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Multi-component decompositions, linear superpositions, and new nonlinear integrable coupled KdV-type systems

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Communications in Theoretical Physics 2025年第2期77卷 3-14页

作者： Xiazhi Hao S Y lou School of Mathematical Science Zhejiang University of Technology School of Physical Science and Technology Ningbo University

In the realm of nonlinear integrable systems, the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrability. By focusing on single-component decompositions within the potential BKP hierarchy, it has been observed that specific linear superpositions of decomposition solutions remain consistent with the underlying equations. Moreover, through the implementation of multi-component decompositions within the potential BKP hierarchy,successful endeavors have been undertaken to formulate linear superposition solutions and novel coupled Kd V-type systems that resist decoupling via alterations in dependent variables.

关键词： integrable system single-component decomposition multi-component decomposition linear superposition integrable coupled KdV-type system

Multi-interface structure design of bamboo-based carbon/Co/CoO composite electromagnetic wave absorber based on biomimetic honeycomb-shaped superstructure

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 631-644页

作者： Yanting Wang He Han Huiyang Bian Yanjun Li Zhichao lou Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China College of Light Industry and Food Engineering Nanjing Forestry UniversityNanjing 210037China

The rapid development of 5G communication technology and smart electronic and electrical equipment will inevitably lead to electromagnetic radiation *** heterointerface polarization relaxation through nanostructure design and interface modifica-tion has proven to be an effective strategy to obtain efficient electromagnetic wave ***,this work implements an innovative method that combines biomimetic honeycomb superstructure to constrain hierarchical porous heterostructure composed of Co/CoO nano-particles to improve the interfacial polarization *** method effectively controlled the absorption efficiency of Co^(2+)through de-lignification modification of bamboo,and combined with the bionic carbon-based natural hierarchical porous structure to achieve uniform dispersion of nanoparticles,which is conducive to the in-depth construction of heterogeneous *** addition,the multiphase struc-ture brought about by high-temperature pyrolysis provides the best dielectric loss and impedance matching for the ***,the obtained bamboo-based Co/CoO multiphase composite showed excellent electromagnetic wave absorption performance,achieving excel-lent reflection loss(RL)of-79 dB and effective absorption band width of 4.12 GHz(6.84-10.96 GHz)at low load of 15wt%.Among them,the material’s optimal radar cross-section(RCS)reduction value can reach 31.9 dB·m^(2).This work provides a new approach to the micro-control and comprehensive optimization of macro-design of microwave absorbers,and offers new ideas for the high-value utiliza-tion of biomass materials.

关键词： biomass honeycomb porous heterojunction structure interfacial polarization electromagnetic wave absorption

Study of the Transport Behavior of Multispherical Proppant in Intersecting Fracture Based on Discrete Element Method

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Energy Engineering 2025年第1期122卷 185-201页

作者： Chengyong Peng JianshuWu Mao Jiang Biao Yin Yishan lou CNOOC Research Institute Company Limited Beijing100028China School of Petroleum Engineering Yangtze UniversityWuhan430100China Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering(Yangtze University) Wuhan430100China

To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fractures,this study considered the combined impact of geological-engineering factors on *** reservoir production parameters and the discrete elementmethod,multispherical proppants were ***,a 3D fracture model,based on the specified conditions of the L block,employed coupled(Computational Fluid Dynamics)CFD-DEM(Discrete ElementMethod)for joint simulations to quantitatively analyze the transport and placement patterns of multispherical proppants in intersecting *** indicate that turbulent kinetic energy is an intrinsic factor affecting proppant ***,the efficiency of placement and migration distance of low-sphericity quartz sand constructed by the DEM in the main fracture are significantly reduced compared to spherical ceramic proppants,with a 27.7%decrease in the volume fraction of the fracture surface,subsequently affecting the placement concentration and damaging fracture *** to small-angle fractures,controlling artificial and natural fractures to expand at angles of 45°to 60°increases the effective support length by approximately 20.6%.During hydraulic fracturing of gas wells,ensuring the fracture support area and post-closure conductivity can be achieved by controlling the sphericity of proppants and adjusting the perforation direction to control the direction of artificial fractures.

关键词： Hydraulic fracturing discrete element method proppant sphericity CFD-DEM

术前超声内镜引导下细针穿刺对可切除胰腺癌诊断之安全性和准确性的探讨

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中国内镜杂志 2016年第7期22卷 5-9页

作者：黄平张筱凤吕文楼颂梅范震浙江省杭州市第一人民医院消化科浙江杭州310006

目的探讨术前超声内镜引导下细针穿刺(EUS-FNA)对可切除胰腺癌患者诊断之安全性及准确性。方法回顾性分析该院2010年1月-2014年12月256例胰腺癌患者的临床资料,其中82例有手术切除的指征:54例术前行EUS-FNA术(FNA+组)和28例无术前EUS-FN... 详细信息

目的探讨术前超声内镜引导下细针穿刺(EUS-FNA)对可切除胰腺癌患者诊断之安全性及准确性。方法回顾性分析该院2010年1月-2014年12月256例胰腺癌患者的临床资料,其中82例有手术切除的指征:54例术前行EUS-FNA术(FNA+组)和28例无术前EUS-FNA(FNA-组),观察EUS-FNA的诊断情况及两组患者的生存时间。结果 FNA+组54患者EUS均见肿瘤病灶,所有患者FNA均成功。根据细胞学和组织学,EUS-FNA诊断的准确性分别为94.44%(51/54)和88.89%(48/54),总准确率为94.44%(51/54)。2例EUS-FNA后出现轻度胰腺炎,2例并发出血,经保守治疗后痊愈,无其他严重并发症。在FNA+和FNA-组的中位无复发存活时间分别为282和265 d(P>0.05),平均总生存时间分别为568和557 d(P>0.05)。FNA+组的RFS和OS并不逊色于FNA-组。这些数据表明,EUS-FNA并不影响中位无复发存活期或总生存期,也没有增加其他并发症的风险。结论术前EUS-FNA对可切除胰腺癌患者是一种安全、准确的诊断方法。

关键词：胰腺癌超声内镜引导下细针穿刺术前诊断

Applications of Deep Learning in Mineral Discrimination:A Case Study of Quartz,Biotite and K-Feldspar from Granite

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Journal of Earth Science 2025年第1期36卷 29-45页

作者： Wei lou Dexian Zhang Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitor(Central South University) MinistryofEducationChangsha 410083China School of Geosciences&Info-Physics Central SouthUniversity Changsha 410083China

Mineral identification and discrimination play a significant role in geological *** mineral discrimination based on deep learning has the advantages of automation,low cost,less time consuming and low error *** this article,characteristics of quartz,biotite and Kfeldspar from granite thin sections under cross-polarized light were studied for mineral images intelligent classification by Inception-v3 deep learning convolutional neural network(CNN),and transfer learning *** images from multi-angles were employed to enhance the accuracy and reproducibility in the process of mineral *** results show that the average discrimination accuracies of quartz,biotite and K-feldspar are 100.00%,96.88%and 90.63%.Results of this study prove the feasibility and reliability of the application of convolution neural network in mineral images *** study could have a significant impact in explorations of complicated mineral intelligent discrimination using deep learning methods and it will provide a new perspective for the development of more professional and practical mineral intelligent discrimination tools.

关键词： deep learning mineral discrimination Inception-v3 CNN transfer learning convolutional neural network

Tuning support morphology to control alloy over PtCo/γ-Al_(2)O_(3) for the preferential oxidation of CO

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燃料化学学报(中英文) 2025年第1期53卷 96-105页

作者： song Lichuan ZHONG Liding SHEN Jia lou Yake GUO Yun WANG Li State Key Laboratory of Green Chemical Engineering and Industrial Catalysis Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

The preferential oxidation of CO(CO-PROX)reaction is a cost-effective method for eliminating trace amounts of CO from the fuel ***-based catalysts have been extensively studied for COPROX,with their activity influenced by the morphology of the *** synthesis was employed to produce different morphologies ofγ-Al_(2)O_(3):flower-likeγ-Al_(2)O_(3)(f)exposing(110)crystal faces,sheet-likeγ-Al_(2)O_(3)(s)revealing(100)crystal faces,and rod-likeγ-Al_(2)O_(3)(r)displaying(111)crystal faces,followed by loading PtCo *** exposed crystal faces of the support impact the alloying degree of the PtCo nanoparticles,and an increase in the alloying degree correlates with enhanced catalyst ***_(3)Co intermetallic compounds were identified onγ-Al_(2)O_(3)(f)exposing(110)crystal faces,and PtCo/γ-Al_(2)O_(3)(f)showed high catalytic activity in the CO-PROX reaction,achieving 100%CO conversion across a broad temperature range of 50−225°*** contrast,only partial alloying of PtCo was observed onγ-Al_(2)O_(3)(s).Furthermore,no alloying between Pt and Co occurred in PtCo/γ-Al_(2)O_(3)(r),resulting in a reaction rate at 50°C that was merely 11%of that of PtCo/γ-Al_(2)O_(3)(f).The formation of Pt3Co intermetallic compounds led to a more oxidized state of Pt,which significantly diminished the adsorption of CO on Pt and augmented the active oxygen species,thereby facilitating the selective oxidation of CO.

关键词： PtCo catalysts γ-Al_(2)O_(3) support morphology CO-PROX

Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 504-514页

作者： lou Zhang Shuo Li Fu Tang Jingkai Zhang Yuetong Kang Hean Zhang Lidong Li State Key Laboratory for Advanced Metals and Materials School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial ***,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water *** this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing *** analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag *** surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their *** the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite *** inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag *** prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.

关键词： silver nanoparticles hydrogel straw extraction antibacterial

Desymmetrized pillar[8]arenes:High-yield synthesis,functionalization,and host-guest chemistry

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Chinese Chemical Letters 2025年第1期36卷 288-292页

作者： Jie Yang Xin-Yue lou Dihua Dai Jingwei Shi Ying-Wei Yang College of Chemistry Jilin UniversityChangchun 130012China School of Life Sciences Jilin UniversityChangchun 130012China Department of Laboratory Medicine Center China-Japan Union Hospital of Jilin UniversityChangchun 130033China

The preparation,functionalization,and investigations in host-guest properties of high-level pillararene macrocycles have long been a big challenge because of the lack of efficient synthetic ***,a novel type of pillararene derivative,namely desymmetrized pillar[8]arene(DP[8]A),has been successfully synthesized via a facile two-step strategy with high *** with its pillar[8]arene counterpart,DP[8]A is composed of four alkoxy-substituted benzene units and four bare benzene *** crystal analysis has been performed in order to unveil the molecular conformation and packing mode of DP[8]A,which indicated that DP[8]A possesses a unique chair-like structure and much smaller steric *** functional theory(DFT)calculations and electrostatic potential map suggested the inhomogeneous electronic distribution in the DP[8]A ***-soluble carboxylate-modified DP[8]A,that is,CDP[8]A,was also prepared to investigate the host-guest properties in aqueous solution with methyl viologen(MV),where the binding constant and morphologies of the formed host-guest complexes have been *** all,this new version of eight-membered pillararene derivative might potentially serve as a powerful macrocycle candidate for further applications in supramolecular chemistry.

关键词： Host-guest interaction Macrocycle chemistry Pillararenes Supramolecular chemistry Synthetic macrocycles

Modulated synthesis of stoichiometric and sub-stoichiometric two-dimensional covalent organic frameworks for enhanced ethylene purification

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Chinese Chemical Letters 2025年第1期36卷 272-276页

作者： Jiahao Li Guinan Chen Chunhong Chen Yuanyuan lou Zhihao Xing Tao Zhang Chengtao Gong Yongwu Peng College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing University of Posts and TelecommunicationsNanjing 210023China

Controlled synthesis of two-dimensional covalent organic frameworks(2D COFs),including stoichiometric and sub-stoichiometric variations,is a topic of growing interest due to its potential in gas separation *** this study,we successfully synthesized three distinct 2D COFs by carefully adjusting solvent compositions and monomer ratios during the synthesis of[4+4]type *** included a stoichiometric[4+4]type COF and two sub-stoichiometric[4+2]type COFs,featuring unreacted amino or formyl *** resulting COFs exhibit different gas adsorption and separation ***,sub-stoichiometric COF-DA with residual amino groups shows comparable adsorption capacity for C_(2)H_(2),C_(2)H_(4),and CO_(2)to stoichiometric *** contrast,sub-stoichiometric COF-Py with residual formyl groups displays enhanced adsorption selectivity for C_(2)H_(2)/C_(2)H_(4)and C_(2)H_(2)/CO_(2)separation,with the C_(2)H_(2)/C_(2)H_(4)selectivity being the highest among reported COFs,attributed to increased pore polarity resulting from the presence of formyl *** study not only offers an additional example of substoichiometric COF synthesis but also advocates for further exploration of sub-stoichiometric COF materials,particularly in the field of gas adsorption and separation.

关键词： Two-dimensional covalent organic frameworks Stoichiometric and sub-stoichiometric Residual functional groups Ethylene purification