紫外分光光度法对几种新疆产黑加仑中维生素C含量的测定

目的:建立对黑加仑中维生素C含量的紫外分光光度法的测定方法,并依据维生素C的含量初步评价这几种产地黑加仑的质量优劣。方法:采用pH值5.2的硫酸溶液,在262nm处测定其吸收度。结果:维生素C平均回收率为99.33%,RSD1.99%。结论:所建立方法简便,准确,可靠,可作为黑加仑中维生素C含量测定的方法。其中以吉木萨尔产的含量为最高。

18-8钢在稀盐酸中的晶间腐蚀分析及对策

本文从不锈钢的耐蚀原理入手 ,重点分析了 18-8钢发生晶间腐蚀的原因及采取的预防对策。

Vision Enhancement Technology of Drivers Based on Image Fusion

The rise of urban traffic flow highlights the growing importance of traffic safety.In order to reduce the occurrence rate of traffic accidents,and improve front vision information of vehicle drivers,the method to improve visual information of the vehicle driver in low visibility conditions is put forward based on infrared and visible image fusion technique.The wavelet image confusion algorithm is adopted to decompose the image into low-frequency approximation components and high-frequency detail components.Low-frequency component contains information representing gray value differences.High-frequency component contains the detail information of the image,which is frequently represented by gray standard deviation to assess image quality.To extract feature information of low-frequency component and high-frequency component with different emphases,different fusion operators are used separately by low-frequency and high-frequency components.In the processing of low-frequency component,the fusion rule of weighted regional energy proportion is adopted to improve the brightness of the image,and the fusion rule of weighted regional proportion of standard deviation is used in all the three high-frequency components to enhance the image contrast.The experiments on image fusion of infrared and visible light demonstrate that this image fusion method can effectively improve the image brightness and contrast,and it is suitable for vision enhancement of the low-visibility images.

白芷化学成分的研究

目的研究白芷Angelica dahurica的化学成分。方法采用硅胶柱色谱、Sephadex LH-20,重结晶等手段进行分离纯化,采用波谱方法鉴定结构。结果从白芷中分离并鉴定了11个化合物,分别为β-谷甾醇(1)、cnidilin(2)、异欧前胡素(3)、欧前胡素(4)、水合氧化前胡内酯(5)、栓翅芹烯醇(6)、白当归脑(7)、花椒素(8)、neobyakan-gelicol(9)、比克白芷素(10)、水合氧化前胡素(11)。结论化合物8为首次从白芷中发现。

都梁滴丸提取物的含量测定

目的建立成品前都梁滴丸提取物的含量测定方法。方法外标法定量,Kromasil C18色谱柱(4.6 mm×250 mm,5μm),测定阿魏酸的流动相CH3CN与H2O(1 L水中含1mLH3PO4)的体积比为17∶83,检测波长316 nm;测定欧前胡素、异欧前胡素流动相CH3OH与H2O的体积比为70∶30,检测波长300 nm。结果阿魏酸进样量在0.023 4～0.140 6μg范围内,线性关系良好,r=0.999 9,平均回收率为100.4%,RSD为0.39%;欧前胡素进样量在0.016 1～0.322 0μg范围内,线性关系良好,r=0.999 9,平均回收率为102.9%,RSD为0.65%;异欧前胡素进样量在0.004 4～0.087 2μg范围内,线性关系良好,r=0.999 9,平均回收率为100.0%,RSD为0.24%。结论该方法简便、灵敏、准确,可作为都梁滴丸成品前提取物的质量控制方法。

浅谈农村中小学英语两极分化的现状、原因及对策

与城镇中小学教育条件相比,农村中小学校体现出一定的落后性.在农村初中英语教学中,学生的成绩出现两极分化现象较为严重.针对这样的教学情况,教师应该从多元化的角度分析出现这种现象的原因,并提出有效的对策.本文就农村中小学英语两极分化的现状、原因以及对策展开了一系列的探究.