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Activity Model and Its Application in Quarternary System CaO-FeO-SiO_2-WO_3

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Journal of Iron and Steel Research International 2010年第1期17卷 12-17页

作者： guo pei-min LI Zheng-bang ZHAO pei State Key Laboratory for Advanced Iron and Steel Processes and Materials Central Iron andSteel Research Institute Beijing 100081 China

The activity model of CaO-FeO-SiO2-WO3 quarternary system is built according to the coexistence theory of slag structure and the reduction thermodynamics of scheelite is discussed by using this model. The activities of SiO2 and WO3 decrease, while the activity of CaO increases with increasing the basicity of slag. Among SiC, carbon and silicon reactants, the reducing capability of SiC is the strongest, while that of carbon is the poorest at high temperature （about 1 873 K）. Increasing the content of silicon or carbon is beneficial for increasing the yield of tungsten. Oxidizability of slag has a significant effect on the yield of tungsten. Controlling basicity and oxidizability of slag can decrease the oxidation loss of tungsten.

关键词： activity model scheelite thermodynamics direct reduction

Reduction of 1-3 mm Iron Ore by CO on Fluidized Bed

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Journal of Iron and Steel Research International 2011年第3期18卷 1-5页

作者： PANG Jian-ming guo pei-min ZHAO pei The State Key Laboratory for Advanced Steel Processes and Products Central Iron and Steel Research InstituteBeijing 100081China

The reduction-degree of the sample increases and the utilization ratio of gas decreases when the reaction lasts longer time,which indicates that the reaction is faster at the beginning of reduction,while it becomes slower in subsequent *** higher the reaction temperature,the higher the utilization ratio of gas and the reduction-degree are,but the difference of utilization ratio among the different temperatures becomes smaller with *** utilization ratio of gas can reach about 8% and the reduction-degree is 80% for 20 min reduction at 850 ℃,indicating that the reduction reaction by CO is very fast at high *** higher the reaction temperature,the higher the apparent reaction rate constant is,but the difference of apparent reaction rate constant among the different temperatures becomes *** apparent activation energy is about 59.11 kJ/mol in the fluidized bed *** increase of reduction-degree with gas velocity shows quite good linearity,indicating that at high temperature even higher velocity of reducing gas can be used to improve the productivity of reactor when CO is used as reducing *** the increase of charge height,the metallization ratio and the reduction-degree decrease,but the utilization ratio of gas increases.

关键词： CO fluidized bed fine powder iron ore reduction-degree

Reduction of 1-3 mm iron ore by H_2 in a fluidized bed

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 620-625页

作者： Jian-ming Pang pei-min guo pei Zhao Chao-zhen Cao Ding-guo Zhao Duo-gang Wang The State Key Laboratory for Advanced Steel Processes and Materials Central Iron and Steel Research Institute Beijing 100081 China

The reduction of 1-3 mm fine powder of iron ore by H2 was conducted in a lab-fabricated kg class high temperature fluidized bed. The results show that the differential pressure in the fluidized bed, which has small fluctuation with time, increases with the increase of gas flowing velocity. The utilization ratio of gas decreases when the reaction lasts longer time indicating that the reaction is faster at the beginning of reduction and becomes slower in the latter process. The higher the reaction temperature is, the higher the utilization ratio of gas is, but the difference of utilization ratio among the different temperatures becomes smaller with time. The utilization ratio of gas and the metallization ratio can reach 9% and 84% respectively at 750℃ for 20 min, which shows the reduction reaction by H2 is very fast. The increase of metallization ratio with gas velocity performs quite good linearity, which shows that a higher velocity of reducing gas can be used to improve the productivity of the reactor when H2 is used as reducing gas. With the increase of charge height, the metallization ratio decreases, but the utilization ratio of gas increases. The reaction temperature can be reduced to 700-750℃ from 800-850℃ when H2 is used as reducing gas.

关键词： hydrogen fluidized bed fine powder iron ore ironmaking reduction reaction

The competing mini-dumbbell mechanism:new insights into CCTG repeat expansion

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Signal Transduction and Targeted Therapy 2016年第1期1卷 21-26页

作者： pei guo Sik Lok Lam Department of Chemistry The Chinese University of Hong KongShatinHong Kong

CCTG repeat expansions in intron 1 of the cellular nucleic acid-binding protein gene are associated with myotonic dystrophy type ***,we have reported a novel mini-dumbbell(MDB)structure formed by two CCTG or TTTA repeats,which potentially has a critical role in repeat *** we present a mechanism,called the competing MDB mechanism,to explain how the formation of MDB can lead to efficient mismatch repair(MMR)escape and thus CCTG repeat expansions during DNA *** a long tract of CCTG repeats,two competing MDBs can be formed in any segment of three *** exchange between these MDBs will make the commonly occupied repeat behave like a *** participations of the 5′-or 3′-flanking repeat in forming competing MDBs will make the mini-loop shift in the 5′-or 3′-direction,thereby providing a pathway for the mini-loop to escape from *** avoid the complications due to the formation of hairpin conformers in longer CCTG repeats,we made use of TTTA repeats as model sequences to demonstrate the formation of competing MDBs and shifting of mini-loop in a long tract of repeating sequence.

关键词： mechanism competing expansion

Multi-Field Analysis and Experimental Verification on Piezoelectric Valve-Less Pumps Actuated by Centrifugal Force

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 1032-1043页

作者： Yu-Ting Ma Zhi-guo pei Zhong-Xiang Chen CAS Key Lab of Bio-Medical Diagnostics Suzhou Institute of Biomedical Engineering and TechnologyChinese Academy of SciencesSuzhou 215163China

A piezoelectric centrifugal pump was developed previously to overcome the low frequency responses of piezoelectric pumps with check valves and liquid reflux of conventional valveless piezoelectric pumps. However, the electro-mechanical-fluidic analysis on this pump has not been done. Therefore, multi-field analysis and experimen- tal verification on piezoelectrically actuated centrifugal valveless pumps are conducted for liquid transport appli- cations. The valveless pump consists of two piezoelectric sheets and a metal tube with piezoelectric elements pushing the metal tube to swing at the first bending resonant fre- quency. The centrifugal force generated by the swinging motion will force the liquid out of the metal tube. The governing equations for the solid and fluid domains are established, and the coupling relations of the mechanical, electrical and fluid fields are described. The bending res- onant frequency and bending mode in solid domain are discussed, and the liquid flow rate, velocity profile, and gauge pressure are investigated in fluid domain. The working frequency and flow rate concerning different components sizes are analyzed and verified through experiments to guide the pump design. A fabricated pro- totype with an outer diameter of 2.2 mm and a length of 80 mm produced the largest flow rate of 13.8 mL/min at backpressure of 0.8 kPa with driving voltage of 80 Vpp. Bysolving the electro-mechanical-fluidic coupling problem, the model developed can provide theoretical guidance on the optimization of centrifugal valveless pump characters.

关键词： Valveless pump Centrifugal force Piezoelectric pump Multi-field analysis

Comparative analysis of protein kinases and associated domains between Ascomycota and Basidiomycota

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Journal of Integrative Agriculture 2019年第1期18卷 96-107页

作者： pei guo-liang guo Jun WANG Qin-hu KANG Zhen-sheng State Key Laboratory of Crop Stress Biology for Arid Areas College of Plant ProtectionNorthwest A&F University

Protein kinases play an important role in every aspect of cellular *** this study,we systemically identified protein kinases from the predicted proteomes of 59 representative fungi from Ascomycota and *** analysis revealed that fungi from Ascomycota and Basidiomycota differed in the number and variety of protein *** groups of protein kinases,such as calmodulin/calcium regulated kinases(CMGC) and those with the highest group percentages are the most prevalent protein kinases among all fungal species *** contrast,the STE group(homologs of the yeast STE7,STE11 and STE20 genes),was more abundant in Basidiomycetes than in ***,the distribution of some protein kinase families appeared to be *** tyrosine kinase-like(TKL) group had a higher protein kinase density in Agaricomycotina *** addition,the distribution of accessory domains,which could have functional implications,demonstrated that usage bias varied between the two *** component analysis revealed a divergence between the main functional domains and associated domains in *** study provides novel insights into the variety and expansion of fungal protein kinases between Ascomycota and Basidiomycota.

关键词： protein kinases associated domains Ascomycota Basidiomycota

Non-Frontal Facial Expression Recognition Using a Depth-Patch Based Deep Neural Network

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Journal of Computer Science & Technology 2017年第6期32卷 1172-1185页

作者： Nai-Ming Yao Hui Chen Qing-pei guo Hong-An Wang Beijing Key Laboratory of Human-Computer Interaction Institute of Software Chinese Academy of Sciences Bcijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Computer Science Institute of Software Chinese Academy of Sciences Beijing 100190 China

The challenge of coping with non-frontal head poses during facial expression recognition results in considerable reduction of accuracy and robustness when capturing expressions that occur during natural communications. In this paper, we attempt to recognize facial expressions under poses with large rotation angles from 2D videos. A depth^patch based 4D expression representation model is proposed. It was reconstructed from 2D dynamic images for delineating continuous spatial changes and temporal context under non-frontal cases. Furthermore, we present an effective deep neural network classifier, which can accurately capture pose-variant expression features from the depth patches and recognize non-frontal expressions. Experimental results on the BU-4DFE database show that the proposed method achieves a high recognition accuracy of 86.87% for non-frontal facial expressions within a range of head rotation angle of up to 52%, outperforming existing methods. We also present a quantitative analysis of the components contributing to the performance gain through tests on the BU-4DFE and Multi-PIE datasets.

关键词： facial expression recognition non-frontal head pose depth spatial-temporal convolutional neural network

Antitumor and antimicrobial activities of endophytic fungi from medicinal parts of Aquilaria sinensis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第5期12卷 385-392页

作者： Jin-long CUI Shun-xing guo pei-gen XIAO Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100193 China

The purpose of this study was to isolate and characterize endophytic fungi from the stem tissue which can produce fragrant ingredients in Aquilaria sinensis(also called agarwood) to determine their antitumor and antimicrobial ***-eight fungal endophytes were isolated from agarwood by strict sterile sample preparation and were classified into 14 genera and 4 taxonomic classes(Sordariomycetes,Dothideomycetes,Saccharomycetes,and Zy-gomycetes) based on molecular *** the 28 isolates,13(46.4%) showed antimicrobial activity against at least one of the test strains by the agar well diffusion method,and 23 isolates(82.1%) displayed antitumor activity against at least one of five cancer cell lines by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) *** diameters of inhibition zones of YNAS07,YNAS14,HNAS04,HNAS05,HNAS08,and HNAS11 were equal to or higher than 14.0 mm against Staphylococcus aureus,Escherichia coli,Bacillus subtilis,***,Aspergillus fumigatus,and ***,*** inhibition rates of YNAS06,YNAS08,and HNAS06 were not less than 60% to 293-T,293-T,and SKVO3 cells,*** results suggest that the endophytic fungi associated with agarwood will provide us with not only useful micro-ecological information,but also potential antimicrobial and anti-tumor agents.

关键词： Agar diffusion method Agarwood Antimicrobial bioactivity Antitumor bioactivity Endophytic fungi

Metal Functional Materials and Their Industrialization on Turn of the Century

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Journal of Iron and Steel Research International 2000年第2期7卷 37-44页

作者： guo pei-min ZHANG Jia-wen LI Zheng-bang Central Iron & Steel Research Institute

A brief introduction of the connotation and characteristics of metal functional materials was presented. The current research and development of several important materials and the difference between home and world advanced level were described. The latest trend of research and development was discussed. The industrialization and market for several new metal functional materials were commented and some opinions also were given.

关键词： metal functional materials research and development market