Search results for "airs"
showing 10 items of 194 documents
Amine basicity: measurements of ion pair stability in ionic liquid media
2007
Abstract The stability constants relevant to the formation of amine/p-nitrophenol ion pairs have been determined in [bmim][BF4] solution, in the presence of butylamine, piperidine, and triethylamine, by using spectrophotometric measurements. In order to evaluate how the ion pair stability is affected by ionic liquid structure, piperidine has been chosen as model amine for studies in [bmim][PF6], [bmim][NTf2], [bm2im][NTf2] and in several [bmim][BF4]/1,4-dioxane binary mixtures. Data obtained in ionic liquid solutions have been compared with those previously reported in conventional organic solvents.
Über den einfluß der monomerkonzentration auf die geschwindigkeitskonstante kw der monomeraddition an das ionenpaar eines „lebenden” polymeren
1966
Fur den Zahlenwert der Geschwindigkeit skonstante kw(±) fanden die Arbeitsgruppen in Mainz und Syracuse voneinander abweichende Werte. Es wurde angenommen, das die Ursache dieser Diskrepanz die um Grosenordnungen verschiedenen Konzentrationsbereiche sind, in denen die Messungen ausgefuhrt wurden. Nachfolgend wird ein Reaktionsschema vorgeschlagen und kinetisch durchgerechnet, welches eine schneller polymerisierende Komplexverbindung zwischen dem Ionenpaar und dem Monomeren voraussetzt. The rate constant kw(±) for the addition of monomer to the ion pair of a „living” polymer was measured by workers in Mainz and in Syracuse. Their results lack agreement. It was assumed that this disparity is …
Extractive Spectrophotometric Determination of Ondansetron by Ion-Pair Formation with Bromocresol Green
1996
Abstract An empirical spectrophotometric procedure for the determination of the antiemetic ondansetron is carried out. The method is based on the formation of a 1:1 ion pair with bromocresol green in the pH range over 3.2 – 4.4, extraction into chloroform layer and spectrophotometric measurement at 420.8 nm. The calibration graph is linear over the range 0.1 – 20 μg ml−1 ondansetron, with a relative standard deviation of 2.7%; the influence of foreign substances is also studied. The method is applied to ondansetron determination in human urine.
The Factors Influencing Academic Affairs Services Management at the National University of Laos and Lucian Blaga University of Sibiu, Romania
2013
This research aims are to investigate the attitude levels of staff's and students' on the motivation, effectiveness towards the academic affairs services management at the faculty of Economics and Business Management, DongDok campus in the National University of Laos, and the faculty of Economic Sciences and faculty of Sciences, Sibiu campus in Lucian Blaga University of Sibiu, Romania. There were 220 participants, five groups; presidents, deans, heads of departments, lecturers and students. The five-point Likert scale rating questionnaires were used to collect data. The SPSS version 20 was used to perform the needed analysis for reaching the proposed aims. In this regard, univariate and bi…
$varphi$-pairs and common fixed points in cone metric spaces
2008
In this paper we introduce a contractive condition, called $\varphi \textrm{-}pair$, for two mappings in the framework of cone metric spaces and we prove a theorem which assures existence and uniqueness of common fixed points for $\varphi \textrm{-}pairs$. Also we obtain a result on points of coincidence. These results extend and generalize well-known comparable results in the literature.
Common fixed points in cone metric spaces for CJM-pairs
2011
Abstract In this paper we introduce some contractive conditions of Meir–Keeler type for two mappings, called f - M K -pair mappings and f - C J M -pair (from Ciric, Jachymski, and Matkowski) mappings, in the framework of regular cone metric spaces and we prove theorems which guarantee the existence and uniqueness of common fixed points. We give also a fixed point result for a multivalued mapping that satisfies a contractive condition of Meir–Keeler type. These results extend and generalize some recent results from the literature. To conclude the paper, we extend our main result to non-regular cone metric spaces by using the scalarization method of Du.
Kinetic control in the chiral recognition of three-bladed propellers
2010
The ion pair of the stereolabile C(3)-symmetric, i(+)o proton complex [1H](+) of diaza-macropentacycle 1 and the configurationally stable Delta-TRISPHAT ([Delta-3](-)) anion exists in the form of two diastereomers, namely, [Delta-(1.H)][Delta-3] and [Lambda-(1.H)][Delta-3], the ratio of which, in terms of diastereomeric excess (de) decreases in the order [D(8)]THF (28%)CD(2)Cl(2) (22%)CDCl(3) (20%)[D(8)]toluene (16%)C(6)D(6) (7%)[D(6)]acetone (0%) at thermodynamic equilibrium. Except in the case of [D(6)]acetone, the latter is reached after a period of time that increases from 1 h ([D(8)]THF) to 24 h (CDCl(3)). Moreover, the initial value of the de of [1.H][Delta-3] in CDCl(3), before the t…
Competing economies of worth in a multiagency music and reconciliation partnership: The Sri Lanka Norway Music Cooperation (2009-2018)
2020
The Sri Lanka Norway Music Cooperation (2009–2018) was launched to ‘stimulate the performing arts in Sri Lanka, thus contributing to the peace and reconciliation process’ in the aftermath of almost three decades of civil war between the Tamil minority and Sinhala majority populations of the island. Funded by the Norwegian Ministry of Foreign Affairs, the project had many local and international stakeholders, from artists and civil society organisations, to government institutions, to a general public eager for enrichment through arts and culture. But despite high engagement and financial investment, the achievements of the SLNMC were generally unremarkable and short-term. This article argue…
What Could Mean âTo Think in Spanishâ?
2008
The expression “to think in Spanish” could be understand in two different senses: as an exhortation or as a description of an state of affairs. In the first sense it has a normative character. It can means something like “we must think in Spanish!”. In the second case, it would be a more or less vague formulation about the existence of a relevant intelectual tradition in the spanish language. The first interpretation is misleading and can have excluding or trivial consequences. The second one is partially true. I propose a third interpretation: “to think in Spanish” could be understood as an invitation not to forget our Spanish-speaking environment in the double sense of the physical and in…
The Cultural Dimension of Spanish Universities: The state of the issue
2020
The cultural dimension of Spanish universities has changed markedly, especially since the restoration of democracy in Spain in the late 1970s. This study reflects on the terminology and the historical evolution of Spanish universities, comparing their development within a broader world context. It also analyses the present state of affairs through two complementary pieces of field work. The paper concludes by examining the issues and hurdles that until recently were the third dimension of university life after teaching and research.