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101.
102.
A flow gas low-pressure multi-wire proportional chamber(LPMWPC)with an active area of 180 mm×80 mm has been developed for the flying time test of the recoil nuclei on super heavy nuclear experiments.The LPMWPC detector can be operated in single as well as double step operational modes.In the case of double step operational mode with a high gas amplification factor,signals fromα-particles reside well above the electronic noise.The gas leakage rate and time resolution obtained from theα239Pu source are shown and discussed at the condition of 3 mbar Isobutane gas.It was shown that the time resolution was better than 2.9 ns at the best work condition,and the detecting efciency was larger than 98%at the low energyαparticles.So the LPMWPC is fit to measure the flying time in the super heavy nuclear fragments experiment. 相似文献
103.
从Schrdinger方程出发,结合自旋的唯象描述、简单的相对论考虑和适当的猜测,写出了Dirac方程的正确形式. 相似文献
104.
从Schr(o)dinger方程出发,结合自旋的唯象描述、简单的相对论考虑和适当的猜测,写出了Dirac方程的正确形式. 相似文献
105.
A novel method for fabricating dual-wavelength fiber Bragg gratings (FBGs) by using one phase mask is developed. The method is based on a double-exposure technique. Our technique lends itself to writing gratings with controllable reflectivity and separation of two Bragg wavelengths. A grating with two equal transmission peaks of 20.25 dB is obtained by this method and the separation of the two Bragg wavelengths is about 0.8 nm. With the grating, we demonstrate a dual-wavelength erbium-doped fiber ring laser whose interval of the two peaks is 0.8 nm. The laser's peak powers can get 3.1 mW above and have a good stability. 相似文献
106.
Photon—Storage in Optical Memory Cells Based on a Semiconductor Quantum Dot—Quantum Well Hybrid Structure 下载免费PDF全文
We report a new type of photonic memory cell based on a semiconductor quantum dot (QD)--quantum well (QW) hybrid structure, in which photo-generated excitons can be decomposed into separated electrons and holes, and stored in QW and QDs respectively. Storage and retrieval of photonic signals are verified by time-resolved photoluminescence experiments. A storage time in excess of l00ms has been obtained at a temperature of 10K while the switching speed reaches the order of ten megahertz. 相似文献
107.
High-Power Er^3+/Yb^3+ Codoped Double-Cladding Fibre Amplifier with More Than 2 W Output Power 下载免费PDF全文
A high-power Er^3 /Yb^3 -codoped double-cladding all-fibre amplifier was successfully demonstrated and exper-imentally investigated. The amplifier could be operated with a maximum output power of 2.18 W and 2.11 Wat 1541nm and 1550nm wavelengths, respectively, when the maximum pump power was 6.07W. The powerconversion effciency was up to 35.6% and 34.4% at the two wavelengths, respectively. The output power and the gain were greater than 2.00 W and 20.OdB, respectively, in the wavelength range from 1539nm to 1565nmfor 20.OmW input signal power. The gain fluctuation and the noise figure around 1550nm wavelength were less than 0.3 dB and 6.0 dB, respectively. 相似文献
108.
Synthesis, MSssbauer Spectra and Magnetic Properties of Quasi-One-Dimensional Fe3O4 Nanowires 下载免费PDF全文
Quasi-one-dimensional Fe3O4 nanowires in diameter of about 200nm were assembled into anodic aluminium oxide templates via electrodepositing and heat-treating processes. The nanowires have a polycrystalline spinel structure with α=8.317А, and each nanowire is composed of fine Fe3O4 crystallites with size of about 30nm. 相似文献
109.
110.
两级解调FBG传感复用技术 总被引:2,自引:2,他引:0
采用两级解调的方法,优化了WDM/SDM光纤光栅传感复用系统的解调规则,探索了采用双解调系统,同时对光纤光栅传感阵列进行解调以提高传感系统解调速度的方法.在系统设计中采用Petri Net理论来解决多解调系统协调运行的问题.通过构建双解调四通道的布喇格光纤光栅应变传感复用系统验证了多解调复用技术的可行性,采用排队论理论,模拟仿真了双解调系统的性能.理论分析和实验表明双解调系统的平均等待时间比传统的解调方法的平均等待时间低一个数量级. 相似文献