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Effect of geomorphologic features and climate change on vegetation distribution in the arid hot valleys of Jinsha River,Southwest China

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Journal of Mountain Science 2022年第10期19卷 2874-2885页

作者： ZHOU Yang YI yu-jun LIU Hong-xi TANG Cai-hong zhu yu-long ZHANG Shang-hong School of Water Resources and Hydropower Engineering North China Electric Power UniversityBeijing 102206China State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBejing 100875China Advanced Institute of Natural Sciences Beijing Normal UniversityZhuhai 519087China

Rapid change of climate in vertical and considerable geomorphologic features form a typical diversity and distribution of biota in mountain ecosystems,i.e.,the subalpine forest zone(SFZ),the valley savanna zone(VSZ),and the transition zone between *** arid hot valley in the middle and lower reaches of Jinsha River,China represents a well target area to study distribution and the driving factors in these typical mountain ***,this study selects four sub-sample areas in the arid-hot valley to explore the distinctive changes of vegetation during 1990 to 2020,and their driving factors in the three different vegetation zones on spatiotemporal *** the spatial scale,the Moran’s index was applied to identify the transition zone between the SFZ and the *** show that the VSZ at low altitudes(less than 600-1000 m from the valley bottom)is mainly affected by geomorphologic features,especially the slope *** increase in altitude,the climate factors(e.g.,humidity,temperature,etc.)play a more significant role in the development of the SFZ,while the effect of geomorphologic features gradually *** the time scale,The SFZ at higher altitudes experienced more rapid changes in temperature(temperature increase of 1.41°C over the last 60 years)than the VSZ at lower altitudes(temperature increase of 0.172°C over the past 60 years).It caused the forest cover increase faster than that of savanna *** and heat conditions are altered by topography and climate conditions,which shapes the development and physiology of plants as they adapt to the different climatic ***,according to the driving factors(geomorphologic and climate factors)of vegetation distribution found in this study,it suggests that suitable tree species should be planted in the transition zone to evolve into the forest zone and making the forest zone to recover from high to low altitudes gradually.

关键词： Mountain vegetation distribution Subalpine forest zone Valley savanna zone Geomorphologic features Climate change

Two new phenylpropanoid glycosides from Sanguisorba officinalis

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Chinese Chemical Letters 2012年第11期23卷 1243-1246页

作者： Jiang Hu Xiao Dong Shi Xia Mao Wei Dong Lu Lei zhu long yu College of Biological Resources and Environment Science Qujing Normal University Qujing 655011 China

Two new phenylpropanoid glycosides, 9-O-[6-O-acetyl-β-D-glucopyranosyl]-4-hydroxycinnamic acid （1） and 8-O-β-D-glucopyranosyl-（R）-（＋）-3,4,8-trihydroxy methyl phenylpropionate （2） were isolated from the 80% EtOH extract of the roots of Sanguisorba officinalis. Their slructures were characterized by spectroscopic analysis and chemical method, including 1D NMR, 2D NMR, and HR-ESI-MS. Compounds 1 and 2 exhibited the moderate antimicrobial activities against all Gram-positive and Gram-negative bacteria tested.

关键词： Sanguisorba officinalis Rosaceae Phenylpropanoid glycosides NMR techniques

Effectiveness of urban distributed runoff model for discharge and water depth calculation in urban drainage pipe networks

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Journal of Hydrodynamics 2024年第3期36卷 582-591页

作者： Yang Zhou Yi-ling Leng Peng-yu Wang Shang-hong Zhang yu-long zhu yu-jun Yi School of Water Resources and Hydropower Engineering North China Electric Power UniversityBeijing102206China State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing100875China

Effective urban land-use re-planning and the strategic arrangement of drainage pipe networks can significantly enhance urban flood defense *** at reducing the potential risks of urban flooding,this paper presents a straightforward and efficient approach to an urban distributed runoff model(UDRM).The model is developed to quantify the discharge and water depth within urban drainage pipe networks under varying rainfall intensities and land-use *** Nash efficiency coefficient of UDRM exceeds 0.9,which indicates its high computational efficiency and potential benefit in predicting urban *** prediction of drainage conditions under both current and re-planned land-use types is achieved by adopting different flood recurrence *** findings reveal that the re-planned land-use strategies could effectively diminish flood risk upstream of the drainage pipe network across 20-year and 50-year flood recurrence ***,in the case of extreme rainfall events(a 100-year flood recurrence),the re-planned land-use approach fell short of fulfilling the requirements necessary for flood disaster *** these instances,the adoption of larger-diameter drainage pipes becomes an essential requisite to satisfy drainage ***,the proposed UDRM effectively combines land-use information with pipeline data to give practical suggestions for pipeline modification and land-use optimization to combat urban ***,this methodology warrants further promotion in the field of urban re-planning.

关键词： Stormwater runoff water depth urban distributed runoff model urban drainage pipe networks urban land-use re-planning

High spectral efficiency 4-mode 400-km transmission using hybrid probabilistically and geometrically shaped 128QAM

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Science China(Technological Sciences) 2024年第5期67卷 1628-1630页

作者： DING JunJie yu JianJun WANG Chen long Jianyu zhu Min ZHANG Jiao Pervasive Communication Research Center Purple Mountain LaboratoriesNanjing 211111China Key Laboratory for Information Science of Electromagnetic Waves(MoE) Fudan UniversityShanghai 200433China

Wavelength division multiplexing(WDM)and space division multiplexing(SDM)based on few-mode fiber(FMF)and multi-core fiber(MCF)have been vigorously developed to increase the transmission capacity of optical communication networks[1–5].However,the mode crosstalk generated in the mode division multiplexing(MDM)system causes the correlation between different mode signals,which seriously damages the transmission ***,an effective multiple-input-multiple-output(MIMO)time domain or frequency domain equalizer should be used to eliminate the crosstalk between different mode signals.

关键词： crosstalk fiber multiplexing

Sustainable all-weather CO2 utilization by mimicking natural photosynthesis in a single material

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National Science Review 2024年第2期11卷 177-187页

作者： Xianjin Shi yu Huang Ran long Zhenyu Wang Liqin Wang Junji Cao Gangqiang zhu yujie Xiong State Key Laboratory of Loess and Quaternary Geology(SKLLQG) Key Laboratory of Aerosol Chemistry and Physics Institute of Earth EnvironmentChinese Academy of Sciences Center of Excellence in Quaternary Science and Global Change Chinese Academy of Sciences University of Chinese Academy of Sciences Hefei National Research Center for Physical Sciences at the Microscale School of Chemistry and Materials Science and National Synchrotron Radiation Laboratory University of Science and Technology of China Institute of Atmospheric Physics Chinese Academy of Sciences School of Physics and Information Technology Shaanxi Normal University

Solar-driven CO2conversion into hydrocarbon fuels is a sustainable approach to synchronously alleviating the energy crisis and achieving net ***,the dependence of the conversion process on solar illumination hinders its practical application due to the intermittent availability of sunlight at night and on cloudy or rainy ***,we report a model material of Pt-loaded hexagonal tungsten trioxide（Pt/h-WO3） for decoupling light and dark reaction processes,demonstrating the sustainable CO2conversion under dark conditions for the first *** such a material system,hydrogen atoms can be produced by photocatalytic water splitting under solar illumination,stored together with electrons in the h-WO3through the transition of W6+to W5+and spontaneously released to trigger catalytic CO2reduction under dark ***,we demonstrate using natural light that CH4production can persist at night and on rainy days,proving the accomplishment of all-weather CO2conversion via a sustainable way.

关键词： sustainable CO2 utilization artificial photosynthesis all-weather application charge storage

Privacy-Preserving Federated Mobility Prediction with Compound Data and Model Perturbation Mechanism

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China Communications 2024年第3期21卷 160-173页

作者： long Qingyue Wang Huandong Chen Huiming Jin Depeng zhu Lin yu Li Li Yong Beijing National Research Center for Information Science and Technology(BNRist) Department of Electronic EngineeringTsinghua UniversityBeijing 100084China China Mobile Research Beijing 100032China

Human mobility prediction is important for many ***,training an accurate mobility prediction model requires a large scale of human trajectories,where privacy issues become an important *** rising federated learning provides us with a promising solution to this problem,which enables mobile devices to collaboratively learn a shared prediction model while keeping all the training data on the device,decoupling the ability to do machine learning from the need to store the data in the ***,existing federated learningbased methods either do not provide privacy guarantees or have vulnerability in terms of privacy *** this paper,we combine the techniques of data perturbation and model perturbation mechanisms and propose a privacy-preserving mobility prediction algorithm,where we add noise to the transmitted model and the raw data collaboratively to protect user privacy and keep the mobility prediction *** experimental results show that our proposed method significantly outperforms the existing stateof-the-art mobility prediction method in terms of defensive performance against practical attacks while having comparable mobility prediction performance,demonstrating its effectiveness.

关键词： federated learning mobility prediction privacy

Radiation Spectral Analysis of 3D Dust Molecular Clusters(PAHs)and Peptoids under Ionization and Electric Field in ISM

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Research in Astronomy and Astrophysics 2024年第1期24卷 70-77页

作者： Ruiqing Wu Chunhua zhu Guoliang Lü Xiaojiao Zhang Xizhen Lu Jinlong yu Wujin Chen Mengqiu long School of Physics and Electronics Central South UniversityChangsha 410083China School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China School of Microelectronics and Physics Hunan University of Technology and BusinessChangsha 410205China College of Mechanical and Electronic Engineering Tarim UniversityAlar 843300China School of Medicine Xinjiang Medical UniversityUrumqi 830011China

Polycyclic aromatic hydrocarbons(PAHs),PANHs,and peptoids dust spectral calculations from the interstellar medium(ISM)are important for dust observations and *** goal is to calculate the radiation spectrum of spherical PAHs dust clusters in a vacuum containing ionized and applied in the presence of an electric *** propose a new simple computational model to calculate the size of three-dimensional spherical dust clusters formed by different initial dust *** the Vienna Ab-initio Simulation Package code,the density functional theory with the generalized approximation was used to calculate the electron density gradient and obtain the radiation spectrum of *** the radius of spherical dust clusters is~[0.009-0.042]μm,the dust radiation spectrum agrees well with the Z=0.02 mMMP stellar spectra,and the PAHs radiation spectrum of NGC 4676 at wavelengths of(0-5]μm and(5-10]μm,*** the ionized state,the N-PAH,C_(10)H_(9)N,2(C_(4)H_(4))^(1+),and peptoids 4(CHON),(C_(8)H_(10)N_(2)O_(5))^(1+)dust clusters at 3.3μm,while the 2(C_(22)H_(21)N_(3)O_(2))^(1+),4(CHON)dust clusters at 5.2μm have obvious *** is a characteristic of part of PAHs and peptoids clusters radiation at the nearinfrared wavelength of 2μ***,especially after applying an electric field to the dust,the emission spectrum of the dust increases significantly in the radiation wavelength range[3-10]μ***,the dust clusters of PAHs,PANHs,and peptoids of the radius size~[0.009-0.042]μm are likely to exist in the ISM.

关键词： ISM:structure ISM:molecules radiation mechanisms:general (ISM:)dust extinction

高校体育术科教师对混合式教学接受度及其影响因素研究——基于TAM模型的视角

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哈尔滨体育学院学报 2024年第4期42卷 72-79页

作者：李双玲朱宝峰李建业孙莉莉单子然袁志刚朱玉龙哈尔滨体育学院黑龙江哈尔滨150008 哈尔滨工业大学体育部黑龙江哈尔滨150001 波兰格但斯克体育学院波兰滨海80-336

为研究高校体育术科教师对混合式教学接受度的影响因素,切实提高体育术科类课程的教学效率,本研究以五所高校体育术科类课程教师(共计242人)为调查对象,依据技术接受模型(ATM),深入研究影响高校体育术科教师的认知、易用性、个体化需求... 详细信息

为研究高校体育术科教师对混合式教学接受度的影响因素,切实提高体育术科类课程的教学效率,本研究以五所高校体育术科类课程教师(共计242人)为调查对象,依据技术接受模型(ATM),深入研究影响高校体育术科教师的认知、易用性、个体化需求、学习氛围、交互性、接受度六个维度。其中接受度是潜在变量,认知、易用性、个体化需求、学习氛围、交互性为观测变量,采用Likert五级评分法,结合体育术科类课程的特点形成各维度的最初指标和各题目共21项。研究表明:高校体育术科教师的认知、易用性、个体化需求、学习氛围、交互性与接受度呈现显著正向影响;其中混合式教学认知丰富的教师,影响程度较大的依次为学习氛围、交互性、个体化需求、易用性;而对于混合式教学认知缺乏的教师,易用性的影响程度最大,其他依次为个体化需求、交互性、学习氛围。建议提升高校体育术科教师的认知水平,技术平台应根据体育学科的教学特点,开发符合体育教学需求的技术平台,提升教师的工作效率和学生的学习体验,从而有效增强教师对混合式教学模式的接受度和满意度,促使其积极主动地参与混合式教学,营造良好的教学改革氛围,切实提高教学效果。

关键词：高校体育术科教师混合式教学接受度认知

Topological Stability and Entropy for Certain Set-valued Maps

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Acta Mathematica Sinica,English Series 2024年第4期40卷 962-984页

作者： yu ZHANG yu Jun zhu School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

In this paper,the dynamics(including shadowing property,expansiveness,topological stability and entropy)of several types of upper semi-continuous set-valued maps are mainly considered from differentiable dynamical systems points of *** is shown that(1)if f is a hyperbolic endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has theε-shadowing property,and moreover,if f is an expanding endomorphism then there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has the Lipschitz shadowing property;(2)when a set-valued map F is generated by finite expanding endomorphisms,it has the shadowing property,and moreover,if the collection of the generators has no coincidence point then F is expansive and hence is topologically stable;(3)if f is an expanding endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that h(F_(f,U,ε))=h(f);(4)when F is generated by finite expanding endomorphisms with no coincidence point,the entropy formula of F is ***,the dynamics of the set-valued maps based on discontinuous maps on the interval are also considered.

关键词： Set-valued map orbit space hyperbolic endomorphism perturbation shadowing expansiveness topological stability entropy