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Journal of Iron and Steel Research International 2024年第4期31卷 924-932页

作者： Wei liu yan Wang Li-xiong Han Ying-kang Wei Hui-ping Tang Shi-feng liu School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina School of Engineering Zhejiang University City CollegeHangzhou 310015ZhejiangChina

The oxygen content of metal powder is decisive for the recyclability of *** research on the effect of oxygen content on powder properties and material formability has practical significance for economical production with additive manufacturing while preventing the waste of ***,we deliberately oxidized the powder by baking at high temperature to increase the oxygen content in the powder and gave the calculation method of the oxygen content in the powder oxidation *** majority of oxygen element was found in the oxide particles in the powder and the oxide flm on the powder surface,which did affect the flowability of the *** is worth noting that the increase in the oxygen content does not change the phase of H13 steel,but it can promote the molten pool flow and obtain a smoother *** increase in the oxygen content in the powder is not the decisive factor for the formability and defects of the printed *** is the combined effect of the powder deformation,the increase in the oxygen content,and the impurity pollution after repeated use,which leads to the limitation of repeated utilization of the powder.

关键词： Additive manufacturing Electron beam melting H13 steel powder-Powder oxidation

Inverting the rock mass P-wave velocity field ahead of deep buried tunnel face while borehole drilling

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International Journal of Mining Science and Technology 2024年第5期34卷 681-697页

作者： liu liu Shaojun Li Minzong Zheng Dong Wang Minghao Chen Junbo Zhou tingzhou yan Zhenming Shi State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China China Railway Eryuan Engineering Group CO. LTD.Chengdu 610031China Department of Hydraulic and Hydropower Engineering Tsinghua UniversityBeijing 100084China Hubei Communications Planning and Design Institute CO. LTD.Wuhan 430051China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China

Imaging the wave velocity field surrounding a borehole while drilling is a promising and urgently needed approach for extending the exploration range of the borehole *** paper develops a drilling process detection(DPD)system consisting of a multifunctional sensor and a pilot geophone installed at the top of the drilling rod,geophones at the tunnel face,a laser rangefinder,and an onsite computer.A weighted adjoint-state first arrival travel time tomography method is used to invert the P-wave velocity field of rock mass while borehole drilling.A field experiment in the ongoing construction of a deep buried tunnel in southwestern China demonstrated the DPD system and the tomography ***-frequency analysis of typical borehole drilling detection data shows that the impact drilling source is a pulse-like seismic exploration wavelet.A velocity field of the rock mass in a triangular area defined by the borehole trajectory and geophone receiving line can be *** the borehole core and optical image validate the inverted P-wave velocity field.A numerical simulation of a checkerboard benchmark model is used to test the tomography *** rapid convergence of the misfits and consistent agreement between the inverted and observed travel times validate the P-wave velocity imaging.

关键词： Deep buried tunnel Wave velocity field Borehole drilling Tomography Rock mass

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Constructing multifunctional deep-blue emitters with weak charge transfer excited state for high-performance non-doped blue OLEDs and single-emissive-layer hybrid white OLEDs

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Chinese Chemical Letters 2024年第10期35卷 201-205页

作者： Hui liu Xiangyang Tang Zhuang Cheng Yin Hu yan yan yangze Xu Zihan Su Futong liu Ping Lu State Key Laboratory of Supramolecular Structure and Materials Department of Chemistry Jilin University Sichuan Province Key Laboratory of Information Materials and Devices Application College of Optoelectronic Engineering Chengdu University of Information Technology

Deep-blue emitter with high photoluminescence efficiency （PLQY） is highly desirable in ultra-high definition displays and white solid-state *** this work,two deep-blue phenanthro[9,10]imidazole derivatives,PPIS and PPPIS,with hot exciton property are successfully *** to PPIS,the embedded phenyl bridge in PPPIS is able to effectively increase the overlap of frontier molecular *** consequence,PPPIS shows higher oscillator strength and significantly enhanced *** also achieves better electroluminescence performance in non-doped device,showing deep-blue emission with Commission International de l’Eclairage （CIE） coordinates of （0.153,0.087） and the maximum external quantum efficiency (EQEmax) of 8.5%with minuscule efficiency ***,when PPPIS serves as the host for phosphor PO-01,high-efficiency orange phosphorescent device is obtained with high EQEmaxof 29.8%and negligible efficiency roll-off at 1000 cd/***,efficient single-emissive-layer white device is assembled via utilizing PPPIS as a blue emitter as well as the host for PO-01 simultaneously,providing warm-white emission with CIE coordinates of （0.429,0.433） at 1000 cd/m2,the forward-viewing EQEmaxof 27.2%and maximum power efficiency (PEmax) of 80.1 lm/W,*** studies can establish a viable design strategy for deep-blue emitters in high-performance non-doped blue OLEDs and hybrid WOLEDs.

关键词： Deep-blue emitters Host Hot exciton Phenanthroimidazole Single-emissive-layer white device

Sparse antenna array design methodologies:A review

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Journal of Electronic Science and Technology 2024年第3期22卷 1-15页

作者： Pan Wu yan-Hui liu Zhi-Qin Zhao Qing-Huo liu School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Eastern Institute of Technology Ningbo315200China

Designing a sparse array with reduced transmit/receive modules(TRMs)is vital for some applications where the antenna system’s size,weight,allowed operating space,and cost are *** arrays exhibit distinct architectures,roughly classified into three categories:Thinned arrays,nonuniformly spaced arrays,and clustered *** numerous advanced synthesis methods have been presented for the three types of sparse arrays in recent years,a comprehensive review of the latest development in sparse array synthesis is *** work aims to fill this gap by thoroughly summarizing these *** study includes synthesis examples to facilitate a comparative analysis of different techniques in terms of both accuracy and ***,this review is intended to assist researchers and engineers in related fields,offering a clear understanding of the development and distinctions among sparse array synthesis techniques.

关键词： Clustered array Nonuniformly spaced array Sparse antenna array Synthesis method Thinned array

3D printed silicon-based micro-lattices with ultrahigh areal/gravimetric capacities and robust structural stability for lithium-ion batteries

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Nano Research 2024年第4期17卷 2693-2703页

作者： Jie Fu Dong Wang yan Li Xianzheng liu Rui Zhang Zhiyuan liu Pengdong liu Lijuan Zhang Xuefei Li Guangwu Wen School of Materials Science and Engineering Shandong University of TechnologyZibo 255000China Shandong Si-Nano Materials Technology Co. Ltd.Zibo 255000China

Nanostructured silicon anodes have shown extraordinary lithium storage properties for lithium-ion batteries(LIBs)but are usually achieved at low areal loadings(<1.5 mg·cm^(-2))with low areal *** sound electrochemical... 详细信息

Nanostructured silicon anodes have shown extraordinary lithium storage properties for lithium-ion batteries(LIBs)but are usually achieved at low areal loadings(ting on constructing high mass loading silicon anode for practical high energy-density LIBs.

关键词： silicon anode areal capacity three-dimensional(3D)printing lithium-ion batteries

Highly selective photocatalytic oxidation of methane to methyl hydroperoxide

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Nano Research 2024年第4期17卷 2473-2480页

作者： Chunling Bo Li Zhang Xiaolong liu Huaiqiu Chang Yingxue Sun Xinyi Zhang ting Tan Lingyu Piao National Center for Nanoscience and Technology Beijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

Partial oxidation of methane into primary oxidation products with high value remains a *** this work,photocatalytic oxidation of methane(CH_(4))with high methyl hydroperoxide(CH_(3)OOH)selectivity is achieved using pure titanium oxide(TiO_(2))without any cocatalyst at room temperature and atmospheric *** CH_(3)OOH production rate can reach up to 2050±88μmol·g^(-1)·h^(-1) at pH≈7.0 with 100%selectivity in the liquid *** stable reaction cycle can reach more than 30 *** low-cost system achieves superior CH_(4) conversion activity and selectivity compared with similar *** energy of hydrogen peroxide(H_(2)O_(2))to adsorbed hydroperoxyl radical(^(*)OOH)has a significantly lower reaction energy than conversion to adsorbed hydroxyl radical(*OH)on the(210)surface of the TiO_(2).The^(*)OOH preferentially combines with methyl radical(·CH_(3))to form the most energetically favorable CH_(3)*** mild oxidative environment of this system prevents the reduction of CH_(3)OOH to CH_(3)OH or over-oxidation of CH_(4),which ensures the final CH_(3)OOH with high selectivity and *** work provided a low-cost but highly efficient method to achieve partial oxidation with superior selectivity,i.e.,to convert CH_(4) into high-value chemicals.

关键词： photocatalytic methane oxidation methyl hydroperoxide titanium oxide

Composition optimization and performance prediction for ultra-stable water-based aerosol based on thermodynamic entropy theory

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Defence Technology（防务技术） 2024年第3期33卷 437-446页

作者： tingting Kang Canjun yan Xinying Zhao Jingru Zhao Zixin liu Chenggong Ju Xinyue Zhang Yun Zhang yan Wu College of Chemical Engineering and Materials Science Tianjin University of Science and TechnologyNo.29 13th AvenueEconomic and Technologic Development ZoneTianjin 300457China Tianjin Key Laboratory of Brine Chemical Engineering and Resource Eco-utilization Tianjin University of Science and TechnologyTianjin 300457China College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China

Water-based aerosol is widely used as an effective strategy in electro-optical countermeasure on the battlefield used to the preponderance of high efficiency,low cost and ***,the stability of the water-based aerosol is always unsatisfactory due to the rapid evaporation and sedimentation of the aerosol *** efforts have been devoted to improve the stability of water-based aerosol by using additives with different composition and ***,the lack of the criterion and principle for screening the effective additives results in excessive experimental time consumption and *** the stabilization time of the aerosol is still only 30 min,which could not meet the requirements of the perdurable ***,to improve the stability of water-based aerosol and optimize the complex formulation efficiently,a theoretical calculation method based on thermodynamic entropy theory is *** the factors that influence the shielding effect,including polyol,stabilizer,propellant,water and cosolvent,are considered within *** ultra-stable water-based aerosol with long duration over 120 min is obtained with the optimal fogging agent composition,providing enough time for fighting the electro-optic *** design guideline for choosing the additives with high phase transition temperature and low phase transition enthalpy is also proposed,which greatly improves the total entropy change and reduce the absolute entropy change of the aerosol cooling process,and gives rise to an enhanced stability of the water-based *** theoretical calculation methodology contributes to an abstemious time and space for sieving the water-based aerosol with desirable performance and stability,and provides the powerful guarantee to the homeland security.

关键词： Ultra-stable Water-based aerosol Thermodynamic entropy Composition optimization Performance prediction

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A Strong,Tough,and Self-Healing Strengthening Thioctic Acid-based Elastomer for Highly Reliable Flexible Strain Sensor

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Chinese Journal of Polymer Science 2024年第10期42卷 1610-1618,I0016页

作者： Xin-Yu Chen Yu-Bing Fu Xue-Ling yan Lan liu School of Materials Science and Engineering Key Lab of Guangdong Province for High Property and Functional Polymer MaterialsSouth China University of TechnologyGuangzhou510641China

Elastomers with high strength and toughness,excellent self-healing properties,and biocompatibility have broad application prospects in wearable electronics and other fields,but preparing it remains a *** this work,we propose a highly adaptable strategy by introducing the small molecule crosslinking agent of triethanolamine(TEA)to the poly(thioctic acid)(PTA)chains and preparing the PAx Ey elastomers using a simple synthesis *** strategy stabilizes the PTA chains by constructing multiple non-covalent cross-linked dynamic networks,endowing materials with excellent strength and toughness(tensile strength of 288 kPa,toughness of 278.2 kJ/m3),admirable self-healing properties(self-healing efficiency of 121.6%within 7 h at 70℃),and good *** PAx Ey elastomers can also be combined with MWNTs to become flexible strain sensors,which can be used to monitor human joint movements with high sensitivity,repeatable responses,and stability.

关键词： Thioctic acid Ion clusters Multiple dynamic networks Self-healing strengthening Flexible strain sensor

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Predicting submerged vegetation drag with a machine learning-based method

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Journal of Hydrodynamics 2024年第3期36卷 534-545页

作者： Meng-yang liu Hong-wu Tang Sai-yu Yuan Jing yan College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(H^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： Drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array

Seasonal response of nitrogen exchange fluxes to crab disturbance at sediment-water interface in coastal tidal wetlands

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Water Science and Engineering 2024年第2期17卷 129-138页

作者： Guo-fen Hua Shang-qing liu Xiang-dong liu Jin-li Li Yue Fang Wen-ting Xie Xiang Xu College of Water Conservancy and Hydroelectric Power Hohai UniversityNanjing 210098China College of Renewable Energy Hohai UniversityNanjing 210098China

Coastal wetlands are hotspots for nitrogen(N)cycling,and crab burrowing is known to transform N in intertidal marsh ***,the underlying mechanisms remain *** study conducted field experiments and used indoor control test devices to investigate the seasonal response of nitrogen to crab disturbance at the sediment-water interface in coastal tidal flat *** results showed that crab disturbance exhibited significant seasonality with large seasonal differences in cave density and *** to crab disturbance,nitrogen fuxes at the sediment-water interface were much greater in the box with crabs than in the box without *** summer,NH-N showed a positive flux from the sediment to the overlying water,but NO2-N and NOg-N showed positive fluxes from the sediment to the overlying water only in early *** winter,NH-N showed a positive flux from the sediment to the overlying water,but NO-N and NO,-N both exhibited positive and negative *** results indicated that the presence of crab burrows can cause the aerobic layer to move downward by approximately 8-15 cm in summer and directly promote nitrification at the sediment surface.

关键词： Coastal tidal flat wetland Crab disturbance Nitrogen flux Nitrification Denitrification Sediment-water interface