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框架结构对薄膜体声波谐振器性能提升的研究

电子学报 2024年第2期52卷 407-413页

作者：吴永乐吴昊鹏赖志国蔡洵唐滨杨清华杨雨豪王卫民北京邮电大学集成电路学院北京100876 北京邮电大学电子工程学院北京100876 苏州汉天下电子有限公司江苏苏州215000

本文研究了框架结构(Frame)对薄膜体声波谐振器(Film Bulk Acoustic Resonator,FBAR)提升性能的作用,从两种Frame结构对体声波能量的反射匹配基础理论出发,针对其功能特点,以实验的方式确定了低频和高频多组框架微结构的组合,对多组FBA... 详细信息

本文研究了框架结构(Frame)对薄膜体声波谐振器(Film Bulk Acoustic Resonator,FBAR)提升性能的作用,从两种Frame结构对体声波能量的反射匹配基础理论出发,针对其功能特点,以实验的方式确定了低频和高频多组框架微结构的组合,对多组FBAR进行了版图绘制以及光刻流片,最终通过片上测试得到了所有分组的谐振器性能.对测试得到的性能进行了分组统计筛选,从测试结果来看,经过优选之后的Frame结构分组无论是对低频还是高频FBAR谐振器都具有提升性能的作用.对低频(1.7 GHz附近)FBAR来说,并联谐振品质因数可以提升1000以上.对高频(5.5 GHz附近)FBAR来说,并联谐振品质因数可以提升300以上.对横向寄生模式较强的高频FBAR,优选的Frame结构可以提升谐振器的横向寄生模式抑制,使串联谐振频率之下的阻抗相位波动减少5°以上.

关键词：薄膜体声波谐振器框架结构流片实验阻抗相位波动

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近二十年我国教师素养研究现状、热点及趋势

继续教育研究 2024年第7期 22-29页

作者：杨灵婷于浩陕西师范大学教育学部陕西西安710062

探讨了2003—2023年我国教师素养的发展轨迹、热点和趋势。通过对1 759篇文献的CiteSpace软件分析,揭示了教师素养从初步探索到多元增长的演变。重点在于教师核心素养、专业素养、信息素养和数字素养,特别强调数字化时代的教师信息技术... 详细信息

探讨了2003—2023年我国教师素养的发展轨迹、热点和趋势。通过对1 759篇文献的CiteSpace软件分析,揭示了教师素养从初步探索到多元增长的演变。重点在于教师核心素养、专业素养、信息素养和数字素养,特别强调数字化时代的教师信息技术应用、跨学科和创新思维的重要性。此外,提升乡村教师素养被视为乡村教育发展的关键。突出了立德树人和课程思政在教师素养研究中的重要地位,反映出教育的人文价值。未来,教师素养研究预计将更深入地结合理论和实践,应对全球化和技术化的挑战,为我国教师素养的发展历史和未来方向提供全面视角,对促进教师素养的研究和实践具有重大意义。

关键词：教师素养教师能力 CiteSpace 数字素养

DOMAIN DECOMPOSITION WITH NONMATCHING GRIDS FOR EXTERIOR TRANSMISSION PROBLEMS VIA FEM AND DTN MAPPING

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Journal of Computational Mathematics 2006年第3期24卷 323-342页

作者： Ju-e yang De-hao yu LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

In this paper, we are concerned with a non-overlapping domain decomposition method （DDM） for exterior transmission problems in the plane. Based on the natural boundary integral operator, we combine the DDM with a Dirichlet-to-Neumann （DtN） mapping and provide the numerical analysis with nonmatching grids. The weak continuity of the approximation solutions on the interface is imposed by a dual basis multiplier. We show that this multiplier space can generate optimal error estimate and obtain the corresponding rate of convergence. Finally, several numerical examples confirm the theoretical results.

关键词： Domain decomposition Nature boundary element Nonmatching grids Weakcontinuity D-N alternating Dual basis Projection operator Error estimate.

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智能汽车线控底盘技术的研究与应用

内燃机与配件 2024年第15期 82-84页

作者：杨玉好唐翠微雅安职业技术学院四川雅安625000

随着自动驾驶技术的快速发展,智能汽车线控底盘技术作为其核心组件,对于提升驾驶安全性、舒适性和效率具有重要意义。智能汽车线控底盘技术是一项关键的自动驾驶技术,通过利用先进的传感器、控制算法和通信技术,实现对车辆底盘系统的精... 详细信息

随着自动驾驶技术的快速发展,智能汽车线控底盘技术作为其核心组件,对于提升驾驶安全性、舒适性和效率具有重要意义。智能汽车线控底盘技术是一项关键的自动驾驶技术,通过利用先进的传感器、控制算法和通信技术,实现对车辆底盘系统的精确控制和稳定运行。本文深入探讨了智能汽车线控底盘的原理、关键技术及其在自动驾驶中的应用,并分析了当前面临的挑战和未来的发展趋势[1]。

关键词：智能汽车线控底盘自动驾驶安全性舒适性

丰水城乡接合区流域治理方案:以武汉东西湖区为例

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中国给水排水 2024年第16期40卷 37-41页

作者：范乐毛毅石亚军杨昱昊位文强童阳魏征武汉市政工程设计研究院有限责任公司湖北武汉430023 武汉市海绵城市和综合管廊建设管理站湖北武汉430023

传统水环境治理存在局部化、零散化、线性化、治理效果反复等系列问题,特别是丰水型城乡接合区域,水环境问题更为复杂,具有范围广、种类多、数量大、分散性强等特点。以武汉市东西湖区为研究对象,以系统化流域治理的理念,综合统筹岸上... 详细信息

传统水环境治理存在局部化、零散化、线性化、治理效果反复等系列问题,特别是丰水型城乡接合区域,水环境问题更为复杂,具有范围广、种类多、数量大、分散性强等特点。以武汉市东西湖区为研究对象,以系统化流域治理的理念,综合统筹岸上、水下和上下游的关系,重点从水安全、水环境、水生态三个方面,针对丰水型城市不同开发建设态势下面临的新型水问题,以问题和需求为导向,提出有侧重的治理思路和体系,经过系列工程落地实施,规划区内地表水劣Ⅴ类水质的湖泊全部消除,达到Ⅲ类标准的有5个,Ⅳ类标准的有10个,流域系统治理成效显著,可为同类型城市流域水环境治理提供参考。

关键词：流域系统治理丰水型城乡结合区水环境治理

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龙脑精油化学成分与药理作用研究进展

中国中药杂志 2024年第11期49卷 2863-2870页

作者：黄思琪易畅刘晓轩杨皓宇张良琦唐宇张喜利刘文龙湖南中医药大学药学院湖南长沙410208 中药成药性与制剂制备湖南省重点实验室湖南长沙410208

龙脑樟是我国首次发现的富含右旋龙脑的樟树珍稀新品种,因其具有极高的利用价值,故又被称为植物黄金。龙脑精油是通过蒸馏等方式从龙脑樟的枝、叶、果实等部位提取得到的天然香气成分,主要含有单萜和倍半萜类化合物,具有镇痛、抗炎、抗... 详细信息

龙脑樟是我国首次发现的富含右旋龙脑的樟树珍稀新品种,因其具有极高的利用价值,故又被称为植物黄金。龙脑精油是通过蒸馏等方式从龙脑樟的枝、叶、果实等部位提取得到的天然香气成分,主要含有单萜和倍半萜类化合物,具有镇痛、抗炎、抗氧化、改善认知功能障碍、抑菌和杀虫等多种药理活性。作为龙脑生物医药工业产业中的高附加值产品,龙脑精油在医药领域、化工生产、食品工业等行业有很大的市场潜力。但目前关于其毒理学安全性评价资料尚不完善,其化学成分和药理作用也易受到产地、采收期、提取部位及前处理方法等多种因素的影响而存在差异,导致临床用药的安全性和疗效难以保障,这可能会对龙脑精油的合理有效利用造成一定阻碍。该文总结归纳了国内外相关文献,分析龙脑精油的发展现状,对其化学成分和药理作用进行综合概述,并进一步讨论当前研究存在的局限性和可能的解决方法,期望为龙脑精油的深度开发、临床应用提供参考,进一步推动以龙脑为核心的大健康产业链的形成与发展。

关键词：龙脑樟精油化学成分药理作用研究进展

Management with the insufficient proximal landing zone for endovascular repair in aortic dissection

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Chinese Medical Journal 2011年第19期124卷 3003-3007页

作者： MA hao yang Hong-yu ZOU Jun-jie ZHANG Xi-wei Department of General Surgery the First Affiliated HospitalNanjing Medical University Department of General Surgery Jiangsu Province Hospital Nanjing Jiangsu 210029 China

Background Sufficient length of the proximal landing zone （PLZ） is the key for a successful thoracic endovascular aortic repair （TEVAR） of an aortic lesion. The aim of this research was to investigate the safety, feasibility, efficacy, and problems of endovascular repair for aortic dissection with insufficient *** The clinical data between August 2005 and February 2010 from patients with insufficient PLZ for endovascular repair of aortic dissection were retrospectively reviewed. According to the classification proposed by Ishimaru, aortic zone 0 was involved in 3 cases, zone 1 in 10 cases, and zone 2 in 11 cases. A hybrid surgical procedure of supraortic debranching and revascularization, directly coverage the orifice of left subclavian artery, or a left common carotid artery chimney graft technique were performed to obtain an adequate proximal aortic landing *** There was no significant difference in risk factors and diameter of the PLZ between Zone 0, Zone 1, and Zone 2. But the length of the PLZ was significantly different in the three groups （P 〈0.01）. There was no significant difference in technical and clinical success rate between the *** The procedure for extending an insufficient PLZ for endovascular repair for aortic arch pathology is feasible and relatively safe. The applicability of TEVAR in such aortic disorders may be expanded.

关键词： endovascular procedures aortic dissection proximal landing zone aorta, thoracic

Changes of paired-pulse evoked responses during the development of epileptic activity in the hippocampus

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第9期12卷 704-711页

作者： Zhou-yan FENG Xiao-jing ZHENG Cong TIAN yang WANG hao-yu XING Ministry of Education Key Lab of Biomedical Engineering College of Biomedical Engineering & Instrument ScienceZhejiang UniversityHangzhou 310027China

Dysfunction of inhibitory synaptic transmission can destroy the balance between excitatory and inhibitory synaptic inputs in neurons,thereby inducing epileptic *** aim of the paper is to investigate the effects of successive excitatory inputs on the epileptic activity induced in the absence of ***-pulse orthodromic and antidromic stimulations were used to test the changes in the evoked responses in the ***(PTX),γ-aminobutyric acid(GABA) type A(GABA A) receptor antagonist,was added to block the inhibitory synaptic transmission and to establish the epileptic *** evoked population spike(PS) was recorded in the CA1 region of the *** results showed that the application of PTX induced a biphasic change in the paired-pulse ratio of PS amplitude.A short latency increase of the second PS(PS2) was later followed by a reappearance of PS2 *** type of depression was observed in both orthodromic and antidromic paired-pulse responses,whereas the GABAergic PS2 depression [called paired-pulse depression(PPD)] during baseline recordings only appeared in orthodromic-evoked *** addition,the depression duration at approximately 100 ms was consistent with a relative silent period observed within spontaneous burst discharges induced by prolonged application of *** conclusion,the neurons may ignore the excitatory inputs and intrinsically generate bursts during epileptic *** depolarization block could be the mechanisms underlying the PPD in the absence of GABA A *** distinct neuronal responses to stimulations during different epileptic stages may implicate the different antiepileptic effects of electrical stimulation.

关键词： Epilepsy Paired-pulse depression γ-Aminobutyric acid(GABA) Picrotoxin(PTX) CA1 region In-vivo

Key processes of carbon cycle and sink enhancement paths in natural wetland ecosystems in China

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Science China Earth Sciences 2024年第8期67卷 2444-2459页

作者： Jinshuai LI Tianxiang hao Meng yang Guirui yu Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Wetland ecosystems have become one of the long-term solutions for mitigating global climate change due to their strong carbon sequestration ***,the key carbon cycle processes in wetland ecosystems still lack a systematic *** the context of wetland protection and restoration,there is still a lack of consensus on the technical pathways to realize carbon sink multiplication in wetland *** this paper,the key processes of carbon cycle,such as photosynthetic carbon uptake,microbial carbon decomposition and carbon deposition and burial,are sorted out and summarized in four major wetland types,namely,swamp and peat wetlands,river and riparian wetlands,lake and lakeshore wetlands,and estuarine and coastal *** on the key processes of carbon cycle,three technological pathways for carbon sink multiplication are proposed,including,vegetation carbon sequestration and sink enhancement technology,soil carbon emission reduction technology and carbon deposition and burial *** key technologies under each pathway are further *** the carbon sink effects of the carbon sink technologies in different wetland types are qualitatively ***,wetland protection and restoration methods in corresponding regions are given in the light of the regional characteristics of wetlands in *** will provide a scientific basis for the strategy of doubling the carbon sinks of China′s wetland ecosystems.

关键词： Wetlands Carbon cycle Carbon sinks Technology pathways Conservation and restoration