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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

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

Preparation and Electrochemical Behaviors of AA-PEGMA Copolymer Film Electrode

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Chemical Research in Chinese Universities 2012年第1期28卷 156-161页

作者： Lü Xue and liu feng-qi College of Chemistry, Jilin University, Changchun 130012, P. R. China College of Chemistry Jilin University Changchun 130012

A new kind of comblike copolymer film composed of acrylic acid-polyethylene glycol monomethyl ether acrylate copolymer（AA-PEGMA copolymer） was successfully synthesized to immobilize hemoglobin（Hb）. FTIR, UV-Vis and CD spectra suggest that Hb kept its original structure in the AA-PEGMA copolymer film without denaturation. A pair of well-defined, quasi-reversible cyclic voltammetric peaks at around –270 mV vs. saturated calomel electrode（SCE） for the Hb Fe（III）/Fe（II） redox couple was observed on the film-modified electrode in phos phate buffer solution（PBS, pH=7.0）. The formal potential of Hb/AA-PEGMA copolymer film-modified electrode is linearly dependent on solution pH with a slope of –46.3 mV/pH, illustrating that one-proton transfer was accompa nied with each electron transfer. Furthermore, the modified electrode displayed electrocatalytic response to the reduc tion of H2O2 with a linear range of 3.5―126 μmol/L and a detection limit of 1.17 μmol/L. In conclusion, the AA-PEGMA copolymer film was proved to be an excellent matrix for the immobilization and electrochemistry of proteins.

关键词： Copolymer film Hemoglobin Comblike polymer Electrochemical behavior

Photoluminescence of Eu^(2+)Doped ZnS Nanocrystals

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Chinese Physics Letters 2000年第8期17卷 609-611页

作者： liu Shu-man GUO Hai-qing ZHANG Zhi-Hua liu feng-qi WANG Zhan-Guo Laboratory of Semiconductor Materials Sciences Institute of SemiconductorsChinese Academy of SciencesBeijing 100083 State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871

Eu^(2+)doped ZnS nanocrystals exhibit new luminescence properties because of the enlarged energy gap of nanocrys talline ZnS host due to quantum confinement *** emission at about 520nm from Eu^(2+)doped ZnS nanocrystals at room temperature is investigated by using photoluminescence emission and excitation *** green emission with long lifetime(ms)is proposed to be a result of excitation,ionization,carriers recapture and recombination via Eu^(2+)centers in nanocrystalline ZnS host.

关键词： spectroscopy. excitation lifetime

Transcriptome analysis of salt-responsive genes and SSR marker exploration in Carex rigescens using RNA-seq

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Journal of Integrative Agriculture 2018年第1期17卷 184-196页

作者： LI Ming-na LONG Rui-cai feng Zi-rong liu feng-qi SUN Yan ZHANG Kun KANG Jun-mei WANG Zhen CAO Shi-hao Grassland Science Department College of Animal Science and TechnologyChina Agricultural University Institute of Animal Science Chinese Academy of Agricultural Sciences Institute of Pratacultural Science Heilongjiang Academy of Agricultural Sciences

Carex rigescens （Franch.） V. Krecz is a wild turfgrass perennial species in the Carex genus that is widely distributed in salinised areas of northern China. To investigate genome-wide salt-response gene networks in C. rigescens, transcriptome analysis using high-throughput RNA sequencing on C. rigescens exposed to a 0.4% salt treatment （Cr_Salt） was compared to a non-salt control （Cr_Ctrl）. In total, 57 742 546 and 47 063 488 clean reads were obtained from the Cr Ctrl and Cr Salt treatments, respectively. Additionally, 21 954 unigenes were found and annotated using multiple databases. Among these unigenes, 34 were found to respond to salt stress at a statistically significant level with 6 genes up-regulated and 28 downregulated. Specifically, genes encoding an EF-hand domain, ZFP and AP2 were responsive to salt stress, highlighting their roles in future research regarding salt tolerance in C. rigescens and other plants. According to our quantitative RT-PCR results, the expression pattern of all detected differentially expressed genes were consistent with the RNA-seq results. Furthermore, we identified 11 643 simple sequence repeats （SSRs） from the unigenes. A total of 144 amplified successfully in the C. rigescens cultivar LOping 1, and 69 of them reflected polymorphisms between the two genotypes tested. This is the first genome-wide transcriptome study of C. rigescens in both salt-responsive gene investigation and SSR marker exploration. Our results provide further insights into genome annotation, novel gene discovery, molecular breeding and comparative genomics in C. rigescens and related grass species.

关键词： salt stress Carex rigescens transcriptome differentially expressed genes SSR markers

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