Analysis of Some Characteristics of Polymer Concrete by Nontraditional Methods

An assessment of the surface potential of polymer concrete by using the method of sclerometry in combination with microhardness measuring was carried out. It is shown that a gelcoat layer on a polymerconcrete surface increases the resistance of such a surface to scratching and its microhardness is more twice as high as the microhardness of the untreated polymer-concrete surface.     

Nontraditional Extraction Systems

Extraction systems with water and organic phases can be differentiated due to varied formation causes systems with limited mutual solubility of water and organic solvent are more often, energy of interaction between water and organic molecules is not more than 2RT.     

Nontraditional variants of thin layer chromatography

New chamberless thin layer chromatography methods are evaluated and systematized. The terminology of the new methods is discussed.     

Analytical Dispersion Force Calculations for Nontraditional Geometries

Presented in this paper are first-principle-based approximate macroscopic models of the van der Waals adhesion force for a variety of particle shapes interacting with an infinite cylinder. In particular, expressions for the van der Waals adhesion force and interaction energy are developed for a (1) spherical particle/infinite cylinder, (2) disk-like particle/infinite cylinder, (3) disk-like particle oriented edgewise to an infinite cylinder, and (4) a deformed slice/infinite cylinder. The models presented depict expected trends in the behavior of both the force of adhesion and the interaction energy between different geometric configurations. These results are also used to demonstrate the impact of contact time on the adhesion force for cylindrical fibers in contact with a disk-shaped particle. After long time intervals where the disk-like particles have remained in contact with the cylinder, the adhesion force may lead to significant deformation of the attached particle. Hence, the adhesion force for a fourth geometric set which represents the most likely scenario for attached particles with long contact times is developed. As will be shown, this scenario results in the highest values of adhesion force and interaction energy. Copyright 2000 Academic Press.     

Computational Analysis of Quadrupole Mass Filters Employing Nontraditional Waveforms

Quadrupole mass filters using non-sinusoidal driving potentials present exciting opportunities for new functionality. Predicting figures of merit like resolving power and transmission efficiency helps characterize these emerging devices. To this end, matrix methods of solving the Hill equation of ion motion are employed to calculate stability diagrams and pseudopotential well depth maps in the a,q plane for arbitrary waveforms. The theoretical resolving power and well depth of digital, trapezoidal and sinusoidal mass filters are compared. Simplified expressions for digital mass filter operation are presented.

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甲亚胺与姜黄素测定土壤有效硼方法的对比研究

土壤有效硼是决定土壤供硼能力的重要指标，目前中国多以沸水浸提土壤，并用姜黄素比色测硼值作为作物硼营养丰缺诊断指标．但在长期实践中，发现作物硼营养状况与热水溶性硼的相关性不稳定，同时测定值重现性不良。为提高作物硼营养诊断和预测的准确性，本研究通过０．０１ｍｏｌ／ＬＣａＣｌ２在２６０℃、３５ｍｉｎ浸提土壤条件下，用甲亚胺比色与沸水浸提，姜黄素比色法测定土壤有效硼的对比研究，证明甲亚胺法测定结果稳定，操作方法简便，适用于低硼土壤的大批量试样的自动分析。为甲亚胺测硼方法的推广应用，本研究已研制甲亚胺粉状试剂获得成功，与进口甲亚胺比较，性能完全一致。     

蝶呤类化合物分析方法研究进展

本文概述了国内外蝶呤类化合物分析方法的研究现状,包括高效液相色谱法、荧光分析法、免疫分析法、毛细管电泳法等,同时对人体的尿液和血液等样品的前处理方法进行了介绍。引用文献49篇。     

薄层色谱展开方法的几处改进

介绍了几种薄层色谱展开方法，包括中途展开、接力展开、多维接力展开、改进二维展开等，还介绍了一种简单的下行展开的操作方式以及关键部件的制作方法。     

邻苯二甲酸酯类增塑剂分析方法进展

本文详细介绍了国内外邻苯二甲酸酯类增塑剂检测方法的研究进展。对环境（大气、水体、土壤）中和塑料产品中的邻苯二甲酸酯的样品的预处理方法和检测技术作了综述,并提出了检测中存在的问题和研究前景。     

A Nontraditional Laboratory Proposal: Investigating the Kinetics of a Chemical Reaction

This paper presents an unstructured laboratory in which students determine the rate law for a reaction. We have selected for this investigation the reaction between magnesium and hydrochloric acid. The general goal of the proposal is threefold: (1) to increase students interest in science during first-year chemistry; (2) to create a more active learning environment where students can learn and do science as scientists; and (3) to develop and promote critical thinking, analytical reasoning, collaboration, and interactive discussion based on a scientific problem. This laboratory has proven to be effective because the students, with some guidance from the instructor, were able to (1) state one or more hypotheses related to the problem under study (chemical kinetics); (2) design procedures and strategies to answer specific questions; and (3) establish methods to manipulate and interpret the data. Finally, the students were required to write a report. In this way, the laboratory promotes creativity and improves students critical thinking in an introductory course of university general chemistry.     

血液中苯丙氨酸的测定方法研究进展

高效、简便、快速测定血液中苯丙氨酸含量在医学上尤其是对新生儿的苯丙酮尿症的筛查有着重要的意义；本文就血液中苯丙氨酸的测定方法研究进展进行了综述，内容包括：细菌抑制法、荧光法、高效液相色谱法、气相色谱—质谱联用、质谱—质谱联用、毛细管电泳、酶／比色法以及酶电极法等。     

Theoretical Study of the Nontraditional Enol‐Based Photoacidity of Firefly Oxyluciferin

A theoretical analysis of the enol‐based photoacidity of oxyluciferin in water is presented. The basis for this phenomenon is found to be the hydrogen‐bonding network that involves the conjugated photobase of oxyluciferin. The hydrogen‐bonding network involving the enolate thiazole moiety is stronger than that of the benzothiazole phenolate moiety. Therefore, enolate oxyluciferin should be stabilized versus the phenolate anion. This difference in strength is attributed to the fact that the thiazole moiety has more potential hydrogen‐bond acceptors near the proton donor atom than the benzothiazole moiety. Moreover, the phenol‐based excited‐state proton transfer leads to a decrease in the hydrogen‐bond acceptor potential of the thiazole atoms. The ground‐state enol‐based acidity of oxyluciferin is also studied. This phenomenon can be explained by stabilization of the enolate anion through strengthening of a bond between water and the nitrogen atom of the thiazole ring, in an enol‐based proton‐transfer‐dependent way.     

Nontraditional nitrogen-containing macroheterocyclic systems with a high degree of conjugation (review)

Methods for the classification and codification of the principal types of nitrogen-containing macroheterocyclic systems with a high degree of conjugation and the schemes for their synthesis are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 3–18, January, 1982.     

合成生物降解性聚酯研究的进展

对近年来采用化学法,主要是缩合聚合法及开环聚合法,合成生物降解性聚酯的研究进展作了综述。     

共轭亚油酸制备方法的研究进展

依据反应机理和原料对具有生理活性的共轭亚油酸的制备与纯化方法进行了综述。详细讨论了共轭多烯酸(尤其是共轭亚油酸)的合成方法的研究进展，依据目标产物的收率、纯度及成本对合成或制备方法进行了比较和评价。     

生物时空振荡分析法

一切生物体系本身均存在固有的非线性、非平衡振荡行为。无论是活性酶体系,线粒体体系还是细胞体系都存在许多自组织的时空振荡现象。细胞分析是研究生命过程的切入点,也是现代分析化学研究的前沿和热点。本文评述了以耗散结构为基础,以时空振荡为依托的生物时空振荡分析方法及其特点,重点评述了酶振荡、钙振荡、糖酵解振荡在细胞代谢分析中应用的现状。     

量子力学和分子力学组合方法及其应用

QM/MM组合方法在研究凝聚态中的化学反应及生物大分子的结构和活性之间的关系等方面已取得重要进展。这一方法的要点在于将大体系配分成几部分,根据需要对不同部分进行不同级别的处理,因此既利用了量子力学的精确性,又利用了分子力学的高效性。对QM/MM组合理论及其一些最新进展作一简单介绍,并以最近进行了几个工作为例说明QM、MM组合方法的应用。     

手性吲哚啉衍生物合成方法的研究进展

吲哚啉衍生物广泛存在于自然界中,因具有多种生物学活性而引起广泛关注.近年来,手性吲哚啉衍生物成为此领域的研究热点,也报道了多种相应的合成方法,主要包括动力学拆分、不对称合成、手性合成子策略等,不对称Domino级联反应作为近年来发展较快的领域,也引起了广泛关注,对以上合成方法加以综述.