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Effect of the lenticles on moisture migration in capillary zone of tailings dam

International Journal of minerals,Metallurgy and Materials 2020年第8期27卷 1036-1045页

作者： Di Liu min-jie lian Cai-wu Lu Wen Zhang College of Materials Science and Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Institute of mining System Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Sinosteel mining Co. Ltd.Beijing 100080China School of Resource Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

Small-particle interlayers(lenticles)show some characteristic hydraulic properties and can affect the movement of unsaturated *** this study,we developed a novel online capillary-water-absorption monitoring device and conducted three groups of comparison tests to simulate lenticle positions and thicknesses with respect to the capillary *** results show that the characteristic wetting front exhibits a fast rise in the early stage,a slow rise in the middle stage,and stability in the later *** motion of the capillary water in the lenticle is mainly transversal,with the upward curve being"flat,"and the longer is"flat,"the longer is the time needed for the water to *** interlayer can form a capillary stagnation zone with moisture content close to *** high interlayer may form a discontinuous corrugated capillary ***,when the wetting front reaches the"coarse-grain(lower)-fine-grain(upper)"interface,the"anti-capillary barrier effect"results in more moisture in the upper ***,when the wetting front of the capillary water reaches the"fine-grain(upper)-coarse-grain(lower)"interface,the"capillary barrier effect"causes the moisture content of the upper tailings to decreases sharply because of the horizontal movement of the water in the fine *** is clear that the presence of lenticles can retard the rise of capillary water by storing water.

关键词： tailings lenticle moisture migration capillary retarding effect microcosmic mechanism

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巫峡长江大桥施工加载过程计算

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同济大学学报（自然科学版） 2004年第11期32卷 1413-1417页

作者：张建民郑皆连肖汝诚同济大学桥梁工程系上海200092 广西交通厅广西南宁530011

对钢管内混凝土的收缩徐变特性进行了分析 ,结合有限元步进法和按龄期调整的有效模量法 ,编制了相应的计算程序 .根据巫峡长江大桥实际划分的施工时段 ,计算桥梁从施工到成桥各个时刻钢管和核心混凝土的应力 ,并提出了一些建议 .

关键词：拱桥施工控制钢管混凝土

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Dynamical complexity of Anosov systems driven by a quasi-periodic force

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Science China Mathematics 2025年第1期 89-136页

作者： Wen Huang Zeng lian Kening Lu Department of Mathematics University of Science and Technology of China School of Mathematics Sichuan University

Consider C2Anosov systems on a compact manifold driven by a quasi-periodic *** study their dynamical complexity on various levels from the perspectives of both path-wise dynamics and stochastic *** that these systems are non-wandering（i.e.,every point in the phase space is nonwandering）,we prove a set of results:（1） the existence of abundance of random periodic points;（2） a random Liv?ic theorem;（3） a random Ma?é-Bousch-Conze-Guivarc'h lemma;（4） the existence of strong random ***,a concrete example constructed on a 2-dimensional torus is also given to uncover some interesting phenomena of the systems.

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Recent Progress in Carbon-based Materials of Non-Noble Metal Catalysts for ORR in Acidic Environment

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Acta Metallurgica Sinica(English Letters) 2021年第7期34卷 885-899页

作者： jie lian Jin-Yu Zhao Xiao-min Wang College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Shanxi Key Laboratory of New Energy Materials and Devices Taiyuan University of TechnologyTaiyuan 030024China

Proton exchange membrane fuel cell(PEMFC)has important implications for the success of clean transportation in the *** of the key factors affecting the cost and performance of PEMFC is the cathode electrocatalyst for the oxygen reduction reaction(ORR)to overcome sluggish kinetics and instability in an acidic *** an essential component of the electrocatalyst,the support material largely determines the activity,mass transfer,charge transfer,and durability of the ***,the support material plays a critical role in the overall performance of the *** materials are widely used as electrocatalyst supports because of their high porosity,conductivity,chemical stability,and tunable ***,some new carbon-based materials with excellent structure have been introduced,such as carbon nanotubes,carbon nanowires,graphene,metal-organic framework(MOF)-derived carbon,and biomass-derived carbon *** with a variety of strategies,such as controllable construction of porous structures and surface defects,proper doping heteroatoms,the ingenious design of model electrocatalysts,and predictive theoretical calculation,a new reliable path was provided for further improving the performance of electrocatalysts and exploring the catalytic *** on the topic of carbon-based materials for ORR in acidic medium,this review summarizes the up-to-date progress and breakthroughs,highlights the factors affecting the catalytic activity and stability of ORR electrocatalysts in acids,and discusses their future application and development.

关键词： Carbon-based materials Non-noble metal electrocatalysts Acidic environment Oxygen reduction reaction Proton exchange membrane fuel cell

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Supercapacitors based on high-surface-area graphene

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Science China(Technological Sciences) 2014年第2期57卷 278-283页

作者： ZHOU XiaoLin WANG min lian jie lian YongFu Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Material Science Heilongjiang University

Exfoliated graphite oxide was prepared by an improved Hummers method and was then reduced to graphene with hydrazine in the presence of ammonium hydroxide.N2adsorption–desorption measurement showed that graphene so obtained had a specific surface area as high as 818 m2/*** charge/discharge curves demonstrated that the as-prepared graphene exhibited a specific capacitance of 186.9 F/g at a current density of 0.1 A/g and that about 96%of the specific capacitance was retained after 2000 cycles at a current density of 5 A/g.

关键词： supercapacitor graphene high specific surface area high specific capacitance

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Variation of Zn content in soils under different land-use types in the Hetao oasis,Inner Mongolia of China

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Journal of Arid Land 2016年第6期8卷 861-870页

作者： ZHU Yangchun ZHAO Xueyong lian jie CHEN min Naiman Desertification Research Station/Urat Desert-grassland Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Understanding the status and distribution of the micronutrient Zn in soils is important for managing plant growth and preventing soil pollution for agricultural irrigation systems in arid and semi-arid regions. In this study, a total of 195 soil samples from five soil layers （0-20, 20-40, 40-60, 60-80 and 80-100 cm） in the three land-use types （wasteland, forestland and cropland） after long-term agricultural fertilization and irrigation with Yellow River water were collected in the middle of the Hetao oasis, i.e. the Yongji irrigation sub-oasis. We analyzed the vertical and spatial distributions of Zn content and its relationship with soil properties to determine whether differences of Zn content existed in the soil profiles. The results revealed that the mean content of Zn was 107 mg/kg, 1.9 times higher than the background value （55.7 mg/kg） of the Hetao oasis and much lower than the secondary standard value （300 mg/kg） of the Chinese Environmental Quality Standard for Soils when pH〉7.5. Soil Zn contents were not significantly different and the coefficients of variation of Zn contents were less than 50% in the five soil layers. Soil Zn content was similar from southern to northern parts but increased from western to eastern parts in the sub-oasis. Soil Zn contents did not differ significantly among the three land-use types, but soil total nitrogen （TN） contents were significantly higher in the agriculturally managed forestland and cropland than in the wasteland （P〈0.05）. Zn was significantly and positively correlated with TN （F=36.6, P〈0.001）. The use of fertilizers may increase the content of Zn in soils, but flooding irrigation may minimize the differences in the spatial distribution of soil Zn content in the whole sub-oasis. This research is of important value for soil pollution control and sustainable land use management in arid and semi-arid regions.

关键词： fertilizer land-use type spatial distribution soil profile soil property

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Photo‑Energized MoS_(2)/CNT Cathode for High‑Performance Li–CO_(2)Batteries in a Wide‑Temperature Range

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Nano-Micro Letters 2025年第1期17卷 160-175页

作者： Tingsong Hu Wenyi lian Kang Hu Qiuju Li Xueliang Cui Tengyu Yao Laifa Shen Jiangsu Key Laboratory of Materials and Technologies for Energy Storage College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction ***,a photo-energized strategy adopting sustainable solar energy in wide working temperature range Li–CO_(2) battery was achieved with a binder-free MoS_(2)/carbon nanotube(CNT)photo-electrode as *** unique layered structure and excellent photoelectric properties of MoS_(2) facilitate the abundant generation and rapid transfer of photo-excited carriers,which accelerate the CO_(2) reduction and Li_(2)CO_(3) decomposition upon *** illuminated battery at room temperature exhibited high discharge voltage of 2.95 V and mitigated charge voltage of 3.27 V,attaining superior energy efficiency of 90.2%and excellent cycling stability of over 120 *** at an extremely low temperature of−30℃,the battery with same electrolyte can still deliver a small polarization of 0.45 V by the photoelectric and photothermal synergistic mechanism of MoS_(2)/CNT *** work demonstrates the promising potential of the photo-energized wide working temperature range Li–CO_(2) battery in addressing the obstacle of charge overpotential and energy efficiency.

关键词： Li-CO_(2)batteries Photo-energized Wide operation-temperature Kinetics MoS_(2)

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Floral traits and pollination system of Zygophyllum xanthoxylum in the managed and wild populations in an arid region of Northwest China

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Journal of Arid Land 2015年第4期7卷 488-500页

作者： CHEN min ZHAO Xueyong ZUO Xiao'an lian jie ZHU Yangchun Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences

Zygophyllum xanthoxylum, which belongs to Sarcozygium of Zygophyllaceae, is one of the ecologically important species in Northwest China. In order to understand the pollination system of Z. xanthoxylum, we investigated the following characteristics of this species in the Urat Desert-grassland Research Station in western Inner Mongolia of China： flowering dynamics, pollen viability, pollen limitation, floral visitors and breeding system. The results showed that the flowering period and flowering peak were different between the wild and managed popula- tions, being longer in the managed population. Z. xanthoxylum was pollen-limited, and pollen limitation was more intense in the wild population than in the managed population. Chalicodoma deserticola （Hymenoptera） was found to be the most frequent pollinator in the wild population, while Anthophora fulvitarsis （Hymenoptera） was the most frequent and effective visitor in the managed population. Out-crossing was dominant in the breeding system and self-pollination just played an assistant role to assure the reproduction of Z. xanthoxylum.

关键词： Zygophyllum xanthoxylum pollination pollen limitation floral visitor fruit set seed set breeding system

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Synthesis,Crystal Structure and Fluorescence of a Three-dimensional Cd(II) Coordination Polymer [Cd(μ_(1,3)- SCN^-)_2(μ-dmpo)]_n (dmpo = 3,5-Dimethylpyridine N-Oxide)

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Chinese Journal of Structural Chemistry 2006年第7期25卷 779-782页

作者： SHI Jing-min ZHANG Feng-Xia HUANG jie LIU lian-Dong Department of Chemistry Shandong Normal University Jinan 250014 China Department of Chemistry Qingdao Normal College of Qingdao University Qingdao 266002 China

A three-dimensional complex [Cd（μ1,3-SCN）2（dmpo）]n has been synthesized with μ1,3-SCN^- and dmpo as mixed bridge ligands. The crystal belongs to monoclinic, space group C2/c with a = 15.648（2）, b = 15.126（2）, c = 11.9773（15） A, β= 112.416（2）°, V= 2620.7（6） ,A, Z= 8, C9H9CdN3OS2, Mr = 351.71, Dc = 1.783 g/cm^3, F（000） = 1376 and μ = 1.967 mm^-1. The structure was refined to R = 0.0260 and wR = 0.0647 for 2186 observed reflections （I 〉 2σ（I））. In the crystal the Cd（Ⅱ） ions are coordinated by ,μ1,3-SCN^- bridge ligands to form the crossing chains on the adjacent planes, and these chains are further joined by μ-dmpo mono-dentate bridge ligands leading to a three-dimensional structure. The complex exhibits strong fluorescent emission property.

关键词： crystal structure cadmium(Ⅱ) complex fluorescence aromatic N-oxide ligand thiocyanate ligand

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Relation Enhanced Neural Model for Type Classification of EntityMentions with a Fine-Grained Taxonomy

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Journal of Computer Science & Technology 2017年第4期32卷 814-827页

作者： Kai-Yuan Cui Peng-jie Ren Zhu-min Chen Tao lian Jun Ma Information Retrieval Laboratory School of Coutputer Science and Technology Shandong University Jinan 250101 China

Inferring semantic types of the entity mentions in a sentence is a necessary yet challenging task. Most of existing methods employ a very coarse-grained type taxonomy, which is too general and not exact enough for many tasks. However, the performances of the methods drop sharply when we extend the type taxonomy to a fine-grained one with several hundreds of types. In this paper, we introduce a hybrid neural network model for type classification of entity mentions with a fine-grained taxonomy. There are four components in our model, namely, the entity mention component, the context component, the relation component, the already known type component, which are used to extract features from the target entity mention, context, relations and already known types of the entity mentions in surrounding context respectively. The learned features by the four components are concatenated and fed into a softmax layer to predict the type distribution. We carried out extensive experiments to evaluate our proposed model. Experimental results demonstrate that our model achieves state-of-the-art performance on the FIGER dataset. Moreover, we extracted larger datasets from Wikipedia and DBpedia. On the larger datasets, our model achieves the comparable performance to the state-of-the-art methods with the coarse-grained type taxonomy, but performs much better than those methods with the fine-grained type taxonomy in terms of micro-F1, macro-F1 and weighted-F1.

关键词： entity mention classification entity mention relation fine-grained taxonomy

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