive strain sensor made of double-threaded conductive yarn for human movement detection

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Journal of Materials science & Technology 2024年第5期172卷 202-212页

作者： Fei Huang Jiyong Hu Xiong Yan Shanghai Frontier science research center for Modern Textiles Donghua UniversityShanghai 201620China

Yarn-based flexible strain sensors with advantages in wearability and integrability have attracted wide at-tention.However,it is still a big challenge to achieve yarn-based strain sensors with a wide linear strain range,low hysteresis,and durability synchronously that can be used for full range detection of human body motions.Herein,a new structure,double-threaded conductive yarn with rhythmic strain distribu-tion,is reported to markedly widen the linear strain range of microcrack-based stretchable strain sensors.A new method of winding and thermally adhering hot-melt filaments on the surface of the elastic fiber is used to achieve double-threaded yarn(DTY)with rhythmic strain distribution.The proposed strategy,the integration of heterogeneous materials,is reported to significantly reduce the mechanical hysteresis of composite yarns.Rhythmic strain distribution of the DTY during stretching causes multi-level micro-cracks in different regions of the carbon nanotube(CNT)conductive layer deposited on the surface of the DTY.Besides,the sensing performance of DTY-based strain sensor can be adjusted by designing the structural parameters.The final prepared flexible strain sensor has the advantages of a wide linear strain range(100%),great sensitivity(GF=12.43),low hysteresis,rapid response(158 ms),high repeatability(>2000 cycles at 50%strain),and hydrophobicity,etc.The sensor can monitor human motion repeatedly and stably well,and shows great advantages in flexible wearable devices.

关键词： Double-threaded yarn Strain redistribution Hysteresis Human motion monitoring

Steric hindrance modulation of hexaazatribenzanthraquinone isomers for high-capacity and wide-temperature-range aqueous proton battery

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National science Review 2024年第4期11卷 271-282页

作者： Mingsheng Yang Yuxin Hao Bei Wang Yan Wang Liping Zheng Rui Li Huige Ma Xinyu Wang Xiaoming Jing Hongwei Li Mengxiao Li Zhihui Wang Yujie Dai Guangcun Shan Mingjun Hu Jun Luo Jun Yang School of Materials science and Engineering Beihang University Beijing Institute of Nanoenergy &Nanosystems Chinese Academy of Sciences center on Nanoenergy research School of Physical Science & TechnologyGuangxi University School of Chemistry and Chemical Engineering Center on Nanoenergy Research Guangxi University School of Instrumentation science and Opto-electronics Engineering Beihang University ShenSi Lab Shenzhen Institute for Advanced StudyUniversity of Electronic Science and Technology of China

Organic materials with rich active sites are good candidates of high-capacity anodes in aqueous batteries,but commonly low utilization of active sites limits their capacity.Herein,two isomers,symmetric and asymmetric hexaazatribenzanthraquinone（s-HATBAQ and a-HATBAQ）,with rich active sites have been synthesized in a controllable manner.It has been revealed for the first time that a sulfuric acid catalyst can facilitate the stereoselective formation of s-HATBAQ.Attributed to the reduced steric hindrance in favor of proton insertion as well as the amorphous structure conducive to electrochemical dynamics,s-HATBAQ exhibits 1.5 times larger specific capacity than a-HATBAQ.Consequently,the electrode of s-HATBAQ with50% reduced graphene oxide（s-HATBAQ-50%rGO） delivers a record high specific capacity of405 mAh g-1in H2SO4electrolyte.Moreover,the assembled MnO2//s-HATBAQ-50%rGO aqueous proton full batteries show an exceptional cycling stability at 25℃ and can maintain ～92% capacity after1000 cycles at 0.5 A g-1at-80℃.This work demonstrates the controllable synthesis of isomers,showcases a wide-temperature-range prototype proton battery and highlights the significance of precise mole cular structure modulation in organic energy storage.

关键词： stereoisomers steric effect aqueous battery super cycling stability ultra-low temperature proton battery