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Comparing the Upper Triassic Deep-sea Flysch of the Shannan Terrane with the Coeval Shallow Shelf Sediments of the Tethys Himalaya,Southern Tibet

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Acta Geologica Sinica(English Edition) 2021年第2期95卷 348-354页

作者： li Xianghui frank MATTERN School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China College of Science Earth Science DepartmentSultan Qaboos UniversityAl-KhodPO Box 36Sultanate of Oman

The provenance and paleogeography of the Upper Triassic deep-sea flysch Langjiexue Group(LG)of the Shannan Terrane in the northeastern Himalaya orogen,south of Yarlung Zangbo,have been disputed in recent years since its affinity to the Tethys Himalaya was suspected during the early 2000 *** on the earlier discoveries of the Upper Permian–Triassic basalts and mafic dykes from the LG and of coeval detrital zircons from the Qulonggongba Formation(QF)in shallow shelf sediments of the Tethys Himalaya,the previous viewpoints on the basin and tectonics of the LG have been recently *** compared the two units of the Upper Triassic,and our results reveal a number of differences,discrepancies,and inconsistencies in the debate,raising crucial questions on the postulation and provenance model of the remote Gondwanide Orogen for the *** is suggested that more observations and evidence are needed to further improve the paleogeographic understanding and relationship of the two units.

关键词： sedimentology paleogeography flysch shelf sediment Late Triassic Shannan Terrane Tethys Tibet

Load-sharing mechanism in timber-steel hybrid shear wall systems

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Frontiers of Structural and Civil Engineering 2015年第2期9卷 203-214页

作者： Zheng li Minjuan HE frank LAM Minghao li Department of Structural Engineering Tongji University Shanghai 200092 China Department of Wood Science University of British Columbia Vancouver V6T 1Z4 Canada Department of Civil & Natural Resources Engineering University of Canterbury Christchurch New Zealand

The lateral performance of timber-steel hybrid shear wall systems with regard to the interaction between the steel frame and the infill wood shear wall was investigated in this paper. A numerical model for the timber-steel hybrid shear wall system was developed and verified against test results. Design parameters, such as the lateral infill-to-frame stiffness ratio and the arrangements of wood-steel bolted connections were studied using the numerical model. Some design recommendations were also proposed based on the parametric analysis. In the hybrid shear wall system, the infill wood wall was found to resist a major part of the lateral load within relatively small wall drifts, and then the steel frame provided more lateral resistance. Under seismic loads, the infill wood wall could significantly reduce the inter-story drift of the hybrid system, and a complementary effect between the infill wood wall and the steel frame was observed through different lateral load resisting mechanisms, which provided robustness to the hybrid shear wall systems.

关键词： timer-steel hybrid shear wall load sharing mechanism seismic performance parametric analysis

A Comprehensive Review of Redirected Walking Techniques:Taxonomy,Methods,and Future Directions

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Journal of Computer Science & Technology 2022年第3期37卷 561-583页

作者： Yi-Jun li frank Steinicke Miao Wang State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and EngineeringBeihang UniversityBeijing 100191China Department of Informatics Universität HamburgHamburg 20146Germany Peng Cheng Laboratory Shenzhen 518055China

Virtual reality(VR)allows users to explore and experience a computer-simulated virtual environment so that VR users can be immersed in a totally artificial virtual world and interact with arbitrary virtual ***,the limited physical tracking space usually restricts the exploration of large virtual spaces,and VR users have to use special locomotion techniques to move from one location to *** these techniques,redirected walking(RDW)is one of the most natural locomotion techniques to solve the problem based on near-natural walking *** core idea of the RDW technique is to imperceptibly guide users on virtual paths,which might vary from the paths they physically walk in the real *** a similar way,some RDW algorithms imperceptibly change the structure and layout of the virtual environment such that the virtual environment fits into the tracking *** this survey,we first present a taxonomy of existing RDW *** on this taxonomy,we compare and analyze both contributions and shortcomings of the existing methods in detail,and find view manipulation methods offer satisfactory visual effect but the experience can be interrupted when users reach the physical boundaries,while virtual environment manipulation methods can provide users with consistent movement but have limited application ***,we discuss possible future research directions,indicating combining artificial intelligence with this area will be effective and intriguing.

关键词： virtual reality locomotion redirected walking

Sprinkler rotation and water application rate for the newly-designed complete fluidic sprinkler and impact sprinkler

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International Journal of Agricultural and Biological Engineering 2014年第4期7卷 38-46页

作者： frank ADwomoh Yuan Shouqi li Hong Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang Jiangsu Province212013China School of Engineering Koforidua PolytechnicP.O.Box KF 981KoforiduaEastern RegionGhana

One important indicator of the good performance of rotating sprinklers is the uniformity of *** objective of this experimental study was to investigate the rotation uniformity and water application rate of the newly designed complete fluidic sprinkler in comparison to the widely used impact sprinkler,with the goal to offer recommendations to improve the fluidic sprinkler’s operation ***-sprinkler water application experiments were conducted in accordance with the American Society of Agricultural and Biological Engineers *** completion time through the four quadrants of rotation and water delivery in catch cans were measured at different operating pressures for each sprinkler-nozzle size *** capabilities of Matrix Laboratory were employed to simulate the overlap of adjacent quadrants and to visualize the effect of sprinkler rotation speed variation on water application *** completion time variations were small for both impact and fluidic ***,variations in completion time through the quadrants were higher for the fluidic sprinkler compared to the impact *** higher variations in water application rates were also observed for the fluidic *** optimization of the design features of the fluidic component is necessary to improve rotation stability and to minimize variability in water application rate of the fluidic *** study significantly highlighted some performance qualities of the complete fluidic sprinkler in comparison to that of the impact *** findings of this research will help to improve the efficiency of the new type complete fluidic sprinkler.

关键词： sprinkler rotation variation water application rate complete fluidic sprinkler impact sprinkler rotation uniformity

Perovskite–A wonder catalyst for solar hydrogen production

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Journal of Energy Chemistry 2021年第6期30卷 325-340,I0008页

作者： Hui Bian Deng li Junqing Yan Shengzhong(frank)liu Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationChina Shaanxi Engineering Lab for Advanced Energy Technology School of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119ShaanxiChina Dalian National Laboratory for Clean Energy China iChEM Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Hydrogen generation via artificial photosynthesis paves a promising way to remit the ever-increasing energy crisis and deteriorative environmental *** all the materials utilized for solar hydrogen production,perovskite has emerged as a rising star due to its superior optoelectronic *** manuscript aims to provide a comprehensive review summarizing the recent inspiring advancements on perovskite-based solar hydrogen production systems,including the particulate photocatalysis,photoelectrochemical cells,and photovoltaic-electrocatalytic *** start with a brief introduction of the advantages of perovskites for solar hydrogen production and the basic principles of the three most prominent solar hydrogen production *** representative progresses in this field are then detailed with a special emphasis on the strategies to improve the efficiency and the stability of the ***,challenges and opportunities for the further development of the PVK-based solar hydrogen production systems are presented with perspective given on outlook,performance,cost and stability.

关键词： Perovskite Solar hydrogen production Photocatalysis Photoelectrocatalysis Photovoltaic-electrocatalysis

Reinforcement learning for optimal tracking of large-scale systems with multitime scales

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Science China(Information Sciences) 2023年第7期66卷 5-29页

作者： Jinna li Hao NIE Tianyou CHAI frank L.LEWIS School of Information and Control Engineering Liaoning Petrochemical University State Key Laboratory of Synthetical Automation for Process Industries Northeastern University UTA Research Institute University of Texas at Arlington

This paper aims to solve an optimal tracking control(OTC) problem of large-scale systems with multitime scales and coupled subsystems using singular perturbation(SP) theory and reinforcement learning(RL) techniques. A considerable contribution of this paper is the development of a data-driven SP-based RL method for the OTC of unknown large-scale systems with multitime scales. To achieve this, a multitime scale tracking problem was decomposed into a linear quadratic tracker problem for slow subsystems and a dynamical game problem for fast subsystems using the SP theory. Then, the distributed composite feedback controllers were found using a distributed off-policy integral RL algorithm that uses only measured data from the system in real time. Thus, the operational index can follow its prescribed target value via an approximately optimal approach. Theoretical analysis and proof are presented to demonstrate that the sum of the performances of reduced-order subsystems is approximately equal to the performance of the original large-scale system. Finally, numerical and practical examples are provided to validate the effectiveness of the proposed method.

关键词： reinforcement learning singular perturbation multitime scales data-driven control

Photosynthesis and metabolite responses of Isatis indigotica Fortune to elevated [CO2]

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The Crop Journal 2017年第4期5卷 345-353页

作者： Ping li Hongying li Yuzheng Zong frank Yonghong li Yuanhuai Han Xingyu Hao College of Agriculture Shanxi Agricultural University Taigu 030801 Shanxi China Key Laboratory of Loess Plateau Crop Gene Resources and Germplasm Ministry of Agriculture Taiyuan 030001 Shanxi China Shanxi Key Laboratory of Genetic Resources and Genetic Improvement of Minor Crops Taigu 030801 Shanxi China

Climate change is affecting global crop productivity, food quality, and security. However,few studies have addressed the mechanism by which elevated CO_2 may affect the growth of medicinal plants. Isatis indigotica Fortune is a widely used Chinese medicinal herb with multiple pharmacological properties. To investigate the physiological mechanism of *** response to elevated [CO_2], plants were grown at either ambient [CO_2](385 μmol mol^(-1)) or elevated [CO_2] (590 μmol mol^(-1)) in an open-top chamber (OTC)experimental facility in North China. A significant reduction in transpiration rate (T_r) and stomatal conductance (g_s) and a large increase in water-use efficiency contributed to an increase in net photosynthetic rate (Pn) under elevated [CO_2] 76 days after sowing. Leaf non-photochemical quenching (NPQ) was decreased, so that more energy was used in effective quantum yield of PSII photochemistry (Φ_(PSⅡ)) under elevated [CO_2]. High ΦPSII,meaning high electron transfer efficiency, also increased Pn. The [CO_2]-induced increase in photosynthesis significantly increased biomass by 36.8%. Amounts of metabolic compounds involved in sucrose metabolism, pyrimidine metabolism, flavonoid biosynthesis, and other processes in leaves were reduced under elevated [CO_2]. These results showed that the fertilization effect of elevated [CO_2] is conducive to increasing dry weight but not secondary metabolism in I. indigotica.

关键词： Isatis indigotica Fortune Elevated [CO2] Biomass Photosynthesis Metabolites

Room-temperature sputtered-SnO_(2) modified anode toward efficient TiO_(2)-based planar perovskite solar cells

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Science China(Technological Sciences) 2021年第9期64卷 1995-2002页

作者： li Dan li Yong liU ZhiKe WANG DaPeng liU ShengZhong(frank) Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationShaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119China

It is of the utmost importance to promote the charge transport and retard the heterojunction barrier in the functional layers and at their adjacent interfaces to pursuit excellent photovoltaic characteristics of the perovskite solar cells(PSCs). Here, roomtemperature sputtered-SnO_(2) films are introduced to modify FTO anode for improving carrier extraction and aligning energy band in the TiO_(2)-based planar PSCs. For the SnO_(2)-modified substrate with suitable sputtering duration, the following TiO_(2) film exhibits smoother surface roughness, less surface defects, and lower the trap-assisted interfacial recombination than that directly on the FTO, further facilitating the growth of perovskite grain size and promoting the extraction efficiency of charge carriers. On the basis of the optimized SnO_(2)(6 nm)/TiO_(2) stack layer as electron transport layer(ETL), the PSC exhibits an outstanding power conversion efficiency of 21.45%, which is much better than that of the single TiO_(2)-based device(19.68%). More importantly, the cell with the bilayer ETL shows a long-term stability against air, maintaining over 76% of its initial efficiency after 40 d. These achievements suggest that this study provides a feasible path to design energy level alignment and low temperature ETL for highly efficient and stable PSCs.

关键词： sputtered-SnO_(2) anode modification bilayer ETL TiO_(2) PSC device

Effect of C/N ratio,aeration rate and moisture content on ammonia and greenhouse gas emission during the composting

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Journal of Environmental Sciences 2011年第10期23卷 1754-1760页

作者： Tao Jiang frank Schuchardt Guoxue li Rui Guo Yuanqiu Zhao College of Resources and Environment Sciences China Agricultural University Beijing 100094 China Johann Heinrich von Thuenen-lnstitute Institute of Agricultural Technology and Biosystems Engineering Bundesallee 50 38116 Braunschweig Germany College of Chemistry and Biology Leshan Normal College Leshan 614004 China

Gaseous emission （N2O, CH4 and NH3） from composting can be an important source of anthropogenic greenhouse gas and air pollution. A laboratory scale orthogonal experiment was conducted to estimate the effects of C/N ratio, aeration rate and initial moisture content on gaseous emission during the composting of pig faeces from Chinese Ganqinfen system. The results showed that about 23.9% to 45.6% of total organic carbon （TOC） was lost in the form of CO2 and 0.8% to 7.5% of TOC emitted as CH4. Most of the nitrogen was lost in the form of NH3, which account for 9.6% to 32.4% of initial nitrogen. N20 was also an important way of nitrogen losses and 1.5% to 7.3% of initial total nitrogen was lost as it. Statistic analysis showed that the aeration rate is the most important factor which could affect the NH3 （p = 0.0189）, CH4 （p = 0.0113） and N20 （p = 0.0493） emissions significantly. Higher aeration rates reduce the CH4 emission but increase the NH3 and N20 losses. C/N ratio could affect the NH3 （p = 0.0442） and CH4 （p = 0.0246） emissions significantly, but not the N20. Lower C/N ratio caused higher NH3 and CH4 emissions. The initial moisture content can not influence the gaseous emission significantly. Most treatments were matured after 37 days, except a trial with high moisture content and a low C/N ratio.

关键词： pig faeces composting methane nitrous oxide ammonia