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Coupling plasma plume of a low-power magnetically shielded Hall thruster with a hollow cathode

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Chinese Journal of Aeronautics 2020年第12期33卷 3018-3026页

作者： Guangchuan ZHANG Junxue REN Wei LIANG ning ouyang Chao LU Haibin TANG School of Space and Environment Beihang UniversityBeijing 100083China School of Astronautics Beihang UniversityBeijing 100083China Shanghai Institute of Space Propulsion Shanghai 201112China Key Laboratory of Spacecraft Design Optimization&Dynamic Simulation Technologies Ministry of EducationBeijing 100083China Laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100083China

The coupling region of a Hall thruster with a hollow cathode is the region between the cathode and the thruster *** characteristics of plasma in that region are complicated and strongly associated with the thruster working conditions and the cathode *** this paper,a laboratory 100 W class magnetically shielded Hall thruster was coupled with a hollow *** imaging and electrostatic probe were employed to monitor and scan the plasma *** characteristics in the coupling region in non-self-sustained mode and self-sustained mode were *** of the coupling plume with the cathode position was *** show that,when turning the thruster into self-sustained mode or moving the cathode further away axially,the discharge current can be reduced by 6.4–10.6%restraining the electron current and improving *** particular,when the cathode is moved further,the electron conduction near the channel walls is *** electron current is reduced by 27.4%and the ion beam current is increased by 7%.Overall,this work shows that the working mode of the thruster and the position of the cathode greatly affect the coupling plasma *** play an important role in improving the utilizations of propellant and current.

关键词： Coupling region Electron conduction Hall thruster Hollow cathode Utilizations of propellant and current

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莽山土壤发生学属性的垂直分异与系统分类

土壤通报 2024年第2期55卷 301-309页

作者：田宇盛浩肖华翠欧阳宁相尹泽润邓泽澍张亮湖南农业大学资源学院湖南长沙410128 广电计量检测(湖南)有限公司湖南长沙410205 湖南财政经济学院湖南长沙410205

[目的]弄清亚热带地区花岗岩中山土壤发生学属性与土壤类型的垂直地带性分布规律。[方法]选取莽山不同海拔带的8个典型单个土体,野外观测土壤剖面形态,室内测定土壤理化性质,划分土壤类型,在地理发生分类、中国土壤系统分类和国际土壤... 详细信息

[目的]弄清亚热带地区花岗岩中山土壤发生学属性与土壤类型的垂直地带性分布规律。[方法]选取莽山不同海拔带的8个典型单个土体,野外观测土壤剖面形态,室内测定土壤理化性质,划分土壤类型,在地理发生分类、中国土壤系统分类和国际土壤系统分类之间进行参比。[结果]土体厚度介于18~180 cm,以山体中部最为浅薄。质地主要为砂质壤土和砂质黏壤土,黏粒含量随海拔升高而降低;山体上部(>1000 m)土壤B层有腐殖质、黏粒胶膜和黏粒累积形成的黏化层。土壤有机碳和CEC值随海拔升高而升高,但腐殖质层浅薄,多为淡薄表层。这些土壤指标呈垂直地带性,反映了花岗岩中山土壤发生学特性。供试剖面土壤呈酸性,铝饱和度和铁游离度较高,铁质特性与铝质现象普遍,CEC为9.7~29.1 cmol(+)kg^(-1),一些土壤发生学属性指标(土壤色调、pH、铁游离度、铝饱和度)无明显垂直地带性。中国土壤系统分类划分出富铁土、淋溶土、雏形土和新成土4个土纲、5个亚纲、6个土类、8个亚类、8个土族和8个土系。[结论]土纲垂直带谱为雏形土、富铁土(400~700 m)—雏形土、新成土(700~1200 m)—雏形土、淋溶土(1200~1800 m),呈组合、跨带地域分布规律。与土壤地理发生分类相比,土壤系统分类侧重体现更多土壤发生学属性指标,同一海拔带内划分出了更多土壤类型,反映土壤多样性。

关键词：花岗岩垂直带性成土因素土壤系统分类分类参比

校企联合构建混合式人工智能课程实践教学体系的应用研究

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梧州学院学报 2024年第4期34卷 69-76页

作者：林乐平欧阳宁王土央桂林电子科技大学信息与通信学院广西桂林541004

当前人工智能技术和产业飞速发展,加快人工智能工程人才培养,提升人工智能信息素养,强化人工智能工程能力是学校人才培养的重点。针对电子信息工程专业人工智能课程,以教育部—华为“智能基座”产教融合协同育人基地项目为依托,基于华为... 详细信息

当前人工智能技术和产业飞速发展,加快人工智能工程人才培养,提升人工智能信息素养,强化人工智能工程能力是学校人才培养的重点。针对电子信息工程专业人工智能课程,以教育部—华为“智能基座”产教融合协同育人基地项目为依托,基于华为ModelArts、HiLens、Atlas的“端云协同”实践平台,构建了集线上原理学习、线上模拟测试、线下物理实验、应用场景方案设计和多维度课程评价为一体的线上线下融合实践教学体系,完现了人脸识别、口罩识别、花卉识别、手写体识别等人机协同教育的实验项目。应用研究结果表明:构建的“一云一端”“一软一硬”、面向不同应用场景的人工智能课程实验教学平台,对加快人工智能工程人才培养、提升人工智能信息素养、强化人工智能工程能力的人才培养起到重大推动作用,将为生成式人工智能在教育领域中的应用提供优秀案例。

关键词：人工智能课程实践教学校企联合线上线下融合端云协同

Flow Pattern and Heat Transfer Behavior of Boiling Two-Phase Flow in Inclined Pipes

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Journal of Thermal Science 1992年第3期1卷 196-202页

作者： Liu Dezhang ouyang ning Nanjing Aeronautical Institute, 210016 Nanjing, China Nanjing Aeronautical Institute Nanjing China

Movable Electrical Conducting Probe (MECP), a kind of simple and reliable measuring transducer, used for predicting full-flow-path flow pattern in a boiling vapor/liquid two-phase flow is introduced in this paper. When the test pipe is set at different inclination angles, several kinds of flow patterns, such as bubble, slug, churn, intermittent, and annular flows, may be observed in accordance with the locations of MECP. By means of flow pattern analysis, flow field numerical calculations have been carried out, and heat transfer coefficient correlations along full-flow-path derived. The results show that heat transfer performance of boiling two-phase flow could be significantly augmented as expected in some flow pattern zones. The results of the investigation, measuring techniques and conclusions contained in this paper would be a useful reference in foundational research for prediction of flow pattern and heat transfer behavior in boiling two-phase flow, as well as for turbine vane liquid-cooling design.

关键词： liquid/vapor two phase flow inclined pipes flow patterns heat transfer coefficient.

秸秆还田与耕作方式对双季稻土壤团聚体及碳氮含量的影响

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浙江农业学报 2024年第6期36卷 1347-1356页

作者：熊瑞欧阳宁欧茜钟康裕周文涛王泓睿龙攀徐莹傅志强湖南农业大学农学院湖南长沙410128 作物生理与分子生物学教育部重点实验室湖南长沙410128

为探讨南方双季稻区秸秆还田与不同耕作方式结合对土壤团聚体组成及土壤有机碳、全氮含量的影响,在湖南双季稻区开展了主区为秸秆还田(S1)与不还田(S0),副区为免耕(NT)、浅旋耕(RT)、深耕(TT)的大田裂区试验。结果表明,与其他处理相比,S... 详细信息

为探讨南方双季稻区秸秆还田与不同耕作方式结合对土壤团聚体组成及土壤有机碳、全氮含量的影响,在湖南双季稻区开展了主区为秸秆还田(S1)与不还田(S0),副区为免耕(NT)、浅旋耕(RT)、深耕(TT)的大田裂区试验。结果表明,与其他处理相比,S1+TT处理下0~10 cm土层早、晚稻的土壤大团聚体质量分数分别显著(P<0.05)提高1.70%~9.03%、4.48%~30.53%;10~20 cm土层土壤团聚体的平均质量直径和几何平均直径显著高于除S0+TT外的其他处理,在早稻上二者分别提高了7.23%~18.67%和4.35%~10.77%,在晚稻上二者分别提高了5.06%~23.88%和4.94%~23.19%;早稻10~20 cm土层(除S1+NT处理外)、晚稻0~10 cm土层的全氮含量分别显著提高13.04%~23.81%、10.14%~40.74%;早、晚稻10~20 cm土层和早稻0~10 cm土层的土壤有机碳含量分别显著提高4.36%~26.70%、3.83%~21.71%、3.86%~10.92%。综上,在双季稻区秸秆还田搭配深耕可以提高土壤团聚体的稳定性,及土壤有机碳、全氮含量,有利于促进土壤耕作层团聚体结构稳定,提高土壤质量。

关键词：双季稻秸秆还田耕作方式团聚体稳定性

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湖南省水稻土有机碳剖面分布特征及影响因素

土壤通报 2024年第1期55卷 84-92页

作者：沈璇玚段良霞欧阳宁相盛浩袁红张亮张扬珠周清谢红霞湖南农业大学资源环境学院湖南长沙410000 湖南财政经济学院工程管理学院湖南长沙410000

【目的】按土壤剖面发生层分析水稻土有机碳剖面分布特征及其影响因素。【方法】通过测定湖南省58个水稻土剖面各发生层土壤有机碳含量,分析水稻土剖面有机碳分布特征,并利用地理探测器解析水稻土有机碳含量空间分异的影响因素。【结果... 详细信息

【目的】按土壤剖面发生层分析水稻土有机碳剖面分布特征及其影响因素。【方法】通过测定湖南省58个水稻土剖面各发生层土壤有机碳含量,分析水稻土剖面有机碳分布特征,并利用地理探测器解析水稻土有机碳含量空间分异的影响因素。【结果】①湖南省水稻土剖面土壤有机碳平均含量为9.30 g kg^(−1),其在发生层上的分布表现为耕作层(22.94 g kg^(−1))>犁底层(15.09 g kg^(−1))>底土层(6.93 g kg^(−1))。②不同成土母质发育的土壤中,石灰岩风化物发育的水稻土发生层有机碳含量最大;不同质地的土壤中,水稻土各类发生层有机碳含量整体上表现为随粉粒含量的增加而增大。③各发生层有机碳空间分布均呈现西南高,东北低的格局。④地理探测器结果显示,容重对各发生层水稻土有机碳含量空间分异解释程度最高,且与其他因子交互之后解释力显著增强。【结论】湖南省水稻土有机碳含量在不同剖面发生层存在显著性差异,其空间分布是由多因子交互作用形成的,容重对各发生层有机碳解释力最高。

关键词：土壤有机碳发生层成土母质质地地理探测器

Increasing Fatty Acids in Rice Root Improves Silence of Rice Seedling to Salt Stress

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Rice science 2019年第6期26卷 339-342页

作者： LIU Ling CHEN Jin TAN Yanning ZHOU Tianshun ouyang ning ZENG Jia YUAN Dingyang DUAN Meijuan Long Ping Branch Graduate School of Hunan University College of Bioscience and Biotechnology Hunan Agricultural University Hunan Academy of Agricultural Sciences State Key Laboratory of Hybrid Rice Hunan Hybrid Rice Research Center College of Agronomic Hunan Agricultural University

Salt stress is one of the major abiotic stresses around the world, and salt salinity is one of the major constrains affecting rice production (Tu et al, 2014;Reddy et al, 2017). According to the statistics, more than one billion hectares of the land in the major continents are affected by salinity (Fageria et al, 2012;Zhou et al, 2018). Rice is a salt sensitive crop, considered more sensitive to salt stress during early stage (Hasanuzzaman et al, 2009). Understanding the method to improve plant salt tolerance is a potential way to enhance agriculture productivity in the future (Jing and Zhang, 2017). Polyunsaturated fatty acid (PUFA) on plasma membrane plays important roles in salt tolerance through enhancing the activity of Na^+/H^+ transporters (López-Pérez et al, 2009).

关键词： Fatty Acids in Rice Root Rice Seedling Salt

萍乡市育龄妇女脊髓性肌萎缩症SMN1基因突变发生率及分布特征

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中国妇幼保健 2024年第11期39卷 2075-2078页

作者：欧阳宁钟丽群李彦琳陈海萍何蓉刘红宇萍乡市妇幼保健院医学遗传科江西萍乡337000 萍乡市妇幼保健院孕期保健科萍乡市妇幼保健院妇科萍乡市妇幼保健院遗传实验室

目的评估萍乡市育龄妇女脊髓性肌萎缩症(SMA)运动神经元存活基因1(SMN1)突变发生率及分布特征。方法选取2022年1月—2023年5月在萍乡市进行产前检查的1741例孕妇及46名配偶作为研究对象,使用聚合酶链式反应(PCR)-熔解曲线法检测SMN1基... 详细信息

目的评估萍乡市育龄妇女脊髓性肌萎缩症(SMA)运动神经元存活基因1(SMN1)突变发生率及分布特征。方法选取2022年1月—2023年5月在萍乡市进行产前检查的1741例孕妇及46名配偶作为研究对象,使用聚合酶链式反应(PCR)-熔解曲线法检测SMN1基因外显子7(E7)和外显子8(E8)的拷贝数。结果1741例孕妇中,SMN1基因异常46例(2.64%,1∶37),其中E7单独杂合缺失3例(0.17%,1∶580),E8单独杂合缺失9例(0.52%,1∶193),E7和E8同时杂合缺失34例(1.95%,1∶51),对上述孕妇均进行复检,阳性筛查率仍为100.00%。46名配偶被召回检测,其中2对夫妇均存在E7杂合缺失,2例孕妇均接受产前胎儿SMA诊断,1例胎儿正常(继续妊娠),1例SMA患儿(E7和E8纯合缺失,终止妊娠),其余胎儿均继续妊娠。结论积极筛查萍乡市育龄妇女SMN1基因异常的发生率及分布特征,联合对高危胎儿进行产前诊断,可有效避免SMA患儿的出生。

关键词：育龄妇女脊髓性肌萎缩症运动神经元存活基因1 产前诊断萍乡市

Fabrication of micro spherulitic particles of carbamazepine-hesperetin cocrystal via QESD with enhanced manufacturability and dissolution

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Particuology 2024年第10期93卷 11-21页

作者： Jinbo ouyang Lishan Liu Zichen ning Zhuoshan Gong Limin Zhou Feiqiang He Zhi Gao Li Xu Shichao Du Huaiyu Yang Jiangxi Province Key Laboratory of Functional Organic Polymers East China University of TechnologyNanchang330013China School of Pharmaceutical Science Qilu University of TechnologyJinan250353China Department of Chemical Engineering Loughborough UniversityLeicestershireLE113TUUK

Granulation is an effective method for improving the flowability of drugs, particularly when they are in needle form. Carbamazepine-hesperetin (CBZ-HPE) cocrystal is a needle-like crystal with low solubility and poor flowability, which limits its application. To address this issue, this study aimed to obtain CBZ-HPE microspheres using the quasi-emulsion solvent diffusion (QESD) technique. The preparation process was monitored using polarized light microscopy, and the formation mechanism was elucidated using the radial distribution function (RDF). The microspheres were extensively characterized using PXRD, DSC, TGA, and SEM. Furthermore, the effects of surfactants, contents, and rotational speeds on the morphology and particle size distribution of microspheres were analyzed to determine the optimal experimental conditions. Based on these findings, naringenin and quercetin, the active ingredients of traditional Chinese medicine, were chosen to successfully prepare CBZ-HPE multicomponent microspheres. This research provides a foundation for increasing drug powder properties and drug conjugation through the preparation of microspheres.

关键词： Carbamazepine-hesperetin cocrystal Quasi-emulsion solventdiffusion(QESD) technique Microspheres Flowability Dissolution rate