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Multidimensional data-driven porous media reconstruction:Inversion from 1D/2D pore parameters to 3D real pores
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作者 Peng Chi Jian-Meng Sun +5 位作者 Ran Zhang Wei-Chao Yan Huai-Min Dong Li-Kai Cui Rui-Kang Cui Xin Luo 《Petroleum Science》 2025年第7期2777-2793,共17页
Subsurface rocks,as complex porous media,exhibit multiscale pore structures and intricate physical properties.Digital rock physics technology has become increasingly influential in the study of subsurface rock propert... Subsurface rocks,as complex porous media,exhibit multiscale pore structures and intricate physical properties.Digital rock physics technology has become increasingly influential in the study of subsurface rock properties.Given the multiscale characteristics of rock pore structures,direct three-dimensional imaging at sub-micrometer and nanometer scales is typically infeasible.This study introduces a method for reconstructing porous media using multidimensional data,which combines one-dimensional pore structure parameters with two-dimensional images to reconstruct three-dimensional models.The pore network model(PNM)is stochastically reconstructed using one-dimensional parameters,and a generative adversarial network(GAN)is utilized to equip the PNM with pore morphologies derived from two-dimensional images.The digital rocks generated by this method possess excellent controllability.Using Berea sandstone and Grosmont carbonate samples,we performed digital rock reconstructions based on PNM extracted by the maximum ball algorithm and compared them with stochastically reconstructed PNM.Pore structure parameters,permeability,and formation factors were calculated.The results show that the generated samples exhibit good consistency with real samples in terms of pore morphology,pore structure,and physical properties.Furthermore,our method effectively supplements the micropores not captured in CT images,demonstrating its potential in multiscale carbonate samples.Thus,the proposed reconstruction method is promising for advancing porous media property research. 展开更多
关键词 3d digital rock Pore network model 1d/2d pore parameters Pore structure Generative adversarial network
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Z型异质结1D/2D g-C_(3)N_(5)/g-C_(3)N_(4)的构建及可见光催化降解甲基橙 被引量:7
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作者 卜义夫 刘思乐 +3 位作者 闫海生 吴静 田川 陶洋 《材料工程》 EI CAS CSCD 北大核心 2024年第10期170-182,共13页
以三聚氰胺和3-氨基-1,2,4-三唑为原料,通过直接热聚合法制备1D/2D g-C_(3)N_(5)/g-C_(3)N_(4)异质结光催化材料。通过XRD,XPS,SEM等表征手段对光催化材料的晶型、化学组成、形貌以及光电化学性质等进行表征。以甲基橙(MO)为目标污染物,... 以三聚氰胺和3-氨基-1,2,4-三唑为原料,通过直接热聚合法制备1D/2D g-C_(3)N_(5)/g-C_(3)N_(4)异质结光催化材料。通过XRD,XPS,SEM等表征手段对光催化材料的晶型、化学组成、形貌以及光电化学性质等进行表征。以甲基橙(MO)为目标污染物,500 W氙灯作为可见光光源,研究1D/2D g-C_(3)N_(5)/g-C_(3)N_(4)异质结光催化材料的光催化活性,同时通过活性物质捕捉实验和电子顺磁共振波谱(e1ectron spin resonance,ESR)表征研究体系的活性物质。结果表明:一维g-C_(3)N_(5)纳米棒和二维g-C_(3)N_(4)纳米片的无序堆叠增加了活性位点的数量,g-C_(3)N_(5)与g-C_(3)N_(4)之间Z型异质结的形成,提高其对可见光的吸收强度和光谱范围,抑制了光电子-空穴的复合,g-C_(3)N_(5)与g-C_(3)N_(4)相似的π-π^(*)共轭体系的相互叠加降低了电荷转移的传质阻力,提高了其光催化活性。可见光照射30 min,20 mg的1D/2D g-C_(3)N_(5)/g-C_(3)N_(4)光催化材料对50 mL浓度为10 mg/L的MO溶液几乎降解完全,反应的表观速率常数为0.14836 min^(-1),循环使用5次后,1D/2D g-C_(3)N_(5)/g-C_(3)N_(4)光催化材料对MO的光催化降解率为92.2%,这说明其具有良好的稳定性。活性物质捕捉实验和ESR表征表明:1D/2D g-C_(2)N_(5)/g-C_(3)N_(4)光催化材料光催化降解MO体系的主要活性物质是·O_(2)^(-)和h^(+),且MO的光催化降解反应是一个复杂的断键和氧化过程。 展开更多
关键词 光催化降解 直接热聚合 1d/2d g-C_(3)N_(5)/g-C_(3)N_(4) 异质结 π-π^(*)共轭 甲基橙 Z型机制
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Superior Mechanical Behavior and Flame Retardancy FRP via a Distribution Controllable 1D/2D Hybrid Nanoclay Synergistic Toughening Strategy
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作者 Zixuan Chen Tianyu Yu +4 位作者 Zetian Yang Zhibiao Wei Yan Li Weidong Yang Tao Yu 《Engineering》 SCIE EI CAS CSCD 2024年第9期166-178,共13页
The incorporation of commercial flame retardants into fiber-reinforced polymer(FRP)composites has been proposed as a potential solution to improve the latter’s poor flame resistance.However,this approach often poses ... The incorporation of commercial flame retardants into fiber-reinforced polymer(FRP)composites has been proposed as a potential solution to improve the latter’s poor flame resistance.However,this approach often poses a challenge,as it can adversely affect the mechanical properties of the FRP.Thus,balancing the need for improved flame resistance with the preservation of mechanical integrity remains a complex issue in FRP research.Addressing this critical concern,this study introduces a novel additive system featuring a combination of one-dimensional(1D)hollow tubular structured halloysite nanotubes(HNTs)and two-dimensional(2D)polygonal flake-shaped nano kaolinite(NKN).By employing a 1D/2D hybrid kaolinite nanoclay system,this research aims to simultaneously improve the flame retardancy and mechanical properties.This innovative approach offers several advantages.During combustion and pyrolysis processes,the 1D/2D hybrid kaolinite nanoclay system proves effective in reducing heat release and volatile leaching.Furthermore,the system facilitates the formation of reinforcing skeletons through a crosslinking mechanism during pyrolysis,resulting in the development of a compact char layer.This char layer acts as a protective barrier,enhancing the material’s resistance to heat and flames.In terms of mechanical properties,the multilayered polygonal flake-shaped 2D NKN plays a crucial role by impeding the formation of cracks that typically arise from vulnerable areas,such as adhesive phase particles.Simultaneously,the 1D HNT bridges these cracks within the matrix,ensuring the structural integrity of the composite material.In an optimal scenario,the homogeneously distributed 1D/2D hybrid kaolinite nanoclays exhibit remarkable results,with a 51.0%improvement in mode II fracture toughness(GIIC),indicating increased resistance to crack propagation.In addition,there is a 34.5%reduction in total heat release,signifying improved flame retardancy.This study represents a significant step forward in the field of composite materials.The innovative use of hybrid low-dimensional nanomaterials offers a promising avenue for the development of multifunctional composites.By carefully designing and incorporating these nanoclays,researchers can potentially create a new generation of FRP composites that excel in both flame resistance and mechanical strength. 展开更多
关键词 1d/2d nanoclays Hierarchical distribution Flame retardancy Fiber-reinforced polymer damage mechanism
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1D/2D TiO_(2)/ZnIn_(2)S_(4) S-scheme heterojunction photocatalyst for efficient hydrogen evolution 被引量:14
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作者 Jinmao Li Congcong Wu +3 位作者 Jin Li Binghai Dong Li Zhao Shimin Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第2期339-349,共11页
TiO_(2)is a promising photocatalyst with limited use in practical applications owing to its wide bandgap,narrow light response range,and rapid recombination of photoexcited carriers.To address these limitations,a nove... TiO_(2)is a promising photocatalyst with limited use in practical applications owing to its wide bandgap,narrow light response range,and rapid recombination of photoexcited carriers.To address these limitations,a novel 1D/2D TiO_(2)/ZnIn_(2)S_(4)heterostructure was designed according to the principles of the S-scheme heterojunction.The TiO_(2)/ZnIn_(2)S_(4)(TZISx)hybrids prepared via a hydrothermal method afforded significant improvement in photocatalytic hydrogen evolution(PHE)in comparison to pristine TiO_(2)and ZnIn_(2)S_(4).In particular,the optimal TZIS2 sample(mass ratio of ZnIn_(2)S_(4)to TiO_(2)was 0.4)exhibited the highest PHE activity(6.03 mmol/h/g),which was approximately 3.7 and 2.0 times higher than those of pristine TiO_(2)and ZnIn_(2)S_(4),respectively.This improvement in the PHE of the TZIS2 sample could be attributed to the formation of an intimate heterojunction interface,high-efficiency separation of charge carriers,abundant reactive sites,and enhanced light absorption capacity.Notably,theoretical and experimental results demonstrated that the S-scheme mechanism of interfacial electron transfer in the TZISx composites facilitated the transfer and separation of photoexcited charge carriers,resulting in more isolated photoexcited electrons for the PHE reaction. 展开更多
关键词 S-scheme heterojunction TiO_(2) ZnIn_(2)S_(4) 1d/2d Photocatalytic hydrogen evolution
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HYDRUS-1D/2D在土壤水分入渗过程模拟中的应用 被引量:29
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作者 汤英 徐利岗 +1 位作者 张红玲 鲍子云 《安徽农业科学》 CAS 北大核心 2011年第36期22390-22393,共4页
介绍了HYDRUS-1D/2D软件的特点及其组成,并以古尔班通古特沙漠融雪水入渗过程为例,基于各项土壤物理特征参数,应用该软件模拟了沙漠垄间及垄顶距树干不同距离处的土壤含水量随入渗时间的变化过程,并以实测数据进行验证,模拟效果良好。... 介绍了HYDRUS-1D/2D软件的特点及其组成,并以古尔班通古特沙漠融雪水入渗过程为例,基于各项土壤物理特征参数,应用该软件模拟了沙漠垄间及垄顶距树干不同距离处的土壤含水量随入渗时间的变化过程,并以实测数据进行验证,模拟效果良好。总结了模型应用步骤、该软件的优点。 展开更多
关键词 HYdRUS-1d/2d 入渗模拟 融雪水 土壤水含量 古尔班通古特沙漠
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1D/2D无机/有机异质结的构筑对可见光催化分解水产氢性能影响的综合实验设计 被引量:1
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作者 董贝贝 郭海威 黄小园 《实验科学与技术》 2023年第1期66-71,共6页
为使学生深入了解光催化等热点研究领域的学术前沿,掌握低维纳米复合材料的制备方法,设计了1D/2D无机/有机异质结的构筑对可见光催化分解水产氢性能影响的本科生综合实验。采用简单的混合煅烧法制备了1D纳米棒和2D纳米片异质结,该异质... 为使学生深入了解光催化等热点研究领域的学术前沿,掌握低维纳米复合材料的制备方法,设计了1D/2D无机/有机异质结的构筑对可见光催化分解水产氢性能影响的本科生综合实验。采用简单的混合煅烧法制备了1D纳米棒和2D纳米片异质结,该异质结的致密界面显著促进了光生电荷分离,最终使其光催化分解水产氢速率大幅度提高。该实验设计的综合性较强,基础知识与实验结果紧密结合,有利于激发学生的创新思维,培养学生的综合实验素养。 展开更多
关键词 综合实验设计 光催化制氢 可见光响应 电荷分离 1d/2d异质结
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Fine-scale damage assessment of urban flooding based on the 1D/2D coupled hydrodynamic model 被引量:1
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作者 Boliang Dong Junqiang Xia +1 位作者 Qijie Li Xiaojie Wang 《River》 2023年第4期403-420,共18页
Due to the high population density and economic property in urban environments,urban flooding can result in substantial economic losses.However,accurate urban flood modeling and assessing the associated damages are ch... Due to the high population density and economic property in urban environments,urban flooding can result in substantial economic losses.However,accurate urban flood modeling and assessing the associated damages are challenging due to complex urban layouts and rugged topography.Furthermore,the rapid development of urban underground spaces has introduced additional complexities.To address the demanding need for accurate flood modeling and damage assessment in cities,a fine-scale flood damage assessment method was proposed in this study,based on the 1D/2D coupled hydrodynamic model,which can not only assess the flood damage on the ground surface but also evaluate the flood loss in underground spaces.Taking the Gangxi drainage area in Wuhan City,China as a case,this study extensively discussed the flood inundation processes on the ground surface as well as in the buildings and underground spaces,under different rainfall scenarios with the return period ranging from 2 to 200 years.Based on the high spatial-temporal hydrodynamic simulations,the flood damage degrees were evaluated for the buildings and underground spaces with different industry types.The results indicated that the inundation of buildings and underground spaces in densely built cities cannot be neglected in urban flood modeling.Buildings with public service attributes can have a higher flood damage degree,as compared with other types of buildings and underground spaces. 展开更多
关键词 1d/2d coupled modeling flood damage assessment underground spaces urban flooding
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基于OCDM混合1D/2D码的PON监控系统分析
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作者 仝国利 李跃辉 +1 位作者 李茂文 张功 《光通信技术》 CSCD 北大核心 2013年第4期33-34,共2页
主要讨论基于OCDM混合1D/2D码在PON监控系统中的使用及整体模型,该模型是在1D码、2D码基础上提出的,是1D码和2D码的结合体。利用混合1D/2D码技术对不同的用户分配不同的码字,以实现多用户、高信噪比的实时监控。
关键词 无源光网络 混合1d 2d 光码分复用 光时域反射仪
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An Implicit Coupled 1D/2D Model for Unsteady Subcritical Flow in Channel Networks and Embayment
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作者 GENG Yan-fen WANG Zhi-li 《China Ocean Engineering》 SCIE EI CSCD 2020年第1期110-118,共9页
In this study, 1D and 2D shallow-water models were coupled to simulate unsteady flow in channel networks and embayment. The 1D model solved the 1D shallow-water equations (St. Venant) using the Preissmann box method a... In this study, 1D and 2D shallow-water models were coupled to simulate unsteady flow in channel networks and embayment. The 1D model solved the 1D shallow-water equations (St. Venant) using the Preissmann box method and targeted long narrow reaches of the river networks, while the 2D model targeted broad channels and embayment and solved the 2D shallow-water equations using a semi-implicit scheme applied to an unstructured grid of triangular cells. The 1D and 2D models were solved simultaneously by building a matrix for the free surface elevation at every 1D junction and 2D cell center. Velocities were then computed explicitly based on the results at the previous time step and the updated water level. The originality of the scheme arose from a novel coupling method. The results showed that the coupled 1D/2D model produced identical results as the full 2D model in classical to benchmark problems with considerable savings in computational effort. Application of the model to the Pearl River Estuary in southern China showed that complex patterns of tidal wave propagation could be efficiently modeled. 展开更多
关键词 1d river network model 2d unstructured model full coupling model Pearl River delta
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A deterministic distributed modeling approach of Mediterranean water-cycle assessment,application in the Var catchment,France
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作者 Siyuan Chang Zhengmiao Li +2 位作者 Xinyi Lian Philippe Gourbesville Qiang Ma 《River》 2025年第3期297-310,共14页
Characterized by special morphologic,geographic,hydrologic,and societal behaviors,the water resources management of the Mediterranean catchment often shows a higher level of complexity including security issues of wat... Characterized by special morphologic,geographic,hydrologic,and societal behaviors,the water resources management of the Mediterranean catchment often shows a higher level of complexity including security issues of water supply,inundation risks,and environment management under the perspective of climate change.To have a comprehensive understanding of the Mediterranean water-cycle system,a deterministic distributed hydrologic modeling approach has been developed and presented in this study based on an application in the Var catchment(2800 km^(2))located at the French Mediterranean region.A 1D and 2D coupled model of MIKE SHE and MIKE 11 has been set up under a series of hypotheses to represent the whole hydrologic and hydrodynamic processes including rainfall-runoff,snow-melting,channel flow,overland flow,and the water exchange between land surface and unsaturated/saturated zones.The developed model was first calibrated with 4 years daily records from 2008 to 2011,then to be validated and further run within hourly time interval to produce detailed representation of the catchment water-cycle from 2012 to 2014.The deterministic distributed modeling approach presented in this study is able to represent its complicated water-cycle and used for supporting the decision‐making process of the water resources management of the catchment. 展开更多
关键词 1d/2d coupled model distributed hydrological model flood management Mediterranean catchment
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2D/1D耦合的堆芯实测功率分布快速重构研究 被引量:3
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作者 龚禾林 李庆 +11 位作者 刘启伟 李向阳 卢宗健 王金雨 谢运利 陈长 于颖锐 彭星杰 刘琨 郭锐 张斌 王星博 《原子能科学技术》 EI CAS CSCD 北大核心 2021年第2期272-278,共7页
针对三代核电压水堆在线监测系统需要快速准确进行实测3D功率重构的需求,本文提出了一种2D/1D耦合的3D功率重构方法。首先采用耦合系数法对探测器层的功率进行了2D实测功率重构;其次针对每个组件,采用二次样条函数拟合方法进行了轴向1D... 针对三代核电压水堆在线监测系统需要快速准确进行实测3D功率重构的需求,本文提出了一种2D/1D耦合的3D功率重构方法。首先采用耦合系数法对探测器层的功率进行了2D实测功率重构;其次针对每个组件,采用二次样条函数拟合方法进行了轴向1D实测功率重构,最后得到了全堆3D实测功率分布。该方法计算流程简单,占用内存少。针对华龙一号开展的4个典型例题的数值验证结果表明,该方法具备很高的精度,满足三代核电在线监测系统实测功率重构对精度和速度的要求。 展开更多
关键词 功率重构 耦合系数法 二次样条函数拟合法 华龙一号 2d/1d
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基于大规模并行计算的2D/1D耦合三维全堆输运程序Tiger-3D 被引量:2
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作者 吴文斌 李庆 王侃 《核动力工程》 EI CAS CSCD 北大核心 2014年第S2期135-139,共5页
2D/1D耦合方法求解三维输运方程具有快速、精确的优点;通常的2D/1D耦合方法利用轴向和角度方面的并行度,不能进行大规模并行计算。本研究在三维粗网有限差分(CMFD)框架下,径向采用区域分解并行的矩阵特征线方法(MOC),轴向采用扩散有限差... 2D/1D耦合方法求解三维输运方程具有快速、精确的优点;通常的2D/1D耦合方法利用轴向和角度方面的并行度,不能进行大规模并行计算。本研究在三维粗网有限差分(CMFD)框架下,径向采用区域分解并行的矩阵特征线方法(MOC),轴向采用扩散有限差分,综合利用2D/1D耦合方法径向和轴向的并行度,基于消息传递接口(MPI)实现大规模的并行计算,编写了Tiger-3D程序。数值验证表明,Tiger-3D程序具有良好的计算精度和较高的计算效率。 展开更多
关键词 2d/1d耦合方法 全堆输运计算 大规模并行计算
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1D Mn_(0.2)Cd_(0.8)S纳米棒/2D Ti_3C_(2)纳米片肖特基异质结的构建及光催化产氢性能研究 被引量:23
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作者 姜志民 陈晴 +3 位作者 郑巧清 沈荣晨 张鹏 李鑫 《物理化学学报》 SCIE CAS CSCD 北大核心 2021年第6期180-190,共11页
开发低成本的半导体光催化剂以实现可见光下高效、持久的光催化分解水产氢化是一个非常具有挑战性的课题。近年来,1D Mn_xCd_(1-x)S纳米结构由于载流子扩散路径短,长径比高,具有优异的光吸收、电荷分离和H_(2)析出活性,而广泛地应用在... 开发低成本的半导体光催化剂以实现可见光下高效、持久的光催化分解水产氢化是一个非常具有挑战性的课题。近年来,1D Mn_xCd_(1-x)S纳米结构由于载流子扩散路径短,长径比高,具有优异的光吸收、电荷分离和H_(2)析出活性,而广泛地应用在光催化H_(2)析出应用中。然而,单一的Mn_xCd_(1-x)S光催化剂仍然存在着一些缺点,如光生电子-空穴对的快速复合和量子效率低等。为了进一步促进光生电荷载流子的分离和H_(2)释放动力学,采用原位溶剂热法合成了Mn_(0.2)Cd_(0.8)S纳米棒(MCSNRs)和Ti_3C_(2)MXene纳米片(NSs)之间的1D/2D肖特基异质结。采用各种表征方法深入地研究了金属Ti_3C_(2)MXene NSs在Mn_(0.2)Cd_(0.8)S纳米棒上促进光催化H_(2)进化的关键作用和潜在机制。通过X射线衍射(XRD)、透射电子显微镜(TEM)、高分辨透射电镜(HRTEM)、元素分布图和X射线光电子能谱(XPS)等测试手段,证实成功地构建了低成本的肖特基杂质结,并将其应用于光催化产氢反应中。此外,在Na_(2)SO_3和Na_(2)S混合牺牲剂溶液中,进行了光催化析氢反应。优化后的1D/2D肖特基异质结的最高析氢速率为15.73 mmol·g^(-1)·h^(-1),比纯MCS NRs(2.34 mmol·g^(-1)·h^(-1))高6.72倍。在420nm处获得了19.6%的表观量子效率(AQE)。稳定性测试结果表明,二元光催化剂具有良好的光催化稳性性及广阔的应用前景。更有趣的是,紫外-可见漫反射光谱、光致发光(PL)光谱、瞬态光电流响应和极化曲线谱都清楚地证实了MCS NRs和Ti_3C_(2)MXene纳米片之间的有效电荷分离。线性扫描伏安法(LSV)也表明,MXene助催化剂的加入可以显著降低纯MCS NRs的过电位,证实2D Ti_3C_(2)NSs可以作为电子导电桥梁,改善H_(2)析出动力学。总之,金属Ti_3C_(2)MXene NSs和MCS NRs之间的2D/1D杂化肖特基异质结不仅可以大大改善光生电子和空穴的分离,而且可以减少H_(2)析出过电位,从而显著提高光催化产氢活性。希望本文的研究能为低成本肖特基异质结的构建提供新的思路,为光催化H_(2)生产的实际应用提供参考。 展开更多
关键词 光催化产氢 1d Mn_(0.2)Cd_(0.8)S纳米棒 Ti_3C_(2)Mxene纳米片 2d/1d肖特结 太阳燃料
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基于2D/1D输运程序KYCORE的敏感性分析 被引量:1
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作者 吴屈 彭星杰 +4 位作者 唐霄 施冠麟 于颖锐 李庆 王侃 《核动力工程》 EI CAS CSCD 北大核心 2018年第S2期15-19,共5页
本研究基于2D/1D输运程序KYCORE开发了共轭敏感性分析(ASA)和基于减秩模型(ROM)的前向敏感性分析(FSA)功能,并在TMI-1压水堆栅元基准题进行了验证。结果表明,KYCORE与RMC计算的有效增殖因子(keff)对235U每个能群的裂变截面和俘获截面的... 本研究基于2D/1D输运程序KYCORE开发了共轭敏感性分析(ASA)和基于减秩模型(ROM)的前向敏感性分析(FSA)功能,并在TMI-1压水堆栅元基准题进行了验证。结果表明,KYCORE与RMC计算的有效增殖因子(keff)对235U每个能群的裂变截面和俘获截面的敏感性系数符合良好,但在共振能量附近,两者有些差异;基于ROM的fsa方法计算得到的敏感性系数与直接扰动法(DNP)计算得到的敏感性系数一致。因此,本研究所开发的基于2D/1D输运程序KYCORE ASA和基于rom的FSA功能正确。 展开更多
关键词 共轭敏感性分析(ASA) 减秩模型(ROM) 向前敏感性分析(FSA) 2d/1d输运
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基于卷积注意力机制的2D-LiDAR实时人体检测算法
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作者 刘鹏华 郑宝志 +1 位作者 姚瀚晨 戴厚德 《传感器与微系统》 CSCD 北大核心 2024年第2期153-156,164,共5页
针对激光雷达(LiDAR)数据稀疏且信息含量低,难以识别人体特征的难题,提出一种基于卷积注意力机制的人体腿部实时检测方法。通过深度引导的滑动窗口对激光点信息预处理,使对象在不同的距离上有相同的特征信息。通过时间信息聚合,获得LiDA... 针对激光雷达(LiDAR)数据稀疏且信息含量低,难以识别人体特征的难题,提出一种基于卷积注意力机制的人体腿部实时检测方法。通过深度引导的滑动窗口对激光点信息预处理,使对象在不同的距离上有相同的特征信息。通过时间信息聚合,获得LiDAR数据更丰富的空间表现,减少运算时间。通过卷积注意力模块与自回归模型卷积神经网络,对空间邻域关联错位的特征进行分析。为验证本文提出算法对行人腿部的检测效果,在DROW验证集的3种评估半径下,曲线下面积(AUC)提高21%以上,F1提高14%以上,检测时间平均降低13 ms。实验结果表明:本文算法相比于DROW算法具有更高的检测精度与更快的运算速度。 展开更多
关键词 一维卷积神经网络 注意力机制 二维激光雷达 人体腿部识别
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微波辅助快速制备2D/1D ZnIn_(2)S_(4)/TiO_(2) S型异质结及其光催化制氢性能 被引量:24
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作者 梅子慧 王国宏 +1 位作者 严素定 王娟 《物理化学学报》 SCIE CAS CSCD 北大核心 2021年第6期137-147,共11页
能源危机的威胁在过去二十年里引起了全球性广泛关注。由于地球上具有丰富的太阳能和水资源,光催化分解水制氢被认为是获取绿色能源的一种有效途径。迄今为止,许多光催化剂已经得到了深入研究。其中,TiO_(2)以其无毒、化学稳定性高、形... 能源危机的威胁在过去二十年里引起了全球性广泛关注。由于地球上具有丰富的太阳能和水资源,光催化分解水制氢被认为是获取绿色能源的一种有效途径。迄今为止,许多光催化剂已经得到了深入研究。其中,TiO_(2)以其无毒、化学稳定性高、形态可控、光催化活性强等优点得到了广泛的关注。特别是1D结构的TiO_(2)纳米纤维具有独特的一维电子转移轨迹,较大的吸附能力和较高的光生电子-空穴对(e~--h~+)传输速率等优点在光催化领域更是受到研究人员的青睐。尽管如此,TiO_(2)仍存在带隙大、光生电子-空穴对复合速率快等缺点,使其在制氢反应(HER)中效率不高。因此,构建高性能、经济、环保的光催化剂是实现太阳能高效转化的一大挑战。最近,各种提高TiO_(2)光催化活性的策略得到了广泛研究,包括与窄带隙半导体(如ZnIn_(2)S_(4))的耦合等。另外,微波辅助合成技术以其成本低、设备简单、环境无污染、反应速度快等优点,已成为制备光催化半导体材料的一种重要手段。在本工作中,为解决TiO_(2)带隙宽(约3.2 e V)和电子-空穴对复合速率快等缺点,通过微波辅助合成技术快速地将2D结构的ZnIn_(2)S_(4)纳米片原位组装在TiO_(2)纳米纤维上,构筑2D/1D ZnIn_(2)S_(4)/TiO_(2)S型异质结。通过调节ZnIn_(2)S_(4)前驱体与TiO_(2)NFs的摩尔比,可以很容易地控制TiO_(2)纳米纤维上ZnIn_(2)S_(4)负载量。实验结果表明:相对于纯ZnIn_(2)S_(4)和TiO_(2)而言,ZnIn_(2)S_(4)/TiO_(2)异质结光催化剂在太阳光照射下的光吸收和制氢性能得到明显提高。在优化条件下,样品ZT-0.5 (ZnIn_(2)S_(4)与TiO_(2)的摩尔比为0.5)具有最佳制氢性能,达到8774mmol·g^(-1)·h^(-1),分别是纯TiO_(2)纳米纤维(3312mmol·g^(-1)·h^(-1))和ZnIn_(2)S_(4) (3114mmol·g^(-1)·h^(-1))纳米片的2.7倍和2.8倍。基于实验结果,我们提出来一种在ZnIn_(2)S_(4)和TiO_(2)间形成的S型异质结机理,并很好地阐释了ZnIn_(2)S_(4)/TiO_(2)复合材料光催化制氢活性增强的原因。 展开更多
关键词 微波辅助法 2d/1d ZnIn_(2)S_(4)/TiO_(2) S型异质结 光催化制氢
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基于广义等价理论CMFD加速的2D MOC/1D S_(N)算法的收敛性改进研究
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作者 孔勃然 朱凯杰 +3 位作者 张汉 郝琛 郭炯 李富 《核动力工程》 EI CAS CSCD 北大核心 2023年第3期45-53,共9页
基于广义等价理论的CMFD(GET-CMFD)方法具有较好的收敛性,并成功应用到基于轴向节块展开法(NEM)的2D/1D算法中。然而,当采用具有更高精度的离散纵标法(S_(N))作为轴向求解器时,2D/1D算法面临不收敛的问题。为了解决此问题,本文针对采用... 基于广义等价理论的CMFD(GET-CMFD)方法具有较好的收敛性,并成功应用到基于轴向节块展开法(NEM)的2D/1D算法中。然而,当采用具有更高精度的离散纵标法(S_(N))作为轴向求解器时,2D/1D算法面临不收敛的问题。为了解决此问题,本文针对采用各向同性泄漏项和各向异性泄漏项2种情况,对GET-CMFD中的轴向节块不连续因子(NDF)和轴向修正扩散因子(MDF)进行改进,同时对2D/1D耦合算法中关键的泄漏项分割技术的使用条件进行系统研究。计算结果显示:GET-CMFD方法中轴向NDF和轴向MDF采用2D MOC计算归并的通量进行计算,同时2D/1D算法中泄漏项采用最新更新的数值可以获得好的收敛性。泄漏项分割方法的使用条件采用出射角通量小于0修正可以在保证收敛性的同时降低精度损失。在一次2D/1D迭代过程内采用2次S_(N)计算可以在计算量几乎不提升的前提下,显著降低迭代次数,提高收敛性。通过对GET-CMFD方法,泄漏项分割技术使用条件以及迭代流程的改进,算法的收敛性可以得到明显提高。 展开更多
关键词 广义等价理论的CMFd 2d/1d 节块不连续因子(NdF) 修正扩散因子(MdF) 各向同性泄漏项 各向异性泄漏项 泄漏项分割方法
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Simulation of the Hydrodynamic Functioning of the Cavally River Using a Coupled 1D-2D Model in the Ity Area (Zouan-Hounien in Côte d’Ivoire)
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作者 Affoué Berthe Yao Kouao Armand Anoh +2 位作者 Loukou Alexis Brou Menouan Wilfried Goli Lazare Kouakou Kouassi 《Open Journal of Modern Hydrology》 2021年第4期75-84,共10页
In recent years, the Cavally River has been subject to multiple activities, <span style="font-family:;" "="">including the construction of diversion channels and a bridge that makes it v... In recent years, the Cavally River has been subject to multiple activities, <span style="font-family:;" "="">including the construction of diversion channels and a bridge that makes it vulnerable to flooding. In order to assess the impact of these hydraulic structures on the <span>river hydrodynamic functioning, a 1D-2D model was realized. The</span> implementation of the 1D-2D model consisted </span><span style="font-family:;" "="">of </span><span style="font-family:;" "="">first </span><span style="font-family:;" "="">running</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">the 1D model, then the 2D model, and finally in coupling them. The 1D-2D model was designed with <span>the 1988 flood hydrograph, a Manning’s coefficient of 0.052 m<sup>1/3</sup>/s for the </span>minor bed and 0.06 m<sup>1/3</sup>/s for the major bed. The results of the hydraulic model show that the velocities are almost identical to those of the Cavally in natural operation. The values of the velocities are included between 0.4 m/s and 1.3 m/s at the level of the minor bed of the river and between 0.06 m/s and 0.71 m/s at the level of the floodplains. The average water level for flood propagation is 262.37 ± 0.44 m before construction of the structures and 262.23 ± <span>0.85 m after construction of the structures. The 0.41 m reduction in water</span> level due to the diversion canal and bridge is negligible compared to the total fluctuations of the Cavally River, which vary from 6 to 7 m over the year.</span> 展开更多
关键词 Ity Mines 1d-2d Modeling FLOOdING Cavally River Côte d’Ivoire
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n-十二烷基-β-D-麦芽糖苷与十二烷基三甲基氯化铵混合胶束的^1HNMR研究 被引量:4
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作者 杨秋青 刘博谦 李秀瑜 《化学学报》 SCIE CAS CSCD 北大核心 2008年第17期1949-1954,共6页
利用NMR技术的自扩散、自旋-自旋弛豫时间(T2)和自旋-晶格弛豫时间(T1)以及二维NOESY谱,研究了n-十二烷基-β-D-麦芽糖苷(DM)与十二烷基三甲基氯化铵(DTAC)的二元混合体系中混合胶束的形成、大小变化、排列方式、复配比例和相互作用点等... 利用NMR技术的自扩散、自旋-自旋弛豫时间(T2)和自旋-晶格弛豫时间(T1)以及二维NOESY谱,研究了n-十二烷基-β-D-麦芽糖苷(DM)与十二烷基三甲基氯化铵(DTAC)的二元混合体系中混合胶束的形成、大小变化、排列方式、复配比例和相互作用点等.NMR的自扩散系数表明了混合胶束的大小主要取决于DM分子,T2/T1显示混合胶束堆积的较紧密,两分子的疏水链是以肩并肩的方式位于胶束核中,2D NOESY谱表明DTAC分子中与极头相连的亚甲基邻近DM分子中倒数第二个糖环,产生分子间相互作用,其相互作用和分子间距的大小随DM/DTAC比例的不同而变化,DM/DTAC在1∶4和1∶8之间是较好的复配比例范围,并确定混合前后出现的相反变化T2值是混合胶束中产生相互作用的证据. 展开更多
关键词 n-十二烷基-β-d-麦芽糖苷 十二烷基三甲基氯化铵 混合胶束结构 相互作用点 复配比例 ^1HNMR
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A Zn(Ⅱ) Coordination Polymer Based on a Flexible Polycarboxylate Ligand 5-(4-Hydroxypyridinium-1-ylmethyl)-isophthalic Acid: Synthesis, Structure, and Property 被引量:1
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作者 李付安 杨维春 李青彬 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第4期645-652,共8页
A Zn(Ⅱ) supramolecular coordination polymer, {[Zn2(L)2(m-bix)(H20)]6H2O}n(1), with an interesting 1D→2D polythreading array from a flexible and angular organic aromaticpolycarboxylate ligand 5-(4-hydroxyp... A Zn(Ⅱ) supramolecular coordination polymer, {[Zn2(L)2(m-bix)(H20)]6H2O}n(1), with an interesting 1D→2D polythreading array from a flexible and angular organic aromaticpolycarboxylate ligand 5-(4-hydroxypyridinium-l-ylmethyl)isophthalic acid (H2L), and N-donorligand 1,3-bis(imidazol-l-ylmethyl)benzene (m-bix), has been obtained under hydrothermalconditions and characterized by elemental analysis, powder X-ray diffraction (PXRD), IR, thermalgravimetric analyses (TGA) and single-crystal X-ray diffraction. In 1, the Zn(Ⅱ) center has twocoordination geometries. One exhibits a trigonal bipyramidal coordination sphere, and the other isa tetrahedral geometry; L2- has two different coordination modes, with one connecting three Zn(Ⅱ)ions through two monodentate carboxylate groups and the monodentate hydroxyl group, and theother bridging two Zn(Ⅱ) ions through two carboxylate groups. The L2- anions connect the Zn(Ⅱ)centers forming an infinite 1D tubular structure. These 1D tubes are interconnected by the m-bixspacers to form a 2D framework. Such 2D layers are further assembled into a 3D supramolecularnetwork via hydrogen bonds. Meanwhile, the luminescent property of 1 has also been investigatedin detail. 展开更多
关键词 5-(4-hydroxypyridinium-1-ylmethyl)isophthalic acid 1 3-bis(imidazol-1-ylmethyl)benzene ZINC PXRd 1d2d polythreading array
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