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POLY(MALEIC ANHYDRIDE-CO-ACRYLIC ACID)/POLY(ETHYLENE GLYCOL)HYDROGELS WITH pH- AND IONIC-STRENGTH-RESPONSES

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Chinese Journal of Polymer Science 2010年第6期28卷 951-959页

作者： Meng Yang Bo-tian liu Ge Gao Xiao-li liu feng-qi liu College of Chemistry and Macdiarmid Laboratory Jilin University Changchun 130012 China

Poly（maleic anhydride-coacrylic acid）,P（MA-AA）,was synthesized by the free-radical copolymerization of maleic anhydride with acrylic acid,and fast responsive pH-sensitive poly（maleic anhydride-co-acrylic acid）/polyethylene glycol,P（MA-AA）/PEG,hydrogels were prepared using PEG as macromolecular cross-linking ***-IR and ~1H-NMR spectrometry were applied to characterize the structure of P（MA-AA）.The influences of pH and ionic strength on the swelling behavior of P（MA-AA）/PEG hydrogels and the swelling-deswelling changes along with the repeated changes between acid and alkali conditions were *** results showed that there was a hundredfold difference in the swelling ratios between the conditions of acid and alkali,and the swelling capability could not be weakened after multiple swelling-deswelling *** results of swelling kinetics demonstrated that the response rate of P（MA-AA）/PEG hydrogels was very fast,because the swelling transition points always occurred at 10 *** pH-responsive hydrogels reported here might be a smart material for potentially applications in many areas,including biosensors,drug-delivery devices and tissue engineering.

关键词： pH-response P(MA-AA) Macromolecular cross-linking agent External cross-linking

Bilateral complete type discoid medial menisci： an adult patient with tears in both knees

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Chinese Medical Journal 2013年第13期126卷 2587-2588页

作者： LU Ying liu feng-qi MENG Hai Department of Orthopaedic Surgery Beijing Friendship Hospital Capital Medcial University Beijing 100050 China

Adiscoid meniscus, found in 1%-5% of the population, .is a human anatomic variant that usually affects thelateral meniscus of the knee. A discoid meniscus is more prone to injury than a normally shaped meniscus. In 1941,1 Cave and Staples first reported discoid medial meniscus. A bilateral discoid medial meniscus is extremely rare. The first case of bilateral discoid medial meniscus was reported by Murdoch in 1956.2 Since then, no more than 20 case reports of bilateral discoid medial menisci have been published to date, and most have been single case reports.3 Treatment of a torn discoid medial meniscus is similar to the treatment of a tom lateral meniscus of the knee. In cases where there is a significant disability, surgical excision may be required. Traditionally, the treatment of choice for symptomatic torn discoid meniscus has been open total or partial meniscectomy. Currently, arthroscopic partial meniscectomy is commonly used. Either meniscectomy or conservative method for treatment of a discoid medial meniscus with no tear is a debatable issue.3 A 39-year-old male was admitted to our hospital for intermittent swelling and pain of his right knee in 1999. He had a history of twisting injury on the affected knee 10 years before the admission, but the symptoms were not significant at that time. However, one year ago, on and off swelling with pain had gradually developed in his right knee, worsening with long distance walking and sports activities. Sometimes he felt that the knee was ＂giving way＂. Due to increasing discomfort interfering with his daily life, he was referred to us by his doctor. Physical examination of the patient＇s right knee showed atrophy of the musculus quadriceps femoris compared to the opposite side, medial tibiofemoral joint line tenderness, a range of motion from , and positive McMurray sign. The patient had no complaints on his opposite knee and physical examination did not reveal any abnormalities. MRI scan showed discoid medial meniscus

关键词： bilateral discoid medial meniscimeniscectomy magnetic resonance imaging arthroscopy

Room-Temperature Continuous-Wave Operation of a Tunable External Cavity Quantum Cascade Laser

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Chinese Physics Letters 2011年第7期28卷 126-128页

作者： ZHANG Jin-Chuan WANG Li-Jun liu Wan-feng liu feng-qi YIN Wen liu Jun-qi LI Lu WANG Zhan-Guo Key Laboratory of Semiconductor Materials Science Institute of SemiconductorsChinese Academy of SciencesBeijing 100083 Department of Electronic Engineering Tsinghua UniversityBeijing 100084

A room-temperature cw operation of a tunable external cavity(EC)quantum cascade laser(QCL)at an emitting wavelength of 4.6µm is ***−compensation combined with two-phonon resonance in an active region design promises low threshold current density.A very low threshold current density of 1.47 kA/cm^(2) for an EC−QCL operated in cw mode is ***-mode cw operation with a side-mode suppression ratio of 20 dB and a wide tuning range of over 110 cm-1 are ***,an even wider tuning range of over 135 cm^(−1) is obtained in pulsed mode at room temperature.

关键词： tuning mode Quantum

Synthesis of Octylmethoxycinamate-silica Core-shell Nanoparticles with Self-templating Method

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Chemical Research in Chinese Universities 2010年第3期26卷 339-343页

作者： ZHANG qing LI Rui ZHAI Yong-ai liu feng-qi GAO Ge College of Chemistry Jilin University Changehun 130021 P. R. China College of Chemistry Daqing Normal University Daqing 163712 P. R. China

t A self-templating method was employed to synthesize core-shell nanoparticles with octylmethoxycinamate（OMC）, a well-known organic UV absorber, as core and nanosilica particles as shell. The characteristic of this method is that the whole process requires neither surface treatment for nanosilica particles nor additional surfactant or stabilizer, and all the reactions could be finished in one-pot, which exempts removing template and reduces reaction steps compared to the conventional process. The morphology, structure, particle size distribution, chemical composition and optical property of OMC-SiO2 nanoparticles were characterized by scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, dynamic light scattering（DLS）, FTIR spectrometry and UV absorption spectrometry, respectively. Experiment results indicate that the resulting OMC-SiO2 nanoparticles were perfectly spherical with smooth particle surfaces, and had clear core-shell structures. The particle size could be tuned by altering reaction conditions. In addition, the mechanism of the self-templating method for forming core-shell nanoparticles was discussed.

关键词： Nanoparticle Silica Octylmethoxycinamate(OMC) Core-shell structure Self-templating method

Continuous-Wave Operation of Terahertz Quantum Cascade Lasers at 3.2 THz

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Chinese Physics Letters 2013年第6期30卷 102-105页

作者： WANG Tao liu Jun-qi CHEN Jian-Yan liu Ying-Hui liu feng-qi WANG Li-Jun WANG Zhan-Guo Key Laboratory of Semiconductor Materials Science Institute of SemiconductorsChinese Academy of SciencesBeijing 100083

We demonstrate continuous-wave(cw)operation of terahertz(THz)quantum cascade lasers emitting at 3.2 THz based on bound-to-continuum active region and semi-insulating surface-plasmon waveguide *** power of 62 mW with a threshold current density of 285 A/cm^(2)is obtained at 10 K from a 130-μm-wide and 1.5-mm-long laser in cw *** cw operation temperature is up to 60 *** pulsed mode,peak optical power more than 100 mW at 10 K and 2.1 mW at 85 K are observed from a 230-μm-wide and 2-mm-long device.

关键词： waveguide Lasers Quantum

High-Power High-Temperature Continuous-Wave Operation of Quantum Cascade Laser at λ~4.6 μm without Lateral Regrowth

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Chinese Physics Letters 2012年第7期29卷 149-151页

作者： LIANG Ping liu feng-qi ZHANG Jin-Chuan WANG Li-Jun liu Jun-qi WANG Zhan-Guo Key Laboratory of Semiconductor Materials Science Institute of SemiconductorsChinese Academy of SciencesBeijing 100083

High-power quantum cascade lasers (λ =4.6 μm) working in continuous wave (cw) up to 90℃ are *** material was grown by solid-source molecular beam epitaxy and processed into narrow conventional ridge geometry without lateral *** cw output power of 850mW at 10℃ and more than 200mW at 90℃were obtained with threshold current densities of 1.34 and 2.47 kA/cm^(2),respectively,for a high-reflectivity-coated 12-μm-wide and 3-mm-long laser.

关键词： Quantum reflectivity narrow

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立式混流泵组电机漏油技术分析与应对微探

广东水利电力职业技术学院学报 2024年第1期22卷 51-53页

作者：蓝桂生石海波刘启峰广东粤港供水有限公司广东深圳518000

针对某立式混流泵组电机漏油严重、运行摆度大、振动大的问题,从电机设计、制造加工以及安装等方面制定了漏油预防与处理方案,通过改进电机设计结构、修复方式和安装工艺,圆满解决了上述问题。该方案贴合设备运行工况,能显著提升泵组运... 详细信息

针对某立式混流泵组电机漏油严重、运行摆度大、振动大的问题,从电机设计、制造加工以及安装等方面制定了漏油预防与处理方案,通过改进电机设计结构、修复方式和安装工艺,圆满解决了上述问题。该方案贴合设备运行工况,能显著提升泵组运行的安全和稳定性,同时可为类似泵组电机漏油故障处理提供借鉴。

关键词：混流泵组电机漏油故障处理

Hybrid pedestrian positioning system using wearable inertial sensors and ultrasonic ranging

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Defence Technology（防务技术） 2024年第3期33卷 327-338页

作者： Lin qi Yu liu Chuanshun Gao Tao feng Yue Yu School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong Kong 999077China

Pedestrian positioning system(PPS)using wearable inertial sensors has wide applications towards various emerging fields such as smart healthcare,emergency rescue,soldier positioning,*** performance of traditional PPS is limited by the cumulative error of inertial sensors,complex motion modes of pedestrians,and the low robustness of the multi-sensor collaboration *** paper presents a hybrid pedestrian positioning system using the combination of wearable inertial sensors and ultrasonic ranging(H-PPS).A robust two nodes integration structure is developed to adaptively combine the motion data acquired from the single waist-mounted and foot-mounted node,and enhanced by a novel ellipsoid constraint *** addition,a deep-learning-based walking speed estimator is proposed by considering all the motion features provided by different nodes,which effectively reduces the cumulative error originating from inertial ***,a comprehensive data and model dual-driven model is presented to effectively combine the motion data provided by different sensor nodes and walking speed estimator,and multi-level constraints are extracted to further improve the performance of the overall *** results indicate that the proposed H-PPS significantly improves the performance of the single PPS and outperforms existing algorithms in accuracy index under complex indoor scenarios.

关键词： Pedestrian positioning system Wearable inertial sensors Ultrasonic ranging Deep-learning Data and model dual-driven

High Power Surface Metal Grating Distributed Feedback Quantum Cascade Lasers Emitting at λ∼8.3 µm

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Chinese Physics Letters 2012年第9期29卷 70-72页

作者： YAO Dan-Yang liu feng-qi ZHANG Jin-Chuan** WANG Li-Jun liu Jun-qi WANG Zhan-Guo Key Laboratory of Semiconductor Materials Science Institute of SemiconductorsChinese Academy of SciencesBeijing 100083

We present a surface metal grating distributed feedback quantum cascade laser emitting atλ~8.3μm and operating above 400 K in pulsed mode.A very high peak power of 463 mW at 290 K and still more than 18 mW at 400 K is achieved for a high-reflectivity-coated 13-μm-wide and 2.5-mm-long ***-mode emission with a high side mode suppression ratio and wide temperature tuning range is *** a high-power single-mode laser with a simple device process is important for practical applications.

关键词： tuning mode Quantum