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Chinese Optics Letters 2024年第5期22卷 62-67页

作者：赵悦秦莹贾凯琳陈丽陈广伟胡国庆武腾飞李慧宇贺敬文周哲海 Key Laboratory of Modern Optoelectronic Measurement Technology in Mechanical Industry Beijing Information Science and Technology UniversityBeijing 100192China Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instruments Beijing Information Science and Technology UniversityBeijing 100192China Changcheng Institute of Metrology&Measurement Beijing 100095China national physical experiment teaching demonstration center Beijing Jiaotong UniversityBeijing 100044China

We experimentally demonstrate tunable dual-comb soliton rains in a polarization multiplexing fiber laser based on a singlewalled carbon *** repetition frequency difference of dual-comb pulses is about 39 Hz,with a maximum extinction ratio of 29 *** suitable polarization states,one of the dual-comb pulses switches into soliton rain sequence with chirped isolating soliton *** signal-to-noise ratio reaches 61 dB,which is 11 dB higher than that of the normal dual-comb *** intervals between chirped isolating solitons are distributed progressively,and the number of isolating solitons can be flexibly tuned from 2 to 11 by adjusting polarization state or pump *** work will provide support for further understanding of interaction dynamics of solitons and give a new route to the application of precision measurement.

关键词： mode-locked fiber laser soliton rains dual-comb pulses gain relaxation dynamics single-walled carbon nanotube

Towards accurate mapping of loess waterworn gully by integrating google earth imagery and DEM using deep learning

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International Soil and Water Conservation Research 2024年第1期12卷 13-28页

作者： Rong Chen Yi Zhou Zetao Wang Ying Li Fan Li Feng Yang School of Geography and Tourism Shaanxi Normal UniversityXi'an710119China national experiment and teaching demonstration center for Geography Xi'an710119China SuperMap Software Co. Ltd.Beijing100015China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen518055China

Accurate mapping of loess waterworn gully(LWG)is essential to further study gully erosion and geomorphological evolution for the Chinese Loess Plateau(CLP).Due to the vertical joint and collapsibility of loess,LWGs have the characteristics of zigzag and unique slope abruptness under synthetic action of hydraulic force and *** forces existing LWG mapping methods to either focus on the improvement of mapping accuracy or center on the increase of mapping ***,simultaneously achieving accurate and efficient mapping of LWG is still in its infancy under complex topographic ***,we proposed a method that innovatively integrates the loess slope abruptness feature into an improved deep learning semantic segmentation framework for LWG mapping using 0.6 m Google imagery and 5 m DEM *** selected four study areas representing typical loess landforms to test the performance of our *** proposed method can achieve satisfactory mapping results,with the F1 score,mean Intersection-over-Union(mIoU),and overall accuracy of 90.5%,85.3%,and 92.3%,*** addition,the proposed model also showed significant accuracy improvement by inputting additional topographic information(especially the slope of slope).Compared with existing algorithms(Random forests,original DeepLabV3+,and Unet),the proposed approach in this study achieved a better accuracy-efficiency ***,the method can ensure high accuracy and efficiency of the LWG mapping for different loess landform types and can be extended to study various loess gully mapping and water and soil conservation.

关键词： Loess waterworn gully Topographic information Mapping Deep learning Soil erosion Loess plateau

Construction of Molecular Biology and experiment Case Library for Graduate Students

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Asian Agricultural Research 2024年第8期16卷 47-49页

作者： Huanying PANG Miao XIE Shuanghu CAI Yu HUANG Yucong HUANG Jichang JIAN Fisheries College Guangdong Ocean UniversityZhanjiang 524088China national Fisheries Science and Technology experimental teaching demonstration center Zhanjiang 524088China

Molecular Biology and experiment is considered fundamental for graduate students specializing in aquaculture at Guangdong Ocean *** discipline focuses on the examination of the structure and function of macromolecules,including proteins and nucleic ***,it elucidates biological phenomena and principles at the molecular level,making it an essential foundational course for students pursuing various biology *** a foundational course for the basic application of aquaculture,Molecular Biology and experiment requires guidance through numerous examples and ***,there are several challenges to address in developing the case ***,a case library has been established to meet the course requirements of Molecular Biology and experiment for modern graduate students,with the central goal of reforming the educational model of higher education institutions and enhancing the effectiveness and quality of talent *** strategy is designed to nurture highly skilled professionals who can address the current needs of the industry.

关键词： Case library Molecular biology and experiment Aquaculture major

Friction of graphene on a substrate with a cavity defect

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Science China(Technological Sciences) 2024年第9期67卷 2834-2841页

作者： ZHOU Peng HUO ZhanLei CHANG TienChong Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringShanghai Frontier Science Center of MechanoinformaticsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China The center for Computational Mechanics and Engineering Applications Provincial Mechanics Experimental Teaching Demonstration CenterSchool of Civil EngineeringHebei University of EngineeringHandan 056038China Shanghai Institute of Aircraft Mechanics and Control Tongji UniversityShanghai 200092China Joint-Research center for Computational Materials Zhejiang LaboratoryHangzhou 311100China

The frictional behavior of supported graphene is known to be influenced by the physical properties and surface morphologies of the underlying substrate. However, it is unclear how a surface defect on the substrate affects the friction of supported graphene,and it is even unknown how to define the defect-induced friction force in this context. Here we conduct molecular dynamics(MD) simulations to investigate the friction between a square diamond slider and a graphene sheet supported by a copper substrate with a surface cavity defect. Our results demonstrate that the defect-induced friction exhibits a nonlinear increase with cavity size, while it decreases nonlinearly with slider size. We propose that the definition of defect-induced friction can be linked to the increase in friction work over the length of the slider, and is closely correlated to the defect-induced relative change in indentation depth and the ratio of the cavity area to the contact area. These findings provide a comprehensive evaluation of the impact of a substrate cavity defect on the friction of supported graphene and offer insights that may have broader implications for understanding defect-induced friction in other two-dimensional materials.

关键词： friction graphene underneath substrate cavity defect

Spatial distribution and influencing factors of Surface Nibble Degree index in the severe gully erosion region of China’s Loess Plateau

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Journal of Geographical Sciences 2021年第11期31卷 1575-1597页

作者： ZHOU Yi YANG Caiqin LI Fan CHEN Rong School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China national experiment and teaching demonstration center for Geography Xi'an 710119China

In China’s Loess Plateau severe gully erosion(LPGE)region,the shoulder-line is the most intuitive and unique manifestation of the loess landform,which divides a landform into positive and negative terrains(PNTs).The spatial combination model of PNTs is of great significance for revealing the evolution of the loess *** study modeled and proposed the Surface Nibble Degree(SND),which is a new index that reflects the comparison of the areas of *** on 5 m DEMs and matched high-resolution remote sensing images,the PNTs of 164 complete watersheds in the LPGE were extracted accurately,and the SND index was *** spatial distribution trend of SND was discussed,and the relationship between SND and the factors that affect the evolution mechanism of regional landform was explored *** show that:(1)The SND can be calculated *** can quantify the development of the loess landform well.(2)The SND of the LPGE has evident spatial differentiation that increases from southwest to *** values appear in Shenmu of Shaanxi,Shilou of Shanxi,and northern Yanhe River,whereas the low values are mainly distributed in the southern loess tableland and the inclined elongated ridge area of Pingliang in Gansu and Guyuan in Ningxia.(3)In the Wuding River and Yanhe River,the SND decreases with the increase in flow length(FL).In the North-Luohe River and Jinghe River,the SND increases with FL.(4)SND is significantly correlated with gully density and sediment modulus and moderately correlated with hypsometric *** for the mechanism factors analysis,the relationship between loess thickness and SND is not obvious,but SND increased first and then decreased with the increase of precipitation and vegetation in each geographical division,and we found that the land use type of low coverage grassland has greater erosion potential.

关键词： digital elevation model shoulder-line Surface Nibble Decree spatial distribution terrain factor digital terrain analysis Loess Plateau gully erosion region

Exploration and Realization of Several Key Problems of Geological Big Data

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Acta Geologica Sinica(English Edition) 2019年第S01期93卷 19-20页

作者： GUO Yanjun PAN Mao LIU Jianbo School of Earth and Space Science Peking UniversityBeijing 100871China national experiment and teaching demonstration center of Earth Science Peking UniversityBeijing 100871China national Virtual Simulation experiment teaching center of Earth Science Peking UniversityBeijing 100871China

With the rapid development of technology,geological big data is increasing explosively,and plays an increasingly important position in the national economy(Zhang and Zhou,2017;Zhou et al.,2018).Governments and agencies attach great importance to the open internet service of geological big data and information at home,and abroad(Yan et al.,2013;Guo et al.,2014).The basic norms of western countries’geological data information services are rich and varied products.

关键词： Geological big data 3D geological modelling virtual reality semantic ontology

Hollow and filled fiber bragg gratings in nano-bore optical fibers

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Chinese Physics B 2019年第7期28卷 279-285页

作者： Yong-Xin Zhang Sheng Liang Qian-Qing Yu Zheng-Gang Lian Zi-Nian Dong Xuan Wang Yu-Qin Lin Yu-Qi Zou Kun Xing Liu-Yan Liang Xiao-Ting Zhao Li-Jing Tu Key Laboratory of Education Ministry on Luminescence and Optical Information Technology National Physical Experiment Teaching Demonstration Center Department of Physics School of Science Beijing Jiaotong University Beijing 100044 China Yangtze Optical Electronic Company Ltd. Wuhan 430205 China Wuhan University of Technology Wuhan 430070 China Anhui Agricultural University Hefei 230036 China

To combine the technical functions and advantages of solid-core fiber Bragg gratings(FBGs) and hollow-core optical fibers(HCFs), the hollow and filled FBGs in nano-bore optical fibers(NBFs) with nano-bore in the GeO2-doped core are *** fundamental mode field, effective mode index, and confinement loss of NBF with 50 nm–7 μm-diameter hollow and filled nano-bore are numerically investigated by the finite element *** reflected spectra of FBGs in NBFs are obtained by the transmission matrix *** hollow FBGs in NBFs can be acheived with ~5% power fraction in the bore and the ~0.9 reflectivity when bore diameter is less than 3 μ*** filled FBGs can be realized with^1% power fraction and 0.98 reflectivity with different fillings including o-xylene, trichloroethylene, and chloroform for 800-nm bore *** feasibility of the index sensing by our proposed NBF FBG is also analyzed and *** experimental fabrication of hollow and filled FBGs are discussed and can be achieved by current *** aim of this work is to establish a principle prototype for investigating the HCFs and solid-core FBGs-based fiber-optic platforms,which are useful for applications such as the simultaneous chemical and physical sensing at the same position.

关键词： nano-bore optical fiber fiber Bragg grating(FBG) hollow-core optical fiber(HCF) fiber optics

Radiative cooling for passive thermal management towards sustainable carbon neutrality

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national Science Review 2023年第1期10卷 87-97页

作者： Jun Liang Jiawei Wu Jun Guo Huagen Li Xianjun Zhou Sheng Liang Cheng-Wei Qiu Guangming Tao Wuhan national Laboratory for Optoelectronics and Optics Valley Laboratory Huazhong University of Science and Technology Department of Electrical and Computer Engineering National University of Singapore MOE Key Laboratory of Thermo-Fluid Science and Engineering School of Energy and Power Engineering Xi'an Jiaotong University Key Laboratory of Education Ministry on Luminescence and Optical Information Technology National Physical Experiment Teaching Demonstration CenterDepartment of PhysicsSchool of Physical Science and Engineering Beijing Jiaotong University State Key Laboratory of Material Processing and Die &Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology

Photonic structures at the wavelength scale offer innovative energy solutions for a wide range of applications,from high-efficiency photovoltaics to passive cooling,thus reshaping the global energy *** cooling based on structural and material design presents new opportunities for sustainable carbon neutrality as a zero-energy,ecologically friendly cooling *** this review,in addition to introducing the fundamentals of the basic theory of radiative cooling technology,typical radiative cooling materials alongside their cooling effects over recent years are summarized and the current research status of radiative cooling materials is outlined and ***,technical challenges and potential advancements for radiative cooling are forecast with an outline of future application scenarios and development *** the future,radiative cooling is expected to make a significant contribution to global energy saving and emission reduction.

关键词： photonic structures radiative cooling energy saving and emission reduction carbon neutrality

Adsorption of congo red on mesoporous activated carbon prepared by CO2 physical activation

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Chinese Journal of Chemical Engineering 2020年第4期28卷 1069-1076页

作者： Mingjie Ma Huijuan Ying Fangfang Cao Qining Wang Ning Ai College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310014China Zhejiang Province Key Laboratory of Biomass Fuel Hangzhou 310014China Biodiesel Laboratory of China Petroleum and Chemical Industry Federation Hangzhou 310014China national Chemical and Chemical Engineer experiment teaching center National Chemical and Chemical Engineer Simulation Experiment Teaching CenterZhejiang University of TechnologyHangzhou 310014China

This research demonstrates the production of mesoporous activated carbon from sargassum fusiforme via physical activation with carbon *** composite design was applied to conduct the experiments at different levels by altering three operating *** temperature(766-934℃),CO2 flow rate(0.8-2.8 L·min^-1)and activation time(5-55 min)were the variables examined in this *** effect of parameters on the specific surface area,total pore volume and burn-out rate of activated carbon was studied,and the influential parameters of methylene blue adsorption value were identified employing analysis of *** optimum conditions for maximum methylene blue adsorption value were:activation temperature=900℃,activation time=29.05 min and CO2 flow rate=1.8 L·min(-1).The activated carbon produced under optimum conditions was characterized by BET,FTIR and *** adsorption behavior on congo red was *** effect of parameters on the adsorbent dosage,temperature,PH and initial congo red concentration was *** adsorption properties of the activated carbon were investigated by *** equilibrium removal rate and maximum adsorption capacity reaches up to 94.72%,234 mg·g^-1,respectively when initial congo red concentration is 200 mg·L^-1 under adsorbent dosage(0.8 g·L^-1),temperature(30℃),PH7.

关键词： Sargassum fusiforme Mesoporous activated carbon Congo red Response surface method Kinetics

Comparison of the Free Volume of LiCl-Added SPPO Membrane and SPPO-PES Blend Membrane by Positron Annihilation Method

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Plasma Science and Technology 2007年第5期9卷 575-577页

作者： Htwe Htwe YIN 黄环唐世彪马庆力 Department of Modern Physics University of Science and Technology of ChinaHefei 230026China center of physical experiment and teaching School of ScienceUniversity of Science and Technology of ChinaHefei 230026China Electronics Department Electronic Engineering InstituteHefei 230038China

Positron annihilation lifetime spectroscopy （PALS） is a powerful technique for the study of free volume in polymers. The lifetime of ortho-positronium （o-Ps）, a bound state of an electron and a positron, can be used to assess the pore size, while the intensity can be used to characterize the number of pores. Based on the values of the long-lived o-Ps components in the lifetime spectra, the radii and fractional free volumes of sulfonated poly （2,6-dimethyl-1,4- phenyleneoxide）（SPPO） membranes with added LiCl and SPPO-PES （Polyethersulfone） blend were compared. Free volume radii in both kinds of membranes are discussed.

关键词： positron annihilation free volume pore size SPPO polymer blend