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关于空间科学发展的一些思考

中国科学院院刊 2022年第8期37卷 1031-1049页

作者：顾逸东中国科学院空间应用工程与技术中心北京100094

空间科学是利用空间飞行器探索宇宙和自然规律,开展特殊实验的大规模科学活动,为当代科学发展作出了重大贡献。文章概述了国际空间科学的重大突破,分析了空间科学、载人探索活动的发展脉络和新趋势,回顾了我国空间科学近20年来的发展成... 详细信息

空间科学是利用空间飞行器探索宇宙和自然规律,开展特殊实验的大规模科学活动,为当代科学发展作出了重大贡献。文章概述了国际空间科学的重大突破,分析了空间科学、载人探索活动的发展脉络和新趋势,回顾了我国空间科学近20年来的发展成就,总结了存在的问题和差距,强调空间科学的战略地位及其对我国科技、航天和国家长远发展的重要性。加大对空间科学的投入、制定国家空间科学规划和建立稳定预算制度是我国空间科学长期稳定发展的保证。建议充分利用科学气球、探空火箭等各种途径夯实研究基础,加强理论与实验技术相结合,培养大批高素质科学家,深化国际合作,完善科学任务管理模式等,走出中国特色的空间科学创新发展道路。

关键词：空间科学发展规划国家预算研究基础工程管理

Controllable fabrication of FeCoS_(4) nanoparticles/S-doped bowl-shaped hollow carbon as efficient lithium storage anode

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Chinese Journal of Chemical Engineering 2024年第3期67卷 78-88页

作者： Ming Zhou Mengrong Wu Haiwei Yu Xiangjun Zheng Kuan Shen Xingmei guo Yuanjun Liu Fu Cao Hongxing gu Qinghong Kong Junhao Zhang School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Jiangsu Hengshen Co. LtdZhenjiang 212314China School of the Environment and Safety Engineering Jiangsu UniversityZhenjiang 212013China

To address the low conductivity and easy agglomeration of transition metal sulfide nanoparticles,FeCoS_(4) nanoparticles embedded in S-doped hollow carbon(FeCoS_(4)@S-HC)composites were successfully fabricated through a combination of hydrothermal processes and sulfidation *** unique bowlshaped FeCoS_(4)/S-HC composites exhibit excellent structural stability with a high specific surface area of 303.7 m^(2)·g^(-1) and a pore volume of 0.93 cm^(3)·g^(-1).When applied as anode material for lithium-ion batteries,the FeCoS_(4)@S-HC anode exhibits efficient lithium storage with high reversible specific capacity(970.2 mA·h·g^(-1) at 100 mA·g^(-1))and enhanced cycling stability(574 mA·h·g^(-1) at 0.2 A·g^(-1) after 350 cycles,a capacity retention of 84%).The excellent lithium storage is attributed to the fact that the bimetallic FeCoS_(4) nanoparticles with abundant active sites can accelerate the electrochemical reaction kinetics,and the bowl-shaped S-HC structure can provide a stable mechanical structure to suppress volume expansion.

关键词： Bimetallic sulfides Bowl-shaped hollow carbon S doping Buffering volume expand Lithium-ion batteries

Major and Trace Elements of Magnetite from the Qimantag Metallogenic Belt: Insights into Evolution of Ore–forming Fluids

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Acta Geologica Sinica(English Edition) 2015年第4期89卷 1226-1243页

作者： YI Liwen gu Xiangping LU Anhuai LIU Jianping LEI Hao WANG Zhiling CUI Yu ZUO Hongyan SHEN Can Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitor Ministry of Education School of Geosciences and Info–Physics Central South University

Magnetite, as a genetic indicator of ores, has been studied in various deposits in the world. In this paper, we present textural and compositional data of magnetite from the Qimantag metallogenic belt of the Kunlun Orogenic Belt in China, to provide a better understanding of the formation mechanism and genesis of the metallogenic belt and to shed light on analytical protocols for the in situ chemical analysis of magnetite. Magnetite samples from various occurrences, including the ore-related granitoid pluton, mineralised endoskarn and vein-type iron ores hosted in marine carbonate intruded by the pluton, were examined using scanning electron microscopy and analysed for major and trace elements using electron microprobe and laser ablation-inductively coupled plasma-mass spectrometry. The field and microscope observation reveals that early-stage magnetite from the Hutouya and Kendekeke deposits occurs as massive or banded assemblages, whereas late- stage magnetite is disseminated or scattered in the ores. Early-stage magnetite contains high contents of Ti, V, Ga, AI and low in Mg and Mn. In contrast, late-stage magnetite is high in Mg, Mn and low in Ti, V, Ga, AI. Most magnetite grains from the Qimantag metallogenic belt deposits except the Kendekeke deposit plot in the ＂ Skarn ＂ field in the Ca＋AI＋Mn vs Ti＋V diagram, far from typical magmatic Fe deposits such as the Damiao and Panzhihua deposits. According to the （MgO＋MnO）- TiO^-AI203 diagram, magnetite grains from the Kaerqueka and Galingge deposits and the No.7 ore body of the Hutouya deposit show typical characteristics of skarn magnetite, whereas magnetite grains from the Kendekeke deposit and the No.2 ore body of the Hutouya deposit show continuous elemental variation from magmatic type to skarn type. This compositional contrast indicates that chemical composition of magnetite is largely controlled by the compositions of magmatic fluids and host rocks of the ores that have reacted with the fluids. Moreover, a co

关键词： Magnetite trace element LA-ICP-MS ore genesis Qimantag metallogenic belt

基于改进的广义S变换的低频吸收衰减梯度检测

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地球物理学报 2011年第9期54卷 2407-2411页

作者：张固澜中国石油集团东方地球物理公司新兴物探开发处河北涿州072751

本文利用一种改进的广义S变换对地震波进行时频分解,求取地震波低频段时频谱的吸收衰减梯度,并与利用传统的广义S变换得到的高频段及低频段的吸收衰减梯度进行对比,以期更好地指示油气.理论推导、数值模拟及实际应用结果表明:基于改进... 详细信息

本文利用一种改进的广义S变换对地震波进行时频分解,求取地震波低频段时频谱的吸收衰减梯度,并与利用传统的广义S变换得到的高频段及低频段的吸收衰减梯度进行对比,以期更好地指示油气.理论推导、数值模拟及实际应用结果表明:基于改进的广义S变换的低频吸收衰减梯度可与传统的广义S变换得到的高频吸收衰减梯度相互佐证,更好指示油气.

关键词：改进的广义S变换高频低频吸收衰减梯度

An Experimental Study on the Dissipation Effect of a Baffle Downstream of a Weir

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Engineering（科研） 2017年第11期9卷 937-949页

作者： Joon-gu Kang River Experiment Center Korea Institute of Civil Engineering and Building Technology Andong South Korea

This study is an experimental study to analyze the dissipation effect of a baffle shape installed to reduce the scour problem downstream of a weir. The hydraulic experiment on the flow dissipation effect created by baffle installation was an experiment under a fixed bed condition to investigate the flow dissipation effect based on changes in flow in the apron downstream caused by?changes in baffle shape. The experimental analysis was conducted by measuring the flow rate at the apron downstream with and without the installation of a baffle on the basis of the flow dissipation effect. This experiment compared the flow dissipation effect achieved with five baffle shapes to analyze the effect of the baffle shape. Two conditions of flow rate were considered: when a water level in the area of super-critical flow was lower than the baffle height, and when it?flowed over the baffle. Overall, the flow dissipation effect was found to be?good when a square baffle with a large flow blocking area was used. The analysis also found that hydraulic jump was facilitated when the front part of the baffle was inclined, as flow was induced to the upper direction. The result of the experiment showed that when performing flow dissipation through the use of a baffle, the effect of flow blocking and flow duration alteration should be considered.

关键词： Weir Scour Baffle Flow Dissipation

Nitrate leaching of winter wheat grown in lysimeters as affected by fertilizers and irrigation on the North China Plain

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Journal of Integrative Agriculture 2015年第2期14卷 374-388页

作者： gu Li-min LIU Tie-ning ZHAO Jun DONG Shu-ting LIU Peng ZHANG Ji-wang ZHAO Bin State Key Laboratory of Crop Biology College of Agronomy/National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources Shandong Agriculture University

Proper application of nitrogen（N） fertilizers and irrigation management are important production practices that can reduce nitrate leaching into groundwater and improve the N use efficiency（NUE）. A lysimeter/rain shelter facility was used to study effects of the rate of N fertilization, type of N fertilizer, and irrigation level on key aspects of winter wheat production over three growing seasons（response variables were nitrate transport, N leaching, and NUE）. Results indicated that nitrate concentration in the soil profile and N leaching increased with the rate of N fertilization. At the end of the third season, nitrate concentration in the top 0–75 cm layer of soil was higher with manure treatment while urea treatments resulted in higher concentrations in the 100–200 cm layer. With normal irrigation, 3.4 to 15.3% of N from applied fertilizer was leached from the soil, yet no leaching occurred under a stress irrigation treatment. The manure treatment experienced less N leaching than the urea treatment in all cases except for the 180 kg N ha^-1 rate in 2011–2012（season 3）. In terms of grain yield（GY）, dry matter（DM） or NUE parameters, values for the manure treatment were lower than for the urea treatment in 2009–2010（season 1）, yet were otherwise higher for urea treatment in season 3. GY and crop nitrogen uptake（NU） were elevated when the rate of N fertilizer increased, while the NUE decreased; GY, DM, and NU increased with the amount of irrigation. Data indicated that reduced rates of N fertilization combined with increased manure application and proper irrigation management can lower nitrate levels in the subsoil and reduce potential N leaching into groundwater.

关键词： fertilization irrigation nitrate vertical transport nitrogen leaching nitrogen use efficiency manure lysimeter

Dynamic observation of oxygen vacancies in hafnia layer by in situ transmission electron microscopy

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Nano Research 2015年第11期8卷 3571-3579页

作者： Chao Li Yuan Yao Xi Shen Yanguo Wang Junjie Li Changzhi gu Richeng Yu Qi Liu Ming Liu Beijing National Laboratory of Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China Laboratory of Nano-Fabfication and Novel Devices Integrated Technology Institute of Microelectronics Chinese Academy of Sciences Beijing 100029 China

The charge-trapping process, with HfO2 film as the charge-capturing layer, has been investigated by using in situ electron energy-loss spectroscopy and in situ energy-filter image under positive external bias. The results show that oxygen vacancies are non-uniformly distributed throughout the HfO2 trapping layer during the programming process. The distribution of the oxygen vacancies is not the same as that of the reported locations of the trapped electrons, implying that the trapping process is more complex. These bias-induced oxygen defects may affect the device performance characteristics such as the device lifetime. This phenomenon should be considered in the models of trapping processes.

关键词： charge-trapping flash in situ TEM electric field oxygen vacancy

As the Facade of History and Cultural Expressions

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China's Foreign Trade 2014年第Z1期 64-65页

作者： gu Zheng

Facade(Facade)is an architectural term,which mainly refers to the front of a *** meet the needs of living functions,architectural aesthetics,political and economic status of the owner,etc,the designer needs to turn the facade into a planar space qualified for various requirements such as ideology,aesthetic taste and function,*** this sense,Facade is not only required by a practical functional requirement but also by an aesthetic *** owner and designer

关键词： qualified owner designer aesthetic architectural p

Protection and development of agricultural heritage from the perspective of stakeholders

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Ecological Economy 2020年第1期16卷 8-16页

作者： gu Ya-qing Qianjiang College Hangzhou Normal UniversityHangzhou 310018CHINA

Based on the stakeholder theory,field interviews and surveys were carried out among 332 stakeholders of Shaoxing ancient Torreya grandis groups,including local government,tourists,tourism enterprises,local residents and heritage *** paper aims to analyze the main demands of various stakeholders,and the cognitive and interest demands,by means of SPSS23,in the process of agricultural cultural heritage protection and tourism *** is believed that the local resources endowment is favorable,but the tourism development and the protection of agricultural cultural heritage are in a state of separation,or even ***,the corresponding development countermeasures should be put forward from the common interest appeal of the five core interest groups.

关键词： stakeholders agricultural cultural heritage Shaoxing ancient Torreya grandis group