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Evaluation of the Heritage Value Demonstration Degree at the Beijing Tongzhou Grand Canal Heritage Site
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作者 XIAO Yao SUN Shuai +2 位作者 CHEN Yi ZHAO Xinyue CUI Yajia 《Journal of Landscape Research》 2025年第4期39-43,共5页
This study took the Beijing Tongzhou Grand Canal as a case to investigate and evaluate the core section of the Tongzhou Grand Canal.It assessed the historical,artistic,and scientific values embedded in the spatial ent... This study took the Beijing Tongzhou Grand Canal as a case to investigate and evaluate the core section of the Tongzhou Grand Canal.It assessed the historical,artistic,and scientific values embedded in the spatial entity of this cultural heritage and its surrounding environment,as well as the level of its presentation and interpretation.The study culminated in an evaluation of how effectively the heritage values of the Beijing Tongzhou Grand Canal’s spatial heritage are demonstrated.Ultimately,it aimed to provide recommendations and references for the protection and refinement of related cultural heritage spaces,ensuring that the cultural legacy of the Grand Canal’s grain transport system remains enduring and vibrant through time and space. 展开更多
关键词 Tongzhou grand Canal Heritage space Heritage value(s) grand Canal Cultural Belt
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玻利维亚Pastos Grandes盐湖卤水自然蒸发实验研究
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作者 何有芳 余明祥 +2 位作者 秦佳政 李清鸿 王振刚 《盐湖研究》 2025年第1期81-86,共6页
玻利维亚Pastos Grandes(帕斯托斯格兰德斯)盐湖卤水属于典型的氯化物型卤水。文章开展了玻利维亚Pastos Grandes(帕斯托斯格兰德斯)盐湖卤水的自然蒸发实验,获得了此卤水各个蒸发阶段的化学组成变化和析盐顺序,根据析盐顺序可分为5个阶... 玻利维亚Pastos Grandes(帕斯托斯格兰德斯)盐湖卤水属于典型的氯化物型卤水。文章开展了玻利维亚Pastos Grandes(帕斯托斯格兰德斯)盐湖卤水的自然蒸发实验,获得了此卤水各个蒸发阶段的化学组成变化和析盐顺序,根据析盐顺序可分为5个阶段:NaCl析出阶段,NaCl和KCl共析阶段,NaCl、KCl和KCl·MgCl_(2)·6H_(2)O共析阶段,NaCl和KCl·MgCl_(2)·6H_(2)O共析阶段,NaCl、KCl·MgCl_(2)·6H_(2)O和MgCl_(2)·H_(2)O析出共析阶段。结合Na^(+)、K^(+)、Mg^(2+)//Cl^(-)-H_(2)O四元体系25℃相图分析此卤水自然蒸发过程,发现实验蒸发结晶路线与理论结晶路线基本一致,该相图可用于指导Pastos Grandes卤水的自然蒸发。 展开更多
关键词 Pastos grandes盐湖 结晶路线 析盐顺序
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Assessing historical snowfall patterns in Seoul from 1625 to 1907 CE in relation to the Grand Solar Minima
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作者 YuQi Wang Yong Wei +10 位作者 Feng Shi ZhongHua Yao ShiLing Yang Wei Lin LiMei Yan Fei He DaBang Jiang XinAn Yue Kai Fan Si Chen YaoChen Yue 《Earth and Planetary Physics》 2025年第4期904-914,共11页
The Sun is the primary energy source driving the Earth's climate system.A prevailing hypothesis suggests that even minor variations in solar activity,when amplified by climate system feedback mechanisms,can induce... The Sun is the primary energy source driving the Earth's climate system.A prevailing hypothesis suggests that even minor variations in solar activity,when amplified by climate system feedback mechanisms,can induce significant climatic changes on decadal to centennial timescales.However,the limited availability of historical winter climate proxies has impeded consensus on how solar variability influences the long-term winter climate in Northeast Asia,particularly during Grand Solar Minima(GMs).In this study,we analyzed daily-resolution snowfall records in Seoul from 1625 to 1907 CE,derived from the Korean official historical chronicle Seungjeongweon Ilgi.This period encompasses both the Maunder Minimum(1645–1715 CE)and the Dalton Minimum(1790–1830 CE)of solar activity.Our findings indicate that during the GMs,the first date of annual snowfall(FDS)was delayed by approximately 10 days,and the average annual snowfall frequency(ASF)was reduced by half compared to non-GM periods.Additionally,while an 11-year solar cycle was evident in the ASF during non-GM periods,this cycle was replaced by a shortened 8-to 9-year cycle during the GMs.These variations suggest a differential regional climatic response to prolonged changes in solar activity,and provide historical insights that enhance our understanding of the potential impact of low solar activity on the winter climate in Northeast Asia. 展开更多
关键词 historical records grand Solar Minima solar activity regional snowfall
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沉浸在历史的怀抱 Straubinger Grand酒店
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作者 西溪(编译) 《室内设计与装修》 2025年第1期136-141,共6页
当客人步入焕然一新的Straubinger Grand酒店时,首先会感受到这座历史建筑所散发的独特魅力。接待区保留了原始设计的古典氛围,客人领取房卡的天鹅绒抽屉犹如珠宝盒,为入住体验增添了一丝仪式感。直视正前方,宏伟的楼梯通向上层,令人不... 当客人步入焕然一新的Straubinger Grand酒店时,首先会感受到这座历史建筑所散发的独特魅力。接待区保留了原始设计的古典氛围,客人领取房卡的天鹅绒抽屉犹如珠宝盒,为入住体验增添了一丝仪式感。直视正前方,宏伟的楼梯通向上层,令人不禁联想到过去的辉煌时代。餐饮区位于右侧,氛围温馨而典雅,而其旁的咖啡厅连接着Straubinger广场,外设的座位能够容纳12位客人,让他们在户外环境中享用美食,融入广场的日常生活。咖啡厅旁边的酒吧与沙龙提供了一个理想的放松空间,沙龙的窗帘可以根据需要拉上,创造更为私密的环境。 展开更多
关键词 户外环境 grand 原始设计 仪式感 咖啡厅 酒店 日常生活 餐饮区
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Boundedness of the Parametric Littlewood-Paley Operators on Grand Herz-Morrey Spaces with Variable Exponents
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作者 Rui ZHANG Liwei WANG 《Journal of Mathematical Research with Applications》 2025年第5期659-676,共18页
We prove the boundedness of the parametric Lusin's S functionμ_(S)^(?)(f)and Littlewood-Paley's g_(λ)^(*)-funtionμ_(λ),^(*,?)(f)on grand Herz-Morrey spaces with variable exponents.Additionally,we establish... We prove the boundedness of the parametric Lusin's S functionμ_(S)^(?)(f)and Littlewood-Paley's g_(λ)^(*)-funtionμ_(λ),^(*,?)(f)on grand Herz-Morrey spaces with variable exponents.Additionally,we establish the boundedness of higher-order commutators ofμ_(S)^(?)andμ_(λ),^(*,?)with BMO functions applying some properties of variable exponents and generalized BMO norms. 展开更多
关键词 parametric Littlewood-Paley operator COMMUTATOR grand Herz-Morrey space variable exponent
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Identity and Reality: Synchronicity of the Grand Canal Culture and Huai'an Historical and Cultural Space
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作者 Xinting LU Shuyuan LV 《Meteorological and Environmental Research》 2025年第1期70-75,共6页
In order to further explore the rich connotation of Huai'an historical and cultural space and the Grand Canal culture,the synchronicity of urban spatial pattern and historical buildings of Huai'an was studied ... In order to further explore the rich connotation of Huai'an historical and cultural space and the Grand Canal culture,the synchronicity of urban spatial pattern and historical buildings of Huai'an was studied under the guidance of synchronic theory and method.It is found that there are the identity and reality law of the development and change of Huai'an historical and cultural space and the Grand Canal cultural system,and it is deduced that there is a spiraling systematic structure chain between the historical and cultural space of Huai'an and the Grand Canal culture,which provides a theoretical reference for promoting the deepening construction of regional culture,the Grand Canal cultural belt and national cultural parks. 展开更多
关键词 grand Canal culture Historical and cultural space Historic buildings SYNCHRONICITY
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Research on the International Communication Path of Intangible Cultural Heritage Short Videos of the Beijing-Hangzhou Grand Canal
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作者 QI Gang 《Journalism and Mass Communication》 2025年第5期284-290,共7页
As a World Cultural Heritage site,the Beijing-Hangzhou Grand Canal has rich intangible cultural heritage(ICH)along its route.In the era of globalization and media convergence,using short videos to promote the canal’s... As a World Cultural Heritage site,the Beijing-Hangzhou Grand Canal has rich intangible cultural heritage(ICH)along its route.In the era of globalization and media convergence,using short videos to promote the canal’s ICH globally is important for internationalizing Chinese culture.This study uses cross-cultural communication theory,case analysis,and data research to examine the current status of short video dissemination of the canal’s ICH.It identifies core challenges in narrative techniques and cultural translation,and proposes a systematic optimization framework with five dimensions including content and platform.The findings offer both theoretical insights and practical guidance for the international promotion of ICH. 展开更多
关键词 Beijing-Hangzhou grand Canal intangible cultural heritage short video international communication
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JMR Voce Grande书架式音箱
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《视听前线》 2025年第10期70-71,共2页
来自法国的JMR,旗下所有音箱均采用独家“三角传输线”设计,“三角传输线”能够有效抵消箱体内大量驻波,也能保证低频能量不被过分吸收。JMR始终秉持着近乎偏执的匠人精神,尤其钟情于书架箱体的极限探索——在有限的箱体容积内,缔造出... 来自法国的JMR,旗下所有音箱均采用独家“三角传输线”设计,“三角传输线”能够有效抵消箱体内大量驻波,也能保证低频能量不被过分吸收。JMR始终秉持着近乎偏执的匠人精神,尤其钟情于书架箱体的极限探索——在有限的箱体容积内,缔造出媲美落地音箱的声场与低频质感,同时完整保留书架箱特有的空间适配性与音乐精准度,这是一项难度系数极高的技术挑战。Voce Grande就是这种探索精神下的杰作。 展开更多
关键词 书架式音箱 JMR 三角传输线 Voce grande
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大型书架箱的极限探索 JMR Voce Grande书架式音箱
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作者 晨光 《视听前线》 2025年第5期31-35,共5页
如果要问发烧友一个问题:有什么音箱品牌超过50年历史的?相信大家一下子能够数出十个八个,但如果在多加一个条件:有哪些品牌还没被收购、并且坚持在原厂地生产的呢?相信这会难倒不少朋友。然而今天要介绍的这个品牌和产品,成立已经将近6... 如果要问发烧友一个问题:有什么音箱品牌超过50年历史的?相信大家一下子能够数出十个八个,但如果在多加一个条件:有哪些品牌还没被收购、并且坚持在原厂地生产的呢?相信这会难倒不少朋友。然而今天要介绍的这个品牌和产品,成立已经将近60年历史,到现在也是坚持在自家工厂生产,绝不假手于人。 展开更多
关键词 JMR Voce grande 极限探索 书架箱
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The Guardian of the Grand Canal
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作者 REN DEYONG 《China Today》 2025年第8期60-62,共3页
A precious heritage from ancient times,the Beijing-Hangzhou Grand Canal has renewed its former glory through ecological rehabilitation and cultural preservation over the past decades.
关键词 cultural preservation ecological rehabilitation ancient heritage beijing hangzhou grand canal ecological rehabilitation cultural preservation
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Parameterized Littlewood-Paley Operators and Their Commutators on Two-Weight Grand Homogeneous Variable Herz-Morrey Spaces
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作者 Xijuan CHEN Wenwen TAO Guanghui LU 《Journal of Mathematical Research with Applications》 2025年第2期231-242,共12页
In this paper,the authors prove that the parameterized area integralμ_(Ω,S)^(ρ)and the parameterized Littlewood-Paley g_(δ)^(*)-functionμ_(Ω,δ)^(*,ρ)are bounded on two-weight grand homogeneous variable Herz-Mo... In this paper,the authors prove that the parameterized area integralμ_(Ω,S)^(ρ)and the parameterized Littlewood-Paley g_(δ)^(*)-functionμ_(Ω,δ)^(*,ρ)are bounded on two-weight grand homogeneous variable Herz-Morrey spaces MK_(p),θ,q(·))^(α(·),λ)(ω_(1),ω_(2)),where θ>0,λ∈(2,∞),q(·)∈B(R^(n)),α(·)∈L^(∞)(R^(n)),ω_(1)∈A_(p_(ω_(1)))for p_(ω_(1))∈[1,∞]and ω_(2) is a weight.Furthermore,the authors prove that the commutators[b,μ_(Ω,S)^(ρ)]which is formed by b∈BMO(R^(n))and the μ_(Ω,S)^(ρ),and the[b,μ_(Ω,δ)^(*,ρ)]generated by b∈BMO(R^(n))and theμ_(Ω,δ)^(*,ρ)are bounded on MK_(p),θ,q(·))^(α(·),λ)(ω_(1),ω_(2)),respectively. 展开更多
关键词 grand homogeneous variable Herz-Morrey space parameterized area integral parameterized Littlewood-Paley g_(δ)^(*)-function commutator space BMO(R^(n))
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刚果(布)Grande铜矿床地质特征及成矿模式 被引量:3
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作者 肖红 卢树东 +2 位作者 肖淳 刘国荣 晏国龙 《黄金》 CAS 2018年第1期29-33,共5页
刚果(布)Boko Songho矿区Grande铜矿床浅层发育岩溶型氧化矿体,深部发育原生矿体。通过对比分析2类矿体的空间关系及成矿特征的异同性,认为二者的成矿物质具同根同源特征,属于相同成矿作用下在不同层位中就位的上、下2层矿体。长期风化... 刚果(布)Boko Songho矿区Grande铜矿床浅层发育岩溶型氧化矿体,深部发育原生矿体。通过对比分析2类矿体的空间关系及成矿特征的异同性,认为二者的成矿物质具同根同源特征,属于相同成矿作用下在不同层位中就位的上、下2层矿体。长期风化剥蚀使接近地表的上层矿体发生氧化和次生迁移富集形成岩溶型氧化矿体,并因此建立了成矿模式,可为寻找深部原生矿体提供指导。 展开更多
关键词 grande铜矿床 氧化矿体 原生矿体 硫化物型矿石 成矿模式 刚果(布)
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美国新墨西哥洛斯阿拉莫斯Cerro Grande火灾后的紧急溃坝分析 被引量:1
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作者 崔弘毅 《大坝与安全》 2013年第2期63-69,共7页
2005年5月发生的Cerro Grande火灾严重损毁了美国新墨西哥洛斯阿拉莫斯上游的几个森林覆盖流域和洛斯阿拉莫斯国家实验室。火灾彻底改变了这些流域的降雨和径流关系,径流量幅值远大于火灾前的概率增大。径流量大幅加大增加了几座公路堤... 2005年5月发生的Cerro Grande火灾严重损毁了美国新墨西哥洛斯阿拉莫斯上游的几个森林覆盖流域和洛斯阿拉莫斯国家实验室。火灾彻底改变了这些流域的降雨和径流关系,径流量幅值远大于火灾前的概率增大。径流量大幅加大增加了几座公路堤坝和该地区一座大坝发生灾难性溃决失事的可能性。火灾过后,成立了一个跨组织的受灾区域应急抢险小组来评估火灾造成的损失并制定和执行修复计划,以将对生命、财产和自然资源造成的损失降至最低。美国垦务局技术服务中心协助该火灾应急抢险小组进行了溃坝分析和潜在大坝或路堤溃决后风险应对方案的评估。方案评估用时非常短,因为7月1日标志着该地区传统雨季的开始。 展开更多
关键词 Cerro grande火灾 溃决失事 分析评估
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线性分组码的GRAND算法研究
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作者 史治平 杨娟 +1 位作者 李坤阳 王玥 《移动通信》 2024年第5期49-54,共6页
随着5G通信技术的发展与应用,高可靠低时延通信场景下的短包信道编译码技术受到了广泛关注。GRAND是一种通用的最大似然译码算法,与传统译码算法不同,GRAND算法通过噪声猜测和码本查询来确定发送码字,具有高效的硬件实现结构。介绍了GR... 随着5G通信技术的发展与应用,高可靠低时延通信场景下的短包信道编译码技术受到了广泛关注。GRAND是一种通用的最大似然译码算法,与传统译码算法不同,GRAND算法通过噪声猜测和码本查询来确定发送码字,具有高效的硬件实现结构。介绍了GRAND及其改进算法的基本原理,通过仿真分析了不同GRAND算法的误码率性能;针对5G NR的LDPC短码以及PAC短码给出了GRAND算法的设计方案,为未来移动通信的短码设计提供参考。 展开更多
关键词 短码 grand算法 线性分组码
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Rio Grande地堑地壳剪切波速度及径向各向异性
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作者 付媛媛 李爱兵 《国际地震动态》 2015年第9期2-2,共1页
位于新墨西哥和科罗拉多南部的Rio Grande地堑是地球上活动大陆地堑之一,南北长1000多千米。Rio Grande地堑经受过多期活动,形成了多个次级断块。地球化学研究发现玄武岩源区由南部的岩石圈向北过渡到软流圈,表明地堑向北迁移。为探... 位于新墨西哥和科罗拉多南部的Rio Grande地堑是地球上活动大陆地堑之一,南北长1000多千米。Rio Grande地堑经受过多期活动,形成了多个次级断块。地球化学研究发现玄武岩源区由南部的岩石圈向北过渡到软流圈,表明地堑向北迁移。为探讨Rio Grande地堑的形成及演化机制,开展了多种地球物理研究。但以往研究都基于测线,台站稀疏,所得结果精度较低。USArray 密集台站的布设为了解该区精细的地壳结构提供了保证。我们利用USArray台网位于研究区宽频地震台站记录的三分量连续地震噪声数据,获得了Rayleigh和Love波周期为8~35 s的二维相速度。通过联合反演Rayleigh和Love波相速度获取地壳3D剪切波速度及径向各向异性结构,为研究Rio Grande地堑深部地球动力学演化提供地震约束。 展开更多
关键词 grandE 各向异性结构 剪切波速度 地壳结构 RIO 地堑 径向 Rayleigh
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Evaluation of tourism climate comfort in the Grand Shangri-La region 被引量:8
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作者 CHENG Qing-ping ZHONG Fang-lei 《Journal of Mountain Science》 SCIE CSCD 2019年第6期1452-1469,共18页
The Grand Shangri-La(GSL) region has strong international tourist appeal. GSL has considerable international eco-tourist potential as well as being attractive for leisure, vacation, health, explorative, and scientific... The Grand Shangri-La(GSL) region has strong international tourist appeal. GSL has considerable international eco-tourist potential as well as being attractive for leisure, vacation, health, explorative, and scientific research activities in addition to high-end tourism experiences. These factors could promote the development of its regional tourism. GSL has been identified as a key area for tourism development in China. In this study, we investigated tourism climate conditions in GSL from 1980 to 2016 using a tourism climate index(TCI). We found that through global warming, the number of annual and monthly good-weather days, as assessed with the TCI, showed an increase over most of GSL;that trend was especially true for very good, excellent, and ideal days. The optimal travel period was May–October. We obtained the same result using cluster heat maps, in which we categorized 31 studied meteorological stations into eight types. However, heavy rainfall tended to occur during that optimal period, and it was concentrated at certain times. The annual total number of comfortable days greater than 300 was mainly located in southern GSL. We observed significant correlations between monthly and annual excellent and ideal days with latitude and elevation;in particular, we identified a significant nonlinear correlation between excellent(and ideal) days and elevation. 展开更多
关键词 grand Shangri-La REGION EVALUATION TOURISM climate COMFORT Cluster heat MAPS Temperature Precipitation
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Adsorption of Benzene and Propylene in Zeolite ZSM-5:Grand Canonical Monte Carlo Simulations 被引量:9
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作者 SUN Xiao-yan LI Jian-wei +2 位作者 LI Ying-xia YAN Shi-cheng CHEN Biao-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第3期377-382,共6页
The adsorption behavior of benzene and propylene in zeolite ZSM-5 was studied by Grand Canonical Monte Carlo(GCMC) simulations. It could be found that benzene and propylene molecules showed different adsorption beha... The adsorption behavior of benzene and propylene in zeolite ZSM-5 was studied by Grand Canonical Monte Carlo(GCMC) simulations. It could be found that benzene and propylene molecules showed different adsorption behavior in the zeolite cavities. The loadings of propylene were significantly larger than those of benzene at 100 kPa. From the figures of potential energy distribution, the potential energy of benzene/zeolite was more negative than that of propylene/zeolite, so benzene could be adsorbed more stably than propylene. When the temperature was in- creased from 298 to 443 K at 100 kPa, the loading ofpropylene was reduced from 99 to 82 molecules, whereas that of benzene changed little. When benzene and propylene were adsorbed in zeolite simultaneously, the competitive adsorption of them occurred; therefore, the potential energy distribution could be changed significantly. Besides, the adsorption isotherms of benzene and propylene in ZSM-5 at 298 and 443 K were simulated. The results exhibit that the different factors influenced the molecular adsorption at various temperatures and pressures, leading to the diffe- rent rules for the adsorption of benzene and propylene molecules in the zeolite. At a low pressure, the unfavorable energy of propylene/zeolite and the "commensurate freezing" phenomenon of benzene would make the loadings of itself higher than those of propylene. When pressure was higher than 5 kPa, the adsorption of benzene in ZSM-5 would nearly reach saturation. 展开更多
关键词 ZSM-5 zeolite ADSORPTION grand canonical monte carlo
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Diffusion and Adsorption of Benzene and Propylene in MFI,MWW and BEA Zeolites:Molecular Dynamics and Grand Canonical Monte Carlo Simulations 被引量:4
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作者 SUN Xiao-yan JIAO Wei +1 位作者 XIANG Shu-guang LI Jlan-wei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第2期318-323,共6页
The diffusion and adsorption behaviors of benzene and propylene in zeolites MFI, MWW and BEA have been studied by molecular dynamics(MD) and grand canonical Monte Carlo(GCMC) simulations. The diffusion coefficient... The diffusion and adsorption behaviors of benzene and propylene in zeolites MFI, MWW and BEA have been studied by molecular dynamics(MD) and grand canonical Monte Carlo(GCMC) simulations. The diffusion coefficients of benzene and propylene in MFI, MWW and BEA zeolites were calculated by simulating the mean-square displacements(MSD) at 298 and 600 K. Benzene and propylene showed the different adsorption rules in the channels of the three zeolites. For propylene, the molecular loadings decreased in the order: BEA(linear channel)〉BEA (tortuous channel)〉MFI(linear channel)〉MWW(12-membered rings, 12MR channel)〉MFI(tortuous channel)〉MWW (10-membered rings, 10MR channel); for benzene, the molecular loadings decreased in the order: BEA(linear chan-nel)〉BEA(tortuous channel)〉MWW(12MR channel)〉MFI(linear channel)〉MFI(tortuous channel)〉MWW(10MR channel). Besides, the adsorption isotherms of benzene and propylene in the three zeolites at 298 and 443 K were simulated. The results show that the different factors influenced the molecular adsorption at various temperatures and pressures, leading to the different rules for the adsorption of benzene and propylene molecules in the zeolites. At a low pressure, the unfavorable energy would make the loadings of propylene lower than those of benzene. When pressure was higher than 0.25 kPa, the adsorption of benzene in MFI would nearly reach saturation. 展开更多
关键词 Zeolite Molecular dynamics DIFFUSION ADSORPTION grand canonical Monte Carlo
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Pollution characteristics of the recent sediments in the Hangzhou section of the Grand Canal,China 被引量:3
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作者 CHENYing-xu LIUHe +2 位作者 ZHUGuang-wei CHENHua-lin TIANGuang-min 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第1期34-39,共6页
Spatial distribution of heavy metals, arsenic and organic matter in recent sediments in the Hangzhou section of the Grand Canal and their relationships were analyzed. The results showed that the concentrations of heav... Spatial distribution of heavy metals, arsenic and organic matter in recent sediments in the Hangzhou section of the Grand Canal and their relationships were analyzed. The results showed that the concentrations of heavy metals and organic matters varied widely along the canal, and the average geological accumulation factors decreased in the following orders: organic carbon(2.6), zinc(2.1), cadmium(2.0), copper(1.5), lead(1.1), nitrogen(0.9), mercury (0.8), phosphorus(0.4), arsenic(0.2) and chromium(0). Content of heavy metals and organic carbon in the top 10 cm layer were lower than that of lower layers, except for mercury and organic carbon in the S9 section. Contents of organic carbon in the top 50 cm layer of the mud sediments are significantly higher than those underneath. In the bottom mud layer, there is a concentration peak of the pollutants. In the mud sediments of the canal, cadmium mainly occurred in the Fe and Mn oxide fraction, copper in the organic fraction, lead in the Fe and Mn oxide fraction, and zinc in the carbonate and the Fe and Mn oxide fraction. 展开更多
关键词 SEDIMENT pollution characteristics grand Canal geological accumulation factor fraction of heavy metals
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Sorption and permeation of gaseous molecules in amorphous and crystalline PPX C membranes: molecular dynamics and grand canonical Monte Carlo simulation studies 被引量:2
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作者 边亮 舒远杰 王新峰 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期325-336,共12页
Amorphous and crystalline poly (chloro-p-xytylene) (PPX C) membranes are constructed by using a novel com- putational technique, that is, a combined method of NVT+NPT-molecular dynamics (MD) and gradually reduc... Amorphous and crystalline poly (chloro-p-xytylene) (PPX C) membranes are constructed by using a novel com- putational technique, that is, a combined method of NVT+NPT-molecular dynamics (MD) and gradually reducing the size (GRS) methods. The related free volumes are defined as homology clusters. Then the sorption and the permeation of gases in PPX C polymers are studied using grand canonical Monte Carlo (GCMC) and NVT-MD methods. The results show that the crystalline PPX C membranes provide smaller free volumes for absorbing or transferring gases relative to the amorphous PPX C area. The gas sorption in PPX C membranes mainly belongs to the physical one, and H bonds can appear obviously in the amorphous area. By cluster analyzing on the mean square displacement of gases, we find that gases walk along the x axis in the crystalline area and walk randomly in the amorphous area. The calculated permeability coefficients are close to the experimental data. 展开更多
关键词 cluster analysis parylene C grand canonical Monte Carlo method molecular dynamics
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