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1.
左手介质椭圆光波导基模传播特性   总被引:1,自引:0,他引:1  
熊天信  杨儒贵 《光子学报》2006,35(7):1099-1102
在椭圆柱坐标系中,采用分离变量方法,得出了左手介质椭圆光波导本征方程的近似解,通过数值计算,分析了椭圆波导偏心率、左手介质的电容率、磁导率对椭圆光波导基模传播特性的影响,并将左介质光波导与右手介质光波导基模特性进行对比,得出左手介质光波导的基模特性与右手介质光波导基模特性差别不大的结论.  相似文献   
2.
20GHz注入锁模光纤激光器实验   总被引:3,自引:0,他引:3  
稳定、波长可调谐的窄脉冲光源是未来光时分复用/波分复用光纤通信系统的重要组成部分。报道了一个20GHz的注入锁模光纤激光器的实验。利用一个10GHz的导体体激光器作为光源,最终得到了波长可调谐的重复频率为20GHz、脉冲宽度为12.4ps的光脉冲,波长的调谐范围为16nm。  相似文献   
3.
8字形主被动锁模掺Er3+光纤激光器   总被引:6,自引:0,他引:6  
在理论上分析了利用非线性光学环形镜作为等效可饱和吸收体压缩脉冲进行锁模的物理机制。利用8字形主被动混合锁模的结构在调制频率2.498749GHz下,在1.543μm处获得了12ps的锁模脉冲输出,对应谱宽0.22nm,时间脉宽积0.33。在抽运功率50mW情况下,输出脉冲平均功率3.715mW。在调制频率2.499344GHz、2.499114GHz和2.498999GHz时分别并获得了2~4阶幅度较为均衡的有理数谐波锁模脉冲序列。  相似文献   
4.
Letf (m) be an irreducible quadratic polynomial with integral coefficients and positive leading coefficient. Under the assumption of Extended Riemann Hypothesis, we obtain new remainder terms in the upper bounds on primes represented byf(m) orf(p) which greatly improve Bantle's recent results. As an application, we obtain, in the second part of the paper, a new result on the lower bound of the least primes in arithmetic progressions with some difference.  相似文献   
5.
On Selecting k Balls from an N-circle Without Unit SeparationCaiTianxin(蔡天新)(DepartmentofMathcmatics,HangzhonUniversity,Hangz...  相似文献   
6.
By using the amplified 10-GHz, 5.5-ps sech2 pulses with high quality and chirp-free from regeneratively mode-locked fiber laser (RMLFL) as the soliton source, 2-5 order optical soliton phenomena are observed successfully in a 4.28-km dispersion flattened fiber. The experimental results agree well with the theoretical calculation.  相似文献   
7.
Focused on the low noise figure requirements of erbium-doped preamplifiers, a two stage cascade preamplifier was presented based on the optimized design. With the total fiber length of 31.4 m and total pump power of 135 mW, this preamplifier can produce above 30-dB gain and keep the noise figure below 4.76dB for all C-band signals, with the minimum noise figure as low as 3.38 dB for -30-dBm, 1550-nm signal.  相似文献   
8.
Herein we report a fluorescent method for sensitive and selective detection of uranyl ions using CdTe quantum dots functionalized with mercaptopropionic acid, which the fluorescence of the quantum dots could be quantitatively quenched through electron transfer mechanism. The detection limit of the method was estimated to be 4 nM, less than the maximum allowed content of 130 nM for uranyl in drinking water defined by the U.S. Environmental Protection Agency. Furthermore, the probe was successfully applied in detection of uranyl ions in real samples, demonstrating its potential practical applications for monitoring of uranyl ions in environment.  相似文献   
9.
李映晖  杨天行 《计算物理》1998,15(6):717-725
主要研究求解Biot固结方程组的广义差分法及其数值实验,得到了计算结果。  相似文献   
10.
Molecularly imprinted polymer(MIP) films for hemoglobin detection were prepared onto the Au/Cr coated surface plasmon resonance(SPR) sensor chips by the in situ electropolymerization of 3-aminophenylboronic acid(3-APBA).The formation of the films and rebinding processes of hemoglobin were monitored by in situ electrochemical-SPR(EC-SPR) spectroscopy,with allowed real-time observation of the simultaneous changes in electrochemical and optical properties of the films.Scanning electron microscopy(SEM) and atomic force microscopy(AFM)were used to characterize the surface morphologies of the MIP films.The effects of pH,ion strength,different metal ions on rebinding Hb,the specific binding and the selective recognition were investigated.The results obtained with the molecular imprinted SPR chips indicate a good adsorption of Hb in a range of 0.0005-5 mg/mL in 0.05 mol/L sodium phosphate buffer at pH=7.0.A linear calibration curve(R2=0.94) of the SPR sensor for Hb detection was obtained in a range of 0.05-5 mg/mL.The detection limit for hemoglobin by this method was 0.000435 mg/mL(S/N=3).Interference studies indicate that the MIP films have a good selectivity compared with the referenced proteins.The stability of the sensor was also established.Results indicate that the SPR sensor chip keeps 87.6% of its original response after 14 d of storage under dry and ambient conditions.  相似文献   
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