紫外分光光度法测定硫酸链霉素的含量

采用紫外分光光度法测定硫酸链霉素的含量,检测波长323 nm.硫酸链霉素在12～48 mg/L的浓度范围内,其紫外吸收值与浓度呈线性关系,回归方程为A=0.012 1 C 0.000 5,r=0.999 9;平均回收率为99.82%,RSD为0.62%.     

用紫外分光光度法测定氟甲喹含量

作者应用ＮａＯＨ（０．１ｍｏｌ／Ｌ）为溶液溶解氟甲喹可溶性粉,并以紫外分光光度法测定其含量,结果与容量法无显著性差异。     

盐酸林可霉素—盐酸环丙沙星复方制剂含量测定方法研究

用高效液相色谱法及紫外分光光度法分别测定盐酸林可霉素、盐酸环丙沙星的含量,结果表明,线性关系良好,回收率满意,适用于该产品的含量测定。     

紫外分光光度法测定扑草净粉的含量

采用紫外分光光度法测定扑草净粉中扑草净的含量,以221 nm为测定波长.方法的线性范围为0.4～8.0 μg/mL,相关系数r为0.990 6,回收率为99.28%,相对标准偏差RSD为0.47%.本方法简便快捷,具有良好的准确度和精密度,可用于扑草净粉的质量监控.     

共轭亚油酸紫外检测方法的研究

采用紫外分光光度法对乳酸菌脱脂奶发酵液中的共轭亚油酸（CLA）进行定量分析,建立共轭亚油酸紫外标准曲线,并采用气相色谱（GC法）分析法进行验证.     

微波辅助提取-紫外分光光度法测定柚皮中总黄酮含量

通过均匀设计试验考察及优化了微波辅助提取-紫外分光光度法提取柚皮黄酮的最适提取条件:微波辐射功率638W,辐射时间6min,乙醇浓度70%,固液比1:4。研究了紫外分光光度法测定柚皮中总黄酮含量的方法,以芦丁为参照品,测定波长为258nm,吸光度与芦丁浓度的线性范围在1.0～30цg/ml,相关系数R=0.9995,平均回收率为99.60%,相对标准偏差为1.0%。该方法简单、快速、准确,样品提取后不经分离可直接测定黄酮含量,是一种较理想的测定方法。     

双波长紫外分光光度法测定酒石酸泰乐菌素-盐酸多西环素可溶性粉的含量

建立了双波长紫外分光光度法同时测定酒石酸泰乐菌素-盐酸多西环素可溶性粉中酒石酸泰乐菌素和盐酸多西环素含量的检测方法。结果显示，吸收度与浓度呈良好线性关系。酒石酸泰乐菌素的平均回收率为99．90％，RSD为0．42％n=5）；盐酸多西环素的平均回收率为100．07％，RSD为0．74％（n=5）。     

Absorbance Spectra of Inter-Species Hemoglobins in the Visible and Near Infrared Regions

This study was initiated to determine if the absorbance spectra of hemoglobins from nonhuman species were sufficiently different from those of human hemoglobin to affect the applicability of pulse oximetry to common domestic species. Hemoglobin was isolated from the blood of humans, dogs, cats, horses, cows, and pigs. The millimolar extinction coefficients for oxygenated and deoxygenated hemoglobin samples were determined over the wavelength range of 600 to 1000 nm. Minor differences in the absorbance of both oxyhemoglobin and deoxyhemoglobin were found between human hemoglobin and that of the dog, cat, horse, cow, and pig. However, correction for the presence of methemoglobin, the effects of light scattering by impurities in the solution, and technical error rendered these differences statistically insignificant. The results of this study suggest that the spectral properties of canine, feline, equine, bovine, and porcine hemoglobin do not differ significantly from that of human hemoglobin and should not be a limiting factor in the application of pulse oximeters that are based on human algorithms to animal species.     

Biochar impact on the estimation of the colorimetric‐based enzymatic assays of soil

This study was carried out in order to assess the influence of biochar applications on the estimation of colorimetric‐based enzymatic assays and to verify the effectiveness of the most common methods. Since most methods used to determine enzymatic activities in the soil are based on colorimetry, biochar may absorb substrates and/or coloured products thereby distorting the analytical result. Biochar was added to two soils, with different textures and cation exchangeable capacities, at a rate of 2% (w/w), and seven enzyme activities were determined following standard methods. The biochar amendment lowered the spectrophotometer reading of the activity of FDAase and dehydrogenase in the sandy soil. In the three enzymatic activities based on p‐nitrophenol production (β‐glucosidase, phosphatase and arylsulphatase), the addition of biochar did not change the enzyme assays. The biochar led to an overestimation in terms of the protease and urease activities in the sandy soil. In the clay loamy soil, biochar did not change the response of any of the enzyme activities tested. A biochar dose of up to 2% only guarantees the effectiveness of the most common spectrophotometric methods for not excessively sandy soils.     

紫外分光光度法检测肉制品中盐酸克伦特罗残留量

目的建立一种快速检测肉制品中盐酸克伦特罗残留量的方法。方法 -环糊精与盐酸克伦特罗结合后用紫外分光光度法测定吸光度值并建立标准曲线,检测样品中盐酸克伦特罗含量。结果吸光度值强度与盐酸克伦特罗浓度在358 nm波长处呈线性关系。当包合体系p H 7.0、温度30℃、静置30 min时,检出限为0.015 mg/L,线性范围为0.05~0.15 mg/L,线性相关系数r=0.9995,精密度为2.20%~6.04%,回收率为95.0%~106.0%。结论紫外分光光度法是检测肉制品中盐酸克伦特罗残留量的简单、快速、可靠方法。