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Early development,life history and ecological habits of Grateloupia constricata li et ding

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Acta Oceanologica Sinica 2020年第10期39卷 155-161页

作者： Yuanyuan ding Yao Bian Huina Wang Jing liu Jingrui li Hongwei Wang College of life Sciences Liaoning Normal UniversityDalian 116000China

As the largest genus of Halymeniaceae,Grateloupia has been widely ***,we observed the life history and early development of Grateloupia constricata li et ding and investigated the effects of temperature,irradiance,and photoperiod on the discoid crust and sporeling development of *** under laboratory *** observed that the type of carpospore development was“mediate discal type”.The life history included homotypic gametophyte(haploid),carposporophyte(diploid),and tetrasporophyte(diploid),with typical isomorphic alternation of *** results of double factorial analysis showed that both single factorial effects and interaction among temperature,photoperiod,and irradiance were obviously significant on the discoid crust and sporeling ***,we found that the optimum combination of condition for the early growth and development of *** was temperature 20°C,irradiance 80μmol photons/(m^2·s)and photoperiod 16L:*** study provides the theoretical basis and technical support for the conservation of the Grateloupia germplasm,artificial breeding,large-scale cultivation and sustainable development.

关键词： carpospore life history alternation of generations temperature irradiance photoperiod

Recent progress in the interaction between energetic particles and tearing modes

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National Science Review 2022年第11期9卷 240-261页

作者： Huishan Cai ding li Chinese Academy of Sciences Key Laboratory of Geospace Environment School of Nuclear Sciences and TechnologyUniversity of Science and Technology of China Institute of Physics Chinese Academy of Sciences Songshan Lake Materials Laboratory

The dynamics of energetic particles and tearing modes and the interactions between them are of great significance for magnetically confined fusion plasmas. In this review, we focus on these issues in the context of tokamak plasmas. The interaction between energetic particles and tearing modes is considered from two perspectives:(i) the influence of energetic particles on tearing modes and(ii) the transport of energetic particles by tearing modes. The influence of energetic particles on tearing modes is described on the basis of a general dispersion relation for tearing modes. The effects of energetic particles are considered separately in the outer region and the island region of a tearing mode. The physics mainly results from the modification of the perturbed parallel current by energetic particles without wave–particle resonance. In addition, the resonance between energetic particles and tearing modes is also reviewed. For the transport of energetic particles, transport of both circulating and trapped energetic particles by tearing mode is reviewed. Our descriptions of physical phenomena here are based on an analytical approach, while the experiments and simulations are used to illustrate and confirm our results. Finally, a number of open issues are discussed.

关键词： magnetically confined plasma energetic particle tearing mode transport confinement tokamak

The Adiabatic limit of Fu–Yau Equations

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Acta Mathematica Sinica,English Series 2022年第7期38卷 1255-1270页

作者： li ding HUANG School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026P.R.China

In this paper,we consider the adiabatic limit of Fu–Yau equations on a product of two Calabi–Yau *** prove that the adiabatic limit of Fu–Yau equations are quasilinear equations.

关键词： The Fu-Yau equation adiabatic limit Strominger system 2nd Hessian equation

VISCOUS FLOWS AROUND BODY-WING JUNCTURES

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Journal of Hydrodynamics 1993年第2期5卷 114-118页

作者： li, ding China Ship Scientific Research Cent Wuxi China

When an incoming boundary layer flow encounters the large pressure gradient in front of a protruded bluff body such as that of a wing/flat-plate juncture, a horseshoe vortex or a system of horseshoe vortices is generated. These horseshoe vortices travel downstream and form streamwise vortices in the wake. Such a flow phenomenon occurs in many practical applications such as the flow around wing/fuselage juncture of an aircraft, around appendage/hull junctures of a ships, around high-rise building, around bridge piers in rivers, and around blade passages in turbomachines. Due to the vortex flow generated at the juncture, the drag is in general increased and the heat transfer capacity is also degraded. For marine applications, there is an additional and perhaps more significant undesirable feature. That is the streamwise vortices in the wake cause the inflow to the propulsor system to become highly non-uniform. As a consequence, significant unsteady forces may result as the propeller is in operation. The purpose of this paper is to develop an integrated approach of experimentation, numerical evaluation and computer flow simulation for studying and control of the complex three-dimensional vortex flow in this matter.

关键词： Boundary layer flow Computer simulation Drag Fuselages Heat transfer Mathematical models Pressure effects Vortex flow Wakes Wings

Observed Trends in Various Aspects of Compound Heat Waves across China from 1961 to 2015

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Journal of Meteorological Research 2017年第3期31卷 455-467页

作者： Yi li Yihui ding Weijing li Chinese Academy of Meteorological Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology Laboratory for Climate Studies National Climate Center

Based on combined thresholds of daily maximum and minimum temperatures, a compound heat wave is defined, and then changes in multiple aspects of such heat waves in China are estimated between 1961 and 2015. Our results intriguingly indicate that severe compound heat waves in northern China are characterized by excessively high in- tensity within short duration, while long duration determines great disaster-causing potential of severe events in the south. In the past few decades, large areas of China have experienced longer, stronger, and more frequent compound heat waves. Northern China has witnessed dramatic intensity increases, with a maximum amplification over 5~C dec- ade-~; while remarkable lengthening in duration has been mostly recorded in the south, with a maximum trend over 1 day decade-1. The spatial extent affected by compound heat waves has significantly expanded since the 1960s, with the largest expanding rate over 6% decade-1 detected in North China and Northeast China. These systematic assess- ments serve to deepen our understanding of observed changes in compound heat waves across China, and may fur- ther shed some light on future adaptations and mitigations against an increasingly wanning climate.

关键词： heat wave climate change duration intensity spatial extent

Impacts of topographic factors on regional snow cover characteristics

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Water Science and Engineering 2020年第3期13卷 171-180页

作者： Muattar Saydi Jian-li ding College of Resources and Environmental Sciences Xinjiang UniversityUrumqi 830046China School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510275China Key Laboratory of Oasis Ecology Xinjiang UniversityUrumqi 830046China

At a local scale,snow cover is influenced by terrain properties,and it affects water availability across some arid and semiarid *** study aimed to quantify the spatial heterogeneity of snow cover due to topographic effects based on moderate-resolution image spectroradiometer(MODIS)daily snow cover products,processed with spatial and backward temporal filters.A snow-dominant region in the middle section of the northern Tianshan Mountains in China was selected,and the snow cover ratio(SCR)and the number of snow cover days(SCD)were *** results suggest that MODIS images are biased toward underestimation of the snow cover in the study region,and the error is primarily manifested within the elevation band of 1500e2500 *** snow cover is mainly affected by elevation,and snow mostly accumulates above 3800 *** addition,the differences in SCR and SCD between the south-and north-facing slopes are more significant than those between the east-and west-facing ***,the north-facing slopes have the maximum values of SCR and SCD,whereas the south-facing slopes have the minimum values of SCR and ***,the impact of slope gradients on snow cover varies across *** cover on a sloped surface decreases with the slope gradient during winter,while it tends to increase with the slope gradient during the other ***,this study presents a useful perspective on the variance in regional snow cover and provides guidance for the water resources management of snow meltwater with different terrain features.

关键词： Snow cover Snowmelt Surface runoff MODIS Topographic effect Elevation Aspect Tianshan Mountains

Stability Analysis of Distributed Parameter Systems on Temperature Measurement of Large-scale Objects

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Journal of Thermal Science 2007年第3期16卷 248-253页

作者： Zhenliang ding li ZHONG Feng YUAN Department of Electronic Engineering School of Automatic Measurement and Control Harbin Institute of Technology 150001 Harbin China

In this paper, the mechanical construction, thermal regulator design and temperature measurement system of a local area were set up for large-scale linear measurement. Numerical analysis based on temperature correlated characteristic is discussed to obtain optimal observation points for the measurements. The horizontal temperature distribution of the measured area is compared with the measurement of the variation of temperature at 15℃ and 20℃ over time, and characteristic of dynamic response is also discussed. In addition, the long-time stability of measured temperature is analyzed by means of using the standard deviation. It characterizes the temperature distribution performance of a large area and how it may impact the measurement of a large-scale object.

关键词： temperature control temperature measurement distribution parameter linear measurement.

Improved Methods for Acoustic Transmission along the Drill String and Other Periodic Media

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稀有金属材料与工程 2006年第A03期35卷 495-498页

作者： Cheng li Tianhuai ding Dept. of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

Acoustic telemetry along the drill string helps to know the physical and chemical characteristics of the formation and drilling fluid.A time-domain algorithm is developed for the propagation of one-dimensional axial stress waves with the inner and outer viscous *** algorithm simulates the passbands,stopbands and spikes due to the presence of the discontinuous boundaries of drill *** the effects of transmitted pulses and transceivers on acoustic transmission are *** simulated results show that the raised cosine pulses and optimal placements of transceivers improve system ***,dual PZT receivers can exclude signals propagating in a direction opposite to the transmitted signals. It is obvious that the uses of the available modeling and signal processing techniques can make the drill string as a waveguide for transmitting information at high data rates.

关键词： formation characteristics drill string acoustic telemetry well logging signal processing

The Cultural Connotation Study of National Central City

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学术界 2017年第12期 293-300页

作者： ding li College of Foreign Languages Zhengzhou Institute of Technology

National central city refers to the modern metropolis,which is located in the strategic position of the country,undertakes the national mission, leads the regional development,participates in international competition and represents the national image. Under the background of China’s new normal economy,the national central city will have a more profound cultural connotation than in the past.

关键词： national central city cultural connotation study