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Upconversion Luminescence from Ho3＋ and Yb3＋ Codoped α-NaYF4 Single Crystals

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Chinese Journal of Chemical Physics 2015年第3期28卷 351-354,I0002页

作者： Jia-zhong zhang Hai-ping Xia Shuo Yang yong-zhang jiang Xue-mei Gu Jian-li zhang Hao-chuan jiang Bao-jiu Chen Key laboratory of Photoelectronic Materials Ningbo University Ningbo 315211 China Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Ningbo 315211 China Department of Physics Dalian Maritime University Dalian 116026 China

The Ho3＋/yb3＋ co-doped a-NaYF4 single crystal was grown successfully for the first time by a modified Bridgman method in which KF was used as assisting flux and a large temperature gradient （70-90℃ /cm） of solid-liquid interface was adopted. Upconversion emissions at green -544 nm, red -657 and -751 nm were obtained under 980 nm laser diode excitation. The intensity at -544 nm was much stronger than those of -657 and -751 nm. The mechanisms of the upconversion emissions were investigated by studying the relationship between the upconversion intensity and pump power. The optimized Yb3＋ concentration was about 8.08moi% when Ho3＋ concentration was hold at about 1.0mol%. The results showed that Ho3＋/yb3＋ doped α-NaYF4 single crystal was a possible candidate upconversion material for the green solid-state laser.

关键词： Ho3+/yb3+ a-NaYF4 single crystal Fluorescent intensity Upconversion

Quantum dot vertical-cavity surface-emitting lasers covering the ‘green gap’

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Light(Science & Applications) 2016年第1期5卷 275-281页

作者： Yang Mei Guo-En Weng Bao-Ping zhang Jian-Ping Liu Werner Hofmann Lei-Ying Ying jiang-yong zhang Zeng-Cheng Li Hui Yang Hao-Chung Kuo Department of Electronic Engineering Optoelectronics Engineering Research CenterXiamen UniversityXiamenFujian 361005China Department of Electronic Engineering East China Normal UniversityShanghai 200241China Suzhou Institute of Nano-tech and Nano-bionics Chinese Academy of SciencesSuzhouJiangsu 215123China School of Solid State Physics Technical University of BerlinBerlin 10623Germany Department of Photonics and Institute of Electro-optical Engineering Taiwan Chiao Tung University

Semiconductor vertical-cavity surface-emitting lasers(VCSELs)with wavelengths from 491.8 to 565.7 nm,covering most of the‘green gap’,are *** these lasers,the same quantum dot(QD)active region was used,whereas the wavelength was controlled by adjusting the cavity length,which is difficult for edge-emitting *** with reports in the literature for green VCSELs,our lasers have set a few world records for the lowest threshold,longest wavelength and continuous-wave(CW)lasing at room *** nanoscale QDs contribute dominantly to the low *** emitting wavelength depends on the electron–photon interaction or the coupling between the active layer and the optical field,which is modulated by the cavity *** green VCSELs exhibit a low-thermal resistance of 915 kW^(−1),which benefits the CW *** VCSELs are important for small-size,low power consumption full-color displays and projectors.

关键词： GaN InGaN quantum dot vertical-cavity surface-emitting laser wide-gap semiconductor

Implementation of ITU-T G.729 Speech Codec in IP Telephony Gateway

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Wuhan University Journal of Natural Sciences 2000年第2期5卷 159-163页

作者： HUANG yong feng,zhang jiang ling National Storage System Lab, School of Computer, Huazhong University of Science & Technology, Wuhan 430074,China Huazhong University of Science & Technology National Storage System Lab School of Computer Wuhan China (GRID:grid.33199.31) (ISNI:***)

ITU-T G. 729 is the primarily recommended speech codec by H. 323 standard. This paper describes how to implement G. 729 codec in IP telephony gateway, and goes deep into the programming skills on TMS320C6201 DSP and optimizing methods of program code to reduce the speech processing delay time of G. 729 codec. Due to adopting these optimizing methods and programming skills, we have implemented a high-speed speech codec that can process concurrently 20 voice channels with single TMS320C6201 chip in IP telephony gateway. Finally, the paper analyzes the performance results of ITU-T G. 729 codec based on TMS320C6201.

关键词： Key words ITU T G. 729 IP telephony gateway speech codec

Hydraulic properties and drought response of a tropical bamboo (Cephalostachyum pergracile)

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Plant Diversity 2024年第3期46卷 406-415页

作者： Wanwalee Kongjarat Lu Han Amy Ny Aina Aritsara Shu-Bin zhang Gao-Juan Zhao yong-jiang zhang Phisamai Maenpuen Ying-Mei Li Yi-Ke Zou Ming-Yi Li Xue-Nan Li Lian-Bin Tao Ya-Jun Chen CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYunnan 666303China University of the Chinese Academy of Sciences Beijing 100049China T-STAR Core Team Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYunnan 666303China School of Biology and Ecology University of MaineOronoMEUSA Climate Change Institute University of MaineOronoME 04469USA School of Biological and Chemical Science Pu’er UniversityXueyuan RoadYunnan 665000China Institute of Ecology and Geobotany School of Ecology and Environmental SciencesYunnan UniversityKunmingYunnan 650091China School of Ecology and Environment Southwest Forestry UniversityKunmingYunnan 650224China Yuanjiang Savanna Ecosystem Research Station Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYuanjiangYunnan 653300China

Bamboo plants are an essential component of tropical ecosystems,yet their vulnerability to climate extremes,such as drought,is poorly understood due to limited knowledge of their hydraulic *** pergracile,a commonly used tropical bamboo species,exhibited a substantially higher mortality rate than other co-occurring bamboos during a severe drought event in 2019,but the underlying mechanisms remain *** study investigated the leaf and stem hydraulic traits related to drought responses,including leaf-stem embolism resistance(P50leaf;P50stem) estimated using optical and X-ray microtomography methods,leaf pressure-volume and water-releasing ***,we investigated the seasonal water potentials,native embolism level(PLC) and xylem water source using stable *** found that *** exhibited strong resistance to embolism,showing low P50leaf,P50stem,and turgor loss point,despite its rapid leaf water ***,its leaves displayed greater resistance to embolism than its stem,suggesting a lack of effective hydraulic vulnerability segmentation(HVS) to protect the stem from excessive xylem *** the dry season,approximately 49% of the water was absorbed from the upper 20-cm-deep soil ***,significant diurnal variation in leaf water potentials and an increase in midday PLC from 5.87±2.33% in the wet season to 12.87±4.09%in the dry season were *** summary,this study demonstrated that the rapid leaf water loss,high reliance on surface water,and a lack of effective HVS in *** accelerated water depletion and increased xylem embolism even in the typical dry season,which may explain its high mortality rate during extreme drought events in 2019.

关键词： Climate change Drought Hydraulic safety Hydraulic vulnerability segmentation Stable isotope Tree mortality

Service Model and Architecture for Beyond 3G System

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ZTE Communications 2006年第2期4卷 1-6页

作者： Hu Zheng jiang yong zhang Ping (WTI, Beijing University of Posts and Telecommunications, Beijing 100876, China)

Beyond 3G (B3G) system, the future mobile communication system, is envisioned as a user-centric, open, and convergent information infrastructure capable of providing personalized services. It is extremely important to develop service models and architectures for B3G system. A three-dimension service model is proposed. The dimensions are identified as service support scope, service capability definition, and adaptive feature elements. Then, the hierarchical service architecture for B3G is introduced. The enabling technologies for B3G service architecture are discussed in this paper, such as Virtual Home Environment (VHE), service support environment, service openness, distributed computing, intelligent technology, and profile.

关键词： Service Model and Architecture for Beyond 3G System GPP OSA Gateway UMTS IEEE IMS

A NEW TYPE OF WHEELED INTELLIGENT ULTRASONIC THICKNESS MEASUREMENT SYSTEM

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A NEW TYPE OF WHEELED INTELLIGENT ULTRASONIC THICKNESS MEASU...

SHEAR CIRCUMFERENTIAL GUIDE WAVE IN METAL CYLINDER COMPONENTS

2013全国压电和声波理论及器件技术研讨会

作者： Jin-sheng YANG Xiao-guang ZHAO yong-jiang zhang Zhe CAO China Petroleum Pipeline Inspection Technologies Co. Ltd. National Engineering Laboratory of Oil & Gas Pipeline Transportation & Safety China Petroleum Pipeline Inspection Technologies Co.Ltd. China Petroleum Pipeline Research Institute

In the field of industrial ultrasonic testing,ultrasonic thickness measurement（UTM）is a method of performing non-destructive measurement of the local thickness of a solid element basing on the time taken by the ultrasound wave to return to the surface and it is now regularly utilized in all areas of industrial measurements for its advantage of high penetrating power,high sensitivity and greater accuracy than other non-destructive methods in determining the depth of internal flaws and the thickness of parts with parallel *** are needed to provide effective transfer of ultrasonic wave energy between transducers and parts being *** to the working characteristic of gas pipe,a wheeled ultrasonic thickness measurement system is developed and a kind of special elastic material is used to realize ultrasonic acoustic *** system consists of wheeled thickness measurement probe,pulser and receiver unit,data analysis and storage unit and the interface *** thickness measurement probe is composed of thickness measurement wheel,auxiliary support wheel,slip ring,carbon brush device,proximity switch and other major *** design of thickness measurement wheel uses conventional piezoelectric ultrasonic probe which is installed on the wheel *** wheel hub is casted by special elastic material which can realize ultrasonic acoustic coupling through the tight fitting between the wheel surface and the detected *** auxiliary support wheel casted by polyurethane material is embedded with the metal *** metal block works together with proximity switch to excite the generation of ultrasonic *** paper introduces the working principle and design method of the system.

关键词： Ultrasonic thickness measurement Wheeled probe Pipeline inspection

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SHEAR CIRCUMFERENTIAL GUIDE WAVE IN METAL CYLINDER COMPONENT...

Characterization of Hepatic Drug-metabolizing Activities of Bama Miniature Pigs (Sus Scrofa Domestica): Comparison with Human Enzyme Analogs

2013全国压电和声波理论及器件技术研讨会

作者： Chang-chun QIU Chong-zhen CAO yong-jiang zhang Feng HUO China Petroleum Pipeline Bureau China Petroleum Pipeline Inspection Technologies Co. Ltd.

Axial cracks in metal cylinder components that conventional Nondestructive Testing methods such as magnetic flux leakage,eddy current,magnetic particles are ineffectively *** guide wave due to it’s sensitive to axial defects because the propagation direction is along the circumferential is used to nondestructive testing of cylinder *** acoustic excitation technology,previous research work has focused on the generalized Rayleigh *** the development of science and technology,now days we can excite various type acoustic waves by Electromagnetic Acoustic Technique（EMAT）.Shear guide circumferential waves,reflection or scattering by the axial crack does not produce waveform conversion,has high signal-to-noise ratio,simple detection data *** circumferential guide wave in metal cylinder components are deep studied in this *** results of this study for the design of EMAT coil,Nondestructive Testing data analysis has theoretical guiding sense.

关键词： Shear circumferential guide wave Electromagnetic Acoustic Technique(EMAT) Nondestructive Testing

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Characterization of Hepatic Drug-metabolizing Activities of ...

Distribution of natural killer cell receptors in HIV infected individuals

中国实验动物学会第七届学术年会

作者： Jian Li, yong Liu, jiang-wei zhang, Hong Wei, and Ling Yang

We used various substrates and selective inhibitors of human cytochrome P450 (CYP) isozymes as probes to study the metabolism of liver microsomes from Chinese Bama miniature pigs. Nifedipine oxidation (NOD) and testosterone 6β-hydroxylation (6β-OHT) activities were similar between human liver microsomes and those from Bama miniature pigs. However, compared with those from humans, liver microsomes from Bama miniature pigs showed decreased phenacetin O-deethylation, coumarin 7-hydroxylation, and chlorzoxazone 6-hydroxylation activities, whereas dextromethorphan O-demethylation activity was increased. Ketoconazole selectively inhibited NOD and 6β-OHT activities in microsomes from Bama pigs, and 8-methoxypsoralen and tranylcypromine inhibited coumarin 7-hydroxylation in pig microsomes. However, furafylline and quinidine failed to selectively inhibit phenacetin O-deethylation and dextromethorphan O-demethylation in microsomes from Bama pigs, whereas chlormethiazole more efficiently inhibited coumarin 7-hydroxylation activity than chlorzoxazone 6-hydroxylation in pig microsomes. Our results suggest that liver microsomes from Chinese Bama miniature pigs are similar to those from humans in regard to metabolism of nifedipine and testosterone (both are probe substrates for human CYP3A4). In addition, chemical inhibitors used as specific probes for human P450 enzymes did not always show the same selectivity toward corresponding enzyme activities in liver microsomes from Bama pigs. However, ketoconazole (a potent inhibitor of human CYP3A4) could be used as a selective inhibitor probe for the NOD and 6β-OHT activities in liver microsomes from Chinese Bama miniature pigs.

关键词： 6β-OHT, testosterone 6β-hydroxylation CH, coumarin 7-hydroxylation CYP, cytochrome P450 CZH, chlorzoxazone 6-hydroxylation DMOD, dextromethorphan O-demethylation HPLC, high-performance liquid chromotography NOD, nifedipine oxidation POD, phenacetin O-deethylation UV, ultraviolet

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Chinese Medical Journal 2007年第17期120卷 1544-1548页

作者： jiang yong-jun zhang Zi-ning DIAO Ying-ying GENG Wen-qing DAI Di LIU Jing WANG Ya-nan zhang Min HAN Xiao-xu SHANG Hong Key Laboratory of AIDS Immunology of Ministry of Health FirstHosoital of China Medical University Shenvang 110001 China

Natural killer （NK） cells are bone marrow derived, large granular lymphocytes, comprising approximately 10% to 20% of the mononuclear cell fraction in normal peripheral blood. They form a part of the first line defense mechanism against tumoural and viral spreading^1-4 Unlike T and B cells, NK cells do not require gene rearrangement for assembly of their receptor genes; rather, NK cells discriminate potential target cells based on the levels of self major histocompatibility complex （MHC） class I expression on such cells^5.6 There are two kinds of NK cell receptors^2.7.8 Inhibitory receptors recognize MHC class I molecules and deliver a downregulatory signal that inactivates the lytic machinery of NK cells. Stimulatory receptors expressed by NK cells deliver an activation signal.

关键词： HIV infections NK cells NK cell receptors