排序方式: 共有8条查询结果,搜索用时 15 毫秒
1
1.
2.
分光光度计与计算机联机 总被引:3,自引:1,他引:3
人工记录的方法进无法准确记录分光光度计所批示的消光值,特别是因浓度(10^-5-10^-4mol/L)改变,而导致精度和准确度不高,采用计算机的方式是可以克服此种弊端,精确度和准确度都很高并有良好线性关系,且自动绘图(即经耳定律的线性图)并输出。此装置具有快速、直观、图文并茂等特点。 相似文献
3.
4.
<正>We describe a mobile molecular Doppler wind lidar(DWL) based on double-edge technique for wind measurement of altitudes ranging from 10 to 40 km.A triple Fabry-Perot etalon is employed as a frequency discriminator to determine the Doppler shift proportional to the wind velocity.The lidar operates at 355 nm with a 45-cm-aperture telescope and a matching azimuth-over-elevation scanner that provides full hemispherical pointing.To guarantee wind accuracy,a single servo loop is used to monitor the outgoing laser frequency to remove inaccuracies due to the frequency drift of the laser or the etalon.The standard deviation of the outgoing laser frequency drift is 6.18 MHz and the corresponding velocity error is 1.11 m/s.The wind profiles measured by the DWL are in good agreement with the results of the wind profile radar(WPR).Evaluation is achieved by comparing at altitudes from 2 to 8 km.The relative error of horizontal wind speed is from 0.8 to 1.8 m/s in the compared ranges.The wind accuracy is less than 6 m/s at 40 km and 3 m/s at 10 km. 相似文献
5.
本文提出了一种对原有的测定纯液体饱和蒸气压装置的改进。克服了人工记录数据的繁杂,也减少了实验者的劳动强度,并为后继的数据处理减小了误差。此装置在测量精度和数据处理自动化程度上均优于常规的测定。其操作简单、直观,实验时间也大为缩短。 相似文献
6.
Analysis of Detectors and Transmission Curve Correction of Mobile Rayleigh Doppler Wind Lidar 下载免费PDF全文
A mobile molecular Doppler wind lidar (DWL) based on double-edge technique is presented for wind measurement at altitudes from 10 km to 40 km. A triple Fabry-Perot etalon is employed as a frequency discriminator to determine the Doppler shift proportional to the wind velocity. The lidar operates at 355 nm with a 45-cm aperture telescope and a matching azimuth-over-elevation scanner that can provide full hemispherical pointing. In order to guarantee the wind accuracy, different forms of calibration function of detectors in different count rates response range would be especially valuable. The accuracy of wind velocity iteration is improved greatly because of application of the calibration function of linearity at the ultra low light intensity especially at altitudes from 10 km to 40 km. The calibration functions of nonlinearity make the transmission of edge channel 1 and edge channel 2 increase 38.9% and 27.7% at about 1 M count rates, respectively. The dynamic range of wind field measurement may also be extended because of consideration of the response function of detectors in their all possible operating range. 相似文献
7.
An aminophenol ligand, N,N,N′-tri(2-hydroxy-5-methylbenzyl)-1,2-ethanediamine, was prepared through the Mannich reaction, and structurally characterized by NMR, IR, MS and single-crystal X-ray diffraction. The title compound (C26H32N2O3, Mr = 420.54) belongs to the monoclinic system, space group P21/n with a = 8.6233(14), b = 10.2655(16), c = 26.017(4) ′, β = 95.797(2)o, V = 2291.3(6) ′3, Z = 4, the final R = 0.0461 and wR = 0.1139 for 4267 unique reflections (Rint = 0.028) with 11691 observed ones (I > 2σ(I)). 相似文献
8.
采用计算机辅助二次回归正交设计法系统地研完了Cr(Ⅲ)与2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚(5-Br-PADAP)和DEA三元配合物显色反应的最佳条件,干扰离子影响的消除方法,建立了测定Cr(Ⅱ)的新方法。其最大吸收波长为595nm,ε595=5.7×104,其检出限为0~20μg/25ml,配合物组成比为121。将该方法用于测定合成水样,结果令人满意。 相似文献
1