Surface quality prediction model of nano-composite ceramics in ultrasonic vibration-assisted ELID mirror grinding

Bo Zhao,Fan Chen,Xiao-feng Jia,Chong-yang Zhao,Xiao-bo Wang 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.4

Ultrasonic vibration-assisted Electrolytic in-process dressing (ELID) grinding is a highly efficient and highly precise machining method. The surface quality prediction model in ultrasonic vibration-assisted ELID mirror grinding was studied. First, the interaction between grits and workpiece surface was analyzed according to kinematic mechanics, and the surface roughness model was developed. The variations in surface roughness under different parameters was subsequently calculated and analyzed by MATLAB. Results indicate that compared with the ordinary ELID grinding, ultrasonic vibration-assisted ELID grinding is superior, because it has more stable and better surface quality and has an improved range of ductile machining.

Model-free Adaptive Dynamic Programming Based Near-optimal Decentralized Tracking Control of Reconfigurable Manipulators

Bo Zhao,Yuanchun Li 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.2

In this paper, a model-free near-optimal decentralized tracking control (DTC) scheme is developed for reconfigurable manipulators via adaptive dynamic programming algorithm. The proposed controller can be divided into two parts, namely local desired controller and local tracking error controller. In order to remove the normboundedness assumption of interconnections, desired states of coupled subsystems are employed to substitute their actual states. Using the local input/output data, the unknown subsystem dynamics of reconfigurable manipulators can be identified by constructing local neural network (NN) identifiers. With the help of the identified dynamics, the local desired control can be derived directly with corresponding desired states. Then, for tracking error subsystems, the local tracking error control is investigated by the approximate improved local cost function via local critic NN and the identified input gain matrix. To overcome the overall error caused by the substitution, identification and critic NN approximation, a robust compensation is added to construct the improved local cost function that reflects the overall error, regulation and control simultaneously. Therefore, the closed-loop tracking system can be guaranteed to be asymptotically stable via Lyapunov stability theorem. Two 2-degree of freedom reconfigurable manipulators with different configurations are employed to demonstrate the effectiveness of the proposed modelfree near-optimal DTC scheme.

The clustering of the SDSS-IV extended Baryon Oscillation Spectroscopic Survey DR14 quasar sample: a tomographic measurement of cosmic structure growth and expansion rate based on optimal redshift weights

Zhao, Gong-Bo,Wang, Yuting,Saito, Shun,Gil-Marí,n, Hé,ctor,Percival, Will J,Wang, Dandan,Chuang, Chia-Hsun,Ruggeri, Rossana,Mueller, Eva-Maria,Zhu, Fangzhou,Ross, Ashley J,Tojeiro, Rita,P& Oxford University Press 2019 Monthly notices of the Royal Astronomical Society Vol.482 No.3

The design and fabrication of 81.25 MHz RFQ for Low Energy Accelerator Facility

Bo Zhao,Shuping Chen,Tieming Zhu,Fengfeng Wang,Xiaofeng Jin,Chenxing Li,Wei Ma,Bin Zhang 한국원자력학회 2019 Nuclear Engineering and Technology Vol.51 No.2

To provide high shunt impendence with low power losses, an 81.25 MHz continuous wave (CW) radiofrequency quadrupole (RFQ) accelerator has been designed and machined as parts of the Low EnergyAccelerator Facility (LEAF). In this paper, the mechanical structure and the main processing technology ofthe RFQ cavities are described according to the physical and geometric parameters requirements of theRFQ. The fabrication of the RFQ has been completed and the test results agree well with the designrequirements. The RFQ accelerator will work in Institute of Modern Physics, Chinese Academy of Sciencesin 2018.

Thermal Conductive Epoxy Enhanced by Nanodiamond-Coated Carbon Nanotubes

Bo Zhao,Guohua Jiang 대한금속·재료학회 2017 ELECTRONIC MATERIALS LETTERS Vol.13 No.6

Nanodiamond (ND) particles were coated on the surface of carbonnanotubes (CNTs) by chemical reactions. Reliable bonding wasformed by the combination of acyl chloride on NDs and amine groupon CNTs. ND coated CNTs (CNT-ND) were dispersed into epoxy tofabricate thermal conductive resins. The results show that the surfaceenergy of CNTs is decreased by the coated NDs, which is contributedto the excellent dispersion of CNT-NDs in the epoxy matrix. Theheat-transfer channels were built by the venous CNTs cooperatingwith the coated NDs, which not only plays an effective role of heatconduction for CNTs and NDs, but also avoids the electrical leakageby the protection of NDs surrounding outside of CNTs. Electrical andthermal conductance measurements demonstrate that the influence ofthe CNT-ND incorporation on the electrical conductance is minor,however, the thermal conductivity is improved significantly for theepoxy filled with CNT-ND.

Mass transfer and kinetics study on the sulfite forced oxidation with manganese ion catalyst

Zhao Bo,Li Yan,Zhuo Yuqun,Tong Huiling,Zhang Xiaowen,Chen Changhe 한국화학공학회 2007 Korean Journal of Chemical Engineering Vol.24 No.3

limestone scrubbing is the most common flue gas desulfurization process (FGD) for control of sulfurdioxide emissions from the combustion of fossil fuels. Forced oxidation, which controls the overall reaction of the sulfurdioxide absorption, is the key path of the process. Manganese which comes from the coal is one of the catalysts duringthe forced oxidation process. In the present work, the two-film theory was used to analyze the sulfite forced oxidationreaction with an image boundary recognition technique, and the oxidation rate was experimentally studied by contactingpure oxygen with a sodium sulfite solution. There was a critical sulfite concentration 0.328 mol/Lwithout catalyst ortion constant k; furthermore, we obtained the order with respect to the sulfite and Mn2+ concentrations. When the Mn2+catalyst concentration was kept unchanged, the sulfite oxidation reaction rate was controlled by dual film and the reac-tion kinetics was first order with respect to sulfite while concentration was below 0.328 mol/L; the sulfite oxidationreaction rate was controlled by gas film only and the reaction kinetics was zero order with respect to sulfite while concentration over 0.328 mol/L. When concentration was kept unchanged, the sulfite oxidation reaction rate de-pended on gas-liquid mass transfer and the reaction kinetics was diferent in various stages with respect to Mn2+ con-centrations.

Multiple Faults Detection and Isolation via Decentralized Sliding Mode Observer for Reconfigurable Manipulator

Bo Zhao,Chenghao Li,Tianhao Ma,Yuanchun Li 대한전기학회 2015 Journal of Electrical Engineering & Technology Vol.10 No.6

This paper considers a decentralized multiple faults detection and isolation (FDI) scheme for reconfigurable manipulators. Inspired by their modularization property, a global sliding mode (GSM) based stable adaptive fuzzy decentralized controller is investigated for the system in fault free, while for the system suffering from multiple faults (actuator fault and sensor fault), the decentralized sliding mode observer (DSMO) is employed to detect their occurrence. Hereafter, the time and location of faults can be determined by a fault isolation scheme via a bank of DSMOs. Finally, the effectiveness of the proposed schemes in controlling, detecting and isolating faults is illustrated by the simulations of two 3-DOF reconfigurable manipulators with different configurations successfully.

Polyvinylchloride Ultrafiltration Membranes Modified with Different SiO2 Particles and Their Antifouling Mechanism for Oil Extraction Wastewater

Zhao, Fang-Bo,Yu, Zhen-Jiang,Park, Hee-Deung,Liu, Xu-Yang,Song, Xiang-Ru,Li, Zhan-Shuang American Society of Civil Engineers 2015 Journal of environmental engineering Vol.141 No.8

Cloning and Expression Analysis of Gonadogenesis-associated Gene SPATA4 from Rainbow Trout (Oncorhynchus mykiss)

( Bo Wen Liu ),( Shang Feng Liu ),( Shan He ),( Ying Zhao ),( Hong Xia Hu ),( Zhao Wang ) 생화학분자생물학회 2005 BMB Reports Vol.38 No.2

Gonadogenesis is a complicated process which involves multi-gene interactions. A rainbow trout (Oncorhynchus mykiss) gene spermatogenesis associated 4 (SPATA4) was cloned and characterized from adult rainbow trout testis. The cDNA sequence of rainbow trout SPATA4 contains an open reading frame of 1, 081 nucleatides encoding a putative protein of 259 amino acids. The putative protein from rainbow trout shares a 76.8% homology with zebrafish SPATA4. No trans-membrane regions or signal peptide were detected using bioinformatics methods. Subcellular localization analysis revealed that rainbow trout SPATA4 was a nuclear protein with highest possibility (39.1%). Multi-tissue reverse transcriptase PCR (RT-PCR) was performed to examine the distribution of rainbow trout SPATA4 in eleven organs of adult rainbow trout. The result demonstrated that this gene express specifically in testis and slight amount of expression was detected in ovary. Further analysis of SPATA4 characterization and function in rainbow trout may provide insight into the understanding of gonadogenesis process.

Localized surface plasmon resonance coupling in Au nanoparticles/phosphorus dendrimer multilayer thin films fabricated by layer-by-layer self-assembly method

Zhao, Wen Bo,Park, Jeongju,Caminade, Anne-Marie,Jeong, Seong-Jun,Jang, Yoon Hee,Kim, Sang Ouk,Majoral, Jean-Pierre,Cho, Jinhan,Kim, Dong Ha Royal Society of Chemistry 2009 Journal of materials chemistry Vol.19 No.14

<P>Multilayer thin films of anionic gold nanoparticles (Au<SUB>NPs</SUB>) and cationic phosphorus dendrimers were deposited on 3-(diethoxymethyl-silyl)propylamine (3-APDMES)-coated substrates using layer-by-layer (LbL) assembly driven by electrostatic interactions. The growth of Au/dendrimer multilayers composed of Au<SUB>NPs</SUB> with diameters of ∼3 nm and ∼16 nm and dendrimer with ∼2 nm diameter was monitored by UV-vis spectroscopy. The relative amounts of Au<SUB>NPs</SUB> and dendrimers in the multilayer films were calculated using a quartz crystal microbalance. The Au-containing multilayers have two surface plasmon bands at ∼530 nm and ∼600 nm, where the latter exhibits a red shift upon increasing the areal density of AuNPs as well as increasing the layer number. The localized surface plasmon resonance (LSPR) band of the hybrid films can be tuned by adding NaCl to the dendrimer solution or by removing the organic matrix. These results demonstrate that the near-field coupling between the LSPR bands of neighboring Au layers is responsible for the controlled absorption behavior. Au mesoporous films after removing dendrimers show LSPR sensing properties for alcohols with different refractive indices in the range 1.33–1.41. A linear relationship was obtained between the LSPR peak wavelength and the refractive index of the surrounding medium.</P> <P>Graphic Abstract</P><P>LSPR coupling behaviour in multilayers of gold nanoparticles (Au<SUB>NPs</SUB>) and phosphorus dendrimers is discussed, where marked blue or red shifts were observed from the LSPR band upon controlled coupling between adjacent Au<SUB>NPs</SUB>. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b814116a'> </P>