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基于社会-生态功能复合与SPCA的城市绿地生态网络重要源地识别

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中国园林 2024年第2期40卷 117-123页

作者：仲启铖张桂莲张浪上海市园林科学规划研究院林业科学研究所上海200232 上海市园林科学规划研究院林业碳汇计量监测中心上海200232 住房和城乡建设部科技委园林绿化专委会上海市园林科学规划研究院上海200232 上海城市困难立地绿化工程技术研究中心上海200232

构建基于社会-生态功能复合的城市生态源地综合评价指标体系,以上海市闵行区城市绿地为对象,运用GIS、RS、Invest及景观连接度模型等方法计算指标,采用SPCA确定指标权重,通过空间加权计算和重分类识别重要源地。结果表明:(1.在424个备... 详细信息

构建基于社会-生态功能复合的城市生态源地综合评价指标体系,以上海市闵行区城市绿地为对象,运用GIS、RS、Invest及景观连接度模型等方法计算指标,采用SPCA确定指标权重,通过空间加权计算和重分类识别重要源地。结果表明:(1.在424个备选源地中,极重要、重要、一般、不重要和极不重要等级面积占比分别为1..2%、1..1.、25.3%、23.0%和1..4%;(2)共识别极重要、重要源地1.9个,总面积1..61.m^(2),平均面积0.1.4km^(2),占备选源地总面积的35.6%,占全区总面积的5.0%;(3)区域绿地是重要源地的主体,其次是公园绿地和附属绿地;(4)在规划实践中,可依托区域绿地开展绿林农湿多要素复合,提升源地总体规模和服务功能。研究成果可为上海及长三角其他城市精准识别城市绿地生态网络重要源地提供借鉴。

关键词：风景园林城市绿地生态网络生态源地社会-生态功能景观连接度

Corrosion fatigue behavior of fastening hole structure and virtual crack propagation tests

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Journal of University of Science and Technology Beijing 2008年第5期15卷 585-589页

作者： Youhong Zhang Xinlong Chang Guozhi Lv Hui wang {1. Li Yueliang Cheng The Second Artillery Engineering College Xi＇an 710025 China School of Aeronautics Northwest Polytechnical University Xi＇an 710072 China Naval Aeronautical Engineering Academy Qingdao Branch Qingdao 266041 China

The fatigue crack propagation behavior of the LY1.CZ aluminum alloy fastener involving a central hole in air or in 3.5wt% NaCl solution was investigated. The experimental results indicated that the corrosion fatigue crack growth rate decreased with the increasing loading frequency,and in a corrosive environment,the crack growth rate was slightly larger than that in air. Based on the experimental results,the virtual corrosion fatigue crack propagation tests were investigated and the stochastic process method and the AFGROW simulation method were presented. The normal process and lognormal process were considered for the stochastic process method based on the numerically fitted Paris equation. The distribution of crack size and the corresponding probabilistic model of crack length distribution for a given number of cycles can be found by integrating the stochastic process over time. Using the AFGROW software,the virtual simulation was carried out to analyze the corrosion fatigue crack growth behavior and the predicted crack growth curve was in good agreement with the experimental results.

关键词： aluminum alloy corrosion fatigue crack propagation stochastic process AFGROW

基于长短时记忆网络的山区中小流域降雨径流模拟

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水电能源科学 2024年第8期42卷 33-37页

作者：张锦堂任明磊李京兵唐榕钟小燕王刚王玉丽安徽省水文局安徽合肥230022 中国水利水电科学研究院北京100038 水利部防洪抗旱减灾工程技术研究中心(水旱灾害防御中心) 北京100038

洪水预报是流域防洪减灾的重要非工程措施之一。目前我国中小河流暴雨洪水灾害频发,但应对短历时强降雨的洪水预报能力仍不强。以安徽省东部山区中小流域为研究对象,引入长短时记忆网络建立流域降雨径流模型,探讨其在山区中小流域的洪... 详细信息

洪水预报是流域防洪减灾的重要非工程措施之一。目前我国中小河流暴雨洪水灾害频发,但应对短历时强降雨的洪水预报能力仍不强。以安徽省东部山区中小流域为研究对象,引入长短时记忆网络建立流域降雨径流模型,探讨其在山区中小流域的洪水模拟效果。结果表明,考虑降雨输入的空间差异可提升深度学习模型降雨径流模拟预测性能,且长短时记忆网络能够取得优于传统人工神经网络的精度;长短时记忆网络模型有效建立了流域降雨与径流间的复杂非线性关系,模型在所选流域内场次洪水的峰值模拟效果较好,训练、测试集场次洪水峰值合格率均在90%以上;长短时记忆网络内部结构特征与流域水文过程具有较好的相似性,对山区中小流域暴雨洪水非线性关系拟合效果突出。

关键词：山丘区长短时记忆网络中小河流降雨径流模拟

Effect of pine foliage damage on the incidence of larval diapause in the pine caterpillar Dendrolimus punctatus （Lepidoptera： Lasiocampidae）

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Insect Science 2008年第5期15卷 441-445页

作者： Li-Li Huang Guo-Hong wang {1. He Feng Ge State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing Key Laboratory of Developmental Biology and Neurobiology College of Life Sciences Fujian Normal University Fuzhou China

The pine caterpillar Dendrolimus punctatus （Walker） with a larval facultative diapause is one of the most destructive insect pests of the pine tree Pinus massoniana in China. The larvae feeding on pine trees with different damage levels were studied to determine the induction of diapause under both laboratory and field conditions. Developmental duration of larvae before the third instar was the longest when fed with 75%-90% damaged needles, followed by 25%-40% damaged needles and intact pine needles, whereas mortalities did not differ among different treatments under the conditions of 25℃ and critical photoperiod 1..5：1..5 L：D. At 25 ℃, no diapause was induced under 1.：9 L：D, whereas 1.0% diapause occurred under 1.：1. L：D regardless of the levels of needle damage. Incidences of larvae entering diapause when they were fed with intact, 25%-40% and 75%- 90% damaged pine needles were 51.7%, 70.8% and 81. under 1..5：1..5 L：D, respectively. Similar results were obtained in the field experiment. Incidence of diapause was significantly different among the pine needle damage levels of pine trees when the photoperiod was close to the critical day length, indicating that the effect of host plants on diapause induction was dependent on the range of photoperiod. The content of amino acid and sugar decreased and tannin increased in pine needles after feeding by the pine caterpillars, suggesting that changed levels of nutrients in damaged needles or a particular substance emitted by damaged pine trees was perhaps involved in the diapause induction of the pine caterpillar.

关键词： Dendrolimus punctatus diapause induction leaf damage photoperiod Pinus massoniana

Beijing Matrix Technologies introduces revolutionary insulation material Y-Warm

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China Textile 2024年第4期 35-35页

作者： zhong Mengxia 不详

Since the discovery of nanoporous materials (aerogel)in 1.31.there is no doubt that this material is classified as a super-insulator with the highest insulation value of any known material with the lowest thermal conductivity value of any ***,the application of aerogel is severely limited due to the difficulty of *** eight years of research and efforts,Beijing Matrix Technologies Co.,*** met the world challenge on the combination of mechanical strength and thermal insulation.

关键词： insulation doubt material

Quantitative Evaluation of Sustainable Development and Eco-Environmental Carrying Capacity in Water-Deficient Regions:A Case Study in the Haihe River Basin,China

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Journal of Integrative Agriculture 2014年第1期13卷 195-206页

作者： wang {1.-gen LUO Yu-zhou ZHANG Ming-hua XIA Jun Key Laboratory of Water Cycle & Related Land Surface Processes/Institute of Geographical Science and Natural Resources Research Chinese Academy of Sciences Department of Land Air and Water ResourcesUniversity of California

Quantitative assessment of development sustainability could be a challenge to regional management and planning, especially for areas facing great risks of water shortage. Surface-water decline and groundwater over-pumping have caused serious environmental problems and limited economic development in many regions all around the world. In this paper, a framework for quantitatively evaluating development sustainability was established with water-related eco-environmental carrying capacity （EECC） as the core measure. As a case study, the developed approach was applied to data of the Haihe River Basin, China, during 1.98 through 2007. The overall sustainable development degree （SDD） is determined to be 0.39, suggesting that this rate of development is not sustainable. Results of scenario analysis revealed that overshoot, or resource over- exploitation, of the Basin＇s EECC is about 20% for both population and economy. Based on conditions in the study area in 2007, in order to achieve sustainable development, i.e., SDD〉0.70 in this study, the EECC could support a population of 1.8 million and gross domestic product （GDP） of 2.72 trillion CNY. The newly developed approach in quantifying ecoenvironmental carrying capacity is anticipated to facilitate sustainable development oriented resource management in waterdeficient areas.

关键词： eco-environmental carrying capacity development scenario Haihe River Basin sustainable development waterresources

Crossing point temperature of coal

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Mining Science and Technology 2011年第2期21卷 255-260页

作者： Qi xuyao Deming wang James A. Milke Xiaoxing {1. State Key Laboratory of Coal Resources and Safe Mining Faculty of Safety Engineering China University of Mining ＆ Technology Xuzhou 221008 China Department of Fire Protection Enguneering University of Maryland College Park MD20742 USA

A further understanding of the self-heating of coal was obtained by investigating the crossing point temperature（CPT） of different ranks of *** tests were carried out using a self-designed experimental system for coal self-heating.50 g（±0.01.g） of coal particles ranging from 0.1. mm to 0.38 mm in size were put into a pure copper reaction vessel attached to the center of a temperature programmed *** temperature program increased the temperature at a rate of 0.8℃/*** air was permitted to flow into the coal reaction vessel at different *** surrounding temperature and the coal temperature were monitored by a temperature *** results indicate that CPT is affected by coal rank,moisture,sulfur, and the experimental *** ranked coals show higher CPT values.A high moisture content causes a delay phenomenon during the self-heating of the *** at 40℃decreases the effects of *** reactivity of sulfur components in the coal is low under dry and low-temperature conditions. These components form a film that covers the coal surface and slightly inhibits the self-heating of the coal. The flow rate of dry air,and the heating rate of the surroundings,also affect the self-heating of the *** most appropriate experimental conditions for coal samples of a given weight and particle size were determined through contrastive *** on this analysis we propose that CPTs be determined under the same,or nearly the same conditions,for evaluation of the spontaneous combustion of coal.

关键词： Coal Spontaneous combustion Crossing point temperature Moisture Sulfur Coal rank

芳烃官能化有机硅膜的制备及丙烯/丙烷分离性能

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化工进展 2024年第3期43卷 1428-1435页

作者：钱俊明郭猛任秀秀余亮钟璟徐荣常州大学石油化工学院常州大学精细石油化工江苏省重点实验室江苏常州213164 北京理工大学前沿交叉科学研究院北京100081

利用具有单苯和联苯桥联结构的有机硅前体1.4-二(三乙氧基硅基)苯(BTESB)和4,4'-二(三乙氧基硅基)联苯(BTESBPh),通过溶胶-凝胶法制备成有机硅膜并应用于丙烯/丙烷分离。在25℃时,BTESB膜的C_(3)H_(6)渗透速率为3.4×1.^(-9)mol/(m^(2)... 详细信息

利用具有单苯和联苯桥联结构的有机硅前体1.4-二(三乙氧基硅基)苯(BTESB)和4,4'-二(三乙氧基硅基)联苯(BTESBPh),通过溶胶-凝胶法制备成有机硅膜并应用于丙烯/丙烷分离。在25℃时,BTESB膜的C_(3)H_(6)渗透速率为3.4×1.^(-9)mol/(m^(2)·s·Pa),C_(3)H_(6)/C_(3)H_(8)选择性为9.6;BTESBPh膜的C_(3)H_(6)渗透速率为1.7×1.^(-8)mol/(m^(2)·s·Pa),C_(3)H_(6)/C_(3)H_(8)选择性为1..5。具有联苯桥联结构的BTESBPh膜网络结构更为疏松,可获得更高的气体渗透速率。苯环中大π键与待分离组分C_(3)H_(6)中的碳碳双键产生π-π相互作用,有利于C_(3)H_(6)组分的优先吸附和渗透。而BTESBPh中联苯结构增强了这一过程,表现为低温测试条件下,BTESBPh膜的C_(3)H_(6)/C_(3)H_(8)选择性略高于BTESB膜。本研究可为高性能丙烯/丙烷气体分离膜的开发提供参考。

关键词：有机硅膜孔径丙烯/丙烷分离溶胶-凝胶法分子筛分

High power triboelectric nanogenerator based on printed circuit board （PCB） technology

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Nano Research 2015年第3期8卷 722-730页

作者： Changbao Han Chi Zhang Wei Tang Xiaohui Li zhong Lin {1. Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences Beijing 100083 China School of Material Science and Engineering Georgia Institute of Technology Atlanta Georgia 30332 USA

Harvesting mechanical energy from our surroundings to acquire a steady and high power output has attracted intensive interest due to the fast development of portable electronics. In this work the disk-structured triboelectric nanogenerator （TENG） was prepared based on the mature printed drcuit board （PCB） technology and the composite structure for effectively improving the utilization in space. A narrow grating of 1. was designed to produce high output. Operated at a rotation rate of 1.000 rpm, the TENG produces a high output power density of 267 mW/cm2 （total power output of 25.7 W） at a matched load of 0.93 MfZ After introducing a transformer, the output power can be managed so that it can be directly used to charge a battery for a smart phone. With the PCB production technology, fabrication of high performance TENG at low cost and large-scale becomes feasible.

关键词： triboelectric nanogenerator(TENG) printed circuit board (PCB) output power transformer