Lithium mapping in a Mg-9Li-4Al-1Zn alloy using electron energy-loss spectroscopy

Magnesium-lithium alloys with high lithium content have been attracting significant attention because of their low density,high formability and corrosion resistance.These properties are dependent on the distribution of lithium,which is difficult to map in the presence of magnesium.In this work,a ratio spectrum-imaging method with electron energy-loss spectroscopy(EELS)is demonstrated,which enables the mapping of lithium.In application to LAZ941(Mg-9Li-4Al-1Zn in wt.%),this technique revealed that a key precipitate in the microstructure,previously thought by some to be Mg_(17)Al_(12),is in fact rich in lithium.This result was corroborated with a structural investigation by high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM),showing this phase to be Al_(1-x)Zn_(x)Li,with x<<1.This work indicates the potential offered by this technique for mapping lithium in materials.

Assessment of International GNSS Service Global Ionosphere Map products over China region based on measurements from the Crustal Movement Observation Network of China

The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of GIM products in data-sparse regions is of paramount importance.In this study,measurements from the Crustal Movement Observation Network of China(CMONOC)are leveraged to evaluate the suitability of IGS-GIM products over China region in 2013-2014.The indices of mean error(ME),root mean square error(RMSE),and normalized RMSE(NRMSE)are then utilized to quantify the accuracy of IGS-GIM products.Results revealed distinct local time and latitudinal dependencies in IGS-GIM errors,with substantially high errors at nighttime(NRMSE:39%)and above 40°latitude(NRMSE:49%).Seasonal differences also emerged,with larger equinoctial deviations(NRMSE:33.5%)compared with summer(20%).A preliminary analysis implied that the irregular assimilation of sparse IGS observations,compounded by China’s distinct geomagnetic topology,may manifest as error variations.These results suggest that modeling based solely on IGS-GIM observations engenders inadequate representations across China and that a thorough examination would proffer the necessary foundation for advancing regional total electron content(TEC)constructions.

Data Logic Structure and Key Technologies on Intelligent High-precision Map

Taking autonomous driving and driverless as the research object,we discuss and define intelligent high-precision map.Intelligent high-precision map is considered as a key link of future travel,a carrier of real-time perception of traffic resources in the entire space-time range,and the criterion for the operation and control of the whole process of the vehicle.As a new form of map,it has distinctive features in terms of cartography theory and application requirements compared with traditional navigation electronic maps.Thus,it is necessary to analyze and discuss its key features and problems to promote the development of research and application of intelligent high-precision map.Accordingly,we propose an information transmission model based on the cartography theory and combine the wheeled robot’s control flow in practical application.Next,we put forward the data logic structure of intelligent high-precision map,and analyze its application in autonomous driving.Then,we summarize the computing mode of“Crowdsourcing+Edge-Cloud Collaborative Computing”,and carry out key technical analysis on how to improve the quality of crowdsourced data.We also analyze the effective application scenarios of intelligent high-precision map in the future.Finally,we present some thoughts and suggestions for the future development of this field.

The Organization of Multimedia Information in Electronic Map

On the basis of an electronic map_based hypermedia data model (EMBHDM),this paper makes a study on the technologies of nonlinear storage,organization,management and browsing of information as well as organization of data on the basis of the relationship between multimedia information of electronic maps. This paper first analyzes some features of electronic maps and hypermedia technology,and then illustrates the creation of EMBHDM with some examples.The tests show that this model can efficiently organize and express multimedia data.

Visualization issues in the development of electronic atlas in China

In this paper, we discuss the development of electronic atlas in China, with focus on the issues of visualization. We particularly categorise this development into four periods, and then analyse the characters in each period and discuss the visualization issues. The four periods are highlighted: 1) Infant period (<1990) characterized as computer assisted mapping with products of screen maps; 2) Starting period (1991-1995) characterized as object-oriented mapping with products of interactive maps/atlases; 3) Advancing period (1996-2000) characterized as integrated mapping with products of multimedia cartographic maps; 4) New era (> 2001) characterized as web mapping and adaptive map design with products of Internet maps and atlas as well as adaptive maps. It is obvious that the development follows the logical way from static to dynamic, and even real time visualization, from single user to multiple users, from presentation to exploration for effective communication and knowledge construction. Current research and development projects are focused on customisation of atlas information systems for real-time tasks, Internet operability, small displays and mobile environments. The major challenges involved in each of such customisation processes are identified and commented in relation to the further development of visualization.

DESIGN AND COMPILATION OF AGRICULTURAL ELECTRONIC ATLAS AT COUNTY-LEVEL

:With the rapid development and application of new techniques,cartograp hy has entered the 21st centu-ry’s digital period from computer-a ssist mapping in the 1970s,traditio nal map representation has transformed from 2-D,mono-medium,static into 3-D,multi-media,dynamic and network(including internet),and gradually is developing to-wards 4-D(time,space).There appeared digital map,electr onic map,soft map,hard map,interac tive map,mingle map etc.Agricultural map needs to in clude much more contents in 3-D,multi-media than other types of map.Only electron-ic mapcanrepresentcompletely these contents.Compiling agricultural electronic atlas atcounty-levelaims to reflectscientifi-cally China’s modernization agricu lture development level,the new ach ievements of agricultural science a nd technology.Agricultural electronic atlas at county-level should take“sustainable development as the theme;systematically reflec t the natural resources and natural en vironment in a county;the spatial an d temporal distribution and changin g lawof agricultur-al resources(including climate,soil and water).In the paper the authors introduce t he concrete contents of agricultura l electronic atlas,their compilatio n process,and corresponding software and hard ware as well as an example.In agricul tur-al electronic atlas design the most advanced multi-media techniques must be used.The procedure of agricultu ral electron-ic atlas includes the study on compilation aim,content selection analysis,overall framework and data organ ization,determin-ing compilation program.Agricultu re includes many contents;each county has its own emphasis.In designing we set up a county’s theme according to its con crete situation,the atlas contents are selected around the theme.For example,the main problems faced by the agricultu re of Da’an City in Jilin Province is l and desertification,so land desertification and its control are the theme of agricult ural electronic atlas of Da’an City.When we compile other county’s agric ultural electron-ic atlas,only changing theme conten ts,can we get another county’s agric ultural electronic atlas.

Magnetic Properties and Electronic Structure of ThCo₄B

We present density functional theory DFT ab initio calculation of the electronic and magnetic properties of ThCo4B compound using the self-consistent full-potential linearized augmented plane wave (FPLAPW) method as implemented in the Wien2k package. The influence of the local environment on the Co magnetic moments is discussed by comparing the magnetic and electronic properties of ThCo4B to its parent ThCo5 compound. The total magnetic moment in these two compounds is dominated by the Co moment. The Spin orbit interaction affects the electronic structure and spin-density maps of the p-state of Th.

Uncovering the internal structure of five-fold twinned nanowires through 3D electron diffraction mapping

Five-fold twinned nanostructures are intrinsically strained or relaxed by extended defects to satisfy the space-filling requirement.Although both of metallic and semiconductor five-fold twinned nanostructures show inhomogeneity in their cross-sectional strain distribution,the evident strain concentration at twin boundaries in the semiconductor systems has been found in contrast to the metallic systems.Naturally,a problem is raised how the chemical bonding characteristics of various five-fold twinned nanosystems affects their strain-relieving defect structures.Here using three-dimensional(3D)electron diffraction mapping methodology,the intrinsic strain and the strain-relieving defects in a pentagonal Ag nanowire and a star-shaped boron carbide nanowire,both of them have basically equal radial twin-plane width about 30 nm,are nondestructively characterized.The non-uniform strain and defect distribution between the five single crystalline segments are found in both of the five-fold twinned nanowires.Diffraction intensity fine structure analysis for the boron carbide five-fold twinned nanowire indicates the presence of high-density of planar defects which are responsible for the accommodation of the intrinsic angular excess.However,for the Ag five-fold twinned nanowire,the star-disclination strain field is still present,although is partially relieved by the formation of localized stacking fault layers accompanied by partial dislocations.Energetic analysis suggests that the variety in the strain-relaxation ways for the two types of five-fold twinned nanowires could be ascribed to the large difference in shear modulus between the soft noble metal Ag and the superhard covalent compound boron carbide.

Electron Energy Spectroscopic Mapping of Surface Plasmon by Parallel Scanning Method

In this work,electron energy spectroscopic mapping of surface plasmon of Ag nanostructures on highly oriented pyrolytic graphite is reported.Benefitting from the angular dispersive feature of the present scanning probe electron energy spectrometer,a multi-channel detection mode is developed.By scanning along one direction,the two-dimensional intensity distribution of Ag surface plasmon excitation due to the collision of electron emitted from the tip can be obtained in parallel.The spectroscopic spatial resolution is determined to be around 80 nm.

Environmental Effects on Electronic Devices in Mexico

This paper shows the results of the assessment of impairment suffered by elements of electronic equipment by environmental effects in different climatic zones of Mexico. For this study, evaluated devices were evaluated that are mostly exposed under different climatic conditions of operation, to determine the degree of damage suffered which leads to malfunction, reduced service life and loss of information in some cases. The main contribution is to identify the causes of the deterioration to delay the effect of atmospheric corrosion deterioration in electronic components. The Mexican Republic has a wide range of climates and subclimates over its territory, sampling was performed for each one of the most representative regions, by their nature tend to be more conducive to the release of corrosive effect on the computer and electronic devices. For the determination of existing impairment in electronic equipment, a methodology is proposed for the evaluation of samples taken from each region, determining the degree of corrosion that exists in these devices. It should be noted that according to the literature, the main pollutants that lead to the deterioration caused by corrosive environmental phenomena are SO2, NOx, CO, CO2, coupled with the presence of ozone and chloride, characteristic of the coastal region, combined with the percent relative humidity (% HR), and temperature cycles as reported by environmental monitoring systems in Mexico. With the study of atmospheric corrosivity in electronic devices has been determined: 1) Design and operation of chamber to accelerated atmospheric corrosion testing. 2) Identification of electronic components with increased susceptibility to corrosive phenomena under typical environmental different regions of Mexico. 3) Correlation of damage suffered in electronic equipment under typical operating conditions and accelerated tests. 4) Determining the degree of atmospheric corrosion on electronic equipment. 5) Construction of atmospheric corrosivity map for Mexico in electronic devices.

基于VR技术的野外实践平台构建

传统野外实践受地域、交通、时间、天气等多重因素的制约,难以兼顾实践内容、成本及人员的安全。采集不同时间、不同地点的影像素材制作VR实景,叠加至电子地图并通过互联网发布,可实现实践对象空天地一体化的多尺度展示。基于VR技术构建与应用野外实践平台,拓展了野外实践的地域范围,同时降低教学成本和风险。VR实景的制作及发布所涉及的技术门槛低,节点的拓展性强,有利于提高野外实践教学资源共享效益,为全国性的仿真平台建设提供参考。

铁路三维电子沙盘搭建及其应用研究

为解决目前铁路行业电子沙盘存在的表达方式不一、应用内容单一、数据泄露风险大、数据加载效率低等问题,研究海量地理地质及BIM模型的数据处理、管理和应用方法,建立以BIM+GIS为技术核心的标准化电子沙盘,从而更好地服务于铁路设计和建造。根据鲁南高铁、拉林铁路、成渝中线高铁等项目实践总结,在中国铁路BIM联盟和国铁集团相关标准基础上提出了面向电子沙盘应用的地形、影像、BIM模型、专题图的数据制作标准,从坐标转换、数据转换、数据切片、知识图谱建立、模型发布、前端数据汇集的方法完成了电子沙盘的搭建。最后,在电子沙盘中实现了百公里级、多专业数据的在线高效组织和管理,提出的方法和标准适用于铁路设计、建设过程的管理和分析应用。

基于电子鼻和气质联用分析萌芽大蒜挥发性物质差异

为探究萌芽期大蒜挥发性物质的差异,采用电子鼻、捕集阱顶空-气质联用仪(Trap head space-gas chromatography-mass spectrometry,HS-Trap-GC-MS)结合正交偏最小二乘法判别分析(Orthogonal partial least squares discriminant analysis,OPLS-DA)、香气活度值、差异性热图、相关性分析分析大蒜萌芽在0、24、48、72、96 h挥发性物质的差异。电子鼻结合OPLS-DA建立预测模型其预测能力达96.00%。GC-MS分析表明:含硫化合物是不同萌芽期大蒜的主要共有挥发性物质,含硫化合物的相对含量随萌芽时间的延长而呈递减趋势,而种类呈现出递增趋势;二烯丙基二硫醚是样品在萌芽过程中含量降低最多的物质。二烯丙基四硫醚、烯丙硫醇是样品共有关键化合物。差异性热图分析显示:除共有物质含量差异外,硫化丙烯、己醛、叠氮二羧酸二叔丁酯、丙烯醇、6-甲基-2-庚炔、5-甲基噻二唑、2-亚乙基-1,3-二硫烷、2-丙-2-炔基磺酰基丙烷、2,5-二甲基噻吩、2,5-二甲基呋喃、1-戊烯-3-醇、1,3-二噻烷的缺失进一步加大了未萌芽和萌芽大蒜气味的差异。萌芽大蒜主要共有挥发性物质的种类随萌芽时间的延长呈现递增趋势。大蒜主要挥发性物质与电子鼻大多数传感器存在显著相关性。大蒜的气味强度会随萌芽时间的延长而逐步减弱。

基于混沌序列的电子档案上传加密方法

为了提升数据的存储效率和电子档案的传输安全性,设计了一种基于混沌序列的电子档案上传加密方法(混沌序列方法).以形式化方案分解电子档案上传步骤,在交互过程中统一定义上传形式.采用Logistic映射关系表示混沌模式;给定混沌序列变化区间,随机生成档案加密密钥流;在保证电子档案可完整解密的前提下,设定密文置换规则,设置置换流程,根据可逆关系调整密文顺序,完成电子档案的加密上传.在光纤网络配置基础上模拟电子档案上传全过程,实验结果表明,混沌序列方法能够在10 s内生成128 bit加密密钥,且在规定时间内完成498组1.5 GB内存大小的电子档案传输.

导航电子地图著作权保护的边界分析与路径选择

导航电子地图作为一种新型数字资源,具有重要的实用价值和商业价值。伴随数字经济时代下技术的飞速发展和数据信息的广泛共享,导航电子地图的知识产权保护面临诸多新挑战,相伴而生的著作权保护问题频发。加强导航电子地图的著作权保护需要厘清导航电子地图著作权保护的基础法律关系,依据“思想与表达二分法”排除导航电子地图中不受保护的“思想”。导航电子地图中构成作品的地图数据应当受到著作权法保护,对于不构成作品的地图数据,著作权法可以保护基于地图数据利用的行为。涉及导航电子地图著作权侵权责任问题时,有必要提高侵权赔偿的计算标准,吸纳惩罚性赔偿的规定。导航电子地图的著作权保护还需要强化协同治理措施,充分发挥导航电子地图行业协会的监管职能,强化导航电子地图审核部门的登记保护效力,促进导航电子地图著作权保护的理论创新和可持续发展。

水利信息管理平台设计与实现

随着信息化的发展,在面对海量信息管理方面,传统管理方式和手段已无法胜任。本文以启东市为例,采用HTML5+GIS构建了水利信息管理平台,通过平台对多源数据进行综合管理、分析,快速、全面地掌握水利设施的分布情况、运行状态,使水利管理人员能够更加方便地对各种水利设施空间信息进行可视化管理,并结合水利管理业务和技术应用需要,为水利管理决策分析提供科学依据。

基于MAPINFO电子地图制作方法研究

研究利用 Map Info商用 GIS软作制作电子地图的方法 ,分析在制作过程中的关键技术问题 。

元素周期表中的电子亲和势及砷电子亲和势的测量示例

基于先前对原子的电子亲和势和原子负离子的分析工作[J.Phys.Chem.Ref.Data 51,021502(2022)],本篇综述提供了一个关于原子的电子亲和势的简要概述.本文简要描述和对比了三种常用的测量电子亲和势的实验方法,以凸显它们各自的优缺点.为了阐明目前研究中所使用的慢电子速度成像法的特点,本文对砷元素(As)的电子亲和势以及其负离子(As-)的激发态进行了测量.测得As元素的电子亲和势为6488.61(5)cm^(-1)或0.804485(6)eV.实验清晰地分辨了As-的精细结构,其激发态^(3)P_(1)能量比基态^(3)P_(2)的能量高出1029.94(18)cm^(-1)或0.12770(3)eV;激发态^(3)P_(0)能量比基态^(3)P_(2)的能量高出1343.04(55)cm^(-1)或0.16652(7)eV.

基于MapGIS-IMS的WebGIS应用研究

通过与传统的GIS技术进行比较,介绍了WebGIS的概念、特点和体系结构模型,并介绍基于MapGIS IMS的旅游电子地图的开发流程、各项功能实现的原理和一些技术难点的解决方法。

基于MapInfo与MapX的电子地图

随着GIS(地理信息系统)的发展与完善,它的开发工具也日趋成熟。MapInfo公司顺应这发展潮流,开发了MapInfo以及MapX控件,可以实现复杂的GIS系统设计。根据桂林市规划地图,首先利用MapInfo 9.5构建地图数据,然后通过Geoset Manager生成Geoset格式文件,最后在Visual Studio 2008编程环境下、利用C#编程语言对MapX控件进行二次开发,最终实现桂林市电子地图。