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Luminescence and magnetic properties of bifunctional nanoparticles composited by nitrogen-doped graphene quantum dots and gadolinium

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Journal of Rare Earths 2024年第4期42卷 716-723页

作者： Wanli Zhang Hao Zhou Meigui Ou Donghao Sun chunlin yang College of Materials and Metallurgy University of GuizhouGuiyang550025China National Local Co-construction Engineering Laboratory for High Performance Metal Structure Material and Manufacture Technology Guiyang550025 China College of Chemistry and Materials Engineering Guiyang UniversityGuiyang550003China

In this paper,nitrogen-doped graphene quantum dots(N-GQDs)were combined with gadolinium ions(Gd^(3+))by a surface modification to obtain magneto-optical dual-functional N-GQDs/Gd^(3+)nanoparticles.The morphology of obtained composite was characterized by field emission scanning electron microscopy and transmission electron microscopy.Luminescence and magnetic properties were measured by a fluorescence spectrophotometer and a vibrating sample magnetometer,respectively.Results indicate that well-dispersed spherical N-GQDs/Gd^(3+)nanoparticles have an average diameter of 7 nm.N-doping significantly increases the luminesce nce of particles with an optimal luminescence intensity at 20℃and pH=9.X-ray photoelectron spectroscopy results indicate that the N-doping introduces pyrrolic N as an electron donor,enhancing fluorescence by increasing the surface electron cloud density of N-GQDs.In addition,density functional theory calculation results reveal that N-doping reduces the band gap of NGQDs/Gd^(3+),enabling electronic transitions to higher energy levels and generating more activation sites,thereby enhancing luminescence.Compared to N-GQDs/Gd^(3+)prepared at 20℃,the saturated magnetization of particles prepared at 40℃is 0.85 emu/g,indicating a better magnetic response.The above results suggest that bifunctional nanomaterials N-GQDs/Gd^(3+)with excellent optical properties and magnetism can be better used for fluorescence and magnetic resonance imaging.

关键词： Nitrogen-doped graphenequantum dots Gadolinium Luminescence Magnetism Rare earths

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Uncovering the electrooxidation behavior of 5-hydroxymethylfurfural on Ni/Co electrodes

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Journal of Energy Chemistry 2024年第5期92卷 1-7页

作者： Shilin Fan Bin Zhu Xiao Yu yang Gao Weiping Xie Yong yang Jian Zhang chunlin Chen Ningbo Institute of Materials Technology&Engineering Chinese Academy of SciencesNingbo 315201ZhejiangChina University of Chinese Academy of Sciences Beijing 100049China

Biomass,derived from plant photosynthesis that captures carbon dioxide to form carbohydrates,offers vast renewable reserves.The electrooxidation of biomass,coupled with the hydrogen evolution reaction,enables the simultaneous production of biomass-based plastic monomers and green hydrogen,attracting significant scholarly interest.However,ambiguity remains regarding the adsorption mechanism at the catalyst surface(Langmuir-Hinshelwood or Eley-Rideal)and the adsorbed substrate groups.To address this,we prepared a Ni/Co electrode for the electrooxidation of 5-hydroxymethylfurfural(HMF)into 2,5-furandicarboxylic acid(FDCA)through a corrosion reaction and electro-reduction pathway.HMF conversion reached 100.00%,FDCA yield reached 96.82%,and Faradic efficiency(FE)reached 92.14%.Meaningfully,utilizing in-situ spectroscopy and electrochemical methods,this work provided valuable insights into active sites and catalyst surface adsorption.

关键词： Electrocatalysis Electrochemistry 2,5-Furandicarboxylicacid 5-Hydroxymethylfurfural Biomass

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A functionalized activated carbon adsorbent prepared from waste amidoxime resin by modifying with H_(3)PO_(4) and ZnCl_(2) and its excellent Cr(Ⅵ)adsorption

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 585-598页

作者： chunlin He Yun Liu Mingwei Qi Zunzhang Liu Yuezhou Wei Toyohisa Fujita Guifang Wang Shaojian Ma Wenchao yang School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi UniversityNanning 530004China School of Nuclear Science and Technology University of South ChinaHengyang 421000China School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of New Low-carbon Green Chemical Technology Education Department of Guangxi Zhuang Autonomous RegionNanning 530004China

With the application of resins in various fields, numerous waste resins that are difficult to treat have been produced. The industrial wastewater containing Cr(Ⅵ) has severely polluted soil and groundwater environments, thereby endangering human health. Therefore, in this paper, a novel functionalized mesoporous adsorbent PPR-Z was synthesized from waste amidoxime resin for adsorbing Cr(Ⅵ). The waste amidoxime resin was first modified with H3PO4 and ZnCl_(2), and subsequently, it was carbonized through slow thermal decomposition. The static adsorption of PPR-Z conforms to the pseudo-second-order kinetic model and Langmuir isotherm, indicating that the Cr(Ⅵ) adsorption by PPR-Z is mostly chemical adsorption and exhibits single-layer adsorption. The saturated adsorption capacity of the adsorbent for Cr(Ⅵ) could reach 255.86 mg/g. The adsorbent could effectively reduce Cr(Ⅵ) to Cr(Ⅲ) and decrease the toxicity of Cr(Ⅵ) during adsorption. PPR-Z exhibited Cr(Ⅵ) selectivity in electroplating wastewater. The main mechanisms involved in the Cr(Ⅵ) adsorption are the chemical reduction of Cr(Ⅵ) into Cr(Ⅲ) and electrostatic and coordination interactions. Preparation of PPR-Z not only solves the problem of waste resin treatment but also effectively controls Cr(Ⅵ) pollution and realizes the concept of “treating waste with waste”.

关键词： waste amidoxime resin mesoporous adsorbent H_(3)PO_(4)and ZnCl_(2)processing Cr(VI)adsorption electroplating wastewater

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Preparation and properties of bifunctional Gd_(2)O_(3)/GQD composite nanoparticles

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Journal of Rare Earths 2022年第7期40卷 1118-1125页

作者： Chengjie Xu Meigui Ou Hao Zhou chunlin yang College of Materials and Metallurgy University of GuizhouGuiyang 550025China National Local Co-construction Engineering Laboratory for High Performance Metal Structure Material and Manufacture Technology Guiyang 550025China College of Chemistry and Materials Engineering Guiyang UniversityGuiyang 550003China

Nanocomposites of graphene quantum dots(GQDs)modified gadolinium oxide(Gd_(2)O_(3))particles were successfully synthesized.In addition,the effects of the amount of GQDs and the particle size of Gd_(2)O_(3)on the properties of nanocomposites were investigated.The structures and properties of nanoparticles were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,Fourier transform infrared spectroscopy,field emission scanning electron microscopy,transmission electron microscopy,photoluminescence spectrometry,and magnetic resonance imaging.The results show that the synthesized particles Gd_(2)O_(3)/GQD are spherical with a diameter of approximately 40 nm and have excellent fluorescence and magnetic property,and its relaxation rate(r_(1)=25.18(mmol/L)^(-1)/s)is higher than that of the typical commercial contrast agents Gd-DTPA(r_(1)=4.5(mmol/L)^(-1)/s),The fluorescence property of Gd_(2)O_(3)/GQD is optimized by varying the V_(GQDs):V_(Gd2O3)ratio,and 1:1 ratio of V_(GQDs):V_(Gd2O3)results in the best fluorescence property.The large particles of Gd_(2)O_(3)improve the relaxation property of nanocomposites.Therefore,the nanocomposites Gd_(2)O_(3)/GQD with magnetic and fluorescence characteristics can be used in biological imaging,drug targeting,and in-vivo diagnostic analysis.

关键词： Gd_(2)O_(3)/GQD Magnetic Fluorescence Magnetic resonance imaging(MRI) Rare earths

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Design methodology of a mini-missile considering flight performance and guidance precision

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Journal of Systems Engineering and Electronics 2024年第1期35卷 195-210页

作者： ZHANG Licong GONG chunlin SU Hua ANDREA Da Ronch Shaanxi Aerospace Flight Vehicle Design Key Laboratory School of AstronauticsNorthwestern Polytechnical UniversityXi’an 710072China Faculty of Engineering and Physical Sciences University of SouthamptonSouthampton SO171BJUnited Kingdom

The design of mini-missiles(MMs)presents several novel challenges.The stringent mission requirement to reach a target with a certain precision imposes a high guidance precision.The miniaturization of the size of MMs makes the design of the guidance,navigation,and control(GNC)have a larger-thanbefore impact on the main-body design(shape,motor,and layout design)and its design objective,i.e.,flight performance.Pursuing a trade-off between flight performance and guidance precision,all the relevant interactions have to be accounted for in the design of the main body and the GNC system.Herein,a multi-objective and multidisciplinary design optimization(MDO)is proposed.Disciplines pertinent to motor,aerodynamics,layout,trajectory,flight dynamics,control,and guidance are included in the proposed MDO framework.The optimization problem seeks to maximize the range and minimize the guidance error.The problem is solved by using the nondominated sorting genetic algorithm II.An optimum design that balances a longer range with a smaller guidance error is obtained.Finally,lessons learned about the design of the MM and insights into the trade-off between flight performance and guidance precision are given by comparing the optimum design to a design provided by the traditional approach.

关键词： mini-missiles(MMs) guidance navigation and control(GNC)system multi-objective optimization multidisciplinary design optimization(MDO) flight performance guidance precision

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Betulinic acid protects against ovarian impairment by decreasing F-2 toxin-induced oxidative stress and inflammation associated with the downregulation of p38 expression in mice

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Food Science and Human Wellness 2024年第3期13卷 1292-1302页

作者： Li Kong Xinyu Gao Lijuan Zhu Xing Lin You Huang chunlin Huang Wenjiang yang Yazhi Chen Haoqiang Zhao Jing Wu Zhihang Yuan Jin’e Yi Hunan Engineering Research Center of Livestock and Poultry Health Care College of Veterinary MedicineHunan Agricultural UniversityChangsha 410128China

F-2 toxin is an estrogenic mycotoxin that causes reproductive disorders in animals.Betulinic acid(BA)is a natural pentacyclic lupane-structure triterpenoid that has diverse pharmacological activities.In this study,the antioxidative and anti-inflammatory effects of BA and its underlying mechanism are explored in F-2 toxin-triggered mouse ovarian damage.We found that BA alleviated the F-2 toxin-induced ovarian impairment by stimulating follicle growth,reducing inflammatory cell infiltration,repairing damaged mitochondria and endoplasmic reticulum.Simultaneously,BA not only reversed F-2 toxin-induced reduction of follicle stimulating hormone(FSH)and luteinizing hormone(LH)levels in the serum,but also restrained the protein expression of the estrogen receptors a(ERa)and ERβ.Moreover,BA restored the balance of F-2 toxin-induced ovarian redox system disorders.Subsequently,we found that 0.25 mg/kg BA played an anti-inflammatory role in the F-2 toxin-induced ovarian impairment by decreasing interleukin-1β(IL-1β).IL-6,and tumor necrosis factor-α(TNF-α)mRNA expression,as well as inhibiting p38 protein expression.These data demonstrated that BA exerts its protective effect on F-2 toxin-induced ovarian oxidative impairment and inflammation by inhibiting p38 expression,which implies a natural product-based medicine to ameliorate F-2 toxin-caused female reproductive toxicity and provides a detoxifying method for food contaminated by mycotoxin.

关键词： Betulinic acid F-2 toxin Ovarian damage p38 MAPK signaling pathway

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Design Framework of Unsourced Multiple Access for 6G Massive IoT

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China Communications 2024年第1期21卷 1-12页

作者： chunlin Yan Siying Lyu Sen Wang Yuhong Huang Xiaodong Xu China Mobile Communication Research Institute Beijing 100053China ZGC Institute of Ubiquitous-X Innovation and Applications Beijing 100080China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

In this paper,ambient IoT is used as a typical use case of massive connections for the sixth generation(6G)mobile communications where we derive the performance requirements to facilitate the evaluation of technical solutions.A rather complete design of unsourced multiple access is proposed in which two key parts:a compressed sensing module for active user detection,and a sparse interleaver-division multiple access(SIDMA)module are simulated side by side on a same platform at balanced signal to noise ratio(SNR)operating points.With a proper combination of compressed sensing matrix,a convolutional encoder,receiver algorithms,the simulated performance results appear superior to the state-of-the-art benchmark,yet with relatively less complicated processing.

关键词： channel coding compressed sensing massive Internet-of-Things(IoT) sparse interleaverdivision multiple access(SIDMA) the sixth generation(6G)mobile communications unsourced multiple access

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Terrorism Attack Classification Using Machine Learning: The Effectiveness of Using Textual Features Extracted from GTD Dataset

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1427-1467页

作者： Mohammed Abdalsalam chunlin Li Abdelghani Dahou Natalia Kryvinska School of Computer Science and Technology Wuhan University of TechnologyWuhan430070China LDDI Laboratory Faculty of Science and TechnologyUniversity of Ahmed DRAIAAdrar01000Algeria Information Systems Department Faculty of ManagementComenius UniversityBratislava82005Slovakia

One of the biggest dangers to society today is terrorism, where attacks have become one of the most significantrisks to international peace and national security. Big data, information analysis, and artificial intelligence (AI) havebecome the basis for making strategic decisions in many sensitive areas, such as fraud detection, risk management,medical diagnosis, and counter-terrorism. However, there is still a need to assess how terrorist attacks are related,initiated, and detected. For this purpose, we propose a novel framework for classifying and predicting terroristattacks. The proposed framework posits that neglected text attributes included in the Global Terrorism Database(GTD) can influence the accuracy of the model’s classification of terrorist attacks, where each part of the datacan provide vital information to enrich the ability of classifier learning. Each data point in a multiclass taxonomyhas one or more tags attached to it, referred as “related tags.” We applied machine learning classifiers to classifyterrorist attack incidents obtained from the GTD. A transformer-based technique called DistilBERT extracts andlearns contextual features from text attributes to acquiremore information from text data. The extracted contextualfeatures are combined with the “key features” of the dataset and used to perform the final classification. Thestudy explored different experimental setups with various classifiers to evaluate the model’s performance. Theexperimental results show that the proposed framework outperforms the latest techniques for classifying terroristattacks with an accuracy of 98.7% using a combined feature set and extreme gradient boosting classifier.

关键词： Artificial intelligence machine learning natural language processing data analytic DistilBERT feature extraction terrorism classification GTD dataset

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Autotomy and Regeneration of Appendages in Crustaceans:A Review

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Journal of Ocean University of China 2024年第3期23卷 731-742页

作者： LIU Lei TAO Dandan WANG chunlin FU Yuanyuan WANG Sixiang HUANG Xinlian ZHAI Wei SONG Weiwei School of Marine Sciences Ningbo UniversityNingbo 315832China Ningbo Institute of Oceanography Ningbo 315832China

Autotomy of appendages is a self-protection mechanism in crustaceans,which is defined as the reflexive loss of a limb in response to predation,competition,or other environmental factors.Single-limb injuries were the most common among the species surveyed in the present study,and the chelicerae were the most frequently lost appendages.After autotomy,hormones and signaling pathways are altered.Loss of limbs can affect foraging efficiency,although cheliped loss may be compensated by shifting to alternative prey or using both motor and oral appendages.In heterogeneous species,the loss of the major chelae may affect the selectivity of feeding.Autotomy can affect crustacean growth by reducing size increases at molting and altering the timing of ecdysis.In commercial production,removing chelicerae is an effective strategy to reduce cannibalism,and production of soft-shell crabs can be increased via autotomy.After autotomy,a new limb will regrow through regeneration and molting.This process involves the regulation of hormones,regrowth of nerves,and a number of signaling pathways that include the Wnt/β-catenin signaling pathway and transforming growth factorβsignaling pathway.Crustaceans are somewhat different from vertebrates in terms of regeneration.This review provides theoretical guidance about autotomy and regeneration applied in artificial aquaculture,and we offer several suggestions for future research on autotomy and regeneration in crustaceans.

关键词： autotomy regeneration appendages crustaceans

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New Problems of Boiler Corrosion after Coupling Combustion of Coal and Biomass and Anti-Corrosion Technologies

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Journal of Renewable Materials 2024年第4期12卷 799-814页

作者： Lei Wang Ziran Ma chunlin Zhao Jiali Zhou Hongyan Wang Ge Li Ningling Zhou National Institute of Clean-and-Low-Carbon Energy Beijing102211China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy&EnvironmentSoutheast UniversityNanjing210096China

This study explores the corrosion issues arising from the coupled combustion of coal and biomass and proposes potential solutions.Biomass,as a renewable energy source,offers advantages in energy-saving and carbon reduction.However,the corrosive effects of alkali metal compounds,sulfur(S)and chlorine(Cl)elements in the ash after combustion cannot be underestimated due to the high volatile content of biomass fuels.We investigate the corrosion mechanisms,as well as the transfer of Cl and alkali metal elements during this process.Comparative corrosion analyses are conducted among coal-fired boilers,pure biomass boilers and boilers with coupled combustion.Various biomass types in co-firing are studied to understand different corrosion outcomes.The main factors influencing corrosion include the physicochemical properties of biomass feedstock,furnace temperature and heating surface materials,with the chemical composition and ash content of biomass playing a dominant role.Currently,the methods used for anti-corrosion include water washing pretreatment of biomass feedstock,application of novel alloys and coatings and the development of additives to inhibit fouling,ash deposition and corrosion.Efficient inhibitors are economical and easy to produce.Additionally,biomass can be converted into biomass gasification gas,although challenges related to tar still need to be addressed.

关键词： Biomass coupled combustion corrosion mechanism anti-corrosion measures

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