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Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

Tungsten 2025年第1期7卷 88-99页

作者： Yu-Jing Weng Zhao-Ying Ding Ying-Chao Li Yuan-Feng Wu Yuan-Yang Xu Rui Chen Xiao-Lei Zhao Hai-Yong Wang Da-Lei Zhang Yu-Long Zhang Henan Key Laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

关键词： Cellulosic ethanol Chem-catalysis Hydrogenolysis Retro-aldol condensation Tungsten

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Nitrogen addition promotes soil carbon accumulation globally

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Science China Life Sciences 2025年第1期68卷 284-293页

作者： Xuemei Yang Suhui Ma Erhan Huang Danhua Zhang Guoping Chen Jiangling Zhu Chengjun Ji Biao Zhu Lingli Liu Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China School of Ecology and Environmental ScienceYunnan University State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences

Soil is the largest carbon(C) reservoir in terrestrial ecosystems and plays a crucial role in regulating the global C cycle and climate *** nitrogen(N) deposition has been widely considered as a critical factor affecting soil organic carbon(SOC) storage, but its effect on SOC components with different stability remains unclear. Here, we analyzed extensive empirical data from 304 sites worldwide to investigate how SOC and its components respond to N addition. Our analysis showed that N addition led to a significant increase in bulk SOC(6.7%), with greater increases in croplands(10.6%) and forests(6.0%) compared to grasslands(2.1%). Regarding SOC components, N addition promoted the accumulation of plant-derived C(9.7%–28.5%) over microbial-derived C(0.2%), as well as labile(5.7%) over recalcitrant components(–1.2%), resulting in a shift towards increased accumulation of plant-derived labile C. Consistently, N addition led to a greater increase in particulate organic C(11.9%) than mineral-associated organic C(3.6%), suggesting that N addition promotes C accumulation across all pools, with more increase in unstable than stable pools. The responses of SOC and its components were best predicted by the N addition rate and net primary productivity. Overall, our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated C and a subsequent decrease in the overall stability of soil C pool, which underscores the importance of considering the effects of N enrichment on SOC components for a better understanding of C dynamics in soils.

关键词： meta-analysis nitrogen enrichment soil organic carbon carbon accumulation carbon stability

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Wafer‑Scale Ag_(2)S‑Based Memristive Crossbar Arrays with Ultra‑Low Switching‑Energies Reaching Biological Synapses

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Nano-Micro Letters 2025年第3期17卷 328-339页

作者： Yuan Zhu Tomas Nyberg Leif Nyholm Daniel Primetzhofer Xun Shi Zhen Zhang Division of Solid‑State Electronics Department of Electrical EngineeringUppsala University75121 UppsalaSweden Department of Chemistry Uppsala UniversityUppsalaSweden Department of Physics and Astronomy Uppsala UniversityUppsalaSweden State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China

Memristive crossbar arrays(MCAs)offer parallel data storage and processing for energy-efficient neuromorphic ***,most wafer-scale MCAs that are compatible with complementary metal-oxide-semiconductor(CMOS)technology still suffer from substantially larger energy consumption than biological synapses,due to the slow kinetics of forming conductive paths inside the memristive *** we report wafer-scale Ag_(2)S-based MCAs realized using CMOS-compatible processes at temperatures below 160℃.Ag_(2)S electrolytes supply highly mobile Ag+ions,and provide the Ag/Ag_(2)S interface with low silver nucleation barrier to form silver filaments at low energy *** further enhancing Ag+migration in Ag_(2)S electrolytes via microstructure modulation,the integrated memristors exhibit a record low threshold of approximately−0.1 V,and demonstrate ultra-low switching-energies reaching femtojoule values as observed in biological *** low-temperature process also enables MCA integration on polyimide substrates for applications in flexible ***,the intrinsic nonidealities of the memristive units for deep learning can be compensated by employing an advanced training *** impressive accuracy of 92.6%in image recognition simulations is demonstrated with the MCAs after the *** demonstrated MCAs provide a promising device option for neuromorphic computing with ultra-high energy-efficiency.

关键词： Wafer-scale Ag_(2)S films Reactive sputter Silver nucleation Ag^(+)migration Energy-efficient neuromorphic computing

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Spatiotemporal characteristics and influencing factors of vegetation water use efficiency on the Tibetan Plateau in 2001–2020

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Journal of Geographical Sciences 2025年第1期35卷 39-64页

作者： HE Chenyang WANG Yanjiao YAN Feng LU Qi School of Ecological and Environmental Science East China Normal University Institute of Ecological Conservation and Restoration Chinese Academy of Forestry National Climate Center China Meteorological Administration

Water use efficiency （WUE）,as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ***,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain *** study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–*** indicated an annual mean WUE of 0.8088 gC/mm·m2across the plateau,with a spatial gradient reflecting decrease from the southeast toward the *** manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,***,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of *** factors accounted for 70.79%of the variability in *** leaf area index and temperature served as the major driving forces of WUE variation.

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Resting-state brain network remodeling after different nerve reconstruction surgeries:a functional magnetic resonance imaging study in brachial plexus injury rats

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Neural Regeneration Research 2025年第5期20卷 1495-1504页

作者： Yunting Xiang Xiangxin Xing Xuyun Hua Yuwen Zhang Xin Xue Jiajia Wu Mouxiong Zheng He Wang Jianguang Xu School of Rehabilitation Science Shanghai University of Traditional Chinese MedicineShanghaiChina Engineering Research Center of Traditional chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghaiChina Department of Rehabilitation Medicine Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina Department of Traumatology and Orthopedics Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghaiChina Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence(Fudan university) Ministry of EducationShanghaiChina Human Phenome Institute Fudan UniversityShanghaiChina

Distinct brain remodeling has been found after different nerve reconstruction strategies,including motor representation of the affected ***,differences among reconstruction strategies at the brain network level have not been *** study aimed to explore intranetwork changes related to altered peripheral neural pathways after different nerve reconstruction surgeries,including nerve repair,endto-end nerve transfer,and end-to-side nerve ***–Dawley rats underwent complete left brachial plexus transection and were divided into four equal groups of eight:no nerve repair,grafted nerve repair,phrenic nerve end-to-end transfer,and end-to-side transfer with a graft sutured to the anterior upper ***-state brain functional magnetic resonance imaging was obtained 7 months after *** independent component analysis algorithm was utilized to identify group-level network components of interest and extract resting-state functional connectivity values of each voxel within the *** in intra-network resting-state functional connectivity were compared among the *** muscle reinnervation was assessed by behavioral observation(elbow flexion)and *** results showed that alterations in the sensorimotor and interoception networks were mostly related to changes in the peripheral neural *** repair was related to enhanced connectivity within the sensorimotor network,while end-to-side nerve transfer might be more beneficial for restoring control over the affected limb by the original motor *** thalamic-cortical pathway was enhanced within the interoception network after nerve repair and end-to-end nerve *** areas related to cognition and emotion were enhanced after end-to-side nerve *** study revealed important brain networks related to different nerve *** networks may be potential targets for enhancing motor recovery.

关键词： brain functional networks end-to-end nerve transfer end-to-side nerve transfer independent component analysis nerve repair peripheral plexus injury resting-state functional connectivity

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Investigation of edge states variation in valley photonic crystals by modulating the refractive index of domain walls

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Optoelectronics Letters 2025年第3期21卷 160-166页

作者： ZHANG Run ZHONG Xingli LIN Zhongxi QIU Weibin SU Hui Key Laboratory of Optoelectronic Materials Chemistry and Physics Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices Fujian Institute of Research on the Structure of Matter Chinese Academy of Science university of chinese academy of Sciences Chinese Academy of Sciences College of Information Science and Engineering Huaqiao University Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China

Realizing the valley Hall effect by breaking the spatial inversion symmetry of photonic systems has become a cutting-edge field of micro-nano-optics, since the valley degree of freedom was introduced into photonic system. Various novel devices based on the domain walls of the valley photonic crystals have also been demonstrated. In this article,we investigate the variation of edge states by the modulation of refractive index within the domain walls, and the geometric difference between the dielectric columns of the sublattices. Straight photonic crystal waveguides with three types of domain walls (bearded, zigzag, armchair) are constructed. Simulation results show that the creation of a double-edge state in the band diagram results in two windows of stable transmission in tunable bands. Our findings might have significant implications in the field of novel optical devices.

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一维范德华原子链材料的研究进展（英文）

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Science China Materials 2025年

作者：占鹏鑫贺平王子珂罗灵心崔雪萍郑健 Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences university of chinese academy of Sciences

由于量子限域效应的影响,石墨烯等二维(2D)材料表现出独特而卓越的性能,突显了低维材料在基础研究和实际应用中的重要性.这导致人们对具有更低维度的一维(1D)范德华原子链材料抱有很高的期望.与二维材料相比,一维范德华原子链在两个维...

由于量子限域效应的影响,石墨烯等二维(2D)材料表现出独特而卓越的性能,突显了低维材料在基础研究和实际应用中的重要性.这导致人们对具有更低维度的一维(1D)范德华原子链材料抱有很高的期望.与二维材料相比,一维范德华原子链在两个维度上都达到了物理极限,从而产生了更明显的量子限域效应,引发了意想不到的物理现象,并将建立一个全新的探索领域.本文综述了一维范德华原子链材料的研究进展.首先,我们总结了一维范德华原子链材料的各种类型和结构.随后,我们讨论了他们的制备和表征方法.最后,我们展望了一维范德华原子链材料在未来发展中将面临的挑战以及机遇.

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Multi-dimensional Bi@C electrocatalyst for Cr3+/Cr2+ redox reaction boosting high-performance iron-chromium flow batteries

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Science China Chemistry 2025年

作者： Min Wu Mingjun Nan Shumin Liu Caihe Zhong Lin Qiao Huamin Zhang Xiangkun Ma Department of Materials Science and Engineering Dalian Maritime University Division of Energy Storage Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences

With the increasing demand for energy storage technology, iron-chromium flow batteries（ICFBs） have been widely concerned because of their price advantage. However, the low electrochemical activity of Cr3+/Cr2+redox couples and the side hydrogen evolution reaction limit the industrial application of ICFBs. A multi-dimensional Bi/carbon composite electrocatalyst（Bi@C）for ICFB is designed and prepared to improve the electrochemical activity of Cr3+/Cr2+redox couples. Benefiting by using the Bimetal organic framework（Bi-MOF） with solid matrix as precursors, Bi nanospheres are highly dispersed on the Bi@C electrocatalyst that effectively enhances the electrochemical activity. The special morphology of Bi@C electrocatalyst helps the transfer of electrons and ions, significantly reducing the polarization of battery. Herein, the 3D porous carbon frames accelerate mass transfer, and the 2D carbon nanobelts and carbon layer coating on 0D Bi nanospheres improve the conductivity of Bi nanospheres. Therefore, the ICFB with multi-dimensional Bi@C electrocatalyst exhibits coulombic efficiency of 98.10% and energy efficiency of 79.14% at 140 mA cm-2, which is higher than ICFBs with commercial graphite carbon electrocatalyst and with heat treatment carbon felt. This work provides a simple and economical method to fabricate a high-performance multidimensional Bi@C electrocatalyst for Cr3+/Cr2+redox couples, boosting the development of ICFBs.

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Constructing quasi-2D perovskite to collect hot carriers to reduce open-circuit voltage loss for efficient inverted perovskite solar cells

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Science China Chemistry 2025年

作者： Lei Gu Xing Li Chao Wu Yang Feng Chunming Yang Lin Song Frontiers Science Center for Flexible Electronics Institute of Flexible Electronics Northwestern Polytechnical University Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences

Inverted perovskite solar cells （PSCs） have received great attention owing to the high certificated power conversion efficiency（PCE） reaching 26.7%. However, interfacial charge recombination is far superior to perovskite bulk charge recombination due to the use of fullerenes and their derivatives in inverted perovskite solar cells, which induces devastating open circuit voltage（VOC） losses. For this reason the present work attempts to use 4-chloropiperidine hydrochloride for the upper surface modification of perovskite to construct a quasi-two-dimensional （2D） structure with suitable 2D layer widths （n=2, 3 dominant）,which has a smaller electron carrier transport barrier without sacrificing short-circuit current （JSC） in the device. This strategy effectively passivates the interfacial defect states while promoting energy level alignment to achieve carrier dissociation and equilibrium transport at the interface, which in turn resulted in improved fill factor （FF）. In addition, additional energy levels are provided by 2D perovskites to collect hot carriers, resulting in improved device open circuit voltage （VOC）. As a result, the device PCE increases from 22.37%to 24.11%after the 4CPD treatment. In addition, the 4CPD-treated PSCs maintain 90%of the initial PCE after storage in an N2atmosphere at 50°C for 1,080 h, whereas the control devices show a 15%PCE loss under the same aging conditions. This work provides new opportunities to suppress interfacial charge recombination in inverted devices.

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Accurate quantification of the algebraic,multiplicative algebraic,and simultaneous iterative reconstruction techniques in ionosphere rebuilding based on the TIEGCM assessment

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Earth and Planetary Physics 2025年第1期9卷 117-126页

作者： Ao Qi HaiBing Ruan Institute of Space Weather Nanjing University of Information Science and TechnologyNanjing 210044China Key Laboratory of Geospace Environment University of Science&Technology of ChinaChinese Academy of SciencesHefei 230026China

The algebraic reconstruction technique(ART),multiplicative algebraic reconstruction technique(MART),and simultaneous iterative reconstruction technique(SIRT)are computational methodologies extensively utilized within the field of computerized ionospheric tomography(CIT)to facilitate three-dimensional reconstruction of the ionospheric ***,reconstruction accuracy elicits recurrent disputes over its practical application,and people usually attribute this issue to incomplete and uneven coverage of the *** Thermosphere Ionosphere Electrodynamics General Circulation Model(TIEGCM)offers a reasonable physics-based ionospheric background and is widely utilized in ionospheric *** use the TIEGCM simulations as the targeted ionosphere because the current measurements are far from able to realistically reproduce the ionosphere in *** designations of satellite measurements are conducted to investigate the limiting performance of CIT methods in ionospheric *** to common practice,electron density distributions from outputs of the International Reference Ionosphere(IRI)model are used as the iterative initial value in CIT *** outcomes suggest that despite data coverage,iterative initial conditions also play an essential role in ionospheric *** particular,in the longitudinal sectors where the iterative initial height of the F2-layer peak electron density(hmF2)differs substantially from the background densities,none of the three CIT methods can reproduce the exact background *** hmF2 is close but the ionospheric F2-layer peak density(NmF2)is different between the targeted background and initial conditions,the MART performs better than the ART and SIRT,as evidenced by the correlation coefficients of MART being above 0.97 and those of ART and SIRT being below *** summary,this investigation reveals the potential uncertainties in traditional CIT reconstruction,particularly when reali

关键词： computerized ionospheric tomography International Reference Ionosphere model Thermosphere Ionosphere Electrodynamics General Circulation model ionosphere

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