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Characteristics of runoff processes and nitrogen loss via surface flow and interflow from weathered granite slopes of Southeast China

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Journal of Mountain Science 2019年第5期16卷 1048-1064页

作者： deng Long-zhou FEI kai SUN Tian-yu ZHANG Li-ping FAN Xiao-juan NI Liang College of Environmental and Resource Sciences Zhejiang University Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment Agricultural Experiment Station Zhejiang University

Rainfall intensity and slope gradient are two of the most important factors affecting the variations of runoff nitrogen(N).However,the effects of slope gradient and rainfall intensity on N loss via surface flow and interflow on weathered granite slopes are poorly *** this study,12 artificial rainfalls(three rainfall intensities and four slope gradients)were simulated to investigate the coupling loss characteristics of surface flow–interflow–total nitrogen(TN),nitrate nitrogen(NO_3^--N)and ammonia nitrogen(NH_4^+-N)on weathered granite *** results show that slope gradient has a greater impact on the surface flow when the rainfall intensity is relatively *** effect gradually weakens with the decrement of rainfall *** interflow yield increases firstly with the prolongation of rainfall duration,then tends to be stable and finally *** total surface flow percentage increases with rainfall intensity while it decreases with increasing slope gradient with a range of 10.88%-71.47%.The TN loss concentration of the surface flow continually decreases with rainfall duration while that of the interflow shows different ***,the TN loss loads of both surface flow and interflow increase with increasing rainfall intensity and slope *** NO_3^--N concentration of interflow is much higher than that of the surface *** NH_4^+-N concentration is always less than that of NO_3^--N with no significant difference between surface flow and *** percentages of the TN,NO_3^--N,and NH_4^+-N total loss load and concentration of surface flow and interflow were *** results show that N loss via both surface flow and interflow occurs mainly in the form of NO_3^--*** of the N loss is caused by interflow which is the preferential path of runoff nutrient *** findings provide data support and underlying insights for the control of runoff and N loss on the weathered granite slopes.

关键词： Simulated rainfall Nitrogen loss Surface flow Interflow Slope gradient Rainfall intensity Weathered granite slope

Rapidly modifying microstructure and mechanical properties of AA7150 Al alloy processed with electropulsing treatment

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Journal of Materials Science & Technology 2021年第36期95卷 172-179页

作者： kai Chen Lihua Zhan Wenfang yu College of Mechanical and Electrical Engineering of Central South University Changsha 410083China State Key Laboratory of High-Performance Complex Manufacturing Central South UniversityChangsha 410083China Light Alloy Research Institute of Central South University Changsha 410083China

Studies show that the proper solid solution treatment(SST)is a key step in the precipitation strengthening of AA7150 Al *** the superior characteristics of the fully dissolved phase,it has major drawbacks,including high consumption of energy and low ***,electropulsing treatment(EPT)has been proposed to study dissolved precipitations and modify microstructures of AA7150 Al alloy faster than conventional *** have been conducted in the present article,and the obtained results show that EPT can promote the rapid dissolution of theη’phase at relatively low temperatures in only 20 ***,the strength and ductility of electropulsed samples decrease *** with conventional SST,EPT accelerates recrystallization and obtains relatively fine grains after 20 and 50 s electric ***,as the EPT time increases,the corresponding non-uniform local heating and the electron force promote dislocation generation and annihilation.

关键词： AA7150 Al alloy Electropulsing treatment Rapid dissolution Recrystallization Dislocation

Design of a Bio-inspired,Two-winged,Flapping-wing Micro Air Vehicle with High-lift Performance

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Journal of Bionic Engineering 2024年第3期21卷 1191-1207页

作者： kai Hu Huichao deng Shengjie Xiao Gongyu Yang yuhong Sun Space Robot Laboratory The School of Mechanical EngineeringBeihang UniversityBeijing100191China

In this paper,we present the development of our latest flapping-wing micro air vehicle(FW-MAV),named Explobird,which features two wings with a wingspan of 195 mm and weighs a mere 25.2 g,enabling it to accomplish vertical take-off and hover *** devised a novel gear-based mechanism for the flapping system to achieve high lift capability and reliability and conducted extensive testing and analysis on the wings to optimise power matching and lift *** Explobird can deliver a peak lift-to-weight ratio of 1.472 and an endurance time of 259 s during hover flight powered by a single-cell LiPo *** the inherent instability of the prototype,we discuss the derivatives of its longitudinal system,underscoring the importance of feedback control,position of the centre of gravity,and increased *** demonstrate the effect of damping enhancement on stability,we also designed a passive stable ***,the vehicle is actively stabilised in roll by adjusting the wing root bars and in pitch through high-authority tail control,whereas yaw is passively *** a series of flight tests,we successfully demonstrate that our prototype can perform vertical take-off and hover flight under wireless *** promising results position the Explobird as a robust vehicle with high lift capability,paving the way towards the use of FW-MAVs for carrying load equipment in multiple tasks.

关键词： Flapping wing Biologically inspired robots Mechanical design Flight dynamics Damping enhancement

淫羊藿苷预处理增强人牙周膜干细胞对M1型巨噬细胞的影响

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中国组织工程研究 2025年第7期29卷 1328-1335页

作者：喻婷吕冬梅邓浩孙涛程钎西南医科大学口颌面修复重建和再生泸州市重点实验室四川省泸州市646000 西南医科大学口腔医学研究所四川省泸州市646000 西南医科大学附属口腔医院正畸科四川省泸州市646000 西南医科大学口腔医学院四川省泸州市646000

背景:人牙周膜干细胞对M1型巨噬细胞促炎功能有一定抑制作用,具有抗炎等药理活性的淫羊藿苷是否能增强人牙周膜干细胞对M1型巨噬细胞的抑制作用尚不明确。目的:探究淫羊藿苷预处理人牙周膜干细胞后对M1型巨噬细胞的影响。方法:分离培养... 详细信息

背景:人牙周膜干细胞对M1型巨噬细胞促炎功能有一定抑制作用,具有抗炎等药理活性的淫羊藿苷是否能增强人牙周膜干细胞对M1型巨噬细胞的抑制作用尚不明确。目的:探究淫羊藿苷预处理人牙周膜干细胞后对M1型巨噬细胞的影响。方法:分离培养原代人牙周膜干细胞,并进行鉴定。对THP-1细胞进行诱导,采用免疫荧光染色及PCR进行M1型巨噬细胞鉴定。用含浓度10^(-7),10^(-6),10^(-5),10^(-4)mol/L淫羊藿苷的α-MEM完全培养基培养人牙周膜干细胞1,3,5,7 d,采用CCK-8法筛选合适的淫羊藿苷浓度进行实验。将α-MEM完全培养基、未处理的人牙周膜干细胞α-MEM条件培养基及淫羊藿苷预处理24 h的人牙周膜干细胞α-MEM条件培养基与RPMI-1640完全培养基以1∶1的比例对M1型巨噬细胞进行条件培养,分别为对照组、未处理组及预处理组,24 h后RT-PCR法检测M1型巨噬细胞炎症因子的mRNA表达情况;ELISA法检测M1型巨噬细胞炎症因子的蛋白表达情况;Western blot检测M1/M2型巨噬细胞表面标记物及核转录因子κB通路相关蛋白的表达。结果与结论:(1)CCK-8检测结果显示,10^(-7),10^(-6),10^(-5),10^(-4)mol/L淫羊藿苷对人牙周膜干细胞均无细胞毒性,且从第5天起,各浓度都提高了细胞活力,促进细胞增殖,选择10^(-4)mol/L淫羊藿苷进行后续实验。(2)RT-PCR法及ELISA检测结果显示,与对照组相比,未处理组及预处理组均降低了M1型巨噬细胞白细胞介素1β、白细胞介素6及肿瘤坏死因子α的表达与分泌(P<0.05),且预处理组低于未处理组(P<0.05)。(3)Western blot检测结果显示,与未处理组相比,预处理组CD86的表达明显降低(P<0.05);与对照组相比,未处理组和预处理组M2型巨噬细胞表面标志物CD206的表达均升高(P<0.01),且预处理组明显高于未处理组(P<0.01);M1型巨噬细胞经24 h条件培养后,与对照组相比,核转录因子κB/P65的表达在未处理组和预处理组均有降低(P<0.01),p-IκBα的表达仅在预处理组降低(P<0.01);与未处理组相比,预处理组核转录因子κB/P65和p-IκBα的表达均显著降低(P<0.05),而IκBα在3组中的表达差异无显著性意义。(4)上述结果证实,淫羊藿苷增强了人牙周膜干细胞对M1型巨噬细胞的抑制作用,此作用可能与抑制了巨噬细胞的核转录因子κB信号通路相关。

关键词：人牙周膜干细胞淫羊藿苷巨噬细胞条件培养基共培养表面标志物炎症因子抗炎核转录因子κB信号通路

A Review of Research on the Mechanical Design of Hoverable Flapping Wing Micro-Air Vehicles

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Journal of Bionic Engineering 2021年第6期18卷 1235-1254页

作者： Shengjie Xiao kai Hu Binxiao Huang Huichao deng Xilun Ding Robotics Institute Beihang UniversityBeijing 100191China Beijing Advanced Innovation Center for Biomedical Engineer Beihang UniversityBeijing 100191China

Most insects and hummingbirds can generate lift during both upstroke and downstroke with a nearly horizontal flapping stroke plane,and perform precise hovering ***,most birds can utilize tails and muscles in wings to actively control the flight performance,while insects control their flight with muscles based on wing root along with wing’s passive *** on the above flight principles of birds and insects,Flapping Wing Micro Air Vehicles(FWMAVs)are classified as either bird-inspired or insect-inspired *** this review,the research achievements on mechanisms of insect-inspired,hoverable FWMAVs over the last ten years(2011-2020)are *** also provide the definition,function,research status and development prospect of hoverable *** discuss it from three aspects:bio-inspiration,motor-driving mechanisms and intelligent actuator-driving *** this,research groups involved in insect-inspired,hoverable FWMAV research and their major achievements are summarized and classified in ***,trends and challenges about the mechanism are compiled and ***,this paper presents conclusions about research on mechanical structure,and the future is discussed to enable further research interests.

关键词： Hoverable Flapping wing Insect-inspired Mechanical design Motor drive Intelligent actuator

Evolutionary Pattern and Effect of Administrative Division Adjustment During Urbanization of China:Empirical Analysis on Multiple Scales

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Chinese Geographical Science 2018年第5期28卷 758-772页

作者： yu Hu deng yu XU Shan Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Science Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of Science

The adjustment of administrative divisions is one of the important factors guiding China's urbanization, which has profound economic and social effects for regional development. In this paper, we comprehensively describe the process of the adjustment of administrative divisions at provincial and municipal levels in China and summarize the effects on the basic structure and patterns of the spatial development. We quantitatively assess the effects on fields such as urbanization and social economy through the use of multidimensional scaling. The results show that: 1) Upgrading county to municipality(or city-governed district) is the main way of adjusting the administrative divisions. It is also an important factor in the spatial differentiation of interprovincial urbanization. China's population urbanization can be divided into four patterns including interprovincial migration, provincial migration, natural growth, and growth caused by the adjustment of administrative divisions, which is also the main reason for the increased Chinese urbanization rate at the provincial level. 2) Taking the city of Beijing as an example, we generalize five adjustment patterns made to administrative divisions: the set-up of sub-districts, the set-up of regional offices, the upgrading of townships to sub-districts, the upgrading of townships to towns, and the set-up of towns and the addition of new regional offices. We summarize the municipal urban spatial structure, including the sub-district office area in the central urban area, the regional office area in the new urban area, the mixed area of villages, towns, and sub-district offices in the suburb area, and the township area in the outer suburb area. 3) The adjustment of administrative divisions triggers a significant circulative accumulation effect, resulting in the spatial locking of population and industrial agglomeration. It affects the evolution of the urban spatial form and plays an important role in shaping the urban spatial st

关键词： administrative division adjustment evolutionary structure effect evaluation multidimensional scaling urbanization China

Interfacial defective Ti^(3+) on Ti/TiO_(2) as visible-light responsive sites with promoted charge transfer and photocatalytic performance

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Journal of Materials Science & Technology 2022年第11期106卷 139-146页

作者： Yangfan Zhang Yao Li Han yu kai yu Hongbing yu College of Environmental Science and Engineering Nankai UniversityTianjin 300350China Department of Water Resources Engineering Lund University22100 LundSweden School of Economics and Management Tiangong UniversityTianjin 300350China

Defect sites on oxide semiconductors play a crucial role in promoting photocatalytiperformance and mod-ulating the bandgap structure of ***,the role of interfacial coordinatively unsatu-rated defect sites between metal and oxide in photocatalysis is still under ***,we designed an experiment to probe the role of interfacial coordinatively unsaturated defect *** this work,a se-ries of Ti/TiO_(2) photocatalysts with varying concentrations of interfacial Ti^(3+)sites were prepared through an epitaxial growth method under hydrothermal *** experimental and computational investigations,the roles of interfacial defect sites were discussed in *** the one hand,the inter-facial coordinatively unsaturated Ti^(3+)sites could act as visible-light-responsive sites in photocatalytic reactions due to the overlap and hybridization of multiple electronic *** the other hand,the Ti/TiO_(2) interface exhibited a certain degree of metallic character near the Fermi level because of the par-tial delocalization and redistribution of electrons,facilitating the charge migration and separation across the metal-oxide ***,the obtained Ti/TiO_(2) catalysts showed notably enhanced charge transfer efficiency and visible light photocatalytic activity compared to their pristine *** work may provide a new perspective to interfacial defect engineering in classic metal/oxide heterojunc-tion photocatalysts and figure a more precise direction to synthesize higher effective photocatalysts for environmental governance.

关键词： Interfacial defect engineering Ti/TiO_(2)interface Coordinatively unsaturated site Visible-light photocatalysis DFT calculation

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量子核判别分析算法

郑州大学学报（理学版） 2025年第1期57卷 61-66页

作者：康榕乘余凯张新林崧郭躬德福建师范大学计算机与网络空间安全学院福建福州350117 福建师范大学数字福建环境监测物联网实验室福建福州350117 福建师范大学数学与统计学院福建福州350117

核判别分析法通过核函数扩展了线性判别分析对非线性数据的处理能力,成为模式识别领域中一个重要的分支。然而,随着数据的指数增长,经典核判别分析算法在提取特征时会消耗大量计算资源。针对这一问题,利用量子叠加性和并行性提出了一种... 详细信息

核判别分析法通过核函数扩展了线性判别分析对非线性数据的处理能力,成为模式识别领域中一个重要的分支。然而,随着数据的指数增长,经典核判别分析算法在提取特征时会消耗大量计算资源。针对这一问题,利用量子叠加性和并行性提出了一种量子核判别分析算法。首先,借助量子随机存储器技术与控制旋转操作构造需要的类间矩阵和类内矩阵所对应的密度算子;然后,融入线性方程的求解思路并行获取特征态。理论分析表明,所提算法与经典算法相比具有指数级加速。

关键词：量子机器学习非线性判别分析核函数特征提取量子厄米特链积相位估计

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基线选择对热浪事件计算方法的影响

河南师范大学学报（自然科学版） 2025年第1期53卷 125-135页

作者：陈远范宏翔彭凯邓建明彭霁虹中国科学院南京地理与湖泊研究所南京210008 重庆亿森动力环境科技有限公司重庆400000

热浪已成为世界上危害性最大的自然灾害之一,近年来全球都经历了日益刷新纪录的热浪事件,然而学术界还没有统一热浪定义.基于对目前还存在争议的热浪基线选择(即参考气候背景)进行研究.通过统计1951-2022年我国692个气象站逐日平均气温... 详细信息

热浪已成为世界上危害性最大的自然灾害之一,近年来全球都经历了日益刷新纪录的热浪事件,然而学术界还没有统一热浪定义.基于对目前还存在争议的热浪基线选择(即参考气候背景)进行研究.通过统计1951-2022年我国692个气象站逐日平均气温数据,基于分位数法对比了固定基线、变化基线和滑动基线3种方法对于暴发频次、持续天数、最大强度和热浪间隔时间等4个关键热浪指数进行比较.结果显示,受全球变暖的影响,固定基线法(选择1951-1980年为气候背景计算相对阈值)倾向于提高当前热浪发生概率的估计,而变化基线法(以历史所有数据作为气候背景计算依据)和滑动基线法(以每年的前30 a数据作为基线计算依据)则能在一定程度上考虑温度平稳变化的影响;3种基线计算方法得到的热浪指数仅在绝对值上存在显著差异,而对于热浪指数长期变化趋势、空间分布规律等具有高度的一致性.基于生物在长期进化中具有适应环境的特点,建议采用滑动基线法将一段时期的气候态背景作为热浪判断依据,重点关注热浪造成的生物的响应和生态影响.

关键词：极端事件热浪定义逐日气温气候基线