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基于地质雷达的隧道超前地质预报技术应用研究

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四川职业技术学院学报 2024年第1期34卷 156-160页

作者：黎一禾成都工贸职业技术学院铁道工程学院四川成都611731

日益增多的山岭隧道多处于复杂工程地质条件的地区,以我国西南地区尤甚.在山岭隧道的勘查和施工过程中,常伴随着岩体破碎、岩溶、岩爆、煤层瓦斯和采空区等特殊工程地质问题单独或者交错出现,带来严重安全隐患,耽误工程进度.超前地质预... 详细信息

日益增多的山岭隧道多处于复杂工程地质条件的地区,以我国西南地区尤甚.在山岭隧道的勘查和施工过程中,常伴随着岩体破碎、岩溶、岩爆、煤层瓦斯和采空区等特殊工程地质问题单独或者交错出现,带来严重安全隐患,耽误工程进度.超前地质预报是山岭隧道施工过程中有效避免此类工程地质问题不可或缺的重要手段之一.本文在简要论述了华蓥山隧道地质条件的基础上,采用地质雷达探测掌子面与开挖掌子面验证相结合的方式,对比分析了山岭隧道施工中超前地质预报技术的应用成效,并进一步提出相应的施工建议.

关键词：山岭隧道地质雷达超前地质预报

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测量系统能力分析在剥离强度测试中的应用

电子质量 2024年第8期 8-12页

作者：韩笑薛微婷李易合中国电子科技集团公司第四十六研究所天津300220

覆铜板是电子产品的基础材料,在电路中起到组件互联的作用,其应用场合决定了覆铜板的铜箔与介质层之间必须具有良好的结合力,主要量化指标是剥离强度,剥离强度对覆铜板的质量有根本性的影响。然而,剥离强度测试是一个较为复杂的破坏性测... 详细信息

覆铜板是电子产品的基础材料,在电路中起到组件互联的作用,其应用场合决定了覆铜板的铜箔与介质层之间必须具有良好的结合力,主要量化指标是剥离强度,剥离强度对覆铜板的质量有根本性的影响。然而,剥离强度测试是一个较为复杂的破坏性测试,受铜箔厚度、介质层组分和微观界面等多种因素影响,并且破坏性测试过程本身难以通过标准样品对测量系统稳定性做出评测。因此,科学地开展测量系统能力分析在覆铜板剥离强度测试过程中非常重要。通过使用专业的数据软件分析量具测量能力Cg,根据各指标水平找出导致测量系统能力低下的原因,针对性开展测量系统的改进,以减少测试误差,提升测量结果的准确性,为覆铜板剥离强度测试的改进方向提供了良好的依据。

关键词：测量系统能力分析覆铜板剥离强度

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2.0 Ga orogenic graphite deposits and associated 13C-enriched meta-carbonate rocks from South China Craton:Implications for global Lomagundi event

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Geoscience Frontiers 2022年第4期13卷 181-192页

作者： yihe li Madhusoodhan Satish-Kumar Sasidharan Kiran Chuanhui Wan Jianping Zheng Institute of Geophysics and Geomatics Hubei Subsurface Multi-scale Imaging Key LaboratoryChina University of GeosciencesWuhan 430074China Department of Geology Faculty of ScienceNiigata UniversityNiigata 950-2181Japan Graduate School of Science and Technology Niigata UniversityNiigata 950-2181Japan Eighth Geological Brigade of Hubei Xiangyang 441000China School of Earth Sciences State Key Laboratory of Geological Processes and Mineral ResourcesChina University of GeosciencesWuhan 430074China

The Lomagundi(-Jatuli)event,characterized by extremely high positive global inorganic carbon isotope excursion at about 2.2 billion years ago,is pivotal in investigating the causes and consequences of great oxygenation event,inventory and sequestration of carbon on the Earth’s surface,evolution of life,and more profoundly tectonic control on Earth’s ***,the reasons that caused the isotopic excursion are not resolved ***,we report the discovery of meta-carbonate rocks with distinct positive carbon isotopic excursion from the Paleoproterozoic continental collision zone of the Kongling Complex,South China *** δ^(13)C_(V-PDB) values for meta-carbonate rocks show positive values in the range from+5.5‰to+11.6‰,whereas the δ^(13)C_(V-PDB) values of associated graphite deposits range from-25.8‰to-9.5‰.Zircon U-Pb-Hf isotopes from zircon-bearing meta-carbonate sample yielded weighted average _(207)Pb/_(206)Pb age of 2001.3±9.5 Ma,with correspondingε_(Hf)(t)range from-7.05 to-3.16,comparable to the values of local 2.9–2.6 Ga basement *** characteristics of meta-carbonate rocks,such as their rare earth element patterns and the trace element parameters of La,Ce,Eu,and Gd anomalies and Y/Ho ratio,suggest that the carbonate deposition took place in passive continental margin in association with large volumes of organic *** extensive graphite deposits from Kongling Complex in South China Craton,their equivalents in the North China Craton and elsewhere across the globe prove that the burial of ^(12)C-enriched organic carbon has eventually resulted in the global enrichment of ^(13)C in the atmospheric CO_(2),which is recorded in the marine carbonate *** mass balance estimates indicate that more than half of the organic carbon was buried during the oceanic ***,the observed global shift could be directly related to the continent collision event in greater China,thus resolving the long-standing paradox of the Lomag

关键词： Positive carbon isotope excursion Lomagundi(-Jatuli)event Kongling Complex South China Craton Marine carbonate

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玻纤处理工艺对玻纤长度分布的影响

玻璃纤维 2024年第4期 17-21页

作者：薛微婷韩笑倪培榛李易合金霞中国电子科技集团公司第四十六研究所天津300220

为了提高聚四氟乙烯(PTFE)基复合材料的力学性能,须在树脂基体中添加玻璃纤维作为增强材料。以玻璃纤维为研究对象,采用一种浆料粉碎设备,通过调节浆料质量分数、设备的转速和粉碎的时间,调控纤维的长度分布,采用鲍尔筛分仪表征纤维的... 详细信息

为了提高聚四氟乙烯(PTFE)基复合材料的力学性能,须在树脂基体中添加玻璃纤维作为增强材料。以玻璃纤维为研究对象,采用一种浆料粉碎设备,通过调节浆料质量分数、设备的转速和粉碎的时间,调控纤维的长度分布,采用鲍尔筛分仪表征纤维的长度分布,研究结果表明:随浆料质量分数的增加、转速的增加、处理时间的延长,截留率均出现先增大后减小的趋势,浆料质量分数、转速、处理时间三者之间两两存在交互作用,浆料质量分数与处理时间、浆料质量分数与转速的交互作用比转速与时间的交互作用更加显著。数据分析与拟合结果显示:浆料质量分数为12.5%、转速为750r/min、处理时间为35s时,预测截留率最高,连续开展多次验证性实验,该条件处理后150μm≤玻纤长度<2mm的截留率可以稳定达到(34.7±2)%,满足工艺使用要求。

关键词：玻纤玻纤长度聚四氟乙烯

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燕麦营养特性及燕麦面条品质改良的研究进展

粮食加工 2024年第4期49卷 83-86页

作者：王杰郑建龙马栎李逸鹤牛雁宁桂亚江苏财经职业技术学院江苏淮安223003 益海嘉里(青岛)食品工业有限公司山东青岛266000

杂粮面制品是目前研究和开发的热点,燕麦作为杂粮的一种也逐渐进入到人们的生活中,对燕麦营养特性、燕麦面条加工工艺以及燕麦面条品质改良进行了综述。指出目前燕麦面条产业中存在的问题,并对燕麦面条的开发和市场前景进行展望。

关键词：燕麦面条营养特性添加剂品质改良

Fast PPP Ambiguity Resolution Using a Sparse Regional Reference Network

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Fast PPP Ambiguity Resolution Using a Sparse Regional Refere...

SIRT2 interacts with DDX24 to promote nasopharyngeal carcinoma growth

第五届中国卫星导航学术年会

作者： yihe li Yang Gao Department of Geomatics Engineering The University of Calgary

Precise point positioning real-time kinematic （PPP-RTK） can achieve fast ambiguity resolution and precise positioning with the satellite fractional cycle biases （FCBs） and atmospheric correction derived from a dense regional reference network. However, the interpolated atmospheric corrections based on a sparse reference network with inter-station distances of more than 100km are not precise enough to facilitate reliable PPP ambiguity resolution. In this contribution, a new method is proposed for fast PPP ambiguity resolution within a sparse regional reference network. First, code biases, FCBs, biased ionospheric and tropospheric delays at the reference stations are estimated with known positioning using the regional sparse reference network data. Then, the biased ionospheric and tropospheric corrections at a user station are generated using a distance-based linear interpolation of the ionospheric and tropospheric delays available at the reference stations. To strengthen the observation model, the interpolated ionospheric and tropospheric delays derived from the sparse network are all considered as pseudo-observations with a given variance-covariance matrix which will be adaptively estimated according to the reference network density to describe the level of the constraint strength. To get a realistic constraint variance, atmospheric constraint variance is estimated with a certain window length. By a proper tuning of the variance-covariance matrix applied for the atmospheric pseudo-observations, the method can adapt any scale of the regional reference network. The ambiguity fixing performance and the resulted position accuracy are assessed with medium and large reference networks. The validation confirms that the new strategy can fix ambiguity within 1 minute for a medium network and within 7 minutes for a larger network while provide centimeter-level positioning solution ambiguity with 20.8 seconds for a medium network and within 71.9 seconds for a larger network.

关键词： PPP-RTK ·Regional sparse reference network·Ionosphere-constraint model·adaptive constraint variance estimation

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BIOCELL 2023年第11期47卷 2445-2452页

作者： HAIYING YUE CHUNHUI WANG HUIJUN ZHU QINGHUA DU JIAN li XUE OU XIANGDE li QIULU ZHONG YITING XIE DANJING LUO yihe li CHUNXIAO liANG XUEMEI XU SONGNAN DU WENQI liU Department of Radiotherapy The Second Affiliated Hospital of Guangxi Medical UniversityNanningChina

Background:Nasopharyngeal carcinoma(NPC)is one of the most prevalent cancers in Southeast *** 2(SIRT2)is a member of the NAD+-dependent deacetylase family and has been shown to play important roles in numerous biological ***,Its function in NPC remains *** primary aim of this study is to clarify the role of SIRT2 in ***:In this research,we examined the effect of SIRT2 silencing on NPC cell proliferation and colony formation using vitro NPC cell ***-immunoprecipitation and mass spectrometry was applied to identify SIRT2-interacting proteins in NPC ***:In comparison to nasopharyngeal epithelial NP69 cells,SIRT2 was up-regulated in multiple NPC cell lines,particularly in CNE2 ***2 knockdown abrogated CNE2 cell proliferation and colony formation,whereas SIRT2 overexpression promoted HNE1 cell proliferation and colony *** SIRT2-interacting proteins were gathered in gene expression and regulation processes including RNA processing and *** the SIRT2-interacting proteins,there were multiple DEAD-box(DDX)family *** note,silencing of DDX24 phenocopied the effect of SIRT2 knockdown on NPC *** of DDX24 restored SIRT2-depleted CNE2 cells to proliferative and colony ***:Our study indicates that SIRT2 can interact with DDX24 to enhance NPC *** clinical relevance of SIRT2 and DDX24 in NPC warrants further investigation.

关键词： Nasopharyngeal carcinoma Sirtuin 2 DDX24 Proliferation

How Do the Nucleons Pack in an Atomic Nucleus?

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World Journal of Nuclear Science and Technology 2014年第4期4卷 237-248页

作者： Xiaodong li Qijun liu Gongyi li yihe li Zengyong Chu Department of Chemistry and Biology College of Science National University of Defense Technology Changsha China

A nuclear structure model of “ring plus extra nucleon” is proposed. For nuclei larger than 4He, protons (P) and neutrons (N) are basically bound alternatively to form a ZP + ZN ring. The ring folds with a “bond angle” of 90° for every 3 continuous nucleons to make the nucleons packed densely. Extra N(‘s) can bind to ring-P with the same “bond angle” and “bond distance”. When 2 or more P’s are geometrically available, the extra N tends to be stable. Extra P can bind with ring N in a similar way when the ratio of N/P like black-white photo and the negative film. Therefore, an identical spin and parity was confirmed for any pair. In addition, the EB/A difference of mirror nuclei pair is nearly a constant of 0.184n MeV. Many other facts can also be easily understood from this model, such as the neutron halo, the unusual stability sequence of 9Be, 7Be and 8Be and so on.

关键词： Nuclear Structure Ring plus Extra Nucleon Model Nuclear Symmetricity

基于点击化学合成含有全氟环丁基芳基醚的ABA三嵌段共聚物

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有机化学 2013年第10期33卷 2148-2154页

作者：李炳臻李义和国防科技大学理学院化学与生物学系长沙410073

由于三氟乙烯基芳基醚单体独特的聚合机理和反应温度,因此难以通过顺序投料法来合成含有全氟环丁基芳基醚结构的嵌段共聚物.我们通过端基修饰的方法在全氟环丁基芳基醚聚合物链端引入叠氮基团,通过点击化学与含有炔基的聚乙二醇相连,制... 详细信息

由于三氟乙烯基芳基醚单体独特的聚合机理和反应温度,因此难以通过顺序投料法来合成含有全氟环丁基芳基醚结构的嵌段共聚物.我们通过端基修饰的方法在全氟环丁基芳基醚聚合物链端引入叠氮基团,通过点击化学与含有炔基的聚乙二醇相连,制备了含有全氟环丁基芳基醚的ABA三嵌段共聚物.

关键词：嵌段共聚物端基偶联法点击化学全氟环丁基芳基醚聚合物