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Spatial pattern and mechanisms of farmland abandonment in Agricultural and Pastoral Areas of Qingzang Plateau

Geography and Sustainability 2021年第3期2卷 139-150页

作者： Yuling Li Tao zhou Guanghui jiang Guangyong Li Dingyang zhou Yu Luo State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China School of Natural Resources Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China National Geomatics Center of China Beijing 100830China

With the rapid development of social economy and urban−rural integration,the phenomenon of farmland aban-donment worldwide has proved to be one of the main trends of land use and land cover change(LUCC),and profoundly affected the rural landscape and regional ecological *** by the natural environ-ment,economic development and backward agricultural technology,the phenomenon of farmland abandonment is also common in the Qingzang Plateau(QP).Therefore,this paper adopted the spatial autocorrelation method to analyze the spatial pattern of abandonment in the agricultural and pastoral areas of the Qingzang Plateau(APA−QP)in 2017,and the geographically weighted regression(GWR)model to explore the effects of geograph-ical resources,socio-economic development and location conditions on farmland *** study found that:1)From 2015 to 2017,the abandoned farmland area in the APA−QP was approximately 18.23×10^(4)ha,with an overall abandonment rate of 15.18%.On the whole,it showed the distribution characteristics of“strong in the south and weak in the north,strong in the east and weak in the west”.2)There were positive spatial correlation between both abandoned area and abandonment rate in the APA−QP,showing“concave”and“convex”patterns,respectively,mainly concentrated in the Huang−shui Valley and the Southeast Tibet;while in the western and northern regions,the degree of abandonment was relatively low.3)Farmland abandonment in the APA−QP was mainly driven by the geographical environment changes and farmers’decision−making on farmland *** was significant spatial heterogeneity on farmland abandonment associated with the impact of geographical resources,socio−economics and location *** geographical resource factors had a positive impact on the abandonment,and were strongly constrained by natural geographic conditions such as altitude and *** farmland resources in the Qingzang Plateau are limited,but are of strategic signifi

关键词： Farmland abandonment Spatial pattern Formation mechanism Geographically weighted regression Qingzang Plateau,Agricultural and pastoral areas

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A new series of two-photon polymerization initiators:Synthesis and nonlinear optical properties

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Science China Chemistry 2009年第12期52卷 2180-2185页

作者： GAN XiaoPing zhou HongPing SHI PengFei WANG Peng WU JieYing TIAN YuPeng YANG JiaXiang XU GuiBao zhou YuFang jiang MinHua Department of Chemistry Anhui University and Key Laboratory of Functional Inorganic Materials Chemistry of Anhui ProvinceHefei 230039China Department of Applied Chemistry School of ScienceAnhui Agriculture UniversityHefei 230036China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjing 210093China

Four photopolymerization initiators with D-π-D (D,donor; π,conjugation system) structure have been synthesized by solvent-free reaction and characterized by 1H NMR spectroscopy,IR and elemental analysis. The one-photon and two-photon excited fluorescence have been investigated in different solvents. Experimental results of the one-photon and two-photon absorption cross sections show different trends in OPA and TPA ability with different substitution groups in donor units.

关键词： two-photon absorption micro-fabrication polymerization solvent-free

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不同铁矿物对酱香型白酒封窖泥厌氧消化的影响

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应用化工 2024年第1期53卷 88-93页

作者：杨亚飞陈贺振周建国高小旭陈笔杨帆王岩王莉郑州大学生态与环境学院河南郑州450001 河南省环境与资源国际联合实验室河南郑州450001 贵州茅台酒股份有限公司贵州仁怀564501 河南省自然资源监测和国土整治院河南郑州450016

通过向废弃窖泥厌氧消化系统中分别添加强氧化性的水铁矿和弱氧化性但有导电性的磁铁矿,考察Fe(Ⅱ)、有机物、微生物群落结构等的变化,探究不同类型Fe(Ⅲ)矿物对窖泥厌氧消化的影响。结果表明,水铁矿组富集铁还原菌,Fe(Ⅱ)含量第12天迅... 详细信息

通过向废弃窖泥厌氧消化系统中分别添加强氧化性的水铁矿和弱氧化性但有导电性的磁铁矿,考察Fe(Ⅱ)、有机物、微生物群落结构等的变化,探究不同类型Fe(Ⅲ)矿物对窖泥厌氧消化的影响。结果表明,水铁矿组富集铁还原菌,Fe(Ⅱ)含量第12天迅速增加至900 mg/L,表明水铁矿发生了异化铁还原。磁铁矿组与对照组中Fe(Ⅱ)含量几乎一致,说明磁铁矿没有发生异化铁还原。水铁矿组和磁铁矿组中COD去除量分别比空白组增加了16.1%和4.9%,表明水铁矿和磁铁矿均促进了有机物的去除。磁铁矿组富集了Geobacter和Methanosarcina,促进了直接种间电子传递(DIET),增加了23.4%的甲烷产量,而水铁矿抑制甲烷化,降低了32.2%的甲烷产量。

关键词：厌氧消化 Fe(Ⅲ)矿物直接种间电子传递异化铁还原

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Fish Density Estimation with Multi-Scale Context Enhanced Convolutional Neural Network

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Journal of Communications and Information Networks 2019年第3期4卷 80-88页

作者： Yizhi zhou Hong Yu Junfeng Wu zhen Cui Hongshuai Pang Fangyan Zhang College of Information Engineering Dalian Ocean UniversityDalian 116023China Key Laboratory of Facility Fisheries Ministry of EducationDalian116023China

With the development of fishery industry,accurate estimation of the number of fish in aquaculture waters is of great importance to fish behavior analysis,bait feeding and fishery resource *** this paper,we propose a method for fish density estimation based on the multi-scale context enhanced convolutional network,which could map a fish school image taken at any angle to a density map,and calculate the number of fish in the image *** order to eliminate the influence of camera perspective effect and image resolution on density estimation,multi-scale filters are utilized in a convolutional neural network to process fish image in *** then,the context enhancement module is merged in the network structure to help the network understand the global context information of the ***,different feature maps are merged together to construct the density map of fish school images,and finally get the number of fish in the *** order to make the effectiveness of our method valid,we test the proposed method on *** results show that the proposed method has lower mean square error and mean absolute error,which is helpful to improve the accuracy of the fish counting in dense fish school images.

关键词： fish counting density estimation neural network context enhancement module

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城市“剩余空间”的更新利用——以温州鹿城区仰义街道桥下空间设计为例

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浙江建筑 2024年第5期41卷 27-32页

作者：罗莅文韩佳妮苏一楠周勇武李珍浙江省建筑设计研究院有限公司浙江杭州310006 杭州未来科技城(海创园)管委会浙江杭州311115 杭州余杭城市发展投资集团有限公司浙江杭州311121

在现代城市的快速发展过程中产生的剩余空间,其潜力与威胁同在。剩余空间更新常常是严重受限的,如今对其空间转化的探索仍在进行中。对此,研究整理了多种类型的城市多余空间类型,并试图从“桥下空间”这一特定类型出发,结合建筑设计的策... 详细信息

在现代城市的快速发展过程中产生的剩余空间,其潜力与威胁同在。剩余空间更新常常是严重受限的,如今对其空间转化的探索仍在进行中。对此,研究整理了多种类型的城市多余空间类型,并试图从“桥下空间”这一特定类型出发,结合建筑设计的策略,探索更为高效和积极利用的可能性。首先对剩余空间进行理论以及国内外案例的先行研究;而后以“温州鹿城区仰义街道的桥下空间设计项目”为重点,探讨这一研究的发生、发展与预期结果。由此探析“剩余空间”更新利用的可能性,辩证思考其功能植入后的未来前景。

关键词：剩余空间更新利用桥下空间

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防蛾灯对茶园主要蛾类害虫的防控效果评估

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中国植保导刊 2024年第3期44卷 63-68页

作者：蒋月丽周国涛张桦卢春光王振声乔利武予清河南省农业科学院植物保护研究所/河南省农作物病虫害防治重点实验室/农业农村部华北南部有害生物治理重点实验室河南郑州450002 河南云飞科技发展有限公司河南郑州450000 河南省洛阳市植物保护植物检疫站河南洛阳471000 信阳农林学院河南信阳464000

为评估防蛾灯对茶园主要蛾类害虫的防控效果,于2021年在贵州瓮安县和四川邛峡市两个地区的茶园开展防蛾灯防控效果评估。结果表明,贵州瓮安县茶园的茶尺蠖和茶毛虫每调查日的平均防效均在70%以上,茶尺蠖的最高防效达91.67%,茶毛虫的最... 详细信息

为评估防蛾灯对茶园主要蛾类害虫的防控效果,于2021年在贵州瓮安县和四川邛峡市两个地区的茶园开展防蛾灯防控效果评估。结果表明,贵州瓮安县茶园的茶尺蠖和茶毛虫每调查日的平均防效均在70%以上,茶尺蠖的最高防效达91.67%,茶毛虫的最高防效为93.77%。四川邛峡市茶园,茶尺蠖、茶毛虫和茶细蛾3种蛾类害虫在大部分调查日的防效在50%以上,平均最高防效分别达65.33%、66.67%、80.00%。距离光源不同调查点之间的防效差异显著分析显示,贵州瓮安县茶园在5、10m和15m之间差异不明显,四川邛峡市茶园在大部分调查日期差异明显,距离光源越近防效越好。该研究结果为防蛾灯在茶园的应用和推广提供了必要的参考依据。

关键词：防蛾灯茶园蛾类害虫防控效果

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壮医三气养生操对慢性心力衰竭患者的影响

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中国中医药现代远程教育 2024年第3期22卷 74-76页

作者：姜益宏曾海飞周伟民李莲周宇桢魏月媚广西国际壮医医院心病科广西南宁530201 广西国际壮医医院肾病科广西南宁530201

目的探讨壮医三气养生操对慢性心力衰竭(CHF)患者的影响。方法 CHF患者120例随机分为干预组、对照组,每组60例,对照组给予常规药物治疗,干预组在常规药物治疗基础上加壮医三气养生操导引运动;测定2组治疗前后6 min步行试验距离、纽约... 详细信息

目的探讨壮医三气养生操对慢性心力衰竭(CHF)患者的影响。方法 CHF患者120例随机分为干预组、对照组,每组60例,对照组给予常规药物治疗,干预组在常规药物治疗基础上加壮医三气养生操导引运动;测定2组治疗前后6 min步行试验距离、纽约心脏病学会(NYHA)心功能分级、左心射血分数(LVEF)、N末端B型利钠肽原(NT-proBNP)、中医证候积分。结果干预组和对照组均能显著改善患者的6 min步行试验距离、降低NT-proBNP水平、改善中医证候积分(P0.05)。结论壮医三气养生操能改善CHF患者的疗效。

关键词：壮医三气养生操慢性心力衰竭心功能心脏康复

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鼻部朗格汉斯细胞组织细胞增生症一例

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中国麻风皮肤病杂志 2024年第7期40卷 504-505页

作者：姜雨蒙周钟莲陈明亮李芳芳谢红付黄莹雪中南大学湘雅医院皮肤科湖南长沙410008

朗格汉斯细胞组织细胞增生症(LCH)是一种罕见的克隆性增生性疾病,可累及包括皮肤在内的多个系统,皮肤表现往往为诊断提供重要线索。本文报道一例鼻部赘生物的男性患者,经皮肤活检和免疫组织化学确诊为LCH,后进一步发现患者同时伴骨骼等... 详细信息

朗格汉斯细胞组织细胞增生症(LCH)是一种罕见的克隆性增生性疾病,可累及包括皮肤在内的多个系统,皮肤表现往往为诊断提供重要线索。本文报道一例鼻部赘生物的男性患者,经皮肤活检和免疫组织化学确诊为LCH,后进一步发现患者同时伴骨骼等多系统受累。

关键词：朗格汉斯细胞组织细胞增生症玫瑰痤疮骨骼 CD1a

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Flotation and adsorption of quaternary ammonium salts collectors on kaolinite of different particle size

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International Journal of Mining Science and Technology 2013年第2期23卷 255-259页

作者： jiang Hao Liu Guorong Hu Yuehua Xu Longhua Yu Yawen Xie zhen Chen Haochuan School of Resources Processing and Bioengineering Central South University Key Laboratory of Solid Waste Treatment and Resource Recycle of Ministry of Education Southwest University of Science and Technology

The flotation behaviors of decyltrimethylammonium (103C), dodecyltrimethylammonium chloride (DTAC), tetradecyltrimethylammonium chloride (TTAC) and cetyltrimethylammonium chloride (CTAC) on kaolinite of different particle size fraction were studied. The adsorbed amount and adsorption isotherms of collectors on kaolinite were determined for painstaking investigation into the adsorption of quaternary amines at kaolinite-water interface by ultraviolet spectrophotometer methods. The flotation results show that the flotation recovery of kaolinite of different particle fraction increases with an increase in pH when 103C, DTAC, TTAC and CTAC are used as collectors. As the concentration of collectors increases, the flotation recovery increases. Particle size of kaolinite has a strong effect on flotation. The flotation recovery of fine kaolinite decreases with the carbon chain of quaternary ammonium salts collectors increasing, while coarse kaolinite is on the contrary. The adsorbed amount tests and adsorption isotherms show that adsorbed amount increases when the particle size of kaolinite increases or when the carbon chain length of quaternary ammonium salts increases. Within the range of flotation collector concentration, the longer the hydrocarbon chain, the more probable to be absolutely adsorbed by fine kaolinite particles and then the lower the collector concentration in the bulk, which leds to lower flotation recovery.

关键词： Kaolinite Particle size Quaternary ammonium salts Flotation Adsorption

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V2O5 Nanospheres with Mixed Vanadium Valences as High Electrochemically Active Aqueous Zinc-Ion Battery Cathode

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Nano-Micro Letters 2019年第2期11卷 98-108页

作者： Fei Liu Zixian Chen Guozhao Fang Ziqing Wang Yangsheng Cai Boya Tang jiang zhou Shuquan Liang School of Materials Science and Engineering Central South UniversityChangsha 410083HunanPeople’s Republic of China Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South UniversityChangsha 410083HunanPeople’s Republic of China

AV4+-V2O5 cathode with mixed vanadium valences was prepared via a novel synthetic method using VOOH as the precursor,and its zinc-ion storage performance was *** products are hollow spheres consisting of *** V4+-V2O5 cathode exhibits a prominent cycling performance,with a specific capacity of 140 mAhg-1 after 1000 cycles at 10 A g.1,and an excellent rate *** good electrochemical performance is attributed to the presence of V4+,which leads to higher electrochemical activity,lower polarization,faster ion diffusion,and higher electrical conductivity than V2O5 without V4+.This engineering strategy of valence state manipulation may pave the way for designing high-performance cathodes for elucidating advanced battery chemistry.

关键词： V2O5 Mixed valences Hollow sphere Long-cycle-life Aqueous zinc-ion battery

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