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Effect of Lithium Nitrate on the Structure and Property of α-Al2O3 Platelets Prepared via Solid-state Reaction

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China Petroleum Processing & Petrochemical Technology 2017年第2期19卷 8-13页

作者： miao Zhuang Shi Jiangong miao Qingyuan Hao Jianwei zhang Yi zhang Wenping SINOPEC Catalyst Beijing Co. Ltd. Beijing 102500 National Laboratory of Flame Retardant Materials National Engineering and Technology Research Center of Flame Retardant Materials Beijing Institute of Technology Beijing 100081 Production and Technology Department Sinopec Catalyst Co. Ltd. Beijing 100029

The α-Al_2O_3 platelets were prepared via solid-state reactions and the effect of the amount of lithium nitrate additive on the property of the platelets was investigated. The ICP results indicated that the high temperature calcination process resulted in a large loss of lithium species because of volatilization, but there was still a small amount of residual lithium species in the α-Al_2O_3 platelets. The SEM micrographs showed that lithium nitrate led to decrease in the thickness of α-Al_2O_3 platelets and irregular morphology of aggregates. Pore structures results exhibited that addition of lithium nitrate led to decrease in the pore size and increase in the specific surface area of aggregates of α-Al_2O_3 platelets. The XRD and IR patterns suggested that the residual lithium and aluminum oxide formed LiAl_5O_8. The existence of LiAl_5O_8 was the basic reason for the changed performance of α-Al_2O_3 platelets.

关键词： solid-state reaction α-Al2O3 platelets LiNO3 property

An Improved Time Domain Approach for Analysis of Floating Bridges Based on Dynamic Finite Element Method and State-Space Model

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China Ocean Engineering 2022年第5期36卷 682-696页

作者： XIANG Sheng CHENG Bin zhang Feng-yu TANG miao State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory for Digital Maintenance of Buildings and Infrastructure Shanghai Jiao Tong UniversityShanghai 200240China Department of Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Civil Engineering Fuzhou UniversityFuzhou 350108China

The floating bridge bears the dead weight and live load with buoyancy,and has wide application prospect in deep-water transportation *** structural analysis of floating bridge is challenging due to the complicated fluid-solid coupling effects of wind and *** this research,a novel time domain approach combining dynamic finite element method and state-space model(SSM)is established for the refined analysis of floating *** dynamic coupled effects induced by wave excitation load,radiation load and buffeting load are carefully ***-precision fitted SSMs for pontoons are established to enhance the calculation efficiency of hydrodynamic radiation forces in time *** dispersion relation is also introduced in the analysis model to appropriately consider the phase differences of wave loads on *** proposed approach is then employed to simulate the dynamic responses of a scaled floating bridge model which has been tested under real wind and wave loads in *** numerical results are found to agree well with the test data regarding the structural responses of floating bridge under the considered environmental *** proposed time domain approach is considered to be accurate and effective in simulating the structural behaviors of floating bridge under typical environmental conditions.

关键词： floating bridge time domain analysis dynamic analysis state-space model environmental load

Cobalt(Ⅲ)hydride HAT mediated enantioselective intramolecular hydroamination access to chiral pyrrolidines

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Science China Chemistry 2024年第6期67卷 2002-2008页

作者： Qi Meng Tao Qin Huanran miao Ge zhang Qian zhang Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun130024China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Enantioenriched pyrrolidines and derivatives are ubiquitous substructures in compounds of importance to medicinal and biological ***,we report an efficient cobalt-catalyzed intramolecular asymmetric hydroamination reaction that produces chiral pyrrolidines with good to excellent yield and *** with previously reported radicalinvolved methodologies for enantioenriched pyrrolidines,these conditions feature two elegant versatilities,enabling(1)the use of cobalt-catalyzed hydrogen atom transfer(HAT)to generate organocobalt intermediates that bring radical reaction to organometallic chemistry,and(2)enantioselective intramolecular C-N bond forging through an S_(N)2-like displacement involving dynamic kinetic resolution(DKR).This approach provides a new alternative and efficient methodology for enantioselective radical-involved C-N bond construction that can be used in the synthesis of both chiral pyrrolidines and homologous nitrogen heterocycles.

关键词： asymmetric catalysis radical hydroamination cobalt catalysis hydrogen atom transfer

A Review on Deep Learning in Medical Image Reconstruction

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Journal of the Operations Research Society of China 2020年第2期8卷 311-340页

作者： Hai-miao zhang Bin Dong Beijing International Center for Mathematical Research Peking UniversityBeijing 100871China

Medical imaging is crucial in modern clinics to provide guidance to the diagnosis and treatment of *** image reconstruction is one of the most fundamental and important components of medical imaging,whose major objective is to acquire high-quality medical images for clinical usage at the minimal cost and risk to the *** models in medical image reconstruction or,more generally,image restoration in computer vision have been playing a prominent *** mathematical models are mostly designed by human knowledge or hypothesis on the image to be reconstructed,and we shall call these models handcrafted ***,handcrafted plus data-driven modeling started to emerge which still mostly relies on human designs,while part of the model is learned from the observed *** recently,as more data and computation resources are made available,deep learning based models(or deep models)pushed the data-driven modeling to the extreme where the models are mostly based on learning with minimal human *** handcrafted and data-driven modeling have their own advantages and *** handcrafted models are well interpretable with solid theoretical supports on the robustness,recoverability,complexity,etc.,whereas they may not be flexible and sophisticated enough to fully leverage large data ***-driven models,especially deep models,on the other hand,are generally much more flexible and effective in extracting useful information from large data sets,while they are currently still in lack of theoretical ***,one of the major research trends in medical imaging is to combine handcrafted modeling with deep modeling so that we can enjoy benefits from both *** major part of this article is to provide a conceptual review of some recent works on deep modeling from the unrolling dynamics *** viewpoint stimulates new designs of neural network architectures with inspirations from optimization algorit

关键词： Medical imaging Deep learning Unrolling dynamics Handcrafted modeling Deep modeling Image reconstruction

Effects of Dietary Carbohydrate-to-Lipid Ratio on the Growth Performance and Feed Utilization of Juvenile Turbot(Scophthalmus maximus)

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Journal of Ocean University of China 2016年第4期15卷 660-666页

作者： miao Shuyan NIE Qin miao Huijun zhang Wenbing MAI Kangsen The Key Laboratory of Aquaculture Nutrition and Feed of Ministry of Agriculture The Key Laboratoryof Mariculture of Ministry of Education Ocean University of China Qingdao 266003 P. R. China College of Animal Science and Technology Yangzhou University Yangzhou 225009 P. R. China

A 9-week feeding trial was conducted to investigate the effects of dietary carbohydrate to lipid ratio(CHO:LIP) on the growth performance and feed utilization of juvenile turbot Scophthalmus maximus(initial body weight 8.75 g ± 0.04 g). Four isonitrogenous and isoenergetic low protein level(39%) diets were formulated with increasing ratios of dietary carbohydrate to lipid(2:18, 6:18, 18:12 and 28:6). A high protein level(50%) diet with the 2:12 ratio of carbohydrate to lipid was used as the control. Results showed that the survival rate, contents of moisture, crude protein and ash in muscle were not significantly affected by dietary treatments. With the dietary CHO:LIP ratio increased from 2:18 to 18:12, weight gain rate significantly increased(P < 0.05). Higher dietary CHO:LIP ratio(28:6) resulted in the significantly decreased weight gain rate(P < 0.05). Meanwhile, this treatment also resulted in the highest daily feed intake and liver glycogen content, as well as the lowest feed efficiency(P < 0.05). Muscle glycogen content in fish fed the diet with 2:12 or 2:18 CHO:LIP ratio was significantly lower than those fed with the other three diets(P < 0.05). The present results confirmed that the juvenile turbot can utilize carbohydrate. Furthermore, the appropriate ratio of dietary carbohydrate to lipid was important to the growth and feed utilization of turbot. The proper CHO:LIP ratio based on the growth performance in the present study was determined to be 18:12 when the dietary protein level was 39%.

关键词： Scophthalmus juvenile Lipid carbohydrate dietary glycogen dextrin lipid Paralichthys intake

Present Situation of the Anti-Fatigue Processing of High-Strength Steel Internal Thread Based on Cold Extrusion Technology:A Review

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Chinese Journal of Mechanical Engineering 2017年第2期30卷 231-240页

作者： Hong miao Cheng JIANG Sixing LIU Shanwen zhang Yanjun zhang College of Mechanical Engineering Yangzhou UniversityYangzhou 225009China Key Laboratory of Modem Agricultural Equipment Nanjing Research Institute for Agricultural Mechanization Ministry of AgricultureNanjing 210014China

The adoption of cold-extrusion forming for internal thread net forming becomes an important component of anti-fatigue processing with the development of internal thread processing towards high performance, low cost and low energy consumption. It has vast application foreground in the field of aviation, spaceflight, high speed train and etc. The internal thread processing and anti-fatigue manufacture technology are summarized. In terms of the perspective of processing quality and fatigue serving life, the advantages and disadvantages of the processing methods from are compared. The internal thread cold-extrusion processing technology is investigated for the purpose of improving the anti-fatigue serving life of internal thread. The superiorities of the plastic deformation law and surface integrity of the metal layer in the course of cold extrusion for improving its stability and economy are summed up. The proposed research forecasts the develop- ment tendency of the internal thread anti-fatigue manufacturing technology.

关键词： High-strength steel · Internal thread · Coldextrusion · Anti-fatigue · Surface integrity

Physical modelling of particle transport phenomenon and vibration behavior of converter with bottom powder injection

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Journal of Iron and Steel Research International 2022年第11期29卷 1771-1788页

作者： Jing-shi zhang Wen-tao Lou miao-yong Zhu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

A cold model of top-bottom blown converter was set up to study the particle transport phenomenon and vibration performance of converter with bottom powder *** effect of bottom blowing flow rates,tuyere diameters,arrangements,and powder to gas mass ratios on powder distribution and furnace body vibration was *** results show that the bottom injection parameters and modes have significant effects on the particle transport behavior and furnace *** powder dispersion uniformity and furnace vibration increase with the increase in bottom blowing tuyere *** the lower range of bottom blowing flow rates and powder to gas mass ratios,the powder dispersion uniformity is improved with the increase in ***,in the higher range,the excessive furnace vibration leads to reduction in uniformity in powder *** the bottom blowing tuyeres arrange at double arrangement of 0.5R(R refers to the radius of the bottom)distance between tuyere and center of bath bottom,the converter has optimal particle transport behavior and vibration *** vibration law of converter with bottom powder injection was revealed by deducing the empirical formulas of furnace vibration maximum *** vibration intensity is affected by Froude number,powder to gas mass ratio,and tuyere arrangement.

关键词： Converter steelmaking Bottom powder injection Powder dispersion uniformity Furnace vibration Physical modelling

Photomultiplication type all-polymer photodetectors with single carrier transport property

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Science China Chemistry 2019年第12期62卷 1619-1624页

作者： Jianli miao Mingde Du Ying Fang Xiaoli zhang Fujun zhang Key Laboratory of Luminescence and Optical Information Ministry of EducationBeijing Jiaotong UniversityBeijing 100044China National Center for Nanoscience and Technology Beijing 100190China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

Photomultiplication(PM)type all-polymer photodetectors(all-PPDs)are first demonstrated with the sandwich structure of ITO/PEDOT:PSS/PBDB-T:PZ1(100:x,wt/wt)/*** optimal PM type all-PPDs with PBDB-T:PZ1(100:3,wt/wt)as active layers exhibit external quantum efficiency(EQE)of>100%in the spectral range from 310 to 790 *** 675 nm light illumination,the champion EQE value arrives to 1,470%at-20 V bias and the specific detectivity approaches 1×10^12 Jones at-10 V *** PM phenomenon in all-PPDs results from hole tunneling injection assisted by interfacial band bending induced by trapped electrons in PZ1 near Al *** EQE values of optimal PM type all-PPDs still remained over 90%of the original value after 60 d of the storage in a high-purity nitrogen-filled glove box.

关键词： photomultiplication all-polymer photodetectors tunneling injection stability

Bi-variable damage model for fatigue life prediction of metal components

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Acta Mechanica Sinica 2011年第3期27卷 416-425页

作者： miao zhang Qing-Chun Meng Xing zhang Wei-Ping Hu Division 508 School of Aeronautic Science and Engineering Beihang University 100191 Beijing China

Based on the theory of continuum damage mechanics,a bi-variable damage mechanics model is developed,which,according to thermodynamics,is accessible to derivation of damage driving force,damage evolution equation and damage evolution criteria. Furthermore,damage evolution equations of time rate are established by the generalized Drucker＇s postulate. The damage evolution equation of cycle rate is obtained by integrating the time damage evolution equations,and the fatigue life prediction method for smooth specimens under repeated loading with constant strain amplitude is constructed. Likewise,for notched specimens under the repeated loading with constant strain amplitude,the fatigue life prediction method is obtained on the ground of the theory of conservative integral in damage mechanics. Thus,the material parameters in the damage evolution equation can be obtained by reference to the fatigue test results of standard specimens with stress concentration factor equal to 1,2 and 3.

关键词： Bi-variable damage model - Damage evolution equation . Life prediction - Fatigue . Damage mechanics