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The aims

An introductory chapter briefly describing the subject, the aim, the approach and the topics. Students are offered advice on how to select material for study, and encouraged to understand the information rather than learn the factual material. General information on ionization in biochemicals and on nomenclature is given, together with a list of common abbreviations. [Pg.1]

This book has been written primarily for pharmacy undergraduates to provide a modem text to complement lecture courses dealing with pharmacognosy and the use of natural products in medicine. Nevertheless, it should be of value in most other courses where the study of natural products is included, although the examples chosen are predominantly those possessing pharmacological activity. [Pg.1]

Gradually synthetic compounds superseded many of the old plant drugs, though certain plant- [Pg.1]


This rather low recovery factor may be boosted by implementing secondary recovery techniques, particularly water Injection, or gas injection, with the aim of maintaining reservoir pressure and prolonging both plateau and decline periods. The decision to implement these techniques (only one of which would be selected) Is both technical and economic. Technical considerations would be the external supply of gas, and the... [Pg.188]

The aim of defect segmentation is to delimit the detected defect as precise as possible from the background which surrounds the defect (fig. 8). The extracted characteristics of a detected casting defect depend considerable on the threshold value which is used during the defect segmentation. [Pg.14]

The aim is to develop a real-time surveillance method to ensure the safety of tests such as resistance tests and re-testing of pressure vessels, based on measurement carried out using acoustic emission technology. [Pg.54]

The present work was done with the aim to evaluate the efficiency of the acoustic emission method as a diagnostic tool for analysing a carbon plastic composite and its adhesive joints. The samples of the carbon plastic type UKN-5000 were used in the test. Non-defected samples and samples with artificial defects were tested. [Pg.83]

Using the equilibrium equations of the elasticity theory enables one to determine the stress tensor component (Tjj normal to the plane of translumination. The other stress components can be determined using additional measurements or additional information. We assume that there exists a temperature field T, the so-called fictitious temperature, which causes a stress field, equal to the residual stress pattern. In this paper we formulate the boundary-value problem for determining all components of the residual stresses from the results of the translumination of the specimen in a system of parallel planes. Theory of the fictitious temperature has been successfully used in the case of plane strain [2]. The aim of this paper is to show how this method can be applied in the general case. [Pg.132]

In this paper, discontinuities in cylindrical specimens were studied by ultrasonic reflection tomography. The aim was threefold. First, to localize discontinuities from circular C-scan images. Second, to reconstruct quantitative cross-sectional images from circular B-scan profiles (i.e., reflection tomograms). Finally, to obtain three-dimensional information (i.e., discontinuity location, dimension and type) by stacking these reflection tomograms in multiple planes, in the third dimension. [Pg.200]

In order to determine the matrix thresholds, we present an expression of the coefficients dispersion that is related to the flattening of the cloud of the points around the central axis of inertia. The aim is to measure the distance to the G barycentre in block 3. So, we define this measure Square of Mean Distance to the center of Gravity as follow ... [Pg.235]

It is a probe whose the coil support is a small circular sticks with a straiglit section. The aim of our study is to assimilate the resulting magnetic field to a material point, hi order to minimize the lateral field, we have chosen the construction of conical coil where the lateral field at a contact point in respect to a straight configuration is decreased with an exponential factor. The results obtained from the curves are as follow ... [Pg.292]

The Direct Current Potential Drop method (DCPD) has been evaluated for non destructive testing of uniaxially produced Powder Metallurgical (P/M) parts. The aim is to adapt DCPD to be functional as an ndt tool during production of parts. Defects can occur at different stages in the production cycle which means that DCPD has to be performed on components in different states and searching for different defects. [Pg.381]

The aim of this work which enter in a research project on NDT, is to conceive a system of aid for interpretation and taking decisions, on imperfections in metallic fusion welds, we have studied and tested several segmentation techniques based on the two approaches ( contour and regions ). A quantitative analysis will be applied to extract some relatives geometricals parameters. To the sight of these characteristics, a first classification will be possible. [Pg.524]

The basic idea is to extract firstly "sure" contours contour segment extremities are identified by studying the local neighbourhood of each pixel. The aim of closing contours algorithm is to find the best path between two points that are extremities of the gap to fulfil. [Pg.528]

Flence, the aims of the new series of metal-ceramic X-ray tubes for lower applications were ... [Pg.535]

But there are two physical phenomena that were not taken into account in the frame of the theory [1-3], although our last researches demonstrate its principal significance for liquid penetrant testing. The aim of this study is to investigate these phenomena and to determine the restrictions on theory applicability. [Pg.613]

The aim of the work we present in this paper is to optimize the control parameters used in particles magnetic and interpret the obtained results. Experiments are performed on samples of welds or materials containing known defects. The realized and tested defects are grooves situated at different depths with variables dimensions. Other types of defects have been studied (inclusions, lack of penetration, etc.). [Pg.635]

The algorithm contains five minimisation procedures which are performed the same way as in the method " i.e. by minimisation of the RMS between the measured unidirectional distribution and the corresponding theoretical distribution of die z-component of the intensity of the leakage field. The aim of the first minimisation is to find initial approximations of the depth d, of the crack in the left half of its cross-section, die depth d in its right half, its half-width a, and the parameter c. The second minimisation gives approximations of d, and d and better approximations of a and c based on estimation of d,= d, and d,= d,j. Improved approximations of d] and d4 are determined by the third minimisation while fixing new estimations of d dj, dj, and dj. Computed final values dj , d/, a and c , whieh are designated by a subscript c , are provided by the fourth minimisation, based on improved estimations of d, dj, dj, and d . The fifth minimisation computes final values d, , d, dj, d while the already computed dj , d/, a and c are fixed. [Pg.688]

The aim of the experiment was to study the transmission of a signal through the weld and to measure the frequency and phase dependencies of parameters of acoustic signals from the angle of incidence and beam path within the weld volume. One of the shift of the spectral characteristics the signal is shown in Figure 4(a,b). [Pg.732]

OPTIMISE, a joint industry project, supported by EC-ESPRIT funding is such a project, where techniques are identified, optimised and validated for the inspection of bulk carriers, with the aim to increase the inspection scope and thus the safety level, at the same time reducing the time needed for the inspections. [Pg.951]

Attestation of the test procedure is realized with the aim to confirm both the correctness of the choice of method and NDT facilities and fullness of requirements included in the test procedure. Attestation ensures reliability of testing results with required accuracy. [Pg.961]

The Ukrainian Society for Non-Destructive Testing and Technical Diagnostics (US NDT TD) was established at the meeting of the leading experts of the country, on October 28, 1990, The aim of the Society s activity is consolidation of the efforts of scientists and engineers for development of their creative and business activity, information exchange, satisfying the professional interests, development of international contacts on NDT TD. [Pg.967]

Later, US NDT TD set up the National Certification Committee of Ukraine on NDT, which had the aim of organising the personnel certification in keeping with EN 473, rendered assistance to State Standardisation Organisation of Ukraine in setting up the Technical Committee on Standardisation Technical Diagnostics and Non-Destructive Testing (TC-78), the aims of which are in tune with those of lSO/TC-135. [Pg.967]

In recent years, the three-level system of NDT experts certification, which corresponds to the EN 473, is being introduced m Ukraine The unified Rules of NDT Experts Certification will be introduced in the near future. This work is headed by the State Committee of Ukraine on Labour Safety), and with the aim of the most expedient transition to EN 473, the National Certification Committee of Ukraine on NDT was established by the initiative of US NDT TD. The Committee has the tasks of preparing the programs, procedures, questionnaires for carrying out the certification. It is a non-profit organisation which is in charge of the methodological issues of certification m the US NDT TD. [Pg.968]

A development project has been initiated with the aim of providing a radiotracer method that ultimately can be implemented as a routine calibration method for permanently installed multiphase flowmeters. The project is supported by a research grant from the Danish Ministry of Energy. [Pg.1056]

In equilibrium statistical mechanics, one is concerned with the thennodynamic and other macroscopic properties of matter. The aim is to derive these properties from the laws of molecular dynamics and thus create a link between microscopic molecular motion and thennodynamic behaviour. A typical macroscopic system is composed of a large number A of molecules occupying a volume V which is large compared to that occupied by a molecule ... [Pg.383]

Although the field of gas-phase kinetics remains hill of challenges it has reached a certain degree of maturity. Many of the fiindamental concepts of kinetics, in general take a particularly clear and rigorous fonn in gas-phase kinetics. The relation between fiindamental quantum dynamical theory, empirical kinetic treatments, and experimental measurements, for example of combustion processes [72], is most clearly established in gas-phase kmetics. It is the aim of this article to review some of these most basic aspects. Details can be found in the sections on applications as well as in the literature cited. [Pg.794]

The following two sections will focus on epitaxial growth from a surface science perspective with the aim of revealing the fundamentals of tliin-film growth. As will be discussed below, surface science studies of thin-film deposition have contributed greatly to an atomic-level understanding of nucleation and growth. [Pg.928]

In this chapter we shall first outline the basic concepts of the various mechanisms for energy redistribution, followed by a very brief overview of collisional intennoleciilar energy transfer in chemical reaction systems. The main part of this chapter deals with true intramolecular energy transfer in polyatomic molecules, which is a topic of particular current importance. Stress is placed on basic ideas and concepts. It is not the aim of this chapter to review in detail the vast literature on this topic we refer to some of the key reviews and books [U, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, and 32] and the literature cited therein. These cover a variety of aspects of tire topic and fiirther, more detailed references will be given tliroiighoiit this review. We should mention here the energy transfer processes, which are of fiindamental importance but are beyond the scope of this review, such as electronic energy transfer by mechanisms of the Forster type [33, 34] and related processes. [Pg.1046]

The construction of an aberration-corrected TEM proved to be teclmically more demanding the point resolution of a conventional TEM today is of the order of 1-2 A. Therefore, the aim of a corrected TEM must be to increase the resolution beyond the 1 A barrier. This unplies a great number of additional stability problems, which can only be solved by the most modem technologies. The first corrected TEM prototype was presented by Flaider and coworkers [M]- Eigure BE 17.9 shows the unprovement in image quality and interpretability gained from the correction of the spherical aberration in the case of a materials science sample. [Pg.1643]

Ultimately we may want to make direct comparisons with experimental measurements made on specific materials, in which case a good model of molecular interactions is essential. The aim of so-called ab initio molecular dynamics is to reduce the amount of fitting and guesswork in this process to a minimum. On the other hand, we may be interested in phenomena of a rather generic nature, or we may simply want to discriminate between good and bad theories. When it comes to aims of this kind, it is not necessary to have a perfectly realistic molecular model one that contains the essential physics may be quite suitable. [Pg.2241]

The aim of this section is to show how the modulus-phase formulation, which is the keytone of our chapter, leads very directly to the equation of continuity and to the Hamilton-Jacobi equation. These equations have formed the basic building blocks in Bohm s formulation of non-relativistic quantum mechanics [318]. We begin with the nonrelativistic case, for which the simplicity of the derivation has... [Pg.158]

In a mechanistic study, the aim is not to quantitatively reproduce an experiment. As a result it is not necessary to use the methods outlined above. The question here is what drives a reaction in a particular direction, or what would happen if the molecule is driven in different ways. The initial conditions are then at the disposal of the investigator to be chosen in a way to answer the relevant question, using a suitable spread of positions and energies. [Pg.272]

In a diabatic representation, the electronic wave functions are no longer eigenfunctions of the electronic Hamiltonian. The aim is instead that the functions are so chosen that the (nonlocal) non-adiabatic coupling operator matrix, A in Eq. (52), vanishes, and the couplings are represented by (local) potential operators. The nuclear Schrddinger equation is then written... [Pg.279]


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AIM

Aim of the Project and Coordination

Aim of the Report

Aim of the Study

Aim of the Work

Aim of the project

Aims of the Book

Aims of the research project

Biodegradable Polymer-based Nanocomposites Nanostructure Control and Nanocomposite Foaming with the Aim of Producing Nano-cellular Plastics

On the aims of this book

The Aim of a Project

The Aims of Isolating Active Principles

The Computational Aim

The Grand Aim of Automatic Programming

The Rationale and Aims of Pharmacogenetics

The aim and structure of this book

The aims of Chapter

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