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1.
Analytical chemistry is consolidating an important position within the framework of our modern industrial community; the frontiers of trace (and ultra-trace) analysis have expanded into new territories, thus demanding a constant change in our mode of thinking in a substance-related manner in analytical chemistry. An outline of the development of analytical chemistry during this century reveals a period of underdeveloped research and education followed by a current phase of impetuous advancement. However, as a result of increasingly antagonistic sectional convictions in the public mind concerning reservations against, as well as efforts towards, efficient technological progress, this advancement evokes new existential risks for analytical chemistry—viz. either to be used in an uncritical way or to fall into discredit following slogans like ‘high-performance analytical chemistry is to blame for it all!’ A much more constructive consideration says that risks can be estimated and evaluated solely by means of a highly efficient analytical chemistry, when used with a sense of responsibility. Analysts may help to clarify and to cope with the increasing fear of decreasingly smaller amounts of trace elements—in both adverse groups in our community. Strategies necessary to gain this end are outlined with regard to a methodological as well as a political platform.  相似文献   

2.
The present situation of analytical chemistry teaching within a chemistry curriculum is exemplified by the reformed chemistry curriculum in Germany. This approach is contrasted with teaching analytical chemistry within a novel curriculum in natural sciences termed ‘applied science’. The latter curriculum ensures a superior education in chemistry, physics, biology, mathematics and information science, thus gaining an integrated perspective of analytical chemistry.  相似文献   

3.
This paper aims to connect philosophy of chemistry, green chemistry, and moral philosophy. We first characterize chemistry by underlining how chemists: (1) co-define chemical bodies, operations, and transformations; (2) always refer to active and context-sensitive bodies to explain the reactions under study; and (3) develop strategies that require and intertwine with a molecular whole, its parts, and the surroundings at the same time within an explanation. We will then point out how green chemists are transforming their current activities in order to act upon the world without jeopardizing life. This part will allow us to highlight that green chemistry follows the three aforementioned characteristics while including the world as a partner, as well as biodegradability and sustainability concerns, into chemical practices. In the third part of this paper, we will show how moral philosophy can help green chemists: (1) identify the consequentialist assumptions that ground their reasoning; and (2) widen the scope of their ethical considerations by integrating the notion of care and that of vulnerability into their arguments. In the fourth part of the paper, we will emphasize how, in return, this investigation could help philosophers querying consequentialism as soon as the consequences of chemical activities over the world are taken into account. Furthermore, we will point out how the philosophy of chemistry provides philosophers with new arguments concerning the key debate about the ‘intrinsic value’ of life, ecosystems and the Earth, in environmental ethics. To conclude, we will highlight how mesology, that is to say the study of ‘milieux’, and the concept of ‘ecumeme’ proposed by the philosopher and geographer Augustin Berque, could become important both for green chemists and moral philosophers in order to investigate our relationships with the Earth.  相似文献   

4.
Structure elucidation of organic compounds is only one of the applications of mass spectrometry to chemistry. Important subjects are also mass spectrometric quantitative analysis of mixtures of inorganic and of organic compounds, determination of isotopes and related problems. In ‘Massenspektrometrie’, edited by H. Kienitz, all these applications are discussed together with an excellent introduction to the function of mass spectrometers and the techniques of measurement. This book contains a lot of information and stimulation for mass spectroscopists and chemists, and is especially recomended for use in analytical laboratories.  相似文献   

5.
Touch‐screen computers are emerging as a popular platform for many applications, including those in chemistry and analytical sciences. In this work, we present our implementation of a new NMR ‘app’ designed for hand‐held and portable touch‐controlled devices, such as smartphones and tablets. It features a flexible architecture formed by a powerful NMR processing and analysis kernel and an intuitive user interface that makes full use of the smart devices haptic capabilities. Routine 1D and 2D NMR spectra acquired in most NMR instruments can be processed in a fully unattended way. More advanced experiments such as non‐uniform sampled NMR spectra are also supported through a very efficient parallelized Modified Iterative Soft Thresholding algorithm. Specific technical development features as well as the overall feasibility of using NMR software apps will also be discussed. All aspects considered the functionalities of the app allowing it to work as a stand‐alone tool or as a ‘companion’ to more advanced desktop applications such as Mnova NMR. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

6.
7.
The ISO technical report 14187 provides an introduction to (and examples of) the information that can be obtained about nanostructured materials by using surface analysis tools. In addition, both general issues and challenges associated with characterizing nanostructured materials and the specific opportunities and challenges associated with individual analytical methods are identified. As the size of objects or components of materials approaches a few nanometers, the distinctions among ‘bulk’, ‘surface’, and ‘particle’ analysis blur. This technical report focuses on issues specifically relevant to surface chemical analysis of nanostructured materials. The report considers a variety of analysis methods but focuses on techniques that are in the domain of ISO/TC 201 including Auger electron spectroscopy, X‐ray photoelectron spectroscopy, secondary ion mass spectrometry, and scanning probe microscopy. Measurements of nanoparticle surface properties such as surface potential that are often made in a solution are not discussed. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

8.
Green chemistry and sustainability is now entirely encompassed across the majority of pharmaceutical companies and research labs. Researchers’ attention is careworn toward implementing the green analytical chemistry principles for more eco‐friendly analytical methodologies. Solvents play a dominant role in determining the greenness of the analytical procedure. Using safer solvents, the greenness profile of the methodology could be increased remarkably. In this context, a green chromatographic method has been developed and validated for the simultaneous determination of phenylephrine, paracetamol, and guaifenesin in their ternary pharmaceutical mixture. The chromatographic separation was carried out using monolithic column and green solvents as mobile phase. The use of monolithic column allows efficient separation protocols at higher flow rates, which results in short time of analysis. Two‐factor three‐level experimental design was used to optimize the chromatographic conditions. The greenness profile of the proposed methodology was assessed using eco‐scale as a green metrics and was found to be an excellent green method with regard to the usage and production of hazardous chemicals and solvents, energy consumption, and amount of produced waste. The proposed method improved the environmental impact without compromising the analytical performance criteria and could be used as a safer alternate for the routine analysis of the studied drugs.  相似文献   

9.
The main aim of this study is to develop novel polymer modified glass-ionomer cement (GIC) glasses utilizing click chemistry and RAFT polymerization. These novel glasses can serve as a platform to improve the properties of GIC's by incorporating chemistries and formulations that are not normally compatible with GIC's. Aluminofluoro-silicate glasses utilized in glass-ionomer dental cements were coated with azide terminated silane groups. In addition, a copolymer of acrylic acid-itaconic acid containing alkyne groups was synthesized by RAFT polymerization and was coupled via ‘click’ chemistry with the azide-coated GIC glass particles. FT-IR spectroscopy was used to characterize the synthesized materials and to confirm completion of the ‘click’ coupling reaction. The experimental cements cured, demonstrating that these modified glasses could be utilized in GIC formulations. The long setting and working times compared to control groups indicate that further improvements are necessary to fully utilize this chemistry. Our initial results in this study demonstrated the successful application of click chemistry in developing novel dental restorative materials, specifically glass-ionomer cements.  相似文献   

10.
马乐  张莹 《化学教育》2021,42(7):22-26
化学教材作为最重要的化学教学资源之一,其中丰富的英文资源潜藏着重要价值,合理应用教材中英文教学资源,在提升化学教师的专业能力、推动学生思维发展、培养学生人文精神等方面都具有积极意义。梳理新人教版高中化学必修1和必修2中的英文教学资源,将其归纳概括为3大类:与基本概念和原理相关的英文教学资源、化学物质名词英文教学资源和常见的化学元素英文教学资源。对3类英文教学资源的内容及特质进行列举分析,同时对其应用进行探讨,提出相关建议。  相似文献   

11.
Modern analytical chemistry is the important professional course for graduate students of analytical chemistry and the related majors. It is the continuation and promotion of knowledge of analytical chemistry course and the key course to improve the scientific research ability of students. The course includes modern separation science, modern electroanalytical chemistry, modern photoanalytical chemistry and advanced analytical chemistry. It is an important guarantee for improving teaching quality to carry out teaching reform of modern analytical chemistry. In the paper, starting from the construction of teaching team, the modern analytical chemistry course group including four courses was set up for the first time. The course contents are reorganized. The teaching methods are optimized and coordinated. The courses are constructed collectively, including reforming the teaching mode and teaching method, editing textbook appropriately and setting up website with a variety of teaching materials. Therefore, the teaching quality can be guaranteed and the disciplinary fundamentals for research work of students can be strengthened.  相似文献   

12.
13.
This paper analyses Richard Bader’s ‘operational’ view of quantum mechanics and the role it plays in the the explanation of chemistry. I argue that QTAIM can partially be reconstructed as an ‘austere’ form of quantum mechanics, which is in turn committed to an eliminative concept of reduction that stems from Kemeny and Oppenheim. As a reductive theory in this sense, the theory fails. I conclude that QTAIM has both a regulatory and constructive function in the theories of chemistry.  相似文献   

14.
《Tetrahedron: Asymmetry》2006,17(23):3288-3293
Based on ‘click chemistry’ conditions, a class of novel, facile, versatile pyrrolidine-based triazole derivatives were prepared, and proved to be efficient catalysts for the highly diastereoselective and enantioselective Michael addition of ketones to nitroalkenes. The Cu(I)-catalyzed 1,3-dipolar ‘click’ azide–alkyne cycloaddition provides modular and tunable features for the pyrrolidine-based triazole organocatalysts, and the resulting triazole moiety can serve as a phase tag to complete the reaction in water with an excellent yield and high enantiomeric excess.  相似文献   

15.
A new chronology is introduced to address the history of chemistry, with educational purposes, particularly for the end of the twentieth century and here identified as the fifth chemical revolution. Each revolution are considered in terms of the Kuhnian notion of ‘exemplar,’ rather than ‘paradigm.’ This approach enables the incorporation of instruments, as well as concepts and the rise of new subdisciplines into the revolutionary process and provides a more adequate representation of such periods of development and consolidation. The fifth revolution developed from 1973 to 1999 and is characterized by a deep transformation in the very heart of chemistry. That is to say, the size and type of objects (substances), the way in which they must be done and the time in which they are transformed. In one way or another, chemistry’ limits had been set out.  相似文献   

16.
Regular monitoring of arsenic (As) in groundwater is crucial from public health perspectives as millions of people are suffering due to use of contaminated aquifer water for drinking purposes. The routine analyses, especially in developing nations, are mostly done in localised government/non-government laboratories with limited resources, having the target of analysing large number of samples in each run. Thus apart from analytical sensitivity, cost-effectiveness of the method and eco-friendliness of the experimental operation are key surreptitious factors. This demands optimisation of total As measurement methods and finding a method that gives ‘optimum benefit’ considering all these factors together. The present study therefore evaluates four common As (total) measurement methods [iodometric-colorimetric method, silver diethyl dithiocarbamate method, molybdenum blue method and hydride generation atomic absorption spectrophotometric (HG-AAS) method] practised in the Bengal Delta Plain, in view of their analytical sensitivity, related environmental hazard and experimental costs. It was found that the HG-AAS method is analytically more sensitive, whereas the iodometric-colorimetric method and the molybdenum blue method are better choices in terms of eco-friendliness and cost-effectiveness, respectively. However, when all three factors (analytical reliability, environmental hazard and cost) are considered simultaneously, the molybdenum blue method was found to be placed first in the ‘optimum performance rank’ list. It was also found that both environmental hazard and cost play a more crucial role than analytical reliability, although this is case specific and would differ from place to place around the globe. Finally based on the results, we have hypothesised a water testing strategy for developing countries such as India where the molybdenum blue method can be adapted as a screening method and later the HG-AAS method can be used to precisely identify the groundwater samples with As concentration below the WHO drinking water guideline value of 10 μg/L.  相似文献   

17.
‘Supramolecular photochemistry’ (SP) deals with a study of the properties of molecules in their excited states where the medium plays a significant role. While ‘molecular photochemistry’ (MP) deals with studies in isotropic solution, the SP deals with reactant molecules that interact weakly with their surroundings. The surroundings in general are highly organized assemblies such as crystals, liquid crystals, micelles, and host–guest structures. The behavior of exited molecules in SP unlike in isotropic solution is controlled not only by their inherent electronic and steric properties but also by the immediate surroundings. The weak interactions that control the chemistry include van der Walls, hydrophobic, CH⋯π, π⋯π and several types of hydrogen bonds. In this review the uniqueness of SP compared to MP is highlighted with examples chosen from reactions in crystals, micelles and host–guest assemblies. In spite of distinctly different structures (crystals, micelles, etc.) the influence of the medium could be understood on the basis of a model developed by G.M.J. Schmidt for photoreactions in crystals. The principles of reaction cavity model are briefly outlined in this review. There are a few important features that are specific to SP. For example, highly reactive molecules and intermediates could be stabilized in a confined environment; they enable phosphorescence to be observed at room temperature and favor chiral induction in photochemical reactions. Using such examples the uniqueness of SP is highlighted. The future of SP depends on developing efficient and unique catalytic photoreactions using easily available reaction ‘containers’. In addition, their value in artificial photosynthesis should be established for SP to occupy a center stage in the future.  相似文献   

18.
For more than half a century we have been using activation of stable isotopes to determine chemical elements, and significant contributions have been made to a variety of scientific subjects. Nevertheless, activation analysis has not yet become integrated in the field of chemical analysis, and therefore the special features characteristic of activation analysis have not been fully realised in analytical chemistry. At the same time basic chemical knowledge has only to a limited extent been utilised in the development of analytical methods based on activation. This situation has only now become painfully clear, when a world-wide requirement is being made to express the uncertainty of analytical results in accordance with the BIPM philosophy. The identification and estimation of all uncertainty components needed to produce a reliable uncertainty budget requires the combined efforts of all parties. An attempt is here made to extrapolate current trends for the expression of uncertainty in activation and analysis into the future and to show, how the implementation of the BIPM Guidelines with respect to correction for all known or suspected biases, achievement of statistical control, and full traceability, can help bringing analytical chemistry into its rightful position as a scientific discipline in the field of metrology.  相似文献   

19.
Before teaching a course, the instructor must identify what she or he intends for the students to learn. For most analytical chemistry instructors, this usually involves an assessment of what methods and techniques to include and at what depth to cover them. There are many other skills, though, that will be important to students for their future success. Most college classes in analytical chemistry are taught in a lecture format. Techniques that can be used to improve the learning that can occur during a lecture are described. An alternative to lecturing is the use of cooperative learning. Cooperative learning offers the potential to develop skills such as teamwork, communication, and problem-solving that are more difficult to impart in a lecture format. The laboratory component of analytical chemistry courses is often an underutilized learning resource. More often than not, the lab is used to demonstrate fundamental wet and instrumental analysis techniques and develop rudimentary laboratory skills. The analytical lab should also be used to develop meaningful problem-solving skills and to demonstrate and have students participate in the entire analytical process. Ways of enhancing the analytical laboratory to include more global skills that are important to career success are described.Received January 12, 2003; accepted March 7, 2003 Published online July 16, 2003  相似文献   

20.
Two novel azido‐derivatives of closo‐dodecaborate anion with hydrophobic and hydrophilic spacers were prepared by reaction of tetrabutylammonium azide with cyclic oxonium derivatives of the closo‐dodecaborate anion. The compounds prepared can be regarded as precursors of derivatives of closo‐dodecaborate anion with amino group at the terminal position of a spacer or as building blocks for ‘click chemistry’, which are useful for preparation of various conjugates with targeting molecules. A concentration dependence of the 11B NMR spectra of functionalized derivatives of closo‐dodecaborate anion was discovered, which is of great importance for analytical purposes. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

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