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Applying an Improved Dung Beetle Optimizer Algorithm to Network Traffic Identification

Computers, Materials & Continua 2024年第3期78卷 4091-4107页

作者： Qinyue wu hui Xu Mengran Liu School of Computer Science Hubei University of TechnologyWuhan430068China

Network traffic identification is critical for maintaining network security and further meeting various demands of network ***,network traffic data typically possesses high dimensionality and complexity,leading to practical problems in traffic identification data *** the original Dung Beetle Optimizer(DBO)algorithm,Grey Wolf Optimization(GWO)algorithm,Whale Optimization Algorithm(WOA),and Particle Swarm Optimization(PSO)algorithm have the shortcomings of slow convergence and easily fall into the local optimal solution,an Improved Dung Beetle Optimizer(IDBO)algorithm is proposed for network traffic ***,the Sobol sequence is utilized to initialize the dung beetle population,laying the foundation for finding the global optimal ***,an integration of levy flight and golden sine strategy is suggested to give dung beetles a greater probability of exploring unvisited areas,escaping from the local optimal solution,and converging more effectively towards a global optimal ***,an adaptive weight factor is utilized to enhance the search capabilities of the original DBO algorithm and accelerate *** the improvements above,the proposed IDBO algorithm is then applied to traffic identification data analytics and feature selection,as so to find the optimal subset for K-Nearest Neighbor(KNN)*** simulation experiments use the CICIDS2017 dataset to verify the effectiveness of the proposed IDBO algorithm and compare it with the original DBO,GWO,WOA,and PSO *** experimental results show that,compared with other algorithms,the accuracy and recall are improved by 1.53%and 0.88%in binary classification,and the Distributed Denial of Service(DDoS)class identification is the most effective in multi-classification,with an improvement of 5.80%and 0.33%for accuracy and recall,***,the proposed IDBO algorithm is effective in increasing the efficiency of traffic identificati

关键词： Network security network traffic identification data analytics feature selection dung beetle optimizer

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Flame Synthesis of Zr/ZSM-5 Catalysts with Tunable Acidity for the Oxidative Dehydrogenation of Propane to Propene

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Journal of Thermal Science 2024年第1期33卷 268-283页

作者： DANIEL Samuel FONZEU MONGUEN Cedric Karel wu Lingnan tian Zhenyu Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Tuning the surface acidity of ZSM-5 catalyst is essential to achieve desired propene selectivity and *** several ratios of Zr were utilized to modify ZSM-5 via flame spray pyrolysis technique coupled with a pulse spray evaporation *** interaction between Zr and ZSM-5 in the flame influenced the physicochemical and acidity properties of the Zr/*** increasing Zr ratio in ZSM-5 shows coated layers of irregular nano-sized Zr with an increase in crystallite sizes due to the synergetic effect between Zr and *** surface chemical analysis revealed increased lattice oxygen on the Zr modified ZSM-5(1:4) sample compared to other *** acidity analysis revealed the Lewis and Br?nsted acid distribution in the weak and medium acid sites on the catalyst ***,the increase in Zr loading decreased the concentration of Br?nsted acid sites and tuned the catalyst surface to more Lewis acidity,promoting propene selectivity and hindering the over-oxidation of *** modified ZSM-5 catalysts were examined in a fixed bed reactor within 300℃-700℃ at a gas hourly space velocity(GHSV) of 6000 mL·g(catalysts)^(-1)·h^(-1) for the oxidative dehydrogenation of propane(ODHP) to *** the catalysts,Zr/ZSM-5(1:4) exhibited the best propene yield, with 57.19% propane conversion and 75.54% selectivity to propene and the highest *** work provides a promising strategy for tuning the surface acidity of ZSM-5 with Zr for ODHP applications.

关键词： flame synthesis Zr modified ZSM-5 catalyst ODHP surface acidity lattice oxygen

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Numerical and experimental research on axial injection end-burning hybrid rocket motors with polyethylene fuel

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Chinese Journal of Aeronautics 2024年第8期37卷 91-105页

作者： Xiangyu MENG hui tian Lingfei HE Jingfei GAO Xiaoting NIU Guobiao CAI School of Astronautics Beihang UniversityBeijing 100191China Key Laboratory of Spacecraft Design Optimization&Dynamic Simulation Technologies Ministry of EducationBeijing 100816China

This study investigates the end-burning hybrid rocket motors with polyethylene fuel by the numerical simulation and *** on computational fluid dynamics,a numerical model is *** model is validated by two firing tests in this hybrid rocket motor,which uses oxygen and polyethylene as *** results show that the numerical and experimental data are in good agreement,and the error of the chamber pressure is less than 2.63%.Based on the simulation mode,the blowoff limit of the end-burning hybrid rocket motors is *** the nozzle throat diameter and the inner diameter of grain are large,it is more difficult for the hybrid rocket motor to achieve end-burning mode,i.e.,the flame spreading is prevented in the narrow *** main reason is that when the nozzle throat and the grain port are large,chamber pressure and oxidizer flow velocity are ***,the friction velocity considering the pressure and flow velocity is *** critical friction velocity is about 4.054–4.890 m/s in the hybrid rocket *** the friction velocity exceeds the critical friction velocity,the combustion mode in hybrid rocket motors changes from the flame spreading mode to the end-burning ***,the regression rate formula is obtained by fitting,which shows that the regression rate has a good correlation with combustion chamber *** critical friction velocity and regression rate formula can provide an important reference for end-burning hybrid rocket motors.

关键词： Hybrid rocket motor End burning Blowoff limit Flame propagation Regression rate

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Synthesis of covalent organic framework materials and their application in the field of sensing

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Nano Research 2024年第1期17卷 162-195页

作者： Weiyu Zhang Shiwei Liu Qihua Sun Ning tian Zhaofeng wu Xinjiang Key Laboratory of Solid-State Physics and Devices Urumqi 830046China School of Physics Science and Technology Xinjiang UniversityUrumqi 830046China

Covalent organic frameworks(COFs)are an emerging type of porous crystalline polymers formed by combining strong covalent bonds with organic building *** to their large surface area,high intrinsic pore space,good crystallization properties,high stability,and designability of the resultant units,COFs are widely studied and used in the fields of gas adsorption,drug transport,energy storage,photoelectric catalysis,electrochemistry,and *** recent years,the rapid development of the Internet of Things and people’s yearning for a better life have put forward higher and more requirements for sensors,which are the core components of the Internet of ***,this paper reviews the recent progress of COFs in synthesis methods and sensing applications,especially in the last five *** paper first introduces structure,properties,and synthesis methods of COFs and discusses advantages and disadvantages of different synthesis ***,the research progress of COFs in different sensing fields,such as metal ion sensors,gas sensors,biomedical sensors,humidity sensors,and pH sensors,is introduced *** and prospects are also presented in order to provide a reference for researchers concerned with COFs and sensors.

关键词： covalent organic framework materials structural design and synthesis sensing application gas sensors

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Growth,optical dispersion and magnetic behavior of Dy^(3+) doped yttrium iron garnet crystals

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Journal of Rare Earths 2024年第6期42卷 1110-1117,I0004页

作者： Yating Fang hui Shen Yudie Ma Shijie Liao Shuang Xia tian tian Ding Zhou Yunfeng Ma Jiayue Xu Institute of Crystal Growth School of Materials Science and EngineeringShanghai Institute of Technology National Engineering Center of Electromagnetic Radiation Control Materials School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of China

Y_(3)Fe_(5)O_(12)(YIG)crystals are highly desirable for the fabrication of mid-infrared isolators with the rapid growth of optical communications,although it is rather challenging to grow large size and high-quality single ***^(3+)doping is expected to improve the optical and magneto-optical prope ***,high quality Dy:YIG crystals and the adjustment of Dy^(3+)on the structure and optical behavior of YIG crystal remain unclear,impeding its practical ***,a series of Y_(3-x)Dy_(x)Fe_(5)O_(12)(x=0,0.5,1.0,1.5,3)solid solution crystals was grown by the flux-Bridgman method and single crystals up to 25 mm were *** the introduction of Dy^(3+),lattice parameters are gradually enlarged from 1.2379 nm(YIG)to 1.2420 nm(DyIG).Typical Dy^(3+)absorption peaks are observed around 1070,1265 and 1670 *** refractive index decreases from 2.37(500 nm)to 2.10(2500 nm)for YIG crystal,and it reduces from 2.47(500 nm)to 2.16(2500 nm)for DyIG *** optical bandgaps remain almost unchanged for Dy:YIG *** optical dispersion of the refractive indices was finely fitted by the Wemple and DiDomenico(WDD)and the Sellmeier models,*** the increase of Dy^(3+)content,the saturation magnetization(Ms)decreases significantly from 23.62 emu/g(YIG)to 5.33 emu/g(DyIG).Small coercive field is persisted for this system,endowing small external magnetic *** results provide valuable references for the manipulation of rare earths on the properties of magnetooptical crystals,which is beneficial to the design of high-performance garnet crystals for the application of optical switching and non-reciprocal related devices.

关键词： Magneto-optical crystal Yttrium iron garnet Dy^(3+)doping Crystal growth Optical dispersion Rare earths

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Lake microbiome composition determines community adaptability to warming perturbations

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Ecological Processes 2024年第2期13卷 177-191页

作者： Xiaotong wu Qixing Zhou hui Zeng Xiangang Hu Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education) Carbon Neutrality Interdisciplinary Science Centre/College of Environmental Science and Engineering Nankai University

Background Microbial communities are crucial for ecosystems. A central goal of microbial ecological research is to simplify the biodiversity in natural environments and quantify the functional roles to explore how the ecosystems respond under different environmental conditions. However, the research on the stability and dynamics of lake microbes in response to repeated warming stress is *** To exclude confounding environmental factors, we conducted a 20-day repeated warming simulation experiment to examine the composition and function dynamics of lake microbial *** Experimental warming significantly altered the community structure of bacteria instead of fungi. Microbial community structure, together with microbial biomass, jointly regulated the function of microbial communities. The plummeting of aerobic denitrifiers Pseudomonadaceae decreased by 99%(P < 0.001) after high temperature, leading to reduced microbial nitrogen metabolism on nitrogen respiration and nitrate respiration. Under warming conditions, the microbial community with higher adaptability showed more positive correlations and less competitive relationships in co-occurrence networks to acclimate to *** Microbiome composition controlled carbon and nitrogen metabolism, thus determining lake microbial communities' adaptability to heat stress. This study extended our insights on the lake microbial community response and adaptability under warming drivers.

关键词： Temperature Environmental stress Bacteria Fungi Freshwater ecosystem

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Huangqin Decoction Delays Progress of Colitis-Associated Carcinogenesis by Regulating Nrf2/HO-1 Antioxidant Signal Pathwayin Mice

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Chinese Journal of Integrative Medicine 2024年第2期30卷 135-142页

作者： GU Li-mei LI He-zhong GAO Lei LI hui WEI Lan-fu PAN Cheng-yu wu Ke-xuan tian Yao-zhou Department of Gastrointestinal Endoscopy Affiliated Hospital of Nanjing University of Chinese MedicineNanjing(210029)China Department of Gastroenterology Affiliated Hospital of Integrated Traditional Chinese and Western MedicineNanjing University of Chinese MedicineNanjing(210028)China School of Integrated Chinese and Western Medicine Nanjing University of Chinese MedicineNanjing(210023)China

Objective:To investigate the effect of Huangqin Decoction(HQD)on nuclear factor erythroid 2 related-factor 2(Nrf2)/heme oxygenase(HO-1)signaling pathway by inducing the colitis-associated carcinogenesis(CAC)model mice with azoxymethane(AOM)/dextran sodium sulfate(DSS).Methods:The chemical components of HQD were analyzed by liquid chromatography-quadrupole-time-of-flight mass spectrometry(LC-Q-TOF-MS/MS)to determine the molecular constituents of *** 48 C57BL/6J mice were randomly divided into 6 groups by a random number table,including control,model(AOM/DSS),mesalazine(MS),low-,medium-,and high-dose HQD(HQD-L,HQD-M,and HQD-H)groups,8 mice in each *** for the control group,the mice in the other groups were intraperitoneally injected with AOM(10 mg/kg)and administrated with 2.5%DSS orally for 1 week every two weeks(totally 3 rounds of DSS)to construct a colitis-associated carcinogenesis mouse *** mice in the HQD-L,HQD-M and HQD-H groups were given HQD by gavage at doses of 2.925,5.85,and 11.7 g/kg,respectively;the mice in the MS group was given a suspension of MS at a dose of 0.043 g/kg(totally 11 weeks).The serum levels of malondialdehyde(MDA)and superoxide dismutase(SOD)were measured by enzyme-linked immunosorbent *** mRNA and protein expression levels of Nrf2,HO-1,and inhibitory KELCH like ECH-related protein 1(Keap1)in colon tissue were detected by quantitative real-time PCR,immunohistochemistry,and Westem blot,***:LC-Q-TOF-MS/MS analysis revealed that the chemical constituents of HQD include baicalin,paeoniflorin,and glycyrrhizic *** to the control group,significantly higher MDA levels and lower SOD levels were observed in the model group(P<0.05),whereas the expressions of Nrf2 and HO-1 were significantly decreased,and the expression of Keap1 increased(P<0.01).Compared with the model group,serum MDA level was decreased and SOD level was increased in the HQD-M,HQD-H and MS groups(P<0.05).Higher expressions of

关键词： Huangqin Decoction colitis-associated carcinogenesis nuclear factor erythroid 2 related-factor 2/heme oxygenase signaling pathway oxidative stress Chinese medicine

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Elaborations of the influencing factors on the formation of secondary inorganic aerosols in a heavily polluted urban area of China

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Journal of Environmental Sciences 2024年第4期138卷 406-417页

作者： Shuang Wang Qiyuan Wang Ting Zhang Suixin Liu Steven Sai Hang Ho Jie tian hui Su Yong Zhang Luyao Wang Tingting wu Junji Cao School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China Key Laboratory of Aerosol Chemistry and Physics State Key Laboratory of Loess and Quaternary GeologyInstitute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain Xi’an 710061China Division of Atmospheric Sciences Desert Research InstituteRenoNevada89512United States Hong Kong Premium Services and Research Laboratory KowloonHong Kong SARChina Xi’an Institute for Innovative Earth Environment Research Xi’an 710061China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

In this study,online water-soluble inorganic ions were detected to deduce the formation mechanism of secondary inorganic aerosol in Xianyang,China during *** dominant inorganic ions of sulfate(SO_(4)^(2-)),nitrate(NO_(3)^(-)),and ammonium(NH_(4)^(+))(the sum of those is abbreviated as SNA)accounted for 17%,21%,and 12% of PM_(2.5)mass,*** the air quality deteriorated from excellent to poor grades,the precursor gas sulfur dioxide(SO_(2))of SO_(4)^(2-)increased and then decreased with a fluctuation,while nitrogen dioxide(NO_(2))and ammonia(NH_(3)),precursors of NO_(3)^(-)and NH_(4)^(+),and SNA show increasing *** factors including boundary layer height(BLH),temperature,and wind speed also show decline trends,except relative humidity(RH).Meanwhile,the secondary conversion ratio shows a remarkable increasing trend,indicating that there was a strong secondary *** the perspective of chemical mechanisms,RH is positively correlated with sulfur oxidation ratios(SOR),nitrogen oxidation ratios(NOR),and ammonia conversion ratios,representing that the increase of humidity could promote the generation of ***,SOR and NOR were also positively related to the *** the one hand,the low wind speed and BLH led to the accumulation of *** the other hand,the increases of RH and ammonia promoted more formations of SNA and PM_(2.5).The results advance our identification of the contributors to the haze episodes and assist to establish more efficient emission controls in Xianyang,in addition to other cities with similar emission and geographical characteristics.

关键词： Haze episodes Secondary inorganic aerosol Secondary conversion ratio Meteorological factors

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Phase field modeling of grain stability of nanocrystalline alloys by explicitly incorporating mismatch strain

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Rare Metals 2024年第7期43卷 3370-3382页

作者： Min Zhou Hong-hui wu Yuan wu hui Wang Xiong-Jun Liu Sui-He Jiang Xiao-Bin Zhang Zhao-Ping Lu Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083Cnina Institute for Carbon Neutrality University of Science and TechnologyBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

Ab st ra ct Nanocrystalline materials exhibit unique properties due to their extremely high grain boundary(GB) ***,this high-density characteristic induces grain coarsening at elevated temperatures,thereby limiting the widespread application of nanocrystalline *** experimental observations revealed that GB segregation and second-phase pinning effectively hinder GB migration,thereby improving the stability of nanocry stalline *** this study,a mouified phase-field model that integrates mismatch strain,solute segregation and precipitation was developed to evaluate the influence of lattice misfit on the thermal stability of nanocrystalline *** simulation results indicated that introducing a suitable mismatch strain can effectively enhance the microstructural stability of nanocrystalline *** synergizing precipitation with an appropriate lattice misfit,the formation of second-phase particles in the bulk grains can be suppressed,thereby facilitating solute segregation/precipitation at the *** concentrated solute segregation and precipitation at the GBs effectively hinders grain migration,thereby preventing grain *** findings provide a new perspective on the design and regulation of nanocrystalline alloys with enhanced thermal stability.

关键词： Phase field model Mismatch strain Second-phase precipitation Grain boundary segregation Nanocrystalline alloys

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Synergistic Ru/RuO_(2) heterojunctions stabilized by carbon coating as efficient and stable bifunctional electrocatalysts for acidic overall water splitting

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Nano Research 2024年第8期17卷 6931-6939页

作者： Man wu Yuying Fan Yang Huang Dongxu Wang Ying Xie Aiping wu Chungui tian Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080China

The development of highly active and stable acidic water oxidation electrocatalysts is of great significant for promoting the industrial application of proton exchange membrane ***-based catalysts have broad application prospects in acidic water oxidation,but their limitations in stability and activity hinder their further ***,a nitrogen-doped carbon(NC)coated porous Ru/RuO_(2) heterojunctional hollow sphere(Ru/RuO_(2)/NC)is designed as high-active and stable bifunctional electrocatalyst for acidic oxygen evolution reaction(OER)and hydrogen evolution reaction(HER).In synthesis,the key is to use mesoporous polydopamine spheres as a template for forming hollow spheres,a source of NC coating and a reducing agent for forming Ru/RuO_(2) *** Ru/RuO_(2) heterojunction adjusts the electronic structure of Ru active sites,optimizing the adsorption of intermediate ***,the NC coating and the interaction between NC and Ru/RuO_(2) effectively prevent Ru from over-oxidation and *** porous hollow structure provides more exposed active sites and promotes mass ***,Ru/RuO_(2)/NC exhibits outstanding OER and HER performance with low overpotentials of 211 and 32 mV at 10 mA·cm^(−2),respectively,and shows excellent *** acid water splitting electrolyzer,based on the bifunctional Ru/RuO_(2)/NC,requires low cell voltages of 1.46 and 1.76 V at 10 and 100 mA·cm^(−2),respectively,with good stability for over 100 h operation,surpassing Pt/C||RuO_(2) and most of the reported catalysts.

关键词： hollow heterojunction bifunctional electrocatalysts oxygen evolution hydrogen evolution acidic water splitting

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