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1.
色谱峰纯度的定性方法   总被引:8,自引:2,他引:6  
黄芳  康继宏  郁建  胡育筑 《色谱》1995,13(1):33-37
较系统地介绍了近年来国内外文献中有关色谱峰纯度的定性方法──仪器方法和化学计量学方法。仪器方法重点介绍了归一化比较光谱、吸收比法、光谱抑制法及导数技术。化学计量方法介绍了主成分分析法和渐近因子分析法。通过对文献方法和应用的简单介绍,比较了各种方法的特点及优缺点,总结了规律。  相似文献   

2.
即时测试(PoCT)方法的应用满足了食品、检疫、临床等多方面的快速、准确、简便的检测需求。碳点(CDs)作为一种新型的纳米材料,因易于制备、粒子尺度小、生物相容性好、低毒而被广泛应用于各种PoCT方法中。基于此,介绍了CDs的制备方法和表征方法,从食品安全、检疫与临床检测方面综述了CDs在PoCT中的应用,并对基于CDs的PoCT方法的发展进行了展望(引用文献95篇)。  相似文献   

3.
简要介绍了线性、星形和环状单分散共轭齐聚物的主要合成方法,并对不同方法的优缺点做了简要评述.其中,线性单分散共轭齐聚物的合成方法主要有4种,即控制聚合方法,发散合成方法,发散/收敛合成方法和指数增长合成方法.在星状单分散共轭齐聚物方面,主要介绍了两种苯环成环反应的应用.环状共轭齐聚物的合成主要介绍了聚合过程中的成环反应、线性共轭齐聚物的分子内环化反应和模板导向环化反应.  相似文献   

4.
综述了近20年来。水体中铊的富集分离方法,如物理方法、化学方法、生物方法和电化学方法的研究现状,讨论了不同方法的优缺点,展望了水体中铊富集分离方法的发展方向(引用文献42篇)。  相似文献   

5.
纳米银粒子的制备方法进展   总被引:1,自引:0,他引:1  
综述了纳米银粒子的制备方法,包括物理方法和化学方法。  相似文献   

6.
综述了甲醛测定方法(包括光谱法、电化学法、色谱法、生物学方法、化学方法和其他方法)的研究进展,并对其发展前景进行了展望(引用文献55篇)。  相似文献   

7.
伍星 《中国稀土学报》2006,24(Z2):137-140
回顾了我国稀土化学分析方法标准化工作的历史,并介绍了近年来我国稀土化学分析方法标准化工作的进展.指出目前已初步形成了较为完善的稀土化学分析方法国家标准体系.  相似文献   

8.
从还原剂和还原方法这两个方面综述了近些年来绿色还原氧化石墨烯的若干方法,对一些天然的还原剂的应用及结果进行了描述,分析了这些方法的优缺点并给出了部分反应可能的机理,还对一些新型的环境友好型的还原方法也进行了评价。同时,对于还原氧化石墨烯的研究提供了新的思路和展望。  相似文献   

9.
分子对接方法加快了药物开发周期,具有快速、准确度高等优点.本文详述了分子对接方法的基本原理,及分子对接空间和能量的匹配要求和优化时的各种方法.综述了该方法在药物设计、药理分析和探测生命体系等方面的应用.  相似文献   

10.
葡萄糖生物传感器以其灵敏度高、选择性好、反应速度快以及稳定性好等优点吸引了许多研究者的关注。 本文将已发表的一些葡萄糖检测方法分为两类:葡萄糖酶生物传感器检测方法与无酶葡萄糖生物传感器检测方法,简要介绍了这2种检测方法的一些研究进展,并对葡萄糖检测方法的发展前景进行了展望。  相似文献   

11.
近年来,基于三维图像的人脸识别技术已经取得了很大进展,在约束环境下也能获得很好的识别性能,但仍受限于姿态、表情等因素,需要从算法上改进才能解决其影响。本文分别从基于空域直接匹配、基于局部特征匹配和基于整体特征匹配3个角度出发,对人脸匹配算法以及融合算法进行了研究,列出了部分改进算法的实验结果,并分析了算法有效性的原因,总结了目前面临的三维人脸识别算法难以突破的一些困难及未来的研究趋势。  相似文献   

12.
示波分析在中国的发展:Ⅰ.示波分析法   总被引:5,自引:1,他引:5  
宋俊峰 《分析化学》1998,26(6):627-632
示波分析是在我国新近发展起来的电分析新领域,它有十大类技术:示波计时电位法,改进的示波计时电位法,倒数示波计量电位法,示波电位法,示波伏安8法。示波分析包括示波滴定和示波测定两大分支。本文综述示波分析的方法和特点。  相似文献   

13.
The concept of flow “fine” synthesis, that is, high yielding and selective organic synthesis by flow methods, is described. Some examples of flow “fine” synthesis of natural products and APIs are discussed. Flow methods have several advantages over batch methods in terms of environmental compatibility, efficiency, and safety. However, synthesis by flow methods is more difficult than synthesis by batch methods. Indeed, it has been considered that synthesis by flow methods can be applicable for the production of simple gasses but that it is difficult to apply to the synthesis of complex molecules such as natural products and APIs. Therefore, organic synthesis of such complex molecules has been conducted by batch methods. On the other hand, syntheses and reactions that attain high yields and high selectivities by flow methods are increasingly reported. Flow methods are leading candidates for the next generation of manufacturing methods that can mitigate environmental concerns toward sustainable society.  相似文献   

14.
15.
 There is much discussion in chemical metrology about the definition of primary methods of measurement, just as a couple of years ago there was debate about its predecessors, absolute methods and definitive methods. It is argued in this paper that the designation of certain methods as being primary only makes sense if there is an outstanding property identified that is common to all primary methods, and not present for all non-primary methods. The aim to identify primary methods should not blur our notion that it is the good practice of analytical chemistry that produces good results, not a particular method of analysis.  相似文献   

16.
简单介绍了生物柴油的生产原料,综述了用废弃油脂生产生物柴油的现状和方法。废弃油脂生产生物柴油的方法主要有物理法和化学法,物理法主要有掺和法和微乳法,化学法主要有热裂解法和酯交换法。目前生产中采用化学法的酯交换法、以酸碱两步催化法的工艺为主,而生物酶法和超临界法是研究热点。  相似文献   

17.
Ammonium (NH4+) and ammonia (NH3) in aquatic ecosystems are of great interest to environmental scientists because they can be used to study the nitrogen cycle and as water quality indicators. Analytical separation methods developed in recent decades have been used widely to determine NH4+ and NH3 in aqueous solutions. This review presents an overview of state-of-the-art separation methods and analytical techniques for determining NH3/NH4+ in natural water, including chromatographic methods, electrophoretic methods, extraction methods, membrane-based gas diffusion methods, membraneless gas diffusion methods, passive sampling methods, and paper-based analytical methods. Common detection techniques that can be used in conjunction with particular separation methods are described, phase-transfer strategies (liquid-liquid, liquid-solid, liquid-membrane-liquid, and liquid-gas-liquid methods) are highlighted, and the strengths and weaknesses of the separation methods are discussed. The outlook, challenges, and expected future developments in the field of separation methods for determining NH4+ and NH3 in natural water are presented.  相似文献   

18.
橡胶贮存寿命预测方法研究进展与思考建议   总被引:5,自引:0,他引:5  
概述了用数学模型法预测橡胶贮存寿命的方法,包括阿伦尼斯模型,用ASTM D412评估橡胶拉伸性能,应力应变老化模型,压缩永久变形的预测方法,橡胶疲劳寿命损伤模型,用有限元法考核橡胶的裂纹长度与抗裂能之间的关系,基于叠加原理的寿命预测模型等,针对上述模型预测研究结果提出了相关思考建议。认为以老化动力学为基础预测材料寿命的数学模型法发展非常迅速,建议深入研究并拓宽应用;在透彻了解和掌握必需的分子结构参数的基础上,如果结合计算机技术模拟长期贮存或使用条件,对橡胶老化反应机理的研究可能是一个有前景的发展方向。  相似文献   

19.
Special Session B at the 29th Symposium on Biotechnology for Fuels and Chemicals was the first invited session at this symposium devoted to analytical methods. The special topic was added in response to numerous requests for information on new and innovative methods that could be applied in the growing renewable fuels industry. Presentation topics include analytical methods for the characterization and analysis of maize traits, tools for investigating cell wall limitations to enzymatic degradation, methods for customizing enzyme cocktails for biomass, new techniques for the analysis of carbohydrates, analytical methods that enhance our understanding of pretreatment, improved methods for monitoring process intermediates, and published standard analytical methods for biomass conversion processes.  相似文献   

20.
There are many methods for analyzing solid-state kinetic data. They are generally grouped into two categories, model-fitting and isoconversional (model-free) methods. Historically, model-fitting methods were widely used because of their ability to directly determine the kinetic triplet (i.e., frequency factor [A], activation energy [E(a)], and model). However, these methods suffer from several problems among which is their inability to uniquely determine the reaction model. This has led to the decline of these methods in favor of isoconversional methods that evaluate kinetics without modelistic assumptions. This work proposes an approach that combines the power of isoconversional methods with model-fitting methods. It is based on using isoconversional methods instead of traditional statistical fitting methods to select the reaction model. Once a reaction model has been selected, the activation energy and frequency factor can be determined for that model. This approach was investigated for simulated and real experimental data for desolvation reactions of sulfameter solvates.  相似文献   

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