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Integral precession calibration method of pIGA on linear vibration table

Chinese Journal of Aeronautics 2024年第3期37卷 219-236页

作者： Chuang sun Shun-qing rEN Jun-{1. CAO ru HUO Department of Automation Tsinghua UniversityBeijing 100084China School of Astronautics Harbin Institute of TechnologyHarbin 150001China beijing National research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China Faculty of Information technology Beijing University of TechnologyBeijing 100124China

Linear vibration table can provide harmonic accelerations to excite the nonlinear error terms of pendulous Integrating Gyro Accelerometer(pIGA).Integral precession calibration method is proposed to calibrate pIGA on a linear vibration table in this *** on the precise expressions of pIGA’s inputs,the error calibration model of pIGA is *** angular velocity errors of pIGA are suppressed by integer periodic precession and the errors caused by non-integer periods vibrating are *** complete calibration process,including planning,preparation,pIGA testing,and coefficient identification,is designed to optimize the test operations and evaluate the calibration *** effect of the main errors on calibration uncertainty is analyzed and the relative sensitivity function is proposed to further optimize the test *** and simulation results verify that the proposed 1.-position calibration method can improve calibration uncertainties after compensating for the related *** order of calibration uncertainties of the second-and third-order coefficients are decreased to 1.^(-8)(rad.s^(-1.)/g^(2.and 1.^(-8)(rad.s^(-1.)/g3,*** with the other two classical calibration methods,the calibration uncertainties of pIGA’s nonlinear error coefficients can be effectively reduced and the proportional residual errors are decreased less than 3×1.-6(rad.s^(-1.)/g by using the proposed calibration method.

关键词： pIGA Linear vibration table Vibration measurement Calibration Error analysis Uncertainty analysis

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research on the multi-level intake water temperature effect of the Yalong river Jinping-I hydropower project

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Science china(Technological {1.) 2011年第S1期54卷 125-132页

作者： WU ShiYong 1.CAO wei 1.WANG HongMei 1.{1. ShuangKe 2.&CHEN QiuWen 3 1.Ertan Hydropower Development Company,Ltd.,Chengdu 61.051.china 2.china institute of Water resources and Hydropower research,beijing 1.0038,china 3 research Center for Eco-Environmental sciences,Chinese academy of sciences,beijing 1.0085,china 1. Ertan Hydropower Development Company Ltd. Chengdu 610051 China2. China Institute of Water Resources and Hydropower Research Beijing 100038 China3. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Based on the discussion of the multi-level intake application status of high dam reservoir,this paper takes the Jinping-I hydropower project reservoir in the Yalong river as an example,which is shaped by the highest 305 m high arch dam,and carries out the forecasting research on the reservoir temperature by numerical simulation and physical model *** paper studies the intake effect of withdrawing the surface warm water by the stoplog gates inlets and verifies the reliability of the mathematical model by comparative *** results show that for a high dam hydropower station,taking the appropriate multi-level intake measure can withdraw the surface warm water in the spawning season and provide a favorable environment for the fish *** technical ideas and implementation scheme are adopted in this *** can provide technical reference for the solutions of similar problems in the future and it also has important engineering significance on the research of water temperature in large deep reservoirs.

关键词： water temperature multi-level intake Jinping-I hydropower project

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Experimental and numerical interpretation on composite foundation consisting of soil-cement column within warm and ice-rich frozen soil

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Journal of Mountain Science 2024年第1期21卷 313-321页

作者： WANG Honglei ZHANG Jianming wei Shoucai {1. Zhizhong ZHANG Hu School of Civil Engineering Hebei University of EngineeringHandan 056038China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Second Geological Brigade Bureau of Geology and Mineral Resources Exploration and DevelopmentLhasa 850000China Da Xing’anling Observation and research Station of Frozen Ground Engineering and Environment Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesJiagedaqi 165100China School of Civil Engineering Northeast Forestry UniversityHarbin 150040China

Affected by climate warming and anthropogenic disturbances, the thermo-mechanical stability of warm and ice-rich frozen ground along the Qinghai-Tibet engineering corridor(QTEC) is continuously decreased, which may delay the construction of major projects in the future. In this study, based on chemical stabilization of warm and icerich frozen ground, the soil-cement column(SCC) for ground improvement was recommended to reinforce the foundations in warm and ice-rich permafrost regions. To explore the validity of countermeasures mentioned above, both the original foundation and the composite foundation consisting of SCC with soil temperature of -1.0℃ were prepared in the laboratory, and then the plate loading tests were carried out. The laboratory investigations indicated that the bearing capacity of composite foundation consisting of SCC was higher than that of original foundation, and the total deformation of original foundation was greater than that of composite foundation, meaning that overall stability of foundation with warm and ice-rich frozen soil can be improved by SCC installation. Meanwhile, a numerical model considering the interface interaction between frozen soil and SCC was established for interpretating the bearing mechanism of composite foundation. The numerical investigations revealed that the SCC within composite foundation was responsible for the more applied load, and the applied load can be delivered to deeper zone in depth due to the SCC installation, which was favorable for improving the bearing characteristic of composite foundation. The investigations provide the valuable guideline for the choice of engineering supporting techniques to major projects within the QTEC.

关键词： Chemical stabilization Ground improvement Composite foundation Frozen soil engineering Qinghai-Tibet engineering corridor

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Atomically Dispersed Zinc Active Sites Efficiently promote the Electrochemical Conversion of N_(2. to NH_(3)

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Energy & Environmental Materials 2024年第3期7卷 175-181页

作者： Yanjiao wei Xinyu Wang Mengjie {1. Min Ma Jian Tian Minhua Shao School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong 999077China Energy institute and Chinese National Engineering Research Center for Control&Treatment of Heavy Metal PollutionThe Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong China

At present,the research on highly active and stable nitrogen reduction reaction catalysts is still challenging work for the electrosynthesis of ammonia(NH_(3)).Herein,we synthesized atomically dispersed zinc active sites supported on N-doped carbon nanosheets(Zn/NC NSs)as an efficient nitrogen reduction reaction catalyst,which achieves a high ammonia yield of 46.62.g h^(-1.mg^(-1._(cat).at-0.85 V(vs rHE)and Faradaic efficiency of 95.8%at-0.70 V(vs rHE).In addition,Zn/NC NSs present great stability and selectivity,and there is no significant change in NH_(3)rate and Faradaic efficiencies after multiple *** structural characterization shows that the active center in the nitrogen reduction reaction process is the Zn-N_(4)sites in the *** calculation confirms that Zn/NC with Zn-N_(4)configuration has a lower energy barrier for the formation of^(*)NNH intermediate compared with pure N-doped carbon nanosheets(N-C NSs),thus promoting the hydrogenation kinetics in the whole nitrogen reduction reaction process.

关键词： electrocatalysis nitrogen reduction single-atom catalyst Zn-N_(4)

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Free Vibration of Stiffened plate with Cracked Stiffeners

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Advances in applied Mathematics and Mechanics 2024年第1期16卷 253-278页

作者： Jian Xue Lihua Chen Yue sun {1. Zhang Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China Department of Mechanics School of ScienceHarbin Institute of TechnologyShenzhenGuangdong 518055China institute of Textiles and Clothing The Hong Kong Polytechnic UniversityHong KongChina

In this paper,a new cracked stiffener model for the stiffener with a partthrough and open crack is proposed,considering the compatibility condition of displacements between the plate and the *** on the first-order shear deformation theory,the free vibration of stiffened isotropic plates with cracked stiffeners are investigated for the first *** description of the crack parameters is based on the continuous equivalent bending stiffness and equivalent depth of the cracked beam,and it takes into consideration of shear deformation,bending-extensional coupling vibration,and eccentricity between the stiffeners and the *** stiffened plates with single or multiple cracked stiffeners are formulated and *** ritz method with the modified characteristic functions is applied to demonstrate the effects of crack parameters(crack depth and location)coupling with the position and number of the cracked stiffeners on the vibration frequencies and modes of the stiffened *** validity and accuracy of the present solutions are verified through convergence studies and compared with the finite element results.

关键词： Free vibration stiffened plate cracked stiffener model crack ritz method

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The Spatiotemporal Distribution Characteristics of Cloud Types and phases in the Arctic Based on CloudSat and CALIpSO Cloud Classification products

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Advances in Atmospheric sciences 2024年第2期41卷 310-324页

作者： Yue sun Huiling YANG Hui XIAO Liang FENG {1. CHENG Libo ZHOU {1.xi SHU Jingzhe sun Key Laboratory of Cloud-precipitation physics and Severe Storms(LACS) and Department of Lower Atmospheric Observation Research(LAOR)Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth sciences University of Chinese Academy of Sciences(UCAS)Beijing 100049China beijing {1. of {2. Meteorology Beijing 100029China

The cloud type product 2.-CLDCLASS-LIDAr based on CloudSat and CALIpSO from June 2.06 to May 2.1. is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud types(high cloud, altostratus, altocumulus, stratus, stratocumulus, cumulus, nimbostratus, and deep convection) and three phases(ice,mixed, and water) in the Arctic. possible reasons for the observed interannual variability are also discussed. The main conclusions are as follows:(1. More water clouds occur on the Atlantic side, and more ice clouds occur over continents.(2.The average spatial and seasonal distributions of cloud types show three patterns: high clouds and most cumuliform clouds are concentrated in low-latitude locations and peak in summer;altostratus and nimbostratus are concentrated over and around continents and are less abundant in summer;stratocumulus and stratus are concentrated near the inner Arctic and peak during spring and autumn.(3) regional averaged interannual frequencies of ice clouds and altostratus clouds significantly decrease, while those of water clouds, altocumulus, and cumulus clouds increase significantly.(4) Significant features of the linear trends of cloud frequencies are mainly located over ocean areas.(5) The monthly water cloud frequency anomalies are positively correlated with air temperature in most of the troposphere, while those for ice clouds are negatively correlated.(6) The decrease in altostratus clouds is associated with the weakening of the Arctic front due to Arctic warming, while increased water vapor transport into the Arctic and higher atmospheric instability lead to more cumulus and altocumulus clouds.

关键词： CloudSat and CALIpSO cloud type cloud phase temporal and spatial distribution interannual variation

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Arabian peninsula-North pacific Oscillation and its association with the Asian summer monsoon

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Science china Earth {1. 2008年第7期51卷 1001-1012页

作者： sun JianQi1. YUAN {1.2.& GAO YuZhong3 1.Nansen-Zhu International research Centre, institute of Atmospheric physics, Chinese academy of sciences, beijing 1.002., china 2.china Meteorological Administration Training Centre, beijing 1.0081. china 3 Heilongjiang Meteorological Observatory, Harbin 1.0030, china 1. Nansen-Zhu International research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. china Meteorological Administration Training Centre Beijing 100081 China 3. Heilongjiang Meteorological Observatory Harbin 150030 China

Using correlation and EOF analyses on sea level pressure from 57-year NCEp-NCAr reanalysis data, the Arabian peninsula-North pacific Oscillation (ApNpO) is identified. The ApNpO reflects the co-variability between the North pacific high and South Asian summer monsoon low. This teleconnec- tion pattern is closely related to the Asian summer monsoon. On interannual timescale, it co-varies with both the East Asian summer monsoon (EASM) and South Asian summer monsoon (SASM); on decadal timescale, it co-varies with the EASM: both exhibit two abrupt climate changes in the middle 1.60s and the late 1.70s respectively. The possible physical process for the connections between the ApNpO and Asian summer monsoon is then explored by analyzing the ApNpO-related atmospheric circulations. The results show that with a strong ApNpO, the Somali Jet, SASM flow, EASM flow, and South Asian high are all enhanced, and an anomalous anticyclone is produced at the upper level over northeast {2. via a zonal wave train. Meanwhile, the moisture transportation to the Asian monsoon regions is also strengthened in a strong ApNpO year, leading to a strong moisture convergence over India and northern {2.. All these changes of circulations and moisture conditions finally result in an anoma- lous Asian summer monsoon and monsoon rainfall over India and northern {2.. In addition, the ApNpO has a good persistence from spring to summer. The spring ApNpO is also significantly corre- lated with Asian summer monsoon variability. The spring ApNpO might therefore provide valuable in- formation for the prediction of Asian summer monsoon.

关键词： Arabian peninsula-North pacific Oscillation East Asian summer monsoon South Asian summer monsoon wave train abrupt climate change

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Cu single atoms embedded on hollow g-C_(3)N_(4)nanospheres with enhanced charge transfer and separation for efficient photocatalysis

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Chinese Chemical Letters 2024年第2期35卷 455-459页

作者： Linlin Zhang Jianjun Liao Yakun Li wei {1. Chengjun Ge Key Laboratory of Agro-Forestry Environmental processes and Ecological regulation of Hainan province School of Ecology and EnvironmentHainan UniversityHaikou 570228China Shandong Ocean Chemical Industry Scientific research institute Weifang 262737China

Establishing an effective charge transfer mechanism in carbon nitride(g-C_(3)N_(4))to enhance its photocatalytic activity remains a limiting ***,the combination design of a single Cu atom with hollow g-C_(3)N_(4)nanospheres(Cu-N_(3)structure)has been proven to offer significant opportunities for this crucial ***,this structure endows two pathways for charge transfer in the reaction,namely,the N atoms in the three-dimensional planar structure are only bonded with a single Cu atom,and charge transfer occurs between the plane and the layered structure due to the bending of the interlayered g-C_(3)N_(4)hollow ***,Cu-N_(3)and hollow nanosphere structures have been certified to greatly enhance the efficiency of photogenerated carrier separation and transfer between the layers and planes by ultrafast spectral *** a result,this catalyst possesses unparalleled photocatalytic ***,the hydrogen production rate up to 2.40μmol h^(−1. g^(−1.,which is 51.times that of pure C_(3)N_(4)under visible light *** photocatalytic degradation performance of tetracycline and oxidation performance of benzene is also expressed,with a degradation rate of 1.0%,a conversion of 97.3%and a selectivity of 99.9%.This work focuses on the structure-activity relationship to provide the possibilities for the development of potential photocatalytic materials.

关键词： g-C_(3)N_(4) Cu single atom Hollow nanospheres Charge transfer pathways photocatalytic hydrogen production

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A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic plateau

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Science china Earth {1. 2010年第5期53卷 763-772页

作者： CHEN BaiLian1.3, ZHANG renHe2. sun ShuFen1. BIAN LinGen2. XIAO CunDe4,2.& ZHANG TingJun5 1.{1. of Atmospheric physics, Chinese academy of sciences, beijing 1.002., china 2.Chinese academy of Meteorological sciences, beijing 1.0081. china 3 Graduate University of Chinese academy of sciences, beijing 1.0049, china 4 Cold and Arid regions Environmental and Engineering research {1., Chinese academy of sciences, Lanzhou 730000, china 5 The National Snow and Ice Data Center, University of Colorado, Boulder, CO 80309-0449, USA 1. institute of Atmospheric physics Chinese Academy of Sciences Beijing 100029 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Chinese Academy of Meteorological Sciences Beijing 100081 China4. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China5. The National Snow and Ice Data Center University of Colorado Boulder CO 80309-0449 USA

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°2.′S, 70°2.′E), we applied the model to simulate the seasonal temperature variation within a depth of 2. m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1. 1. 3, 1. m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1. the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2. the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model

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Environmental analysis of mercury in china

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Journal of Environmental sciences 2000年第S1期12卷 9-11页

作者： CHEN Jian\|hua 1. CHEN Le\|tian 1. LIN Yu\|huan 1. QI Xiao\|fan 1. SHI wei 2.(1. research Center for Eco\|Environmental {1., Chinese academy of {1., beijing 1.0085, china 2. {12. of applied Chemistry, Chinese academy of {1., C

This paper summarizes some of the research and evaluation about mercury analysis in environment during the past years in china. The main contents are as follows: determination of total mercury and speciation of mercury compounds in atmosphere;storage and treatment of mercury in water samples; pre\|treatment of solid samples; determination of total mercury and analysis of mercury species; certified reference materials.

关键词： analysis mercury china

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