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Helmholtz decomposition with a scalar Poisson equation in elastic anisotropic media

petroleum Science 2024年第3期21卷 1597-1610页

作者： Xin-Yu Fang Gang Yao Qing-Qing Zheng Ping-Min zhang Di wu Feng-Lin Niu State key laboratory of {2. resources and Engineering China University of Petroleum(Beijing)Beijing102249China Unconventional petroleum Research Institute China University of Petroleum(Beijing)Beijing102249China Department of mathematics College of ScienceChina University of Petroleum(Beijing)Beijing102249China College of Geophysics China University of Petroleum(Beijing)Beijing102249China Department of Earth Environmental and Planetary SciencesRice UniversityHoustonTX77005UA

P-and S-wave separation plays an important role in elastic reverse-time *** can reduce the artifacts caused by crosstalk between different modes and improve image *** addition,P-and Swave separation can also be used to better understand and distinguish wave types in complex *** present,the methods for separating wave modes in anisotropic media mainly include spatial nonstationary filtering,low-rank approximation,and vector Poisson *** of these methods require multiple Fourier transforms or the calculation of large matrices,which require high computational costs for problems with large *** this paper,an efficient method is proposed to separate the wave mode for anisotropic media by using a scalar anisotropic Poisson operator in the spatial *** 2. problems,the computational complexity required by this method is 1/2.of the methods based on solving a vector Poisson ***,compared with existing methods based on pseudoHelmholtz decomposition operators,this method can significantly reduce the computational *** examples also show that the P and S waves decomposed by this method not only have the correct amplitude and phase relative to the input wavefield but also can reduce the computational complexity significantly.

关键词： Anisotropic media Scalar anisotropic Poisson equation Improved elastic wavefield decomposition

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Regulating surface electron structure of PtNi nanoalloy via boron doping for high‐current‐density Li‐O2.batteries with low overpotential and long‐life cyclability

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Smartmat 2024年第1期5卷 110-120页

作者： Yajun Ding Yuanchao Huang Yuejiao Li Tao zhang Zhong‐Shuai wu State key laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianChina State key laboratory of Silicon {2.terials and School of {2.terials Science and Engineering Zhejiang UniversityHangzhouChina Institute of Advanced Semiconductors Hangzhou Innovation CenterZhejiang UniversityHangzhouChina University of chinese Academy of sciences BeijingChina State key laboratory of High Perfor{2.nce Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghaiChina Dalian National laboratory for Clean Energy Chinese Academy of SciencesDalianChina

The realization of high‐efficiency,reversible,stable,and safe Li‐O2.batteries is severely hindered by the large overpotential and side reactions,especially at high rate ***,rational design of cathode catalysts with high activity and stability is crucial to overcome the terrible issues at high current ***,we report a surface engineering strategy to adjust the surface electron structure of boron(B)‐doped PtNi nanoalloy on carbon nanotubes(PtNiB@CNTs)as an efficient bifunctional cathodic catalyst for high‐rate and long‐life Li‐O2.***,the Li‐O2.batteries assembled with as‐prepared PtNiB@CNT catalyst exhibit ultrahigh discharge capacity of 2.510 ma·h/g and extremely low overpotential of 0.48 V at a high current density of 1000 ma/g,both of which outperform the most reported Pt‐based catalysts ***,our Li‐O2.batteries offer excellent rate capability and ultra‐long cycling life of up to 2.0 cycles at 1000 ma/g under a fixed capacity of 1000 ma·h/g,which is two times longer than those of Pt@CNTs and PtNi@***,it is revealed that surface engineering of PtNi nanoalloy via B doping can efficiently tailor the electron structure of nanoalloy and optimize the adsorption of oxygen species,consequently delivering excellent Li‐O2.battery ***,this strategy of regulating the nanoalloy by doping nonmetallic elements will pave an avenue for the design of high‐performance catalysts for metal‐oxygen batteries.

关键词： B doping bifunctional catalyst Li‐O2.battery low charge overpotential PtNi nanoalloy

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Loose architecture of multi-level massive geospatial data based on virtual quadtree

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Science china(Technological sciences) 2008年第S1期51卷 114-123页

作者： YANG ChongJun,wu Sheng,REN YingChao,FU Li,zhang FuQing,WANG Gang,TAN Jian,LIU DongLin,{2. ChaoJi & LIANG Li State key laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of chinese Academy of sciences and beijing Nor{2.l University,beijing 100101,china 1. State key laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China

This paper proposed a virtual quadtree (VQT) based loose architecture of multi-level massive geospatial data for integrating massive geospatial data dispersed in the departments of different hierarchies in the same sector into a unified GIS (Geographic Information System) platform. By virtualizing the nodes of the quad-tree,the VQT separates the structure of data organization from data storage,and screens the difference between the data storage in local computer and in the re-mote computers in network environment. And by mounting,VQT easily integrates the data from the remote computers into the local VQT so as to implement seam-less integration of distributed multi-level massive geospatial data. Based on that mode,the paper built an application system with geospatial data over 12.0 GB distributed in 12.servers deployed in 12.cities. The experiment showed that all data can be seamlessly rapidly traveled and performed zooming in and zooming out smoothly.

关键词： massive geospatial data virtual quadtree loose architecture

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Transgenic soybean with TaDREB3a gene

Transgenic soybean with TaDREB3a gene

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第十一届全国植物基因组学大会

作者： Miao Liu~1,Zhikun Wang~1,Binbin zhang~1,Xiaoxia wu~1,Youzhi {2.~2.Wenbin Li~(1*) 1 Soybean Research Institute(chinese Education Ministry’s key laboratory of Soybean Biology),Northeast Agricultural University,Harbin 150030,People’s Republic of china 2.Crop Science Institute,chinese Agricultural Academy,beijing,100081

Drought,low temperature and high-salt stresses cause yield losses on as much as half of the world’s irrigated *** and genomic analyses have shown that there are different transcriptional regulatory pathways involved ...

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Petrogenesis and Tectonic Implications of the Paleoproterozoic A-Type Granites in the Xiong’ershan Area along the Southern margin of the North china Craton

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Journal of Earth Science 2024年第2期35卷 416-429页

作者： Jinhong Xu Yuping Jiang Shuli Hu Zhengwei zhang chengquan {2. Chaofei Zheng Xiyao Li Ziru Jin Sensen zhang Yatao Zhou State key laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang550081China University of chinese Academy of sciences Beijing100049China Henan Province Non-ferrous Metals Geological Mineral resources Bureau Zhengzhou450053China Jiangmen Land market Monitoring Center Jiangmen 529000China

Paleoproterozoic A-type granites are widely distributed in the southern margin of the North china Craton(SNCC),providing important information for understanding the Paleoproterozoic tectonic regimes in this *** paper reports newly obtained whole-rock compositions and zircon U-Pb ages for the Tieluping syenogranite porphyry(TLP)and Huoshenmiao alkali granite porphyry(HSM)in the *** from the TLP and HSM have U-Pb ages of 1805±12.and 1792.14 ma,*** ages are taken to date the emplacement of these *** had high total alkali contents(K_(2.O+Na_(2.O>7.13 wt.%),with high 10000×Ga/Al ratios(3.06–3.41)and Zr+Y+Nb+Ce values(709 ppm–910 ppm)as well as high zircon saturation temperatures(864–970℃),indicative of A-type granite *** Y/Nb(1.75–3.32.,Ce/Nb(7.72.9.72.,and Yb/Ta(2.89–5.60)ratios suggested that TLP and HSM belonged to the A2.type *** negative whole rockε_(Nd)(t)values(−8.4 to−6.6)and negative zirconε_(Hf)(t)values(−15.9 to−6.3)confirmed that TLP and HSM were likely generated by the partial melting of an ancient continental ***εHf(t)(−7.4 to+4.0)values of inherited zircons in the TLP suggested that they were derived from the partial melting of Archean basement *** the geochemical similarity of the 1.80 Ga A-type granitoids in the SNCC,we propose that the TLP and HSM were formed in a post-collisional regime that was likely associated with the break-off of the Paleoproterozoic subducted *** of the asthenosphere provided huge heat to generate the regional 1.80 Ga A-type granite in the SNCC.

关键词： Paleoproterozoic A-type granite Post-collisional North china Craton tectonic geochemistry

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Distinguishing the authenticity of anti-freeze liquid and brake fluid by terahertz time-domain spectra technology

Distinguishing the authenticity of anti-freeze liquid and br...

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中国光学学会2.10年光学大会

作者： ZHU Shou-ming 1,ZHAO Kun 1,2,4,TIAN Lu 1,ZHAO Song-qing 1,ZHAO Hui 1,BAO Ri-ma 1,MIAO Qing 1,ZHOU Qing-li 3,SHI Yu-lei 3,ZHAO Dong-mei 3,zhang Cun-lin 3 1.School of Science,china University of petroleum,beijing 102249,china 2.State key laboratory of Heavy Oil Processing,china University of petroleum,beijing 102249,china 3.beijing key laboratory for Terahertz Spectroscopy and Imaging,key laboratory of Terahertz Optoelectronics,Ministry of Education,Department of Physics,Capital Normal University,beijing 100048,china 4.International Center for materials Physics,chinese Academy of sciences,Shenyang 110016,china.

Terahertz time-domain spectra （THz-TDS） technology is a new kind of coherent far infrared spectroscopy measurement technique based on the femtosecond *** optical property and spectroscopy of methanol,anti-freeze liquid and brake fluid are studied based on the THz-TDS in the terahertz *** whether methanol exists in anti-freeze liquid or brake fluid by Using THz-TDS technology is crucial to its *** room temperature,the time-domain spectra and the absorption spectrum in the 0.2.2.5 THz region of these samples are obtained in the environment full of *** Results show that methanol,anti-freeze liquid and brake fluid have significant different absorption spectra in this wave *** absorption peaks of methanol are located at 0.72.THz and 0.35 THz and the main absorption peaks of anti-freeze liquid and brake fluid are located at 0.62.***-TDS Technology can distinguish minor differences in structure and can be applied to physical testing and *** provides a new experimental method for the identification of the organic chemical products and the study of spectrum more wide.

关键词： terahertz methanol anti-freeze liquid brake fluid

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基于突变理论的油气井出砂预测新方法

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西南石油大学学报（自然科学版） 2010年第2期32卷 128-132页

作者：师俊峰刘玉章吴晓东张建军孟宪伟中国石油勘探开发研究院北京海淀100083 中国石油大学石油工程教育部重点实验室北京昌平102249

根据弹塑性力学理论建立了考虑渗流情况下的油气井井眼围岩的势能函数,以该势能函数为基础,应用突变理论的尖点突变模型研究油气井的出砂物理过程,进而建立了出砂预测的全新数学模型,求取无砂生产的临界流速,并在此基础上对影响出砂的... 详细信息

根据弹塑性力学理论建立了考虑渗流情况下的油气井井眼围岩的势能函数,以该势能函数为基础,应用突变理论的尖点突变模型研究油气井的出砂物理过程,进而建立了出砂预测的全新数学模型,求取无砂生产的临界流速,并在此基础上对影响出砂的敏感性因素进行了分析。首次引入突变理论对油气井出砂机理进行分析,建立了无砂生产临界流速的全新求解方法。实例表明该模型的计算结果可靠,敏感性分析表明塑性区的污染是出砂的主要原因。相对以往出砂预测模型,该模型考虑的因素更多,计算结果更可靠。应用突变理论研究油气井出砂机理为出砂预测提供了新的研究方法。

关键词：出砂临界流速突变理论势能函数尖点突变

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Accurate Quantification of Pure Thiacloprid with mass Balance and Quantitative H-NMR

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Journal of Analysis and Testing 2024年第1期8卷 1-8页

作者： Mengling Tu Wei zhang Yunxiao Zhu Wen ma Xiao Li Shukun Zhou Hongmei Li Xianjiang Li key laboratory of Chemical Metrology and Applications on Nutrition and Health for State {2.rket Regulation Division of Metrology in ChemistryNational Institute of MetrologyBeijing 100029China State key laboratory of Heavy Oil Processing College of Chemical Engineering and EnvironmentChina University of PetroleumBeijing 102249China State key laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China

Thiacloprid is the first-generation neonicotinoid insecticide,which is widely used in modern *** materials are essential for sound measurement and traceability of results in chemical *** thiacloprid was comprehensively assessed by two orthonormal methods:mass balance(MB) and quantitative nuclear magnetic resonance spectroscopy(qNMR).From MB,its mass fraction value was 998.4 mg/g with the subtraction of structurally related impurities(99.87%),inorganic impurities(0.006 mg/g),water(0.33 mg/g),and volatile organic solvent(0 mg/g).To guarantee sufficient separation of structurally related purity,peak purity of thiacloprid was evaluated by five points of UV *** the qNMR of hydrogen,its mass fraction value was 995.7 mg/g which was traced to the internal standard(methyl sulfone).Finally,the certified value was assigned to 997 mg/g,together with an expanded uncertainty of 3 mg/g(k=2..This high-purity thiacloprid can be applied to routine monitoring in agriculture and the food fields.

关键词： mass balance Quantitative nuclear magnetic resonance spectroscopy Reference material Thiacloprid

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Transmission of ceftazidime-avibactam-resistant Escherichia coli among pets,veterinarians and animal hospital environment

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Biosafety and Health 2024年第3期6卷 191-198页

作者： Hegen Dai Dongyan Shao Yu Song Qi An Zhenbiao zhang Haixia zhang Siyu {2. Congming wu Jianzhong Shen Yanli Lyu Yang Wang Shizhen ma Zhaofei Xia National key laboratory of Veterinary Public Health Safety College of Veterinary MedicineChina Agricultural UniversityBeijing 100193China key laboratory of Ani{2.l Antimicrobial Resistance Surveillance Ministry of Agriculture and Rural AffairsCollege of Veterinary MedicineChina Agricultural UniversityBeijing 100193China Department of Clinical Veterinary Medicine College of Veterinary MedicineChina Agricultural UniversityBeijing 100193China Shanxi key laboratory for Modernization of TCVM College of Veterinary MedicineShanxi Agricultural UniversityTaiyuan 030801China Ruichen Pet Hospital Group Co. LtdXiamen 361004China

Ceftazidime-avibactam (CZA) is a recently approved combination synthetic β-lactamase inhibitor used in human clinical medicine. Cases of CZA resistance in humans have already been reported, but limited research has investigated CZA resistance in pets. This study explored the prevalence and transmission of CZA-resistant Escherichia coli (CZAREC) among pets, their owners, veterinarians, and the environment in animal hospitals. A total of 5,419 clinical samples were collected from dogs and cats, along with samples from the environment (n = 5,843), veterinarians (n = 557), and pet owners (n = 368) in animal hospitals. From these samples, 760 Escherichia coli (E. coli) isolates were obtained, out of which 60 were identified as CZAREC. These included 34 isolates from the environment (9.14 %, n = 372., three from veterinarians (8.11 %, n = 37), and 2. from animals (6.82.%, n = 337). No CZAREC isolates were found in pet owners. The predominant sequence types of CZARECs were ST156 (n = 2.), ST410 (n = 19) and ST101 (n = 7). Bayesian analysis revealed six clusters comprising 47 isolates from the hospital environment, pets, and veterinaries, displaying genetic relatedness of less than 100 core genome single nucleotide polymorphisms (cgSNPs) between any two isolates in each cluster. Some CZAREC isolates with high genetic similarity persisted in the same animal hospital for four to six months. Moreover, discriminant analysis of principal components indicated that most isolates from different hosts shared a genetic source in the human/dog/cat merged cluster. Overall, evidence of CZARECs transmission was found among pets, the environment, and veterinarians in animal hospitals. The findings emphasize the importance of monitoring CZARECs in the veterinary clinical setting to ensure the health of both pets and humans.

关键词： Ceftazidime-avibactam(CZA) Escherichia coli(E.coli) Pets Animal hospital environment Veterinarians

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The Design of GECAM Scientific Ground Segment

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Research in Astronomy and Astrophysics 2024年第10期24卷 1-10页

作者： Shijie Zheng Liming Song Xiang ma Ping Wang Rui Qiao Yue Huang Xiaoyun Zhao Hongmei zhang Xiaobo Li Mingyu Ge Gang {2. Gongxing Sun Wenxi Peng Ce Cai Wei {2. Yanqi Du Dongya Guo Bing Li Chaoyang Li Jianhui Li Qingxin Li Jing Liang Jiacong Liu Ge Ou Dongli Shi Jingyan Shi Xinying Song Jin Wang Wenshuai Wang Hong wu Shuo Xiao Wang{2. Xue Min Yao Jianying Ye Kai zhang Peng zhang Xiaolu zhang Yanqiu zhang Guoying Zhao Shiyi Zhao Chao Zheng Shaolin Xiong key laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of chinese Academy of sciences Chinese Academy of SciencesBeijing 100049China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Southwest Jiaotong University Chengdu 611756China Xiangtan University Changsha 411105China Qufu Normal University Qufu 273165China

The Gravitational wave burst high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)is a dedicated mission for monitoring high-energy *** we report the design of the GECAM Scientific Ground Segment(GSGS)in terms of the scientific requirements,including the architecture,the external interfaces,the main function,and *** from the analysis and verification results during the commissioning phase,the GSGS functions well and is able to monitor the status of the payloads,adjust the parameters,develop the scientific observation plans,generate the scientific data products,analyze the data,***,the on-orbit operation and scientific researches of GECAM are guaranteed.

关键词： gravitational waves gamma-rays:general telescopes

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