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Design and experimental validation of a low-impact wing locking/release mechanism based on energy conversion strategy
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作者 Yanbing Wang Honghao Yue +5 位作者 Jun Wu Xueting Pan Fei Yang Yong Zhao Jicheng Liu Xue Bai 《Defence Technology(防务技术)》 2026年第1期241-256,共16页
Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or ... Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or attitude instability,seriously compromising mission reliability.To address this engineering challenge,this paper proposes a multi-point low-impact locking/release mechanism based on the mobility model and energy conversion strategy.Through establishing a DOF constraint framework system,this paper systematically analyzes the energy transfer and conversion characteristics during the wing separation process,reveals the generation mechanism of impact loads,and conducts research on low-impact design based on energy conversion strategy.Building on this foundation,a single-point locking/release mechanism employing parallel trapezoidal key shaft structure was designed,which increases frictional contact time and reduces the energy release rate,thereby achieving low-impact characteristics.The mechanism's performance was validated through physical prototype development and systematic functional testing(including unlocking force,synchronization,and impact tests).Experimental results demonstrate:(1)Under 14 kN preload condition,the maximum unlocking force was only 92.54 N,showing a linear relationship with preload that satisfies the"strong-connection/weak-unlock"design requirement;(2)Wing separation was completed within 46 ms,with synchronization time difference among three separation mechanisms stably controlled within 12-14 ms,proving rapid and reliable operation;(3)The unlocking impact acceleration ranged between 26 and 73 g,below the 100 g design limit,confirming the effectiveness of the energy conversion strategy.The proposed low-impact locking/release mechanism design method based on energy conversion strategy resolves the traditional challenges of high impact and synchronization deficiencies.The synergistic optimization mechanism of"structural load reduction and performance improvement"provides a highly reliable technical solution for wing separable mechanisms while offering novel design insights for wing connection/separation systems engineering. 展开更多
关键词 Hypersonic vehicle Energy conversion strategy Low-impact Wing separation locking/release mechanism
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Locking up Internal Rotation of N-Phenylcarbazole in Advance to Endow Ultralong Room Temperature Phosphorescence(RTP)Afterglows in Polymers
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作者 Zhang Nianshuang Qin Yujing +4 位作者 Wang Shuobo Liang Yu Yang Wenjun Sun Qikun Xue Shanfeng 《有机化学》 北大核心 2025年第11期4178-4184,共7页
Internal rotation of conjugated organic backbone seriously impaired room temperature phosphorescence(RTP),leading to rare realization of ultra-long afterglows with RTP lifetimes over 2 s in non-bibulous polymers.Herei... Internal rotation of conjugated organic backbone seriously impaired room temperature phosphorescence(RTP),leading to rare realization of ultra-long afterglows with RTP lifetimes over 2 s in non-bibulous polymers.Herein,N-(bromophenyl)carbazoles are cyclized to lock up phenyl-carbazol internal rotation in advance and the fused nitrogen hetero-cyclic compounds are doped into poly(methyl methacrylate)(PMMA).The results show that locking up the molecular internal rotation can achieve ultra-long RTP polymers with lifetimes over 2 s,in contrast,the unlocked molecules hardly emit RTP in PMMA.The high-lying triplet excitons can transfer the energy to low-lying organic fluorescent dyes,and the persistent multicolor afterglows including white emission can be readily modulated.This work discloses an effective and extendable dopant molecular strategy for developing high-performance ultra-long organic RTP polymers. 展开更多
关键词 chemical locking internal rotation ultra-long afterglows room temperature phosphorescence(RTP)polymer
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A Simple and Reliable Eccentric Locking Mechanism
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作者 Mengjiao NIU Yong ZHAO Yongliang YUAN 《Mechanical Engineering Science》 2025年第2期34-38,共5页
In view of the time-consuming and unreliable deficiencies of the cross-axis work piece in the clamping process,combined with the working characteristics of the eccentric mechanism,a simple and fast eccentric locking m... In view of the time-consuming and unreliable deficiencies of the cross-axis work piece in the clamping process,combined with the working characteristics of the eccentric mechanism,a simple and fast eccentric locking mechanism is designed.The push rod iquickly driven by the combined action of the handle and the drum,so that the cross shaft work piece can be quickly locked in the axial direction.The eccentric locking mechanism not only has simple operation and convenient maintenance,but also has the characteristics of low manufacturing cost and high life,and has certain reference value for future special fixture design. 展开更多
关键词 cross shaft eccentric mechanism locking mechanism special fixture
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A two-stage injection locking amplifier based on a cavity magnonic oscillator
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作者 Mun Kim Chunlei Zhang +2 位作者 Chenyang Lu Jacob Burgess Can-Ming Hu 《Chinese Physics B》 2025年第6期154-159,共6页
A cavity magnonic oscillator uses the coupling of a planar transmission line oscillator(cavity) and spin excitations(magnons) in a ferrimagnetic material to achieve superior frequency stability and reduced phase noise... A cavity magnonic oscillator uses the coupling of a planar transmission line oscillator(cavity) and spin excitations(magnons) in a ferrimagnetic material to achieve superior frequency stability and reduced phase noise. Like many low phase noise oscillators, a cavity magnonic oscillator faces the challenge that its narrow resonance profile is not well suited for injection locking amplification. This work presents an improved design for such an oscillator configured as an injection locking amplifier(ILA) with an extended lock range. The proposed design features a two-stage architecture, consisting of a pre-amplification oscillator and a cavity magnonic oscillator, separated by an isolator to prevent backward locking.By optimizing the circuit parameters of each stage, the proposed design achieved an order of magnitude increase in lock range, when compared to its predecessors, all while preserving the phase noise quality of the input, making it well-suited for narrowband, sensitive signal amplification. Furthermore, this work provides a method for using oscillators with high spectral purity as injection locking amplifiers. 展开更多
关键词 cavity magnonic oscillator injection locking amplifier
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Slip rate and locking degree of Haiyuan fault zone,northeastern Qinghai-Xizang plateau,based on refined block model and GPS data
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作者 Yang Liu Yuxuan Qiu +2 位作者 Jialiang Liu Yu Zhang Caijun Xu 《Geodesy and Geodynamics》 2025年第5期536-545,共10页
As a major fault in the northeastern Qinghai-Xizang Plateau,the Haiyuan fault zone is important for understanding the regional deformation.Aiming at the differences in the slip rate and locking degree obtained from di... As a major fault in the northeastern Qinghai-Xizang Plateau,the Haiyuan fault zone is important for understanding the regional deformation.Aiming at the differences in the slip rate and locking degree obtained from different studies,this study constructs a refined block model(including Qilian,Alxa,Ordos,Xining,Haiyuan,and Lanzhou blocks)and uses the grid search and simulated annealing methods to invert GPS data for slip rate and locking degree of the Haiyuan fault zone.The results are as follows:(1)The sinistral slip rates in the western,middle,and eastern segments are 4.93-5.22 mm/a,1.52-4.94 mm/a,and 0.43-1.18 mm/a,decreasing eastward on the whole,while the compression rates are 0.45-1.26 mm/a,0.58-2.62 mm/a,and3.52-4.48 mm/a,increasing eastward on the whole.(2)The locking depth of the western segment increases from about 5 km to about 20 km eastward;the middle segment decreases and then increases eastward;the eastern segment concentrates at about 20 km(PHI is about 0.86).(3)The slip deficit is relatively higher in the Lenglongling,Jinqianghe,Maomaoshan,and Liupanshan faults(averaging about 3.42 mm/a,4.16 mm/a,4.23 mm/a,and 3.43 mm/a within 20 km).(4)The Qilian,Alxa,Xining,Lanzhou,and Haiyuan blocks rotate clockwise,while the Ordos block rotates counterclockwise.Additionally,by comparing different block models,the Haiyuan block should be considered independently.The Haiyuan fault zone adjusts surrounding block movements and uplifts Liupanshan mountain tectonically.The results can provide important references for understanding the regional earthquake risk and deformation mechanism. 展开更多
关键词 Haiyuan fault zone Block model locking degree Slip rate
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A two-field mixed formulation with scattered pressure node distribution in element-free Galerkin method for alleviating volumetric locking in hyperelastic materials
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作者 S.Sai Kumar Albert Shaji Nelson Muthu 《Acta Mechanica Sinica》 2025年第10期115-131,共17页
Rubber-like materials that are commonly used in structural applications are modelled using hyperelastic material models.Most of the hyperelastic materials are nearly incompressible,which poses challenges,i.e.,volumetr... Rubber-like materials that are commonly used in structural applications are modelled using hyperelastic material models.Most of the hyperelastic materials are nearly incompressible,which poses challenges,i.e.,volumetric locking during numerical modelling.There exist many formulations in the context of the finite element method,among which the mixed displacementpressure formulation is robust.However,such a displacement-pressure formulation is less explored in meshfree methods,which mitigates the problem associated with mesh distortion during large deformation.This work addresses this issue of alleviating volumetric locking in the element-free Galerkin method(EFGM),which is one of the popular meshfree methods.A two-field mixed variational formulation using the perturbed Lagrangian approach within the EFGM framework is proposed for modelling nearly incompressible hyperelastic material models,such as Neo-Hookean and Mooney-Rivlin.Taking advantage of the meshless nature of the EFGM,this work introduces a unique approach by randomly distributing pressure nodes across the geometry,following specific guidelines.A wide spectrum of problems involving bending,tension,compression,and contact is solved using two approaches of the proposed displacement-pressure node formulation involving regular and irregular pressure node distribution.It is observed that both approaches give accurate results compared to the reference results,though the latter offers flexibility in the pressure nodal distribution. 展开更多
关键词 Volumetric locking Mixed displacement-pressure formulation EFG method Irregular pressure node distribution Hyperelastic materials
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Deltopectoral vs deltoid split approach for proximal humerus fractures treated with locking plate:Our experience
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作者 Calogero Cicio Gianfranco Longo +11 位作者 Vito Pavone Gianluca Testa Rocco Ortuso Giovanni C Salvo Marco Ganci Ignazio Prestianni Alessio Ferrara Antonio Kory Alessandro Pietropaolo Anna M Monachino Enrica R Cuffaro Giacomo Papotto 《World Journal of Orthopedics》 2025年第9期46-55,共10页
BACKGROUND Proximal humerus fractures(PHFs)are common,especially in the elderly,and optimal surgical management remains debated.This study compares clinical,functional,and radiographic outcomes of deltoid split(DS)vs ... BACKGROUND Proximal humerus fractures(PHFs)are common,especially in the elderly,and optimal surgical management remains debated.This study compares clinical,functional,and radiographic outcomes of deltoid split(DS)vs deltopectoral(DP)approaches in PHFs treated with locking plates.AIM To evaluate and compare the clinical,functional,and radiographic outcomes-as well as postoperative complication rates-associated with the DS vs the DP surgical approach in the open reduction and internal fixation(ORIF)of PHFs using locking plate constructs.METHODS A multicenter retrospective study of 120 patients undergoing ORIF for closed Neer type II-IV PHFs between January 2023 and December 2023.Patients were grouped by surgical approach[DS(n=70),DP(n=50)].Outcome measures included Numeric Rating Scale(NRS)for pain,Quick-Disabilities in Arm,Shoulder,and Hand questionnaire(QuickDASH),Constant-Murley score,Short Form Health Survey-12v2,and radiographic alignment.Complication rates were recorded.Statistical significance was defined as P<0.05.RESULTS Early outcomes favored the DS group:(1)Lower NRS(3.1 vs 5.9);(2)Higher Constant-Murley(68.2 vs 50.5);and(3)Better QuickDASH(25.4 vs 37.1).Complication rate was lower in the DS group(1.66%vs 5.81%).Radiographic outcomes were comparable.Long-term results were similar between groups.CONCLUSION While both approaches yield satisfactory long-term outcomes,the DS approach is associated with faster early recovery and fewer complications,supporting its use in selected cases. 展开更多
关键词 Proximal humerus fracture Deltoid split Deltopectoral locking plate Open reduction and internal fixation Functional outcome
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Ti_(3)C_(2)T_(x)-Based Stress Sensing Fiber Modulator for Dichromatic Mode-Locking
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作者 Jing Liu Bin Shen +3 位作者 Yu Wan Lu Wan Chao-Qing Dai Yue-Yue Wang 《Chinese Physics Letters》 2025年第9期50-61,共12页
Fiber optic sensing technology,with its low transmission loss,wide bandwidth,and broad dynamic range,offers significant advantages for high-sensitivity measurements.In this study,a multi-band soliton modulation system... Fiber optic sensing technology,with its low transmission loss,wide bandwidth,and broad dynamic range,offers significant advantages for high-sensitivity measurements.In this study,a multi-band soliton modulation system for stress sensing is proposed,utilizing Ti_(3)C_(2)T_(x)to generate ultrashort pulses.By applying stress to microfibers,dichromatic periodic multisoliton mode-locking at 1530 nm and 1555.2 nm is achieved.Vibrational mechanical stress further modulates cross-phase interactions between solitons,inducing higher-order bound solitons with small-amplitude oscillations.These dynamic processes reveal complex nonlinear optical behaviors and enhance sensing capabilities.Additionally,the feasibility of stable mode-locking of Ti_(3)C_(2)T_(x)in a 1µm multimode cavity is analyzed using the multimode nonlinear Schrodinger equation,and multisoliton states are experimentally demonstrated by integrating a 1µm narrow-linewidth ultrafast multimode laser with a stressed microfiber. 展开更多
关键词 ti c tx mechanical stress applying stress ultrashort pulsesby dichromatic mode locking nonlinear optical behaviors stress sensing ultrashort pulses
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外源6-BA和GA_(3)对甜瓜叶片乙烯释放量、多胺含量及膜脂过氧化的影响
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作者 赵卫星 李晓慧 +4 位作者 高宁宁 康利允 常高正 李海伦 王慧颖 《河南农业科学》 北大核心 2026年第1期132-138,共7页
为明确6-苄基腺嘌呤(6-BA)和赤霉素(GA_(3))调控甜瓜叶片衰老的生理机制并为其在延缓叶片衰老中的应用提供理论依据,以早熟厚皮甜瓜雪彤9号为试材,在设施栽培条件下于开花坐果期分别叶面喷施30 mg/kg 6-BA和20 mg/kg GA_(3),以清水为对... 为明确6-苄基腺嘌呤(6-BA)和赤霉素(GA_(3))调控甜瓜叶片衰老的生理机制并为其在延缓叶片衰老中的应用提供理论依据,以早熟厚皮甜瓜雪彤9号为试材,在设施栽培条件下于开花坐果期分别叶面喷施30 mg/kg 6-BA和20 mg/kg GA_(3),以清水为对照,探讨叶片叶绿素相对含量(SPAD值)、乙烯释放量、多胺含量及过氧化氢酶(CAT)活性、丙二醛(MDA)含量、过氧化氢(H_(2)O_(2))含量和产量的变化。结果表明,外源6-BA和GA_(3)处理后7~42 d,使甜瓜叶片SPAD值较对照提高1.78%~8.04%和0.37%~6.08%,乙烯释放量较对照降低5.12%~28.46%和2.34%~18.80%,同时叶片MDA、H_(2)O_(2)、腐胺(Put)含量也均有不同程度的降低,精胺(Spm)、亚精胺(Spd)含量和CAT活性有所升高,产量分别提高6.70%、4.75%;从整体上来看,2种外源激素处理前期效果较为明显,随时间的推移其作用效果逐渐减弱。综上所述,6-BA和GA_(3)可通过调控甜瓜叶片乙烯释放量、多胺含量和膜脂过氧化程度,提高叶片的抗衰老能力,延缓叶片衰老。 展开更多
关键词 甜瓜 6-BA GA_(3) 乙烯释放量 多胺 膜脂过氧化
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Locking Effect of the Inhomogeneous Tectonic Lenticular Rock Mass in the Internal Geological Structure of the Baige Landslides
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作者 Peng Cao Huiming Tang +3 位作者 Kun Fang Jianhui Deng Zongliang Li Xinming Wu 《Journal of Earth Science》 2025年第4期1663-1681,共19页
In 2018,Baige,Xizang,witnessed two consecutive large-scale landslides,causing significant damage and drawing widespread attention.From March 2011 to February 2018,the Baige landslide exhibited a 50-m displacement with... In 2018,Baige,Xizang,witnessed two consecutive large-scale landslides,causing significant damage and drawing widespread attention.From March 2011 to February 2018,the Baige landslide exhibited a 50-m displacement without complete failure,culminating in a collapse in October 2018.The mechanisms behind its resistance to failure despite substantial deformation and the influence of the complex geo-structure within the tectonic mélange belt remain unclear.To address these questions,this study utilized a multidisciplinary approach,integrating on-site geological field mapping,surface deformation monitoring,multielectrode resistivity method,and deep displacement analysis.The aim was to evaluate the impact of the intricate geo-structure within the tectonic mélange belt on the Baige landslide events.Findings reveal that the landslide's geo-structure consists of structurally fractured,mesh-like rock masses,including heterogeneous lenticular rock masses and intermittent brittle shear zones distributed around the lens-shaped rock masses.The study underscores that the inhomogeneous and weakly deformed lenticular rock masses function as natural locked segments,governing the stability of the Baige landslide.Specifically,the relatively intact and hard granodiorite porphyry play a crucial role in locking the landslide's deformation.Deep displacement analysis indicates that the brittle shear zones act as the sliding surfaces.The progressive destruction of the locked segments and the gradual penetration of brittle shear zones,driven by gravitational potential energy,contribute to the landslide occurrence.This research provides critical insights into the formation mechanisms of large-scale landslides within tectonic mélange belts. 展开更多
关键词 Baige landslides Jinsha River tectonic mélange belt internal geological structure macro-meso-micro scales rock mass strength heterogeneity locked effect mechanisms
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Spin-Momentum Locking Breakdown of Evanescent Electromagnetic Waves in a Metal-Gyromagnetic Interface
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作者 Yidong Zheng Jianfeng Chen +1 位作者 Wenyao Liang Zhi-Yuan Li 《Chinese Physics Letters》 2025年第8期54-68,共15页
Spin-momentum locking is widely regarded as an inherent property of evanescent waves,where the transverse spin angular momentum is intrinsically tied to the wave's polarization.This principle is well established i... Spin-momentum locking is widely regarded as an inherent property of evanescent waves,where the transverse spin angular momentum is intrinsically tied to the wave's polarization.This principle is well established in systems such as surface plasmon polaritons,surface elastic waves,and other evanescent modes.Here,we theoretically unveil an anomalous breakdown of spin-momentum locking in evanescent electromagnetic waves at a metalgyromagnetic interface.We show that the hybrid polarization of the field induces two successive reversals of transverse spin near the interface—directly violating the conventional locking between spin and momentum.As a result,identical chiral sources placed at different heights above the interface excite evanescent waves propagating in opposite directions,defying standard expectations.This discovery challenges the presumed universality of spin-momentum locking and opens new degrees of freedom for controlling wave propagation in photonic and plasmonic systems. 展开更多
关键词 hybrid polarization field evanescent electromagnetic waves evanescent modesherewe transverse spin angular momentum metalgyromagnetic interfacewe spin momentum locking surface plasmon polaritonssurface evanescent waveswhere
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自走式破膜覆土机设计与试验
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作者 赵坤 张富贵 +2 位作者 艾永峰 徐贵富 管彦银 《农机化研究》 北大核心 2026年第4期25-33,共9页
为解决烤烟种植膜上破膜覆土作业无机可用的问题,结合丘陵山区烤烟深沟高垄种植模式和破膜覆土农艺要求,设计并试制了一款具有等株距破膜、垄沟取土和膜上覆土功能的自走式破膜覆土机。对样机关键部件进行了分析与设计,确定了双曲柄五... 为解决烤烟种植膜上破膜覆土作业无机可用的问题,结合丘陵山区烤烟深沟高垄种植模式和破膜覆土农艺要求,设计并试制了一款具有等株距破膜、垄沟取土和膜上覆土功能的自走式破膜覆土机。对样机关键部件进行了分析与设计,确定了双曲柄五连杆鸭嘴式破膜装置、链斗式取土装置和对孔覆土装置的结构与工作参数,解析了核心部件作业机理。田间试验结果表明:当机组前进速度为0.72 km/h、取土装置回转速度为18.6 r/min、入土深度为8 cm时,膜孔全覆土率为97.50%,孔径合格率为85.53%,孔距合格率为81.25%,空穴率为0%,地膜采光面破损程度为37.20 mm/m^(2)。田间性能试验指标均符合国家和行业标准规定,满足设计要求。 展开更多
关键词 烤烟种植 破膜覆土机 自走式 膜上覆土
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低功耗高电源抑制比的锁频环型片上RC振荡器
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作者 阴亚东 吴志伟 +3 位作者 邱学炜 方宇龙 钟杨源 高跃明 《湖南大学学报(自然科学版)》 北大核心 2026年第2期193-199,共7页
本文提出了一种基于惠斯顿电桥的锁频环型片上阻容(RC)振荡器,其主要由惠斯顿电桥、误差放大器、压控振荡器(voltage-controlled oscillator,VCO)、无交叠时钟生成电路以及低压差线性稳压器(low-dropout linear regulator,LDO)等组成.... 本文提出了一种基于惠斯顿电桥的锁频环型片上阻容(RC)振荡器,其主要由惠斯顿电桥、误差放大器、压控振荡器(voltage-controlled oscillator,VCO)、无交叠时钟生成电路以及低压差线性稳压器(low-dropout linear regulator,LDO)等组成.采用惠斯顿电桥通过阻容充放电形式实现VCO输出信号的频率-电压转换;与常规方法相比,惠斯顿电桥节省了芯片面积并提高了频率稳定性.采用LDO为锁频环路核心模块提供稳定电源,有效提升了振荡器的电源抑制能力.采用高阈值MOS管所构成的反相器级联环形振荡器构成VCO;通过将其供电电压设置为低于反相器中N/PMOS阈值电压之和的方式,有效地避免了N/PMOS同时导通而极大地降低了VCO功耗.完成了振荡器的工作原理分析、锁频环小信号模型建模分析及各模块的电路设计;采用CSMC 180 nm BCD工艺完成了流片验证和测试.测试结果表明,在锁频环作用下VCO锁定振荡于1.98 MHz频率而偏离目标频率1%;当电源电压为(4±1.5)V时,其电源灵敏度(line sensitivity)不超过200×10^(-6)/V;在-20~100℃温度范围内,频率温漂不超过3%,对应250×10^(-6)/℃;工作电流仅11.26μA.与同类设计相比,本文所述锁频环型片上RC振荡器具有较低功耗、较高电源抑制能力和较为优良的品质因数(FoM). 展开更多
关键词 RC振荡器 锁频环 惠斯顿电桥
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胫骨外侧平台骨折三种锁定钢板固定方法比较
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作者 方永超 卢遥 +2 位作者 陈鹏涛 陈佳鑫 何毅浪 《中国矫形外科杂志》 北大核心 2026年第3期235-241,共7页
[目的]比较三种锁定钢板治疗胫骨外侧平台骨折的临床疗效。[方法]回顾性分析2019年2月—2024年2月本科开放复位内固定治疗的57例胫骨外侧平台骨折患者的资料。其中,2021年6月前的36例采用传统前外侧锁定钛板固定(传统组);2021年6月后,... [目的]比较三种锁定钢板治疗胫骨外侧平台骨折的临床疗效。[方法]回顾性分析2019年2月—2024年2月本科开放复位内固定治疗的57例胫骨外侧平台骨折患者的资料。其中,2021年6月前的36例采用传统前外侧锁定钛板固定(传统组);2021年6月后,对累及后外侧象限,但后外侧壁未破裂的6例采用新型四钉锁定钛板固定(四钉组),而外侧壁破裂者的15例采用新型五钉锁定钛板固定(五钉组)。比较三组围手术期、随访及影像资料。[结果]所有患者均顺利完成手术,术中无神经血管损伤等并发症。三组患者手术时间、切口长度、术中透视次数、术中失血量及住院时间的差异均无统计学意义(P>0.05)。患者均获随访,随访时间平均(30.8±14.6)个月。与术后3个月相比,末次随访时三组患者VAS评分显著降低(P<0.05),Rasmussen临床评分和膝伸-屈ROM均显著增加(P<0.05),相应时间点三组间上述指标的差异均无统计意义(P>0.05)。影像方面,最前端螺钉弧度新型五钉组<传统钢板组<新型四钉组,差异有统计学意义[°,(44.5±5.9)vs(51.6±7.0)vs(58.3±8.0),P<0.001];最后端螺钉弧度新型四钉组和新型五钉组均显著大于传统钛板组[°,(112.2±5.1)vs(115.8±13.9)vs(96.1±7.6),P<0.001]。螺钉覆盖弧度新型五钉组>新型四钉组>传统钢板组,差异均有统计学意义[°,(71.3±12.3)vs(54.0±10.3)vs(44.5±6.0),P<0.001]。术后即刻Rasmussen评分新型五钉组<传统钢板组<新型四钉组,差异均有统计学意义[分,(13.8±1.4)vs(15.1±1.8)vs(17.7±0.8),P<0.001],末次随访Rasmussen影像评分新型四钉组显著优于传统钢板组[分,(17.3±1.0)vs(15.5±1.8),P<0.001]。[结论]腓骨头上入路新型锁定钛板较前外侧入路传统锁定钛板固定范围更大,固定更为牢靠,操作难度未增加,但放置时需避免钛板被动前移,顶端尽量固定5枚螺钉。 展开更多
关键词 膝关节 胫骨外侧平台骨折 开放复位内固定 锁定钢板
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塔克拉玛干沙漠“锁边”的战略意义与未来展望 被引量:1
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作者 田洪志 王玲娥 《防护林科技》 2026年第1期78-83,共6页
塔克拉玛干沙漠是中国第一大沙漠,其边缘地区长期受到沙漠扩展和沙尘暴的威胁。为应对这些问题,中国自20世纪70年代末便启动了一系列生态恢复与保护工程。2024年11月,塔克拉玛干沙漠“锁边”工程成功实现3046 km生态屏障的全面合龙。这... 塔克拉玛干沙漠是中国第一大沙漠,其边缘地区长期受到沙漠扩展和沙尘暴的威胁。为应对这些问题,中国自20世纪70年代末便启动了一系列生态恢复与保护工程。2024年11月,塔克拉玛干沙漠“锁边”工程成功实现3046 km生态屏障的全面合龙。这一阶段性成果不仅是我国生态治理的重要里程碑,也为保障生态安全、推动强国建设和实现中华民族的永续发展奠定了基础。其战略意义在于实现生态保护与环境恢复,促进经济发展与社会稳定,维护边疆稳定与国家安全,改善交通条件与践行“一带一路”倡议。为巩固这一阶段性成果,从根本上遏制黄沙的蔓延,塔克拉玛干沙漠“锁边”工程将进入提质增效的新阶段,应持续巩固与提升治沙成果,大力发展具有地方特色的沙产业,继续加强治沙的国际合作与交流。 展开更多
关键词 塔克拉玛干沙漠 “锁边”工程 生态治沙 工程治沙 光伏治沙
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钢板联合Nice结内固定治疗锁骨中段骨折
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作者 卢懿明 杨阳 +1 位作者 潘胜红 曾参军 《临床骨科杂志》 2026年第1期63-66,共4页
目的探讨钢板联合Nice结内固定治疗锁骨中段骨折的疗效。方法将84例锁骨中段骨折患者按照是否联合Nice结固定分为对照组(采用钢板内固定治疗,42例)和观察组(采用钢板联合Nice结内固定治疗,42例)。比较两组围手术期指标、骨折愈合时间、... 目的探讨钢板联合Nice结内固定治疗锁骨中段骨折的疗效。方法将84例锁骨中段骨折患者按照是否联合Nice结固定分为对照组(采用钢板内固定治疗,42例)和观察组(采用钢板联合Nice结内固定治疗,42例)。比较两组围手术期指标、骨折愈合时间、肩关节活动度、疼痛VAS评分、并发症发生情况,采用Constant-Murley评分评价肩关节功能。结果患者均获得随访,时间12~15(13.16±0.32)个月。切口长度、术中出血量、手术时间、住院时间、骨折愈合时间观察组均短(少)于对照组(P<0.05)。术后12个月肩关节外旋、内旋、外展上举、前屈上举活动度观察组均大于对照组(P<0.05)。术后6、12个月疼痛VAS评分及Constant-Murley评分观察组均优于对照组(P<0.05)。术后并发症发生率观察组低于对照组(P<0.05)。结论钢板联合Nice结内固定治疗锁骨中段骨折,具有缩短手术时间、减少术中出血量、减轻患者疼痛、改善肩关节功能、促进骨折愈合的优势,疗效满意。 展开更多
关键词 锁骨中段骨折 Nice结 锁定钢板 内固定
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某机构机械锁定优化方法研究
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作者 李伟刚 王紫艺 《船电技术》 2026年第2期13-15,共3页
针对某机构机械锁定后容易发生偏移的问题,从机构安装特点、受力环境、锁紧方式等方面进行了原因分析,在不增加结构复杂性和操作难度的前提下,研究提出横调螺杆采用厌氧胶粘结防松、竖调螺杆采用唐氏螺纹防松或施必牢螺母防松的优化方法... 针对某机构机械锁定后容易发生偏移的问题,从机构安装特点、受力环境、锁紧方式等方面进行了原因分析,在不增加结构复杂性和操作难度的前提下,研究提出横调螺杆采用厌氧胶粘结防松、竖调螺杆采用唐氏螺纹防松或施必牢螺母防松的优化方法,较好解决了插头与插座偏移问题的发生,提高了机构使用的可靠性和工作效率。 展开更多
关键词 机构 偏移 机械锁定 优化
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汉江碾盘山枢纽工程二线船闸通航水流条件优化试验研究
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作者 徐俊锋 赵家强 《水运工程》 2026年第2期137-146,共10页
碾盘山枢纽已实现一期蓄水目标,针对碾盘山枢纽拟建二线船闸265 m设计方案上下游引航道口门区与主航道夹角较大、二线船闸通航水流条件不佳以及坝下河床调整变化造成枯水期航道出浅和航宽不足等问题,通过船闸通航水流条件及自航船模试验... 碾盘山枢纽已实现一期蓄水目标,针对碾盘山枢纽拟建二线船闸265 m设计方案上下游引航道口门区与主航道夹角较大、二线船闸通航水流条件不佳以及坝下河床调整变化造成枯水期航道出浅和航宽不足等问题,通过船闸通航水流条件及自航船模试验,开展碾盘山二线船闸方案优化试验研究。提出拟建二线船闸上游新建430 m导堤、下游进行复式开挖和喇叭口状开槽疏浚及坝下航道整治时低水期封堵左汊的工程措施,优化方案实施后现有一线船闸上下游通航条件有所改善,新建二线船闸通航水流条件较设计方案亦有所改善。船模试验验证表明,船舶通过引航道口门区及连接段时,航向能够保持稳定,舵角、漂距等参数均达标,通航安全性可靠。 展开更多
关键词 船闸 口门区 连接段 通航水流条件
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基于改进二阶LADRC的自适应锁相环策略
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作者 李慧 赵佳琪 范新桥 《电力科学与技术学报》 北大核心 2026年第1期118-129,共12页
针对柔性直流输电系统在电网电压不平衡、频率突变等复杂工况下,传统锁相环(phase-locked loop,PLL)存在动态响应慢、检测精度差、抑制能力不足的问题,提出一种基于改进二阶线性自抗扰控制(linear active disturbance rejection control... 针对柔性直流输电系统在电网电压不平衡、频率突变等复杂工况下,传统锁相环(phase-locked loop,PLL)存在动态响应慢、检测精度差、抑制能力不足的问题,提出一种基于改进二阶线性自抗扰控制(linear active disturbance rejection control,LADRC)的自适应PLL控制策略。该策略采用具有频率反馈回路的交叉解耦双复系数滤波器作为前置滤波环节,实现了电压正、负序分量的提取与分离,并在二阶LADRC输入参考信号处增设一阶前馈微分环节;设计了一种改进的二阶LADRC控制器作为核心环节,精准检测锁定电压正序分量频率与相位;利用PSCAD/EMTDC平台搭建柔性直流电网进行仿真验证。结果表明,所提自适应PLL控制策略动态响应快、抗干扰能力强、对电网频率和相位跟踪精度高,能有效消除电压不平衡与谐波对PLL的影响。 展开更多
关键词 柔性直流输电 电压不平衡 锁相环 线性自抗扰控制 复系数滤波器
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船闸集中输水系统布置与水力学研究综述
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作者 刘本芹 张公略 《人民长江》 北大核心 2026年第1期150-156,164,共8页
集中输水系统是船闸采用最多的输水型式,输水系统布置和相关水力学问题需要重点关注。基于国内外大量研究成果和工程实践资料,从船闸集中输水系统的布置型式、水力特点、消能方式、阀门开启方式以及输水水动力特性等方面,对船闸集中输... 集中输水系统是船闸采用最多的输水型式,输水系统布置和相关水力学问题需要重点关注。基于国内外大量研究成果和工程实践资料,从船闸集中输水系统的布置型式、水力特点、消能方式、阀门开启方式以及输水水动力特性等方面,对船闸集中输水系统研究进展进行了总结与论述,并结合船闸发展趋势对集中输水系统面临的问题与研究方向进行了探讨。今后建议重点围绕大尺度船闸集中输水系统布置技术,省水船闸集中输水系统设计与输水方式,运河或梯级开发通航河流船闸集中输水系统标准化研究等开展深入研究。 展开更多
关键词 集中输水系统 水力特性 消能工 阀门开启方式 船闸
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