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A newly unraveled 13.6-year oscillation from GPS displacements and its potential implications for the dynamic reference frame

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Science China Earth Sciences 2024年第10期67卷 3204-3212页

作者： Hao DING Weiping jiang School of Geodesy and Geomatics Hubei Luojia LaboratoryWuhan UniversityWuhan 430079China GNSS Research Center Wuhan UniversityWuhan 430079China

Numerous practical geodetic and geophysical applications necessitate precise measurements of GNSS displacements at the millimeter or sub-millimeter level. To attain such precision, it is imperative to identify and analyze the unidentified decadal signals inherent in the GPS displacements. In this research, we employ the optimal sequence estimation method to effectively detect an about 13.6-year oscillational signal with an excited amplitude of 3.6±1.2 mm in the U-components of the GPS displacements. It is noteworthy that this signal demonstrates a consistent spatial pattern characterized by the spherical harmonic Y_(2,-2). We conduct a comparative analysis with the 13.6-year oscillation observed in length-of-day variations(and geomagnetic records), finding that they are in reverse phase. After eliminating the Earth's external excitation sources through the utilization of two distinct in-situ hydrological records, we suggest that the 13.6-year GPS signal may come from the internal motions within the Earth. However, the specific excitation source and the detailed physical mechanism remain uncertain. Additionally, we develop a mathematical displacement model to explain the 13.6-year signal. Our findings indicate that this signal can result in displacements of up to 1.37 mm and velocity effects of 0.63 mm/yr(for U-component) at maximum. These results underscore the necessity of incorporating this 13.6-year signal into the construction and maintenance of a dynamic reference frame at the millimeter level.

关键词： GPS displacements Decadal changes 13.6-year oscillation Displacement model Dynamic reference frame

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干扰信道中一种改进的干扰消除方法

计算机工程 2015年第7期41卷 120-123页

作者：田心记姜利敏河南理工大学计算机科学与技术学院河南焦作454000 安阳师范学院人文管理学院河南安阳455002

针对三用户的多输入多输出干扰信道,提出一种新的基于空时编码的干扰消除方法。每个用户采用速率为2的空时分组码对每个码字进行2层预编码,一层预编码对齐第2个接收端收到的2个干扰信号,且与第3个接收端收到的干扰信号对齐,另一层预编... 详细信息

针对三用户的多输入多输出干扰信道,提出一种新的基于空时编码的干扰消除方法。每个用户采用速率为2的空时分组码对每个码字进行2层预编码,一层预编码对齐第2个接收端收到的2个干扰信号,且与第3个接收端收到的干扰信号对齐,另一层预编码消除这2个接收端的多用户干扰,并结合单向协作链路消除第一个接收端的多用户干扰。仿真结果表明,与相同场景中采用Alamouti编码的干扰消除方法相比,该方法能提高传输效率,且可靠性较高。

关键词：多输入多输出干扰信道空时分组码干扰对齐多用户干扰预编码

Capturing Plateau-Rayleigh instability in silver nanowires via ultrafast electron microscopy

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Nano Research 2024年第9期17卷 8402-8407页

作者： Shuai jiang Volkan Ortalan Department of Materials Science and Engineering University of ConnecticutStorrsCT 06269USA

Understanding the structural stability of nanomaterials such as nanowires is imperative for their practical ***,using single-shot ultrafast transmission electron microscopy,we captured the Plateau-Rayleigh instability behavior of silver nanowires decomposing into silver nanoparticles upon laser irradiation on nanosecond time *** found that this dynamic process can be accelerated by a factor of 10 through increasing the peak laser fluence from 6.03 to 14.60 mJ/cm^(2).Moreover,by comparing the laser fluence required to initiate the Plateau-Rayleigh instability in silver nanowires on carbon and Formvar membranes,it was found that the main driving force for the Plateau-Rayleigh instability in this study was substrate *** element analysis and molecular dynamics simulations are also applied to estimate the temperature jump of the nanowires and atomistic behavior,*** addition,the complex motions of silver nanowires under laser irradiation were systematically investigated by combining the results of ultrafast transmission electron microscopy with scanning electron microscopy characterizations and were determined to be related to nanowire-membrane interactions or pre-existing stresses on the nanowires,which in turn demonstrated the potential of ultrafast transmission electron microscopy for the characterization of nanomaterials and devices under extreme conditions.

关键词： silver nanowire Plateau-Rayleigh instability ultrafast transmission electron microscopy molecular dynamics simulation

Mo_(2)B_(2)O_(2)MBene for Efficient Electrochemical CO Reduction to C_(2)Chemicals:Computational Exploration

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Energy & Environmental Materials 2024年第6期7卷 342-350页

作者： Bikun Zhang Jianwen jiang Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117576Singapore

Emerging as a new class of two-dimensional materials with atomically thin layers,MBenes have great potential for many important applications such as energy storage and *** mitigating carbon footprint,there has been increasing interest in CO_(2)/CO conversion on MBenes,but mostly focused on C_(1)products.C^(2+)chemicals generally possess higher energy densities and wider applications than C_(1)***,C–C coupling is technically challenging because of high energy requirement and currently few catalysts are suited for this ***,we explore electrochemical CO reduction reaction to C_(2)chemicals on Mo_(2)B_(2)O_(2)MBene via density-functional theory ***,the most favorable CO–COH coupling is revealed to be a spontaneous and barrierless process,making Mo_(2)B_(2)O_(2)an efficient catalyst for C–C *** C_(1)and C_(2)chemicals,ethanol is predicted to be the primary ***,by charge and bond analysis,it is unraveled that there exist significantly more unbonded electrons in the C atom of intermediate*COH than other C_(1)intermediates,which is responsible for the facile C–C *** an atomic scale,this work provides microscopic insight into C–C coupling process and suggests Mo_(2)B_(2)O_(2)a promising catalyst for electrochemical CO reduction to C_(2)chemicals.

关键词： C_(2)chemicals C-C coupling density-functional theory MBene Mo2B2O2

东非地区中低温敏化技术生产乳化炸药的组分与性能分析

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爆破器材 2020年第5期49卷 42-46页

作者：孙永江江利民中国万宝工程有限公司北京100052

利用东非地区某乳化炸药生产线实际运行的经验,研究了在东非地区用中低温敏化技术生产乳化炸药时,水相、油相和敏化剂3个主要组分及种类对乳化炸药性能的影响。调整各组分配比,对比分析炸药的性能,从而得出最优配方。结果表明,乳化炸药... 详细信息

利用东非地区某乳化炸药生产线实际运行的经验,研究了在东非地区用中低温敏化技术生产乳化炸药时,水相、油相和敏化剂3个主要组分及种类对乳化炸药性能的影响。调整各组分配比,对比分析炸药的性能,从而得出最优配方。结果表明,乳化炸药的最佳配方:水、油相质量比为93.56.5,水的质量分数控制在10.0%~10.5%之间,水相体系中硝酸钠质量分数控制在8.0%~8.5%之间,敏化体系中亚硝酸钠占总质量的0.09%,体积分数为85%的磷酸占总质量的0.0475%。通过技术控制手段,在东非地区利用中低温敏化技术可以生产出性能优良的乳化炸药。

关键词：乳化炸药东非地区中低温敏化组分性能影响

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基于层次分析法的配电网能效指标体系

电力系统自动化 2013年第21期37卷 146-150,195页

作者：杨小彬李和明尹忠东蒋利民孟珺遐姜喆新能源电力系统国家重点实验室华北电力大学北京市102206 中国电力科学研究院北京市100192

在配电网节能指标研究现状的基础上,依据相关标准规范,兼顾实际的可操作性,建立了一套配电网能效指标体系。构建的指标体系涵盖了配电网规划、设备参数及设备运行状态等评价指标,采用层次分析法确定各单项指标权重,结合单项指标状态值,... 详细信息

在配电网节能指标研究现状的基础上,依据相关标准规范,兼顾实际的可操作性,建立了一套配电网能效指标体系。构建的指标体系涵盖了配电网规划、设备参数及设备运行状态等评价指标,采用层次分析法确定各单项指标权重,结合单项指标状态值,获得被评估配电网综合能效分值,找出配电网能效薄弱环节。建立的指标体系有利于配电网节能潜力挖掘,协助节能技改资金配置优化,助推配电网能效水平的提升。运用该指标体系评估某省电力公司配电网,综合评估结果与实际配电网能效情况一致,验证了指标体系的有效性和实用性。

关键词：层次分析法配电网指标体系

UHPLC测定芎菊上清丸中9种成分含量及化学模式分析

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中国现代应用药学 2019年第23期36卷 2936-2942页

作者：郭守斌江希连江丽敏宋兴发连云港市第一人民医院药学部

目的建立UHPLC波长切换法同时测定芎菊上清丸中9种成分的含量方法。方法采用AgilentEcilipse C18(2.1 mm×100 mm,1.6μm)色谱柱,流动相:甲醇-0.05%磷酸水溶液,梯度洗脱;流速为0.3 mL·min^-1;检测波长:327,237,320,345,278,254 nm;柱温30℃;进样量2μL;并采用SPSS 22.0统计软件对含量测定结果进行主成分分析与聚类分析。结果绿原酸、3,5-二咖啡酰奎宁酸、栀子苷、甘草苷、阿魏酸、盐酸小檗碱、黄芩苷、升麻素苷、5-O-甲基维斯阿米醇苷线性范围分别为4.30~68.80μg·mL^-1(r=0.9990)、6.66~106.56μg·mL^-1(r=0.9992)、7.67~122.72μg·mL^-1(r=0.9994)、4.88~78.08μg·mL^-1(r=0.9991)、2.37~37.92μg·mL^-1(r=0.9991)、6.50~103.92μg·mL^-1(r=0.9992)、8.85~141.60μg·mL^-1(r=0.9994)、0.88~14.08μg·mL^-1(r=0.9997)、0.74~11.92μg·mL^-1(r=0.9993);平均加样回收率(n=9)均在99.42%~103.10%,RSD均<2.0%。主成分分析与聚类分析均可将不同生产厂家的芎菊上清丸很好地分类,且分类结果一致。结论所建立的多成分方法快捷、准确、重复性好,可用于芎菊上清丸的质量控制。

关键词：芎菊上清丸超高效液相色谱法含量测定模式识别

Highly homogeneous zero-index metamaterials make devices more compact and perform better

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Light(Science & Applications) 2024年第5期13卷 806-807页

作者： Wei-Xiang jiang State Key Laboratory of Millimeter Waves School of Information Science and EngineeringSoutheast University210096 NanjingChina

A highly homogeneous microwave zero-index metamaterial based on high-permittivity SrTiO3 ceramics is demonstrated to realize the small-aperture high-directivity *** a novel technique is a remarkable step forward to de... 详细信息

关键词： ceramics SrTiO3 Highly

Drug-Target Interactions Prediction Based on Signed Heterogeneous Graph Neural Networks

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Chinese Journal of Electronics 2024年第1期33卷 231-244页

作者： Ming CHEN Yajian jiang Xiujuan LEI Yi PAN Chunyan JI Wei jiang College of Information Science and Engineering Hunan Normal University School of Computer Science Shaanxi Normal University Faculty of Computer Science and Control Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences Computer Science Department BNU-HKBU United International College

Drug-target interactions(DTIs) prediction plays an important role in the process of drug *** computational methods treat it as a binary prediction problem, determining whether there are connections between drugs and targets while ignoring relational types information. Considering the positive or negative effects of DTIs will facilitate the study on comprehensive mechanisms of multiple drugs on a common target, in this work, we model DTIs on signed heterogeneous networks, through categorizing interaction patterns of DTIs and additionally extracting interactions within drug pairs and target protein pairs. We propose signed heterogeneous graph neural networks(SHGNNs), further put forward an end-to-end framework for signed DTIs prediction, called SHGNN-DTI,which not only adapts to signed bipartite networks, but also could naturally incorporate auxiliary information from drug-drug interactions(DDIs) and protein-protein interactions(PPIs). For the framework, we solve the message passing and aggregation problem on signed DTI networks, and consider different training modes on the whole networks consisting of DTIs, DDIs and PPIs. Experiments are conducted on two datasets extracted from Drug Bank and related databases, under different settings of initial inputs, embedding dimensions and training modes. The prediction results show excellent performance in terms of metric indicators, and the feasibility is further verified by the case study with two drugs on breast cancer.

关键词： Drugs Training Proteins Measurement Message passing Prediction methods Graph neural networks