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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Language, action and polity

Bowden, H. January 1984 (has links)
No description available.
2

Aspects of pure quantum chromodynamics on large lattices

Ford, I. J. January 1987 (has links)
No description available.
3

Teacher involvement in system policy formulation

Mugridge, Karen, n/a January 1998 (has links)
Policy formulation is a complex process involving many stakeholders. Teacher involvement in this process is vital if policies are to be successfully implemented at the classroom level. An understanding of the factors that affect teacher involvement in policymaking may assist in enhancing teacher involvement in future policy development. This study investigated teacher perceptions of their involvement in system po1icy formulation in relation to eight areas: the complex policy process, political / economic influences, teacher empowerment and morale, willingness, relationship with the governing body, opportunities, support / encouragement and implementation. Teachers from four primary schools and one high school were involved in the study. A questionnaire was completed by 68 respondents and a sub-sample of 8 participated in a semi-structured interview. The main findings of the study show that teachers are willing to become involved in the policy process, however, are inhibited by ineffective information flows (Kennedy: 1992) (Fullan:1994) (Waugh & Godfrey: 1995), lack of support (Short: 1994), knowledge (Gamoran:1994), and awareness of opportunities (Pajak:1992).
4

Applications of multivariate calibration models and factor analysis to spectroscopic data

Rogers, Louise Jennifer January 1998 (has links)
No description available.
5

Modelling and optimisation of pharmaceutical formulations and processes

Zolotariov, Eyal January 2001 (has links)
No description available.
6

The effect of wet granulation on the physico-mechanical characteristics of microcrystalline cellulose

Chatrath, Meena January 1992 (has links)
No description available.
7

The Effect of Drug Formulation on in vitro Performance Indices for Metered-Dose Inhalers with Regards to Varying Mouth-Throat Models

Fazel, Mohammad, Myrdal, Paul, Sheth, Poonham January 2013 (has links)
Class of 2013 Abstract / Specific Aims: To elucidate the effect of the use of three different inlet configurations, percent ethanol in formulation, and propellant used on the percent respirable drug and MMAD of aerosolized particles from MDIs that contained beclomethasone dipropionate (BDP). Methods: The inlet configurations assessed in this study were the United States Pharmacopeia (USP) throat, the Alberta idealized mouth-throat replica (biological throat), and a large volume spacer (globe). ACI analyses were conducted on four different MDI formulations with regards to each of the three inlet configurations in quadruplicate. The two hydrofluoroalkane propellants assessed were HFA-134 and HFA-227. All four solution formulations contained 0.3% (w/w) beclomethasone dipropionate (BDP), two of which contained 8% (w/w) ethanol (one each with HFA-134a and HFA-227) and two contained 20% (w/w) ethanol (one each with HFA-134a and HFA-227). All experiments were conducted at a flow rate of 28.3L/min using an actuator with an orifice diameter of 0.29mm and a 50μL metered-valve. After each ACI test, the drug collected on each stage of the impactor was rinsed with known volumes of diluent and quantified by high performance liquid chromatography (HPLC). The MMAD was determined by using DistFit to lognormally fit the ACI data. The resiprable fraction was calculated as the mass of the drug collected on stages 3 through filter of the ACI divided by the total mass of the drug aerosolized. The two-sided student's t-test was the statistical test utilized, with an a priori alpha-value of 0.05. Main Results: The USP and biological throats had significantly lower percent respirable drug compared to the globe regardless of concentration of ethanol or propellant (p<0.05). The MMADs were significantly lower for configurations with the USP and biological throats as compared to the globe (p<0.05). The only formulation with a significant percent respirable drug difference between the USP and biological throats regarding was the 20% ethanol/HFA-227 formulation (20.9+/-0.15 and 16.8+/-1.3 respectively, p=0.005), with the USP throat having the significantly greater percent respirable drug. The USP throat had significantly larger MMADs compared to the biological throat regardless of formulation (p<0.05). For both propellants, the 8% ethanol formulation had significantly greater percent respirable drug compared to the 20% formulation for all three inlets (p<0.05). The 20% ethanol formulations had significantly higher MMADs compared to the 8% ethanol formulations in both the USP throat and globe and with both propellants (p<0.05). Only the 20% ethanol formulations demonstrated a significant difference when varying propellant while keeping all else constant, with the HFA-134a formulations having higher percent respirable drug with all inlets as compared to HFA-227 (p<0.05). When propellant used was varied with all else kept constant, the HFA-227 formulations had significantly higher MMADs compared to the HFA-134a formulations (p<0.05). Conclusion: It was found that significant differences in percent respirable drug and particle size (MMAD) resulting from varying inlet configurations was a function of formulation parameters, most notably, ethanol concentration. The differences may be attributed to factors that increased the time necessary for the evaporation of atomized particles prior to deposition in the impactor, the initial atomized droplet diameter, and/or the likelihood of particle impaction with regards to the mouth-throat inlet utilized. Further assessment is needed to evaluate the correlation of this data with in vivo analyses.
8

On nonlinear free surface potential flow by a Bubnov-Galerkin formulation in space and a semi-lagrangian semi-implicit scheme in time

Allievi, Alejandro January 1993 (has links)
The potential flow initial-boundary value problem describing fluid-structure interaction with fully nonlinear free surface boundary conditions has been studied using a mixed Lagrangian-Eulerian formulation. The boundary-value problem has been solved in the physical domain by means of a Bubnov-Galerkin formulation of the Laplace equation. The initialvalue problem related to the behavior of some of the moving boundaries has been discretized using various numerical techniques. Among these is a series of predictor-corrector methods. These methodologies proved to require considerable numerical smoothing to maintain stability of the numerical scheme. In turn, dissipation led to inaccuracies in the solution of the problem. In order to avoid this negative effect, a semi-implicit semi-Lagrangian two-time level iterative scheme that is almost free from smoothing has been developed. A Bubnov-Galerkin formulation of an elliptic system for the generation of boundary fitted curvilinear coordinates has been used. When solved iteratively, this method provides orthogonal meshes of very good characteristics for both symmetric and non-symmetric domains. Previous publications concluded that the present system was inadequate for non-symmetric regions leading to lack of convergence in the iterative process. Solutions described in this work show that this limitation has been overcome. Fluid responses to periodic excitation of surface-piercing and submerged bodies have been calculated. Both linear and nonlinear cases show agreement with published results. Very low total energy/work error has been obtained which demonstrates accuracy, good stability and convergence characteristics of the numerical scheme. The impulsive response of tanks of various shapes has also been simulated. Resulting natural frequencies show good agreement with available data. A slender body representation of the flow around a hull advancing with forward speed in otherwise calm water has also been simulated. Numerical calculations of a number of quantities of engineering interest are presented for different length Froude numbers. Results compare favorably with experimental data. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate
9

The design of active circulators

Lamb, Larry Lee January 1980 (has links)
No description available.
10

Formulation de pâtes céramiques innovantes contenant des composés organiques biosourcés / Eco-friendly alumina suspensions for tape-casting process

Marie, Jeremy 10 December 2018 (has links)
L’objectif de ce travail est de réaliser des suspensions aqueuses d’alumine, écoresponsables, dont le comportement rhéologique est adapté à la mise en forme par coulage en bande. En effet, les suspensions utilisées dans le procédé de coulage en bande sont classiquement composées d’une poudre céramique, d’un solvant, d’un dispersant, d’un liant et d’un plastifiant. Ces additifs sont généralement des polymères issus de la pétrochimie susceptibles de présenter des risques pour la santé de l’opérateur et/ou pour l’environnement (en particulier avec les solvants organiques). Ces travaux visent donc de substituer tous les additifs venant de la pétrochimie par des additifs écoresponsables, ne présentant aucun risque pour la santé de l’opérateur et pour l’environnement. Les travaux menés dans le cadre de cette thèse ont alors permis d’identifier des polymères naturels extraits de plantes comme des candidats prometteurs pour le remplacement des additifs organiques classiques. Puis, l’étude des interactions entre ces bio-polymères et l’alumine a mené au développement d’un protocole spécifique adapté à la formulation de suspensions d’alumine à base de ces bio-molécules. Ainsi, à l’aide de ce protocole, des suspensions aqueuses ont été réalisées avec ces additifs écoresponsables qui ont abouti à la réalisation de bandes crues facilement manipulables et ne présentant ni craquelures, ni bulles. Enfin, les densités après frittage obtenues sont proches des valeurs rencontrées dans la littérature / The aim of this work is focused on the elaboration of new alumina suspensions with biopolymer additives and rheological properties adapted to the tape casting process. The suspensions used in the tape casting process are basically composed of a ceramic powder, a solvent, a dispersant, a binder and a plasticizer. These additives are usually polymers coming from the petrochemical sector which show risks for the operator health or the environment (in particular with organic solvents). Thus, natural polymers extracted from plants were identified as promising candidates in order to substitute the classical organic additives. Then, the study of the interactions between different organic additives with alumina led to a specific protocol for the formulation of aqueous alumina suspensions with these bio-polymers. Then, mechanical properties of the green and sintered tapes were evaluated in relation with the nature of bio-polymer additives. The obtained densities are close to the values reported in the litterature

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