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Microsystems & Nanoengineering 2024年第3期10卷 369-379页

作者： Tianyi zhang Peng Zhou Terrence Simon Tianhong cui Department of Mechanical Engineering University of MinnesotaMinneapolisMN 55455USA

The introduction of flows within sessile droplets is highly effective for many lab-on-a-chip chemical and biomedical ***,generating such flows is difficult due to the typically small droplet ***,we present a simple,non-contact strategy to generate internal flows in sessile droplets for enhancing mixing and mass *** flows are driven by actuating a rigid substrate into oscillation with certain amplitude distributions without relying on the resonance of the droplet *** oscillation characteristics and corresponding flow patterns are documented *** indices and mass transfer coefficients of sessile droplets on the substrate surface are measured using optical and electrochemical *** demonstrate complete mixing within the droplets in 1.35 s and increases in mass transfer rates of more than seven times static *** of concept was conducted with experiments of silver nanoparticle synthesis and with heavy metal ion sensing employing the sessile droplet as a microreactor for synthesis and an electrochemical cell for *** degrees of enhancement of synthesis efficiency and detection sensitivity attributed to the internal flows are experimentally documented.

关键词： mixing oscillation synthesis

Multiwavelength Observations of the Infrared Dust Bubble N75 and its Surroundings

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Research in Astronomy and Astrophysics 2024年第4期24卷 262-270页

作者： Quan-Ling cui Chuan-Peng zhang Jun-Jie Wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Science Qiqihar UniversityQiqihar 161006China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China

Infrared dust bubbles play an important role in the study of star formation and the evolution of the interstellar *** this work,we study the infrared dust bubble N75 and the infrared dark cloud G38.93 mainly using the tracers C^(18)O,HCO^(+),HNC and N_(2.H^(+)observed by the 30 m IRAM *** also study the targets using data from large-scale surveys:GLIMPSE,MIPSGAL,GRS,NRAO VLA Sky Survey and Bolocam Galactic Plane *** found that the C^(18)O emission is morphologically similar to the Spitzer IRAC 8.0μm ***1.1 mm cold dust emission of G38.93 shows an elongated structure from southwest to *** ionized gas from G38.93 is surrounded by polycyclic aromatic hydrocarbon emission,which may be excited by radiation from *** found that the identified young stellar objects tend to cluster around G38.93 and are mostly in class II with several class I cases distributed around N75,but no class II *** also found evidence of expanding feedback,which could have triggered star formation.

关键词： ISM:bubbles infrared:ISM galaxies:star formation

Theoretical assessment of discharge effects on the decomposition tendency of C_(6)F_(12.O over metallic surfaces

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High Voltage 2024年第4期9卷 862-869页

作者： Zhaolun cui Yanpeng Hao Shuangshuang Tian Xiaoxing zhang Yashuang Zheng School of Electric Power Engineering South China University of TechnologyGuangzhouChina State Key Laboratory of Power Transmission Equipment Technology(Chongqing University) ChongqingChina School of Electrical and Electronic Engineering Hubei University of TechnologyWuhanChina

C_(6)F_(12.O is proposed to be one potential eco-friendly insulation gas to replace ***,the assessment of its decomposition properties and the compatibility with metal electrodes in discharge faults is still challenging,which greatly hinders the development of its insulation and arc-extinction ***,a theoretical method is proposed to reasonably address the discharge effects on C_(6)F_(12.O decomposition over typical Cu and Al electrodes at atomic *** results show that both the external electric field and the excess electrons could affect the activation of C_(6)F_(12.O by changing the electron acceptance of C_(6)F_(12.O and the orbital hybridisation during the surface *** metal surfaces,the C-F single bond in adsorbed C_(6)F_(12.O is the weakest position to decompose,and its cleavage could be promoted by the discharge *** the C-F breaking,the C-C cleavage remains unfavourable on Cu(111),but it is significantly promoted on Al(111),indicating a higher corrosion risk on the Al surface via continuous C_(6)F_(12.O *** proposed method as a valid supplement to the experiment reveals the discharge effects and the decomposition tendency of C_(6)F_(12.O on metal electrodes in discharge faults,which broadens the means for insulation gas evaluation.

关键词： corrosion insulation cleavage

A new scheme of climate-vegetation regionalization in the Hengduan Mountains Region

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Science China Earth Sciences 2024年第3期67卷 751-768页

作者： Xueqin zhang Xiaoming XU Xiang LI Peng cui Du ZHENG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences-Higher Education Commission of PakistanIslamabad 45320Pakistan

The Hengduan Mountains Region(HMR) is essential for the future ecological protection, clean energy production,Sichuan-Xizang and Yunnan-Xizang railways, and other major infrastructure projects in China. The distributions of climate and vegetation exhibit significant regional differentiation and vertical zonality due to the rugged longitudinal ranges and gorges and the complex disaster-prone environments in HMR. Therefore, it is urgent to develop the climate-vegetation regionalization in HMR to effectively satisfy the national requirements such as agricultural production and ecological protection, mountain disaster risk prevention, and major project construction. We here develop a new scheme of climate-vegetation regionalization with the latest demarcation outcome of HMR, the ground observation from 12. meteorological stations in HMR and its surrounding areas during 1990–2.19, and the high-precision remote sensing data of land cover types. The new scheme first constructs the regionalization index system, fully considering the extraordinarily complicated geomorphic pattern of mountains and valleys, the scarcity of meteorological observations, and the remarkable differentiation of climate and vegetation in HMR. The system consists of three primary regionalization indices(i.e., days with daily average temperature steady above 10°C, aridity index, and main vegetation types, dividing the temperature zones, moisture regions, and vegetation subregions, respectively) and three auxiliary indices of the accumulated temperature above 10°C, and the temperatures in January and July. Then, the HMR is divided into five temperature zones, 2. moisture regions, and 55 vegetation subregions. Compared with previous regionalization schemes, the new scheme optimizes the climate spatial interpolation model of thin plate smoothing spline suitable for the unique terrain in HMR. Moreover, the disputed division index threshold between different climatic zones(regions) is scientifically clarifi

关键词： Climate-vegetation regionalization Thin plate smoothing spline(TPSS) GeoDetector Stepwise downscaling pane division method Hengduan Mountains Region

Possible Habitats for NH_(3),NH_(2.D,H^(13)CN,HC^(15)N,SO,and C^(18)O in the Initial Conditions of High-mass Star Formation

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Research in Astronomy and Astrophysics 2024年第4期24卷 237-252页

The initial condition of high-mass star formation is a complex area of study because of the high densities(n_(H_(2.)>106cm^(-3))and low temperatures(T_(dust)<18 K)*** such conditions,many molecules become depleted fro... 详细信息

The initial condition of high-mass star formation is a complex area of study because of the high densities(n_(H_(2.)>106cm^(-3))and low temperatures(T_(dust)2.D,H^(13)CN,HC^(15)N,SO,and C^(18)O in eight massive precluster and protocluster clumps G18.17,G18.2.,G2..97N,G2..98,G2..44,G2..97S,G2..38,and *** found that the NH3cores are in good agreement with the 3.5 mm peak emission,but the NH_(3)is much more extended than the 3.5 mm emission *** SO distributions agree well with the 3.5 mm peaks for the evolved star formation stage,but we did not detect any SO emission in the four earliest star formation sources.C^(18)O is a poor tracer in conditions of the cold(■18 K)and dense(■10^(4)cm^(-3))cores,e.g.,the prestellar *** also found that the NH_(2.D cores are mainly located in the temperature range of 13.0-2..0 K,and the NH_(2.D lines may be strongly depleted above 2. K.

关键词： galaxies:star formation techniques:interferometric methods:observational

Occurrence and possible sources of antibiotic resistance genes in seawater of the South China Sea

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Frontiers of Environmental Science & Engineering 2024年第9期18卷 27-38页

作者： Jian Lu Jun Wu cui zhang Jianhua Wang Xia He CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research(YIC)Chinese Academy of Sciences(CAS)Shandong Key Laboratory of Coastal Environmental ProcessesYICCASYantai 264003China Yantai Research Institute Harbin Engineering UniversityYantai 264006China College of Environmental Science and Engineering Guilin University of TechnologyGuilin 541006China

Antibiotic resistance genes(ARGs)might have great effect on ecological security and human *** are important reservoirs that receive tremendous amounts of pollutants ***,information on the proliferation of ARGs in seawater is still *** study performed field sampling to investigate the occurrence and distribution of ARGs in seawater of the South China Sea,which is the deepest and largest sea in *** results showed that the total absolute abundances of ARGs in seawater samples ranged from 2.1×10^(3)to 2.3×10^(4)copies/mL,with an of 5.0×10^(3)copies/mL and a range of 2.2.10^(3)–1.8×10^(4)copies/mL for those with mobile genetic elements(MGEs).Genes resistant to multidrug,aminoglycoside,tetracycline,and fluoroquinolone antibiotics accounted for 77.3%–88.6%of total ARGs in *** and Cyanobacteria represented 32.1%–56.2.and 30.4%–49.5%of microbial community,***_MIT9313 and Clade_la were the prevalent genera in seawater of the South China *** co-occurrence relationship existed among ARGs,MGEs,and *** activities had critical influence on ARGs and *** wastewater,wastewater treatment plant effluent,sewage,aquaculture tailwater,and runoff were determined as the important sources of ARGs in seawater of the South China Sea based on positive matrix factorization analysis.

关键词： The South China Sea Antibiotic resistance genes Mobile genetic element Source apportionment

Experimental study on the effect of flexible joints of a deep-buried tunnel across an active fault under high in-situ stress conditions

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Underground Space 2024年第6期19卷 189-207页

作者： Jiawei zhang Zhen cui Qian Sheng Wanhua Zhao Liang Song State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China School of Civil Engineering and Architecture Wuhan Polytechnic UniversityWuhan 430023China

During dislocation,a tunnel crossing the active fault will be damaged to varying degrees due to its permanent stratum *** previous studies did not consider the influence of the tunnel’s deep burial and the high in-situ stress,so the results were not entirely *** this paper,the necessity of solving the anti-dislocation problem of deep-buried tunnels is systemically *** the model test of tunnels across active faults,the differences in failures between deep-buried tunnels and shallow-buried tunnels were compared,and the dislocation test of deep-buried segmental tunnels was carried out to analyze the external stress change,lining strain,and failure mode of *** results are as follows.(1)The overall deformation of deep-buried and shallow-buried tunnels is both *** failure mode of deep-buried tunnels is primarily characterized by shear and tensile failure,resulting in significant compressive deformation and a larger damaged *** contrast,shallow-buried tunnels mainly experience shear failure,with the tunnel being sheared apart at the fault crossing,leading to more severe damage.(2.After the segmental structure design of the deep-buried tunnel,the‘‘S”deformation pattern is transformed into a‘‘ladder”pattern,and the strain of the tunnel and the peak stress of the external rock mass are reduced;therefore,damages are significantly mitigated.(3)Through the analysis of the distribution of cracks in the tunnel lining,it is found that the tunnel without a segmental structure design has suffered from penetrating failure and that cracks affect the entire *** cracks in a flexible segmental tunnel affect about 66.6%of the entire length of the tunnel,and cracks in a tunnel with a short segmental tunnel only affect about 33.3%of the entire length of the ***,a deep-buried tunnel with a short segmental tunnel can yield a better anti-dislocation effect.(4)By comparing the shallow-buried segmental tunnel in previous

关键词： Tunnel project Crossing active fault High in-situ stress Segmental structure design Flexible joint

Monitoring and detection of steel bridge diseases:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 188-208页

作者： Chuang cui Qinghua zhang Dengke zhang Wulve Lao Lemou Wu Zhenxiong Jiang National Key Laboratory of Bridge Intelligent and Green Construction Southwest Jiaotong UniversityChengdu 610031China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Jiangsu Provincial Transportation Engineering Construction Bureau Nanjing 210004China

Fatigue,corrosion,and bolt loosening are the main causes of structural performance degradation and collapse in steel *** monitoring of steel bridge diseases is a basic premise for ensuring high-quality operation and maintenance of steel *** this regard,a summary and analysis were conducted on the classification of steel bridge diseases,monitoring and detection methods,application statuses,and major *** main causes,research status,and development trends of steel bridge diseases are *** results showed that,for fatigue crack problems,fatigue crack initiation has a small scale,high difficulty in monitoring and detection,few methods,and low *** the cracks grow,the difficulty of monitoring and detection decreases,the number of methods increases,and the accuracy *** crack monitoring and detection are affected by the environmental and vehicular *** corrosion features are evident in steel bridges,and corrosion identification methods and technologies are rapidly *** and detecting corrosion in concealed areas is difficult and requires further improvements in monitoring and detection technologies and their *** and detection methods and supporting equipment for bolt loosening in steel bridges are rapidly *** development of intelligent monitoring and detection technologies and supporting equipment is an important research topic that urgently needs to be addressed for the full-lifecycle operation and maintenance of steel bridges and the sustainable development of bridge *** new intelligent sensing components based on high-performance materials and sensing element design theory to improve the monitoring and detection perception ability is an important development direction for steel bridge monitoring and *** on intelligent monitoring and detection technologies,standardized indicators,and related topics based on intelligent oper

关键词： Steel bridge Diseases Fatigue crack Corrosion Bolt loosening Monitoring and detection

Deep learning CNN-APSO-LSSVM hybrid fusion model for feature optimization and gas-bearing prediction

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Petroleum Science 2024年第4期21卷 2329-2344页

作者： Jiu-Qiang Yang Nian-Tian Lin Kai zhang Yan cui Chao Fu Dong zhang College of Earth Sciences and Engineering Shandong University of Science and Technology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Transportation Institute of Inner Mongolia University Key Laboratory of Gas Hydrate Qingdao Institute of Marine Geology Ministry of Natural Resources

Conventional machine learning(CML) methods have been successfully applied for gas reservoir prediction. Their prediction accuracy largely depends on the quality of the sample data; therefore, feature optimization of the input samples is particularly important. Commonly used feature optimization methods increase the interpretability of gas reservoirs; however, their steps are cumbersome, and the selected features cannot sufficiently guide CML models to mine the intrinsic features of sample data efficiently. In contrast to CML methods, deep learning(DL) methods can directly extract the important features of targets from raw data. Therefore, this study proposes a feature optimization and gas-bearing prediction method based on a hybrid fusion model that combines a convolutional neural network(CNN)and an adaptive particle swarm optimization-least squares support vector machine(APSO-LSSVM). This model adopts an end-to-end algorithm structure to directly extract features from sensitive multicomponent seismic attributes, considerably simplifying the feature optimization. A CNN was used for feature optimization to highlight sensitive gas reservoir information. APSO-LSSVM was used to fully learn the relationship between the features extracted by the CNN to obtain the prediction results. The constructed hybrid fusion model improves gas-bearing prediction accuracy through two processes of feature optimization and intelligent prediction, giving full play to the advantages of DL and CML methods. The prediction results obtained are better than those of a single CNN model or APSO-LSSVM model. In the feature optimization process of multicomponent seismic attribute data, CNN has demonstrated better gas reservoir feature extraction capabilities than commonly used attribute optimization methods. In the prediction process, the APSO-LSSVM model can learn the gas reservoir characteristics better than the LSSVM model and has a higher prediction accuracy. The constructed CNN-APSO-LSSVM mode

关键词： Multicomponent seismic data Deep learning Adaptive particle swarm optimization Convolutional neural network Least squares support vector machine Feature optimization Gas-bearing distribution prediction

Microstructure Characteristics,Texture Evolution and Mechanical Properties of Al-Mg-Si-Mn-xCu Alloys via Extrusion and Heat Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1501-1522页

作者： Zulai Li Yingxing zhang Junlei zhang Xiang Chen Suokun Chen Lujian {2. Shengjie Han College of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China College of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002China National and Local Joint Engineering Laboratory of Advanced Metal Solidification Forming and Equipment Technology Kunming University of Science and TechnologyKunming 650093China Chinalco International Al Application Engineering Co. Ltd.Beijing 100089China

In this work,the impact of extrusion and post-extrusion heat treatment(T6)on the microstructure and mechanical properties of the Al-1.2.g-0.8Si-0.5Mn alloy with different Cu contents(0,0.6,1.3 and 2.0 wt%)was *** characterization showed that all extruded alloys exhibited elongated grain structure with an average grain size of~4.8μ*** dominant texture components were deformation texture(A*,Copper and P texture),while the proportion of random texture initially increased and then decreased with increasing Cu *** T6 treatment,the grain size of the four alloys increased significantly,but the growth trend decreased with increasing Cu content,and the textures transformed into recrystallized textures(Cube,A and Goss texture).Tensile testing revealed that the designed T6 alloys with 2.0%Cu content exhibited an excellent strength-ductility balance,i.e.,a yield strength of 342.9 MPa,an ultimate tensile strength of 42..8 MPa and an elongation of 15.9%.The enhanced strength was mainly attributed to fine grain strengthening,solid solution strengthening and aging strengthening *** superior ductility was due to the pinning effect of fine precipitates and high dislocation accommodation capacity caused by heat treatment.

关键词： Al-Mg-Si-Mn alloy Cu addition Microstructure texture Mechanical Properties