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Carbon Resources Conversion 2018年第1期1卷 86-93页

作者： Jili Hou yue ma Shuyuan Li Wenzhi Shang a State Key Laboratory of Heavy Oil Processing China University of Petroleum-BeijingBeijing 102249PR China Shenmu Sanjiang Coal Chemical Industry Co. Ltd.Shenmu 719300PR China

The characteristics of sulfur and nitrogen transformation and the emissions’comparison of sulfurous and nitrogenous gas were investigated using SEM,XPS,TG-FTIR and TG-gas analyzer during the combustion process of Shenmu bituminous coal(SM coal)and its *** indicated that porosity and specific surface area of char were enlarged after coal pyrolysis and a large amount of space could be provided for the oxidation reaction of various sulfur species with oxide during the combustion *** sulfur and nitrogen species of the two samples analyzed by XPS showed that,pyritic sulfur,organic sulfide sulfur,sulfone and sulfoxide sulfur in coal were partly transformed to thiophenic sulfur and sulfate sulfur in the pyrolysis of coal,and the total sulfur content in char was ***,the sulfur and nitrogen species’changes in SM coal,char and the ashes determined by XPS showed that sulfur fixation effect was enhanced in the presence of calcium oxide during *** component analysis of the gas during combustion via TG-FTIR indicated that SO2 and NO2 began to escape at 300C and reached maximum at about 1100C,by contrast,the emissions of SO2 and NO2 of char were below that of SM coal throughout the whole combustion *** wide range of TG-gas analyzer analysis revealed that the SO2 and NOx emissions of SM coal were 2.51 and 1.71 times as much as char burning,respectively.

关键词： Coal Char S/N Combustion Transformation XPS TG-FTIR

Effect of Hot Extrusion on Interfacial Microstructure and Tensile Properties of SiC_p/2009Al Composites Fabricated at Different Hot Pressing Temperatures

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Journal of materials Science & Technology 2011年第6期27卷 518-524页

作者： Peng Jin Bolu Xiao Quanzhao Wang Zongyi ma yue Liu Shu Li Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The effects of hot extrusion on the interfacial microstructures and tensile properties of 15 ***/2009Al composites fabricated at different hot pressing temperatures were *** hot extrusion,the relative density of the composites increased,the SiC particle distribution became more uniform,and the SiC particles tended to align along the extrusion ***,the interface bonding was improved after hot extrusion;however,the extrusion exerted no obvious effect on the interfacial reaction products formed during sintering *** tests indicated that the mechanical properties of the composites were improved significantly after *** revealed that the fracture mechanism of the extruded composites fabricated at the hot pressing temperatures below 540℃ was mainly the interfacial *** the extruded composites fabricated at 560-600℃,the fracture was the matrix ductile fracture and the SiC particle *** the composites were hot pressed at or above 620℃,after extrusion,the fracture mechanism of the composites was the matrix ductile fracture,the interface cracking and the SiC particle fracture.

关键词： Aluminum matrix composite Hot extrusion Microstructure Mechanical properties

Improvement Design for Distributed Real-Time Stream Processing Systems

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Journal of Electronic Science and Technology 2019年第1期17卷 3-12页

作者： Wei Jiang Liu-Gen Xu Hai-Bo Hu yue ma the School of Information and Software Engineering University of Electronic Science and Technology of China the Department of Computer Science and Engineering University of Notre Dame

In the era of Big Data, typical architecture of distributed real-time stream processing systems is the combination of Flume, Kafka, and Storm. As a kind of distributed message system, Kafka has the characteristics of horizontal scalability and high throughput, which is manly deployed in many areas in order to address the problem of speed mismatch between message producers and consumers. When using Kafka, we need to quickly receive data sent by producers. In addition, we need to send data to consumers quickly. Therefore, the performance of Kafka is of critical importance to the performance of the whole stream processing system. In this paper, we propose the improved design of real-time stream processing systems, and focus on improving the Kafka's data loading *** use Kafka cat to transfer data from the source to Kafka topic directly, which can reduce the network transmission. We also utilize the memory file system to accelerate the process of data loading, which can address the bottleneck and performance problems caused by disk I/O. Extensive experiments are conducted to evaluate the performance, which show the superiority of our improved design.

关键词： Kafka Kafka cat memory file system message queue real-time stream processing system

Microstructure and Oxidation Behavior of Modified Aluminide Coating on Ni3Al-based Single Crystal Superalloy

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Chinese Journal of Aeronautics 2012年第5期25卷 825-830页

作者： YANG Ruibo WU Yuxiao WU Qiong LI Shusuo ma yue GONG Shengkai School of materials Science and Engineering Beihang UniversityBeijing 100191China

A1, A1-Si and Cr-A1-Si coatings are prepared onto IC20 alloy by powder pack cementation to improve the oxidation resistance of the alloy. The isothermal oxidation behaviors of the coatings and the uncoated IC20 alloy at 1 100 ℃ are comparatively in- vestigated. For the coatings, less weight gains are obtained compared to the uncoated alloy after 100 h thermal exposure. The A1-Si coating exhibits the best oxidation resistance, while the addition of Cr accelerates the scale spallation. Phase transforma- tion from β-NiA1 to y and y＇ occurs in the coating after oxidation for extended periods. The oxidation protection and degradation mechanisms for these coatings are discussed.

关键词： superalloys coatings powder pack cementation microstructure oxidation resistance

An optimized hexagonal quadtree encoding and operation scheme for icosahedral hexagonal discrete global grid systems

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International Journal of Digital Earth 2022年第1期15卷 975-1000页

作者： Long Zhao Guoqing Li Xiaochuang Yao yue ma Qianqian Cao Aerospace Information Research Institute Chinese Academy of SciencesBeijingPeople’s Republic of China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijingPeople’s Republic of China College of Land Science and Technology China Agricultural UniversityBeijingPeople’s Republic of China

Although research on the discrete global grid systems (DGGSs) has become an essential issue in the era of big earth data,there is still a gap between the efficiency of current encoding and operation schemes for hexagonal DGGSs and the needs of practical applications. This paper proposes a novel and efficient encoding and operation scheme of an optimized hexagonal quadtree structure (OHQS) based on aperture 4 hexagonal discrete global grid systems by translation transformation. A vector model is established to describe and calculate the aperture 4 hexagonal grid system. This paper also provides two different grid code addition algorithms based on induction and ijk coordinate transformation. We implement the transformation between OHQS codes and geographic coordinates through the ij,ijk and IJK coordinate systems. Compared with existing schemes,the scheme in this paper greatly improves the efficiency of the addition operation,neighborhood retrieval and coordinate transformation,and the coding is more concise than other aperture 4 hexagonal DGGSs. The encoding operation based on the ijk coordinate system is faster than the encoding operation based on the induction and addition table. Spatial modeling based OHQS DGGSs are also provided. A case study with rainstorms demonstrated the availability of this scheme.

关键词： Discrete global grid systems hexagon quadtree encoding

Deactivation of Cu-SAPO-34 by urea-related deposits at low temperatures and the regeneration

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Journal of Environmental Sciences 2019年第7期31卷 43-51页

作者： yue ma Xiaodong Wu Junyu Zhang Rui Ran Zhichun Si Duan Weng The Key Laboratory of Advanced materials of Ministry of Education School of Materials Science and Engineering Tsinghua University School of Environment Tsinghua University Graduate School at Shenzhen Tsinghua University

Selective catalytic reduction(SCR) with urea catalyzed by Cu-SAPO-34 is an effective method to eliminate NO_x from diesel exhaust. However, urea-related deposits may form during cold-start and urban driving due to low exhaust temperatures. The activity of CuSAPO-34 at 175°C is significantly degraded by urea exposure, and 300°C is required for regeneration. Through in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS) and temperature-programmed hydrolysis studies, the dominant stable deposit at 175°C is identified as biuret, which can be eliminated at 300°C. The urea-derived deactivation and regeneration mechanisms of Cu-SAPO-34 were compared with those of anatase-supported catalysts.

关键词： SCR Urea Biuret Cu-SAPO-34 Deactivation

Pt@g-C3N4/CeO2 photocatalyst for the remediation of low concentration NOx at room temperature

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Progress in Natural Science:materials International 2020年第3期30卷 308-311页

作者： Yibin Liu yue ma Duan Weng Xiaodong Wu Zhichun Si Shenzhen International Graduate School Tsinghua University School of materials Science and Engineering Tsinghua University

Pt@g-C3N4/CeO2photocatalyst was prepared by calcination of g-C3N4/CeO2mixture followed by impregnating Pt. Under the irradiation of visible light with the presence of water vapor at room temperature, Pt@g-C3N4/CeO2showed significant performance for remediation of NOx. The deNOxmechanism was studied by modified in-situ FTIR. The results proved that NO was prone to adsorb on the surface of Pt@CeO2and oxidized to nitrite for storage. Then, the photoinduced hydrogen on Pt@g-C3N4component could diffuse into the vicinity of nitrite through the spillover effect of Pt and reacted with nitride to produce N2and H2O.

关键词： [email protected] /CeO2 Photocatalysis DeNOx Room temperature

Symmetry properties and widths of the filamentary structures in the Orion A giant molecular cloud

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Research in Astronomy and Astrophysics 2021年第8期21卷 23-45页

作者： Yu-Qing Zheng Hong-Chi Wang yue-Hui ma Chong Li Purple Mountain Observatory and Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210033China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China University of Chinese Academy of Sciences Beijing 100049China

We identify 225 filaments from an H2 column density map constructed using simultaneous 12CO,13CO and C18O(J=1-0) observations carried out as a part of the Milky Way Imaging Scroll Painting(MWISP) *** select 46 long filaments with lengths above 1.2 pc to analyze the filament column density *** divide the selected filaments into 397 segments and calculate the column density profiles for each *** symmetries of the profiles are *** proportion of intrinsically asymmetrical segments is 65.3%,and that of intrinsically symmetrical ones is 21.4%.The typical full width at half maximum(FWHM) of the intrinsically symmetrical filament segments is - 0.67 pc with the Plummer-like fitting,and - 0.50 pc with the Gaussian fitting,*** median FWHMs derived from the second-moment method for intrinsically symmetrical and asymmetrical profiles are - 0.44 and 0.46 pc,*** association exists between the filamentary structures and the YSOs in the region.

关键词： ISM:clouds ISM:individual objects(Orion A) ISM:structure stars:formation

Comparative transcriptome analysis of shortened fruit mutant in woodland strawberry (Fragaria vesca) using RNA-Seq

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Journal of Integrative Agriculture 2017年第4期16卷 828-844页

作者： WANG Shou-ming LI Wei-jia LIU yue-xue LI He ma yue ZHANG Zhi-hong College of Horticulture Shenyang Agricultural University Shenyang 110866 P.R. China

Genes controlling fruit appearance determine fruit shape and size. In ethylmethane sulfonate （EMS）-mutagenized lines of Fragaria vesca accession Yellow Wonder （YW）, two fruit shapes are observed： wild-type long fruit and mutated shortened fruit （sf）. In this study, we first characterized sf based on morphology, histology, cytology and physiology. The sf was identified as a gibberellin （GA）-deficient mutant, and four complementary DNA （cDNA） libraries separately constructed from flower buds and small green fruits of YW and sfwere sequenced to comparatively analyze transcriptome differences. A total of 29 differentially expressed GA pathway genes were identified by comparisons between YWl and sfl, and 28 differentially expressed GA pathway genes were identified between YW2 and sf2. In addition, the expression patterns of 45 differentially expressed genes were validated by quantificational real-time PCR （qRT-PCR）, and the results were highly concordant with the RNA-Seq results.＇ This transcriptome analysis provides valuable information for understanding the molecular mechanisms of fruit development of strawberry.

关键词： strawberry fruit shape transcriptome RNA-Seq differentially expressed gene

Isolation and Characterization of Transcriptionally Active Ty1-copia Retrotransposons in Fragaria × ananassa

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Agricultural Sciences in China 2010年第3期9卷 337-345页

作者： ma yue HE Ping SUN Hai-yue ZHAO Gui-ling DAI Hong-yan ZHANG Zhi-hong College of Horticulture Shenyang Agricultural University Shenyang 110866 P.R.China College of Forestry Shenyang Agricultural University Shenyang 110866 P.R.China

One possible mechanism suggested for somaclonal variation is the activation of transposable elements. The activation of retrotransposons by stresses and external changes is commonly observed in plants. In previous study, we isolated the reverse transcriptase （RT） gene sequences of Ty 1-copia retrotransposons from tissue culture strawberry （Fragaria x ananassa） plant, but not the transcriptionally active sequence. For further understanding the relationship between retrotransposon and somaclonal varation, in this study, we isolated the transcriptionally active RT gene sequences from strawberry plants subjected to different abiotic stresses. These retrotransposons were activated by spraying strawberry leaves with 2 mmol L^-1 salicylic acid （SA）, 50 mmol L^-1 methyl jasmonate （MeJA）, 50 mmol L^-1 abscisic acid （ABA）, 50 mmol L^-1 2,4- dichlorophenoxyacetic acid （2,4-D） or by inducing callus growth in 2 types of MS media： first medium supplemented with 0.5 mg L^-1 6-benzylaminopurine （6-BA）, 0.5 mg L^-1 gibberellic acid （GA3）, 1.0 mg L^-1 thidiazuron （TDZ）, and 0.1 mg L^-1 2,4-D, and the second medium supplemented with 0.5 mg L^-1 6-BA, 0.5 mg L^-1 GA3, 2.0 mg L^-1 TDZ, and 0.02 mg L^-1 indole butyric acid （1BA）. Analysis of gene sequences of 17 RTs revealed that none of them contained stop codons and/or indels disrupting the reading frame. These different stress-origin transcriptionally active RTs were remarkably similar to each other- FATEXP2-8 and FATEYS9-7 showed 100% sequence identity. Analysis of pylogenetic of these transcriptionally active RTs and the RT sequences from genome showed that there were close phylogenetic relationships of most of the transcriptionally active RTs. The results of this study have contributed to the background information necessary for future studies for evaluating the relationship between retrotransposons and somaclonal variation.

关键词： transcription activated callus culture Ty1-copia retrotransposons strawberry stress