ICP-AES同时测定海沙中TiO2、CaO和MgO

用电感耦合等离子体发射光谱法(ICP-AES)同时测定新西兰海沙中的TiO2、CaO和MgO,确立了仪器的最佳分析条件.建立了一种可同时测定新西兰海沙中的TiO2、CaO和MgO的分析方法,该方法简单、快速、灵敏度高,结果可靠.     

Potential of using uric acid fluorescence in eye fluid for freshness assessment on Red Sea bream (Pagrus major)

Abstract

Fluorescence characteristics of uric acid in Red Sea bream (Pagrus major) eye fluid was explored as a potential rapid and simple assessment for fish freshness. To investigate this, eye fluid samples were collected during storage at 22?±?2?°C for standard uric acid measurements by high-performance liquid chromatography at 12?h intervals up until 36?h storage. Simultaneously, uric acid fluorescence spectroscopy measurements by fluorophotometer at 3?h intervals up until 36?h storage were made. High-performance liquid chromatography results showed the concentration of uric acid increased with storage time in the Red Sea bream eye fluid; changes similar to those observed in Japanese dace eye fluid, only differing in concentration and rate of accumulation. The fluorescence signals of uric acid in Red Sea bream eye fluid increased with storage time, which the high-performance liquid chromatography results confirmed. To further explore this, uric acid fluorescence signals were plotted against a standard fish freshness indicator “K value”, which is calculated from the concentration of adenosine triphosphate and its breakdown products using paper electrophoresis method. A good exponential relationship between these two parameters (determination coefficient of 0.94). A high linear correlation between the predicted K value from the uric acid fluorescence signals and the measured K value (determination coefficient of 0.94 and root mean square error of prediction of 6.37%) indicate uric acid fluorescence characteristics in fish eye fluid has a high potential to be employed as a new, fast and simple method to assess fish freshness.     

基于Sentinel-3 OLCI影像的渤海透明度遥感反演研究

透明度是海洋生态环境监测的关键指标,在军事、航海、渔业等领域均发挥着重要作用。与传统的海洋监测技术相比,遥感技术具有长时序、大范围、近实时获取海洋信息的优势,利用水色卫星观测我国海域透明度的变化,对合理开发和利用我国海洋资源有着重要的意义。利用实测透明度数据与Sentinel-3 OLCI传感器中心波段的等效遥感反射率数据构建了渤海透明度反演模型,主要包括单波段法、波段比值法和混合波段法。利用与卫星时空同步的现场透明度数据进行了模型精度验证,最终确定以B6(560 nm)与B7(620 nm)为敏感因子的混合波段模型透明度反演效果最佳,该模型透明度的反演值与实测值间决定系数(R2)为0.68,平均相对误差(MRE)为15.93%,均方根误差(RMSE)为0.48 m。在此基础上结合Sentinel-3 OLCI时间序列影像,得到2020年渤海透明度月均遥感产品,发现渤海透明度分布状况有明显的区域性与季节性特征。透明度的整体变化区间为0~10 m,其中夏季7月和8月份透明度较高,局部海域透明度可高于9 m,而冬季相对较低1月和2月份全海域不足2 m;透明度整体呈现近岸海域低、离岸海域高的空间分布特征,渤海中部、秦皇岛近岸海域透明度相对较高,渤海湾、辽东湾、莱州湾透明度常年较低。渤海透明度的分布趋势与渤海沿岸地质属性、周边河流分布情况以及沿岸城市群与工业港口的发展情况密不可分。该研究为渤海透明度遥感估算提供了可靠的理论基础,对监测渤海海洋环境具有重要的意义。     

海参胶原蛋白的提取及其基本成分的分析

提取海参中胶原蛋白并分析其基本成分.分别用碱解、酶解法提取胶原蛋白,Folin-酚试剂法测定多糖含量、蛋白含量,运用GC分析单糖成分.海参中多糖含量为14.35％,蛋白含量为0.989％.多糖的成分包括岩藻糖、甘露糖、半乳糖、葡萄糖,其中岩藻糖为主要单糖成分.本法简单,操作方便,实验灵敏,多糖得率高.