多功能热电织物用于可穿戴无线传感系统

Flexible thermoelectric materials play an important role in smart wearables,such as wearable power generation,self-powered sensing,and personal thermal management.However,with the rapid development of Internet of Things(IoT)and artificial intelligence(AI),higher standards for comfort,multifunctionality,and sustainable operation of wearable electronics have been proposed,and it remains challenging to meet all the requirements of currently reported thermoelectric devices.Herein,we present a multifunctional,wearable,and wireless sensing system based on a thermoelectric knitted fabric with over 600 mm·s^(-1)air permeability and a stretchability of 120%.The device coupled with a wireless transmission system realizes self-powered monitoring of human respiration through an mobile phone application(APP).Furthermore,an integrated thermoelectric system was designed to combine photothermal conversion and passive radiative cooling,enabling the characteristics of being powered by solar-driven in-plane temperature differences and monitoring outdoor sunlight intensity through the APP.Additionally,we decoupled the complex signals of resistance and thermal voltage during deformation under solar irradiation based on the anisotropy of the knitted fabrics to enable the device to monitor and optimize the outdoor physical activity of the athlete via the APP.This novel thermoelectric fabricbased wearable and wireless sensing platform has promising applications in next-generation smart textiles.

Waste Cotton-Derived Fiber-Based Thermoelectric Aerogel for Wearable and Self-Powered Temperature-Compression Strain Dual-Parameter Sensing

The rapid development of the global economy and population growth are accompanied by the production of numerous waste textiles.This leads to a waste of limited resources and serious environmental pollution problems caused by improper disposal.The rational recycling of wasted textiles and their transformation into high-value-added emerging products,such as smart wearable devices,is fascinating.Here,we propose a novel roadmap for turning waste cotton fabrics into three-dimensional elastic fiber-based thermoelectric aerogels by a one-step lyophilization process with decoupled self-powered temperature-compression strain dual-parameter sensing properties.The thermoelectric aerogel exhibits a fast compression response time of 0.2 s,a relatively high Seebeck coefficient of 43μV·K^(-1),and an ultralow thermal conductivity of less than 0.04 W·m^(-1)·K^(-1).The cross-linking of trimethoxy(methyl)silane(MTMS)and cellulose endowed the aerogel with excellent elasticity,allowing it to be used as a compressive strain sensor for guessing games and facial expression recognition.In addition,based on the thermoelectric effect,the aerogel can perform temperature detection and differentiation in self-powered mode with the output thermal voltage as the stimulus signal.Furthermore,the wearable system,prepared by connecting the aerogel-prepared array device with a wireless transmission module,allows for temperature alerts in a mobile phone application without signal interference due to the compressive strains generated during gripping.Hence,our strategy is significant for reducing global environmental pollution and provides a revelatory path for transforming waste textiles into high-value-added smart wearable devices.

LLSDA: Design and Implementation of Lightning Location Data Analysis and Visualization

Visualizing lightning location data is necessary in analyzing and researching lightning activity patterns.This article uses C#and the cross-platform.NET framework to develop a lightning location data analysis class library and the data-driven client to help lightning researchers improve work efficiency by avoiding repeated wheel invention.Lightning Location System Data Analyzer(LLSDA)is a suite of software tools that includes a.NET class library for software developers and a desktop application for end users.It supports a wide range of lightning location data formats,such as the University of Washington Global Lightning Location System(WWLLN)and Beijing Huayun Dongfang ADTD Lightning Location System data format,and maintains scalability.The class library can easily read,parse,and analyze lightning location data,and combined with third-party frameworks can realize grid analysis.The desktop application can be combined with MeteoInfo(a GIS open-source project)for secondary development.

Research on the New Model of Student Education Management in Vocational Colleges

Vocational colleges are an important type of higher education in China.Higher vocational education aims to adapt to social needs and designs students’knowledge,ability,quality structure,and training plans based on the cultivation of technical application skills.Emphasizing both theoretical teaching and practical training,graduates have the skills to work directly.At this stage,vocational education in China is in an important period of transformation and development.In order to better adapt to the rapid development of society,many vocational colleges have carried out management system reforms in student education management,with the aim of cultivating more high-quality and skilled talents that meet the needs of social development,and providing higher quality vocational education services for the country and society.In the process of physical education reform,due to regional and other factors,many reform models cannot adapt to the current situation of student education management in vocational colleges in the new era.Therefore,it is necessary to continuously explore new models suitable for vocational colleges.Based on the background of the physical education reform in vocational colleges,this article uses methods such as literature research and visits to analyze the current situation of education management in vocational colleges,the problems and possible reasons that exist in student education management in vocational colleges.This article discusses the possible new models of student education management in vocational colleges from the perspectives of repeated management methods,management concepts,management mechanisms,and evaluation systems,and elaborates on their new paths.Efforts are made to improve the management mode of student education in vocational colleges,innovate the management mechanism of vocational colleges,and actively explore the improvement of the management mode of student education in vocational colleges.

A Comparative Study on That Design of Agricultural Canal in Ecological and Traditional Renovation of Agricultural Land—Take a Project Area in Lingchuan County, Guilin City, Guangxi, China as an Example

In the current context of vigorously promoting the construction of ecological civilization, land consolidation in the construction of the constant pursuit of ecological design, to achieve sustainable use of land resources, China has made great progress in ecological land consolidation. In this paper, through the comparison of flow design and cross section design of agricultural canal design in ecological land remediation and traditional land remediation, the characteristic design of some agricultural canals in ecological land remediation was introduced, and the ecological, social and economic benefits of two land remediation methods were systematically analyzed. The analysis shows that ecological agricultural canals play a great role in protecting biodiversity, alleviating the contradiction between people and land, saving energy, purifying water resources and improving land quality, the research result has provided the basis and the model for the land consolidation in carrying on the ecology type ditch design.

Dividing the Expropriated Areas Based on Multi-Factor Comprehensive Evaluation—A Case Study of Gongcheng Yao Autonomous County

In recent years, with the rapid development of urbanization in China, land acquisition work is particularly important. The division of expropriated area is the primary factor to be considered when evaluating the comprehensive land price of expropriated area. Reasonable division can help to improve the scientific and applicability of the comprehensive land price of the region. How to maximize the protection of farmers’ rights and interests by the division of land requisition is an urgent problem to be solved. Taking Gongcheng Yao Autonomous County as an example, this study adopted the multi-factor comprehensive evaluation method to evaluate the division of land requisition in this area, and carried out the corresponding spatial analysis and data processing based on GIS technology. Gongcheng Yao Autonomous County was divided into levy areas, and the Delphi method was used to screen the impact factors and determine the weight of the levy areas. Reasonable division of land requisition area can provide references for land requisition area, make it more scientific and reasonable, and protect the rights and interests of farmers.

Potential Analysis of Inefficient Garden Land and Residual Forest Land Remediation in Comprehensive Land Remediation of the Whole Region—A Case Study of Zhemu Town, Guilin City, China

The remediation of inefficient garden land and defective forest land is one of the important sources and types of supplementary cultivated land in the comprehensive land remediation of the whole region. The remediation and development of inefficient garden land and defective forest land will effectively alleviate the multiple pressures faced by cultivated land at present. Taking Zhemu Town, Guilin City, China as an example, on that basis of the data of the third national land survey, using analytic hierarchy process, this paper selects six evaluation factors, including water source, traffic, slope, field concentration, farmland infrastructure and villagers’ will, to study the remediation potential of inefficient garden land and defective forest land in Zhemu Town, and delimits four potential divisions, in order to provide the basis for the arrangement of land remediation projects in Zhemu Town. The results show that the northern, central and western regions of Zhemu Town have great remediation potential.

Propagation of positive, negative, and recoil leaders in upward lightning flashes

Leader propagation is a fundamental issue in lightning physics. The propagation characteristics of positive leaders and negative leaders are summarized and compared based on data from high-speed camera and electromagnetic field in rocket-triggered lightning and tower-initiated lightning discharges; available channel base current data recorded in rocket-triggered lightning are also used. The negative leaders propagate in a stepped fashion accompanied by many branches. The stems ahead of the negative leader tip determine the manner and direction of the leader propagation, and even the branching and winding of the lightning channel. The impulsive current, electromagnetic field, and related optical images suggest that the positive leader may develop in a step-like fashion at its initial stage of triggered lightning. However, the stepping processes of the positive leader are obviously different from those of the negative leader. Tower-initiated lightning revealed that the most conspicuous characteristics of the stepwise positive leader involve the intermittent brush-like corona zone in front of the leader tip and the luminosity enhancement of the channel behind the tip. In rockettriggered lightning flashes, the charge transferred during an individual step for the negative leader was nearly an order greater than for the positive counterpart. The successive streamers ahead of the leader tip are essential for both negative and positive leader propagation, and the stems could be formed from one or more streamers in the previous negative streamer zone with the main leader channel dim. High-resolution observation of tower lightning also revealed a new type of bidirectional recoil leader, with polarity contrary to the traditional one, traversing in negative channels associated with tower-initiated and rocket-triggered lightning.

Update of Cultivated Land Quality Grade Based on GIS—A Case Study of a County in Guangxi

The quality of cultivated land has an important influence on agricultural output, food security, sustainable development and the ability of using cultivated land resources. As the trend of cultivated land quality is getting more and more attention, in order to strengthen the management of cultivated land quality, improve the precision of cultivated land quality and other achievements, and maintain the current situation of cultivated land quality and other achievements. For this paper, taking A county of Guangxi Zhuang Autonomous Region as an example, with the support of GIS, the paper studies the grade and grade renewal of cultivated land by using the superposition method, studies the grade and grade change of regional cultivated land and its spatial distribution, grasps the status quo change of cultivated land and the grade and grade change of cultivated land caused by the quality construction of cultivated land in the year, and then provides scientific data for land use plan, land consolidation and cultivates land protection.

A Calculation Method of Rolling Characteristics of Canard Missile with Free-Spinning Tails

The steady flow field of a canard missile on different angles of attack and Mach numbers were studied. Based on analysis, a method was proposed to reduce the calculation for the rolling characteristics of the canard missile with free-spinning tails, and was tested to obtain the relations between rolling moment coefficient, Mach number, and angle of attack. All the computed rolling moment coefficients obtained from the proposed method greatly agreed with the experimental results of FD-06 wind tunnel in CAAA, which proved that the method can not only reduce the calculation cost but also keep precision in calculating the rolling characteristics of canard missiles.

Distributed Asynchronous Learning for Multipath Data Transmission Based on P-DDQN

Adaptive packet scheduling can efficiently enhance the performance of multipath Data Transmission.However,realizing precise packet scheduling is challenging due to the nature of high dynamics and unpredictability of network link states.To this end,this paper proposes a distributed asynchronous deep reinforcement learning framework to intensify the dynamics and prediction of adaptive packet scheduling.Our framework contains two parts:local asynchronous packet scheduling and distributed cooperative control center.In local asynchronous packet scheduling,an asynchronous prioritized replay double deep Q-learning packets scheduling algorithm is proposed for dynamic adaptive packet scheduling learning,which makes a combination of prioritized replay double deep Q-learning network(P-DDQN)to make the fitting analysis.In distributed cooperative control center,a distributed scheduling learning and neural fitting acceleration algorithm to adaptively update neural network parameters of P-DDQN for more precise packet scheduling.Experimental results show that our solution has a better performance than Random weight algorithm and Round-Robin algorithm in throughput and loss ratio.Further,our solution has 1.32 times and 1.54 times better than Random weight algorithm and Round-Robin algorithm on the stability of multipath data transmission,respectively.

Deep white matter hyperintensity is spatially correlated to MRI-visible perivascular spaces in cerebral small vessel disease on 7 Tesla MRI

Background The association between perivascular space(PVS)and white matter hyperintensity(WMH)has been unclear.Normal-appearing white matter(NAWM)around WMH is also found correlated with the development of focal WMH.This study aims to investigate the topological connections among PVS,deep WMH(dWMH)and NAWM around WMH using 7 Tesla(7T)MRI.Methods Thirty-two patients with non-confluent WMHs and 16 subjects without WMHs were recruited from our department and clinic.We compared the PVS burden between patients with and without WMHs using a 5-point scale.Then,the dilatation and the number of PVS within a radius of 1 cm around each dWMH were compared with those of a reference site(without WMH)in the contralateral hemisphere.In this study,we define NAWM as an area within the radius of 1 cm around each dWMH.Furthermore,we assessed the spatial relationship between dWMH and PVS.Results Higher PVS scores in the centrum semiovale were found in patients with>5 dWMHs(median 3)than subjects without dWMH(median 2,p=0.014).We found there was a greater dilatation and a higher number of PVS in NAWM around dWMH than at the reference sites(p<0.001,p<0.001).In addition,79.59%of the dWMHs were spatially connected with PVS.Conclusion dWMH,NAWM surrounding WMH and MRI-visible PVS are spatially correlated in the early stage of cerebral small vessel disease.Future study of WMH and NAWM should not overlook MRI-visible PVS.

Measurement of atmospheric nanoparticles:Bridging the gap between gas-phase molecules and larger particles

Atmospheric nanoparticles are crucial components contributing to fine particulate matter(PM_(2.5)),and therefore have significant effects on visibility,climate,and human health.Due to the unique role of atmospheric nanoparticles during the evolution process from gas-phase molecules to larger particles,a number of sophisticated experimental techniques have been developed and employed for online monitoring and characterization of the physical and chemical properties of atmospheric nanoparticles,helping us to better understand the formation and growth of new particles.In this paper,we firstly review these state-of-the-art techniques for investigating the formation and growth of atmospheric nanoparticles(e.g.,the gas-phase precursor species,molecular clusters,physicochemical properties,and chemical composition).Secondly,we present findings from recent field studies on the formation and growth of atmospheric nanoparticles,utilizing several advanced techniques.Further-more,perspectives are proposed for technique development and improvements in measuring atmospheric nanoparticles.

Photocatalytic Metal-Free Radical Hydrosilylation for Polymer Functionalization

Comprehensive Summary,Post-modification of polymers offers a route to prepare functionalized polymers through efficient chemical reactions,and hydrosilylation is one of the most effective strategies.Silane-functionalized polymers have found a wide range of potential applications,such as adhesives,rubbers,and drug delivery agents.For decades,the hydrosilylation for the post-modification of polymers has typically used transition metals as catalysts.Metal-free hydrosilylation strategies that can avoid metal residues in polymers are largely lacking in this field.Herein,we report the photocatalytic metal-free radical hydrosilylation strategy for the post-modification of polymers bearing pendant vinyl groups using the organic photocatalyst and hydrogen atom transfer(HAT)catalyst under blue light irradiation.We used monofunctional silanes to functionalize polymers and the bis(silane)s as crosslinkers to prepare crosslinked polymers.

Light absorption properties and potential sources of brown carbon in Fenwei Plain during winter 2018–2019

A distinctive kind of organic carbon aerosol that could absorb ultraviolet-visible radiation is called brown carbon(Br C),which has an important positive influence on radiative budget and climate change.In this work,we reported the absorption properties and potential source of Br C based on a seven-wavelength aethalometer in the winter of 2018–2019 at an urban site of Sanmenxia in Fenwei Plain in central China.Specifically,the mean value of Br C absorption coefficient was 59.6±36.0 Mm^(-1) at 370 nm and contributed 37.7%to total absorption,which made a significant impact on visibility and regional environment.Absorption coefficients of Br C showed double-peak pattern,and Br C had shown small fluctuations under haze days compared with clean days.As for the sources of Br C,Br C absorption coefficients expressed strong correlations with element carbon aerosols and primary organic carbon aerosols,indicating that most of Br C originated from primary emissions.The linear correlations between trace metal elements(K,As,Fe,Mn,Zn,and Pb)and Br C absorption coefficients further referred that the major sources of Br C were primary emissions,like coal burning,biomass burning,and vehicle emissions.The moderate relationship between Br C absorption coefficients and secondary organic aerosols suggested that secondary production of Br C also played an important role.The 120 hr backward air mass trajectories analysis and concentration-weighted trajectories analysis were also used to investigate potential sources of Br C in and around this area,which inferred most parts of Br C were derived from local emissions.

Evaluation and impact factors of indoor and outdoor gas-phase nitrous acid under different environmental conditions

As an important indoor pollutant,nitrous acid(HONO) can contribute to the concentration of indoor OH radicals by photolysis via sunlight penetrating into indoor environments,thus affecting the indoor oxidizing capability.In order to investigate the concentration of indoor HONO and its impact factors,three different indoor environments and two different locations in urban and suburban areas were selected to monitor indoor and outdoor pollutants simultaneously,including HONO,NO,NO2,nitrogen oxides(NOx),O3,and particle mass concentration.In general,the concentration of indoor HONO was higher than that outdoors.In the urban area,indoor HONO with high average concentration(7.10 ppbV) was well-correlated with the temperature.In the suburban area,the concentration of indoor HONO was only about 1-2 ppbV,and had a good correlation with indoor relative humidity.It was mainly attributed to the heterogeneous reaction of NO2 on indoor surfaces.The sunlight penetrating into indoor environments from outside had a great influence on the concentration of indoor HONO,leading to a concentration of indoor HONO close to that outdoors.

Understanding the dynamical-microphysical-electrical processes associated with severe thunderstorms over the Beijing metropolitan region

The Dynamical-microphysical-electrical Processes in Severe Thunderstorms and Lightning Hazards(STORM973)project conducted coordinated comprehensive field observations of thunderstorms in the Beijing metropolitan region(BMR)during the warm season from 2014 to 2018.The aim of the project was to understand how dynamical,microphysical and electrical processes interact in severe thunderstorms in the BMR,and how to assimilate lightning data in numerical weather prediction models to improve severe thunderstorm forecasts.The platforms used in the field campaign included the Beijing Lightning Network(BLNET,consisting of 16 stations),2 X-band dual linear polarimetric Doppler radars,and 4 laser raindrop spectrometers.The collaboration also made use of the China Meteorological Administration’s mesoscale meteorological observation network in the Beijing-Tianjin-Hebei region.Although diverse thunderstorm types were documented,it was found that squall lines and multicell storms were the two major categories of severe thunderstorms with frequent lightning activity and extreme rainfall or unexpected local short-duration heavy rainfall resulting in inundations in the central urban area,influenced by the terrain and environmental conditions.The flash density maximums were found in eastern Changping District,central and eastern Shunyi District,and the central urban area of Beijing,suggesting that the urban heat island effect has a crucial role in the intensification of thunderstorms over Beijing.In addition,the flash rate associated with super thunderstorms can reach hundreds of flashes per minute in the central city regions.The super(5%of the total),strong(35%),and weak(60%)thunderstorms contributed about 37%,56%,and 7%to the total flashes in the BMR,respectively.Owing to the close connection between lightning activity and the thermodynamic and microphysical characteristics of the thunderstorms,the lightning flash rate can be used as an indicator of severe weather events,such as hail and short-duration heavy rainfall.Lightning data can also be assimilated into numerical weather prediction models to help improve the forecasting of severe convection and precipitation at the cloud-resolved scale,through adjusting or correcting the thermodynamic and microphysical parameters of the model.

Novel drug-delivery approaches to the blood-brain barrier

The blood-brain barrier （BBB） maintains homeostasis by blocking toxic molecules from the circulation, but drugs are blocked at the same time. When the dose is increased to enhance the drug concentration in the central nervous system, there are side-effects on peripheral organs. In recent years, genetic therapeutic agents and small molecules have been used in various strategies to penetrate the BBB while minimizing the damage to systemic organs. In this review, we describe several representative methods to circumvent or cross the BBB, including chemical and physical strategies.

Rapidly developable therapeutic-grade equine immunoglobulin against the SARS-CoV-2 infection in rhesus macaques

Dear Editor,The unprecedented COVID-19 pandemic caused by SARS-CoV-2 remains ongoing,but there is a lack of fully effective treatments.Convalescent plasma-derived hyperimmune globulins have been a safe and effective treatment but restricted by the difficulties in obtaining sufficient plasma with high antibody titers from a large number of recovered patients.Heterologous antibodies,particularly equine antibodies,have been widely used for decades as the therapeutics against some viral infections or as antivenoms.1 Equine antibodies could be rapidly developed and manufactured into therapeutic antibodies in large quantities under WHO standardized guidelines.Here we explored the development of equine antibody-derived F(ab′)2 as an option to treat COVID-19 by targeting the receptor-binding domain(RBD)of the viral spike protein that is essential for the viral entry into the host cells.2 We observed excellent neutralization titers of the F(ab′)2 in vitro and high potency against SARS-CoV-2 infection in the nonhuman primate rhesus macaques.

Chemical composition of different size ultrafine particulate matter measured by nanoparticle chemical ionization mass spectrometer

New particle formation(NPF)is the primary source of nanoparticles and contributes a large number of concentrations of cloud condensation nuclei.In recent years,field campaigns and laboratory experiments have been conducted to promote cognition of the mechanism for NPF and its following growth processes.The chemical composition measurement of nanoparticles could help deepen understanding of the initial step of particulate matter formation.In this work,we developed a nanoparticle chemical ionization mass spectrometer to measure nanoparticles’chemical compositions during their initial growth stage.Meanwhile,a non-radioactive ion source was designed for aerosol charging and chemical ionization.Time of flight mass spectrometer coupled with integrated aerosol size selection and collection module would guarantee the picogram level detection limit and high-resolution ability to measure the matrix of ambient samples.The performance of this equipment was overall evaluated,including the transmission efficiency and collection efficiency of custombuilt nano differential mobility analyzer,chemical ionization efficiency,and mass resolution of the mass spectrometer.The high sensitivity measurement of ammonium sulfate and methylammonium sulfate aerosols with diameters ranging from 10 to 25 nm could guarantee the application of this instrument in the ambient measurement.