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Study on Detection of Antibiotic Contents in Water around Landfill Sites

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Agricultural Biotechnology 2024年第2期13卷 33-37页

作者： Sha FENG Dandan LIU Juan LUO Qing LI tao mo Zheng LIU Xiaonan ZOU Guangzhou GRG Metrology&Test(Hunan)Co. Ltd.Changsha 410007China Anhua Administration for Market Regulation Yiyang 413500China Guizhou Engineering Vocational College Tongren 565200China

[Objectives] An ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established for simultaneous determination of 26 antibiotics in the water around landfills. [Methods] After an HLB solid-phase extraction column was activated, and a water sample, which was adjusted with phosphoric acid to a pH of (2±0.5) and added with 500 mg of disodium EDTA, was loaded, and 5 ml of water and 20% methanol water was added for washing. Next, 10 ml of elution solution was added for elution, and the collected eluate was evaporated under reduced pressure at 40 ℃ to near dryness, and 1 ml of reconstitution solution was added to a constant volume. An ACQUITY UPLC BEH C18 (100 mm×2.1 mm, 2.6 μm) chromatographic column was adopted for LC separation by gradient elution with 0.1% formic acid aqueous solution-acetonitrile as the mobile phase. For MS detection, the MRM mode was adopted for collection, and the positive and negative ion modes were switched for simultaneous determination, and the internal standard method was used for quantification. [Results] The correlation coefficient R2 was greater than 0.99 in the linear range of each target substance. The limits of detection ranged from 0.15 to 3.00 ng/L, and the limits of quantitation were between 0.80 and 10.00 ng/L, and the recoveries ranged from 77.9% to 104.85%. [Conclusions] The method has high sensitivity, good accuracy and strong practical value.

关键词： Landfill Antibiotics Ultra high performance liquid chromatography-tandem mass spectrometry

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模型与数据混合驱动的IGBT寿命预测方法

航空学报 2024年第15期45卷 38-49页

作者：田贵双王少萍石健陶模北京航空航天大学自动化科学与电气工程学院北京100191 船舶热能动力全国重点实验室武汉430205 武汉第二船舶设计研究所武汉430205

作为航空逆变器的关键模块,绝缘栅双极晶体管(IGBT)对其安全可靠起着决定性作用。考虑到航空逆变器运行工况复杂,且IGBT是最易失效的器件之一,通过分析航空逆变器IGBT的失效机理和关键特征参数,结合物理解析模型提出一种基于长短时记忆(... 详细信息

作为航空逆变器的关键模块,绝缘栅双极晶体管(IGBT)对其安全可靠起着决定性作用。考虑到航空逆变器运行工况复杂,且IGBT是最易失效的器件之一,通过分析航空逆变器IGBT的失效机理和关键特征参数,结合物理解析模型提出一种基于长短时记忆(LSTM)网络的IGBT寿命预测方法。建立IGBT状态监测数据与结温之间的关系,并由物理解析模型得到IGBT的累积损伤,实现IGBT的实时寿命预测。最后,利用NASA PCoE中心提供的IGBT加速老化实验数据集,开展寿命预测模型的验证,结果表明LSTM网络结合累积损伤模型能够有效预测IGBT的寿命,从而有助于提高航空逆变器的可靠性,降低日常维护成本。

关键词：航空逆变器绝缘栅双极晶体管(IGBT) 长短时记忆(LSTM)网络寿命预测累积损伤

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轨道养护机械动力装置高海拔功率恢复研究

工程机械 2024年第2期55卷 71-78,I0004页

作者：莫涛段学能中国铁建高新装备股份有限公司

轨道养护机械为保障铁路线路运营,需要适应平原和高原地区的变化。在高海拔时,柴油发动机进气量不足,产生功率下降等问题,影响机械的使用效率。对样机建立进气模型,针对随着海拔升高进气量需求增加,实际进气量减小的问题,提出改进进气系... 详细信息

轨道养护机械为保障铁路线路运营,需要适应平原和高原地区的变化。在高海拔时,柴油发动机进气量不足,产生功率下降等问题,影响机械的使用效率。对样机建立进气模型,针对随着海拔升高进气量需求增加,实际进气量减小的问题,提出改进进气系统,增加二级增压,以提高进气密度,解决高原功率下降的问题。通过建立二级增压进气模型,计算出随海拔变化的柴油机转速及负荷的压比控制参数,指出对既有动力装置改装电动二级增压系统,能够增加轨道养护机械的海拔适应能力,减弱海拔变化对发动机进气量的影响,解决高海拔地区轨道养护机械动力下降问题。

关键词：电动增压柴油机高海拔轨道养护机械

Evolution of Spiral Waves in Excitable Systems

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Communications in Theoretical Physics 2009年第4期51卷 621-626页

作者： REN Ji-Rong ZHU tao mo Shu-Fan Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

Spiral waves, whose rotation center can be regarded as a point defect, widely exist in various two-dimensional excitable systems. In this paper, by making use of Duan＇s topological current theory, we obtain the charge density of spiral waves and the topological inner structure of its topological charge. The evolution of spiral wave is also studied from the topological properties of a two-dimensional vector field. The spiral waves are found generating or annihilating at the limit points and encountering, splitting, or merging at the bifurcation points of the two-dimensional vector field. Some applications of our theory are also discussed.

关键词： topological current spiral wave bifurcation theory of spiral wave

Knotted Topological Phase Singularities of Electromagnetic Field

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Communications in Theoretical Physics 2008年第11期50卷 1071-1076页

作者： REN Ji-Rong ZHU tao mo Shu-Fan Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

In this paper,knotted objects (RS vortices) in the theory of topological phase singularity in electromagneticfield have been investigated in *** using the Duan's topological current theory,we rewrite the topological currentform of RS vortices and use this topological current we reveal that the Hopf invariant of RS vortices is just the sum ofthe linking and self-linking numbers of the knotted RS ***,the conservation of the Hopf invariant inthe splitting,the mergence and the intersection processes of knotted RS vortices is also discussed.

关键词： knotted optical vortex topological current phase singularity

上气道CT矢状数据在阻塞性睡眠呼吸暂停综合征诊疗中价值及应用

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黑龙江医学 2024年第2期48卷 192-195页

作者：张浩亮郑海垚莫涛广州市第十二人民医院医院广东广州510620

目的:探讨通过上气道CT来了解阻塞性睡眠呼吸暂停综合征(OSAHS)患者呼吸阻塞平面及病情严重程度的方法。方法:51例患者作多导睡眠监测图监测及上气道CT扫描,并行三维重建,测量上气道矢状位中颏下舌骨距离、软腭长度、舌骨平面C4前角距... 详细信息

目的:探讨通过上气道CT来了解阻塞性睡眠呼吸暂停综合征(OSAHS)患者呼吸阻塞平面及病情严重程度的方法。方法:51例患者作多导睡眠监测图监测及上气道CT扫描,并行三维重建,测量上气道矢状位中颏下舌骨距离、软腭长度、舌骨平面C4前角距离及最小生命间隙,同时进行各测量值与体重指数、最低血氧饱和度(LSaO_(2))及呼吸暂停低通气指数(AHI)的相关性分析。结果:颏下舌骨距离与AHI及LSaO_(2)无相关(P>0.05),最小生命间隙(LC)与AHI呈负相关(P0.05);软腭长度与AHI呈正相关(P<0.01),与LSaO_(2)负相关(P<0.01);气道最小面积及舌骨平面C4前角距离与AHI均呈负相关(P<0.01),与LSaO_(2)均呈正相关(P<0.01),结论:上气道矢状位CT中的软腭长度、最小生命间隙、气道最小面积及舌骨平面C4前角距离对OSAHS病情的轻重判别有意义,能快速初步判定其阻塞平面。

关键词：阻塞性睡眠呼吸暂停综合征矢状位上气道CT 阻塞平面

Information space of sensor networks:Lagrangian,energy-momentum tensor,and applications

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Chinese Journal of Aeronautics 2023年第3期36卷 271-284页

作者： mo tao Shaoping WANG Hong CHEN Han PAN Jian SHI Yuwei ZHANG School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China Wuhan Second Ship Design and Research Institute Wuhan 430205China School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

It is a challenge to investigate the interrelationship between the geometric structure and performance of sensor networks due to the increasingly complex and diverse architecture of *** paper presents two new formulations for the information space of sensor networks,including Lagrangian and energy–momentum tensor,which are expected to integrate sensor networks target tracking and performance evaluation from a unified *** proposed method presents two geometric objects to represent the dynamic state and manifold structure of the information space of sensor *** on that,the authors conduct the property analysis and target tracking of sensor *** the best of our knowledge,it is the first time to investigate and analyze the information energy-momentum tensor of sensor networks and evaluate the performance of sensor networks in the context of target *** and examples confirm the competitive performance of the proposed method.

关键词： Energy-momentum tensor Information science Information space Sensor networks Target tracking

塔里木盆地库车坳陷克拉苏西部油气相态特征及控制因素

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天然气地球科学 2024年第9期35卷 1532-1543页

作者：莫涛何志华朱文慧陈承声王媛王云鹏中国石油塔里木油田分公司勘探开发研究院新疆库尔勒841000 中国科学院广州地球化学研究所有机地球化学国家重点实验室广东广州510640 中国科学院大学北京100049

塔里木盆地库车坳陷克拉苏西部博孜—大北地区油气勘探持续获得突破,但油气组成、物性与油气藏类型复杂,存在油气相态与物性分布规律不清、油气相态主要控制因素不明确等问题。系统收集了研究区75口生产井烃类流体数据,分析了凝析油的... 详细信息

塔里木盆地库车坳陷克拉苏西部博孜—大北地区油气勘探持续获得突破,但油气组成、物性与油气藏类型复杂,存在油气相态与物性分布规律不清、油气相态主要控制因素不明确等问题。系统收集了研究区75口生产井烃类流体数据,分析了凝析油的地球化学特征,油气物性参数(密度、黏度、胶质含量、沥青质含量、干燥系数及生产气油比)及其变化规律,根据干燥系数和气油比划分了油气藏类型,恢复了地质条件下的油气相态特征与赋存状态,探讨了相态分布主控地质因素。结果表明:研究区烃类流体总体表现出“东西分段,南北分带”的特征,黏度密度等物性参数整体呈现出由西向东逐渐升高的趋势。油气赋存状态纵向上由深到浅表现为从液相到凝析气相,再到凝析气(湿气)相,最后到气相。油气类型整体上呈环带状分布,挥发性油藏、凝析气藏与湿气藏受侏罗系恰克马克组烃源岩成熟度控制,干气气藏的分布不仅受侏罗系烃源岩成熟度的控制,还受高—过成熟的三叠系烃源岩的共同影响。研究为准确认识克拉苏西部博孜—大北地区油气相态与物性分布规律、油气相态主控因素及未来油气勘探开发部署提供有力的理论支撑。

关键词：克拉苏西部凝析油气油气相态油气物性 PVT模拟

Data-Driven Fault Detection for Nonlinear System:the Implicit model Approach

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Data-Driven Fault Detection for Nonlinear System:the Implici...