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Research on the identification of the production origin of Angelica dahurica using LIBS technology combined with machine learning algorithms

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Optoelectronics Letters 2024年第3期20卷 171-176页

作者： sun jiaxing LI Honglian YAO Yuhang YAN Qiongyan DONG Fang College of Quality and Technology Supervising Hebei UniversityBaoding 071000China National and Local Joint Engineering Center of Measuring Instruments and Metrology Systems Baoding 071000China Key Laboratory of Energy Measurement and Safety Detection Technology in Hebei Province Baoding 071000China

The origin of Angelica dahurica medicinal herbs varies, and their pharmacological effects also differ. In order to achieve rapid and accurate identification of the origin of Angelica dahurica medicinal herbs, this study utilizes laser induced breakdown spectroscopy(LIBS) technology combined with machine learning algorithms to identify the original source of Angelica dahurica. Sliced samples of Angelica dahurica were taken from four regions: Hebei, Henan, Zhejiang, and Sichuan. The spectral data from the sliced samples were used as features, and different algorithms including support vector machine(SVM), back propagation(BP) neural network, genetic algorithm-back propagation(GA-BP) neural network, particle swarm optimization-back propagation(PSO-BP) neural network, convolutional neural network(CNN), and CNN-SVM were employed to classify the origin of Angelica dahurica samples.

关键词： neural origin network

Influence of tungsten particle size on microstructure and mechanical properties of high strength and tough tungsten particle-reinforced nickel-based composites by laser-direct energy deposition

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Journal of Materials Science & Technology 2024年第5期172卷 213-227页

作者： Wenji Song Dengzhi Wang Congwen Tang Pengfei sun jiaxing Yang Zhidong Xu Tao Lai Jianqiang Gong Qianwu Hu Xiaoyan Zeng Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430000China

Tungsten(W)particle-reinforced nickel(Ni)-based composites were fabricated via laser-direct energy de-position(L-DED).The influence of the W particle size on the microstructure and mechanical properties of the deposited samples was systematically studied.The results indicate that refining the W particle size could refine theγ-Ni grains and subgrains,thin the(Ni,Cr)_(4)W interface layer,and increase the disloca-tion density of the intergranular matrix,thus improving the tensile strength and elongation of the L-DED samples.As W particle size decreased from 75 to 150μm to 6.5-12μm,the tensile strength and elonga-tion of the deposited samples increased by 150 MPa and 2.9 times to 1347.6±15.7 MPa and 17.5±0.4%,respectively.Based on the properties of the interface(Ni,Cr)_(4)W,a load-transfer efficiency factor suitable for this composite was proposed and the load-transfer strengthening formula was optimized.A quanti-tative analysis of the strengthening mechanisms was established considering load-transfer strengthening,Hall-Petch strengthening,thermal-mismatch strengthening,and solid-solution strengthening.The calcu-lated contribution of each strengthening mechanism to the yield strength and theoretical calculations were in good agreement with the experimental data.The article breaks the bottleneck of poor plasticity of W particle-reinforced Ni-based composites prepared by L-DED and provides a theoretical basis for the construction design of W particle-reinforced Ni-based composites with excellent mechanical properties.

关键词： Laser-direct energy deposition(L-DED) Tungsten particle reinforcements Mechanical property Strengthening mechanism

Solution-processed D-A-π-A-D radicals for highly efficient photothermal conversion

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Aggregate

Aggregate 2024年第1期5卷 398-408页

作者： jiaxing Huang Zejun Wang Weiya Zhu Yuan Li Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhouP.R.China

Organic donor-acceptor semiconductors exhibit great potential in photothermal conversion.However,it is still challenging to achieve pure organic materials with broad absorption comparable with inorganic materials such as graphene.Herein,two D-AD type DPA-BT-O4 and NDI-TPA-O4 and three D-A-π-A-D type Th-O4,Th2-O4,and IDT-O4 were readily prepared via two high-yield steps and simple air oxidization.The stability can be attributed to their multiple resonance structures based on the aromatic nitric acid radical mechanism.Compared with the D-A-D radicals,the conjugation extension of the D-A-π-A-D radicals endows them with a narrowed band gap and broad absorption in powder.Interestingly,the IDT-O4 powder with aggregation-induced radical effect exhibits broad absorption between 300 and 2500 nm,which is comparable with graphene and other inorganic materials.Under irradiation of 0.9 W/cm^(2)(808 nm),the temperature of IDT-O4 powder rises to 250℃within 60 s.The water evaporation conversion efficiency of 94.38%and an evaporation rate of 1.365 kg/m^(2)h^(−1)under one sun illumination were achieved.IDT-O4 stands as one of the most efficient photothermal conversion materials among pure organic materials via a rational design strategy.

关键词： donor-acceptor near-infrared absorption open-shell radicals photothermal conversion seawater desalination

Magnetic Wakame-Based Biochar/Ni Composites with Enhanced Adsorption Performance for Diesel

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Journal of Renewable Materials 2022年第12期10卷 3147-3165页

作者： Hua Jing Shiyao Lu Lili Ji Shijie Li Baikang Zhu Jian Guo jiaxing sun Lu Cai Yaning Wang National Marine Facilities Aquaculture Engineering Technology Research Center Zhejiang Ocean UniversityZhoushan316022China College of Petrochemical Engineering and Environment Zhejiang Ocean UniversityZhejiang Ocean UniversityZhoushan316022China College of Food and Medical Zhejiang Ocean UniversityZhoushan316022China Institute of Ocean Higher Education Zhejiang Ocean UniversityZhoushan316022China

In this study,the magnetic wakame biochar/Ni composites were prepared with three activating reagents of H_(3)PO_(4),ZnCl_(2) and KOH by one-step pyrolysis activation,characterized by BET,SEM,TEM,FI-IR,XRD,Raman,and elemental analyzer,and their adsorption performance for diesel were also analyzed.The results showed that wakame biochar/Ni composites had larger specific surface area,abundant porous structure,and various reactive groups,rendering its enhancement of adsorption efficiency.The adsorption experiments indicated that the maximum adsorption capacities for diesel using WBPA 0.5,WBHZ 0.5 and WBPH 0.5 were 4.11,8.83,and 13.47 g/g,respectively.The Langmuir model was more suitable for the adsorption isotherms process,and the Pseudo-second-order model could better describe the adsorption kinetic experimental.And the magnetic wakame biochar/Ni composites presented good stability and recyclability.This study provides a novel pattern for the high-value utilization of wakame,having huge potential in the treatment of oily wastewater.

关键词： Wakeme magnetic biochar/Ni composites activating reagents diesel adsorption

Surfactant-Modified Hydrophobic Biochar Derived from Laver (Porphyra haitanensis) with Superior Removal Performance for Kitchen Oil

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Journal of Renewable Materials 2023年第8期11卷 3227-3243页

作者： jiaxing sun Lili Ji Qianrui He Ran Li Xiaoyue Xia Yaning Wang Yi Yang Lu Cai Jian Guo National Marine Facilities Aquaculture Engineering Technology Research Center Zhejiang Ocean UniversityZhoushan316022China College of Food and Medical Zhejiang Ocean UniversityZhoushan316022China Institute of Ocean Higher Education Zhejiang Ocean UniversityZhoushan316022China

In this study,a novel absorpent(MSAR600℃)with a hydrophobic surface and hierarchical porous structure for the removal of kitchen oil was facilely fabricated from the macroalgae,laver(Porphyra haitanensis)by incorpor-ating high-temperature carbonization and alkyl polyglucosides(APG)and rhamnolipid(RL)surfactants modiﬁ-cation.The characterization results showed MSAR600℃ possessed a louts-leaf-like papillae microstructure with high contact angle(137.5°),abundant porous structure with high speciﬁc surface area(23.4 m^(2)/g),and various oxygen-containing functional groups(-OH,C=O,C-O).Batch adsorption experiments were conducted to inves-tigate the effect of adsorption time,temperature,pH,and absorbent dose on kitchen oil adsorption performance.Then the practical application for the removal of kitchen oil using MSAR600℃ was also performed.The results showed that MSAR600℃ had a higher removal efﬁciency for kitchen oil(75.98%),compared with the commercial detergent(72.3%).This study demonstrates an example of fabricating a green tableware detergent for enhanced removal performance of kitchen oil.

关键词： Laver biochar surfactant modiﬁcation kitchen oil removal mechanism

Aerosol characterization in a city in central China plain and implications for emission control

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Journal of Environmental Sciences 2021年第6期33卷 242-252页

作者： Zhijie Li Lu Lei Yanpei Li Chun Chen Qingqing Wang Wei Zhou jiaxing sun Conghui Xie Yele sun State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China

Extensive studies on aerosol chemistry have been carried out in megacities in China,however,aerosol characterization in Central China Plain(CCP)is limited.Here we conducted real-time measurements of fine particle composition with a time-of-flight aerosol chemical speciation monitor in Kaifeng,Henan province in October 2019.Our results showed that nitrate and organics constituted the major fraction of non-refractory PM_(2.5)for the entire study,on average accounting for 34%and 33%,respectively.However,aerosol composition was substantially different among four periods due to different meteorological conditions and chemical processing.For instance,nitrate presented the lowest contribution during the first period due to evaporative loss associated with high temperature(T),and then rapidly increased during polluted periods as a function of relative humidity(RH).Positive matrix factorization analysis showed the dominance of secondary organic aerosol(SOA)in OA,and also the changes in OA composition under different T and RH levels.In addition,this study is unique with two periods of local emission controls.Back trajectory and coefficient of divergence analysis showed that air pollution in CCP was overall homogeneously distributed.As a result,the effectiveness of local emission controls in this region was strongly affected by meteorological conditions and regional transport.We found that one of the periods with emission control even showed the highest concentrations for the entire study.Our results point towards the limited effect of local emission controls in mitigating air pollution in CCP,and highlight the importance of joint emission controls under unfavorable meteorological conditions.

关键词： Central China plain Aerosol composition Sources Organic aerosol Emission control

Discretely-supported nanoimprint lithography for patterning the high-spatial-frequency stepped surface

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Nano Research 2021年第8期14卷 2606-2612页

作者： Chunhui Wang Yu Fan Jinyou Shao Zhengjie Yang jiaxing sun Hongmiao Tian Xiangming Li Micro-and Nano-technology Research Center State Key Laboratory for Manufacturing Systems Engineering Xi’an Jiaotong UniversityXi’an 710049China

Non-planar morphology is a common feature of devices applied in various physical fields,such as light or fluid,which pose a great challenge for surface nano-patterning to improve their performance.The present study proposes a discretely-supported nanoimprint.lithography(NIL)technique to fabricate nanostructures on the extremely non-planar surface,namely high-spatial-frequency stepped surface.The designed discretely imprinting template implanted a discretely-supported intermediate buffer layer made of sparse pillars arrays.This allowed the simultaneous generation of air-cushion-like buffer and reliable support to the thin structured layer in the template.The resulting low bending stiffness and distributed concentrated load of the template jointly overcome the contact difficulty with a stepped surface,and enable the template to encase the stepped protrusion as tight as possible.Based on the proposed discretely-supported NIL,nanostructures were fabricated on the luminous interface of light emitting diodes chips that covered with micrometer step electrodes pad.About 96%of the utilized indium tin oxide transparent current spreading layer surface on top of the light emitting diode(LED)chips was coated with nanoholes array,with an increase by more than 40%in the optical output power.The excellent ability of nanopatterning a non-planar substrate could potentially lead innovate design and development of high performance device based on discretely-supported NIL.

关键词： nanoimprint lithography non-planar surface discretely-supported template nanopatterning semiconductor light emitting devices

西柏坡时期中国共产党统一战线工作的特点和规律

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河北省社会主义学院学报 2024年第1期 33-39页

作者：孙嘉星石家庄市社会主义学院河北石家庄050200

西柏坡时期党的统一战线工作在统一战线百年历史进程中发挥了重要作用。在中国共产党夺取新民主主义革命伟大胜利的关键阶段,统一战线成为西柏坡时期全党工作的重要内容之一,党领导人民开展了彻底的土地改革、广泛的民主运动、灵活的政... 详细信息

西柏坡时期党的统一战线工作在统一战线百年历史进程中发挥了重要作用。在中国共产党夺取新民主主义革命伟大胜利的关键阶段,统一战线成为西柏坡时期全党工作的重要内容之一,党领导人民开展了彻底的土地改革、广泛的民主运动、灵活的政治攻势和积极筹备新政协等统一战线工作实践,其特点表现为统一战线的对象和范围更为广泛、策略运用趋于成熟、目标直接面向新中国。回望历史,我们能够从党的统一战线历史中把握坚持党的领导、找到共同目标、兼顾原则性和灵活性、建立有效机制等统一战线工作的规律,切实增强认识规律的能力、遵循规律的定力和运用规律的魄力,对当前统一战线工作的开展具有重要指导作用。

关键词：中国共产党统一战线工作西柏坡时期规律

Functionalization-Directed Stabilization of Hydrogen-Bonded Polymer Complex Fibers:Elasticity and Conductivity

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Advanced Fiber Materials 2019年第1期1卷 71-81页

作者： Jiefu Li jiaxing sun Di Wu Wentao Huang Meifang Zhu Elsa Reichmanis Shuguang Yang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Center for Advanced Low-Dimension MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai 201620China School of Chemical and Biomolecular Engineering Georgia TechAtlantaGA 30332-0100USA

Elastic,repairable and conductive fibers are desirable in the newly emerging field of soft electronic and wearable devices.Here,we design a multifunctional fiber by incorporation of different components to optimize its performance.The combination of the poly(acrylic acid)(PAA)and poly(ethylene oxide)(PEO)through hydrogen bonding endows the fiber with high elasticity and repairability.Polydopamine(PDA)significantly increases the stability of the fiber,thus the fiber will not dissolve in alkaline solutions and still keep the repairable ability.The fiber shows a reversible swelling-shrinking property as pH values go up and down.Further,the conductive component,carbon nanotube,is adsorbed at the swelling state and then is fastened with fiber shrinking.

关键词： Hydrogen bond Polymer complex fiber Self-healing Elastic Conductive