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The gravitational gradient tensor’s invariants and the related boundary conditions

science china earth sciences 2010年第5期53卷 781-790页

作者： yu jinhai1,2,3 & zhao dongming4 1 college of earth science, graduate university of chinese academy of sciences, beijing 100049, china 2 Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 430077, china 3 State Key Laboratory of Astronautic Dynamics, Xi’an 710043, china 4 Zhengzhou Institute of Surveying and Mapping, Zhengzhou 450052, china college of earth science Graduate University of Chinese Academy of Sciences Beijing China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China State Key Laboratory of Astronautic Dynamics Xi’an China Zhengzhou Institute of Surveying and Mapping Zhengzhou China

Here we report new approaches of recovering the earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2-term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2/2 T), which is approximately equivalent to O(T2). Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 200, and the models with regard to effect of J2-term have accuracies of 10-8 and the order can reach up to 280.

关键词： the earth’s gravitational field gravitational gravidiometry tensor’s invariant

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Landscape Changes from 1974 to 1995 in the Upper Minjiang River Basin, china

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Pedosphere 2006年第3期16卷 398-405页

作者： HE Xing-yuan zhao Yong-Hua HU yuan-Man CHANG yu ZHOU Qi-Xing Institute of Applied Ecology the Chinese Academy of Sciences Shenyang 110016 （China） college of earth science ＆ Land Resources Management Chang＇an University Xi＇an 710054 （China） graduate School of the chinese academy of sciences Beijing 100039 （China）

Landscape changes were traced over the 20 years from 1974 to 1995 in the upper Minjiang River basin, one of the most important forest regions in china, based on satellite image interpretation to provide basic data for local decision-making as well as sustainable landscape use and management. Results revealed that landscape from 1974 to 1995 changed at the regional scale as the area of forestland decreased, while cropland, shrubland, economic forest, grassland, and built-up land increased. Landscape changes mainly occurred in forestland, shrubland, grassland, economic forest, and built-up land. Moreover, the changes among forestland, shrubland, and grassland were the largest, influencing the whole characteristics of the changes in the basin. Analysis of the changes between 1974 and 1995 in the study area indicated that landscape heterogeneity and fragmentation increased, whereas landscape connectivity decreased. There were multiple reasons for landscape changes. A principal component analysis (PCA) was used to quantitatively study driving forces of landscape changes. The PCA results showed that economic and population factors were the principal driving forces of landscape changes from 1974 to 1995 in the upper Minjiang River basin, and that PCA was a suitable method for investigating driving forces of landscape changes.

关键词： driving forces landscape change satellite image quantification principal component analysis

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Experimental constraints on the formation of oxychlorine species by UV irradiation and mechanical pulverization on the lunar surface

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Acta Geochimica 2024年第4期43卷 625-637页

作者： Jiamei Li yu-Yan Sara zhao He Cui Shuai-Yi Qu Yanhua Peng yuhong Yang Xiongyao Li Research Center for Planetary science College of Earth and Planetary SciencesChengdu University of TechnologyChengdu 610059China Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei 230026China college of Life sciences Wuchang University of TechnologyWuhan 430204China Technical Center of Qingdao Customs Qingdao 266114China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China university of chinese academy of sciences Beijing 100049China Nanning college of Technology Guilin 541006China Center for Lunar and Planetary sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

Perchlorate and chlorate are present in various extraterrestrial celestial bodies throughout the solar system,such as Mars,the moon,and *** date,the origin mechanisms of perchlorate and chlorate on the Martian surface have been well-established;however,relatively little attention has been cast to airless ***,we experimentally investigated the potential oxidation mechanisms of chloride to chlorate and perchlorate,such as ultraviolet irradiation under H_(2)O-and O_(2)-free conditions and mechanical pulverization *** minerals,olivine,pyroxene,ilmenite,magnetite,TiO_(2)and anhydrous ferric sulfate,and lunar regolith simulants(low Ti,CLRS-1;high-Ti,CLRS-2)and their metallic iron(Fe^( 0))bearing counterparts were *** found that pulverization of dry matrix material-halite mixtures,even in the presence of O_(2),does not necessarily lead to perchlorate and chlorate formation without involving *** photocatalytic and H_(2)O and O_(2)-free conditions,olivine and pyroxene can produce oxychlorine(ClO_(x)^(−))species,although the yields were orders of magnitude lower than those under Martian-relevant ***-Fe^(0)particles in the lunar regolith and the common photocatalyst TiO_(2)can facilitate the ClO_(x)^(−)formation,but their yields were lower than those with *** oxides ilmenite and magnetite did not efficiently contribute to ClO_(x)^(−)*** results highlight the critical role of H_(2)O in the oxidation chloride to chlorate and perchlorate,and provide essential insights into the environmental influence on the formation of oxychlorine species on different celestial bodies.

关键词： Perchlorate Chlorate Lunar regolith Metallic Fe Airless bodies

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Disaster effects of climate change in High Mountain Asia:State of art and scientific challenges Disaster effects of climate change in High Mountain Asia:State of art and scientific challenges

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Advances in Climate Change Research 2024年第3期15卷 367-389页

作者： Hao WANG Bin-Bin WANG Peng CUI Yao-Ming MA Yan WANG Jian-Sheng HAO yu WANG Ya-Mei LI Li-Jun SUN Jiao WANG Guo-Tao ZHANG Wei-Mo LI yu LEI Wen-Qing zhao Jin-Bo TANG Chao-yue LI Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China State Key Laboratory of Tibetan Plateau earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Institute of Geographic sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China china‒Pakistan Joint Research Center on earth sciences Chinese Academy of SciencesIslamabad 45320Pakistan college of earth and Planetary sciences University of Chinese Academy of SciencesBeijing 100049China college of Atmospheric science Lanzhou UniversityLanzhou 730000China National Observation and Research Station for Qomolongma Special Atmospheric Processes and Environmental Changes Dingri 858200China

High Mountain Asia(HMA)shows a remarkable warming tendency and divergent trend of regional precipitation with enhanced meteorological *** rapid thawing of the HMA cryosphere may alter the magnitude and frequency of nature *** reviewed the influence of climate change on various types of nature hazards in HMA region,including their phenomena,mechanisms and *** reveals that:1)the occurrences of extreme rainfall,heavy snowfall,and drifting snow hazards are escalating;accelerated ice and snow melting have advanced the onset and increased the magnitude of snowmelt floods;2)due to elevating trigger factors,such as glacier debuttressing and the rapid shift of thermal and hydrological regime of bedrock/snow/ice interface or subsurface,the mass flow hazards including bedrock landslide,snow avalanche,ice-rock avalanches or glacier detachment,and debris flow will become more severe;3)increased active-layer detachment and retrogressive thaw slumps slope failures,thaw settlement and thermokarst lake will damage many important engineering structures and infrastructure in permafrost region;4)multi-hazards cascading hazard in HMA,such as the glacial lake outburst flood(GLOF)and avalanche-induced mass flow may greatly enlarge the destructive power of the primary hazard by amplifying its volume,mobility,and impact force;and 5)enhanced slope instability and sediment supply in the highland areas could impose remote catastrophic impacts upon lowland regions,and threat hydropower security and future water *** future,ongoing thawing of HMA will profoundly weaken the multiple-phase material of bedrock,ice,water,and soil,and enhance activities of nature *** and cascading hazards of high magnitude will prevail in *** the glacier runoff overpasses the peak water,low flow or droughts in lowland areas downstream of glacierized mountain regions will became more frequent and *** escalating hazards in the HMA region requires tackling s

关键词： High Mountain Asia Climate change Cryosphere degradation Nature hazards Disaster risk

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Behavior and mechanism of graphene oxide-tris(4-aminophenyl)amine composites in adsorption of rare earth elements

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Journal of Rare earths 2021年第1期39卷 90-97,I0004页

作者： Xiaoru zhao Xinyu Jiang dongming Peng Jie Teng Jingang yu college of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China School of Pharmacy Hunan University of Chinese MedicineChangsha 410208China college of Materials science and Engineering Hunan UniversityChangsha 410082China

Three-dimensional(3D)graphene oxide-tris(4-aminophenyl)amine(GO-TAPAx:y)composites with different GO-to-TAPA mass ratios(x:y)were prepared by a facile one-step ultrasonic ***:y composites were characterized by scanning electron microscopy(SEM),nitrogen(N2)adsorption-desorption isotherms,Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and thermogravimetric analysis(TGA).Behavior and mechanism of GO-TAPAx:yco mposites for the adsorption of rare earth elements(REEs)were *** adso rption capacities of GO-TAPA1;2 composite for Yb^3+,Er^3+,Nd^3+,La^3+and Y^3+are 30.88,26.52,20.60,11.24 and 10.52 mg/g,*** of some important parameters including GO-to-TAPA mass ratios,contact time,reaction temperature and initial Yb^3+concentration on the adsorption were evaluated in *** spectral and XPS analyses show that the metal complexations and ion exchanges between nitrogen/oxygen-containing species of the adsorbents and REEs are involved in the adsorption procedure besides the conventional adsorption based on specific surface area,indicating the introduction of specific molecules onto GO is beneficial to its adsorption *** convenient reusability and applicability of GO-TAPAx:y composites toward real samples also demonstrate their feasibility in the enrichment of REE ions.

关键词： Graphene oxide Tris(4-aminophenyl)amine Enrichment Adsorption mechanism Rare earth elements

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火山区CO2气体释放研究进展

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矿物岩石地球化学通报 2018年第4期37卷 601-620页

作者：赵文斌郭正府孙玉涛张茂亮张丽红雷鸣马琳中国科学院地质与地球物理研究所新生代地质与环境重点实验室北京100029 中国科学院地球科学研究院北京100029 中国科学院大学北京100049 河北地质大学资源学院石家庄050031

不同构造域的火山释放CO2气体的方式、机制和规模具有明显的差异。在全球变暖的大背景下,定量化研究不同类型火山区CO2气体的释放通量、模拟及计算火山气体的来源演化,对于估算地质源温室气体释放对大气圈温室气体增加的贡献,以及理解... 详细信息

不同构造域的火山释放CO2气体的方式、机制和规模具有明显的差异。在全球变暖的大背景下,定量化研究不同类型火山区CO2气体的释放通量、模拟及计算火山气体的来源演化,对于估算地质源温室气体释放对大气圈温室气体增加的贡献,以及理解地球的深部碳循环过程具有重要意义。近年来,全球火山区CO2气体释放研究取得了显著进展,尤其在定量研究火山区CO2气体释放通量的方法、气体源区与地球动力学背景的判定以及不同构造背景的火山区CO2气体释放特征等领域取得了重大成果。本文综述了不同构造域火山区CO2气体释放研究的最新成果,详细介绍了我国新生代典型火山地热区的CO2气体释放研究进展。

关键词：火山区 CO2气体释放构造域深部碳循环火山监测

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样本量及其空间分布对物种分布模型的影响

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兰州大学学报（自然科学版） 2018年第2期54卷 208-215页

作者：赵晓冏巩娟霄赵莎莎孟浩贤闫伯前齐欣宇中国科学院西北生态环境资源研究院兰州730000 甘肃省环境科学设计研究院兰州730000 中国科学院大学北京100049 北京农学院食品科学系北京1022065 兰州大学资源环境学院兰州730000

在大量野外调查的基础上,结合SPOT遥感影像解译的太白红杉分布范围,采用从解译的太白红杉分布数据中提取的6种不同样本量、在不同海拔梯度和坡向的样本量分布以及3种不同的评价方法,测试了两种模型(MaxEnt,Garp)下太白红杉预测精度的变... 详细信息

在大量野外调查的基础上,结合SPOT遥感影像解译的太白红杉分布范围,采用从解译的太白红杉分布数据中提取的6种不同样本量、在不同海拔梯度和坡向的样本量分布以及3种不同的评价方法,测试了两种模型(MaxEnt,Garp)下太白红杉预测精度的变化.结果表明:随着样本量的增加,模型精度随之增大,预测结果趋于稳定.大样本量时,Garp模型的性能优于MaxEnt模型;小样本量时,MaxEnt模型预测结果最优.样本在不同海拔梯度和坡向分布时,两种模型样本量不均等分布的预测性能明显优于均等分布;相同样本分布下,两者预测能力没有明显差异.在保证一定样本量的前提下,为提高模拟能力,选择样本时应尽可能按照物种分布地的数量依比例取样.结果对合理采样和提高物种分布模拟精确度有重要意义,可用于指导物种分布模型的选择及其最优样本的获取.

关键词： MaxEnt模型 Garp模型 SPOT影像太白红杉

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A Localization Method of High Energy Transients for All-sky Gamma-ray Monitor

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Research in Astronomy and Astrophysics 2024年第10期24卷 25-35页

作者： Yi zhao Wangchen Xue Shaolin Xiong Qi Luo yuanhao Wang Jiacong Liu Heng yu Xiaoyun zhao yue Huang Jinyuan Liao Jianchao Sun Xiaobo Li Qibin Yi Ce Cai Shuo Xiao Shenglun Xie Chao Zheng Yanqiu Zhang Chenwei Wang Wenjun Tan Zhiwei Guo Chaoyang Li Zhenghua An Gang Chen Yanqi Du Min Gao Ke Gong Dongya Guo Jiang He Jianjian He Bing Li Gang Li Xinqiao Li Jing Liang Xiaohua Liang Yaqing Liu Xiang Ma Rui Qiao Liming Song Xinying Song Xilei Sun Jin Wang Ping Wang Xiangyang Wen Hong Wu Yanbing Xu Sheng Yang Dali Zhang Fan Zhang Hongmei Zhang Peng Zhang Shu Zhang Zhen Zhang Shijie Zheng Keke Zhang Xingbo Han Haiyan Wu Hu Tai Hao Geng Gaopeng Lu Wei Xu Fanchao Lyu Hongbo Zhang Fangjun Lu Shuangnan Zhang Department of Astronomy Beijing Normal UniversityBeijing 100875China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China university of chinese academy of sciences Beijing 100049China School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China college of Physics Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China School of Physics and Electronic science Guizhou Normal UniversityGuiyang 550001China Institute of Astrophysics Central China Normal UniversityWuhan 430079China college of physics sciences Technology Hebei UniversityBaoding 071002China Physics and Space science college China West Normal UniversityNanchong 637002China School of Computing and Artificial Intelligence Southwest Jiaotong UniversityChengdu 611756China college of Electronic and information Engineering Tongji UniversityShanghai 201804China Innovation academy for Microsatellites of chinese academy of sciences Shanghai 201304China National Space science Center Chinese Academy of SciencesBeijing 100190China School of earth and Space sciences University of Science and Technology of ChinaHefei 230026China Electronic Information School Wuhan UniversityWuhan 430072China Key Laboratory of Transportation Meteorology of china Meteorological Administration Nanjing Joint Institute for Atmospheric SciencesNanjing 210000China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Fast and reliable localization of high-energy transients is crucial for characterizing the burst properties and guiding the follow-up *** based on the relative counts of different detectors has been widely used for all-sky gamma-ray *** are two major methods for this count distribution localization:χ^(2)minimization method and the Bayesian *** we propose a modified Bayesian method that could take advantage of both the accuracy of the Bayesian method and the simplicity of the χ^(2)*** comprehensive simulations,we find that our Bayesian method with Poisson likelihood is generally more applicable for various bursts than the χ^(2)method,especially for weak *** further proposed a location-spectrum iteration approach based on the Bayesian inference,which could alleviate the problems caused by the spectral difference between the burst and location *** method is very suitable for scenarios with limited computation resources or timesensitive applications,such as in-flight localization software,and low-latency localization for rapidly follow-up observations.

关键词： methods:data analysis methods:analytical (stars:)gamma-ray burst:general

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Multifunctional Langmuir-Blodgett film of an Amphiphilic Benziminazole Styryl Dye

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Chemical Research in chinese Universities 2002年第3期18卷 325-329页

作者： ZHENG Jie LI Fu you HUANG Chun hui yu An Chi zhao Xin Sheng State Key Laboratory of Rare earth Materials Chemistry and Applications and the university of Hong Kong Joint Laboratory on Rare earth Materials and Bioinorgani Chemistry Peking UniversityBeijing 100871P.R.China college of Chemistry and Molecular Engineering Peking UniversityBeijing 100871P.R.China

An amphiphilic benziminazole styryl dye, 2 (4 dihexadecylaminostyryl)benziminazolium TCNQ -(DBTCNQ), was synthesized and successfully transferred onto the substrates by Langmuir Blodgett(LB) technique. H aggregates were formed on the substrates. Its monolayer second order susceptibility[ χ (2) zzz = 109 p/mV) was determined with a polarized laser beam(Nd∶YAG, λ =1.064 μm). The photoelectrochemistry of the dye LB monolayer films was investigated in a traditional three electrode cell. The quantum efficiency of photoelectric conversion is 1.08% under favorable conditions [-200 mV, 0.5 mg/mL methylviologen diiodide(MV 2+ ) in 0.5 mol/L KCl electrolyte solution]. The experimental data indicate that the LB film exhibits multifunctional properties.

关键词： Multifunction Langmuir Blodgett films Benziminazole styryl dye

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Alkali/alkaline-earth metal-modified MnO_(x) supported on three-dimensionally ordered macroporous–mesoporous Ti_(x)Si+(1-x)O_(2) catalysts:Preparation and catalytic performance for soot combustion

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Journal of Environmental sciences 2023年第3期125卷 82-94页

作者： Chao Peng Di yu Chunlei Zhang Maozhong Chen LanyiWang Xuehua yu Xiaoqiang Fan Zhen zhao Kai Cheng Yongsheng Chen yuechangWei Jian Liu Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Energy and Catalysis Laboratory Department of Mechanical and Automation EngineeringThe Chinese University of Hong KongHong KongChina

The performance of catalysts used in after-treatment systems is the key factor for the removal of diesel soot,which is an important component of atmosphericfine particle ***,three-dimensionally ordered macroporous–mesoporous Ti_(x)Si+(1-x)O_(2)(3DOM-m Ti_(x)Si+(1-x)O_(2)) and its supported MnO_(x)catalysts doped with different alkali/alkaline-earth metals (AMnO_(x)/3 DOM-m Ti_(0.7)Si_(0.3)O_(2)(A:Li,Na,K,Ru,Cs,Mg,Ca,Sr,Ba)) were prepared by mesoporous template (P123)-assisted colloidal crystal template (CCT) and incipient wetness impregnation methods,*** characterizations of the catalysts were performed using scanning electron microscopy,X-ray diffraction,N_(2)adsorption–desorption,H_(2)temperature-programmed reduction,O_(2)temperature-programmed desorption,NO temperature-programmed oxidation,and Raman spectroscopy techniques;then,we evaluated their catalytic performances for the removal of diesel soot *** results show that the 3DOM-m Ti_(0.7)Si_(0.3)O_(2)supports exhibited a well-defined 3DOM-m nanostructure,and AMnO_(x)nanoparticles with 10–50 nm were evenly dispersed on the inner walls of the uniform *** addition,the as-prepared catalysts exhibited good catalytic performance for soot *** the prepared catalysts,CsMnO_(x)/3DOM-m Ti_(0.7)Si_(0.3)O_(2)had the highest catalytic activity for soot combustion,with T10,T50,and T90(the temperatures corresponding to soot conversion rates of 10%,50%,and 90%) values of 285,355,and 393℃,*** high catalytic activity of the CsMnO_(x)/3 DOM-m Ti_(0.7)Si_(0.3)O_(2)catalysts was attributed to their excellent low-temperature reducibility and homogeneous macroporous–mesoporous structure,as well as to the synergistic effects between Cs and Mn species and between CsMnO_(x)and the Ti_(0.7)Si_(0.3)O_(2)support.

关键词： Three-dimensionally ordered macroporous-mesoporous Ti_(0.7)Si_(0.3)O_(2) Alkali/alkaline-earth metals MnO_(x) Catalysts Preparation Soot combustion

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