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低功率圆柱形霍尔推进器实验特性研究

真空科学与技术学报 2024年第3期44卷 252-257页

作者：熊思维唐德礼李平川张帆陈满珍核工业西南物理研究院成都610200

随着航天技术的发展以及微小型卫星应用数量的不断增多,空间推进领域对低功率电力推进的需求越来越多。常见的环形霍尔推进器缩放至低功率时效率低下。圆柱形霍尔推进器具有较低的表面积与体积比,有利于通过磁镜效应更好地束缚电子以减... 详细信息

随着航天技术的发展以及微小型卫星应用数量的不断增多,空间推进领域对低功率电力推进的需求越来越多。常见的环形霍尔推进器缩放至低功率时效率低下。圆柱形霍尔推进器具有较低的表面积与体积比,有利于通过磁镜效应更好地束缚电子以减少通道壁处的粒子损失,从而减小通道的刻蚀和发热,这使得CHT对于低功率应用很有前景。文章进行低功率圆柱形霍尔推进器实验特性研究,在50 W功率范围内运行。实验得到了推进器在高电压、小气量、低电流工况下的工作特性、离子束特点等结果。实验表明:低功率圆柱形霍尔推进器工作电压在1000~2400 V之间,使用Ar体积流量在1.0~4.0 mL/min内,其比冲在218~1419 s,推力范围在0.118~0.78 mN,最大电流利用率为87%,最大推力效率为20.39%与先进霍尔推力器效率相当。同时发现在气体体积流量变大过程中,离子束出现强弱两种工作模式。

关键词：圆柱形霍尔推进器微型化阳极层模式转化

钼电极加热对放射性硼硅酸盐玻璃显微结构与性能影响研究

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核动力工程 2024年第S01期45卷 186-191页

作者：李箫波袁青青李平川程昌明唐德礼叶欣楠王伟核工业西南物理研究院成都610200 中核同创(成都)科技有限公司成都610200 中国核电工程有限公司北京100840 海南核电有限公司海口570100

硼硅酸盐玻璃被广泛应用于放射性废物的固化处理。在等离子体高温熔融系统中,含放射性核素的硼硅酸盐玻璃熔池底部和远离热源区域的玻璃体温度相对较低,熔池流动均匀性较差,极大阻碍出料过程。通过引入钼电极辅助加热熔池的方法,探究钼... 详细信息

硼硅酸盐玻璃被广泛应用于放射性废物的固化处理。在等离子体高温熔融系统中,含放射性核素的硼硅酸盐玻璃熔池底部和远离热源区域的玻璃体温度相对较低,熔池流动均匀性较差,极大阻碍出料过程。通过引入钼电极辅助加热熔池的方法,探究钼电极对放射性硼硅酸盐玻璃显微结构与性能的影响。实验结果表明,玻璃配方中Na_(2)O质量分数为10%时,能够避免出料玻璃体中析出杂质-钼酸钠和氧化钼;投入钼电极后,电极间玻璃液的初始大电阻特性使其释放大量焦耳热,熔池温度分布均匀性和流动性得到了改善,从而有效促进了出料过程,出料玻璃体重量提升约8.2%、密度提升约14.6%、抗压强度提升约13.6%。本文为开发一种废物容量大、运行时间长的等离子体高温熔融系统提供一定的解决思路。

关键词：热等离子体硼硅酸盐玻璃钼电极抗压强度

A Genetic-Algorithm-based Neural Network Approach for Radioactive Activity Prediction

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Nuclear Science and Techniques 2013年第6期24卷 12-16页

作者： WANG Lei TUO Xianguo YAN Yucheng liU Mingzhe CHENG Yi li pingchuan State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Southwest University of Science and Technology

In this paper,a genetic-algorithm-based artificial neural network(GAANN)model radioactivity prediction is proposed,which is verified by measuring results from Long Range Alpha Detector(LRAD).GAANN can integrate capabilities of approximation of Artificial Neural Networks(ANN)and of global optimization of Genetic Algorithms(GA)so that the hybrid model can enhance capability of generalization and prediction accuracy,*** this model,both the number of hidden nodes and connection weights matrix in ANN are optimized using genetic *** real data sets are applied to the introduced method and the results are discussed and compared with the traditional Back Propagation(BP)neural network,showing the feasibility and validity of the proposed approach.

关键词：神经网络方法遗传算法模型预测放射性人工神经网络活性逼近能力全局优化

An Integrated Workflow for DNA Methylation Analysis

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Journal of Genetics and Genomics 2013年第5期40卷 249-260页

作者： pingchuan li Feray Demirci Gayathri Mahalingam Caghan Demirci Mayumi Nakano Blake C.Meyers Department of Plant & Soil Sciences Delaware Biotechnology InstituteUniversity of DelawareNewarkDE 19711USA

The analysis of cytosine methylation provides a new way to assess and describe epigenetic regulation at a whole-genome level in many *** methylation has a demonstrated role in the genome stability and protection,regulation of gene expression and many other aspects of genome function and ***-seq is a relatively unbiased method for profiling the DNA methylation,with a resolution capable of measuring methylation at individual *** we describe,as an example,a workflow to handle DNA methylation analysis,from BS-seq library preparation to the data *** describe some applications for the analysis and interpretation of these *** laboratory provides public access to plant DNA methylation data via visualization tools available at our ＂Next-Gen Sequence＂ websites（http：//***）,along with small RNA,RNA-seq and other data types.

关键词： DNA methylation BS-seq Epigenetics

Degradome sequencing reveals endogenous small RNA targets in rice (Oryza sativa L. ssp. indica)

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Frontiers in Biology 2010年第1期5卷 67-90页

作者： Ming ZHOU lianfeng GU pingchuan li Xianwei SONG liya WEI Zhiyu CHEN Xiaofeng CAO State Key Laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Graduate School of the Chinese Academy of Sciences Yuquan RoadBeijing 100039China

MicroRNAs(miRNAs)and small interfering RNAs(siRNAs)regulate gene expression in *** miRNAs modulate their targets mainly via messenger RNA(mRNA)*** RNA(sRNA)targets have been extensively investigated in Arabidopsis using computational prediction,experimental validation,and degradome ***,small RNA targets are largely unknown in rice(Oryza sativa).Here,we report global identification of small RNA targets using high throughput degradome sequencing in the rice indica cultivar 93-11(Oryza sativa ***).One hundred and seventy-seven transcripts targeted by a total of 87 unique miRNAs were *** targets for the conserved miRNAs between Arabidopsis and rice,transcription factors comprise around 70%(58 in 82),indicating that these miRNAs act as masters of gene regulatory nodes in *** contrast,non-conserved miRNAs targeted diverse genes which provide more complex regulatory *** addition,5 AUXIN RESPONSE FACTORs(ARFs)cleaved by the TAS3 derived ta-siRNAs were also detected.A total of 40 sRNA targets were further validated via RNA ligasemediated 5′rapid amplification of cDNA ends(RLM 5′-RACE).Our degradome results present a detailed sRNAtarget interaction atlas,which provides a guide for the study of the roles of sRNAs and their targets in rice.

关键词： Degradome miRNA ta-siRNA small RNA targets rice

Fine-Tuning of MiR528 Accumulation Modulates Flowering Time in Rice

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Molecular Plant 2019年第8期12卷 1103-1113页

作者： Rongxin Yang pingchuan li Hailiang Mei Dong Wang Jing Sun Chao Yang lili Hao Shouyun Cao Chengcai Chu Songnian Hu Xianwei Song Xiaofeng Cao State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing) Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of SciencesBeijing 100101China Key Laboratory of Molecular Biology and Gene Engineering in Jiangxi Province College of Life ScienceNanchang UniversityNanchangJiangxi 330031China University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Molecular Plant Sciences Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China

In plants,microRNA (miRNA) functions in the post-transcriptional repression of target mRNAs have been well ***,the mechanisms regulating the accumulation of miRNAs remain poorly ***,we report that distinct mechanisms regulate accumulation of a monocot-specific miRNA,rice (Oryza sativa) *** the transcriptional level,miR528 accumulated to higher levels in older plants than in young seedlings and exhibited aging-modulated gradual accumulation and diurnal rhythms in leaves;at the post-transcriptional level,aging also modulated miR528 levels by enhancing pri-miR528 *** *** found that miR528 promotes rice flowering under long-day conditions by targeting RED AND FAR-RED INSENSITIVE2 (OsRFI2).Moreover,natural variations in the MIR528 promoter region caused differences in miR528 expression among rice varieties,which are correlated with their different binding affinities with the transcription factor OsSPL9 that activates the expression of *** together,our findings reveal rice plants have evolved sophisticated modes fine-tuning miR528 levels and provide insight into the mechanisms that regulate MIRNA expression in plants.

关键词： miRNA OsSPL9 Alternative splicing Post-transcriptional regulation Natural variation Flowering

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常见农药的微生物降解研究现状

云南化工 2024年第8期51卷 15-18页

作者：夏绍辉王静李平川周韵扬李元春刘志搏张洋蒋鹏徐安益云南农业大学云南昆明650201

处理残留农药是目前环境保护中亟待解决的问题。相比传统物理或化学降解法处理残留农药,微生物降解法具有高效和环保等特点,被作为农药降解的重要手段。综述了常见残留农药微生物降解机理,浅析了微生物降解不同种类农药(氨基甲酸酯、有... 详细信息

处理残留农药是目前环境保护中亟待解决的问题。相比传统物理或化学降解法处理残留农药,微生物降解法具有高效和环保等特点,被作为农药降解的重要手段。综述了常见残留农药微生物降解机理,浅析了微生物降解不同种类农药(氨基甲酸酯、有机氯、有机磷、拟除虫菊酯)中的研究进展,探讨了微生物降解农药所存在的不足,旨在为微生物技术修复不同类型残留农药的实际应用提供参考。

关键词：农药降解残留农药微生物降解微生物修复

Preliminary Results of the Seismicity Monitoring Experiment around the 2019 Mw5.4 Earthquake Epicenter in the Central South China Sea Basin

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Journal of Earth Science 2024年第1期35卷 212-220页

作者： Wenfei Gong Aiguo Ruan Xiongwei Niu Zhenjie Wang pingchuan Tan Xiaodong Wei Wei Wang Zhengyi Tong liqun Cheng Fansheng Kong Shaoping Lu Jianke Fan Weiwei Ding Jinyao Gao Chunguo Yang Jiabiao li School of Oceanography Shanghai Jiaotong UniversityShanghai 200240China Key Laboratory of submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Zhejiang Earthquake Administration Hangzhou 310013China School of Earth Sciences Zhejiang UniversityHangzhou 310027China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China School of Earth Sciences and Engineering Sun Yat-sen UniversityZhuhai 519082China Institute of Oceanology Chinese Academy of SciencesQingdao 266071China

On September 5,2019,a moderate earthquake of Mw5.4 unexpectedly occurred in the apparently quiescent central basin of the South China *** immediately carried out a seismicity monitoring experiment around the epicenter by using broadband ocean bottom seismometers(OBS)for the following three scientific *** first is knowing the earthquake seismogenic mechanism,fault structure and further *** second is finding the role of the residual spreading ridge playing in earthquake processes and further revealing the deep structures of the ridge directional turning *** third is confirming the existence and significance of the so called“Zhongnan fault”.This paper reports the preliminary results of the first phase *** OBSs were deployed for seismicity monitoring with a duration of 288 days,but only three were ***-earthquakes were firstly detected by an automatic seismic phase picking algorithm and then were verified by analyzing their seismic phases and time-frequency characteristics in detail.A total of 21,68 and 89 microearthquakes were picked out from the three OBSs respectively within the distance of 30 *** dominant frequency of these micro-earthquakes is 12-15 Hz,indicating tectonic *** the first two months after the mainshock the seismicity was relatively stronger,and micro-earthquakes were still occurring occasionally till the end of observation,indicating the epicenter area is *** used Match&Locate method to locate 57 micro-earthquakes *** spatial distribution shows that the seismicity is developed mainly along the NE direction roughly parallel to the residual ridge with depth variations between 10-20 km.

关键词： South China Sea microseismic monitoring earthquakes fault broadband OBS

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圆柱形阳极层霍尔推力器的内磁极刻蚀研究

真空科学与技术学报 2018年第8期38卷 708-718页

作者：赵杰唐德礼李平川耿少飞核工业西南物理研究院成都610041 成都理工大学工程技术学院乐山614007

本文重点研究引起圆柱形阳极层霍尔推力器的内磁极刻蚀的入射离子能量和入射角分布,仿真中考虑入射离子能量和入射角分布大小的变化,进而得到相应的刻蚀速率。由仿真结果可知,放电电压400 V,阳极表面磁场强度175×10^(-4)T,中心最大刻... 详细信息

本文重点研究引起圆柱形阳极层霍尔推力器的内磁极刻蚀的入射离子能量和入射角分布,仿真中考虑入射离子能量和入射角分布大小的变化,进而得到相应的刻蚀速率。由仿真结果可知,放电电压400 V,阳极表面磁场强度175×10^(-4)T,中心最大刻蚀速率为3×10^(-9)m/s。磁场提高到205×10^(-9)T时,中心附近刻蚀速率增加到原来的1.3倍左右,边沿处的刻蚀速率基本相同。在175×10^(-9)T的磁场强度时,把放电电压从400提高到600 V时,中心附近的刻蚀速率从3×10^(-9)提高到12.1×10^(-9)m/s,刻蚀速率增加了4倍多。此仿真结果与150 h的实验结果一致。此研究方法和结果有助于圆柱形阳极层霍尔推力器的设计和寿命评估工作。

关键词：刻蚀速率推力器等离子体入射能量入射角余弦值