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Ru-doped functional porous materials for electrocatalytic water splitting

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Nano Research 2024年第3期17卷 982-1002页

作者： Chongao Tian Rui Liu yu zhang.wenxiu yang.bo wang Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials Advanced Technology Research Institute(Jinan)Advanced Research Institute of Multidisciplinary ScienceSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Library Beijing Institute of TechnologyBeijing 100081China

Electrolytic water splitting(EWS)is an attractive and promising technique for the production of hydrogen ***,the sluggish kinetic rate of hydrogen/oxygen evolution reactions leads to a high overpotential and low energy *** to date,Pt/Ir-based nanocatalysts have become the state-of-the-art EWS catalysts,but disadvantages such as high cost and low earth abundance greatly limit their applications in EWS *** an attractive candidate for the Pt/Ir catalysts,series of Ru-based nanomaterials have aroused much attention for their low price,Pt-like hydrogen bond strength,and high EWS *** particular,Ru-doped functional porous materials have been becoming one of the most representative EWS catalysts,which can not only achieve the dispersion and adjustment for active Ru sites,but also simultaneously solve the problems of mass transfer and catalytic conversion in *** this review,the design and preparation strategies of Ru-doped functional porous materials toward EWS in recent years are summarized,including Ru-doped metal organic frameworks(MOFs),Ru-doped porous organic polymers(POPs),and their ***,detailed structure–activity relationships induced by the tuned geometric/electronic structures of Ru-doped functional porous materials are further depicted in this *** but not least,the challenges and perspectives of Ru-doped functional porous materials catalysts are reasonably proposed to provide fresh ideas for the design of Ru-based EWS catalysts.

关键词： Ru-based catalyst functional porous materials electrolytic water splitting oxygen evolution reaction hydrogen evolution reaction

Protein crystallization with DNA templates

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Particuology 2024年第3期86卷 262-268页

作者： bo zhang Jia yu Zhe Pu Wenhui Guo Ruoqi yang yu Wen Zhijiang Rong Hui wang Xiaoli Wu bo wang Hongyan Sun School of Environment and Resources Taiyuan University of Science and TechnologyTaiyuan030024China School of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan030024China

Protein crystallization plays a significant role in three-dimensional structural analysis and protein *** is important to increase the crystallization efficiency,which is possible by adding hetero-geneous templates in crystallization *** is biologically compatible and artificially designable polymer,which is easy to *** this study,single-and double-stranded DNA of precise sequences were designed and used as templates to promote protein crystallization of lysozyme and ***-fluence of DNA,single-stranded DNA with 10,20,40 bases and double-stranded DNA with 10,20,40 base pairs,were *** success rate of obtaining crystals of lysozyme and catalase in equal period was significantly improved with the addition of DNA comparing without templates ***-stranded DNA led to higher nucleation rate than that with single-stranded *** promotion of nucleation was more obvious at low concentration of protein solution and with longer chain DNA *** number and crystallization rate was enhanced with addition of long double-stranded DNA *** the results confirm that DNA is an effective polymer additive to enhance protein crystallization,especially for the application of the scarce protein crystallization.

关键词： DNA Polymer Additive Protein Crystallization

Chemical modification of barite for improving the performance of weighting materials for water-based drilling fluids

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Petroleum Science 2024年第1期21卷 551-566页

作者： Li-Li yang Ze-yu Liu Shi-bo wang Xian-bo He Guan-Cheng Jiang Jie zhang MOE Key Laboratory of Petroleum Engineering State Key Laboratory of Petroleum Resources and ProspectingChina University of Petroleum(Beijing)Changping DistrictBeijing102249China MOE Key CNPC Drilling Research Institute Changping DistrictBeijing102206China

With increasing drilling depth and large dosage of weighting materials,drilling fluids with high solid content are characterized by poor stability,high viscosity,large water loss,and thick mud cake,easier leading to reservoir damage and wellbore *** this paper,micronized barite(MB)was modified(mMB)by grafting with hydrophilic polymer onto the surface through the free radical polymerization to displace conventional API barite *** suspension stability of water-based drilling fluids(WBDFs)weighted with API barite:mMB=2:1 in 600 g was significantly enhanced compared with that with API barite/WBDFs,exhibiting the static sag factor within 0.54 and the whole stability index of *** viscosity and yield point reached the minimum,with a reduction of more than 40%compared with API barite only at the same *** multi-stage filling and dense accumulation of weighting materials and clays,filtration loss was decreased,mud cake quality was improved,and simultaneously it had great reservoir protection performance,and the permeability recovery rate reached 87%.In addition,it also effectively improved the lubricity of *** sticking coefficient of mud cake was reduced by 53.4%,and the friction coefficient was ***,mMB can serve as a versatile additive to control the density,rheology,filtration,and stability of WBDFs weighted with API barite,thus regulating comprehensive performance and achieving reservoir protection *** work opened up a new path for the productive drilling of extremely deep and intricate wells by providing an efficient method for managing the performance of high-density WBDFs.

关键词： Drilling fluids Weighting materials Filtration control Reservoir protection Stability property

Semi-supervised remote sensing image scene classification with prototype-based consistency

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Chinese Journal of Aeronautics 2024年第2期37卷 459-470页

作者： yang LI zhang LI Zi wang Kun wang Qifeng yu College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Deep learning significantly improves the accuracy of remote sensing image scene classification,benefiting from the large-scale ***,annotating the remote sensing images is time-consuming and even tough for *** neural networks trained using a few labeled samples usually generalize less to new unseen *** this paper,we propose a semi-supervised approach for remote sensing image scene classification based on the prototype-based consistency,by exploring massive unlabeled *** this end,we,first,propose a feature enhancement module to extract discriminative *** is achieved by focusing the model on the foreground ***,the prototype-based classifier is introduced to the framework,which is used to acquire consistent feature *** conduct a series of experiments on NWPU-RESISC45 and Aerial Image Dataset(AID).Our method improves the State-Of-The-Art(SOTA)method on NWPU-RESISC45 from 92.03%to 93.08%and on AID from 94.25%to 95.24%in terms of accuracy.

关键词： Semi-supervised learning Remote sensing Scene classification Prototype network Deep learning

Manipulating Crystal Growth and Secondary Phase PbI_(2)to Enable Efficient and Stable Perovskite Solar Cells with Natural Additives

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Nano-Micro Letters 2024年第9期16卷 432-448页

作者： Yirong wang Yaohui Cheng Chunchun Yin jinming zhang Jingxuan You Jizheng wang Jinfeng wang Jun zhang Institute of Chemistry Chinese Academy of Sciences(CAS)Beijing 100190People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Nanjing University Nanjing 210023People’s Republic of China Wuhan Textile University Wuhan 430200People’s Republic of China

In perovskite solar cells(PSCs),the inherent defects of perovskite film and the random distribution of excess lead iodide(PbI_(2))prevent the improvement of efficiency and ***,natural cellulose is used as the raw material to design a series of cellulose derivatives for perovskite crystallization *** cationic cellulose derivative C-Im-CN with cyano-imidazolium(Im-CN)cation and chloride anion prominently promotes the crystallization process,grain growth,and directional orientation of ***,excess PbI_(2)is transferred to the surface of perovskite grains or formed plate-like crystallites in local *** effects result in suppressing defect formation,decreasing grain boundaries,enhancing carrier extraction,inhibiting non-radiative recombination,and dramatically prolonging carrier ***,the PSCs exhibit a high power conversion efficiency of 24.71%.Moreover,C-Im-CN has multiple interaction sites and polymer skeleton,so the unencapsulated PSCs maintain above 91.3%of their initial efficiencies after 3000 h of continuous operation in a conventional air atmosphere and have good stability under high humidity *** utilization of biopolymers with excellent structure-designability to manage the perovskite opens a state-of-the-art avenue for manufacturing and improving PSCs.

关键词： Perovskite Solar cells Defect passivation Biomass additives Crystal orientation

Investigation of control effects of end-wall selfadaptive jet on three-dimensional corner separation of a highly loaded compressor cascade

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Chinese Journal of Aeronautics 2024年第6期37卷 109-126页

作者： Hejian wang bo LIU Xiaochen MAO botao zhang Zonghao yang School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China The National Key Laboratory of Science and Technology on Aerodynamic Design and Research Xi’an 710129China Taihang Laboratory Chengdu 610000China

To overcome the limitations posed by three-dimensional corner separation,this paper proposes a novel flow control technology known as passive End-Wall(EW)self-adaptive *** single EW slotted schemes(EWS1 and EWS2),alongside a combined(COM)scheme featuring double EW slots,were *** results reveal that the EW slot,driven by pressure differentials between the pressure and suction sides,can generate an adaptive jet with escalating velocity as the operational load *** high-speed jet effectively re-excites the local low-energy fluid,thereby mitigating the corner ***,the EWS1 slot,positioned near the blade leading edge,exhibits relatively low jet velocities at negative incidence angles,causing jet separation and exacerbating the corner ***,the EWS2 slot is close to the blade trailing edge,resulting in massive low-energy fluid accumulating and separating before the slot outlet at positive incidence *** contrast,the COM scheme emerges as the most effective solution for comprehensive corner separation *** can significantly reduce the total pressure loss and improve the static pressure coefficient for the ORI blade at 0°-4° incidence angles,while causing minimal negative impact on the aerodynamic performance at negative incidence ***,the corner stall is delayed,and the available incidence angle range is broadened from -10°--2°to -10°-4°.This holds substantial promise for advancing the aerodynamic performance,operational stability,and load capacity of future highly loaded compressors.

关键词： Three-dimensional corner separation End-wall adaptive jet Total pressure loss Highly loaded compressor cascade Compressors

Complicated flow in tip flow field of a compressor tandem cascade using delayed detached eddy simulation

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Chinese Journal of Aeronautics 2024年第8期37卷 63-78页

作者： botao zhang Xiaochen MAO bo LIU Hejian wang Zonghao yang School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China Taihang Laboratory Chengdu 610000China

The complex flow characteristics in the tip region of a tandem cascade with tip clearance have been calculated and analyzed using Delayed Detached Eddy Simulation(DDES).The coherent mechanism of the vortex structures near the blade tip was discussed,and the unsteady behaviors and features in the tip flow field were ***,the interaction between the tip leakage flow and the gap jet was *** results show that,compared to the datum cascade,the blade tip load of the rear blade increases while that of the front blade *** fluctuations of the tandem cascade are mainly caused by the interaction between the tip leakage flow and gap jet,and by the mixing of the vortex structures,but there is no essential change in the spectrum feature of the tip leakage ***,a detailed analysis of the development of vortices in the tip region is conducted by the topological structures of the flow *** with the three-dimensional vortex structures,the schematic diagram of the vortex system of the datum single-row cascade and tandem cascade is summarized.

关键词： Tandem cascade Tip leakage flow Delayed Detached Eddy Simulation(DDES) Unsteady flow Gap jet Topological structure

Zero-Dynamics Attacks for Multi-Agent Systems Without Velocity Measurements

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Journal of Systems Science & Complexity 2024年第5期37卷 1809-1831页

作者： GAO jinming wang Yijing ZUO Zhiqiang zhang Wentao Tianjin Key Laboratory of Intelligent Unmanned Swarm Technology and System School of Electrical and Information Engineering Tianjin University Continental-NTU Corporate Lab School of Electrical and Electronic Engineering Nanyang Technological University

This paper studies the periodic zero-dynamics attacks(ZDAs) in multi-agent systems without velocity measurements under directed graph. Specifically, two types of attack modes are addressed,i.e., infinite number and finite number of zero-dynamics attacks. For the former case, the authors show that the consensus of the considered system cannot be guaranteed. For the latter case, the dynamic evolution of the agents is investigated and it is found that only attacking the rooted agents can destroy the consensus. Then, a sufficient condition which quantifies whether or not the consensus value is destroyed is given, revealing the relationship among parameters of system model, filter and attack ***, simulations are carried out to verify the effectiveness of the theoretical findings.

关键词： Consensus directed graph multi-agent systems zero-dynamics attacks

Prospects of the Multi-channel Photometric Survey Telescope in the Cosmological Application of Type Ia Supernovae

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Research in Astronomy and Astrophysics 2024年第4期24卷 183-191页

作者： Zhenyu wang Jujia zhang Xinzhong Er jinming Bai yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China International Centre of Supernovae Yunnan Key LaboratoryKunming 650216China South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China

The Multi-channel Photometric Survey Telescope(Mephisto)is a real-time,three-color photometric system designed to capture the color evolution of stars and transients *** telescope system can be crucial in cosmological distance measurements of low-redshift(low-z,z■0.1)Type Ia supernovae(SNe Ia).To optimize the capabilities of this instrument,we perform a comprehensive simulation study before its official operation is scheduled to *** considering the impact of atmospheric extinction,weather conditions,and the lunar phase at the observing site involving the instrumental features,we simulate light curves of SNe Ia obtained by *** best strategy in the case of SN Ia cosmology is to take the image at an exposure time of 130 s with a cadence of 3 *** this condition,Mephisto can obtain hundreds of high-quality SNe Ia to achieve a distance measurement better than 4.5%.Given the on-time spectral classification and monitoring of the Lijiang 2.4 m Telescope at the same observatory,Mephisto,in the whole operation,can significantly enrich the well-calibrated sample of supernovae at low-z and improve the calibration accuracy of high-z SNe Ia.

关键词： (stars:)supernovae:general (cosmology:)cosmological parameters telescopes