Investigation of the energy resolution with a RETGEM detector

A novel Micro-pattern gaseous detector （MPGD）, thick GEM with electrodes made of a resistive material （RETGEM） is presented. In this paper we mainly investigate the energy resolution of a RETGEM in Ar＋CO2 with different gas mixtures. The results indicate that an energy resolution 30% in single and double mode can be obtained. The existence of an optimum energy resolution is discussed.     

间歇搅拌釜中甲醇与二氧化碳合成碳酸二甲酯

二氧化碳与甲醇直接合成碳酸二甲酯是一条对化学工业和环境保护都具有吸收力的工艺路线。本文在间歇式反应器中筛选出镁粉作催化剂,测试了各种反应条件的影响,得出了适合的反应条件。     

再谈“负温状态的稳定性”——答王家庆同志

重申了关于负温状态稳定性的观点，认为关于负温状态稳定性的讨论是必要的，稳定性条件的推导是合理的。     

利用啁啾光纤光栅色散特性实现波长可调谐的主动锁模掺铒光纤环行腔激光器

在环形腔主动锁模光纤激光器中引入啁啾光纤光栅，利用啁啾光纤光栅的大色散特性，通过调节调制频率，实现波长调谐，调谐范围2nm。所得脉冲为重复频率2．5GHz，脉宽约60ps的正啁啾脉冲，。     

A Dual-Wavelength Cladding-Pumped Er^3＋/Yb^3＋ Codoped Fibre Laser System with More Than 2 W Output and Tunable Wavelength Spacing

A dual-wavelength laser system with wideband tunable wavelength spacing and more than 2 W output power is proposed and demonstrated. The operation principle of the laser system is based on the saturation gain characteristic of a cladding-pumped Era＋ /yba＋ co-doped fibre amplifier combining with a wideband tunable fibre laser with fiat power spectrum. The tuning range of the wavelength spacing is continuous within a 35 nm spectral range, and the power difference between both lasing wavelengths can be easily adjusted and controlled by a variable optical attenuator. The total output power can approximately keep unchangeable when the wavelength spacing and the power difference between both lasing wavelengths are continuously tuned and changed. The maximum total output power of the laser system is about 2.22 W.     

三阶拟线性全双曲方程及其上下解序列

本文运用微分不等式定理,定义了三阶拟线性全双曲方程特征问题的上下解,构造了收敛于特征问题解的一对上、下解单调序列,提供了寻求近似解的一种可行方法。     

一维Coulomb势

研究了Ｓｃｈｒｏｅｄｉｎｇｅｒ方程在一维ｏｕｌｏｍｂ势ｂ│ｘ│下的精确解，得到决定能级的超越方程及波函数，并给出了大量子数下能级的具体表式。     

若干二维问题的WKB近似能级

讨论了二维空间的WKB近似方法，导出了Bohr-Sommerfeld量子化条件，并计算了若干具体问题的能级，包括中心势情况和Aharonov-Bohm势加中心势情况。