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新纹状体棘神经元的自发放模式
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作者 董金辉 《江苏师范大学学报(自然科学版)》 CAS 1996年第1期52-54,共3页
在细胞水平上,对纹状体棘细胞自发放模式的产生机制进行了综述,并在此基础上作了若干合理推断.
关键词 纹状体 棘细胞 自发放
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Nonlinear Absorption and Low-threshold Two-photon Pumped Amplified Stimulated Emission from FAPbBr_(3) Nanocrystals
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作者 WANG Yajuan TAY Yong Kang Eugene +3 位作者 WANG Fang YU Sheng SUM Tze Chien LIU Wei 《发光学报》 EI CAS CSCD 北大核心 2024年第8期1281-1291,共11页
Formamidinium lead bromide(FAPbBr_(3))nanocrystals(NCs)have been considered to be a good optoelectronic material due to their pure green emission,excellent stability and superior carrier transport characteristics.Howe... Formamidinium lead bromide(FAPbBr_(3))nanocrystals(NCs)have been considered to be a good optoelectronic material due to their pure green emission,excellent stability and superior carrier transport characteristics.However,two-photon pumped amplified spontaneous emission(ASE)and the corresponding nonlinear optical properties of FAPbBr_(3) NCs are scarcely revealed.Herein,we synthesized colloidal FAPbBr_(3) NCs with different sizes by changing the molar ratio of FABr/PbBr_(2) in the precursor solution,using ligand assisted precipitation(LARP)technology at room temperature.Photoluminescence(PL)and time resolved photoluminescence(TRPL)spectroscopy were measured to characterize their ASE properties.And their nonlinear optical properties were studied through the Zscan technique and the two-photon excited fluorescence method.The stimulated emission properties including oneand two-photon pumped ASE have been realized from FAPbBr_(3) NCs.With large two-photon absorption coefficient(0.27 cm/GW)and high non-linear absorption cross-section(7.52×10^(5) GM),ASE with threshold as low as 9.8μJ/cm^(2) and 487μJ/cm^(2) have been obtained from colloidal FAPbBr_(3) NCs using one-and two-photon excitations.These results indicate that as a new possible green-emitting frequency-upconversion material with low thresholds,FAPbBr_(3) NCs hold great potential in the development of high-performance two-photon pump lasers. 展开更多
关键词 perovskites formamidinium lead bromide nanocrystals NONLINEAR optical gain amplified spontaneous emission
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当代大学生的社会主义信念现状的调查
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作者 赵敏 《青年探索》 1997年第5期13-14,共2页
一、调查的一般情况 为了真实反映当代大学生的社会主义信念现状,我们设计了题为“当代大学生社会主义信念状况调查”的问卷。本项调查共发问卷800份,回收792份,回收率96%。本项调查问卷大部分是由被调查对象所在院系的辅导员亲自发放... 一、调查的一般情况 为了真实反映当代大学生的社会主义信念现状,我们设计了题为“当代大学生社会主义信念状况调查”的问卷。本项调查共发问卷800份,回收792份,回收率96%。本项调查问卷大部分是由被调查对象所在院系的辅导员亲自发放,部分问卷由我亲自发放,并经由被调查对象独立填答,因而本次调查是成功的,调查结果也是真实可靠的, 展开更多
关键词 社会主义信念 当代大学生 资本主义 坚持四项基本原则 自发放 通货膨胀 国际共产主义运动 建设有中国特色的社会主义理论 调查对象 建设有中国特色社会主义理论
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新郑一中26名学生获台奖学金
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作者 刘重喜 《中州统战》 1995年第2期31-31,共1页
新郑一中26名学生获台奖学金去年11月4日下午,在新郑市一中校园内举行了首届台湾文教基金会奖学金颁奖大会,奖励今年新郑市一中毕业考取国家重点院校的李新春等26名大学生。这笔奖学金是由新郑市台胞唐碧城和刘瑞符二位先生为... 新郑一中26名学生获台奖学金去年11月4日下午,在新郑市一中校园内举行了首届台湾文教基金会奖学金颁奖大会,奖励今年新郑市一中毕业考取国家重点院校的李新春等26名大学生。这笔奖学金是由新郑市台胞唐碧城和刘瑞符二位先生为奖励家乡有志报效祖国的青年学生,向... 展开更多
关键词 名学生 新郑市 奖学 大学生 报效祖国 基金会 青年学生 自发放 再接再励 优秀学生
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建立内部监督机制 规范财政内部管理
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《浙江财税与会计》 1999年第8期38-38,共1页
近年来,我们发现在财税系统内部,分布在各业务科室的各种资金,从审批、拨款、帐务处理及其使用效果,有规章但缺乏有效制约,一定程度上存在着“灯下黑”的问题,公开性、透明度差。部分基层所通过市与乡财政体制的超收收入、市乡预算收入... 近年来,我们发现在财税系统内部,分布在各业务科室的各种资金,从审批、拨款、帐务处理及其使用效果,有规章但缺乏有效制约,一定程度上存在着“灯下黑”的问题,公开性、透明度差。部分基层所通过市与乡财政体制的超收收入、市乡预算收入级次“混库”等办法来获取收入,擅自发放奖金及补贴的问题比较突出,财政监督职能弱化。 财政监督是财政自身职能之一。加强财政监督,对提高财政管理水平,维护社会经济秩序。 展开更多
关键词 内部监督机制 财政监督 内部监督检查 财税系统 内部审计 自发放 使用效果 社会经济秩序 财政管理 帐务处理
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Numerical simulation of VIV for an elastic cylinder mounted on the spring supports with low mass-ratio
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作者 徐俊凌 朱仁庆 《Journal of Marine Science and Application》 2009年第3期237-245,共9页
With the development of the offshore deep water oil industry many researchers are focusing on the vortex-induced vibrations (VIV) of deep risers. In the present work, Reynolds-averaged Navier-Stokes (RANS) equatio... With the development of the offshore deep water oil industry many researchers are focusing on the vortex-induced vibrations (VIV) of deep risers. In the present work, Reynolds-averaged Navier-Stokes (RANS) equations were combined with the SST κ-ω turbulent model to simulate the stream-wise and transverse motion of an elastically mounted cylinder with a low mass-ratio, a natural frequency ratio of fx/fy = 1 and an Re number between 5 300 and 32 000, The four-order Runge-Kutta method was applied to solve the oscillating equation of the cylinder. The relationship between reduced velocity and parameters of the cylinder, including the lift coefficient, the drag coefficient, displacement and the vortex structure were then compared with recent experimental results and discussed in detail. The present numerical simulation reproduced effects have been observed in experiments, such as the lock-in phenomenon, the hysteretic phenomenon and beating behavior. 展开更多
关键词 VIV low mass ratio stream-wise and transverse motion TWO-DEGREE-OF-FREEDOM vortex shedding model CFD
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Pathway and policy analysis to China's deep decarbonization 被引量:1
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作者 Qiang Liu Yi Chen +3 位作者 Fei Teng Chuan Tian Xiaoqi Zheng Xuchen Zhao 《Chinese Journal of Population,Resources and Environment》 2017年第1期39-49,共11页
The Paris Agreement marks the beginning of a new era in the global response to climate change, which further clarifies the long-term goal and underlines the urgency addressing climate change. For China,promoting the d... The Paris Agreement marks the beginning of a new era in the global response to climate change, which further clarifies the long-term goal and underlines the urgency addressing climate change. For China,promoting the decoupling between economic growth and carbon emissions as soon as possible is not only the core task of achieving the medium-and long-term goals and strategies to address climate change, but also the inevitable requirement for ensuring the sustainable development of economy and society. Based on the analysis of the historical trends of the economy and social development, as well as society, energy consumption, and key end-use sectors in China, this paper studies the deep carbon emission reduction potential of carbon emission of in energy, industry, building, and transportation and other sectors with "bottom-up" modeling analysis and proposes a medium-and long-term deep decarbonization pathway based on key technologies' mitigation potentials for China. It is found that under deep decarbonization pathway, China will successfully realize the goals set in China's Intended Nationally Determined Contributions of achieving carbon emissions peak around 2030 and lowering carbon dioxide emissions per unit of gross domestic product(GDP) by 60-65% from the 2005 level.From 2030 onward, the development of nonfossil energy will further accelerates, and the share of nonfossil energies in primary energy will amounts to about 44% by 2050. Combined with the acceleration of low-carbon transformation in end-use sectors including industry, building, and transportation, the carbon dioxide emissions in 2050 will fall to the level before 2005, and the carbon dioxide emissions per unit of GDP will decreases by more than 90% from the 2005 level. To ensure the realization of the deep decarbonization pathway, this paper puts forward policy recommendations from four perspectives, including intensifying the total carbon dioxide emissions cap and strengthening the related institutional systems and regulations, improving the incentive policies for industrial lowcarbon development, enhancing the role of the market mechanism, and advocating low-carbon life and consumption patterns. 展开更多
关键词 Carbon dioxide emissions emission peak deepdecarbonization pathway policy suggestions
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Auto-Ignition and Heat Release Correlations for Controlled Auto-Ignition Combustion in Gasoline Engines
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作者 秦静 何邦全 +1 位作者 谢辉 赵华 《Transactions of Tianjin University》 EI CAS 2007年第5期328-333,共6页
Auto-ignition and heat release correlations for controlled auto-ignition(CAI)combustion were derived from extensive in-cylinder pressure data of a four-stroke gasoline engine operating in CAI combustion mode.Abundant ... Auto-ignition and heat release correlations for controlled auto-ignition(CAI)combustion were derived from extensive in-cylinder pressure data of a four-stroke gasoline engine operating in CAI combustion mode.Abundant experiments were carried out under a wide range of air/fuel ratio,speed and residual gas fraction to ensure that the combustion correlations can be used in the entire CAI engine operation range.Furthermore,a more accurate method to compute the residual gas fraction was proposed by calculating the working fluid temperature at the exhaust valve close timing in the experiments.The heat release correlation was described in two parts,one is for the first slower heat release process at low temperature,and the other is for the second faster heat release process at high temperature.Finally the heat release correlation was evaluated on the single cylinder gasoline engine running with CAI combustion by comparing the experimental data with the 1-D engine simulation results obtained with the aid of the GT-Power simulation program.The results show that the predicted loads and ignition timings match closely with the measurements. 展开更多
关键词 controlled auto-ignition (CAI) AUTO-IGNITION heat release correlation four-stroke gasoline engine
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The studies on neurogenesis induced by brain injury inadult ring dove
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作者 ZUO MING XUE(Biology Department, Beijing NOrmal University, Beijing100875, China) 《Cell Research》 SCIE CAS CSCD 1998年第2期151-158,共8页
It was the first time demonstrated by us that the number of newborn neurons was increajsed after making lesion in forebraill of adult ring dove (Streptopelia risoria)by means of autoradiography and immunohistochemistr... It was the first time demonstrated by us that the number of newborn neurons was increajsed after making lesion in forebraill of adult ring dove (Streptopelia risoria)by means of autoradiography and immunohistochemistry.Neurogenesis in the adult avian is restricted to the telencephalon. In doves with bilateral electrolytic lesion of nucleus ectostriatum (E), the mean number of proliferating cells in the lateral ventricular zone (LVZ) and newborn neurons in the forebrain increased by 1.95 times and 2.38times respectively as compared with that in intact doves. The most relllarkable increase of neurogenesis induced by nucleus ectostriatum lesions was found at the anteriorposterior level 3 (L3), where the lesion site was located.These results showed that the electrolytic brain lesion altered the distribution pattern of proliferating cells in theLVZ and resulted in increase of the number of newborn neurons in the non-VZ areas of forebrain. The changes in number and distribution pattern of proliferating cells in LVZ and newborn neurons in forebrain may be dependent on site of lesion. Studies on the relationship between proliferating cells in LVZ and newly generated neurons in non-VZ areas may help to understand the mechanism of brain plasticity and development. 展开更多
关键词 AUTORADIOGRAPHY NEUROGENESIS brain lesion ring dove
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A half-century of radioisotope neutron sources in China
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作者 Cai Shanyu 《Engineering Sciences》 EI 2009年第4期22-34,共13页
Near 50 years history of the development of radioisotope neutron sources in China is briefly reviewed.The structure design,preparing technology and production status of routine neutron sources including 210Po-Be sourc... Near 50 years history of the development of radioisotope neutron sources in China is briefly reviewed.The structure design,preparing technology and production status of routine neutron sources including 210Po-Be sources,210Po mock fission sources,241Am-Be sources,238Pu-Be sources,252Cf spontaneous fission sources and other special-shape neutron sources are summarized.In addition,the prospects of development on radioisotope neutron source in China are predicted from the needs of nuclear power construction,oil well-logging,neutron moisture gauge and neutron brachytherapy. 展开更多
关键词 radioisotope neutron source α n source spontaneous fission source source core preparing source capsule sealing quality control oil well-logging neutron moisture gauge neutron brachytherapy
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Metabolic imaging for guidance of curative treatment of isolated pelvic implantation metastasis after resection of spontaneously ruptured hepatocellular carcinoma: A case report
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作者 Bing Hao Wei Guo +5 位作者 Na-Na Luo Hao Fu Hao-Jun Chen Long Zhao Hua Wu Long Sun 《World Journal of Gastroenterology》 SCIE CAS 2016年第41期9242-9246,共5页
Spontaneous rupture of hepatocellular carcinoma(HCC) is a life-threatening complication and its prognosis is significantly poor because of the high recurrence rate after initial hepatectomy. Resection of isolated extr... Spontaneous rupture of hepatocellular carcinoma(HCC) is a life-threatening complication and its prognosis is significantly poor because of the high recurrence rate after initial hepatectomy. Resection of isolated extrahepatic metastasis of HCC has been advocated to obtain a possibility of long-term survival. However, it is a challenge for clinicians to detect implantation metastasis of spontaneously ruptured HCC. Accurate re-staging plays the most important role in making a decision on isolated metastasis resection. 18F-fluorodeoxyglucose(18F-FDG) positron emission tomography/computed tomography(PET/CT) is useful in detecting intraabdominal implantation metastasis from a variety of malignancies and shows superior accuracy to conventional imaging modalities in determining the location of metastasis. We present one patient with a new isolated pelvic implantation metastasis detected by 18F-FDG PET/CT and pathologically confirmed by PET/CT-guided percutaneous biopsy, who had a history of resection of spontaneously ruptured HCC two years ago. The patient's condition was stable at the 6-mo follow-up after resection of the isolated pelvic metastasis. 展开更多
关键词 FLUORODEOXYGLUCOSE Positron emission tomography/computed tomography Spontaneously ruptured hepatocellular carcinoma Isolated pelvic implant metastasis Re-staging Surgical resection
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Improving Open Spaces for a Sustainable City
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作者 Karin Schwabe Meneguetti Renato Leao Rego 《Journal of Civil Engineering and Architecture》 2013年第9期1150-1156,共7页
The feasibility of city living with nature as a way to restore the balance between human uses and natural processes is the focus of this paper about the city of Maringa in Southern Brazil. This urban form, a planned n... The feasibility of city living with nature as a way to restore the balance between human uses and natural processes is the focus of this paper about the city of Maringa in Southern Brazil. This urban form, a planned new town founded in 1947 upon a previous, comprehensive British land-development scheme, originally offered a friendly interaction between urban settlement and nature. Hence, this paper outlines how open spaces can be enhanced as an ecological structure, bringing parks, squares, gardens and urban farming into a productive system, both for nature's and for people's sakes. Following a morphological study, the proposed ecological structure will maintain ecological processes within the urban grid and help to preserve historical and social values, by linking a wide variety of natural and restored ecosystems and landscape features. The adoption of this kind of ecological planning will certainly result in an increase of the urban landscape quality, changing actual planning paradigm and preventing the city from environmental quality decrease. 展开更多
关键词 Open spaces TOWNSCAPE garden city ecological structure morphological studies.
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Sexual dimorphism of the electrophysiological properties of the projection neurons in the robust nucleus of the arcopallium in adult zebra finches
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作者 刘晓琳 侯国强 +1 位作者 廖素群 李东风 《Neuroscience Bulletin》 SCIE CAS CSCD 2010年第2期147-152,共6页
Objective To observe the sexual differences in electrophysiological properties of neurons in the robust nucleus of the arcopallium (RA) in adult zebra finches, and to provide the direct electrophysiological evidence... Objective To observe the sexual differences in electrophysiological properties of neurons in the robust nucleus of the arcopallium (RA) in adult zebra finches, and to provide the direct electrophysiological evidence for the sexual dimorphism of birdsong. Methods Whole-cell recording was used to record the spontaneous action potential firing rates from RA projection neurons in acute brain slices. Results The projection neurons of RA in male birds fired spontaneously at 10 Hz or above, while in female birds, the frequency was significantly lower, and even no firings could be detected. Conclusion There is a sexual difference in electrophysiological properties of projection neurons in RA, which may result from the difference in the levels of steroid hormones in birds. 展开更多
关键词 adult zebra finches the robust nucleus of the arcopallium spontaneous action potential firing rates electrophysiological properties sexual dimorphism
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A theoretical model of thulium-doped silica fiber's ASE in the 1900 nm waveband 被引量:2
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作者 于光义 常军 +3 位作者 王青圃 张行愚 刘泽金 黄庆捷 《Optoelectronics Letters》 EI 2010年第1期45-47,共3页
A theoretical model in the 1900 nm waveband for amplified spontaneous emission (ASE) of thulium-doped silica fiber is presented. The ASE spectral power as functions of the fiber length and the pump power is investigat... A theoretical model in the 1900 nm waveband for amplified spontaneous emission (ASE) of thulium-doped silica fiber is presented. The ASE spectral power as functions of the fiber length and the pump power is investigated by solving the rate and propagation equations. By calculation, when the concentration of thulium in fiber is 2.25×1025 m-3, the fiber core diameter is 2.6 μm, and the pump power is 200 mW at 808 nm, the optimal fiber length is 8.1 m, and the output power of ASE can reach 60 mW in the range of 1800-1950 nm with this fiber length. The optical-to-optical conversion is 30.3%. The optimal pump power also can be obtained by this model. 展开更多
关键词 Fiber lasers Optimization PUMPS SILICA THULIUM
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Performance of DRA with different pumping schemes based on coupling equation
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作者 袁建国 梁天宇 +1 位作者 何丽 何清萍 《Optoelectronics Letters》 EI 2011年第3期209-212,共4页
After the coupling equations of co-pumping,counter-pumping and bidirectional-pumping distributed Raman amplifiers(DRAs) are theoretically analyzed,the power distributions of these three DRAs are acquired with numerica... After the coupling equations of co-pumping,counter-pumping and bidirectional-pumping distributed Raman amplifiers(DRAs) are theoretically analyzed,the power distributions of these three DRAs are acquired with numerical analysis.The performance factors,such as net gain(NG),amplified spontaneous emissions(ASE) noise,double Rayleigh backscattering(DRB) noise,noise figure(NF) and optical signal noise ratio(OSNR),are discussed in depth.It can be found that the NGs of the three DRAs are almost equal.The counter-pumping scheme will induce higher ASE.And the co-pumping DRA has greater DRB noise,but its NF and OSNR are both better than the others'.Furthermore,the relations between signal power and NG,NF,OSNR are also investigated.It is shown that the NF and OSNR of the co-pumping scheme are superior to those of the other two schemes at small input signal power.The above conclusions can play a very important role in guiding the optimum design of DRA. 展开更多
关键词 Amplifiers (electronic) Light amplifiers Numerical analysis Optical signal processing
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Factors affecting cerebrospinal fluid opening pressure in patients with spontaneous intracranial hypotension 被引量:2
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作者 Ling-ling YAO Xing-yue HU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2017年第7期577-585,共9页
Objective: Spontaneous intracranial hypotension (SIH) is recognized far more commonly than ever before. Though usually characterized by low cerebrospinal fluid (CSF) pressure, some patients with SIH are observed ... Objective: Spontaneous intracranial hypotension (SIH) is recognized far more commonly than ever before. Though usually characterized by low cerebrospinal fluid (CSF) pressure, some patients with SIH are observed to have normal pressure values. In this study, we aimed to confirm the proportion of patients with normal CSF opening pressure (CSF OP) and explore the factors affecting CSF OP in SIH patients. Methods: We retrospectively reviewed 206 consecutive SIH patients and analyzed their clinical and imaging variables (including demographic data, body mass index (BMI), duration of symptoms, and brain imaging findings). Univariate and multiVariate analyses were performed to identify the potential factors affecting CSF OP. Results: In a total of 114 (55.3%) cases the CSF OP was 〈60 mmH2O (1 mmH2O=9.80665 Pa), in 90 (43.7%) cases it was between 60 and 200 mmH2O, and in 2 (1.0%) cases it was 〉200 mmH2O. Univadate analysis showed that the duration of symptoms (P〈0.001), BMI (P〈0.001), and age (P=0.024) were positively correlated with CSF OP. However, multivariate analysis suggested that only the duration of symptoms (P〈0.001) and BMI (P〈0.001) were strongly correlated with CSF OP. A relatively high R2 of 0.681 was obtained for the multivariate model. Conclusions: Our study indicated that in patients without a low CSF OP, a diagnosis of SIH should not be excluded. BMI and the duration of symptoms can influence CSF OP in SIH patients, and other potential factors need further investigation. 展开更多
关键词 Spontaneous intracranial hypotension Low cerebrospinal fluid opening pressure Body mass index Magnetic resonance imaging
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Optical transient waveform monitoring based on cross-gain modulation in semiconductor optical amplifier
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作者 杨义 肖中银 +1 位作者 刘建胜 王冠军 《Optoelectronics Letters》 EI 2012年第1期40-42,共3页
An all-optical transient waveform equivalent time sampling system based on cross-gain modulation (XGM) in semiconductor optical amplifier (SOA) is presented. Anoisy SOA dynamic model and PIN equyalent circuit func... An all-optical transient waveform equivalent time sampling system based on cross-gain modulation (XGM) in semiconductor optical amplifier (SOA) is presented. Anoisy SOA dynamic model and PIN equyalent circuit function are employed for system evaluating. The results show this SOA-XGM sampler with subtracting postprocessing can achieve picosecond sampling window. The shape of sampling window can be adjusted by SOA bias current and amplitude of control pulse. Compared with amplified spontaneous emission (ASE) noise of SOA and thermal noise in PIN, the jitter of sampling control pulse causes most sampling error. Simulations show that this SOA-XGM sampler can be a capable candidate for transient waveform sampling. 展开更多
关键词 Magnetic materials Optoelectronic devices
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