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Science China Chemistry 2023年第3期66卷 739-754页

作者： Baowen Zhou Jinglin Li Xinyue Dong Lin Yao Key Laboratory for Power Machinery and Engineering of Ministry of Education School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China China-UK Low Carbon College Shanghai Jiao Tong UniversityShanghai 201306China

Photoelectrocatalytic(PEC)production of fuels and chemicals by using solar energy,water,and CO_(2) paves a promising avenue toward carbon neutrality.Over the past decades,for accelerating this process,a variety of photocathodes have been explored.Among them,the hybrid of GaN nanowires(NWs)and planar silicon has appeared as a disruptive platform for this grand topic,owing to their distinctive structural,optoelectronic,and catalytic properties.This review illustrates the most recent advances in GaN NWs/Si-based photocathodes for CO_(2) reduction reactions powered by simulated sunlight,beginning with a discussion of the critical requirements and fundamental challenges of PEC CO_(2) reduction.The characteristics of GaN NWs/Si are then discussed,showing its great potential in precisely controlling the behavior of photons,charges,and chemical species.As the focus of this review,the progress on the PEC CO_(2) reduction reactions toward different products over GaN NWs/Si-based photocathodes is highlighted.In the end,the challenges and prospects of GaN NWs/Si-based photocathodes for the practical synthesis of solarfuels and chemicals are proposed.

关键词： GaN NWs/Si photocathodes solar fuels and chemicals CO reduction reactions

Recent advancements in single-cell metabolic analysis for pharmacological research

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Journal of Pharmaceutical Analysis 2023年第10期13卷 1102-1116页

作者： Ying Hou Hongren yao Jin-Ming lin Beijing Key Laboratory of Microanalytical Methods and Instrumentation Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology(Ministry of Education)Department of ChemistryTsinghua UniversityBeijing100084China

Cellular heterogeneity is crucial for understanding tissue biology and disease pathophysiology.Pharmacological research is being advanced by single-cell metabolic analysis,which offers a technique to identify variations in RNA,proteins,metabolites,and drug molecules in cells.In this review,the recent advancement of single-cell metabolic analysis techniques and their applications in drug metabolism and drug response are summarized.High-precision and controlled single-cell isolation and manipulation are provided by microfluidics-based methods,such as droplet microfluidics,microchamber,open microfluidic probe,and digital microfluidics.They are used in tandem with variety of detection techniques,including optical imaging,Raman spectroscopy,electrochemical detection,RNA sequencing,and mass spectrometry,to evaluate single-cell metabolic changes in response to drug administration.The advantages and disadvantages of different techniques are discussed along with the challenges and future directions for single-cell analysis.These techniques are employed in pharmaceutical analysis for studying drug response and resistance pathway,therapeutic targets discovery,and in vitro disease model evaluation.

关键词： Single-cell Metabolism Pharmacology Drug response Microfluidics

A noval iron-capturing nanocomposites against biofilms for disrupting bacterial nutritional balance

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Science China Chemistry 2024年第6期67卷 1760-1761页

作者： Jinying lin Qihang Ding yao Sun Department of Oral Implantology Jilin Provincial Key Laboratory of Tooth Development and Bone RemodelingSchool of StomatologyJilin UniversityChangchun130021China Department of Chemistry Korea UniversitySeoul02841Korea National Key Laboratory of Green Pesticide International Joint Research Center for Intelligent Biosensor Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhan430079China

Currently,the escalating crisis of bacterial infections and antibiotic resistance poses a significant global public health challenge[1-3].This situation has driven the search for novel antimicrobial strategies.Iron,a crucial micronutrient for bacterial growth,plays a vital role in metabolism,respiration,and various biochemical pathways[4-6].

关键词： metabolism resistance balance

Broadband Antireflective Superhydrophilic Thin Films with Outstanding Mechanical Stability on Glass Substrates

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Chinese Journal of Chemistry 2014年第6期32卷 507-512页

作者： Lin Yao Junhui He Functional Nanomaterials Laboratory and Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Graduate University of Chinese Academy of Sciences Beijing 100864China

A facile approach was developed to fabricate visible/near-infrared antireflective(AR),superhydrophilic and anti-fogging thin films on glass substrates.Glass substrate was first etched by H_(2)SiF_(6)-based vapor and then dip-coated sequentially in a base-catalyzed 20 nm SiO_(2)nanoparticles sol and an acid-catalyzed SiO_(2)sol.After an-nealing,the prepared thin film(named E/BSiO_(2)/ASiO_(2))not only showed good optical and wetting properties,but also exhibited excellent mechanical properties.The thin film has enhanced transmittance in the spectral range of UV to near-infrared.The maximum transmittance of E/BSiO_(2)/ASiO_(2)thin film coated glass substrate is 98.4%in 400-1200 nm and 96.1%in 1200-2500 nm,respectively.Comparing with blank glass substrate,the average transmittance increases by 5%in the wavelength range of 300-2500 nm.Meanwhile,the film showed good anti-fogging performance.SEM and AFM were employed to characterize the morphology of the thin film.The pre-pared thin film has potential application in various areas,like solar cells,windowpanes and eyeglasses,and may also find applications in membrane-based separation,selective catalysis and sensors.

关键词： etching antireflection superhydrophilicity anti-fogging mechanical properties

Seasonal Cumulative Effect of Ural Blocking Episodes on the Frequent Cold events in China during the Early Winter of 2020/21

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Advances in Atmospheric Sciences 2022年第4期39卷 609-624页

作者： yao yao Wenqi ZHANG Dehai LUO linhao ZHONG lin PEI Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100029China Institute of Urban Meteorology China Meteorological AdministrationBeijing 100029China

Starting in mid-November,China was hit by several cold events during the early winter of 2020/21.The lowest temperature observed at Beijing station on 7 January reached−19.6°C.In this paper,we show that the outbreak of the record-breaking extreme cold event can be attributed to a huge merging Ural blocking(UB)ridge over the Eurasian region.The sea-ice cover in the Kara and East Siberia Seas(KESS)in autumn was at its lowest value since 1979,which could have served as a precursor signal.Further analysis shows that several successive UB episodes occurred from 1 September 2020 to 10 January 2021.The persistent UB that occurred in late September/early October 2020 may have made an important contribution to the October historical minimum of sea ice in the KESS region.Our results also show that,after each UB episode in winter,significant upward propagation of wave activity occurred around 60°E,which resulted in weakening the stratospheric vortex.Meanwhile,each UB episode also caused a significant reduction in sea-ice extent in KESS and a significant weakening of the westerly jet in mid-high-latitude Eurasia.Results suggest that the Arctic vortex,which is supposed to enhance seasonally,became weaker and more unstable than the climatic mean under the seasonal cumulative effects of UB episodes,KESS warming,and long-lasting negative-phase North Atlantic Oscillation(NAO-).Those seasonal cumulative effects,combined with the impact of La Niña winter,led to the frequent occurrence of extreme cold events.

关键词： extreme cold events Ural blocking Arctic sea ice Arctic vortex cumulative effect

Quantifying the Spatial Characteristics of the Moisture Transport Affecting Precipitation Seasonality and Recycling Variability in Central Asia

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Advances in Atmospheric Sciences 2022年第6期39卷 967-984页

作者： linhao ZHONG Lijuan HUA Zhaohui GONG yao yao lin MU National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Key Laboratory of Computational Geodynamics College of Earth and Planetary SciencesUniversity of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China College of Life Sciences and Oceanography Shenzhen UniversityShenzhen 518060China

Moisture contribution and transport pathways for Central Asia(CA)are quantitatively examined using the Lagrangian water cycle model based on reanalysis and observational data to explain the precipitation seasonality and the moisture transport variation during 1979-2015.Westerly-related(northwesterly and westerly)transport explains 42%of CA precipitation and dominates in southwest CA,where precipitation is greatest in the cold season.Southeast CA,including part of Northwest China,experiences its maximum precipitation in the warm season and is solely dominated by southerly transport,which explains about 48%of CA precipitation.The remaining 10%of CA precipitation is explained by northerly transport,which steadily impacts north CA and causes a maximum in precipitation in the warm season.Most CA areas are exposed to seasonally varying moisture transport,except for southeast and north CA,which are impacted by southerly and northerly transport year-round.In general,the midlatitude westerlies-driven transport and the Indian monsoon-driven southerly-related transport explain most of the spatial differences in precipitation seasonality over CA.Moreover,the contribution ratio of local evaporation in CA to precipitation exhibits significant interdecadal variability and a meridionally oriented tripole of moisture transport anomalies.Since the early 2000s,CA has experienced a decade of anomalously low local moisture contribution,which seems jointly determined by the weakened moisture contribution from midlatitudes(the Atlantic,Europe,and CA itself)and the enhanced contribution from high latitudes(West Siberia and the Arctic)and tropical areas(South Asia and the Indian Ocean).

关键词： Central Asia precipitation seasonality recycling ratio moisture transport dynamical recycling model interdecadal variability

Leader trajectory planning method considering constraints of formation controller

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Journal of Systems Engineering and Electronics 2023年第5期34卷 1294-1308页

作者： yao Dongdong WANG Xiaofang lin Hai WANG Zhuping School of Aerospace Engineering Beijing Institute of TechnologyBeijing100081China Xi’an Institute of Electromechanical Information Technology Xi’an710065China

To ensure safe flight of multiple fixed-wing unmanned aerial vehicles(UAVs)formation,considering trajectory planning and formation control together,a leader trajectory planning method based on the sparse A*algorithm is introduced.Firstly,a formation controller based on prescribed performance theory is designed to control the transient and steady formation configuration,as well as the formation forming time,which not only can form the designated formation configuration but also can guarantee collision avoidance and terrain avoidance theoretically.Next,considering the constraints caused by formation controller on trajectory planning such as the safe distance,turn angle and step length,as well as the constraint of formation shape,a leader trajectory planning method based on sparse A^(*)algorithm is proposed.Simulation results show that the UAV formation can arrive at the destination safely with a short trajectory no matter keeping the formation or encountering formation transformation.

关键词： trajectory planning formation control prescribed performance controller multiple constraints formation shape formation transformation

Regulating the self-assembly of rigid 2D ribbon-like amphiphilic homopolymer via tailoring its holistic conformation

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Science China Chemistry 2023年第8期66卷 2339-2346页

作者： Yumeng Gao Weisheng Feng yao Sun Yuan yao Liquan Wang Shaoliang lin Shanghai Key Laboratory of Advanced Polymeric Materials Frontiers Science Center for Materiobiology and Dynamic Chemistry of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237China

Amphiphilic rigid backbone polymers are traditionally seemed as one-dimensional(1D)rods and show distinct self-assembly behavior to flexible polymers,but they could hardly adapt morphology-tunable self-assembly by changing their holistic conformation upon external stimuli.In this study,we synthesized a series of amphiphilic homopolymers poly(acetylene azobenzene oligoethylene glycol)(P(AAzo-EGx))containing conjugated polyacetylene mainchain,azobenzene pendants and oligo ethylene glycol tails in each unit.This comb-like amphiphilic polymer could be treated as two-dimensional(2D)nanoribbons with tunable holistic conformation via meticulous tailoring intrastrand repulsion and interchainπ-πinteraction of azobenzene pendants by light,temperature,and solvent swelling.P(AAzo-EG_(2))could self-assemble into large vesicles in ambient,whereas transformed to supramolecular helix bundles(SHBs)at 65℃as well as depicted by dissipative particle dynamics(DPD)simulation,and then turned into grass leaf-like micelles upon sequential ultraviolet(UV)and blue light irradiation.The three assemblies featured different stacking mode of PAAzo skeletons although showed similar aggregate induce emission(AIE)effect.In this holistic macromolecular chain conformation-induced self-assembly and morphology transformation,temperature influenced the stacking of hydrophobic parts mainly by tuning the torsion of PAAzo skeleton.Certain amount of good solvent played a vital role by swelling of hydrophobic PAAzo skeleton,and helping the movement and rearrangement of azobenzene pendants and polyacetylene mainchains like a lubricant.The length and diameter of SHBs could be tuned by changing EGxtails.This work uncovered a facile strategy to tailor the self-assembly of rigid backbone polymers for fabrication of functional nanodevices.

关键词： self-assembly tunable conformation rigid skeleton two-dimensional nanoribbon stimuli response

Dynamic State Estimation for Integrated Electricity-gas Systems Based on Kalman Filter

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CSEE Journal of Power and Energy Systems 2022年第1期8卷 293-303页

作者： Yanbo Chen Yuan yao Yuzhang lin Xiaonan Yang State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of Electrical&Electronic EngineeringNorth China Electric Power University102206 BeijingChina Qinghai Key Laboratory of Efficient Utilization of Clean Energy Tus-Institute for Renewable EnergyQinghai UniversityXining 810016China School of Engineering Xining UniversityXining 810016China School of Electrical&Electronic Engineering North China Electric Power University102206 BeijingChina Department of Electrical and Computer Engineering University of MassachusettsLowellMA 01852USA State Key Laboratory of Power Grid Safety and Energy Conservation China Electric Power Research Institute100192 BeijingChina

In recent years, integrated electricity-gas systems(IEGSs) have attracted widespread attention. The unifiedscheduling and control of the IEGS depends on high-precisionoperating data. To this end, it is necessary to establish anappropriate state estimation (SE) model for IEGS to filter theraw measured data. Considering that power systems and naturalgas systems have different time scales and sampling periods, thispaper proposes a dynamic state estimation (DSE) method basedon a Kalman filter that can consider the dynamic characteristicsof natural gas pipelines. First, the standardized state transitionequations for the gas system are developed by applying the finitedifference method to the partial differential equations (PDEs) ofthe gas system;then the DSE model for IEGS is formulatedbased on a Kalman filter;also, the measurements from theelectricity system and the gas system with different samplingperiods are fused to ensure the observability of DSE by using theinterpolation method. The IEEE 39-bus electricity system and the18-nodes Belgium gas system are integrated as the test systems.Simulation results verify the proposed method’s accuracy andcalculation efficiency.

关键词： Dynamic state estimation integrated electricitygas system Kalman filter two time-scale measurements transition state equation

A Survey on Pre-Processing in Image Matting

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Journal of Computer Science & Technology 2017年第1期32卷 122-138页

作者： Gui-Lin Yao School of Computer and Information Engineering Harbin University of Commerce Harbin 150028 China

Pre-processing is an important step in digital image matting, which aims to classify more accurate foreground and background pixels from the unknown region of the input three-region mask （Trimap）. This step has no relation with the well-known matting equation and only compares color differences between the current unknown pixel and those known pixels. These newly classified pure pixels are then fed to the matting process as samples to improve the quality of the final matte. However, in the research field of image matting, the importance of pre-processing step is still blurry. Moreover, there are no corresponding review articles for this step, and the quantitative comparison of Trimap and alpha mattes after this step still remains unsolved. In this paper, the necessity and the importance of pre-processing step in image matting are firstly discussed in details. Next, current pre-processing methods are introduced by using the following two categories： static thresholding methods and dynamic thresholding methods. Analyses and experimental results show that static thresholding methods, especially the most popular iterative method, can make accurate pixel classifications in those general Trimaps with relatively fewer unknown pixels. However, in a much larger Trimap, there methods are limited by the conservative color and spatial thresholds. In contrast, dynamic thresholding methods can make much aggressive classifications on much difficult cases, but still strongly suffer from noises and false classifications. In addition, the sharp boundary detector is further discussed as a prior of pure pixels. Finally, summaries and a more effective approach are presented for pre-processing compared with the existing methods.

关键词： image matting pixel classification pre-processing Trimap expansion