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Study on the early warning mechanism for the security of blast furnace hearths

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International Journal of Minerals,Metallurgy and Materials 2013年第4期20卷 345-353页

作者： Hong-bo Zhao Shou-feng Huo shu-sen cheng State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing North Billion Technology Co. LTD.

The campaign life of blast furnace （BF） hearths has become the limiting factor for safety and high efficiency production of modern BFs. However, the early warning mechanism of hearth security has not been clear. In this article, based on heat transfer calculations, heat flux and erosion monitoring, the features of heat flux and erosion were analyzed and compared among different types of hearths. The primary detecting elements, mathematical models, evaluating standards, and warning methods were discussed. A novel early warning mechanism with the three-level quantificational standards was proposed for BF hearth security.

关键词： blast furnaces hearths erosion heat flux warning

Experimental Investigation of Nozzle Effects on Thrust and Inlet Pressure of an Air-breathing Pulse Detonation Engine

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Chinese Journal of Aeronautics 2012年第3期25卷 381-387页

作者： CHEN Wenjuan FAN Wei ZHANG qun PENG Changxin YUAN cheng YAN Chuanjun School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China

Nozzle effects on thrust and inlet pressure of a multi-cycle air-breathing pulse detonation engine （APDE） are investigated experimentally. An APDE with 68 mm in diameter and 2 050 mm in length is operated using gasoline/air mixture. Straight nozzle, converging nozzle, converging-diverging nozzle and diverging nozzle are tested. The results show that thrust augmentation of converging-diverging nozzle, diverging nozzle or straight nozzle is better than that of converging nozzle on the whole. Thrust augmentation of straight nozzle is worse than those of converging-diverging nozzle and diverging nozzle. Thrust augmentations of diverging nozzle with larger expansion ratio and converging-diverging nozzle with larger throat area range from 20% to 40% on tested frequencies and are better than those of congeneric other nozzles respectively. Nozzle effects on inlet pressure are also researched. At each frequency it is indicated that filling pressures and average peak pressures of inlet with diverging nozzle and converging-diverging nozzle with large throat cross section area are higher than those with straight nozzle and converging nozzle Pressures near thrust wall increase in an increase order from without nozzle, with diverging nozzle, straight nozzle and converging-diverging nozzle to converging nozzle.

关键词： nozzle effect thrust inlet pressure air-breathing pulse detonation engine

Analysis of Influencing Factors on Lift Coefficients of Autonomous Sailboat Double Sail Propulsion System Based on Vortex Panel Method

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China Ocean Engineering 2019年第6期33卷 746-752页

作者： SUN Zhao-yang YU Jian-cheng ZHANG Ai-qun JIN Qian-long State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China University of Chinese Academy of Sciences Beijing 100049China

Sail is the core part of autonomous sailboat and wing sail is a new type of sail. Wing sail generates not only propulsion but also lateral force and heeling moment. The latter two will affect the navigation status and bring resistance. Double sail can effectively reduce the center of wind pressure and heeling moment. In order to study the effect of distance between two sails, airfoil and attack angle on the total lift coefficient of double sail propulsion system, pressure coefficient distribution and lift coefficient calculation model have been established based on vortex panel method. By using the basic finite solution, the fluid dynamic forces on the two-dimensional sails are *** results show that, the distance in the range of 0 to 1 time chord length, when using the same airfoil in the fore and aft sail, the total lift coefficient of the double sail increases with the increase of distance, finally reaches a stable value in the range of one to three times chord length. Lift coefficients of thicker airfoils are more sensitive to the change of distance. The thicker the airfoil, the longer distance is required of the total lift coefficient toward *** different airfoils are adopted in fore and aft sail, the total lift coefficient increases with the increase of the thickness of aft sail. The smaller the thickness difference is, the more sensitive to the distance change the lift coefficient is. The thinner the fore sail is, the lower the influence will be on the lift coefficient of aft sail.

关键词： autonomous sailboat wing sail double sail vortex panel method lift coefficient

Laser-Generated Transient Lamb Wave in Thin Plates

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Chinese Physics Letters 1996年第1期13卷 24-27页

作者： WU Lei cheng Jian-chun ZHANG shu-yi Institute of Acoustics and Laboratory of Modern Acoustics Nanjing UniversityNanjing 210093

The laser-generated transient Lamb wave in thin isotropic plates is studied theoretically by employing the method of eigenfunction *** thermoelastic displacement field is expressed by symmetric and antisymmetnc Lamb wave modes,so that it is convenient to investigate thg transient excitation of the lowest and higher order Lamb wave *** characteristics of transient Lamb waves in thin materials with different thicknesses are discussed in details.

关键词： expansion transient wave

Machining distortion prediction of aerospace monolithic components

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 661-668页

作者： Yun-bo BI qun-lin cheng Hui-yue DONG Ying-lin KE State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China Shanghai Spaceflight Precision Machinery Research Institute Shanghai 201600 China

To predict the distortion of aerospace monolithic components, a model is established to simulate the numerical control (NC) milling process using 3D finite element method (FEM). In this model, the cutting layer is simplified firstly. Then, the models of cutting force and cutting temperature are established to gain the cutting loads, which are applied to the mesh model of the part. Finally, a prototype of machining simulation environment is developed to simulate the milling process of a spar. Key factors influencing the distortion, such as initial residual stress, cutting loads, fixture layout, cutting sequence, and tool path are considered all together. The total distortion of the spar is predicted and an experiment is conducted to validate the numerical results. It is found that the maximum discrepancy between the simulation results and experiment values is 19.0%

关键词： Monolithic component Machining distortion Finite element simulation

Fecal microbiota transplantation in childhood:past,present,and future

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World Journal of Pediatrics 2023年第9期19卷 813-822页

作者： Xu Gu Zhao‑Hong Chen shu‑cheng Zhang Department of Pediatrics Shengjing Hospital of China Medical University36 Sanhao Street Heping DistrictShenyang 110004China Department of Radiology Shengjing Hospital of China Medical UniversityShenyangChina

Background Fecal microbiota transplantation(FMT)has been well described in the treatment of pediatric diseases;however,the latest updates regarding its use in children are unclear and the concepts involved need to be *** sources We performed advanced searches in the MEDLINE,EMBASE,and Cochrane databases using the keywords“Fecal microbiota transplantation OR Fecal microbiota transfer”in the[Title/Abstract]to identify relevant articles published in English within the last five *** identify additional studies,reference lists of review articles and included studies were manually *** manuscripts(case reports,reviews,and abstracts)were assessed by the *** Among the articles,studies were based on the mechanism(n=28),sample preparation(n=9),delivery approaches(n=23),safety(n=26),and indications(n=67),including Clostridium difficile infection(CDI)and recurrent *** infection(rCDI;n=21),non-alcoholic fatty liver disease(NAFLD;n=10),irritable bowel syndrome(IBS;n=5),inflammatory bowel disease(IBD;n=15),diabetes(n=5),functional constipation(FC;n=4),and autism spectrum disorder(ASD;n=7).Conclusions Concepts of FMT in pediatric diseases have been updated with respect to underlying mechanisms,methodology,indications,and ***-based clinical trials for the use of FMT in pediatric diseases should be introduced to resolve the challenges of dosage,duration,initiation,and the end point of treatment.

关键词： Autism spectrum disorder Children Clostridium difficile infection Fecal microbiota transplantation Functional constipation Safety

Facile and Controllable Assembly of Multiwalled Carbon Nanotubes on Polystyrene Microspheres

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Chinese Journal of Polymer Science 2014年第6期32卷 711-717页

作者：李云兴 Yan Gao cheng Yang Zhao-qun Wang Gi Xue The Key Laboratory of Food Colloids and Biotechnology Ministry of Education School of Chemical and Material Engineering Jiangnan University Department of Polymer Science and Engineering School of Chemistry and Chemical Engineering Nanjing University

Herein a facile and controllable heterocoagulation between polystyrene （PS） microspheres and multiwalled carbon nanotubes （MWCNTs） is introduced based on colloid thermodynamics. The MWCNTs play the role of steric stabilizer for stabilizing the metastable PS microspheres and thus immobilize spontaneously on the surface of PS microspheres. The synthesized MWCNTs-coated PS composite particles have been extensively characterized by scanning electron microscopy, transmission electron microscopy, thermogravimetry and Raman spectroscopy. The results indicate that the structure and morphology of the resultant MWCNTs-coated PS composite particles are significantly affected by the weight ratio of PS and MWNCTs and the amount of poly（vinylpyrrolidone） that is injected into PS dispersion before they are mixed with MWCNTs. Therefore, these composite particles have the potential to produce MWCNTs-based composite materials with controllable mass loading and dispersity of MWCNTs.

关键词： Multiwalled carbon nanotube Polystyrene microsphere Heterocoagulation Structural control Colloidthermodynamics.

National Natural Science Foundation of China leads the comprehensive development of basic research in the field of male reproductive health in China

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Asian Journal of Andrology 2020年第6期22卷 547-548页

作者： shu-Jie Liao Yan-Ying Xu Rui-Juan Sun qun-Yan Lyu Department of Health Science National Natural Science Foundation of ChinaBeijing 100085China Department of Obstetrics and Gynecology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

"Reproductive health"was officially defined as humans and their individual activities related to reproduction throughout their lives,which should be in good health in physical,psychological,and social aspects.1 The basic research on male reproductive health in China can be traced back to the 1960s.2 Since the National Natural Science Foundation of China(NSFC)began systematic support for basic research on male reproductive health in 1988,the field has been systematically developed in *** this regard,we analyze the role of the NSFC on the development of basic research in the field of male reproductive health in China.

关键词： NSFC China. field

Structure and Dynamics of Energy Materials from Machine Learning Simulations:A Topical Review

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Chinese Journal of Chemistry 2021年第11期39卷 3144-3154页

作者： shu-Hui Guan cheng Shang Zhi-Pan Liu Shanghai Academy of Agricultural Sciences Shanghai201403 China Collaborative Innovation Center of Chemistry for Energy Material Shanghai Key Laboratory of molecular Catalysis and Innovative MaterialsKey Laboratory of Computational Physical ScienceDepartment of ChemistryFudan UniversityShanghai200438 China

Energy materials featuring the capability to store and release chemical energy reversibly involve generally complex geometrical structures with multiple *** has been a great challenge to establish the quantitative relationship between the structure of materials and their dynamic physicochemical *** recent years,machine learning(ML)technique has demonstrated its great power in accelerating the research on energy *** topical review introduces the key ingredients and typical applications of ML to energy *** mainly focus on the ML based atomic simulation via ML potentials in different architectures/implementations,including high dimensional neural networks(HDNN),Gaussian approximation potential(GAP),moment tensor potentials(MTP)and stochastic surface walking global optimization with global neural network potential(SSW-NN)*** cases studies,namely,Si,LiC and LiTiO systems,are presented to demonstrate the ability of ML simulation in assessing the thermodynamics and kinetics of complex material *** highlight that the SSW-NN method provides an automated solution for global potential energy surface data collection,ML potential construction and ML simulation,which boosts the current ability for large-scale atomic simulation and thus holds the great promise for fast property evaluation and material discovery.

关键词： Machine learning Materials science Atomic simulation Thermodynamics Kinetics