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Response of yield,quality,water and nitrogen use efficiency of tomato to different levels of water and nitrogen under drip irrigation in Northwestern China

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Journal of Integrative Agriculture 2017年第5期16卷 1153-1161页

作者： DU Ya-dan cao Hong-xia LIU Shi-quan GU Xiao-bo cao Yu-xin Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Area Ministry of Education/Northwest A&F UniversityYangling 712100P.R.China

The objective of this study was to investigate the effects of applying different amounts of water and nitrogen on yield, fruit quality, water use efficiency （WUE）, irrigation water use efficiency （IWUE） and nitrogen use efficiency （NUE） of drip-irrigated greenhouse tomatoes in northwestern China. The plants were irrigated every seven days at various proportions of 20-cm pan evaporation （Ep）. The experiment consisted of three irrigation levels （11, 50% Ep; 12, 75% Ep; and 13, 100% Ep） and three N application levels （N1, 150 kg N ha^-1; N2, 250 kg N ha^-1;and N3, 350 kg N ha^-1）. Tomato yield increased with the amount of applied irrigation water in 12 and then decreased in 13. WUE and IWUE were the highest in Ii. WUE was 16.5% lower in 12 than that in I1, but yield was 26.6% higher in 12 than that in I1. Tomato yield, WUE, and IWUE were significantly higher in N2 than that in N1 and N3. NUIE decreased with increasing N levels but NUE increased with increase the amount of water applied. Increasing both water and N levels increased the foliar net photosynthetic rate. I1 and 12 treatments significantly increased the contents of total soluble solids （TSS）, vitamin C （VC）, lycopene, soluble sugars （SS）, and organic acids （OA） and the sugar：acid ratio in the fruit and decreased the nitrate content. TSS, VC, lycopene, and SS contents were the highest in N2. The harvest index （HI） was the highest in 12N2. 12N2 provided the optimal combination of tomato yield, fruit quality, and WUE. The irrigation and fertilisation regime of 75% Ep and 250 kg N ha^-1 was the best strategy of water and N management for the production of drip-irrigated greenhouse tomato.

关键词： tomato drip irrigation yield fruit quality water use efficiency (WUE)

Mechanisms,monitoring and modeling of shrub encroachment into grassland:a review

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International Journal of Digital Earth 2019年第6期12卷 625-641页

作者： xin cao Yu Liu Xihong Cui Jin Chen Xuehong Chen State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijingPeople’s Republic of China Beijing Engineering Research Center for Global Land Remote Sensing Products Institute of Remote Sensing Science and EngineeringFaculty of Geographical ScienceBeijing Normal UniversityBeijingPeople’s Republic of China

Shrub encroachment into arid and semi-arid grasslands has elicited extensive research attention worldwide under the background of climate change and increasing anthropogenic *** encroachment may considerably impact local ecosystems and economies,including the conversion of the structure and function of ecosystems,the shift in ambient conditions,and the weakness of local stock farming *** article reviews recent research progresses on the shrub encroachment process and mechanism,shrub identification and dynamic monitoring using remote sensing,and modeling and simulation of the shrub encroachment process and *** studies can help to evaluate the ecological effect of shrub encroachment,and thus,practically manage and recover the ecological environment of degraded ***,the lack of effective measures and data for monitoring shrub encroachment at a large spatial scale severely limits research on the mechanism,modeling,and simulation of shrub encroachment,and the shrub encroachment stages can hardly be quantitatively defined,resulting in insufficient analysis and simulation of shrub encroachment for different spatiotemporal scales and stages *** in remote sensingbased shrub encroachment dynamic monitoring might be crucial for analyzing and understanding the process and mechanism of shrub encroachment,and multi-disciplinary and multi-partnerships are required in the shrub encroachment studies.

关键词： Shrub encroachment arid and semi-arid grassland mechanism dynamic monitoring modeling and simulation

Magnetic properties of oxides and silicon single crystals

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Chinese Physics B 2022年第8期31卷 141-148页

作者： Zhong-Xue Huang Rui Wang xin Yang Hao-Feng Chen Li-xin cao Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The magnetic properties of single crystals Si,Sr Ti O_(3),La Al O_(3),Mg O,and(La,Sr)(Al,Ta)O_(3)were investigated *** origins of the magnetizations of these crystals,namely,an intrinsic diamagnetic,a paramagnetic,and a ferromagnetic contribution,have been found to influence the magnetic signals measured on the crystals,in some important application scenarios such crystals being served as substrates with the magnetic thin film epitaxially grown *** analyses methodologies were developed and thorough investigations were performed on the crystals with the intrinsic materials parameters thus revealed,especially that the intrinsic diamagnetic susceptibility differential dχdia/d T were identified quantitatively for the first time in Sr Ti O_(3),La Al O_(3),Mg O,and(La,Sr)(Al,Ta)O_(3).The paramagnetic contribution is found to be the key in terms of the magnetic properties of the crystals,which in turn is in fact a consequence of the 3d impurities doping inside the *** the intrinsic materials parameters are given in this paper as datasets,the datasets are openly available at https://***/10.57760/sciencedb.j00113.00028.

关键词： magnetism single crystals oxides silicon

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自贡有人机与无人机双跑道运行安全风险分析

中国民航飞行学院学报 2024年第4期35卷 15-18,23页

作者：刘亮亮张柯张敬坤曹鹏飞曹鑫中国民用航空飞行学院四川广汉618307 自贡凤鸣通用机场四川自贡643020

通过研究自贡凤鸣通用机场现状、飞行人员跑道识别能力、空管保障能力,分析可能存在的风险和隐患,以人防、技防、物防等手段,从管理、技术、设施设备入手,完善双跑道联防联控机制,达到双跑道安全运行标准。本研究发现,通用航空作为航空... 详细信息

通过研究自贡凤鸣通用机场现状、飞行人员跑道识别能力、空管保障能力,分析可能存在的风险和隐患,以人防、技防、物防等手段,从管理、技术、设施设备入手,完善双跑道联防联控机制,达到双跑道安全运行标准。本研究发现,通用航空作为航空领域的重要分支,无人机产业发展迅速,有人机跑道加无人机专用跑道的双跑道运行可能成为将来通用航空机场和支线机场标配,必须对其空管标准、运行流程和进离港程序等进行全方位梳理、再造和优化,引入更先进和高效的管理方法和技术来保障运行安全。

关键词：自贡通用机场双跑道无人机跑道安全

考虑韧性提升的输电网灾前预防检修多目标多阶段优化

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电测与仪表 2024年第2期61卷 130-137页

作者：梁海平石皓岩王铁强鲁鹏曹欣杨晓东华北电力大学(保定) 河北保定071003 国网河北省电力有限公司石家庄050021

极端气象灾害易使输电网发生大面积故障。输电网设备的健康程度影响着输电网抵御极端气象灾害物理层面的能力。为进一步提升输电网抗灾能力,减轻经济损失,从输电网韧性提升的角度出发,对输电网灾前预防检修策略进行研究。首先提出将灾... 详细信息

极端气象灾害易使输电网发生大面积故障。输电网设备的健康程度影响着输电网抵御极端气象灾害物理层面的能力。为进一步提升输电网抗灾能力,减轻经济损失,从输电网韧性提升的角度出发,对输电网灾前预防检修策略进行研究。首先提出将灾害风险抵御力作为输电网灾时韧性评价指标,同时针对极端灾害的时空特性,采用场景分析法来计算韧性指标。根据输电网灾前预防检修的韧性提升、检修风险、经济性的要求,提出输电网灾前预防检修多目标多阶段优化模型,并采用NSGA-II算法与数学规划求解器结合的方法求解。采用IEEE RTS-79算例对优化模型的有效性进行了仿真验证。算例结果表明,文章所提优化模型能得出Pareto前沿以及最优折衷解,并以此得到最优灾前预防检修计划,在提升灾时韧性的同时控制灾前预防检修的风险与费用,从而帮助电网运行人员做出科学决策,具有较好的应用价值。

关键词：输电网韧性输电网灾前预防检修输电网韧性评估多目标优化

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膨胀型钢结构防火涂料的研究进展

涂料工业 2024年第3期54卷 59-65页

作者：吴沛沛张依晴田爱琴曹鑫张玲王锦张冬海中车青岛四方机车车辆股份有限公司国家工程研究中心山东青岛266111 北京科技大学化学与生物工程学院化学与化学工程系北京100083 中国科学院过程工程研究所多相复杂系统国家重点实验室北京100190 上海鹏图抗菌新材料有限公司上海201800

以P-C-N(聚磷酸铵APP、季戊四醇PER、三聚氰胺MEL组成)为膨胀体系的钢结构防火涂料应用广泛,但普遍存在耐水性差、防火抑烟效果达不到预期等问题。以P-C-N膨胀体系的优化及发展为主线,梳理和总结了膨胀型钢结构防火涂料相关研究。发现... 详细信息

以P-C-N(聚磷酸铵APP、季戊四醇PER、三聚氰胺MEL组成)为膨胀体系的钢结构防火涂料应用广泛,但普遍存在耐水性差、防火抑烟效果达不到预期等问题。以P-C-N膨胀体系的优化及发展为主线,梳理和总结了膨胀型钢结构防火涂料相关研究。发现通过对膨胀体系中亲水性组分的改性来优化P-C-N膨胀体系、在防火涂料中添加碳材料、过渡金属化合物等填料,可协同提高防火涂料性能并取得了较好的效果。然而,这些研究仍未能很好地解决防火涂料环境耐久性及高效防火的发展要求,因此开发新的膨胀体系已成为当前研究的需求与热点。

关键词：钢结构防火涂料膨胀体系研究进展

基于PSO-RF模型的汉江流域参考作物蒸散量模拟研究

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中国农业气象 2024年第8期45卷 849-859页

作者：葛杰曹绮欣张晓鹏雷龙陈至立冯家豪中国电建集团西北勘测设计研究院有限公司西安710065 河北天和咨询有限公司石家庄050000

选取1960−2017年汉江流域及附近24个气象站的逐日气象数据,构建16种基于粒子群算法优化随机森林(PSO-RF)的日尺度ET0计算模型,并与Hargreaves-Samani、Makkink和Irmark-Allen共3种模型进行比较,评价PSO-RF模型在汉江流域的适用性及可移... 详细信息

选取1960−2017年汉江流域及附近24个气象站的逐日气象数据,构建16种基于粒子群算法优化随机森林(PSO-RF)的日尺度ET0计算模型,并与Hargreaves-Samani、Makkink和Irmark-Allen共3种模型进行比较,评价PSO-RF模型在汉江流域的适用性及可移植性。结果表明:(1)PSO-RF模型能很好地识别各输入参数与日尺度ET0的非线性关系;仅采用最高气温(Tmax)、最低气温(Tmin)和地球外辐射(Ra)建立的PSO-RF2模型具有足够精度,平均MAE为0.402mm·d^(−1),RMSE为0.575mm·d^(−1),R^(2)为0.863;随输入气象要素数量增加,模型计算精度不断升高,平均MAE减小了37.9%,RMSE减小了36.3%,R^(2)升高了6.78%。(2)PSO-RF模型的计算精度优于相同输入参数的Hargreaves-Samani、Makkink和Irmark-Allen模型,平均MAE减小了43.6%、RMSE减小了34.5%,R2升高了4.12%。(3)PSO-RF模型在汉江流域具有较强的泛化能力和可移植性,分区建立的PSO-RF模型相互移植时,平均MAE为0.159mm·d^(−1),RMSE为0.245mm·d^(−1),R^(2)为0.974。因此缺乏气象数据时,基于PSO-RF建立的日尺度ET0计算模型可作为汉江流域日尺度ET0计算的推荐模型。

关键词：汉江流域参考作物蒸散量 PSO RF 可移植性

直线旋转开关磁阻电机的轴向速度控制与快速轴向定位

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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第3期41卷 300-310页

作者：孟徐颖曹鑫石瑞杰何洲辉邓旭邓智泉南京航空航天大学自动化学院南京210016 纽卡斯尔大学工程学院英国纽卡斯尔泰恩河畔NE17RU

目前直线旋转开关磁阻电机(Linear-rotary switched reluctance motor,LRSRM)只可实现轴向定位控制,两自由度运动方式较为单一。为提高LRSRM轴向控制性能,本文提出了一种轴向速度控制方法,通过线性位置/速度观测器协调控制转子的轴向位... 详细信息

目前直线旋转开关磁阻电机(Linear-rotary switched reluctance motor,LRSRM)只可实现轴向定位控制,两自由度运动方式较为单一。为提高LRSRM轴向控制性能,本文提出了一种轴向速度控制方法,通过线性位置/速度观测器协调控制转子的轴向位移和轴向速度,由转矩与轴向力的数学模型解算出转矩及轴向力绕组的给定电流,再将其分配到对应的绕组导通区间,分别进行电流滞环控制。该方法可以有效调节转子在旋转过程中的轴向定位速度。仿真和实验验证了所提方法的控制效果。

关键词：多自由度电机直线旋转开关磁阻电机轴向速度控制快速轴向定位

Dysfunction of synaptic endocytic trafficking in Parkinson's disease

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Neural Regeneration Research 2024年第12期19卷 2649-2660页

作者： xin Yi Ng Mian cao Programme in Neuroscience and Behavioural Disorders Duke-NUS Medical SchoolSingaporeSingapore Department of Physiology National University of SingaporeSingaporeSingapore

Parkinson's disease is characterized by the selective degeneration of dopamine neurons in the nigrostriatal pathway and dopamine deficiency in the *** precise reasons behind the specific degeneration of these dopamine neurons remain largely *** investigations have identified over 20 causative PARK genes and 90 genomic risk loci associated with both familial and sporadic Parkinson's ***,several of these genes are linked to the synaptic vesicle recycling process,particularly the clathrinmediated endocytosis *** suggests that impaired synaptic vesicle recycling might represent an early feature of Parkinson's disease,followed by axonal degeneration and the eventual loss of dopamine cell bodies in the midbrain via a"dying back"***,several new animal and cellular models with Parkinson's disease-linked mutations affecting the endocytic pathway have been created and extensively *** models faithfully recapitulate certain Parkinson's disease-like features at the animal,circuit,and cellular levels,and exhibit defects in synaptic membrane trafficking,further supporting the findings from human genetics and clinical *** this review,we will first summarize the cellular and molecular findings from the models of two Parkinson's disease-linked clathrin uncoating proteins:auxilin(DNAJC6/PARK19)and synaptojanin 1(SYNJ1/PARK20).The mouse models carrying these two PARK gene mutations phenocopy each other with specific dopamine terminal pathology and display a potent synergistic ***,we will delve into the involvement of several clathrin-mediated endocytosis-related proteins(GAK,endophilin A1,SAC2/INPP5 F,synaptotagmin-11),identified as Parkinson's disease risk factors through genome-wide association studies,in Parkinson's disease *** will also explore the direct or indirect roles of some common Parkinson's disease-linked proteins(alpha-synuclein(PARK1/4),Parkin(PARK2),and LRRK2(PARK

关键词： autophagy auxilin/PARK19 clathrin-mediated endocytosis dopamine neurons neurodegeneration nigrostriatal pathway Parkinson's disease synaptic vesicle recycling synaptojanin1/PARK20