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121.
建立高效液相色谱-串联质谱(LC-MS/MS)测定动物血浆中罗匹尼罗浓度的方法。血浆经乙酸乙酯萃取后,以HPLC分离,电喷雾离子化(ESI~+)串联质谱检测。以甲醇-乙腈-0.1‰冰醋酸(36:9:55)为流动相,流速为0.2mL·min~(-1),采用Ultimate XB-C 18柱(150mm×2.1mm,3μm)分离,在三级四极杆串联质谱中经电喷雾电离源(ESI)离子化,以多反应监测(MRM)方式进行检测。盐酸罗匹尼罗、盐酸苯海拉明(内标)的扫描离子对m/Z分别为261→114和m/Z 256→167。LC-MS/MS测定血浆中罗匹尼罗线性范围为0.02—400ng·mL~(-1),范围内线性关系良好(r=0.9998);以3个浓度水平的质量控制样品求得各浓度水平日内、日间精密度(RSD)均小于15.2%。在非临床药代动力学研究中,应用此法测定了受试兔子血浆中罗匹尼罗的浓度。该法灵敏、快速、准确,操作简便,样品处理方便,线性范围宽,该方法检测快速、专一、灵敏,可满足罗匹尼罗临床前药代动力学研究和临床药动学研究的要求。 相似文献
122.
We propose schemes to generate an n-coherent-pulse GHZ state and a cluster state via the interaction between n coherent pulses and a two-sided cavity.In these schemes,a strong coupling condition is not needed,which makes the protocols possibly able to be implemented based on the current experiment technology. 相似文献
123.
124.
The conversion of the frequency modulated pulse induced from frequency modulation (FM) to amplitude modulation (AM) by the polarization mode dispersion (PMD) is theoretically and experimentally investigated. When there is no polarizer at the output end of a fiber system, the amplitude modulation depth is stable by 8%. Random amplitude modulation is observed when a polarizer is placed at the output end of the fiber system. The observed minimum and maximum modulation depths in our experiment are 5% and 80%, respectively. Simulation results show that the amplitude modulation is stable by 4% induced mainly by group velocity dispersion (GVD) when there is no polarizer, and the amplitude modulation depth displays the random variation character induced by the GVD and PMD. Lastly, a new fiber system scheme is proposed and little amplitude modulation is observed at the top of the output pulse. 相似文献
125.
Gong-Yi Li Xiao-Dong Li Hao Wang Lin Liu 《Applied Physics A: Materials Science & Processing》2010,98(2):293-298
In this communication, we report on the attempt to make full use of the off-gases from polycarbosilane-derived SiC preparation,
and we successfully synthesized long SiC nanowires in large areas with Fe(NO3)3 as catalyst. The nanowires have diameters of about 80–300 nm and lengths of millimeters, and they are identified as single
crystals β-SiC along the 〈111〉 direction. The VLS mechanism was employed to interpret the nanowire growth. 相似文献
126.
We demonstrate a 1047 nm Nd:LiYF4 (Nd:YLF) laser by directly pumping into the upper lasing level with a tunable Ti:Sapphire laser. The results obtained for direct upper laser level pumping at 863, 872 and 880 nm of Nd:YLF were compared with traditional 806 nm pump band excitation. Highly efficient 1047 nm continuous-wave (CW) laser emission under direct pumping at 880 nm in an 8 mm thick, 1.0 at.% Nd:YLF crystal is obtained. The slope efficiency is improved from 55.6% for traditional pumping at 806 nm to 76.3% for direct pumping at 880 nm. 相似文献
127.
Ren J Huo CF Wen XD Cao Z Wang J Li YW Jiao H 《The journal of physical chemistry. B》2006,110(45):22563-22569
The adsorption and dissociation of thiophene on the MoP(001), gamma-Mo(2)N(100), and Ni(2)P(001) surfaces have been computed by using the density functional theory method. It is found that thiophene adsorbs dissociatively on MoP(001), while nondissociatively on gamma-Mo(2)N(100) and Ni(2)P(001). On MoP(001), the dissociation of the C-S bonds is favored both thermodynamically and kinetically, while the break of the first C-S bond on gamma-Mo(2)N(100) has an energy barrier of 1.58 eV and is endothermic by 0.73 eV. On Ni(2)P(001) there are Ni(3)P(2)- and Ni(3)P-terminated surfaces. On the Ni(3)P(2)-terminated surface, the dissociation of the C-S bonds of adsorbed thiophene is endothermic, while it is exothermic on the Ni(3)P-terminated surface. 相似文献
128.
Wei Gao Xiao-Dong Tan Ming-Feng Wang Yi-Zhuang Zheng 《International Journal of Theoretical Physics》2013,52(6):2092-2098
We propose an efficient quantum memory scheme with natural inhomogeneous broadening in an asymmetric optical cavity. The scheme uses the strong rephasing pulses like traditional photon echo techniques rather than spectral holeburning, which enables us to have the potential implementation in a much broader range of material systems. In the condition of impedance matching to an optical cavity, we find that the input light pulse can be completely absorbed by an atomic ensemble. We also show that the quantum memory efficiency can be equal to unity even for a small optical depth of the atomic system. 相似文献
129.
130.
Stable single longitudinal mode erbium-doped silica fiber laser based on an asymmetric linear three-cavity structure
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We present a stable linear-cavity single longitudinal mode (SLM) erbium-doped silica fiber laser. It consists of four fiber Bragg gratings (FBGs) directly written in a section of photosensitive erbium-doped fiber (EDF) to form an asymmetric three-cavity structure. The stable SLM operation at a wavelength of 1545.112 nm with a 3-dB bandwidth of 0.012 nm and an optical signal-to-noise ratio (OSNR) of about 60 dB is verified experimentally. Under laboratory conditions, the performance of a power fluctuation of less than 0.05 dB observed from the power meter for 6 h and a wavelength variation of less than 0.01 nm obtained from the optical spectrum analyzer (OSA) for about 1.5 h are demonstrated. The gain fiber length is no longer limited to only several centimeters for SLM operation because of the excellent mode-selecting ability of the asymmetric three-cavity structure. The proposed scheme provides a simple and cost-effective approach to realizing a stable SLM fiber laser. 相似文献