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1.
甘氨酸、谷氨酸、缬氨酸和苯丙氨酸与硫酸铜发生灵敏的显色反应,形成蓝色配合物,由于最大吸收波长接近,吸收光谱重叠,用传统的光度法难以进行单一组分的测定。本文通过测定甘氨酸、谷氨酸、缬氨酸和苯丙氨酸模拟混合试样在660nm~750 nm波长范围的吸收光谱,采用偏最小二乘法建立校正模型,对其含量进行预测,结合光度法建立同时测定以上氨基酸含量的新方法,方法应用于牛奶样品中甘氨酸、谷氨酸、缬氨酸和苯丙氨酸含量的同时测定。对模拟混合试样,回收率98.46%~98.79%:RPEs为1.67%~2.34%。  相似文献   

2.
创立了复方甲硝唑注射液中氯霉素和甲硝唑的衍生光谱快速测定法。用计算机Excel绘制氯霉素和甲硝唑的衍生光谱,选择其峰点236.0 nm和交点223.0 nm为测定波长,可排除两组分的互相干扰,直接测定复方甲硝唑注射液中两组分的含量。氯霉素的比耳线性范围为(9.890~32.13)μg/mL,r=0.9995;甲硝唑为(10.09~30.28)μg/mL,r=0.9992。氯霉素和甲硝唑的平均回收率和相对标准偏差分别100.4%,1.3%和100.8%,0.68%。新方法简便、快速、准确,适用于医院制剂复方甲硝唑注射液的质量检测。  相似文献   

3.
混合物光谱中组分数的确定是分析化学中常要遇到的问题。因子分析方法是对一组混合物样品的数据矩阵进行特征值分析,从而确定组分数。这种方法在实际应用时有很大的局限性,例如对一个待测的多组分未知样品是无法配制一系列含有同样组分而又有不同的相对浓度,个数掇于组分数的样品。三维荧光光谱是随激发,发射波长同时变化的荧光光谱。对应于每一对激发,发射波长的各个相对荧光强度,构成了荧光的激发—发射矩阵(EEM)。它的不同行对应于不同的荧光激发波长,不同列对应不同的发射波长。一个荧光试样就可以有一个EEM。  相似文献   

4.
偏最小二乘法同时测定食醋的有效成分和防腐剂的含量   总被引:3,自引:1,他引:2  
偏最小二乘方法建立近红外光谱与组分浓度的多元校正模型,用于同时快速测定食醋的有效成分(总酸)和防腐剂(苯甲酸)含量。采用透射模式,样品不经任何处理测定近红外光谱。用17个食醋样品建立偏最小二乘法(PLS)模型,用3个样品作为预测样品以评估PLS模型。结果:食醋中的总酸和苯甲酸在2 125~2 325 nm区域之间,与光谱有良好的线性关系,总酸的PLS模型中,隐变量为3时,预测均方根误差0.038 7 g·L~(-1),总酸含量与光谱的线性相关系数达到0.999 7,相对预测误差5.89%;苯甲酸的PLS模型中,隐变量为6时,预测均方根误差降至0.013 8 g·L~(-1),苯甲酸含量与光谱的线性相关系数达到0.999 8,相对预测误差降至4.29%。  相似文献   

5.
鼻炎滴剂是中西复方制剂,主要成分有黄芩苷、盐酸麻黄碱、金银花、辛夷油、冰片等.本文研究建立了数学分离-多波长直线回归法,用于测定鼻炎滴剂中黄芩苷和盐酸麻黄碱的含量.黄芩苷和盐酸麻黄碱的最大吸收波长分别为278.0 nm和257.0 nm,将2组分吸收强度较大的242.0 nm~283.0 nm选为测定范围.在测定范围内选择42个点进行测定,使用数学分离-多波长直线回归方法计算分析,直接测定了鼻炎滴剂中的黄芩苷和盐酸麻黄碱含量.本文研究使用的市售鼻炎滴剂中2种药效成分的平均回收率和相对标准偏差分别为102.0%,0.86%和98.2%,0.87%.数学分离-多波长直线回归法简单、快速、准确、适用于鼻炎滴剂的质量控制过程.  相似文献   

6.
遗传神经网络用于药物液相色谱分离条件的优化   总被引:7,自引:5,他引:2  
目的:遗传神经网络用于药物液相色谱分离条件的优化。方法:使用均匀设计法同时考察了离子对试剂浓度、缓冲液浓度和甲醇的体积百分比等液相色谱分离条件对去痛片模拟样品中4种组分分离的影响,采用遗传神经网络方法建立了有效的分离条件预测模型。结果:对遗传神经网络模型所预测的最佳分离条件进行实验,获得了比较满意的分离结果。结论:遗传神经网络可有效地用于药物液相色谱分离条件的优化。  相似文献   

7.
研究建立计算机程序一多波长直线回归法,以测定药品牙周康胶囊中甲硝唑和芬布芬的含量.在277.0 nm~318.0 nm波长范围内,选择42个波长点进行测定;采用计算机多波长直线回归程序计算;不经分离,直接测定牙周康胶囊中甲硝唑和芬布芬的含量.两者的平均回收率和相对标准偏差,分别为98.3%,0.75%和98.9%,1.0%.本方法简单、快速、准确、适用于控制牙周康胶囊的质量.  相似文献   

8.
研究建立测定氯地滴眼液中氯霉素和地塞米松磷酸钠含量的多波长直线回归法。在238.0 nm-290.0 nm波长区间,选择42个波长点作测定;采用计算机多波长直线回归程序作计算;不经分离,直接测定氯地滴眼液中氯霉素和地塞米松磷酸钠的含量。二者的平均回收率和相对标准偏差,分别为99.5%,1.1%和100.7%,1.3%。该方法简单、快速、准确、适用于氯地滴眼液的质量控制。  相似文献   

9.
研究建立牙周康胶囊中甲硝唑和芬布芬的系数倍率测定法。用BASIC语言编制程序选择最佳测定波长对,以消除二组分的相互干扰,不经提取分离同时测定牙周康胶囊中二组分的含量。甲硝唑的比耳线性范围为5.386-25.86μg/mL,r=0.9995,芬布芬的比耳线性范围为5.487~19.75μg/mL,r=0.9996。甲硝唑和芬布芬的平均回收率和相对标准偏差分别为100.4%,0.61%和100.2%,0.74%。该方法简便、快速、结果准确,可用于牙周康胶囊的质量控制。  相似文献   

10.
分光光度分析的CPA矩阵法编程   总被引:1,自引:0,他引:1  
一、方法原理利用光谱进行定量分析的基础是Beer-Lambert定律,即在单一组分体系中存在如下关系式: A=kC (1)其中A为吸光度,C为溶液浓度,k为比例常数。考虑到偏离Beer定律的情况,在上式中加入截距项修正: A=kC+k_0 (2)对于m个组分的体系,设有n个试样,测定的波长数为k,则可用矩阵形式表示为:  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
《计算机科学》2007,34(4):148-148
Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.  相似文献   

18.
为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.  相似文献   

19.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

20.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

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