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Geometric phase-encoded stimuli-responsive cholesteric liquid crystals for visualizing real-time remote monitoring:humidity sensing as a proof of concept

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Light(Science & Applications) 2024年第2期13卷 283-293页

作者： Shi-Long Li Zhao-yi Chen Peng Chen Wei hu Chaohong huang Sen-Sen Li Xuejia hu Yan-qing Lu Lu-Jian Chen Department of Electronic Engineering School of Electronic Science and EngineeringXiamen University361005 XiamenChina College of Engineering and Applied Sciences Nanjing University210093 NanjingChina Fujian Key Laboratory of Ultrafast Laser Technology and Applications Xiamen University361005 XiamenChina

Liquid crystals are a vital component of modern photonics,and recent studies have demonstrated the exceptional sensing properties of stimuli-responsive cholesteric liquid ***,existing cholesteric liquid crystal-based sensors often rely on the naked eye perceptibility of structural color or the measurement of wavelength changes by spectrometric tools,which limits their practical ***,developing a platform that produces recognizable sensing signals is *** this study,we present a visual sensing platform based on geometric phase encoding of stimuli-responsive cholesteric liquid crystal polymers that generates real-time visual patterns,rather than frequency *** demonstrate this platform’s effectiveness,we used a humidity-responsive cholesteric liquid crystal polymer film encoded with a q-plate pattern,which revealed that humidity causes a shape change in the vortex beam reflected from the encoded cholesteric liquid crystal ***,we developed a prototype platform towards remote humidity monitoring benefiting from the high directionality and long-range transmission properties of laser beams carrying orbital angular *** approach provides a novel sensing platform for cholesteric liquid crystals-based sensors that offers promising practical *** ability to generate recognizable sensing signals through visual patterns offers a new level of practicality in the sensing field with stimuli-responsive cholesteric liquid *** platform might have significant implications for a broad readership and will be of interest to researchers working in the field of photonics and sensing technology.

关键词： humidity visual liquid

Warming intensified the effects of nitrogen addition on N_(2)O emissions from alpine meadow in the northern qinghai-Tibet Plateau

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Advances in Climate Change Research 2024年第1期15卷 101-112页

作者： Ming-Jie LI yi-qing GE Hasbagan GANJURJAV Guo-Zheng hu Hong-Bao WU Jun YAN Shi-Cheng HE qing-Zhu GAO Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China National Agricultural Experimental Station for Agricultural Environment Nagqu 852100China Ecology and Nature Conservation Institute Chinese Academy of ForestryBeijing 100091China College of Resource and Environment Anhui Science and Technology UniversityFengyang 233100China Nagqu Agriculture Animal Husbandryand Prataculture Science and Technology Research and Extension CenterNagqu 852100China Tongliao Experimental Middle School Tongliao 028000China

Warming and nitrogen(N)addition may impact soil nitrous oxide(N_(2)O)emissions,but the relationship between plant community composition and soil microbial activities remains *** a two-year field study in the qinghai-Tibet Plateau,open-top chambers were used to quantify the effects of warming,N-addition,and their interactions on N_(2)O *** found that the N-addition greatly increased N_(2)O emissions by 77.4%in 2018 when compared to the control *** contrast,warming showed little effect on N_(2)0 emissions but did increase the activity of enzymes associated with soil nitrification and denitrification.A combined effect of warming and N-addition of resulted in 208.6%(2018)and 90.8%(2019)increase in N_(2)0 emissions,respectively,compared to the individual treatments of warming or *** warming in alpine meadows is causally linked to increased legume biomass which is further intensified with the *** legume biomass(p<0.05),soil moisture(p<0.001)and enzyme activity(p<0.001)had a positive effect on N_(2)0 emissions,while diminished microbial carbon/nitrogen(MBC/MBN)(p<0.05)correlated with reduced N_(2)O *** results indicated that N-addition has a positive effect on N_(2)O emissions,and the addition of warming further intensifies this *** increased dominance of legumes and microbial N content contributes to this *** outcomes suggest that warming and atmospheric N deposition can stimulate N_(2)O emissions of alpine meadows inthefuture.

关键词： Alpine meadow Community composition Nitrogen addition Nitrous oxide flux qinghai-Tibet Plateau Warming

Machine learning for carbonate formation drilling: Mud loss prediction using seismic attributes and mud loss records

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Petroleum Science 2024年第2期21卷 1241-1256页

作者： hui-Wen Pang Han-qing Wang yi-Tian Xiao Yan Jin Yun-hu Lu Yong-Dong Fan Zhen Nie National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China College of Science China University of Petroleum-BeijingBeijing102249China Petroleum Exploration and Production Research Institute SINOPECBeijing102206China College of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China Research Institute of Petroleum Exploration and Development CNPCBeijing100083China

Due to the complexity and variability of carbonate formation leakage zones, lost circulation prediction and control is one of the major challenges of carbonate drilling. It raises well-control risks and production expenses. This research utilizes the H oilfield as an example, employs seismic features to analyze mud loss prediction, and produces a complete set of pre-drilling mud loss prediction solutions. Firstly, 16seismic attributes are calculated based on the post-stack seismic data, and the mud loss rate per unit footage is specified. The sample set is constructed by extracting each attribute from the seismic trace surrounding 15 typical wells, with a ratio of 8:2 between the training set and the test set. With the calibration results for mud loss rate per unit footage, the nonlinear mapping relationship between seismic attributes and mud loss rate per unit size is established using the mixed density network ***, the influence of the number of sub-Gausses and the uncertainty coefficient on the model's prediction is evaluated. Finally, the model is used in conjunction with downhole drilling conditions to assess the risk of mud loss in various layers and along the wellbore trajectory. The study demonstrates that the mean relative errors of the model for training data and test data are 6.9% and 7.5%, respectively, and that R2is 90% and 88%, respectively, for training data and test data. The accuracy and efficacy of mud loss prediction may be greatly enhanced by combining 16 seismic attributes with the mud loss rate per unit footage and applying machine learning methods. The mud loss prediction model based on the MDN model can not only predict the mud loss rate but also objectively evaluate the prediction based on the quality of the data and the model.

关键词： Lost circulation Risk prediction Machine learning Seismic attributes Mud loss records

The New Methods for Characterization of Molecular Weight of Supramolecular Polymers

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Chinese Journal of Polymer Science 2024年第10期42卷 1403-1413页

作者： hui Liu Rui hu Zi-qing hu Xiao-Fan Ji Key Laboratory of Materials Chemistry for Energy Conversion and Storage Ministry of Education Hubei Key Laboratory of Materials Chemistry and Service FailureHubei Engineering Research Center for Biomaterials and Medical Protective Materials School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Supramolecular polymers, as a type of dynamic polymers, are subordinate to the interdisciplinary field of polymer chemistry and supramolecular chemistry, whose development has greatly promoted the prosperity of new materials. Notably, molecular weight is one of the most important parameters of supramolecular polymers, which affects the physical/chemical properties and processing applications of *** new methods for characterizing the molecular weight of supramolecular polymers is crucial for advancing the development of supramolecular polymers. In this review, we elaborate and summarize three strategies for characterizing the molecular weight of supramolecular polymers that recently reported by our research group according to the characteristics of supramolecular polymers, including (1) the molecular weight distinction corresponding to variable fluorescence colors,(2) matching different molecular weights with different fluorescence lifetime,(3) transforming supramolecular polymers into mechanically interlocked polymers or covalent polymers. Besides, we also discuss the limitations of current methods for characterizing supramolecular polymers. We hope that this review can promote the development of supramolecular polymers and significantly inspire to exploit new methods to characterizing molecular weight of supramolecular polymers.

关键词： Dynamic polymers Mechanically interlocked polymers Molecular weight Self-assembly Supramolecular polymers

Effect of the yaw angle on turbulent flow structures around the submarine model

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Journal of Hydrodynamics 2024年第3期36卷 421-434页

作者： yi-jing hu yi Qu Qin Wu Biao huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China Beijing Institute of Electronic System Engineering Beijing100854China

The objective of this paper is to investigate the turbulent flow structures around the submarine model and evaluate the effect of the yaw angle on the turbulent flow *** large eddy simulation based on the boundary data immersion method is used to *** computational domain consists of 1.2×10^(8)uniformly distributed Cartesian orthogonal grid nodes to capture the basic flow characteristics around the *** pressure coefficient,friction coefficient and wake velocity distribution are in good agreement with the experimental *** different types of vortex structures were mainly captured around the model,including horseshoe vortex,sail tip vortex and crossflow separation *** the increase of the yaw angle,the asymmetry of the horseshoe vortex and the tip vortex gradually increases,and the vortex strength of the vortex leg on the windward of the horseshoe vortex and the vortex strength of the tip vortex also increase *** the crossflow separation vortex,the flow separation zone gradually expands and migrates downstream with the increase of the yaw angle.

关键词： Vortex structure submarine model boundary data immersion method yaw angle

Outlier-resistant distributed fusion filtering for nonlinear discrete-time singular systems under a dynamic event-triggered scheme

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 237-249页

作者： Zhibin hu Jun hu Cai CHEN Hongjian LIU Xiaojian yi Department of Applied Mathematics Harbin University of Science and TechnologyHarbin150080China Heilongjiang Provincial Key Laboratory of Optimization Control and Intelligent Analysis for Complex Systems Harbin University of Science and TechnologyHarbin150080China School of Automation Harbin University of Science and TechnologyHarbin150080China School of Mathematics and Physics Anhui Polytechnic UniversityWuhu241000China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing100081China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing314003China Tangshan Research Institute Beijing Institute of TechnologyTangshan063099China

This paper investigates the problem of outlier-resistant distributed fusion filtering(DFF)for a class of multi-sensor nonlinear singular systems(MSNSSs)under a dynamic event-triggered scheme(DETS).To relieve the effect of measurement outliers in data transmission,a self-adaptive saturation function is ***,to further reduce the energy consumption of each sensor node and improve the efficiency of resource utilization,a DETS is adopted to regulate the frequency of data *** the addressed MSNSSs,our purpose is to construct the local outlier-resistant filter under the effects of the measurement outliers and the DETS;the local upper bound(UB)on the filtering error covariance(FEC)is derived by solving the difference equations and minimized by designing proper filter ***,according to the local filters and their UBs,a DFF algorithm is presented in terms of the inverse covariance intersection fusion *** such,the proposed DFF algorithm has the advantages of reducing the frequency of data transmission and the impact of measurement outliers,thereby improving the estimation ***,the uniform boundedness of the filtering error is discussed and a corresponding sufficient condition is ***,the validity of the developed algorithm is checked using a simulation example.

关键词： Distributed fusion filtering Multi-sensor nonlinear singular systems Dynamic event-triggered scheme Outlier-resistant filter Uniform boundedness

Land use effects on the dynamics of soil C,N and microbes in the water-wind erosion crisscross region of the northern Loess Plateau,China

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Pedosphere 2024年第1期34卷 181-190页

作者： yi WANG Chunyue LI Shunjin hu State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China Department of Entomology&Plant Pathology North Carolina State UniversityRaleigh 27695USA

The water-wind erosion crisscross region of the northern Loess Plateau in China is under constant pressure from severe erosion due to its windy and dry climate and intensive human activities. Identifying sustainable land use patterns is key to maintaining ecosystem sustainability in the area. Our aim was to appraise the impacts of different land use regimes on the dynamics of soil total organic C(TOC), total N(TN), and microbes in a typical watershed in the northern Loess Plateau to identify suitable land use types that can maintain soil fertility and sustainability. A field experiment was performed in Liudaogou watershed in Shenmu City, Shaanxi Province, China, where the dynamics of soil TOC and TN, microbial biomass C and N, microbial respiration, and net N mineralization in six typical land use types, dam land, rainfed slope land, deciduous broadleaf forest, evergreen coniferous forest, shrubland, and grassland,were measured in three different growing seasons. Land use type and season significantly affected TOC, TN, and the dynamics of microbial biomass and activity. As the most anthropogenically disturbed land use pattern, dam land was an optimal land use pattern for TOC sequestration due to its higher TOC and TN, but lower microbial activity. Soil TOC, TN, and microbial properties demonstrated a decreasing trend after natural grassland was converted to shrubland,forest, and rainfed slope land. Shrubland with exotic N-fixing Korshinsk peashrub(Caragana korshinskii Kom.) can maintain TOC, TN, and microbial properties similar to those in grassland. Soil TOC, NH_(4+)^(-)N, TN, moisture, and extractable C were the principal indexes for soil microbial biomass and activity and explained 88.90% of the total variance. Thus, grassland was the optimal land use pattern in the water-wind erosion crisscross region of the northern Loess Plateau to maintain ecosystem stability and sustainability.

关键词： grassland microbial activity microbial biomass total organic C total N watershed

Effects of the urban landscape on heatwave-mortality associations in Hong Kong: comparison of different heatwave definitions

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Frontiers of Environmental Science & Engineering 2024年第1期18卷 145-156页

作者： Jinglu Song yi Lu Thomas Fischer Kejia hu Department of Urban Planning and Design Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China Department of Architecture and Civil Engineering City University of Hong KongKowloon TongHong Kong 999077China Environmental Assessment and Management Research Centre School of Environmental SciencesUniversity of LiverpoolLiverpool L35TRUK Research Unit for Environmental Sciences and Management Faculty of Natural and Agricultural SciencesNorth West UniversityPotchefstroom 31750South Africa Institute of Big Data in Health Science School of Public HealthZhejiang UniversityZijingang CampusHangzhou 310058China

Despite increased attention given to potential modifiers of temperature-mortality associations, evidence for variations between different urban landscape characteristics remains limited. It is in this context that in this paper effect modifications of multiple urban landscape characteristics are explored under different heatwave definitions for different age groups and gender in Hong Kong, China. Daily meteorological data and heatwave-related mortality counts from 2008 to 2017 were collected from the Hong Kong Census and Statistics Department, China. A case-only design was adopted, combined with logistic regression models to examine the modification effects of five urban landscape characteristics under six heatwave definitions. Stratified analyses were conducted to investigate age- and gender-specific effect modifications. It is found that individuals living in greener areas experienced lower levels of mortality during or immediately after heatwaves. In contrast, a higher building density and nighttime land surface temperature (LST) were associated with a higher heatwave-related mortality risk. Pronounced effect modifications of these urban landscape characteristics were observed under hotter and longer heatwaves, and in older adults (age ≥ 65 years) and males. The findings provide a scientific basis for policymakers and practitioners when considering measures for coping with hotter, longer, and more frequent heatwaves in the context of global climate change.

关键词： Urban landscape Heatwave Mortality Effect modification Intra-urban differences Health risk reduction

Activation of glutamatergic neurons in the somatosensory cortex promotes remyelination in ischemic vascular dementia

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Fundamental Research 2024年第1期4卷 188-198页

作者： yi-Ting Zhou Da-Dao An yi-Xin Xu ying Zhou qing-qing Li Hai-Bin Dai Xiang-Nan Zhang yi Wang Min Lou Zhong Chen Wei-Wei hu Department of Pharmacology and Department of Pharmacy of the Second Affiliated Hospital NHC and CAMS Key Laboratory of Medical NeurobiologySchool of Basic Medical SciencesCollege of Pharmaceutical SciencesZhejiang University School of MedicineHangzhou 310058China Department of Pharmacy Sir Run Run Shaw HospitalHangzhou 310012China Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical SciencesZhejiang Chinese Medical UniversityHangzhou 310053China Department of Neurology the Second Affiliated Hospital of Zhejiang UniversitySchool of MedicineHangzhou 310003China

Chronic cerebral hypoperfusion can cause progressive demyelination as well as ischemic vascular dementia,however no effective treatments are ***,based on magnetic resonance imaging studies of patients with white matter damage,we found that this damage is associated with disorganized cortical *** a mouse model,optogenetic activation of glutamatergic neurons in the somatosensory cortex significantly promoted oligodendrocyte progenitor cell(OPC)proliferation,remyelination in the corpus callosum,and recovery of cognitive ability after cerebral *** therapeutic effect of such stimulation was restricted to the upper layers of the cortex,but also spanned a wide time window after ***,enhancement of glutamatergic neuron-OPC functional synaptic connections is required to achieve the protection effect of activating cortical glutamatergic ***,skin stroking,an easier method to translate into clinical practice,activated the somatosensory cortex,thereby promoting OPC proliferation,remyelination and cognitive recovery following cerebral *** summary,we demonstrated that activating glutamatergic neurons in the somatosensory cortex promotes the proliferation of OPCs and remyelination to recover cognitive function after chronic cerebral *** should be noted that this activation may provide new approaches for treating ischemic vascular dementia via the precise regulation of glutamatergic neuron-OPC circuits.

关键词： Chronic cerebral hypoperfusion Optogenetic stimulation Oligodendrocyte progenitor cellIschemic vascular dementia Glutamatergic neuron Remyelination