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Leverage or crowd out:the National Independent Innovation Demonstration Zone policies and green innovation efficiency of enterprises
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作者 Haonan He Jiaxin Sun +2 位作者 Richard Samuel Freeman Dehong Li Shanyong Wang 《中国科学技术大学学报》 北大核心 2025年第1期32-44,31,I0001,共15页
The National Independent Innovation Demonstration Zone has been assigned the unique mission of demonstrating and leading national innovation and playing a key supportive role in enhancing green innovation.Based on the... The National Independent Innovation Demonstration Zone has been assigned the unique mission of demonstrating and leading national innovation and playing a key supportive role in enhancing green innovation.Based on the sample data of A-share listed companies in China from 2007 to 2021,we apply a multi-period difference-in-differences model to analyze whether the implementation of the National Independent Innovation Demonstration Zone policies plays a leverage effect or a crowd out effect on the green innovation efficiency of enterprises and systematically test the regulatory mechanism of government grants and media attention in the process of this influence.The empirical results show that the imple-mentation of the National Independent Innovation Demonstration Zone policies has a positive impact on the green innovation efficiency of enterprises and that the green innovation induced by this reform is not the leverage effect of additional R&D investment on the basis of the existing innovation activities of enterprises but rather the result of the reallocation of resources to crowd out existing non-green innovation.It is further found that government grants and media attention positively moderate the positive driving effect of National Independent Innovation Demonstration Zone policies on the green innovation efficiency of enterprises. 展开更多
关键词 National Independent Innovation Demonstration zone policies green innovation efficiency leverage effect crowd out effect
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Femtosecond laser modulated into Bessel beam by spatial light modulator for Fresnel zone plate processing
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作者 DUAN Lian ZHOU Fang +3 位作者 KONG De-jian ZHANG Fan SUN Xiao-yan DUAN Ji-an 《Journal of Central South University》 2025年第2期469-482,共14页
Femtosecond laser processing is an important machining method for micro-optical components such as Fresnel zone plate(FZP).However,the low processing efficiency of the femtosecond laser restricts its application.Here,... Femtosecond laser processing is an important machining method for micro-optical components such as Fresnel zone plate(FZP).However,the low processing efficiency of the femtosecond laser restricts its application.Here,a femtosecond laser Bessel beam is proposed to process micro-FZP,which is modulated from a Gaussian beam to a Bessel annular beam.The processing time for FZP with an outer diameter of 60μm is reduced from 30 min to 1.5 min on an important semiconductor material gallium arsenide(GaAs),which significantly improves the processing efficiency.In the modulation process,a central ablation hole that has an adverse effect on the diffraction performance is produced,and the adverse effect is eliminated by superimposing the blazed grating hologram.Meanwhile,the FZP machined by spatial light modulator(SLM)has good morphology and higher diffraction efficiency,which provides a strong guarantee for the application of micro-FZP in computed tomography and solar photovoltaic cells. 展开更多
关键词 femtosend laser Fresnel zone plate spatial light modulator Bessel beam GAAS
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Determining the parameters and chemical behaviour of the overdriven detonation reaction zone of CL-20-based aluminized explosives
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作者 Moyan Liu Yan Liu +3 位作者 Fan Bai Hongfu Wang Shanyong Chu Fenglei Huang 《Defence Technology(防务技术)》 2025年第5期46-66,共21页
The new CL-20(hexanitrohexaazaisowurtzitane)type aluminized explosives in the overdrive detonation(ODD)conditions of the core problem is how to accurately represent the state of the overdrive detonation products.To th... The new CL-20(hexanitrohexaazaisowurtzitane)type aluminized explosives in the overdrive detonation(ODD)conditions of the core problem is how to accurately represent the state of the overdrive detonation products.To this end,this paper is based on the impedance matching method to test the ODD conditions of CL-20 type aluminium explosive particle velocity.Calculated the interfacial pressure of the shock wave in different media.Determined the characteristic parameters of the reaction zone of the detonation of CL-20 aluminized explosives.Calibrated the parameters of the JoneseWilkinseLee(JWL)+γ equation for the detonation products(DPs).Revealed the effect of different DPs equation of state(EOS)on the Hugoniot pressure of ODD.The results indicate that when the content of aluminum powder ranges from 0%to 30%,the duration of the ODD reaction zone and the width of the detonation reaction zone of the CL-20-based aluminized explosive are directly proportional to the content of aluminum powder.The width of the detonation reaction zone is increased by 1.97 times to 2.7 times compared to that of the reaction zone without the addition of aluminum powder.However,the energy release efficiency of the detonation reaction zone is inversely proportional to the content of aluminum powder.When the aluminum powder content was held constant,the incorporation of AP caused a 25%reduction in the energy release efficiency of the detonation reaction zone.Compared with existing ODD state equations,the JWL +γ equation is superior in calibrating overpressure Hugoniot data and the isentropic expansion in the C-J state.The deviation between calculated pressure results and experimental measurements is within 6%. 展开更多
关键词 Equation of state for ODD CL-20-based aluminized explosives Detonation reaction zone Impedance matching Interfacial particle velocity
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海岸带地下水循环及其环境效应研究进展与展望
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作者 韩冬梅 曹国亮 +1 位作者 萧怡 宋献方 《地学前缘》 北大核心 2026年第1期384-404,共21页
海岸带地下水循环是陆海交互带水动力过程与生态环境演化的关键环节,其动态演变受自然与人类活动的双重驱动,并对沿海地区的资源、生态与可持续发展产生深远影响。本文系统综述了滨海地下水循环及其环境效应的研究进展,重点探讨了以下内... 海岸带地下水循环是陆海交互带水动力过程与生态环境演化的关键环节,其动态演变受自然与人类活动的双重驱动,并对沿海地区的资源、生态与可持续发展产生深远影响。本文系统综述了滨海地下水循环及其环境效应的研究进展,重点探讨了以下内容:海岸带水循环的多尺度过程,包括地表水地下水相互作用、潮汐驱动下的地下水流动态及陆海界面水文交换;地下水循环演变的驱动要素,涵盖气候变化(包括降水格局改变、海平面上升)、人类活动(包括人口经济增长、土地利用变化、流域水资源开发)以及地质地貌的控水机制;地下水文过程引发的环境效应,包括营养物质与污染物迁移对近岸水质的调控、海水入侵与土壤盐渍化的生态威胁、海底地下水排泄(SGD)对海洋碳\\氮循环的贡献,以及超采引发的地面沉降灾害;阐释了我国海岸带相关的环境效应特征。提出未来研究应加强高分辨率监测、多过程耦合模拟、人地系统协同管理与碳中和背景下的生态效应评估,支撑海岸带水资源安全保障与生态保护战略实施。 展开更多
关键词 海岸带 地下水循环 海水入侵 海底地下水排泄 环境效应 海岸带管理
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我国岩溶生态水文学研究进展与展望
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作者 蒋忠诚 罗为群 +2 位作者 吴泽燕 章程 邹胜章 《地学前缘》 北大核心 2026年第1期342-353,共12页
20世纪末以来,我国南方表层岩溶水与石漠化综合治理的相关性研究推动了我国生态水文学的形成与发展。取得的突出研究进展包括:(1)是开展了高度依赖地下水的岩溶生态系统研究,岩溶生态系统普遍发育浅根系和深根系这二态根系,有的深根可达... 20世纪末以来,我国南方表层岩溶水与石漠化综合治理的相关性研究推动了我国生态水文学的形成与发展。取得的突出研究进展包括:(1)是开展了高度依赖地下水的岩溶生态系统研究,岩溶生态系统普遍发育浅根系和深根系这二态根系,有的深根可达100多m,完全依赖岩溶地下水,但依赖程度因水文地质条件而异。(2)是生态系统对岩溶水的调蓄功能研究,生态系统对表层岩溶带水资源具有调蓄功能,特别是水源林对于表层岩溶水资源的涵养具有重要价值,使表层岩溶泉成为西南岩溶山区居民分散供水的主要水源;此外,生态调控促进了岩溶水资源的可持续利用。(3)是岩溶关键带结构及生态水文模型研究,阐明了岩溶关键带及结构的特点,建立了岩溶生态水文耦合模型,推动岩溶区水资源调控和水土漏失有效防治。岩溶关键带“六水循环”、岩溶关键带生态水文监测网络、极端气候和人类干扰下岩溶生态水文的响应过程是下一步的重要研究方向。 展开更多
关键词 岩溶 生态水文学 水文地质 岩溶关键带 中国
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基于TrustZone的可信移动终端云服务安全接入方案 被引量:29
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作者 杨波 冯登国 +1 位作者 秦宇 张英骏 《软件学报》 EI CSCD 北大核心 2016年第6期1366-1383,共18页
可信云架构为云计算用户提供了安全可信的云服务执行环境,保护了用户私有数据的计算与存储安全.然而在移动云计算高速发展的今天,仍然没有移动终端接入可信云服务的安全解决方案.针对上述问题,提出了一种可信移动终端云服务安全接入方案... 可信云架构为云计算用户提供了安全可信的云服务执行环境,保护了用户私有数据的计算与存储安全.然而在移动云计算高速发展的今天,仍然没有移动终端接入可信云服务的安全解决方案.针对上述问题,提出了一种可信移动终端云服务安全接入方案.方案充分考虑了移动云计算应用背景,利用ARM Trust Zone硬件隔离技术构建可信移动终端,保护云服务客户端及安全敏感操作在移动终端的安全执行.结合物理不可克隆函数技术,给出了移动终端密钥与敏感数据管理机制.在此基础上,借鉴可信计算技术思想设计了云服务安全接入协议.协议兼容可信云架构,提供云服务端与移动客户端间的端到端认证.分析了方案具备的6种安全属性,给出了基于方案的移动云存储应用实例,实现了方案的原型系统.实验结果表明:可信移动终端TCB较小,方案具有良好的可扩展性和安全可控性,整体运行效率较高. 展开更多
关键词 移动云计算 可信计算 可信移动终端 安全接入 Trust zone 物理不可克隆函数(PUF)
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Holocene activities of the Taigu fault zone, Shanxi Province, and their relations with the 1303 Hongdong M=8 earthquake 被引量:23
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作者 谢新生 江娃利 +1 位作者 王焕贞 冯西英 《地震学报》 CSCD 北大核心 2004年第3期281-293,共13页
The Taigu fault zone is one of the major 12 active boundary faults of the Shanxi fault-depression system, located on the eastern boundary of the Jinzhong basin. As the latest investigation indicated, the fault zone ha... The Taigu fault zone is one of the major 12 active boundary faults of the Shanxi fault-depression system, located on the eastern boundary of the Jinzhong basin. As the latest investigation indicated, the fault zone had dislocated gully terrace of the first order, forming fault-scarp in front of the loess mesa. It has been discovered in many places in ground surface and trenches that Holocene deposits were dislocated. The latest activity was the 1303 Hongdong earthquake M=8, the fault appeared as right-lateral strike-slip with normal faulting. During that earthquake, the Taigu fault together with the Mianshan western-side fault on the Lingshi upheaval and the Huoshan pediment fault on the eastern boundary of the Linfen basin was being active, forming a surface rupture belt of 160 km in length. Moreover, the Taigu fault were active in the mid-stage of Holocene and near 7 700 aB.P. From these we learnt that, in Shanxi fault-depression system, the run-through activity of two boundary faults of depression-basins might generate great earthquake with M=8. 展开更多
关键词 太谷断裂 全新世活动 1303年洪洞地震 地表破裂带
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Assessing current faulting behaviors and seismic risk of the Anninghe-Zemuhe fault zone from seismicity parameters 被引量:106
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作者 易桂喜 闻学泽 +1 位作者 范军 王思维 《地震学报》 CSCD 北大核心 2004年第3期294-303,共10页
Using the data of regional seismic network, this paper analyzes the current faulting behaviors of different segments of the Anninghe-Zemuhe fault zone, western Sichuan, and identifies the likely risky segments for pot... Using the data of regional seismic network, this paper analyzes the current faulting behaviors of different segments of the Anninghe-Zemuhe fault zone, western Sichuan, and identifies the likely risky segments for potential large earthquakes. The authors map the probable asperities from the abnormally low b-value distribution, develop and employ a method for identifying current faulting behaviors of individual fault segment from the combinations of multiple seismicity parameter values, and make an effort to estimate the average recurrence intervals of character-istic earthquakes by using the parameters of magnitude-frequency relationship of the asperity segment. The result suggests that the studied fault zone contains 5 segments of different current faulting behaviors. Among them, the Mianning-Xichang segment of the Anninghe fault has been locked under high stress, its central part is probably an asperity with a relatively large scale. The Xichang-Puge segment of the Zemuhe fault displays very low seismicity under low stress. Both the locked segment and the low-seismicity segment can be outlined on the across-profile of relocated hypocenter depths. The Mianning-Xichang segment is identified to be the one with potential large earth-quake risk, for which the average recurrence interval between the latest M = 6.7 earthquake in 1952 and the next characteristic event is estimated to be 55 to 67 years, and the magnitude of the potential earthquake between 7.0 and 7.5. Also, it has been preliminarily suggested that for a certain fault segment, its faulting behaviors may change and evolve with time gradually. 展开更多
关键词 地震活动参数 断裂活动 习性 凹凸体潜在地震危险性 安宁河—则木河断裂带
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KarstHyporheicZone及其研究进展 被引量:5
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作者 蒲俊兵 袁道先 《中国岩溶》 CAS CSCD 2013年第1期7-13,共7页
Karst Hyporheic Zone(笔者将之译为"岩溶交互带")是近三年来新出现的一个岩溶术语,我国尚未开展"岩溶交互带"的研究工作,它主要是指岩溶地下水与周边岩溶基质(含沉积物、基岩)水之间物质能量活跃交替的地带。本文... Karst Hyporheic Zone(笔者将之译为"岩溶交互带")是近三年来新出现的一个岩溶术语,我国尚未开展"岩溶交互带"的研究工作,它主要是指岩溶地下水与周边岩溶基质(含沉积物、基岩)水之间物质能量活跃交替的地带。本文从"岩溶交互带"的概念来源、含义、最新的研究进展和监测技术发展等方面进行了总结,并就现存的问题和未来研究提出了看法。 展开更多
关键词 “岩溶交互带” 岩溶术语 科学意义
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基于联合熵隐私保护的自适应动态Mix-zone方案 被引量:4
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作者 冯霞 刘亚伟 《通信学报》 EI CSCD 北大核心 2018年第3期76-85,共10页
针对车联网中Mix-zone方案灵活性低以及隐私保护程度对用户缺乏透明度的问题,提出一种交通自适应的动态Mix-zone创建方法,可以根据道路交通状况为车辆动态创建Mix-zone,随时随地为车辆创建Mix-zone进行假名更换,建立基于身份和位置的隐... 针对车联网中Mix-zone方案灵活性低以及隐私保护程度对用户缺乏透明度的问题,提出一种交通自适应的动态Mix-zone创建方法,可以根据道路交通状况为车辆动态创建Mix-zone,随时随地为车辆创建Mix-zone进行假名更换,建立基于身份和位置的隐私保护;提出对Mix-zone进行隐私分级的联合熵度量模型,可通过归一化的定量计算结果度量Mix-zone达到当前区域车辆隐私需求的程度。使用深圳市某区的出租车辆的轨迹数据验证了联合熵隐私度量模型及基于该模型的Mix-zone创建方案,实验结果表明,该联合熵模型能刻画交通场景中参数与隐私保护程度的正比关系,在联合熵所表示的无序性指标上,所提Mix-zone创建方案相较其他方案,具有更好的隐私保护效果。 展开更多
关键词 车联网 Mix-zone 联合熵 隐私保护
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永久基本农田保护片区智能识别系统iZone的建立与应用 被引量:7
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作者 马世发 吴楷钊 +3 位作者 劳春华 钟远军 张婷 黄韬 《农业工程学报》 EI CAS CSCD 北大核心 2017年第2期276-282,共7页
永久基本农田划定是当前国土资源管理一项十分重要而紧迫的任务,其对维护粮食安全和控制城镇无序增长具有重要意义。永久基本农田划定不仅要满足耕地质量较高而且还要集中连片,更需要协调城镇化矛盾。因此,如何从土地利用现状数据库中... 永久基本农田划定是当前国土资源管理一项十分重要而紧迫的任务,其对维护粮食安全和控制城镇无序增长具有重要意义。永久基本农田划定不仅要满足耕地质量较高而且还要集中连片,更需要协调城镇化矛盾。因此,如何从土地利用现状数据库中提取永久基本农田保护图斑实际上是一个复杂的空间数据挖掘过程。研究利用农用地分等成果定义保护片区质量,利用元胞自动机模拟分析土地利用矛盾,利用种子扩充算法进行保护片区搜索,利用神经网络进行耕地保护压力预警。基于C#和Arc Engine10.1将多种空间数据挖掘模型进行集成,构成了面向全域永久基本农田识别的智能系统工具包iZone,并在广东省高要区金利镇进行实例应用。研究表明,iZone能按既定规则从土地利用现状数据库中提取保护图斑,有效避免了人为划定的过多主观性,并且能获得与人工方案相当乃至更好的表现。iZone利用复杂地理计算技术进行永久基本农田智能识别,可提高永久基本农田划定工作的科学性。 展开更多
关键词 土地利用 区划 识别 永久基本农田 农用地利用等别 元胞自动机 种子搜索 人工神经网络
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基于DOM树和递归X-Y分割算法的Zone树模型 被引量:4
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作者 黄歆 桑楠 《计算机工程》 CAS CSCD 北大核心 2009年第5期53-55,共3页
在分析DOM树的基础上提出一种基于DOM树和递归X-Y分割算法,可以根据网页的几何布局生成Zone树模型。描述了将Zone树模型和递归X-Y算法应用到文献数据检索的优越性,给出构建Zone树模型的算法。该模型主要用于在线文献的数据提取,具有速... 在分析DOM树的基础上提出一种基于DOM树和递归X-Y分割算法,可以根据网页的几何布局生成Zone树模型。描述了将Zone树模型和递归X-Y算法应用到文献数据检索的优越性,给出构建Zone树模型的算法。该模型主要用于在线文献的数据提取,具有速度快、准确性高等特点,优于目前大多数浏览器所采用的DOM树结构。 展开更多
关键词 HTML文档 DOM树 递归X-Y分割算法 zone
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基于Zone模型的森林小班变化信息提取方法研究 被引量:2
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作者 龚鑫烨 华一枝 +4 位作者 黄星旻 温小荣 林国忠 陶吉兴 徐达 《中南林业科技大学学报》 CAS CSCD 北大核心 2018年第10期34-40,共7页
利用遥感图像监测森林覆盖及其变化是遥感应用的重要领域之一。本研究基于建德市2013和2014年Landsat8 OLI遥感影像数据、森林资源二类调查小班数据及林地落界数据。采用统计分布和Zone模型两种方法提取有林地小班变化信息。评价结果表... 利用遥感图像监测森林覆盖及其变化是遥感应用的重要领域之一。本研究基于建德市2013和2014年Landsat8 OLI遥感影像数据、森林资源二类调查小班数据及林地落界数据。采用统计分布和Zone模型两种方法提取有林地小班变化信息。评价结果表明:基于统计分布法操作简单但效果不够理想;基于Zone模型法检测结果精度高于基于统计分布法,但存在较多伪变化,正确检测率为80.58%,漏检率为19.42%,错检率为84.89%,是一种较好的提取有林地小班变化信息的方法。 展开更多
关键词 小班变化信息 遥感影像 zone模型
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垂向潜流带CO_(2)产量主控因素转变阈值研究
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作者 周诗雨 杨轶群 +3 位作者 戴君一 高迪 李燊琰 王礼春 《地学前缘》 北大核心 2026年第1期25-38,共14页
河流碳排放是全球碳循环的关键环节,潜流带作为其重要组成部分,对碳排放具有显著影响。潜流带CO_(2)产生和排放过程受河流温度和溶解氧(dissolved oxygen,DO)等动态因素控制,然而,目前大多数模型仍基于稳态条件,难以准确捕捉CO_(2)产量... 河流碳排放是全球碳循环的关键环节,潜流带作为其重要组成部分,对碳排放具有显著影响。潜流带CO_(2)产生和排放过程受河流温度和溶解氧(dissolved oxygen,DO)等动态因素控制,然而,目前大多数模型仍基于稳态条件,难以准确捕捉CO_(2)产量动态变化,导致碳排放估算存在较大不确定性。为此,本研究构建了典型沙丘形态的潜流带生物地球化学耦合模型,引入日周期性变化的河流温度和DO,将其作为潜流带边界条件,利用COMSOL Multiphysics对耦合模型进行数值求解,并通过达姆科勒数(Damk hler number,Da)和相关系数来分析河流温度和DO波动边界条件对垂向潜流带CO_(2)产量的动态影响及调控机制。研究结果表明,温度和DO对CO_(2)产生速率具有显著调控作用且存在竞争关系。在潜流带平均滞留时间小于15.7 h时,存在温度阈值,使CO_(2)产生速率的主控因素随河流平均温度发生转换。具体表现为:在温度阈值以下,主控因素为温度波动;而在温度阈值以上,主控因素为DO波动。更为重要的是,当平均滞留时间大于15.7 h时,主控因素转换机制不存在。本研究揭示了河流温度和DO波动对潜流带中CO_(2)产生速率的调控机制,为理解河流碳循环提供了新视角,有助于准确评估潜流带在全球碳循环中的作用,并为预测河流生态系统对气候变化的响应提供理论依据。 展开更多
关键词 潜流带 有氧呼吸 温度阈值 CO_(2) 生物地球化学过程 耦合模型
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水库水位变动影响下消落带沉积物氮磷吸附解吸行为与释放通量估算
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作者 吴默涵 苏小四 +1 位作者 宋铁军 郝源 《地学前缘》 北大核心 2026年第1期14-24,共11页
水库水位变动而形成的消落带作为水陆交错带的关键界面,其沉积物氮磷释放是影响水库水质的重要因素。然而,周期性水位变动引发的消落带氧化还原环境交替变化导致消落带氮磷的释放行为及其对水库水质的影响贡献尚不完全清楚。本研究以吉... 水库水位变动而形成的消落带作为水陆交错带的关键界面,其沉积物氮磷释放是影响水库水质的重要因素。然而,周期性水位变动引发的消落带氧化还原环境交替变化导致消落带氮磷的释放行为及其对水库水质的影响贡献尚不完全清楚。本研究以吉林省某大型水库为研究对象,通过采集淹水前、淹水期和退水期水库地表水和消落带沉积物样品,阐明水位变动下消落带沉积物氮磷释放规律及其对水库水质影响的贡献。研究结果表明:在整个水位波动周期(淹水前—淹水期—退水期),库水氨氮和磷酸根浓度呈现先增加后减小的趋势。沉积物氨氮含量先降低后升高,而无机磷含量则先增加后降低。吸附解吸实验表明酸性条件下(pH=5)沉积物对氨氮和磷酸盐的吸附量较大,而碱性条件(pH=9)下沉积物氮磷解吸作用较强。在退水期,沉积物对氮磷表现出较强的解吸作用。质量平衡法表明,沉积物氮和磷的释放通量分别为324.15 t和8.18 t,其对水库地表水无机氮、磷变化的贡献率分别高达47.22%和57.72%。本项研究对于识别水库内源污染机制,预测水环境风险,保障居民饮水安全和推动水资源可持续管理提供重要科学依据。 展开更多
关键词 水库消落带 水位波动 氮磷含量 释放通量 吸附解吸
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计算辐射换热的Monte-Carlo-Zone方法
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作者 邢华伟 郑楚光 柳朝晖 《燃烧科学与技术》 EI CAS CSCD 1998年第4期379-384,共6页
本文提出了Monte-Carlo方法和Zone方法相结合的一种新的用于辐射传热的计算方法,简称为Monte-Carlo-Zone方法。并用此方法对充满均匀和非均匀吸收辐射灰介质的无限大平板间的辐射换热进行了计算,得出... 本文提出了Monte-Carlo方法和Zone方法相结合的一种新的用于辐射传热的计算方法,简称为Monte-Carlo-Zone方法。并用此方法对充满均匀和非均匀吸收辐射灰介质的无限大平板间的辐射换热进行了计算,得出平板间的无量纲辐射热流及无量纲“跳跃”温度,并与有关文献的分析计算结果进行了比较。 展开更多
关键词 辐射换热 净热流 蒙特卡洛法 温度分布 Z法
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A DISCUSSION ON THE STRUCTURE AND TECTONIC EVOLUTION OF THE ALTUN OROGENIC ZONE 被引量:22
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作者 Liu Liang,Che Zicheng,Luo Jinhai,Wang Yan,Chen Danling 《地学前缘》 EI CAS CSCD 2000年第S1期206-206,共1页
The Altun faulted Zone has been focused by lots of geologists for many years because it lies in a boundary area of several main tectonic units in the western China and is a geographically northern boundary line of Tib... The Altun faulted Zone has been focused by lots of geologists for many years because it lies in a boundary area of several main tectonic units in the western China and is a geographically northern boundary line of Tibet plateau.The latest achievements show that the Altun faulted zone is not only a Cenozoic strike\|slip faulted system but also an orogenic zone which underwent mutually subduction\|collision among paleo\|plates (or terrains) in its early stage and consists of geological bodies of different ages and tectonic environments. Based on the results of geological characteristics,petrology, geochemistry and isotopic dating, the Altun Orogenic Zone can be divided into four tectonic units and is considered to have undergone five stages during its tectonic evolution.The four tectonics units are :(1) Abei metamorphic block, which consists of Archean metamorphic complex of granulite facies;.(2) Hongliugou—Lapeiquan tectonic melange belt, which is composed of ophiolite blocks(belt), OIB blocks, pelagic silicalite, shallow\|bathyal sedimentary rock blocks and high\|pressure metamorphi c rock blocks. (3) Milanhe—Jinyanshan island\|arc block, which consists of mid\|uplifting belt and the south and north active margins. The uplifting belt is composed of metasandstone, marble, overlying thick stromatolite (Jinyanshan Group of Jixian System). Metamorphic rocks of 450Ma occur in both south and north hactive margin. Post\|collision bimodal volcanic rocks and A\|type granite occur in the middle and the north side.(4) Apa—Mangya tectonic melange belt, which consists of ophiolite(including ultramafic rocks, gabbro, plagiogranite and basalt) and flysch and eclogite of late Ordovician. 展开更多
关键词 TECTONIC EVOLUTION Altun OROGENIC zone
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ACCRETION OF AN EARLY CRETACEOUS INTRA- OCEANIC ISLAND ARC TO INDIA: EVIDENCE FROM THE YARLUNG ZANGBO SUTURE ZONE 被引量:2
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作者 J.C.Aitchison 1, Badengzhu 2, A.M.Davis 1, Liu J. 1, Luo, H. 1, J.Malpas 1, I.McDermid 1, Zhou M.F. 1, Wu H. 2, S.Zyabrev 1 《地学前缘》 EI CAS CSCD 2000年第S1期94-96,共3页
A discontinuous line of ophiolitic bodies occurs along the Yarlung Zangbo Suture Zone (YTSZ), which stretches across southern Tibet and beyond. This zone marks the locus of collision between Eurasia and India in the E... A discontinuous line of ophiolitic bodies occurs along the Yarlung Zangbo Suture Zone (YTSZ), which stretches across southern Tibet and beyond. This zone marks the locus of collision between Eurasia and India in the Early Cenozoic. Should we assume that the entire Tethyan Ocean basin that lay between these two continental blocks was oceanic or might it have been more complex? Fragments of any terranes that developed within this once extensive ocean potentially lie within the YTSZ. Detailed investigations over the past three field seasons reveal the presence of several terranes distributed along this zone. Work is currently underway to analyze the nature of individual terranes and the timing of any inter\|relationships. 展开更多
关键词 Yarlung Zangbo SUTURE zone CRETACEOUS island arc OPHIOLITE SUBDUCTION complex
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Fractal Feature of Western Fracture Zone in Xikuangshan Antimony Mine and its Geological Significance 被引量:2
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作者 TANG Shi-jia GAO Guang-ming +1 位作者 PENG En-sheng SUN Zhen-jia 《Journal of Central South University》 SCIE EI CAS 2000年第4期212-215,共4页
In Xikuangshan antimony ore-field, the western fracture zone is a composite of major fault, F75, and its secondary faults, such as F71, F72 and F3 etc.. On plane, the fracture zone scatters from southwest to northeast... In Xikuangshan antimony ore-field, the western fracture zone is a composite of major fault, F75, and its secondary faults, such as F71, F72 and F3 etc.. On plane, the fracture zone scatters from southwest to northeast, and concentrates from upper to deeper level on profile. All ore-bodies exist in the carbonate of footwall of the major fault or that of the footwall of its secondary faults. From 480 m and 320 m to 120 m level, the fractal dimensional number of the fault system decreases from 1.482 2 and 1.448 6 to 1.339 2, which indicates the form of fracture zone becoming more simple at deeper level. And in five sub-ranges, the III and IV sub-ranges are the known area, and the I, II and V sub-ranges are unknown. The fractal studies of the western fracture zone in these sub-ranges show that the fractal dimensional numbers of the I and II, being 1.201 5 and 1.278 0, respectively, are smaller than that of the III and IV, being 1.475 9 and 1.576 9, respectively; and that of the V, being 1.571 2, keeps with that of the III, IV sub-ranges. So mineralization is not well in I and II sub-ranges, and V sub-range is the best to benefit mineralization. 展开更多
关键词 FRACTAL fractal dimension fracture zone Xikuangshan antimony-mine
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Plant Hardiness Zones of China 被引量:1
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作者 Chen YouminDepartment of Landscape Architecture. Beijing Forestry University 《北京林业大学学报》 CAS CSCD 北大核心 1992年第S2期90-92,共3页
China has been divided into eleven plant hardiness zones based on average annunal minimum temperatures.
关键词 HARDINESS zone minimum TEMPERATURE ISOHYET
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