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Electrochemical micromachining of microgroove arrays on phosphor bronze surface for improving the tribological performance

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Chinese Journal of Aeronautics 2018年第7期31卷 1609-1618页

作者： Xuan ZHOU Ningsong QU Zhibao HOU gai ZHAO College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology Nanjing 210016 China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016 China

A high friction coefficient and a low wear rate of contacted surfaces are essential elements to friction pairs between the stator and the rotor in ultrasonic motors. It has been shown that surface textures have a significant effect on improving the tribological performance of friction *** this paper, microgroove arrays are introduced to the stator surface for improving the tribological performance of friction pairs between the stator and the rotor in ultrasonic motors. Microgrooves were fabricated on a phosphor bronze surface by through-mask electrochemical micromachining（TMEMM）. Parameters, namely, the electrolyte inlet pressure, applied voltage, pulse duty cycle,and frequency, were varied to investigate their influences on the dimensions and morphology of the microgrooves. Results showed that the width and depth of the microgrooves were strongly affected by the applied voltage and frequency, while the morphology of the microgrooves was dependent on the electrolyte inlet pressure and the pulse duty cycle. Compared with a smooth surface, the friction coefficient increased from 0.245 to 0.334 and less abrasion was obtained when a surface was textured with microgrooves of which the width and depth were 185.6 and 57.6 lm,respectively. Microgroove arrays might play an important role in enhancing the performance of ultrasonic motors.

关键词： Friction coefficient Microgrooves Through-mask electrochemical micromachining Ultrasonic motors Wear

Knudsen cell and smog chamber study of the heterogeneous uptake of sulfur dioxide on Chinese mineral dust

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Journal of Environmental Sciences 2014年第12期26卷 2423-2433页

作者： Li Zhou Weigang Wang Yanbo gai Maofa Ge Beijing National Laboratory for Molecular Science (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of Chemistry Chinese Academy of Sciences Beijing National Laboratory for Molecular Science (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesPeking University

The heterogeneous uptake processes of sulfur dioxide on two types of Chinese mineral dust（Inner Mongolia desert dust and Xinjiang sierozem） were investigated using both Knudsen cell and smog chamber system. The temperature dependence of the uptake coefficients was studied over a range from 253 to 313 K using the Knudsen cell reactor, the initial uptake coefficients decreased with the increasing of temperature for these two mineral dust samples, whereas the steady state uptake coefficients of the Xinjiang sierozem increased with the temperature increasing, and these temperature dependence functions were obtained for the first time. In the smog chamber experiments at room temperature, the steady state uptake coefficients of SO2 decreased evidently with the increasing of sulfur dioxide initial concentration from 1.72 × 1012 to 6.15 × 1012mol/cm3. Humid air had effect on the steady state uptake coefficients of SO2 onto Inner Mongolia desert *** about the understanding of the uptake processes onto mineral dust samples and the environmental implication were also discussed.

关键词： Mineral dust Sulfur dioxide Uptake coefficient Temperature dependence

Application of Molecular Markers Linking to Cytoplasmic Male Sterile Loci to Assist Maintainer Line Selection and Their Selection Efficiency in Welsh Onion (Allium fistulosum L.)

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Agricultural Sciences in China 2010年第11期9卷 1571-1576页

作者： gai Shu-peng MENG Xiang-dong College of Life Science Qingdao Agricultural University Qingdao 266109 P.R.China College of Horticulture Shandong Agricultural University Tai ＇an 271018 P.R. China

Cytoplasmic male sterility exists widely in most natural populations of welsh onion （Alliumfistulosum L.）, which makes it possible to breed out many male sterile lines for heterosis utilization. Unfortunately, the breeding of cytoplasmic male sterility in welsh onion has a little progress due to the limitation of its biological characteristic and traditional selection approach. To study the feasibility and the efficiency of utilizing marker assisted selection for male sterile lines in welsh onion, one SCAR marker, SCS13, and one RAPD marker, S2002400, which could distinguish between N and S cytoplasm in several welsh onion cultivars, were identified. The two markers were then confirmed by Southern blotting, and used to screen the N or S cytoplasm of individual plants in seven welsh onion cultivars in this study. Male sterile and fertile plants were evaluated by aceto-carmine dying. The frequency of N-cytoplasmic plants and maintainer genotype was calculated in the seven open populations of welsh onion. The minimum number of plants needed to identify a maintainer was evaluated to be 95% reliable. Results showed that 20 to 80% decrease of crosses and self-crosses for identifying a maintainer genotype could be achieved by the marker-assisted selection compared with traditional selection method. It was proved that the molecular markers could precisely identify cytoplasmic types individually, performed by one generation of cross and two generations of testcrosses and self-crosses. Finally, several maintainer genotype plants were selected with the help of the two markers in the seven cultivars. The screened markers could assist and accelerate sterile and maintainer lines selection with less labor and cost.

关键词： Alliumfistulosum L. CMS (cytoplasmic male sterility) markers-assisted selection molecular marker efficiency

Insights of section-wide pan-genome into hybrid potato breeding

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Science China(Life Sciences) 2022年第10期65卷 2125-2127页

作者： gai Huang Yuxian Zhu State Key Laboratory of Protein and Plant Gene Research School of Life SciencesPeking UniversityBejing 100190China Institute for Advanced Studies Wuhan UniversityWuhan430072China

Crop improvement for high yield,good nutrition,and strong resistance is key to feed the growing population of the *** efforts with the aid of genomics information have dramatically shortened the time for new crop varieties development(Huang et al.,2021;Huang and Zhu,2021;Yu et al.,2021).To date,pan-genomics studies have been reported for many important crops(Gao et al.,2019;Chen et al.,2022.)

关键词： breeding crops Crop

Identification and expression patterns of alcohol dehydrogenase genes involving in ester volatile biosynthesis in pear fruit

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Journal of Integrative Agriculture 2017年第8期16卷 1742-1750页

作者： QIN gai-hua QI Xiao-xiao QI yong-jie GAO Zheng-hui YI Xing-kai PAN Hai-fa XU Yi-liu Horticultural Research Institute Anhui Academy of Agricultural SciencesHefei 230031P.R.China Anhui Key Laboratory of Genetic Improvement and Ecophysiology of Horticultural Crop Hefei 230031P.R.China College of Agriculture Medicine and HealthAnhui Radio and Television UniversityHefei 230022P.R.China

Alcohol dehydrogenase （ADH） catalyzes the interconversion of aldehydes and their corresponding alcohols, and is a key enzyme in volatile ester biosynthesis. However, little is known regarding ADH and ADH encoding genes （ADHs） in pear. We identified 8 ADHs in the pear＇s genome （PbrADHs） by multiple sequences alignment. The PbrADHs were highly ho- mologous in their coding regions, while were diversiform in structure. 9 introns were predicted in PbrADH3-PbrADH8, while 8 introns, generated through exon fusion and intron loss, were predicted in PbrADH1 and PbrADH2. To study the genetic regulation underlying aroma biogenesis in pear fruit, we determined the PbrADH transcripts, ADH activities and volatile contents of fruits during ripening stage for Nanguoli and Dangshansuli, two cultivars having different aroma characteristics. ADH activity was strongly associated with the transcription of ADH~ in the two cultivars during fruit ripening stage. The higher ester content paralleling to a higher ADH activity was detected in Nanguoli than in Dangshansuli, so it is induced that the lower ester content in Dangshansuli fruit may be the result of weak ADH activity. The present study revealed that total ADH activity and volatile ester production correlated with increased PbrADHstranscript levels. PbrADH6 may contribute to ADH activity catalyzing aldehyde reduction and ester formation in pear fruit.

关键词： alcohol dehydrogenase ester volatile gene expression pear

A Malvaceae-specific miRNA targeting the newly duplicated GaZIP1L to regulate Zn^(2+)ion transporter capacity in cotton ovules

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Science China(Life Sciences) 2021年第3期64卷 339-351页

作者： Xingpeng Wen gai Huang Chenyu Li Yuxian Zhu Institute for Advanced Studies Wuhan UniversityWuhan 430072China State Key Laboratory of Protein and Plant Gene Research School of Life SciencesPeking UniversityBeijing 100871China

MicroRNAs(miRNAs)play critical roles in regulating gene expression in plants,yet their functions underlying cultivated diploid Gossypium arboreum cotton ovule development are largely ***,we acquired small RNA profiles from *** ovules and fibers collected at different growth stages,and identified 46 novel miRNAs that accounted for 23.7%of all miRNAs in *** reported in the latest plant sRNA *** analysis of 84(including 38 conserved)differentially expressed *** miRNAs,we detected 215 putative protein-coding genes in 26 biological processes as their potential targets.A Malvaceae-specific novel miRNA named gar-miRN44 was found to likely regulate cotton ovule growth by targeting to a newly duplicated Zn^(2+)ion transporter gene *** cotton ovule development,gar-miRN44 transcript level decreased sharply after 10 to 15 days post-anthesis(DPA),while that of the GaZIP1L increased significantly,with a concomitant increase of Zn^(2+)ion concentration in late ovule developmental *** dynamics simulation and ion absorption analysis showed that GaZIP1L has stronger Zn2+ion binding ability than the original GaZIP1,indicating that the newly evolved GaZIP1L may be more suitable for maintaining high Zn2+ion transport capacity that is likely required for cotton ovule growth via enhanced cellulose synthase *** systematic miRNA profiling in *** and characterization of gar-miRN44 not only contribute to the understanding of miRNA function in cotton,but also provide potential targets for plant breeding.

关键词： gar-miRN44 Malvaceae GaZIP1L Zn^(2+)ion transport cotton ovule development

Sustainable plant disease control: biotic information flow and behavior manipulation

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Science China(Life Sciences) 2019年第12期62卷 1710-1713页

作者： Yuying Xia gai Huang Yuxian Zhu Institute for Advanced Studies Wuhan UniversityWuhan 430072China State Key Laboratory of Protein and Plant Gene Research College of Life SciencesPeking UniversityBeijing 100871China

Crop pests and diseases are a major threat to agricultural production *** utilize massive quantities of chemical pesticides,herbicides,and fungicides for secure crop *** the extensive use of pesticides and other chemicals,serious problems regarding human and animal poisoning,agricultural product pollution,and ecological and environmental damage can no longer be ignored(Toju et al.,2018).Therefore,there is an urgent need to develop new strategies and technologies by employing basic research on information flow and cross-talk among crops,insects,and pathogenic microorganisms for sustainable *** recent years,great progress has been made in understanding the relationship between plants and other organisms to ensure the safety of food production in China and worldwide.

关键词： Sustainable pesticides utilize

Medical Image Segmentation using PCNN based on Multi-feature Grey Wolf Optimizer Bionic Algorithm

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Journal of Bionic Engineering 2021年第3期18卷 711-720页

作者： Xue Wang Zhanshan Li Heng Kang yongping Huang Di gai College of Computer Science and Technology Jilin UniversityChangchun 130012China Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin UniversityChangchun 130012China ZICT Technology Co. Ltd.Shenzhen 518063China

Medical image segmentation is a challenging task especially in multimodality medical image *** this paper,an improved pulse coupled neural network based on multiple hybrid features grey wolf optimizer(MFGWO-PCNN)is proposed for multimodality medical image ***,a two-stage medical image segmentation method based on bionic algorithm is presented,including image fusion and image *** image fusion stage fuses rich information from different modalities by utilizing a multimodality medical image fusion model based on maximum energy *** the stage of image segmentation,an improved PCNN model based on MFGWO is proposed,which can adaptively set the parameters of PCNN according to the features of the *** modalities of FLAIR and TIC brain MRIs are applied to verify the effectiveness of the proposed MFGWO-PCNN *** experimental results demonstrate that the proposed method outperforms the other seven algorithms in subjective vision and objective evaluation indicators.

关键词： grey wolf optimizer pulse coupled neural network bionic algorithm medical image segmentation

Extending homogeneous fluidization flow regime of Geldart-A particles by exerting axial uniform and steady magnetic field

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Chinese Journal of Chemical Engineering 2024年第1期65卷 169-177页

作者： Qiang Zhang Wankun Liu Hengjun gai Quanhong Zhu College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China School of Chemical&Environmental Engineering China University of Mining&Technology-BeijingBeijing 100083China

The homogeneous/particulate fluidization flow regime is particularly suitable for handling the various gas–solid contact processes encountered in the chemical and energy *** work aimed to extend such a regime of Geldart-A particles by exerting the axial uniform and steady magnetic *** the action of the magnetic field,the overall homogeneous fluidization regime of Geldart-A magnetizable particles became composed of two parts:inherent homogeneous fluidization and newly-created magnetic *** the former remained almost unchanged whereas the latter became broader as the magnetic field intensity increased,the overall homogeneous fluidization regime could be extended *** for Geldart-A nonmagnetizable particles,certain amount of magnetizable particles had to be premixed to transmit the magnetic *** others,the mere addition of magnetizable particles could broaden the homogeneous fluidization *** added content of magnetizable particles had an optimal value with smaller/lighter ones working *** added magnetizable particles might raise the ratio between the interparticle force and the particle *** the magnetic field was exerted,the homogeneous fluidization regime was further expanded due to the formation of magnetic stabilization flow *** more the added magnetizable particles,the better the magnetic performance and the broader the overall homogeneous fluidization ***/lighter magnetizable particles were preferred to maximize the magnetic performance and extend the overall homogeneous fluidization *** phenomenon could be ascribed to that the added magnetizable particles themselves became more Geldart-A than-B type as their density or size decreased.

关键词： Fluidized-bed Fluidization Geldart-A particles Flow regimes Extend Magnetic stabilization