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柳江盆地髫髻山组凝灰岩地球化学与熔体包裹体水含量特征

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岩矿测试 2025年第1期44卷 88-101页

作者：赵汇珍陈勇涂聪冯艳伟中国石油大学(华东)深层油气全国重点实验室山东青岛266580 中国石油大学(华东)地球科学与技术学院山东青岛266580 中国科学技术大学地球和空间科学学院安徽合肥230026

水作为岩浆体系中最主要的挥发组分,对岩浆的形成和演化有重要的影响,柳江盆地髫髻山组岩浆岩是燕山期火山活动的重要产物,尽管前人对其地球化学特征进行了大量研究,但关于柳江盆地燕山期岩浆中的水含量仍不清楚。熔体包裹体记录了原始... 详细信息

水作为岩浆体系中最主要的挥发组分,对岩浆的形成和演化有重要的影响,柳江盆地髫髻山组岩浆岩是燕山期火山活动的重要产物,尽管前人对其地球化学特征进行了大量研究,但关于柳江盆地燕山期岩浆中的水含量仍不清楚。熔体包裹体记录了原始岩浆信息,是获取岩浆水含量特征的最直接样品。本文基于全岩地球化学分析,利用标准样品建立了显微激光拉曼光谱定量熔体包裹体水含量的标定曲线,并对柳江盆地髫髻山组下部流纹质岩屑-晶屑凝灰岩中石英斑晶内的原生熔体包裹体进行了水含量定量分析。结果表明:髫髻山组下部凝灰岩样品具有富Si、Al、大离子亲石元素富集、高场强元素亏损、轻稀土富集、重稀土亏损、负Eu异常、Sr含量低等特点;熔体包裹体中水含量的定量分析结果为0.99%~4.98%,平均水含量为2.62%,与前人统计的酸性岩浆水含量基本一致。地球化学特征和熔体包裹体水含量分析结果共同揭示了研究区髫髻山期早期为富水酸性岩浆。结合髫髻山期样品的熔体包裹体水含量测定结果及其早期的大规模火山喷发背景,本文认为岩浆中高含水量增强了岩浆系统的喷发动力,是诱发研究区髫髻山期早期大规模火山爆发的有利因素之一。

关键词：柳江盆地髫髻山组凝灰岩熔体包裹体水含量显微激光拉曼光谱法

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Intensified photocatalytic degradation of nitrobenzene by Pickering emulsion of ZnO nanoparticles

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Particuology 2010年第5期8卷 453-457页

作者： wei Wu Shuang Gao weixia tu jianfeng Chen Pengyuan Zhang Key Laboratory for Nanomaterials Ministry of Education Beijing University of Chemical Technology Beijing 100029 China Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing 100029 China

In this paper, zinc oxide nanoparticles were first prepared and surface-modified. A Pickering emulsion was then prepared, consisting of nitrobenzene （oil phase）, water （water phase） and the modified zinc oxide nanoparticles located on the water-oil interface. The effects of different emulsions on the removal rate of nitrobenzene by photocatalytic degradation were studied. The results proved that use of a Pickering emulsion stabilized by surface-modified ZnO nanoparticles provides an effective and novel way to intensify the photocatalytic degradation of the organic contaminant.

关键词： Pickering emulsionZinc oxidePhotocatalysisNitrobenzene

Isothermal reduction of titanomagnetite concentrates containing coal

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International Journal of Minerals,Metallurgy and Materials 2014年第2期21卷 131-137页

作者： tu Hu Xue-wei Lü Chen-guang Bai Gui-bao Qiu College of Materials Science and Engineering Chongqing University Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology

The isothermal reduction of the Panzhihua titanomagnetite concentrates （PTC） briquette containing coal under argon atmosphere was investigated by thermogravimetry in an electric resistance furnace within the temperature range of 1250-1350°C. The samples reduced in argon at 1350°C for different time were examined by X-ray diffraction （XRD） analysis. Model-fitting and model-free methods were used to evaluate the apparent activation energy of the reduction reaction. It is found that the reduction rate is very fast at the early stage, and then, at a later stage, the reduction rate becomes slow and decreases gradually to the end of the reduction. It is also observed that the reduction of PTC by coal depends greatly on the temperature. At high temperatures, the reduction degree reaches high values faster and the final value achieved is higher than at low temperatures. The final phase composition of the reduced PTC-coal briquette consists in iron and fer-rous-pseudobrookite （FeTi2O5）, while Fe2.75Ti0.25O4, Fe2.5Ti0.5O4, Fe2.25Ti0.75O4, ilmenite （FeTiO3） and wustite （FeO） are intermediate products. The reaction rate is controlled by the phase boundary reaction for reduction degree less than 0.2 with an apparent activation energy of about 68 kJ·mol-1 and by three-dimensional diffusion for reduction degree greater than 0.75 with an apparent activation energy of about 134 kJ·mol-1. For the reduction degree in the range of 0.2-0.75, the reaction rate is under mixed control, and the activation energy increases with the increase of the reduction degree.

关键词： titanomagnetite carbothermal reduction thermogravimetric analysis kinetics

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基于三点弯曲试验的坝体模型材料研究

水电能源科学 2025年第1期43卷 70-73,191页

作者：黄冠涂劲钟红中国水利水电科学研究院北京100048

我国西南西北强地震区建设有多座高混凝土坝,采取适宜的抗震措施可有效改善大坝的抗震性能。纤维混凝土为混凝土坝抗震加固措施之一,为研究纤维混凝土模型材料的抗弯性能随纤维掺量的变化,按照质量掺量,设计1组对照组(0%)和6组试验组(0.... 详细信息

我国西南西北强地震区建设有多座高混凝土坝,采取适宜的抗震措施可有效改善大坝的抗震性能。纤维混凝土为混凝土坝抗震加固措施之一,为研究纤维混凝土模型材料的抗弯性能随纤维掺量的变化,按照质量掺量,设计1组对照组(0%)和6组试验组(0.17%、0.33%、0.67%、1.00%、1.33%、1.67%),采用三点弯曲试验测试了纤维混凝土的抗弯性能。结果表明,纤维掺量对材料的强度和变形性能影响均很大;随着纤维掺量的提高,材料的抗弯强度先略有降低之后明显提高,掺量为1.00%时,试块的弯拉强度最大,之后随着掺量提高强度不再增长;峰值荷载位移与纤维掺量大体上呈线性关系。

关键词：混凝土坝模型材料麻纤维纤维混凝土三点弯曲试验弯拉强度峰值荷载位移

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Interpolation Method of Head-Related Transfer Functions Based on Common-Pole/Zero Modeling

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China Communications 2020年第10期17卷 170-182页

作者： wei Chen Xiaochen Wang Ruimin Hu Gang Li weiping tu National Engineering Research Center for Multimedia Software School of Computer ScienceWuhan UniversityWuhan 430072China Hubei Key Laboratory of Multimedia and Network Communication Engineering Wuhan UniversityWuhan 430072China Research Institute of Wuhan University in Shenzhen China

The head-related transfer function(HRTF)involves the cues for human auditory localization,which turns it into an essential item of virtual auditory display *** practice,the interpolation of HRTF is necessary for the virtual auditory display systems to achieve high spatial *** geometric-based interpolation methods are generally restrained by the spatial distribution of reference on *** the spatial distribution is sparse,the accuracy of interpolation decreases ***,an interpolation method using the common-pole/zero model and the fitting neural network is ***,we propose a common-pole/zero model to represent HRTFs across multiple subjects,in which the low-dimensional features of the measured HRTFs are ***,for a new spatial direction,we predict the corresponding low-dimensional HRTF with a fitting neural ***,we reconstruct the high-dimensional HRTF from the predicted low-dimensional *** simulation results suggest that the proposed method outperforms other interpolation methods such as Linear_AMBC,Bilinear_AMBC,and the Combination method.

关键词： HRTF interpolation fitting neural network common-pole/zero model

Non-permanent Pole-to-pole Fault Restoration Strategy for Flexible DC Distribution Network

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Journal of Modern Power Systems and Clean Energy 2021年第6期9卷 1339-1351页

作者： Zainan Li jiandong Duan Wenchao Lu Xiaotong Du wei Yang Siyu tu School of Electrical Engineering Xi’an University of Technology State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(North China Electric Power University) State Grid Hubei Maintenance Company

As the structures of multiple branch lines(MBLs)will be widely applied in the future flexible DC distribution network,there is a urgent need for improving system reliability by tackling the frequent non-permanent pole-to-pole(P-P)fault on distribution lines.A novel fault restoration strategy based on local information is proposed to solve this *** strategy firstly splits a double-ended power supply network into two single-ended power supply networks through the timing difference characteristics of a hybrid direct current circuit breaker(HDCCB)entering the ***,a method based on the characteristic of the transient energy of fault current is proposed to screen the faulty branch line in each single-ended power supply ***,a four-terminal flexible DC distribution network with MBLs is constructed on PSCAD to demonstrate the efficacy of the proposed *** factors such as noise,fault location,and DC arc equivalent resistance are considered in the simulation model for *** results prove that the proposed strategy for fault restoration is effective,and features high performance and scalability.

关键词： Flexible DC distribution network pole-to-pole fault fault restoration strategy reclosing strategy transient energy of fault current

K-doped BaCo_(0.4)Fe_(0.4)Zr_(0.2)O_(3−δ) as a promising cathode material for protonic ceramic fuel cells

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Journal of Advanced Ceramics 2022年第12期11卷 1988-2000页

作者： Peng QIU Bo LIU Lei WU Huiying QI Baofeng tu jian LI Lichao jia School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Center for Fuel Cell Innovation School of Materials Science and EngineeringState Key Lab of Materials Processing and Die&Mound TechnologyHuazhong University of Science and TechnologyWuhan 430074China College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdao 266590China

Slow oxygen reduction reaction(ORR)involving proton transport remains the limiting factor for electrochemical performance of proton-conducting *** further reduce the operating temperature of protonic ceramic fuel cells(PCFCs),developing triple-conducting cathodes with excellent electrochemical performance is *** this study,K-doped BaCo_(0.4)Fe_(0.4)Zr_(0.2)O_(3−δ)(BCFZ442)series were developed and used as the cathodes of the PCFCs,and their crystal structure,conductivity,hydration capability,and electrochemical performance were characterized in *** them,Ba_(0.9)K_(0.1)Co_(0.4)Fe_(0.4)Zr_(0.2)O_(3−δ)(K10)cathode has the best electrochemical performance,which can be attributed to its high electron(e^(−))/oxygen ion(O^(2−))/H^(+)conductivity and proton uptake *** 750℃,the polarization resistance of the K10 cathode is only 0.009Ω·cm^(2),the peak power density(PPD)of the single cell with the K10 cathode is close to 1 W·cm^(−2),and there is no significant degradation within 150 *** electrochemical performance and durability make K10 a promising cathode material for the *** work can provide a guidance for further improving the proton transport capability of the triple-conducting oxides,which is of great significance for developing the PCFC cathodes with excellent electrochemical performance.

关键词： proton transport proton-conducting cathode protonic ceramic fuel cells(PCFCs) triple-conducting hydration capability

Exploring metro vibrancy and its relationship with built environment:a cross-city comparison using multi-source urban data

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Geo-Spatial Information Science 2022年第2期25卷 182-196页

作者： wei tu Tingting Zhu Chen Zhong Xiaohu Zhang Yang Xu Qingquan Li Guangdong Key Laboratory of Urban Informatics and Shenzhen Key Laboratory of Spatial Smart Sensing and ServiceSchool of Architecture and Urban PlanningShenzhen UniversityShenzhenChina Ministry of Natural Resources(MNR)Key Laboratory for Geo-Environmental Monitoring of Great Bay Area Shenzhen UniversityShenzhenChina The Bartlett Centre for Advanced Spatial Analysis(CASA) University College London(UCL)LondonUK Department of Urban Planning and Design The University of Hong KongHong KongChina Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong Kong SARChina

Recent urban transformations have led to critical reflections on the blighted urban infrastruc-tures and called for re-stimulating vital urban ***,the metro has been recognized as the backbone infrastructure for urban mobility and the associated economy *** date,limited research has been devoted to investigating the relationship between metro vitality and built environment in mega-cities *** paper presents a multisource urban data-driven approach to quantify the metro vibrancy and its association with the underlying built *** smart card data is processed to extract metro ridership,which denotes the vibrancy around the metro station in physical *** media check-ins are crawled to measure the vitality of metros in virtual *** physical and virtual vibrancy are integrated into a holistic metro vibrancy metric using an entropy-based weighting *** built environment characteristics,including land use,transportation and buildings are modeled as independent *** significant influences of built environ-mental factors on the metro vibrancy are unraveled using the ordinary least square regression and the spatial lag *** experiments conducted in Shenzhen,Singapore and London,this study comes up with a conclusion that spatial distributions of metro vibrancy metrics in three cities are spatially *** regression analysis suggests that in all the three cities,more affluent urban areas tend to have higher metro virbrancy,while the road density,land use and buildings tend to impact metro vibrancy in only one or two *** results demonstrate the relationship between the metro vibrancy and built environment is affected by complex urban *** findings help us to understand metro vibrancy thus make proper policy to re-stimulate the important metro infrastructure in the future.

关键词： Urban vibrancy spatial-autocorrelation spatial lag model smart card data social media

Toughness enhancement of single-crystal diamond by the homoepitaxial growth of periodic nitrogen-doped nano-multilayers

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International Journal of Minerals,Metallurgy and Materials 2023年第4期30卷 766-771页

作者： Yun Zhao Juping tu Liangxian Chen Junjun wei Jinlong Liu Chengming Li The Future Laboratory Tsinghua UniversityBeijing 100084China Academy of Arts&Design Tsinghua UniversityBeijing 100084China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China College of Science China Agricultural UniversityBeijing 100083China

Periodic nitrogen-doped homoepitaxial nano-multilayers were grown by microwave plasma chemical vapor deposition. The residual time of gases(such as CH4and N2) in the chamber was determined by optical emission spectroscopy to determine the nano-multilayer growth process, and thin, nanoscale nitrogen-doped layers were obtained. The highest toughness of 18.2 MPa·m^(1/2)under a Young’s modulus of1000 GPa is obtained when the single-layer thickness of periodic nitrogen-doped nano-multilayers is about 96 nm. The fracture toughness of periodic nitrogen-doped CVD layer is about 2.1 times that of the HPHT seed substrate. Alternating tensile and compressive stresses are derived from periodic nitrogen doping;hence, the fracture toughness is significantly improved. Single-crystal diamond with a high toughness demonstrates wide application prospects for high-pressure anvils and single-point diamond cutting tools.

关键词： microwave plasma chemical vapor deposition diamond fracture toughness nitrogen doping