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Characteristics and efficiency of a new vibrating screen with a swing trace

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Particuology 2013年第5期11卷 601-606页

作者： Jianzhang Xiao xin tong School of Mechanical Engineering and Automation Huaqiao University

A new vibration type and motion characteristics were proposed according to the principle of manual sie- ving. A mechanical model of the new motion was established and the characteristics of the new vibrating screen were analyzed to establish its equation of motion by using the vibration theory, to include as tech- nological parameters, amplitude, movement velocity, and throwing index through theoretical calculation. The efficiency of particle screening was studied at different values of frequency and swing declination angle. The discrete element method （DEM） was used to simulate the screening with the swing trace. The functional relationship between screening efficiency and the parameters was fitted with the least square method. The results show that high frequency and large swing angle are suitable for small particles, while small values are suitable for particles close to the aperture size. Compared to the linear vibration trace, both screening efficiency and processing capacity were effectively improved.

关键词： Motion characteristicSwing traceScreening efficiencySimulation

Broadband and efficient second harmonic generation in LiNbO_(3)-LiTaO_(3) composite ridge waveguides at telecom-band

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Chinese Physics B 2021年第1期30卷 256-261页

作者： xin-tong Zhang Department of Optics and Optical Engineering University of Science and Technology of ChinaHefei 230026China

Broadband nonlinear frequency conversions of optical waves are widely employed in multiple areas of optics and photonics. However, the broadening of conversion bandwidth is often at a cost of reduction in efficiency, which may induce a limitation on practical applications. Here we theoretically propose a novel design of LiNbO_(3) ridge waveguides on LiTaO_(3) substrates which can be used for efficient and broadband second harmonic generation. Through group velocity engineering of the ridge waveguides, acceptance bandwidth over 20 nm with a high conversion efficiency of > 25%W^(-1)·cm^(-2) is achieved at telecom-band.

关键词： second harmonic generation lithium niobate ridge waveguide dispersion manipulation

Fractionation of Polyolefin Elastomer by a Modified SSA Technique

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Chinese Journal of Polymer Science 2022年第10期40卷 1252-1258,I0010页

作者： xin-tong Zhao Yong-Feng Men State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Schoolof Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

As an important part of semicrystalline polymer materials,polyolefin elastomers are widely used,and the in-depth analysis of their molecular chain structure information is of great significance to promote their rapid *** show in this work an effort in characterizing a commercial polyolefin elastomer of ethylene/1-octene copolymer by a modified successive self-nucleation and annealing(SSA)technique.A small amount of linear polyethylene was blended with the ethylene/1-octene copolymer serving as nucleation agent during *** turned out that a tiny fraction of linear polyethylene can significantly promote the crystallization of the copolymer during cooling from different annealing temperatures and increase the melting temperature of the fractions so that providing apparent methylene sequence length much closer to the real value than obtained by traditional SSA technique.

关键词： Polyolefin elastomer Ethylene-co-octene Thermal fractionation SSA Micro structure

Propagation Characteristics of Exponential-Cosine Gaussian Vortex Beams

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Chinese Physics Letters 2021年第8期38卷 43-49页

作者： xin tong Daomu Zhao Zhejiang Province Key Laboratory of Quantum Technology and Device Department of PhysicsZhejiang UniversityHangzhou 310027China

We propose a controllable exponential-Cosine Gaussian vortex(ECGV)beam,which can evolve into the different beam profiles with three parameters:distance modulation factor(DMF),split modulation factor(SMF)and rotation modulation factor(RMF).When SMF is 0,the ECGV beam appears as a perfect single-ring vortex beam and the ring radius can be adjusted by the *** deduce from mathematics and give the reason for the single-ring *** SMF is not 0,the beam splits ***,SMF and RMF control the number,distance and rotation angle of the split,*** experiments verify the correctness of the theory.

关键词： theory rotation vortex

Semantic segmentation-assisted instance feature fusion for multi-level 3D part instance segmentation

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Computational Visual Media 2023年第4期9卷 699-715页

作者： Chun-Yu Sun xin tong Yang Liu Institute for Advanced Study Tsinghua UniversityBeijing 100084China Microsoft Research Asia Beijing 100080China

Recognizing 3D part instances from a 3D point cloud is crucial for 3D structure and scene *** learning-based approaches use semantic segmentation and instance center prediction as training tasks and fail to further exploit the inherent relationship between shape semantics and part *** this paper,we present a new method for 3D part instance *** method exploits semantic segmentation to fuse nonlocal instance features,such as center prediction,and further enhances the fusion scheme in a multi-and cross-level *** also propose a semantic region center prediction task to train and leverage the prediction results to improve the clustering of instance *** method outperforms existing methods with a large-margin improvement in the PartNet *** also demonstrate that our feature fusion scheme can be applied to other existing methods to improve their performance in indoor scene instance segmentation tasks.

关键词： 3D part instance segmentation feature fusion 3D deep learning

Particle stratification and penetration of a linear vibrating screen by the discrete element method

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International Journal of Mining Science and Technology 2012年第3期22卷 357-362页

作者： Xiao Jianzhang tong xin School of Mechanical Engineering and Automation Huaqiao University Xiamen 361021 China

A simulation of stratification and penetration was performed over a range of structural parameters that included screen width, aperture size, inclination angle, and wire diameter. The discrete element method （DEM） was used for the simulations. The terms stratification and penetration are defined and the change in fine panicle concentration is discussed. Mathematical models relating fine particle ratio to time are established using the least squares method. The effect of structural parameters on fine panicle ratio is analyzed. Stratification and penetration rate are discussed by considering the time derivative of the fine panicle ratio. The conclusions are： an increase in inclination or wire diameter has a positive effect on par- ticle stratifying; The optimal screen width is 40 mm for panicle stratification; The inclination angle has a negative effect on the penetration; The effect of wire diameter and screen width on the penetration rate is negligible.

关键词： Fine particle ratioStratificationPenetrationStructural parameter

Reaction Kinetics of Trans-Sobrerol and 8-p-Menthen-1,2-diol with Hydroxyl Radical in Aqueous Solution： A Combined Experimental and Theoretical Study

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Chinese Journal of Chemical Physics 2015年第3期28卷 308-314,I0001,I0002页

作者： Yan Long xin tong tong-mei Ma Li-ming Wang School of Chemistry & Chemical Engineering South China University of Technology Guangzhou 510640 China Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control South China University of Technology Guangzhou 510006 China

Trans-sobrerol （Sob） and 8-p-menthen-1,2-diol （Limo-diol） are the primary products in the atmospheric oxidation of α-pinene and limonene, respectively. Because of their low volatility, they associate more likely to the liquid particles in the atmosphere, where they are subject to the aqueous phase oxidation by the atmospheric oxidants. In this work, through experimental and theoretical study, we first provide the rate constants of Sob and Limo-diol reacting with hydroxyl radical （.OH） in aqueous solution at room temperature of 3044-3 K and 1 atm pressure, which are （3.05±0.5）×10 9 and （4.57±0.2）×10 9 L/（mol.s）, respectively. Quantum chemistry calculations have also been employed to demonstrate the solvent effect on the rate constants in aqueous phase and the calculated results agree well with the measurements. Some reaction products have been identified based on liquid chromatography combined with mass spectroscopy and theoretical calculations.

关键词： Unsaturated alcohols Hydroxyl radical Aqueous-phase reaction Kinetic Theoretical calculations

Influence of Carbon Nanofiber Addition on Mechanical Properties and Crystallization Behavior of Polypropylene

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Journal of Materials Science & Technology 2005年第5期21卷 686-690页

作者： xin tong Yong CHEN Huiming CHENG Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China Materials Science & Engineering College Shenyang Ligong University Shenyang 110168 China

Carbon nanofiber （CNF）-reinforced polypropylene （CNF/PP） composites with different CNF contents were prepared by melt mixing, and the mechanical properties and crystallization behavior of the CNF/PP composites obtained were investigated. It was found that the tensile modulus of the composites was increased with the addition of CNFs, but their elongation at break and fracture strain energy were decreased, while the tensile strength of the composites was firstly increased and then decreased due to the agglomeration of CNFs at higher loading. Nonisothermal crystallization analysis showed that the CNFs played a role as nucleating agent in PP matrix, which led to increment in the crystallization rate and the degree of crystallinity of PP. Moreover, X-ray diffraction studies showed that the CNFs incorporated in the PP matrix favored the growth of （040）-oriented PP crystals. With the increase in the CNF content, the nucleating and orientation roles of the CNFs were obviously enhanced.

关键词： Carbon nanofibers Composites Mechanical properties Crystallization behavior

Modeling screening efficiency with vibrational parameters based on DEM 3D simulation

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Mining Science and Technology 2010年第4期20卷 615-620页

作者： CHEN Yanhua tong xin School of Mechanical Engineering and Automation Huaqiao UniversityQuanzhou 362021China

The efficiency of particle screening was studied over a range of vibrational parameters including amplitude, frequency and vibrational direction. The Discrete Element Method (DEM) was used to simulate the screening process. A functional relationship between efficiency and the parameters, both singly and combined, is established. The function is a complicated exponential. Optimal amplitude and frequency values are smaller for particles near the mesh and larger for other particles. The optimum vibration angle is 45° for nearly all kinds of particles. A transverse velocity, V⊥, was defined and V⊥=0.2 m/s was identified to be the most efficient operating point by both simulation and experimental observation. Comparison of these results with those reported by others is included.

关键词： modeling screening efficiency discrete element method simulations