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Design and Accuracy Analysis of a Metamorphic CNC Flame Cutting Machine for Ship Manufacturing

Chinese Journal of Mechanical Engineering 2016年第5期29卷 930-943页

作者： HU Shenghai zhang Manhui zhang baoping CHEN Xi YU Wei College of Mechanical and Electrical Engineering Harbin Engineering University

The current research of processing large size fabrication holes on complex spatial curved surface mainly focuses on the CNC flame cutting machines design for ship hull of ship manufacturing. However, the existing machines cannot meet the continuous cutting requirements with variable pass conditions through their fixed configuration, and cannot realize high-precision processing as the accuracy theory is not studied adequately. This paper deals with structure design and accuracy prediction technology of novel machine tools for solving the problem of continuous and high-precision cutting. The needed variable trajectory and variable pose kinematic characteristics of non-contact cutting tool are figured out and a metamorphic CNC flame cutting machine designed through metamorphic principle is presented. To analyze kinematic accuracy of the machine, models of joint clearances, manufacturing tolerances and errors in the input variables and error models considering the combined effects are derived based on screw theory after establishing ideal kinematic models. Numerical simulations, processing experiment and trajectory tracking experiment are conducted relative to an eccentric hole with bevels on cylindrical surface respectively. The results of cutting pass contour and kinematic error interval which the position error is from -0.975 mm to ＋0.628 mm and orientation error is from -0.01 rad to ＋0.01 rad indicate that the developed machine can complete cutting process continuously and effectively, and the established kinematic error models are effective although the interval is within a ＇large＇ range. It also shows the matching property between metamorphic principle and variable working tasks, and the mapping correlation between original designing parameters and kinematic errors of machines. This research develops a metamorphic CNC flame cutting machine and establishes kinematic error models for accuracy analysis of machine tools.

关键词： CNC cutting machine metamorphic principle accuracy analysis screw theory error model

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Curing mechanism of alkaline phenolic resin with organic ester

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China Foundry 2014年第5期11卷 447-451页

作者： Huang Renhe Wang Yanmin zhang baoping School of Chemical and Environmental Engineering Shandong University of Science and Technology School of Materials Science and Engineering Shandong University of Science and Technology

To study the curing mechanism of alkaline phenolic resin with organic ester, three esters were chosen to react with three systems - alkaline phenolic resin, potassium hydroxide aqueous solution containing phenol, and potassium hydroxide aqueous solution. The variations of pH, heat release and gel pH during the reactions were monitored and measured. Infrared spectroscopy （IR） and thermal gravity analysis （TG） techniques were used to characterize the curing reaction. It was found that organic ester is only partial y hydrolyzed and resin can be cured through organic ester hydrolysis process as wel as the reaction with redundant organic ester. The sequential curing mechanism of alkaline phenolic resin cured by organic ester was identified as fol ows： a portion of organic ester is firstly hydrolyzed owing to the effect of the strong alkaline; the gel is then formed after the pH decreases to about 10.8-10.88, meanwhile, the redundant organic ester （i.e. non-hydrolysis ester） starts the curing reaction with the resin. It has also been found that the curing rate depends on the hydrolysis velocity of organic ester. The faster the hydrolysis speed of the ester, the faster the curing rate of the resin.

关键词： organic ester alkaline phenolic resin curing process gel curing mechanism

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Multi-fluid Eulerian simulation of binary particles mixing and gas–solids contacting in high solids-flux downer reactor equipped with a lateral particle feeding nozzle

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Chinese Journal of Chemical Engineering 2021年第7期34卷 152-162页

作者： Qiang Zheng Jingxuan Yang Wenhao Lian baoping zhang Xueer Pan Zhonglin zhang Xiaogang Hao Guoqing Guan School of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Chemical Engineering and Technology North University of ChinaTaiyuan 030051China Laboratory of Energy Conversion Engineering Institute of Regional Innovation(IRI)Hirosaki University2-1-3 MatsubaraAomori 030-0813Japan

The performance of binary particles mixing and gas-solids contacting,which is considered qualitatively to have a significant influence on the heat transfer in internal heated circulating fluidized beds,is carefully investigated by means of a numerical approach in the newly developed high solids-flux downer lignite pyrolyzer(φ0.1 m×6.5 m).Since binary particles are used in this system,a reasonably validated 3 D,transient,multi-fluid model,in which three heat transfer modes relating to the convection,conduction and radiation are considered,is adopted to simulate the flow behavior,temperature profiles as well as volatile *** simulation results showed that the solids stream impinges the left wall surface initially and turns towards the right wall in the further downward direction and then shrinks during this process resulting in that the solids concentrate a little more at the central *** the further downward section of the downer,the particle flow disperses near the right wall and develops ***,the coal phase is slowly heated in the downer and it is found that most of the heat absorbed by the coal is from the convection heat transfer *** explore the heat transfer mechanism more quantitatively,two indexes(mixing index and contacting index)are proposed,and it is found that the mixing index initially increased fast and later remained at a relatively flat *** the contact index,it shows a trend with a first rising and then falling,finally rising ***,it is found that the convection heat transfer is closely correlated to the contacting status of gas-coal which indicates that the improving of the gas-coal contacting efficiency should be an effective way to strengthen the coal particle heating process.

关键词： CFD Multiphase flow Downer reactor Numerical simulation Heat transfer

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One-step uniform growth of magnesium hydride nanoparticles on graphene

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Progress in Natural Science:Materials International 2017年第1期27卷 81-87页

作者： Yuqin Huang Guanglin Xia Jie Chen baoping zhang Qian Li Xuebin Yu Department of Materials Science Fudan University State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering Shanghai University Materials Genome Institute Shanghai University

A simple solvent-free method to synthesize MgH;nanoparticles（MgH;NPs） uniformly grown on graphene nanosheets（GNs） has been reported in this paper. Based on the formation of MgH;by di-n-butylmagnesium(（C;H;）;Mg) thermal decomposition under hydrogen pressure, the GNs were added as matrix to hinder the agglomeration and growing of MgH;NPs. The fabricated MgH;/GNs nanocomposites, in which MgH;NPs were homogenously growing in the graphene matrix, have been synthesized by the favorable adsorption energy between（C;H;）;Mg and GNs. Resulting from the one-step solvent-free route, the generated MgH;NPs shows high hydrogen capacity and steady hydriding and dehydriding properties, without the interference of the synthetic medium. At the same time, the size of the fabricated MgH;NPs can be controlled by adjusting the mass ratio of MgH;to graphene, the various hydrogen pressure and temperature. Attributed to smaller size effect, well uniform distribution of high density MgH;NPs, and the agglomeration blocking ability of graphene,the MgH;/GNs-40 wt% exhibits the favorite hydrogen storage performance.

关键词： Hydrogen storage Magnesium hydride Graphene Nanoparticles Nanocomposite

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Heat-induced Internal Strain Relaxation and its Effect on the Microstructure of Polyacrylonitrile-based Carbon Fiber

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Journal of Materials Science & Technology 2014年第10期30卷 1051-1058页

作者： Denghua Li Chunxiang Lu Gangping Wu Yu Yang Zhihai Feng Xiutao Li Feng An baoping zhang National Engineering Laboratory for Carbon Fiber Technology Institute of Coal ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences National Key Laboratory of Advanced Functional Composite Materials Aerospace Research Institute of Materials & Processing Technology

The transformation of the internal strain and its effect on the microstructure of polyacrylonitrile-based carbon fiber during the high-temperature graphitization were investigated. The internal compressive strain within the carbon turbostratic structure was confirmed through a careful analysis by wide-angle X-ray diffraction and Raman spectroscopy. Heat-induced strain/stress relaxation along the fiber axis was observed and was found to have a profound effect on the structure of both the crystallites and microvoids. The results indicated that, the relaxation of residual strain changed the graphite layers from a wrinkled and distorted morphology to a straight and smooth one, and consequently led the crystallites to stack closely and orderly with increasing stack height. The strain relaxation also changed the morphology of crystallites and microvoids, resulting in an anisotropic growth for the latters.

关键词： Graphitizafion Internal strain Microstructures Nanocrystalline Carbon fiber

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Heavy ion and X-ray irradiation alter the cytoskeleton and cytomechanics of cortical neurons

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Neural Regeneration Research 2014年第11期9卷 1129-1137页

作者： Yuting Du Jie zhang Qian Zheng Mingxin Li Yang Liu baoping zhang Bin Liu Hong zhang Guoying Miao School of Stomatology Lanzhou University School of Nuclear Science and Technology Lanzhou University Department of Radiation Biology and Medicine Institute of Modern Physics Chinese Academy of Sciences School of Civil Engineering and Mechanics Lanzhou University Gansu Provincial Hospital

Heavy ion beams with high linear energy transfer exhibit more beneifcial physical and biological performance than conventional X-rays, thus improving the potential of this type of radiotherapy in the treatment of cancer. However, these two radiotherapy modalities both cause inevitable brain injury. The objective of this study was to evaluate the effects of heavy ion and X-ray irra-diation on the cytoskeleton and cytomechanical properties of rat cortical neurons, as well as to determine the potential mechanism of neuronal injury after irradiation. Cortical neurons from 30 new-born mice were irradiated with heavy ion beams at a single dose of 2 Gy and X-rays at a single dose of 4 Gy;subsequent evaluation of their effects were carried out at 24 hours after irradiation. An immunolfuorescence assay showed that after irradiation with both the heavy ion beam and X-rays, the number of primary neurons was signiifcantly decreased, and there was ev-idence of apoptosis. Radiation-induced neuronal injury was more apparent after X-irradiation. Under atomic force microscopy, the neuronal membrane appeared rough and neuronal rigidity had increased. These cell changes were more apparent following exposure to X-rays. Our ifnd-ings indicated that damage caused by heavy ion and X-ray irradiation resulted in the structural distortion and rearrangement of the cytoskeleton, and affected the cytomechanical properties of the cortical neurons. Moreover, this radiation injury to normal neurons was much severer after irradiation with X-rays than after heavy ion beam irradiation.

关键词： nerve regeneration radiation brain injury neurons heavy ion X-ray cytoskeleton cytomechanical properties atomic force microscopy neural regeneration

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Distributed multicast routing algorithm with dynamic performance in multimedia networks

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Engineering Sciences 2009年第3期7卷 28-34页

作者： Zhu baoping zhang Kun School of Computer Science and technology Nanjing University of Science ＆ Technology Nanjing 210094 China

The delay and DVBMT problem is known to be NP-complete. In this paper,an efficient distributed dynamic multicast routing algorithm was proposed to produce routing trees with delay and delay variation constraints. The proposed algorithm is fully distributed,and supports the dynamic reorganizing of the multicast tree in response to changes for the destination. Simulations demonstrate that our algorithm is better in terms of tree delay and routing success ratio as compared with other existing algorithms,and performs excellently in delay variation performance under lower time complexity,which ensures it to support the requirements of real-time multimedia communications more effectively.

关键词： multicast routing distributed algorithm dynamic performance delay and delay variation-bounded multimedia networks

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Spatially discontinuous ionization phenomenon in inhomogeneous soil

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Science China(Technological Sciences) 2010年第4期53卷 918-921页

作者： zhang baoping,HE JinLiang & ZENG Rong State Key Lab of Power Systems,Department of Electrical Engineering,Tsinghua University,Beijing 100084,China State Key Lab of Power Systems Department of Electrical Engineering Tsinghua University Beijing China

By using X-ray film imaging technology,a phenomenon of discontinuous ionization was observed in the inhomogeneous soil around the grounding electrode on which a surge voltage was applied.A simplified two-phase solid-gas model was built to study the electric field distribution in the soil to explain the discontinuous ionization *** showed the differences of the dielectric properties,the shapes and sizes of soil particles can cause discontinuous ionization in the soil.

关键词： discontinuous ionization inhomogeneous soil X-ray film porous medium electric field distribution

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Study of strip-shaped chromatic aberration defects on the surface of an electro-galvanized fingerprint-resistant sheet

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Baosteel Technical Research 2023年第2期17卷 7-14页

作者： HE Yutian HUANG Shengbiao zhang baoping Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai 201999China Cold Rolling Mill Baoshan Iron&Steel Co.Ltd.Shanghai 201900China

Strip-shaped chromatic aberration defects on the surface of an electro-galvanized fingerprint-resistant sheet were systematically studied using Thermo-Calc thermodynamic calculations,scanning electron microscope and X-ray diffractometer analyses,and rapid heat treatment simulation *** formation mechanism of these defects was also *** results show a strong correlation between the defects and the uneven distribution of the Fe(001)component on the surface of the steel *** relatively high proportion of Fe(001)components on the surface of the steel substrate affects the distribution density of the Zn crystal cells in different orientations during the electrodeposition process,which causes the reflection intensity of the light of the galvanized layer to differ from various visual perspectives,and macroscopic strip-shaped chromatic aberration defects are finally *** high proportion of the Fe(001)component on the surface of the steel substrate is mainly related to the following two ***,when the strip steel is hot-rolled,the finishing hot-rolling temperature is close to theγ→αphase transition *** the local temperature on the upper surface of the strip steel is low,γ+αtwo-phase rolling easily occurs,and this results in an uneven stress distribution between theγandαphases after the hot-rolling *** uneven distribution of hot-rolling stress results in the formation of a coarse grain structure in the local area on the surface of the hot-rolled sheet,which strongly affects the subsequent cold rolling and annealing process,and the annealed steel sheet substrate ultimately contains a greater proportion of the Fe(001)*** second,a fast cooling rate(>10 K/s)during the slow cooling stage in the continuous annealing process inhibits the transformation of the Fe(001)to the Fe(111)component on the surface of the cold-rolled steel sheet,and it is then not possible to effectively eliminate the influence of the une

关键词： electro-galvanized fingerprint-resistant sheet strip-shaped chromatic aberration defects texture

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Enhancing the Efficiency of Multi-Electrolyzer Clusters with Lye Mixer:Topology Design and Control Strategy

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Energy Engineering 2024年第10期121卷 3055-3074页

作者： Mingxuan Chen Jun Jia baoping zhang Leiyan Han Mengbo Ji zhangtao Yu Dongfang Li Wenyong Wang Hongjing Jia Huachi Xu China Three Gorges Technology Co. Ltd.Beijing101199China Sichuan Energy Internet Research Institute Tsinghua UniversityChengdu610000China China Three Gorges Renewables(Group)Co. Ltd.Beijing101125China Ordos City Hanxia Renewables Co. Ltd.Ordos014300China

The rise in hydrogen production powered by renewable energy is driving the field toward the adoption of systems comprising multiple alkaline water *** setups present various operational modes:independent operation and multi-electrolyzer parallelization,each with distinct advantages and *** study introduces an innovative configuration that incorporates a mutual lye mixer among electrolyzers,establishing a weakly coupled system that combines the advantages of two *** approach enables efficient heat utilization for faster hot-startup and maintains heat conservation post-lye interconnection,while preserving the option for independent operation after decoupling.A specialized thermal exchange model is developed for this topology,according to the dynamics of the lye *** study further details startup procedures and proposes optimized control strategies tailored to this structural *** heat from the caustic fully heats up the multiple electrolyzers connected to the lye mixing system,enabling a rapid hot start to enhance the system’s ability to track renewable energy.A control strategy is established to reduce heat loss and increase startup speed,and the optimal valve openings of the diverter valve and the manifold valve are *** results indicate a considerable enhancement in operational efficiency,marked by an 18.28%improvement in startup speed and a 6.11%reduction in startup energy consumption inmulti-electrolyzer cluster systems,particularlywhen the systems are synchronized with photovoltaic energy *** findings represent a significant stride toward efficient and sustainable hydrogen production,offering a promising path for large-scale integration of renewable energy.

关键词： Alkaline water electrolyzer hydrogen production control strategy system modeling

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