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Recent Advances in Fibrous Materials for Hydroelectricity Generation

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Nano-Micro Letters 2025年第2期17卷 109-133页

作者： Can Ge Duo Xu xiao feng Xing yang Zheheng Song Yuhang Song Jingyu Chen Yingcun liu Chong Gao Yong Du Zhe Sun Weilin Xu jian Fang College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123People’s Republic of China National Engineering Laboratory for Modern Silk Soochow UniversitySuzhou 215123People’s Republic of China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200People’s Republic of China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123People’s Republic of China Department of Electrical and Computer Engineering University of MassachusettsAmherstMA 01003USA Department of Materials Imperial College LondonSouth Kensington CampusLondon SW72AZUK College of Textile Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China School of Materials Science and Engineering Shanghai Institute of Technology100 Haiquan RoadShanghai 201418People’s Republic of China

Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable *** generation from ubiquitous and spontaneous phase transitions between liquid and gaseous water has been considered a promising strategy for mitigating the energy *** materials with unique flexibility,processability,multifunctionality,and practicability have been widely applied for fibrous materials-based hydroelectricity generation(FHG).In this review,the power generation mechanisms,design principles,and electricity enhancement factors of FHG are first ***,the fabrication strategies and characteristics of varied constructions including 1D fiber,1D yarn,2D fabric,2D membrane,3D fibrous framework,and 3D fibrous gel are ***,the advanced functions of FHG during water harvesting,proton dissociation,ion separation,and charge accumulation processes are analyzed in ***,the potential applications including power supply,energy storage,electrical sensor,and information expression are also ***,some existing challenges are considered and prospects for future development are sincerely proposed.

关键词： Hydroelectricity Fibrous material Streaming potential Ion diffusion

Microstructure and mechanical properties of reaction-bonded B_(4)C–SiC composites

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International Journal of Minerals,Metallurgy and Materials 2021年第11期28卷 1828-1835页

作者： Rong-zhen liu wen-wei gu Yu yang Yuan Lu hong-bin Tan jian-feng yang State Key Laboratory of Materials Processing and Die&Mould Technology School of Material Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Environment-Friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang 621010China

Reaction-bonded B_(4)C–SiC composites are highly promising materials for numerous advanced technological ***,their microstructure evolution mechanism remains ***,B_(4)C–SiC composites were fabricated through the Si-melt infiltration *** influences of the sintering time and the B_(4)C content on the mechanical properties,microstructure,and phase evolution were investigated.X-ray diffraction results showed the presence of SiC,boron silicon,boron silicon carbide,and boron *** electron microscopy results showed that with the increase in the boron carbide content,the Si content decreased and the unreacted B_(4)C amount increased when the sintering temperature reached 1650°C and the sintering time reached 1 *** unreacted B_(4)C diminished with increasing sintering time and temperature when B_(4)C content was lower than 35wt%.Further microstructure analysis showed a transition area between B_(4)C and Si,with the C content marginally higher than in the Si *** indicates that after the silicon infiltration,the diffusion mechanism was the primary sintering mechanism of the *** the diffusion process progressed,the hardness *** maximum values of the Vickers hardness,flexural strength,and fracture toughness of the reaction-bonded B_(4)C–SiC ceramic composite with 12wt%B_(4)C content sintered at 1600°C for 0.5 h were about HV 2400,330 MPa,and 5.2 MPa·m^(0.5),respectively.

关键词： reaction sintering B_(4)C-SiC composites mechanical properties microstructural characterization microstructure evolution mechanism

Fault Feature Extraction of Diesel Engine Based on Bispectrum Image Fractal Dimension

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Chinese Journal of Mechanical Engineering 2018年第2期31卷 216-226页

作者： jian Zhang Chang-wen liu feng-Rong Bi xiao-Bo Bi xiao yang State Key Laboratory of Engines Tianjin University

Fault feature extraction has a positive effect on accurate diagnosis of diesel engine. Currently, studies of fault feature extraction have focused on the time domain or the frequency domain of signals. However, early fault signals are mostly weak energy signals, and time domain or frequency domain features will be overwhelmed by strong back?ground noise. In order consistent features to be extracted that accurately represent the state of the engine, bispectrum estimation is used to analyze the nonlinearity, non?Gaussianity and quadratic phase coupling(QPC) information of the engine vibration signals under different conditions. Digital image processing and fractal theory is used to extract the fractal features of the bispectrum pictures. The outcomes demonstrate that the diesel engine vibration signal bispectrum under different working conditions shows an obvious differences and the most complicated bispectrum is in the normal state. The fractal dimension of various invalid signs is novel and diverse fractal parameters were utilized to separate and characterize them. The value of the fractal dimension is consistent with the non?Gaussian intensity of the signal, so it can be used as an eigenvalue of fault diagnosis, and also be used as a non?Gaussian signal strength indicator. Consequently, a symptomatic approach in view of the hypothetical outcome is inferred and checked by the examination of vibration signals from the diesel motor. The proposed research provides the basis for on?line monitoring and diagnosis of valve train faults.

关键词： Engine fault diagnosis Bispectrum image processing Fractal Signal processing

Estimation of vegetation biophysical parameters by remote sensing using radial basis function neural network

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第6期8卷 883-895页

作者： yang xiao-hua HUANG Jing-feng WANG jian-wen WANG Xiu-zhen liu Zhan-yu Institute of Agricultural Remote Sensing ＆ Information Application Zhejiang University Hangzhou 310029 China Key Laboratory of Agricultural Remote Sensing ＆ Information System Hangzhou 310029 China Communication Training Base of General Staff Headquarters Beijing 102400 China Zhejiang Meteorological Institute Hangzhou 310004 China

Hyperspectral reflectance (350~2500 nm) data were recorded at two different sites of rice in two experiment fields including two cultivars, and three levels of nitrogen (N) application. Twenty-five Vegetation Indices (VIs) were used to predict the rice agronomic parameters including Leaf Area Index (LAI, m2 green leaf/m2 soil) and Green Leaf Chlorophyll Density (GLCD, mg chlorophyll/m2 soil) by the traditional regression models and Radial Basis Function Neural Network (RBF). RBF emerged as a variant of Artificial Neural Networks (ANNs) in the late 1980’s. A large variety of training algorithms has been tested for training RBF networks. In this study, Original RBF (ORBF), Gradient Descent RBF (GDRBF), and Generalized Regression Neural Network (GRNN) were employed. Results showed that green waveband Normalized Difference Vegetation Index (NDVIgreen) and TCARI/OSAVI have the best prediction power for LAI by exponent model and ORBF respectively, and that TCARI/OSAVI has the best prediction power for GLCD by exponent model and GDRBF. The best performances of RBF are compared with the traditional models, showing that the relationship between VIs and agronomic variables are further improved when RBF is used. Compared with the best traditional models, ORBF using TCARI/OSAVI improves the prediction power for LAI by lowering the Root Mean Square Error (RMSE) for 0.1119, and GDRBF using TCARI/OSAVI improves the prediction power for GLCD by lowering the RMSE for 26.7853. It is concluded that RBF provides a useful exploratory and predictive tool when applied to the sensitive VIs.

关键词： Artificial neural network (ANN) Radial basis function (RBF) Remote sensing Rice Vegetation index (VI)

Crystal Structure of 4-(4-chlorophenyl)-7,7-dimethyl-2,5- dioxo-1,2,3,4,5,6,7,8-octahydroquinoline

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Chinese Journal of Structural Chemistry 2001年第6期20卷 459-461页

作者： TU Shu-jiang ZHOU jian-feng GAO Yuan liu xiao-hong Department of Chemistry Xuzhou Normal University Department of Chemistry Huaiyin Teacher College Department of Chemistry Shenzhen University

The crystal structure of the title compound (C17H18ClNO2) has been determined by single-crystal X-ray diffraction. The crystal is monoclinic with space group C2/c, a=23.677(5), b=9.5333(2), c=14.027(3)? b=98.06(3), V=313.5(1)?, Mr=303.77, Z=8, Dc=1.287g/cm3, l=0.71073, m(MoKa)=0.247mm-1, F(000)=1280. The structure was refined to R=0.0600, wR=0.1959 for 2020 reflections with I>2s(I). X-ray analysis reveals that the dihedral angle between plane 1 [C(1)~C(6)] and plane 2 [N(1), C(10), C(11), C(7)] is 78.8(1) , between plane 2 and plane 3 [C(10), C(11), C(12), C(13), C(15)] is 3.95(7) .

关键词： quinoline synthesis crystal structure

Comparison between direct repair and humana cellular nerve allografting during contralateral C7 transfer to the upper trunk for restoration of shoulder abduction and elbow flexion

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Neural Regeneration Research 2019年第12期14卷 2132-2140页

作者： Liang Li wen-Ting He Ben-Gang Qin xiao-Lin liu jian-Tao yang Li-Qiang gu Department of Orthopedic Trauma and Microsurgery the First Affiliated Hospital of Sun Yat-sen University

Direct coaptation of contralateral C7 to the upper trunk could avoid the interposition of nerve grafts. We have successfully shortened the gap and graft lengths, and even achieved direct coaptation. However, direct repair can only be performed in some selected cases, and partial procedures still require autografts, which are the gold standard for repairing neurologic defects. As symptoms often occur after autografting, human acellular nerve allografts have been used to avoid concomitant symptoms. This study investigated the quality of shoulder abduction and elbow flexion following direct repair and acellular allografting to evaluate issues requiring attention for brachial plexus injury repair. Fifty-one brachial plexus injury patients in the surgical database were eligible for this retrospective study. Patients were divided into two groups according to different surgical methods. Direct repair was performed in 27 patients, while acellular nerve allografts were used to bridge the gap between the contralateral C7 nerve root and upper trunk in 24 patients. The length of the harvested contralateral C7 nerve root was measured intraoperatively. Deltoid and biceps muscle strength, and degrees of shoulder abduction and elbow flexion were examined according to the British Medical Research Council scoring system;meaningful recovery was defined as M3–M5. Lengths of anterior and posterior divisions of the contralateral C7 in the direct repair group were 7.64 ± 0.69 mm and 7.55 ± 0.69 mm, respectively, and in the acellular nerve allografts group were 6.46 ± 0.58 mm and 6.43 ± 0.59 mm, respectively. After a minimum of 4-year follow-up, meaningful recoveries of deltoid and biceps muscles in the direct repair group were 88.89% and 85.19%, respectively, while they were 70.83% and 66.67% in the acellular nerve allografts group. Time to C5/C6 reinnervation was shorter in the direct repair group compared with the acellular nerve allografts group. Direct repair facilitated the restorati

关键词： nerve regeneration contralateral C7 nerve root transfer nerve graft brachial plexus avulsion injury direct repair human acellular nerve allograft shoulder function elbow function nerve transfer phrenic nerve accessary nerve neural regeneration

Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope

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Water Science and Engineering 2024年第2期17卷 197-208页

作者： Wei He Si-yuan feng jian Zhang hong-wu Tang yang xiao Sheng Chen Chun-sheng liu College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Collaborative Innovation Center on Water Safety and Water Science Hohai UniversityNanjing 210098China

Lateral intakes are common in *** pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division *** hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be ***,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be ***,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side *** flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel *** study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this *** average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank *** a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical *** inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope *** results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains.

关键词： Lateral withdrawal Hydrodynamic characteristics Particle tracking Inclined river slope Bottom elevation of intake OpenFOAM

Resonant multiple wave solutions to some integrable soliton equations

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Chinese Physics B 2019年第11期28卷 92-98页

作者： jian-Gen liu xiao-Jun yang Yi-Ying feng School of Mathematics China University of Mining and TechnologyXuzhou 221116China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 221116China

To transform the exponential traveling wave solutions to bilinear differential equations, a sufficient and necessary condition is proposed. Motivated by the condition, we extend the results to the(2+1)-dimensional Kadomtsev–Petviashvili(KP) equation, the(3+1)-dimensional generalized Kadomtsev–Petviashvili(g-KP) equation, and the B-type Kadomtsev–Petviashvili(BKP) equation. Aa a result, we obtain some new resonant multiple wave solutions through the parameterization for wave numbers and frequencies via some linear combinations of exponential traveling waves. Finally, these new resonant type solutions can be displayed in graphs to illustrate the resonant behaviors of multiple wave solutions.

关键词： linear superposition principle resonant multiple wave solutions (2+1)-dimensional Kadomtsev–Petviashvili(KP) equation (3+1)-dimensional g-KP and BKP equations

Simulation and photoelectron track reconstruction of soft X-ray polarimeter

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Nuclear Science and Techniques 2021年第7期32卷 1-10页

作者： Xue-feng Huang hong-Bang liu Jin Zhang Bo Huang wen-Jin Xie Huan-Bo feng Xi-Chen Cai Xi-wen liu Zi-Li Li jian-Yu gu Qian liu Jin Li En-Wei Liang guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China PLAC Key Laboratory of Quark and Lepton Physics(MOE)Central China Normal UniversityWuhan 430079China School of Physical Science University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

The soft X-ray polarimeter(SXP)is a detector with a wide energy range,large area,and large field of view.A SXP will be mounted on the Chinese Space Station and will mainly focus on detecting the polarization of transient soft X-ray(2–10 keV)sources,especially gamma-ray bursts(GRBs).In this work,a polarimeter detector unit is taken as an example,and Geant4 and Garfield++software are used to simulate the detection efficiency and track *** improved track reconstruction algorithm is proposed and used to reconstruct two-dimensional images of the *** this method,the initial emission angle of photoelectrons is reconstructed from the initial part of the track by shortening or extending the initial part of the track until the remaining track is straight,and the number of pixels is within an adjustable *** modulation factor of the photoelectronic tracks after reconstruction reaches approximately 57%in the photon energy range of 7–10 keV.

关键词： X-ray Polarimetry Track reconstruction algorithm