利用WDM光纤耦合器的光纤光栅传感解调技术

根据WDM光纤耦合器波长解调方案的工作原理、偏振特性以及影响系统波长分辨力的因素,提出一种改进的利用WDM光纤耦合器的光纤光栅传感解调技术.该技术在原技术的基础上,采用偏振控制器控制入射光偏振状态,提高了解调的精度和稳定性.对WDM光纤耦合器的多次波长扫描结果表明,采用偏振控制器后,其波长误差可减小到5pm左右.实验采用1540/1560nm的WDM光纤耦合器对单点光纤光栅应变传感器进行静态解调,结果表明:按此技术开发的解调系统具有0.01nm波长分辨力和10nm的波长线性解调范围.

Linear and nonlinear optical properties of the PbSe quantum dots doped germane-silica glass optical fiber

We report development of a new fiber doped with PbSe quantum dots for nonlinear optical applications. PbSe quantum dots related absorption peaks were obtained at 1021, 1093 and 1351 nm. The resonant optical nonlinearity and attenuation at 1500 nm were measured to be 9.4 × 10−16 m2/W and 0.01 dB/m, respectively. The emission around 1540 nm was observed upon near resonant pumping at 1064 nm.

粘红酵母对铀的吸附研究

Characteristic of uranium biosorption in water solution by Rhodotorula glutinis was investigated in the present study and the optimal pH for uranium adsorption was found to be 6-7.At the same time,maximum adsorption capacity of 149.4 mgU/(g dry cell)was identified,and Langmuir adsorption models can be used to simulate the isothermal biosorption process with high correlation coefficient of 0.99.According to Fourier transform infrared spectra,a new peak at wave number of 904 cm-1,which can be assigned to the ...中文摘要：研究了粘红酵母对水溶液中铀的吸附行为,发现其吸附铀的最佳pH值为6～7,最大吸附量为149.4mgU.g-1,其吸附等温线和Langmuir吸附等温方程符合较好,相关系数R2达到0.99;比较吸附铀前后粘红酵母的红外光谱图发现,吸附过铀的菌体的红外光谱在904cm-1处出现了一个新的峰,此峰为UO2的伸缩振动峰,说明粘红酵母确实对铀发生了吸附作用。此外,氨基或羟基的伸缩振动峰由3309移至3287cm-1,细胞壁中碳水化合物或醇中C—O键伸缩振动发生位移,由1068移至1080cm-1,说明这些基团可能参与了吸附过程;蛋白质的特征吸收峰(1653,1540,1237cm-1)在吸附前后基本无明显变化,表明粘红酵母的主要成分及结构仍保持完整。吸附后的菌体利用0.1mol.L-1的NaHCO3处理后可解吸出其中96%的铀,可见该菌在铀矿废水处理方面具有广阔的应用前景。

粘红酵母对铀的吸附研究

研究了粘红酵母对水溶液中铀的吸附行为,发现其吸附铀的最佳pH值为6～7,最大吸附量为149.4mgU.g-1,其吸附等温线和Langmuir吸附等温方程符合较好,相关系数R2达到0.99;比较吸附铀前后粘红酵母的红外光谱图发现,吸附过铀的菌体的红外光谱在904cm-1处出现了一个新的峰,此峰为UO2的伸缩振动峰,说明粘红酵母确实对铀发生了吸附作用。此外,氨基或羟基的伸缩振动峰由3309移至3287cm-1,细胞壁中碳水化合物或醇中C—O键伸缩振动发生位移,由1068移至1080cm-1,说明这些基团可能参与了吸附过程;蛋白质的特征吸收峰(1653,1540,1237cm-1)在吸附前后基本无明显变化,表明粘红酵母的主要成分及结构仍保持完整。吸附后的菌体利用0.1mol.L-1的NaHCO3处理后可解吸出其中96%的铀,可见该菌在铀矿废水处理方面具有广阔的应用前景。

从CsCl靶中分离I、Ba和Ce的化学流程

用47MeV/nucleon的12C离子轰击133Cs靶,产生许多种不同元素的同位素。利用经典的化学分离方法,从大量的Cs和其它反应产物混合物中分离出I、Ba和Ce等。使用离线γ谱学方法,完成I、Ba、Ce等样品的γ活性测量。根据每种元素不同同位素的特征γ射线峰的强度和丰度,对I、Ba和Ce等样品中杂质的含量进行分析。结果显示该流程对杂质元素去污的效果是满意的。

Observation of pi(+)pi(-)pi(+)pi(-) photoproduction in ultraperipheral heavy-ion collisions at root s(NN)=200 GeV at the STAR detector

We present a measurement of pi(+)pi(-)pi(+)pi(-) photonuclear production in ultraperipheral Au-Au collisions at root s(NN) = 200 GeV from the STAR experiment. The pi(+)pi(-)pi(+)pi(-) final states are observed at low transverse momentum and are accompanied by mutual nuclear excitation of the beam particles. The strong enhancement of the production cross section at low transverse momentum is consistent with coherent photoproduction. The pi(+)pi(-)pi(+)pi(-) invariant mass spectrum of the coherent events exhibits a broad peak around 1540 +/- 40 MeV/c(2) with a width of 570 +/- 60 MeV/c(2), in agreement with the photoproduction data for the rho(0)(1700). We do not observe a corresponding peak in the pi(+)pi(-) final state and measure an upper limit for the ratio of the branching fractions of the rho(0)(1700) to pi(+)pi(-) and pi(+)pi(-)pi(+)pi(-) of 2.5% at 90% confidence level. The ratio of rho(0)(1700) and rho(0)(770) coherent production cross sections is measured to be 13.4 +/- 0.8(stat.) +/- 4.4(syst.)%.