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轨下压电叠堆俘能器安装对车轨系统动力性能的影响

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振动与冲击 2024年第12期43卷 248-259页

作者：杜承运王建军金浩汤丽华北京科技大学应用力学系北京100083 东南大学交通学院南京211189 奥克兰大学机械与机械电子工程系新西兰奥克兰1010

压电俘能技术已经在轨道交通领域受到广泛关注,但目前主要侧重于压电俘能器的结构设计。俘能器的安装会在轨道结构中附加新的装置,可能会对车轨系统动力性能产生一定影响,甚至会威胁行车安全。然而,俘能器的安装对车轨系统动力性能的影... 详细信息

压电俘能技术已经在轨道交通领域受到广泛关注,但目前主要侧重于压电俘能器的结构设计。俘能器的安装会在轨道结构中附加新的装置,可能会对车轨系统动力性能产生一定影响,甚至会威胁行车安全。然而,俘能器的安装对车轨系统动力性能的影响鲜有报道。以轨下压电叠堆俘能器为研究对象,建立了车辆-轨道-俘能器耦合系统的动力分析模型,构建了安装单个或多个俘能器下钢轨和道床的垂向振动方程,采用MATLAB软件编写了新型预测-校正积分法程序,给出了理论解答。通过与已有文献的结果对比,验证了程序的正确性。进一步,探究了采用单个和多个安装方式时俘能器的等效刚度对车轨系统动力性能(钢轨位移、钢轨加速度、扣件力和车体加速度)的影响,并评估了等效刚度与列车舒适度的关系。结果表明:当俘能器等效刚度在0~60×10^(6)N/m变化时,随着俘能器等效刚度的增加,两种安装方式的最大钢轨位移减小,钢轨加速度减少,车体加速度几乎保持不变,扣件力减小,列车行驶的舒适度呈现微小变化;当俘能器的等效刚度在0~2×10^(6)N/m选取时,俘能器的安装对车轨系统动力性能影响很小。研究成果为轨下压电叠堆俘能器的设计与安装提供了理论指导。

关键词：压电俘能器车轨系统轨下压电叠堆俘能器动力性能

Erratum to:Tertiary orientation structures enhance the piezoelectricity of MXene/PVDF nanocomposite

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Nano Research 2024年第6期17卷 5761-5761页

In the first page of the original version of this paper,the Received date should be“10 October 2023”instead of“10 October 2013”.

关键词： Tertiary orientation MXene

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肌筋膜触发点的牵伸运动治疗研究进展

当代体育科技 2024年第3期14卷 4-6页

作者：唐笑笑唐利花长沙医学院湖南长沙410000

肌筋膜疼痛综合征患病率逐年增加,流行病学调查显示,95%的慢性疼痛与触发点有关,而通过适当的牵伸运动可使肌纤维被拉伸至正常位置,能有效地灭活触发点,因其操作简便,治疗效果显著,在肌筋膜触发点的治疗方面具有极大的实用价值。因此,... 详细信息

肌筋膜疼痛综合征患病率逐年增加,流行病学调查显示,95%的慢性疼痛与触发点有关,而通过适当的牵伸运动可使肌纤维被拉伸至正常位置,能有效地灭活触发点,因其操作简便,治疗效果显著,在肌筋膜触发点的治疗方面具有极大的实用价值。因此,该研究将主要对牵伸运动在肌筋膜触发点方面的应用进展进行综述,为肌筋膜疼痛综合征的预防与治疗提供了科学的理论依据与实践基础。

关键词：肌筋膜触发点牵伸运动触发点诊断联合治疗

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Experimental investigation of a passive self-tuning resonator based on a beam-slider structure

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Acta Mechanica Sinica 2019年第5期35卷 1079-1092页

作者： Liuding Yu lihua tang Tiejun Yang Power and Energy Engineering College Harbin Engineering UniversityHarbin 150001China Department of Mechanical Engineering University of AucklandAuckland 1010New Zealand

This work investigates a self-tuning resonator composed of a slender clamped-clamped steel beam and a freely movable *** clamped-clamped beam exhibits hardening nonlinearity when it vibrates in large amplitude,providing a broad bandwidth of dynamic *** moving slider changes the mass distribution of the whole structure,and provides a passive self-tuning approach for capturing the high-energy orbit of the *** the case without inclination,adequate inertial force that mainly depends on the vibration amplitude of the beam and the position of the slider can drive the slider to move from the side toward the centre of the *** movement amplifies the beam response when the excitation frequency is below 37 Hz in our prototyped *** the multi-orbit frequency range(28-37 Hz),the self-tuning and magnification of beam response can be achieved when the slider is initially placed in an appropriate position on the *** the beam is disturbed,however,the desired response in the high-energy orbit can be lost easily and cannot be reacquired without external *** an improved design with a small inclination,the introduced small gravitational component enables the slider to move from the higher side toward the lower side when the beam amplitude is *** property sacrifices the less efficient self-tuning region below 25 Hz,but can enable the beam to acquire and maintain the high-energy orbit response in the multi-orbit frequency range(28-39 Hz),which is resistant to *** proposed resonator in this paper not only broadens the frequency bandwidth of dynamic response,but also enables capture and maintenance of the high-energy orbit in a completely passive *** a passive self-tuning structure presents an advantage in the design of broadband vibration energy-harvesting systems.

关键词： Passive self-tuning Vibration energy harvester Nonlinearity Beam-slider structure

顶空固相微萃取-气相色谱-质谱法测定葡萄酒软木塞中愈创木酚、2,4,6-三氯苯甲醚及2,4,6-三溴苯甲醚的含量

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理化检验（化学分册） 2024年第8期60卷 846-848页

作者：汤丽华高琳刘继辉王紫昕宁夏回族自治区食品检测研究院国家市场监管重点实验室(枸杞和葡萄酒质量安全) 银川750001

软木塞作为葡萄酒传统封口塞沿用至今,软木塞污染是导致葡萄酒感官缺陷的重要来源之一^([1])。愈创木酚(GUA)、2,4,6-三氯苯甲醚(TCA)和2,4,6-三溴苯甲醚(TBA)是软木塞的主要污染物^([2])。GUA是一种具有“烟熏味”“药味”的嗅味物质,... 详细信息

软木塞作为葡萄酒传统封口塞沿用至今,软木塞污染是导致葡萄酒感官缺陷的重要来源之一^([1])。愈创木酚(GUA)、2,4,6-三氯苯甲醚(TCA)和2,4,6-三溴苯甲醚(TBA)是软木塞的主要污染物^([2])。GUA是一种具有“烟熏味”“药味”的嗅味物质,其感官阈值很低;GUA是微生物污染后的代谢产物,大部分由酸土脂环酸芽孢杆菌和酸热脂环酸芽孢杆菌降解软木塞中香草酸产生^([3])。

关键词：脂环酸芽孢杆菌溴苯顶空固相微萃取愈创木酚三氯苯软木塞微生物污染香草酸

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腹针联合穴位埋线治疗单纯性肥胖患者的效果

中国民康医学 2024年第10期36卷 126-128,138页

作者：唐丽华蒋曼君广西中医药大学附属瑞康医院治未病中心广西南宁530011

目的:观察腹针联合穴位埋线治疗单纯性肥胖患者的效果。方法:选取2020年10月至2022年10月该院收治的120例单纯性肥胖患者进行前瞻性研究,按随机数字表法将其分为对照组和观察组各60例。对照组予以饮食-运动-行为干预,观察组在对照组基... 详细信息

目的:观察腹针联合穴位埋线治疗单纯性肥胖患者的效果。方法:选取2020年10月至2022年10月该院收治的120例单纯性肥胖患者进行前瞻性研究,按随机数字表法将其分为对照组和观察组各60例。对照组予以饮食-运动-行为干预,观察组在对照组基础上予以腹针联合穴位埋线治疗,比较两组临床疗效,治疗前后体质量、体质量指数(BMI)、体脂率、血脂指标[三酰甘油(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)]水平和中医证候积分。结果:观察组治疗总有效率为93.33%(56/60),高于对照组的80.00%(48/60),差异有统计学意义(P<0.05);治疗后,观察组体质量、BMI和体脂率均低于对照组,差异有统计学意义(P<0.05);治疗后,观察组TG、TC、LDL-C水平均低于对照组,差异有统计学意义(P<0.05);治疗后,两组中医证候积分均低于治疗前,且观察组低于对照组,差异有统计学意义(P<0.05)。结论:在饮食-运动-行为干预基础上予以腹针联合穴位埋线治疗单纯性肥胖患者可提高治疗总有效率,降低体质量、BMI、体脂率、血脂指标水平和中医证候积分,效果优于单纯饮食-运动-行为干预。

关键词：腹针穴位埋线单纯性肥胖体质量血脂中医证候积分

利用转录组初步探索曲古抑素A延缓香菇菌丝转色机制

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菌物学报 2024年第6期43卷 59-72页

作者：吴涛鲍大鹏王伟霞仝乐涛李福后唐利华江苏海洋大学海洋食品与生物工程学院江苏连云港222005 上海市农业科学院食用菌研究所上海201403

组蛋白去乙酰化是最重要的表观遗传修饰之一,在发育中起着多种作用,但组蛋白去乙酰化在香菇中的详细功能和机制尚不清楚。本研究使用广泛的去乙酰化抑制剂(HDACi)曲古抑素A(TSA)来确定组蛋白去乙酰化对香菇发育过程的作用。通过香菇菌... 详细信息

组蛋白去乙酰化是最重要的表观遗传修饰之一,在发育中起着多种作用,但组蛋白去乙酰化在香菇中的详细功能和机制尚不清楚。本研究使用广泛的去乙酰化抑制剂(HDACi)曲古抑素A(TSA)来确定组蛋白去乙酰化对香菇发育过程的作用。通过香菇菌包的培养,观察到外源性应用TSA能够抑制香菇后熟转色的进程。随后,我们进行了转录组学分析以揭示潜在的机制。数据显示,TSA处理产生393个差异表达基因,这些基因主要富集于次生代谢物的生物合成、内质网中的蛋白质加工、不同环境中的微生物代谢等途径。通过分析TSA处理和对照组的基因表达差异,发现TSA可能通过影响组蛋白乙酰化水平直接或间接影响细胞色素P450、漆酶,糖蛋白家族等相关基因,从而影响香菇菌丝转色。为认识组蛋白去乙酰化对香菇后熟转色发育的影响提供依据,进一步为香菇工厂化生产缩短周期提供一定的借鉴作用。

关键词：转录组组蛋白去乙酰化香菇转色曲古抑素A

Spatio-temporal variation of net anthropogenic nitrogen inputs in the upper Yangtze River basin from 1990 to 2012

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Science China Earth Sciences 2016年第11期59卷 2189-2201页

作者： WANG Ai tang lihua YANG DaWen LEI HuiMin State Key Laboratory of Hydroscience and Engineering Department of Hydraulic Engineering Tsinghua University

The net anthropogenic nitrogen input(NANI) is an important nutrient source that causes eutrophication in water bodies. Understanding the spatio-temporal variation of NANI is important for regional environment assessment and *** paper calculated NANI in the upper Yangtze River basin(YRB), upstream of the Three Gorges Dam(TGD), from1990 to 2012, and analyzed its spatio-temporal characteristics. Over the past 23 years of the study, the average annual NANI increased from 3200 kg N km^(-2) to 4931 kg N km^(-2). The major components were fertilizer N application, atmospheric N deposition,and net food and feed N import. In the northwest high mountainous region with a sparse population, the main component was atmospheric N deposition. Fertilizer N application and net food and feed N import were concentrated in the Chengdu Plain because of the high population density and large areas of farmland. This research found that NANI increased with rapid urbanization and increasing population. The Pearson correlation results illustrated that the spatial distributions of NANI and its major components were affected by land cover/use, agricultural GDP and total population. Increasing NANI has been the major cause of the degrading stream water quality over the past 20 years and is becoming a major threat to the water quality of the TGD reservoir.

关键词： Net anthropogenic nitrogen input Yangtze River basin Land use Urbanization Water quality

A hybrid inversion method of damped least squares with simulated annealing used for Rayleigh wave dispersion curve inversion

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Earthquake Engineering and Engineering Vibration 2014年第1期13卷 13-21页

作者： Lu Jianqi Li Shanyou Li Wei tang lihua Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake Administration Heilongjiang Provincial Water Conservancy Hydro Electric InvestigationDesign&Research Institute Earthquake Administration of Xinjiang Uyghur Autonomous Region

Surface wave methods are becoming increasingly popular in many geotechnical applications and in earthquake seismology due to their noninvasive *** surface wave dispersion curves are a crucial step in most surface wave *** inversion methods have been applied to surface wave dispersion curve inversion,including linearized inversion and nonlinearized inversion *** this study,a hybrid inversion method of Damped Least Squares(DLS) with Very Fast Simulated Annealing(VFSA) is developed for multi-mode Rayleigh wave dispersion curve *** synthetic and in situ fi eld data were used to verify the validity of the proposed *** results show that the proposed method is superior to the conventional VFSA method in aiming at global minimum,especially when parameter searching space is adjacent to real values of the *** advantage of the new method is that it retains both the merits of VFSA for global search and DLS for local *** high temperatures,the global search dominates the runs,while at a low temperatures,the local search dominates the ***,at low temperatures,the proposed method can almost directly approach the actual model.

关键词： damped least squares simulated annealing hybrid inversion dispersion curve Rayleigh wave