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Preparation and Characterization of Phosphorus Pentafluoride Gas for Lithium Ion Battery Electrolyte Salt

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Chemical Research in Chinese Universities 2009年第6期25卷 791-795页

作者： LIU Jian-wen LI Xin-hai WANG Zhi-xing guo Hua-jun HU qi-yang School of Metallurgical Science and Engineering Central South University Changsha 410083 P. R. China

A novel preparation method of phosphorus pentafluoride（PF5） is introduced in details in the article. Phosphorus pentafluoride is mainly used to synthesize lithium ion battery electrolyte salt. In the experiment mesneproduct- hexafluorophosphoric acid（HPF6） was firstly prepared-from phosphorus pentoxide（P2O5） and anhydrous hydrogen fluoride（HF）, according to the chemical stoichiometrics, the optimum amount of excess HF used was about 60% and the optimum reaction time was 4 h; then HPF6 was dehydrated by oleum with an excess amount of 35%-- 40% which was heated for 40--50 min at 150 ℃; thus HPF6 was decomposed to a mixture of gases containing PF5; impurity gases were removed through condensation in the presence of cooling water at 0 ℃, then PF5 of high purity was eventually prepared. The production was characterized by inffared（IR） spectrometry and gas chromatography-mass spectroscopy-selected ion monitoring（GC-MS-SIM）. Eventual results indicate that PF5 prepared by the novel method has a high target purity and a low amount of impurity and water.

关键词： Hexafluorophosphoric acid Phosphorus pentafluoride Preparation lnfrared spectrum Gas chromatogra- phy-mass spectroscopy-selected ion monitoring

A whispering gallery mode strain sensor based on microtube resonator

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Optoelectronics Letters 2021年第4期17卷 199-204页

作者： LIU Yu YANG Hui-hui LU Yong-le DI Ke guo jun-qi China Chongqing Engineering Research Center of Intelligent Sensing Technology'and Microsystem Chongqing University of Post and TelecommunicationsChongqing 400065China

A novel whispering gallery mode(WGM) strain sensor based on microtube has been proposed, where perceiving strain variations are reported via the dynamical regulation of a whispering gallery mode. The WGMs in the microtube resonator were evanescently excited by a micro-nano fiber fabricated by the fusion taper technique. The structural changes of microtubes under axial strain were simulated with finite element software, and the effect of microtube wall thickness on strain sensitivity was systematically studied through experiments. The experimental results show that the strain sensitivity of thin-walled microtube is found to be 1.18 pm/με and the Q-factor in the order of 4.4× 104. Due to its simple fabrication and easy manipulation as well as good sensing performance, the microtube strain sensor has potential applications in high-sensitivity optical sensing.

关键词： strain mode tube

Overseas immigration of fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), invading Korea and Japan in 2019

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Insect Science 2022年第2期29卷 505-520页

作者： Ming-Fei Wu guo-jun qi Hui Chen Jian Ma Jie Liu Yu-Ying Jiang Gwan-Seok Lee Akira Otuka Gao Hu College of Plant Protection Nanjing Agricultural UniversityNanjing210095 China Guangdong Provincial Key Laboratory of High Technology for Plant Protection/Plant Protection Research Institute Guangdong Academy of Agricultural SciencesGuangzhou510640 China Division of Pest Forecasting China National Agro-Tech Extension and Service CenterBeijing100026 China Department of Agro-food Safety and Crop Protection National Institute of Agricultural SciencesWanju55365 Korea Institute of Agricultural Machinery National Agriculture and Food Research OrganizationTsukuba3058517 Japan

The fall armyworm(FAW),Spodoptera frugiperda(***),spread rapidly in Africa and Asia recently,causing huge economic losses in crop *** armyworm caterpillars were first detected in South Korea and Japan in june ***,the migration timing and path for FAW into the countries were estimated by a trajectory simulation approach implementing the insect's flight *** result showed that FAWs found in both South Korea and Japan were estimated to have come from eastern China by crossing the Yellow Sea or the East China Sea in 10–36 h in three series of *** the first series,FAW moths that arrived on Jeju Island during 22–24 May were estimated to be from Zhejiang,Anhui and Fujian Provinces after 1–2 nights’*** the second series,it was estimated that FAW moths landed in southern Korea and Kyushu region of Japan simultaneously or successively during 5–9 june,and these moths mostly came from Guangdong and Fujian *** FAW moths in the third series were estimated to have immigrated from Taiwan Province onto Okinawa Islands during 19–24 *** these migrations,southwesterly low-level jets extending from eastern China to southern Korea and/or Japan were observed in the northwestern periphery of the western Pacific Subtropical *** results,for the first time,suggested that the overseas FAW immigrants invading Korea and Japan came from eastern and southern *** study is helpful for future monitoring,early warning and the source control of this pest in the two countries.

关键词： Asian migration arena atmospheric circulation Spodoptera frugiperda trajectory analysis windbome insect migration

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高速铁路在黄土高原沟壑区绕避滑坡方案分析

铁道工程学报 2014年第4期31卷 36-40,80页

作者：郭俊奇中铁第一勘察设计院集团有限公司西安710043

研究目的:黄土高原沟壑梁峁区黄土梁蜿蜒起伏,冲沟发育,沟谷深切至第三系地层,使上覆黄土层失稳,形成我国黄土地区分布大面积的巨型滑坡密集地区,滑坡危害严重,直接威胁高速铁路的安全。本文以宝兰客专为例,对绕避滑坡群的线路方案进行... 详细信息

研究目的:黄土高原沟壑梁峁区黄土梁蜿蜒起伏,冲沟发育,沟谷深切至第三系地层,使上覆黄土层失稳,形成我国黄土地区分布大面积的巨型滑坡密集地区,滑坡危害严重,直接威胁高速铁路的安全。本文以宝兰客专为例,对绕避滑坡群的线路方案进行深入分析,确保施工运营安全。研究结论:(1)纵面绕避滑坡的方案和工程措施应依据大量详实的综合地质勘察和外业调查基础资料,实现大大降低隧道施工和运营风险的目的;(2)类似隧道工程中采用纵面绕避滑坡的方案和措施时,应结合地形、地质情况尽量缩短隧道反坡长度,提高隧道最低点高程,解决好洞内防排水问题;(3)隧道下穿滑坡时,应充分考虑在极端异常气象、气候等自然条件作用下,位于隧道上方部分滑体失稳下滑的可能性,以及因人为因素,特别是在隧道工程实施过程中,因工程措施不当造成的局部失稳变形引起的工程滑坡;(4)本文首次提出在黄土高原沟壑区修建隧道以纵面绕避形式穿越黄土高原巨型滑坡群,对今后该区域类似地形、地质、工程条件下的线路选线和工程设置具有很强的指导意义。

关键词：客运专线铁路黄土高原滑坡群线路方案

Abnormal intrinsic brain activity in amnestic mild cognitive impairment revealed by amplitude of low-frequency fluctuation： a resting-state functional magnetic resonance imaging study

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Chinese Medical Journal 2013年第15期126卷 2912-2917页

作者： XI qian ZHAO Xiao-hu WANG Pei-jun guo qi-hao HE Yong Department of Radiology Tongji Hospital of Tongji UniversityShanghai 200065 China Department of Neurology Huashan Hospital of Fudan UniversityShanghai 200040 China State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing 100875 China

Background Previous studies have shown that brain functional activity in the resting state is impaired in Alzheimer＇s disease （AD） patients. However, alterations in intrinsic brain activity patterns in mild cognitive impairment （MCI） patients are poorly understood. This study aimed to explore the differences in regional intrinsic activities throughout the whole brain between aMCI patients and controls. Methods In the present study, resting-state functional magnetic resonance imaging （fMRI） was performed on 18 amnestic MCI （aMCI） patients, 18 mild AD patients and 20 healthy elderly subjects. And amplitude of low-frequency fluctuation （ALFF） method was used. Results Compared with healthy elderly subjects, aMCI patients showed decreased ALFF in the right hippocampus and parahippocampal cortex, left lateral temporal cortex, and right ventral medial prefrontal cortex （vMPFC） and increased ALFF in the left temporal-parietal junction （TPJ） and inferior parietal Iobule （IPL）. Mild AD patients showed decreased ALFF in the left TPJ, posterior IPL （plPL）, and dorsolateral prefrontal cortex compared with aMCI patients. Mild AD patients also had decreased ALFF in the right posterior cingulate cortex, right vMPFC and bilateral dorsal MPFC （dMPFC） compared with healthy elderly subjects. Conclusions Decreased intrinsic activities in brain regions closely related to episodic memory were found in aMCI and AD patients. Increased TPJ and IPL activity may indicate compensatory mechanisms for loss of memory function in aMCI patients. These findings suggest that the fMRI based on ALFF analysis may provide a useful tool in the study of aMCI patients.

关键词： mild cognitive impairment Alzheimer's disease resting-state functional magnetic resonance imaging amplitudeof low-frequency fluctuation compensation

Practical approach for detecting k-nonseparability of multipartite quantum states

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 32-48页

作者： Jie guo Jinchuan Hou Xiaofei qi Kan He College of Mathematics Taiyuan University of Technology School of Mathematics and Statistics Shanxi University Key Laboratory of Complex Systems and Data Science of Ministry of Education Shanxi University

The instantaneous detection of entanglement in quantum states poses a significant challenge in the fields of quantum computation and quantum information, and there are no practical methods or tools to complete this task satisfactorily so far. We propose a sufficient and necessary criterion of k-nonseparability for any n-partite finite or infinite dimensional systems, 2 ≤ k ≤ n. This criterion serves as the foundation for a practical scheme designed to detect entanglement and k-nonseparability across multipartite finite-dimensional systems. To exemplify the application of our scheme, we have developed a software tool that facilitates swift and precise identification of entanglement, k-nonseparability, and genuine entanglement within n-qubit systems, specifically tailored for systems with 2 ≤ n ≤ 4.

关键词： multipartite systems entanglement states entanglement witnesses ${\bm~k}$-nonseparability

Numerical simulation of a neotype fluidic sensing system based on side-polished optical fiber

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Optoelectronics Letters 2020年第4期16卷 262-267页

作者： LIU Yu XIA Bing-qing TAN Hua-yong LU Yong-le DI Ke SONG Ming-xia CHEN Hang ZHANG Yu-lin guo jun-qi Chongqing Municipal Key Laboratory of Photoelectronic Information Sensing and Transmitting Technology Chongqing University of Posts and TelecommunicationsChongqing 400065China

Theoretical design of a neotype fluidic controlling sensor system based on side-polished optical fiber is *** investigations demonstrate that the higher birefringence and resonance coupling can be achieved by flexible design of the polishing shape and depth in the research *** fluidic system is beneficial to selective integration of functional *** material is integrated into the fluidic system,which can achieve a birefringence up to 6.98×10^-5,and the application of Sagnac thermometer in temperature sensing is studied,and a group of dips with different temperature sensitivities would be observed in the transmission spectra,which is about 1.6 nm/℃by ***,by introducing resonant coupling,single mode single polarization at 1310 nm is *** refractive index(RI)response of the sensing system for a low Grange of 1.39-1.37 is approximately linear,and exhibits a sensitivity of 6338 nm/*** results show that the proposed neotype fluidic controlling system can be used as a flexible polarization filter or as a potential two-parameter sensor.

关键词： polarization fiber optical

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前置性文件对铁路建设方案研究的影响分析

铁道标准设计 2014年第7期58卷 163-168页

作者：郭俊奇中铁第一勘察设计院集团有限公司线运处西安710043

铁路建设方案研究是铁路项目前期工作中重要的研究内容之一。随着铁路建设项目立项、审批、建设程序的规范和完善,由相关行业主管部门批准的、影响项目推进的前置性文件,对铁路建设方案的确定有着不可回避的强制性作用。通过分析各前置... 详细信息

铁路建设方案研究是铁路项目前期工作中重要的研究内容之一。随着铁路建设项目立项、审批、建设程序的规范和完善,由相关行业主管部门批准的、影响项目推进的前置性文件,对铁路建设方案的确定有着不可回避的强制性作用。通过分析各前置性文件的主要内容,对铁路建设方案的影响程度,提出铁路建设方案从立项决策、咨询评估、项目建议书批复到可行性研究等阶段,在标准化工作流程中如何深入、细化执行各前置性文件的要求,当前建设方案研究中建议改进的工作方法,提高铁路建设方案在项目后期的可实施性和可操作性。

关键词：前置性文件铁路建设方案分析

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语文学业成就评价标准的缺失与建构

教学与管理 2019年第1期 76-78页

作者：郭俊奇成都大学师范学院成都610106

课程标准是教材编写、教学、评估和考试命题的依据,学生学业成就评价标准是课程标准的重要组成部分。《语文课标》表述的笼统、模糊以及内容标准的缺失等问题,使《语文课标》不具有学生学业成就评价标准的功能,不利于学生学业成就评价... 详细信息

课程标准是教材编写、教学、评估和考试命题的依据,学生学业成就评价标准是课程标准的重要组成部分。《语文课标》表述的笼统、模糊以及内容标准的缺失等问题,使《语文课标》不具有学生学业成就评价标准的功能,不利于学生学业成就评价的有效开展。基于课标,建构由内容标准和表现标准构成的语文学业成就评价标准,是对我国基础教育质量监测评估体系、语文课标的补充和完善,能发挥评价的积极导向功能,提高语文教学效率。

关键词：学业成就语文课标评价标准