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Microsystems & Nanoengineering 2023年第2期9卷 47-57页

作者： yunfei Gao Minkan Chen Zhipeng Wu Lei yao Zhihao Tong Songsong Zhang yuandong Alex Gui Liang lou School of Microelectronics Shanghai UniversityShanghai 201800China Shanghai IndustrialμTechnology Research Institute Shanghai 201899China

Transit-time ultrasonic flowmeters(TTUFs)are among the most widely used devices for flow ***,traditional TTUFs are usually based on a bulk piezoelectric transducer,which limits their application in small-diameter *** this paper,we developed a miniaturized TTUF based on scandium-doped aluminum nitride(ScAIN)piezoelectric micromachined ultrasonic transducers(PMUTs).The proposed TTUF contains two PMUT-based transceivers and a T-type *** PMUTs contain 13×13 square cells with dimensions of 2.8×2.8 mm^(2).To compensate for the acoustic impedance mismatch with liquid,a layer of polyurethane is added to the surface of the PMUTs as a matching *** PMUT-based transceivers show good transmitting sensitivity(with 0.94 MPaN surface pressure)and receiving sensitivity(1.79 mV/kPa)at a frequency of 1 MHz in ***,the dimensions of the Ttype channel are optimized to achieve a measurement sensitivity of 82 ns/(m/s)and a signal-to-noise ratio(SNR)better than 15 ***,we integrate the fabricated PMUTs into the TDC-GP30 *** experimental results show that the developed TTUF provides a wide range of flow measurements from 2 to 300 L/h in a channel of 4 mm diameter,which is smaller than most reported *** accuracy and repeatability of the TTUF are within 0.2%and 1%,*** proposed TTUF shows great application potential in industrial applications such as medical and Chemical applications.

关键词： piezoelectric flow dimensions

Mechanical Properties and Fracture Mechanism of a Glass Fiber Reinforced Polypropylene Composites

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Journal of Wuhan University of Technology(Materials Science) 2020年第3期35卷 629-634页

作者： lou Shumei yIN Wenying MA Xiaodong yUAN Jianjun WANG Qingbiao Department of Mechanical and Electrical Engineering Shandong University of Science and TechnologyTai'an 271019China National Engineering Laboratory for Coalmine Backfilling Mining Shandong University of Science and TechnologyTai'an 271019Chi-na Department of Resource and Civil Engineering Shandong University of Science and TechnologyTai'an271019China

To study the effect of some parameters, such as, length and fraction of glass fiber (GF), and the fraction of maleic anhydride grafted polypropylene (PP-g-MAH), on the mechanical properties of glass fiber reinforced polypropylene (GF/PP) composites, tensile tests, bending tests and impact tests were conducted. Scanning electron microscope (SEM) was used to characterize the fracture mechanisms of the composites. The results show that, compared with 3 mm GF, 9 mm GF can significantly improve the strength of the composite better. Addition of PP-g-MAH, a kind of grafting agent, into the PP-30% LGF composite can result in a better mechanical properties because of the strengthening of the bonding interface between the matrix and the fiber. When the mass fraction of GF is 30% and the PP-g-MAH fraction is 6%, the mechanical properties of the composite are the best.

关键词： GF/PP mechanical properties maleic anhydride grafted polypropylene(PP-g-MAH) fracture mechanisms

Development of a Mengla virus minigenome and comparison of its polymerase complexes with those of other filoviruses

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Virologica Sinica 2024年第3期39卷 459-468页

作者： Shi-Zhe Xie ke yao Bei Li Cheng Peng Xing-lou yang Zheng-Li Shi State Laboratory of Virology Wuhan Institute of VirologyChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China yunnan key Laboratory of Biodiversity Information Kunming Institute of ZoologyChinese Academy of SciencesKunming650201China Hubei Jiangxia Laboratory Wuhan430200China

Ebola virus(EBOV)and Marburg virus(MARV),members of the Filoviridae family,are highly pathogenic and can cause hemorrhagic fevers,significantly impacting human *** are considered reservoirs of these viruses because related filoviruses have been discovered in ***,due to the requirement for maximum containment laboratories when studying infectious viruses,the characterization of bat filoviruses often relies on pseudoviruses and minigenome *** this study,we used RACE technology to sequence the 30-leader and 50-trailer of Mengla virus(MLAV)and constructed a *** to MARV,the transcription activities of the MLAV minigenome are independent of *** further assessed the effects of polymorphisms at the 50 end on MLAV minigenome activity and identified certain mutations that decrease minigenome reporter efficiency,probably due to alterations in the RNA secondary *** reporter activity upon recombination of the 30-leaders and 50-trailers of MLAV,MARV,and EBOV with those of the homologous or heterologous minigenomes was compared and it was found that the polymerase complex and leader and trailer sequences exhibit intrinsic ***,we investigated whether the polymerase complex proteins from EBOV and MARV support MLAV minigenome RNA synthesis and found that the homologous system is more efficient than the heterologous *** efficiently inhibited MLAV as well as EBOV *** summary,this study provides new information on bat filoviruses and the minigenome will be a useful tool for high-throughput antiviral drug screening.

关键词： Bat filovirus Mengla virus(MLAV) Minigenome Replication Antiviral drug screening

The Impact of Urban Expansion on Plant Diversity Change in karst Regions of Southwest China

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Chinese Geographical Science 2022年第3期32卷 493-505页

作者： yANG Shengtian LI Chaojun lou Hezhen LUO ya WANG Pengfei ZHANG Jun LI Xi WU Xijin College of Water Sciences Beijing Normal UniversityBeijing 100875China College of Geography and Environmental Sciences Guizhou Normal UniversityGuiyang 550001China

Biodiversity is vital for the integrity and stability of ecosystems and sustainable *** regions of Southwest China is featured for undulating and broken karst terrain as well as high plant *** use changes induced by the growing population and expanding human settlement have threatened biodiversity preservation in this ***,the impact of urban expansion on plant diversity remains unclear *** study focuses on how expanding countryside landscapes affect the recovery rate of plant diversity and demonstrate how urban expansion affects plant diversity conservation in karst regions of Southwest *** situ biodiversity investigations and multisource remote sensing images were combined to analyze the role of human settlement evolution in the conservation of plant diversity using descriptive statistics and regression *** vehicle images,historical aerial photographs,and long-term remote sensing images were used to observe the human settlement pattern changes over 40 yr and found that plant diversity is restored faster in countryside ecosystems than in island ecosystems restricted by ***,however,contribute the most to plant diversity conservation in both *** the forest area is stable during urban expansion,massive forest patches play an essential role in plant diversity *** lands and grasslands shrank but with a fragmenting trend,which was conducive to preserving plant diversity,whereas increased and regularized large patches of built-up areas were not beneficial to plant ***,forest protection should be prioritized to coordinate future socioeconomic development and plant diversity conservation in karst and broader ***,large built-up patches should be limited,and the irregularity should be improved during urban *** shaped cultivated land and grassland were suggested to promote biological information exchanges as landscape corridors.

关键词： plant diversity change urban expansion countryside landscapes karst regions remote sensing China

Facile and efficient one-pot synthesis of 2-arylbenzoxazoles using hydrogen tetrachloroaurate as catalyst under oxygen atmosphere

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第6期10卷 472-478页

作者： yun-kui LIU Da-jie MAO Shao-jie lou Jian-qiang QIAN Zhen-yuan XU State key Laboratory Breeding Base of Green Chemistry-Synthesis Technology Zhejiang University of Technology Hangzhou 310014 China

In this paper, we presented a novel method for the facile and efficient one-pot synthesis of 2-arylbenzoxazoles, which were directly synthesized from 2-aminophenol and aldehydes catalyzed by hydrogen tetrachloroaurate (HAuCl4·4H2O) under an oxygen atmosphere with anhydrous tetrahydrofuran (THF) as solvent or in solvent-free condition. The results show that this method could bring excellent yields as high as 96%. THF was proven to be the best choice among several solvents screened and the reaction was tolerated with a variety of aromatic aldehydes possessing electron-donating or withdrawing groups. The advantages of the present method lie in catalytic process using economic and environmentally benign dioxygen as oxidant.

关键词： 2-Arylbenzoxazoles 2-Aminophenol Aldehydes Hydrogen tetrachloroaurate One-pot synthesis

Characterization of the first prototype CMOS pixel sensor developed for the CEPC vertex detector

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Radiation Detection Technology and Methods 2019年第3期3卷 222-230页

作者： L.J.Chen H.B.Zhu X.C.Ai M.Fu R.kiuchi y.Liu Z.A.Liu X.C.lou y.P.Lu Q.Ouyang X.Shi J.Tao k.Wang N.Wang C.F.yang y.Zhang y.Zhou institute of high energy physics chinese academy of sciences19b yuquan roadshijingshan districtbeijingchina university of chinese academy of sciences no.19(a)yuquan roadshijingshan districtbeijingchina state key laboratory of particle detection and electronics 19b yuquan roadshijingshan districtbeijingchina deutsches elektronen-synchrotron(desy) notkestraße 8522607 hamburggermany university of science and technology of china no.96jinzhai road baohe districthefeianhuichina ocean university of china no.238 songling roadqingdao 266100china

Purpose CMOS pixel sensor has become extremely attractive for future high-performance tracking *** has been proposed for the vertex detector at the Circular Electron Positron Collider,which will allow precision measurements of the properties of the Higgs *** meet the stringent requirements for low power consumption,it is necessary to optimize the pixel sensor diode geometry to reach a high charge-over-capacitance ratio that allows reduction in analog power *** Collection electrode size and footprint are two critical elements in sensor diode geometry and have deciding impacts on the charge collection performance.A prototype CMOS pixel sensor,named JadePix-1,has been developed with pixel sectors implemented with different electrode sizes and footprints,and its charge collection performance has been characterized with radioactive *** Charge-to-voltage conversion gains for pixel sectors under test have been calibrated with low-energy *** results have been obtained for equivalent noise charge(below 10e−),charge collection efficiency(around 40%),charge-over-capacitance ratio(above 0.015 V)and signal-to-noise ratio(higher than 55).Conclusion Small collection electrode size and large footprint are preferred to achieve high charge-over-capacitance ratio that promises low analog power *** studies on sensor performance before and after irradiation,combined with this work,will conclude the diode geometry optimization.

关键词： CMOS pixel sensor CEPC Power consumption Diode geometry Charge-over-capacitance ratio

Breeding design in wheat by combining the QTL information in a GWAS panel with a general genetic map and computer simulation

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The Crop Journal 2023年第6期11卷 1816-1827页

作者： Xiaobo Wang Weiwei Mao yongfa Wang Hongyao lou Panfeng Guan yongming Chen Huiru Peng Jiankang Wang State key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Frontiers Science Center for Molecular Design Breeding(MOE) Key Laboratory of Crop Heterosis and UtilizationKey Laboratory of Crop Genetic ImprovementCollege of Agronomy and BiotechnologyChina Agricultural UniversityBeijing 100193China Hainan yazhou Bay Seed Laboratory Sanya 572025HainanChina National Nanfan Research Institute(Sanya) Chinese Academy of Agricultural SciencesSanya 572024HainanChina

A large amount of genome-wide association study(GWAS)panels together with quantitative-trait locus(QTL)information associated with breeding-targeted traits have been described in wheat(Triticum aestivum L.).However,the application of mapping results from a GWAS panel to conventional wheat breeding remains a *** this study,we first report a general genetic map which was constructed from 44 published linkage *** permits the estimation of genetic distances between any two genetic loci with physical map positions,thereby unifying the linkage relationships between QTL,genes,and genomic markers from multiple genetic ***,we describe QTL mapping in a wheat GWAS panel of 688 accessions,identifying 77 QTL associated with 12 yield and grain-quality *** these QTL have known physical map positions,they could be mapped onto the general ***,we present a design approach to wheat breeding by using known QTL information and computer *** crosses between parents in the GWAS panel may be evaluated by the relative frequency of the target genotype,trait correlations in simulated progeny populations,and genetic gain of selected *** is possible to simultaneously improve yield and grain quality by suitable parental selection,progeny population size,and progeny selection *** the design approach will allow identifying the most promising crosses and selection schemes in advance of the field experiment,increasing predictability and efficiency in wheat breeding.

关键词： Wheat breeding Breeding design GWAS panel General genetic map Computer simulation

The bHLH Transcription Factors MyC2, MyC3, and MyC4 Are Required for Jasmonate-Mediated Inhibition of Flowering in Arabidopsis

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Molecular Plant 2017年第11期10卷 1461-1464页

作者： Houping Wang yang Li Jinjing Pan Dengji lou yanru Hu Diqiu yu key Laboratory of Tropical Plant Resources and Sustainable Use Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Kunming Yunnan 660223 China University of Chinese Academy of Sciences Beijing 100049 China

Dear Editor,In plants, the floral transition is flexibly controlled by various environmental conditions and endogenous developmental cues. In Arabidopsis, six major flowering pathways respond to changes in these factors （Fornara et al., 2010）. The photoperiod, vernalization, and ambient pathways monitor exogenous signals from the environment such as day length, minimum winter temperature, and ambient temperature （Fornara et al., 2010）. By contrast, the autonomous, gibberellin, and age pathways respond to endogenous cues linked to developmental status （Fornara et al., 2010）. Accumulating evidence indicates that the six flowering pathways converge in a network to regulate floral integrator genes FLOWERING LOCUS T （FT）, TWIN SISTER OF FT （TSF）, and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 （Fornara et al., 2010）.

关键词： The bHLH Transcription Factors MyC2 MyC3 MyC4 Are Required for Jasmonate-Mediated Inhibition of Flowering in Arabidopsis

Magnetized Power-Law Disks

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Magnetized Power-Law Disks

Acoustic emission-based numerical simulation of tectonic stress field for tectoclase prediction in shale reservoirs of the northern Guizhou area, China

中国天文学会星系分会2004年学术年会

作者： yue Shen, THCA Advisor: Prof. y.-Q. lou

来源： cnki会议评论

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Energy Geoscience 2022年第4期3卷 436-443页

作者： Zhonghu Wu Motian Tang yujun Zuo yili lou Wentao Wang Hao Liu Wenjibin Sun College of Civil Engineering Guizhou UniversityGuiyangGuizhou550025China School of Qilu Transportation Shandong UniversityJinanShandong250002China Geotechnical and Structural Engineering Research Center Shandong UniversityJinanShandong250061China Mining College Guizhou UniversityGuiyangGuizhou550025China

Natural fractures,like tectoclases,are essential in the formation of shale gas reservoirs and have been the focus of study for shale gas *** provide most storage space for gas and are largely controlled by the paleo-tectonic stress field in shale reservoirs of the Niutitang Formation,northern Guizhou area,*** accurate prediction of the development and distribution of tectoclases in the reservoirs is of great significance to exploring and developing shale gas sweet spots in the *** on geological structure evolution and fracture characterization,this study is focused on factors that control the fracture development in the Niutitang Formation shale reservoirs in northern Guizhou through characterization and modeling of geomechanisms and tectonic movements.A geomechanical model is formulated for the shale reservoirs against the geological background of the *** this basis,the fractures are predicted by using the acoustic emission *** simulation results show that the development and distribution of tectoclase is controlled by fault zones,some of which have no obvious turning points with tectoclase in the middle sections being more developed and fragmented than those at the two *** of these have obvious S-shaped turning points where tectoclases are the most developed and fragmented.

关键词： Shale reservoir Tectonic stress field Numerical simulation Tectoclase Acoustic emission