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计算机教育 2021年第12期 166-172页

作者： Chunshan li dongmei li Dianhui Chu Hua Zhang the School of Computer Science Harbin Institute of TechnologyWeihai264209China the Network Center Shanxi Medical UniversityTaiyuanShanxi030607China

With the vigorous development of MOOC and SPOC,software engineering teachers are exploring how to use first-class online resources to reconstruct the software engineering teaching *** study proposed a project-driven group discussion classroom teaching reform,which is characterized by“the trinity integration of physical classroom,online classroom,and practical classroom”.The reform employs heuristic and case-based teaching methods,in which,the curriculum is supplemented by smart teaching tools and takes discussion teaching as the *** teaching process emphasizes the accumulation of multi-stage study results and adopts smart teaching method *** this study,we also build practical classrooms with top software *** encourage students to participate in the classroom and take the initiative to practice through“discussion groups”“enterprise practice”,and“cloud training”,which improves learning effectiveness and enhances the ability to analyze problems,design systems,and innovate in actual software projects.

关键词： blended teaching practice classroom group discussion MOOC SPOC

Sodium-doped carbon nitride nanotubes for efficient visible light-driven hydrogen production

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Nano Research 2018年第4期11卷 2295-2309页

作者： Longshuai Zhang Ning Ding Muneaki Hashimoto Koudai Iwasaki Noriyasu Chikamori Kazuya Nakata Yuzhuan Xu Jiangjian Shi Huijue Wu Yanhong Luo dongmei li Akira Fujishima Qingbo Meng Key Laboratory for Renewable Energy Chinese Academy of Sciences (CAS) Beijing Key Laboratory for New Energy Materials and Devices Beijing National Laboratory for Condensed Matter Physics Institute of Physics CAS Beijing 100190 China Photocatalysis International Research Center Research Institute for Science and Technology Tokyo University of Science 2641 Yamazaki Noda Chiba 278-0022 Japan School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049 China

Sodium-doped carbon nitride nanotubes （Nax-CNNTs） were prepared by a green and simple two-step method and applied in photocatalytic water splitting for the first time. Transmission electron microscopy （TEM） element mapping and X-ray photoelectron spectroscopy （XPS） measurements confirm that sodium was successfully introduced in the carbon nitride nanotubes （CNNTs）, and the intrinsic structure of graphitic carbon nitride （g-C3N4） was also maintained in the products. Moreover, the porous structure of the CNNTs leads to relatively large specific surface areas. Photocatalytic tests indicate that the porous tubular structure and Na＋ doping can synergistically enhance the hydrogen evolution rate under visible light （λ 〉 420 nm） irradiation in the presence of sacrificial agents, leading to a hydrogen evolution rate as high as 143 μmol·h-1 （20 mg catalyst）. Moreover, other alkali metal-doped CNNTs, such as lix-CNNTs and Kx-CNNTs, were tested; both materials were found to enhance the hydrogen evolution rate, but to a lower extent compared with the Nax-CNNTs. This highlights the general applicability of the present method to prepare alkali metal-doped CNNTs; a preliminary mechanism for the photocatalytic hydrogen evolution reaction in the Nax-CNNTs is also proposed.

关键词： graphitic carbon nitrides nanotubes alkali metal doping photocatalytic hydrogen production hydrothermal/thermopolymerization processes two-step synthesis

Mechanical Behavior of a Glass-fiber Reinforced Composite to Steel Joint for Ships

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Journal of Marine Science and Application 2015年第1期14卷 39-45页

作者： Xiaowen li Ping li Zhuang lin dongmei Yang College of Shipbuilding Engineering Harbin Engineering University Harbin 150001 China

The use of a glass-fiber reinforced composite in marine structures is becoming more common, particularly due to the potential weight savings. The mechanical response of the joint between a glass-fiber reinforced polymer （GRP） superstructure and a steel hull formed is examined and subsequently modified to improve performance through a combined program of modeling and testing. A finite-element model is developed to predict the response of the joint. The model takes into account the contact at the interface between different materials, progressive damage, large deformation theory, and a non-linear stress-strain relationship. To predict the progressive failure, the analysis combines Hashin failure criteria and maximum stress failure criteria. The results show stress response has a great influence on the strength and bearing of the joint. The Balsawood-steel interface is proved to be critical to the mechanical behavior of the joint. Good agreement between experimental results and numerical predictions is observed.

关键词： glass-fiber reinforced composite marine structure mechanical behavior steel joint finite-element model progressivefailure Hashin failure criteria

Impressive self-healing phenomenon of Cu_2ZnSn(S, Se)_4 solar cells

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Chinese Physics B 2018年第6期27卷 72-80页

作者： Qing Yu Jiangjian Shi Pengpeng Zhang linbao Guo Xue Min Yanhong Luo Huijue Wu dongmei li Qingbo Meng CAS Key Laboratory for Renewable Energy Beijing Key Laboratory for New Energy Materials and Devices Institute of PhysicsChinese Academy of Sciences（CAS）School of Physical Sciences University of Chinese Academy of Science

A study of the self-healing phenomenon of Cu2ZnSn（S, Se）4（CZTSSe） solar cells has shown more than 10% enhancement in cell performance after storage at room temperature for a week, with a significant improvement in the open-circuit photovoltage（V（oc）） and fill factor（F F）. In addition, up to 10.45% power conversion efficiency（PCE） has been *** obvious change in crystallinity, crystal phase, optical absorption or elemental distribution in the CZTSSe films was detected on examining the x-ray diffraction（XRD） pattern, Raman spectrum, ultraviolet-visible（UV-Vis）, and *** investigations on the charge carrier concentration, charge radiative recombination, and band structure suggest that the enhancement in PCE stems mainly from a reduction in deep defects of the CZTSSe semiconductor film.

关键词： Cu2ZnSn(SSe)4 defects reduction self-healing

Application of phenonaphthazine derivatives as hole-transporting materials for perovskite solar cells

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Journal of Energy Chemistry 2016年第4期25卷 702-708页

作者： Xueyuan liu Fei Zhang Xicheng liu Mengna Sun Shirong Wang dongmei li Qingbo Meng Xianggao li School of Chemical Engineering and Technology Tianjin University Collaborative Innovation Center of Chemical Science and Engineering Beijing Key Laboratory for New Energy Materials and Devices Key Laboratory for Renewable Energy (CAS) Institute of Physics Chinese Academy of Sciences

Two electron-rich, solution-processable phenonaphthazine derivatives, 5,12-bis(N-[4,4'-bis-(phenyl) aminophen-4 ''-yl]}-phenonaphthazine (BPZTPA) and 5,12-bis{N-[4,4'-bis(methoxy-phenyl)aminophen-4'-phenonaphthazine (MeO-BPZTPA) have been designed and employed in the fabrication of perovskite solar cells. BPZTPA and MeO-BPZTPA exhibit excellent thermal stabilities, hole mobilities (similar to 10(-4) cm(2)/(V.s)) and suitable HOMO levels (-5.34 and-5.29 eV, respectively) relative to the valence band of the CH3NH3PbI3 and Au work function, showing their potential as alternative hole-transporting materials (HTMs). Meanwhile, the corresponding mesoporous TiO2/CH3NH3PbI3/HTM/Au devices are investigated, and the best power conversion efficiency of 10.36% has been achieved for MeO-BPZTPA without using p-type dopant. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.

关键词： Perovskite solar cell Phenonaphthazine Hole-transporting material Triphenylamine derivatives

Co-Localization of Sampling and Sequencing for Zoonotic Pathogen Identification in the Field Monitoring Using Mobile Laboratories

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China CDC weekly 2022年第12期4卷 259-263,I0007页

作者： Xin Lu Yao Peng Yuanyuan Geng Hongqun Zhao Xiaona Shen dongmei li Zhenpeng li liang Lu Mengguang Fan Wenbin Xu Jin Wang lianxu Xia Zhongbing Zhang Biao Kan State Key Laboratory of Infectious Disease Prevention and Control BeijingChina/National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina General Center for Disease Control and Prevention of Inner Mongolia Autonomous Region Huhhot CityInner Mongolia Autonomous RegionChina Siziwang Banner Center for Disease Control and Prevention Huhhot CityInner Mongolia Autonomous RegionChina School of Public Health Shandong UniversityJinan CityShandong ProvinceChina

Introduction:Accurate etiological detection is needed to evaluate the risk of zoonotic *** next-generation sequencing(mNGS)can be used to monitor pathogens in animal species and identify potential zoonotic *** current sampling model for zoonotic pathogen monitoring in wild animals requires samples to be transferred from the field to a laboratory for further ***:We constructed a zoonotic pathogen survey model using a set of mobile ***:The monitoring in this study was preplanned to detect Yersinia pestis,but the mNGS unexpectedly identified Bartonella *** the rodent samples,thus exposing the threat of bartonellosis to humans in this *** co-localization of sampling and sequencing(CLOSS)model we tested required no long-distance transferring of samples and expands the regional coverage of zoonotic surveys by using a mobile ***:Using this mNGS technique will enable detection of more zoonotic pathogens beyond the preplanned monitoring *** may increase the surveillance efficiency compared with that of the previous workflow and expand the application of the mobile laboratories for infectious diseases identification and surveillance in the field.

关键词： enable transferred monitoring

Analysis of Factors Influencing the Growth of Export of Agricultural Products in Yunnan Province: An Empirical Study Based on CMS Model

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Asian Agricultural Research 2013年第8期5卷 18-22页

作者： dongmei li Jianxing LU Zhiwen XIAO Bo li Institute of Agricultural Economics and Information Yunnan Academy of Agricultural Sciences Tea Research Institute Chinese Academy of Agricultural Sciences

Yunnan Province is the bridgehead for the opening of the southwest region in China,and the economic frontier of China-ASEAN economic cooperation,where the export of agricultural products plays an important role in promoting the openness of the southwest region and strengthening China-ASEAN economic *** this paper,we use CMS model to analyze causes of the increase in the exports of agricultural products in Yunnan Province during the period *** is found that the expanded import scale of agricultural products in the world,improvement in the export competitiveness of products and the adaption of product export structure to the changes in the structure of world import demand,are the main factors responsible for increase in the exports of agricultural products in Yunnan *** recent years, the improvement of competitiveness of the export of agricultural products becomes a key factor for the growth of the export of agricultural products in Yunnan *** terms of the products classified,strong export competitiveness has promoted the export of plant products,such as beverages and tobacco,while weak export competitiveness and unreasonable export structure has impeded the export of animal products,plant and animal oil and fat products.

关键词： Agricultural products Growth causes CMS model Yunn

Optimization of SRAP-PCR Reaction System in Flax

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Journal of Northeast Agricultural University(English Edition) 2009年第2期16卷 17-22页

作者： li dongmei ZHOU Yadong LENG Chao SU Yu li Ming College of Agriculture Northeast Agricultural University Harbin 150030 China

Part of wild flax species and cultivated species were used as materials for optimizing SRAP-PCR reaction system, and concentration gradient test was made for all factors in order to select and establish the optimal program and system fitting for amplifying high diversity, good reproducible and clear bands. This program and system could well meet the requirement of flax SRAP and prove that SRAP marker was feasible for researching genetic polymorphism of flax.

关键词： flax SRAP-PCR optimization Mg^2+ concentration

Reconfiguring perovskite interface via R;NBr addition reaction toward efficient and stable FAPbI;-based solar cells

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Science China Chemistry 2022年

作者： Hongshi li Zhenghao liu Zijing Chen Shan Tan Wenyan Zhao Yiming li Jiangjian Shi Huijue Wu Yanhong Luo dongmei li Qingbo Meng Laboratory for Renewable Energy (CAS) Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences (CAS) Institute of New Energy Material Chemistry School of Materials Science and Engineering Nankai University School of Physical Sciences University of Chinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Songshan Lake Materials Laboratory Dongguan

Defect states in perovskite films restrict the interfacial stability and open-circuit voltage of perovskite solar cells. Here, aiming at superior interfacial passivation, we investigate the reconfiguration of perovskite interface by the interaction between a series of quaternary ammonium bromides （QAB） and lead–halide （Pb–X） octahedrons. Bromide–iodide substitution reaction or R;NBr addition reaction may occur on the perovskite surface, which is related to the steric hindrance of quaternary ammonium *** this basis, the perovskite surface morphology, band structure, growth orientation and defect states are reconstructed via the R;NBr addition reaction. This ordered lead–halide adduct could effectively repair the imperfect perovskite/hole transportation layer interface to suppress non-radiative recombination and ion migration toward ultralong carrier lifetime surpassing 10 μs. The resulting perovskite solar cells yield the efficiency of 23.89% with steady-state efficiency of 23.70%. The passivated cells can sustain 86% of initial efficiency after 200-h operation, which is attributed to the passivation effect and hydrophobic characteristics. This work provides an avenue for reconfiguring perovskite surface by QABs.

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The Study of Two Geomagnetic Jerks in China

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Earthquake Research in China 2009年第2期23卷 192-199页

作者： Zhang Suqin Yang dongmei li Qi Zhao Yongfen Institute of Geophysics China Earthquake Administration Beijing 100081 China

This paper analyzes the first differences of the annual means (annual rate) for the Y and Z components of the geomagnetic field from nine magnetic observatories in China, measured from 1985 to 2003. The 1991 jerk was obvious in the Y component measured but not clear for the Z component. Rapid changes in the Z components were ubiquitous around 2000-2001, but not seen for the Y component. External effects were removed from the monthly means by comparing the monthly mean of the geomagnetic field components at the observatories with the monthly time series of the A_p geomagnetic index. However, some examples were analyzed and showed whether external effects were removed or not, there was no marked distinction in determining the jerks in China for the Y component and the Z component of the geomagnetic field. Finally, the isolines of the first differences of the annual means were used to analyze the spatial and temporal distributions of the jerks.

关键词： Jerk Annual rate External field Isolines Ap index