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Journal of Energy Chemistry 2018年第3期27卷 913-922页

作者： qiao cheng Dong Wang Huanping Zhou Department of Energy and Resources Engineerirzg College of EngineeringPeking UniversityBeUing 100871China

Zn（O,S）（zinc oxysulfide） is an important chalcogenide material recently reported to be potentially applied as electrode buffers in thin film solar cells. Both vacuum and solution approaches have enabled the fabrication of Zn（O,S） films. However they either require extreme conditions and high energy consumption for synthesis, or suffer from lack of controllability mainly due to the thermodynamic and kinetic distinction between Zn O and Zn S during film growth. Here we demonstrated an effective electrodeposition route to obtain high-quality Zn（O,S） thin films in a controllable manner. Importantly, tartaric acid was employed as a secondary complexing agent in the electrolyte to improve the film morphology, as well as to adjust other key properties such as composition and absorption. To elucidate the vital role that tartaric acid played, thermodynamic and kinetic processes of electrodeposition was investigated and discussed in detail. The accumulative contribution has shed light on further exploit of Zn（O,S） with tunable properties and optimization of the corresponding electrodeposition process, for the application in thin film solar cells.

关键词： Zinc oxysulfide Zn(O S) Electrodeposition Tartaric acid

Spatial relationship-assisted classification from high-resolution remote sensing imagery

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International Journal of Digital Earth 2015年第9期8卷 710-726页

作者： cheng qiao Jinfei Wang Jiali Shang Bahram Daneshfar Department of Geography The University of Western OntarioLondonONCanada Science&Technology Branch Agriculture and Agri-Food CanadaOttawaONCanada

Spatial information remains to be an important topic in geographic information system and in remote sensing fields,and spatial relationships have been increasingly incorporated into the image classification *** studies have employed multiple occurrences of spatial features(shape,texture,etc.,)to improve classification ***,less attention has been focused on using higher-level spatial relationships for image *** this study,two novel spatial relationships,namely,maximum spatial adjacency(MSA)and directional spatial adjacency(DSA),were proposed to assist in image *** proposed methods were implemented to extract buildings,beach,and emergent vegetation land-cover classes according to their spatial relationships with their corresponding reference *** promising results obtained from this study suggest that the proposed MSA and DSA spatial relationships can be valuable information in defining rule sets for a more reasonable and accurate classification.

关键词： spatial relationship image classification high-resolution imagery maximum spatial adjacency directional spatial adjacency

Characterization of the fracture compressibility and its permeability for shale under the effects of proppant embedment and compaction:A preliminary study

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Petroleum Science 2022年第3期19卷 1125-1138页

作者： Jian-Hua Li Bo-Bo Li qiao-Yun cheng Zheng Gao Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen518060GuangdongChina Shenzhen Key Laboratory of Deep Underground Engineering Sciences and Green Energy Shenzhen UniversityShenzhen518060GuangdongChina College of Mining Guizhou UniversityGuiyang550025GuizhouChina Guizhou Key Laboratory of Comprehensive Utilization of Non-metallic Mineral Resources Guiyang550025GuizhouChina National&Local Joint Laboratory of Engineering for Effective Utilization of Regional Mineral Resources from Karst Areas Guizhou UniversityGuiyang550025GuizhouChina

Hydraulic fracturing technology plays a key role in improving the recovery rate of shale *** improvement of permeability in relation to hydraulic fracturing depends on changes brought about by the proppant on the fracture structure in *** it is of great significance to describe the microscopic changes during this process by means of an accurate theoretical *** this study,based on the heterogeneity of shale fracture and the compaction and embedment of a proppant,we proposed a permeability model to examine the combined effects of a proppant and stress to describe the change mechanism in ***,changes in fracture width and porosity were considered,and a calculation model of fracture compressibility under proppant compaction and embedment was *** difference from previous studies is that the compressibility and permeability of supported fractures can be further quantified and analyzed by this ***,its rationality was verified by publicly released test *** results show that,the compressive effect of stress and the embedding of proppant both have a negative impact on shale permeability.

关键词： Shale Fracture compressibility Permeability Hydraulic fracturing Proppant embedment

Norm Equalities and Inequalities for Three Circulant Operator Matrices

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Acta Mathematica Sinica,English Series 2017年第4期33卷 571-590页

作者： Zhao Lin JIANG Yun cheng qiao Shu Dong WANG School of Sciences Linyi University Linyi 276005 P. R. China

In this paper, three new circulant operator matrices, scaled circulant operator matrices,diag-circulant operator matrices and retrocirculant operator matrices, are given respectively. Several norm equalities and inequalities for these operator matrices are proved. We show the special cases for norm equalities and inequalities, such as the usual operator norm and the Schatten p-norm. Pinching type inequality is also given for weakly unitarily invariant norms. These results are closely related to the nice structure of these special operator matrices. Furthermore, some special cases and specific examples are also considered.

关键词： Operator matrix norm scaled circulant diag-circulant retrocirculant

Transfer Learning via Linear Multi-variable Mapping under Reinforcement Learning Framework 36

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Transfer Learning via Linear Multi-variable Mapping under Re...

Debris Flow Formation Process and Critical Hydrodynamic Conditions in the Meizoseismal Area of the Wenchuan Earthquake

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作者： qiao cheng Xiangke Wang Lincheng Shen College of Mechatronics and Automation National University of Defense Technology

ISBN: (纸本)9781538629185

Though popular in many agent learning tasks,reinforcement learning still faces problems,such as long learning time in complex *** learning could shorten the learning time and improve the performance in reinforcement learning by reusing the knowledge acquired from different but related source *** to the difference in state space and/or action space of the target and source task,transfer via inter-task mapping is a popular *** design of the inter-task mapping is very critical to this transfer learning *** this paper,we propose a linear multi-variable mapping（LMVM） for the transfer learning to make a better use of the knowledge learned from the source *** the inter-task mapping used before,the LMVM is not a one-to-one mapping but a one-to-many mapping,which is based on the idea that the element in target task is related with several similar elements from source *** test transfer learning via our new mapping on the Keepaway *** experimental results show that our method could make the reinforcement learning agents learn much faster than those without transfer and those transfer with simpler mappings.

关键词： Transfer Learning Reinforcement Learning Linear Multi-variable Mapping Inter-task Mapping Keepaway

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Journal of Mountain Science 2015年第3期12卷 699-710页

作者： WANG Jun YU Yan PAN Hua-li qiao cheng OU Guo-qiang Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences University of Chinese Academy of Sciences

Abstract： The Wenchuan earthquake generated strong surface disturbances and triggered a large number of loose deposits, resulting in the disaster- prone environment with special watershed hydrological characteristics. This paper was to propose a debris flow formation process and explore the permeability characteristics and critical hydrodynamic conditions of the loose deposits triggered by the earthquake. The Guo Juanyan gully （31005＇27＂ N to 31005＇46＂ N, 103036＇58＂ E to 103037＇09＂ E） in Du Jiangyan City, located in the meizoseismal areas of the Wenchuan earthquake, was chosen as the study area and the disaster-prone environment was analyzed. The formation process of the debris flow was first proposed using a stability analysis, and then, the permeability characteristics of loose deposits were determined via in situ permeability experiments. Finally, the critical 1 h rainfall was simulated through a distributed hydrological model and verified by field observations. The formation process of debris flow could be divided into three stages based on the relationship between the hydrodynamic force and loose deposit resistance. The critical 1 h rainfall amounts under three antecedent moisture conditions （I-dry, Ⅱ-normal and Ⅲ-wet） were 52 mm/h, 43 mm/h and 34 mm/h, respectively. This study proposed a debris flow formation process in the meizoseismal areas of the Wenchuan earthquake based on the stability analysis and defined the rainfall threshold for debris flow early warning at the local level, which is significant for debris flow mitigation and risk management.

关键词： Wenchuan Earthquake Debris flow Disaster-prone environment Permeabilitycharacteristics Hydrodynamic condition

Long runout mechanism of the Shenzhen 2015 landslide:insights from a two-phase flow viewpoint

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Journal of Mountain Science 2018年第10期15卷 2247-2265页

作者： qiao cheng OU Guo-qiang PAN Hua-li OUYANG Chao-jun JIA Yang Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Key Laboratory of Mountain Surface Process and Hazards Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China Anhui University of Science&Technology Huainan 232002China

A catastrophic landslide occurred at Hongao dumpsite in Guangming New District of Shenzhen, South China, on December 20, 2015. An estimated total volume of 2.73×106 m3 of construction spoils was mobilized during this event. The landslide traveled a long distance on a low-relief terrain. The affected area was approximately 1100 m in length and 630 m in width. This landslide made 33 buildings destroyed, 73 people died and 4 people lost. Due to the special dumping history and other factors, soil in this landfill is of high initial water content. To identify the major factors that attribute to the long runout character, a two-phase flow model of Iverson and George was used to simulate the dynamics of this landslide. The influence of initial hydraulic permeability, initial dilatancy, and earth pressure coefficient was examined through numerical simulations. We found that pore pressure has the most significant effect on the dynamic characteristics of Shenzhen landslides. Average pore pressure ratio ofthe whole basal surface was used to evaluate the degree of liquefaction for the sliding material. The evolution and influence factors of this ratio were analyzed based on the computational results. An exponential function was proposed to fit the evolution curve of the average pore pressure ratio, which can be used as a reasonable and simplified evaluation of the pore pressure. This fitting function can be utilized to improve the single-phase flow model.

关键词： Dynamics Landslide Long runout Pore pressure Two-phase

Determination of dynamic capillary effect on two-phase flow in porous media: A perspective from various methods

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Petroleum Science 2022年第4期19卷 1641-1652页

作者： Jian-Chao Cai Yin Chen Jun-cheng qiao Liu Yang Jian-Hui Zeng Chen-Hao Sun State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249PR China Institute of Geophysics and Geomatics China University of GeosciencesWuhan430074HubeiPR China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Bejing100083PR China

The relationship between capillary pressure and saturation plays a critical role in the characterization of two-phase flow and transport in aquifers and oil reservoirs. This relationship is usually determined under the static condition, where capillary pressure is the only function of saturation. However,considerable experiments have suggested that the dependence of capillary pressure on desaturation rate is under the dynamic condition. Thus, a more general description of capillary pressure that includes dynamic capillary effect has been approved widely. A comprehensive understanding of the dynamic capillary effect is needed for the investigation of the two-phase flow in porous media by various methods. In general, dynamic capillary effect in porous media can be studied through the laboratory experiment, pore-to macro-scale modeling, and artificial neural network. Here, main principle and research procedures of each method are reviewed in detail. Then, research progress, disadvantages and advantages are discussed, respectively. In addition, upscaling study from pore-to macro-scale are introduced, which explains the difference between laboratory experiment and pore-scale modeling. At last, several future perspectives and recommendations for optimal solution of dynamic capillary effect are presented.

关键词： Dynamic capillary effect Capillary pressure Two-phase flow Modeling method

Experimental Study of Wastewater Treatment of Reactive Dye by Phys-Chemistry Method

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Journal of China University of Mining and Technology 2007年第1期17卷 96-100页

作者： YANG Yan-wu ZHOU Tong-ling qiao Qi-cheng CHEN Shuo School of Environment ＆ Spatial lnformatics China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Lab and Equipment Administration Office China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Foreign Studies China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Wastewater, which involves easy-soluble reactive dyes, especially non-degradable dyes, is very difficult to decolor efficiently by normal processes such as coagulation process and biological treatment. The high chromaticity se- riously hinders the reuse of reactive dye waste water. In this paper, a new method by bentonite adsorption and coagulation (PAC) is employed for removing color from synthetic dye waste water which contains reactive red K-2G, K-RN blue, K-GR blue, X-3B red, K-GN orange, KB-3G yellow, K-2BP red, K-RN yellow and K-6G yellow. Bentonite pre- treated by 4% CTMAB and milled to 160 order screen is proven to the best decoloring agent. For a 100 mL reactive red K-2G sample (CODcr 400 mg/L, 25 000 chromaticity color), 0.5 g bentonite pretreated and 2.5 mL PAC is enough to decolor wastewater up to 99.92% and the sediment time is short. Non-degradable dyes such as active red X-3B and K-GN orange are declored completely as well. Raw sewage (low chromaticity color) is decolored completely at a ben-tonite dosage of 0.001g. More researches prove the high practical value of this process.

关键词： reactive dye wastewater pretreated bentonite chromaticity color waste water reuse

Iridoid glycosides from the roots of Scrophularia ningpoensis Hemsl

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Chinese Chemical Letters 2014年第10期25卷 1354-1356页

作者： Ling-Juan Zhu cheng qiao Xiu-Yu Shen Xue Zhang Xin-Sheng Yao College of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education Shenyang Pharmaceutical University Institute of Traditional Chinese Medicine & Natural Products College of PharmacyJinan University

Two new iridoid glycosides,named scrophularianoids A（1） and B（2）,were isolated from the roots of Scrophularia *** chemical structures were established on the basis of extensive analyses of spectroscopic *** 1 and ... 详细信息

关键词： Scrophularia ningpoensis lridoid glycosides Scrophularianoid A Scrophularianoid B