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Process laboratory processing

The rate of radioactive transformations cannot be altered by changing the conditions which are available in the laboratory. The process is a spontaneous one. [Pg.339]

Separation of families by merely increasing the resolution evidently can not be used when the two chemical families have the same molecular formula. This is particularly true for naphthenes and olefins of the formula, C H2 , which also happen to have very similar fragmentation patterns. Resolution of these two molecular types is one of the problems not yet solved by mass spectrometry, despite the efforts of numerous laboratories motivated by the refiner s major interest in being able to make the distinction. Olefins are in fact abundantly present in the products from conversion processes. [Pg.50]

While the long chain hydrocarbons (above 18 carbon atoms) may exist in solution at reservoir temperature and pressure, they can solidify at the lower temperatures and pressures experienced in surface facilities, or even in the tubing. The fraction of the longer chain hydrocarbons in the crude oil are therefore of particular interest to process engineers, who will typically require a detailed laboratory analysis of the crude oil oomposition, extending to the measurement of the fraction of molecules as long as C3Q. [Pg.92]

At present time is the acoustic emission laboratory of the Institute of Design already equipped with modem analysers processing 4 and 16 AE sensors (each enables to sense up to 256 levels). All analysers have at disposal powerful computing technique and corresponding software. [Pg.62]

The first step involved massive testing at ANDREX laboratory to determine the optimal detection process. Two imaging methods were discussed, one using a linear detector array, the other using a high resolution image intensifier. [Pg.587]

The weld depths penetration for gold-nickel alloy and tantalum cylinders have been well controlled by an entirely contactless ultrasound method. Nevertheless, the development of signal and image processing will allow to increase the resolution of the ultrasonic images. Moreover, in order to be able to size quite well the lacks of weld penetration, the simulation of the interaction beam-defect is presently developed in our laboratory. [Pg.699]

For several years, the French Atomic Energy Commission (CEA) has developed modelling tools for ultrasonic NDT configurations. Implemented within the CIVA software for multiple technique NDT data acquisition and processing [1,2], these models are not only devoted to laboratory uses but also dedicated to ultrasonic operators without special training in simulation techniques. This approach has led us to develop approximate models carrying out the compromise between as accurate as possible quantitative predictions and simplicity, speed and intensive use in an industrial context. [Pg.735]

The second approach - creation of systems for non-destructive testing quality assurance in compliance with ISO standards 9000 series - considers the quality system as an assembly of organisational strueture, procedures, processes and resources necessary for overall quality management at the laboratory. This approach requires methodieal development. [Pg.956]

Checking is performed in accredited laboratories on procedures developed in compliance with stated requirements and approved in the process of testing implementation on CTB 8001-93 or metrological attestation on CTB 8004-93. [Pg.964]

If the spreading is into a limited surface area, as in a laboratory experiment, the film front rather quickly reaches the boundaries of the trough. The film pressure at this stage is low, and the now essentially uniform film more slowly increases in v to the final equilibrium value. The rate of this second-stage process is mainly determined by the rate of release of material from the source, for example a crystal, and the surface concentration F [46]. Franses and co-workers [47] found that the rate of dissolution of hexadecanol particles sprinkled at the water surface controlled the increase in surface pressure here the slight solubility of hexadecanol in the bulk plays a role. [Pg.111]

Ferguson E E, Fehsenfeld F C, Dunkin D B, Schmeltekopf A L and Schiff FI I 1964 Laboratory studies of helium ion loss processes of interest in the ionosphere Planet Space Scl. 12 1169-71... [Pg.825]

The selection of the operating principle and the design of the calorimeter depends upon the nature of the process to be studied and on the experimental procedures required. Flowever, the type of calorimeter necessary to study a particular process is not unique and can depend upon subjective factors such as teclmical restrictions, resources, traditions of the laboratory and the inclinations of the researcher. [Pg.1903]

The full dynamical treatment of electrons and nuclei together in a laboratory system of coordinates is computationally intensive and difficult. However, the availability of multiprocessor computers and detailed attention to the development of efficient software, such as ENDyne, which can be maintained and debugged continually when new features are added, make END a viable alternative among methods for the study of molecular processes. Eurthemiore, when the application of END is compared to the total effort of accurate determination of relevant potential energy surfaces and nonadiabatic coupling terms, faithful analytical fitting and interpolation of the common pointwise representation of surfaces and coupling terms, and the solution of the coupled dynamical equations in a suitable internal coordinates, the computational effort of END is competitive. [Pg.233]

Carbon dioxide is used in the manufacture of sodium carbonate by the ammonia-soda process, urea, salicyclic acid (for aspirin), fire extinguishers and aerated water. Lesser amounts are used to transfer heat generated by an atomic reactor to water and so produce steam and electric power, whilst solid carbon dioxide is used as a refrigerant, a mixture of solid carbon dioxide and alcohol providing a good low-temperature bath (195 K) in which reactions can be carried out in the laboratory. [Pg.182]

Fluorine cannot be prepared directly by chemical methods. It is prepared in the laboratory and on an industrial scale by electrolysis. Two methods are employed (a) using fused potassium hydrogen-fluoride, KHFj, ill a cell heated electrically to 520-570 K or (b) using fused electrolyte, of composition KF HF = 1 2, in a cell at 340-370 K which can be electrically or steam heated. Moissan, who first isolated fluorine in 1886, used a method very similar to (b) and it is this process which is commonly used in the laboratory and on an industrial scale today. There have been many cell designs but the cell is usually made from steel, or a copper-nickel alloy ( Monel metal). Steel or copper cathodes and specially made amorphous carbon anodes (to minimise attack by fluorine) are used. Hydrogen is formed at the cathode and fluorine at the anode, and the hydrogen fluoride content of the fused electrolyte is maintained by passing in... [Pg.316]

In 1986, David Weininger created the SMILES Simplified Molecular Input Line Entry System) notation at the US Environmental Research Laboratory, USEPA, Duluth, MN, for chemical data processing. The chemical structure information is highly compressed and simplified in this notation. The flexible, easy to learn language describes chemical structures as a line notation [20, 21]. The SMILES language has found widespread distribution as a universal chemical nomenclature... [Pg.26]

In chemistry and chemical engineering, expert systems are used for various tasks ranging from laboratory automation or reaction kinetics to the design of syntheses or the simulations of processes [24]. The application of expert systems in chemistry is described in more detail in Chapter IX, Section 2 of the Handbook,... [Pg.480]

It should be emphasised that whereas the interaction of a sodium salt and an acid chloride is a convenient general laboratory method for preparing all classes of anhydrides, acetic anhydride is prepared on a large scale by other and cheaper methods. Industrial processes are based on reactions indicated by the equations ... [Pg.116]

The term distillation is applied to vaporisation and subsequent condensation according to (i) it should also be applied to (ii) since it is really the liquid which is converted into vapour and is first formed by condensation. Strictly speaking, the term sublimation should be applied to changes according to (iii). However, in practice, a substance when heated may first melt and then boil, but on cooling it may pass directly from the vapour to the solid the process is then also called sublimation. Indeed the mode of vaporisation, whether directly from solid to vapour or through the intermediate formation of a liquid, is of secondary importance it is the direct conversion of vapour to solid which is really the outstanding feature of sublimation in the laboratory. [Pg.37]

The theory of the process can best be illustrated by considering the operation, frequently carried out in the laboratory, of extracting an orgaiuc compound from its aqueous solution with an immiscible solvent. We are concerned here with the distribution law or partition law which, states that if to a system of two liquid layers, made up of two immiscible or slightly miscible components, is added a quantity of a third substance soluble in both layers, then the substance distributes itself between the two layers so that the ratio of the concentration in one solvent to the concentration in the second solvent remains constant at constant temperature. It is assumed that the molecular state of the substance is the same in both solvents. If and Cg are the concentrations in the layers A and B, then, at constant temperature ... [Pg.44]

All glassware should be scrupulously clean and, for most purposes, dry before being employed in preparative work in the laboratory. It is well to develop the habit of cleaning all glass apparatus immediately after use the nature of the dirt will, in general, be known at the time, and, furthermore, the cleaning process becomes more difficult if the dirty apparatus is allowed to stand for any considerable period, particularly if volatile solvents have evaporated in the meantime. [Pg.53]

Zemplen helped his students in many ways. I remember an occasion in the difficult postwar period. The production of the famous Hungarian salami, interrupted by the war, was just in the process of being restarted for export. The manufacturer wanted a supportive analysis from the well-known professor. Zemplen asked for a suitable sample of some hundreds of kilograms, on which the whole institute lived for weeks. When it was gone he rightly could offer an opinion that the product was quite satisfactory. After the war, grain alcohol was for a long time the only available and widely used laboratory solvent, and, not unexpectedly, it also found other uses. Later, when it was denatured to prevent human consumption, we devised clever ways for its purification. The lab also manufactured saccharine, which was... [Pg.52]


See other pages where Process laboratory processing is mentioned: [Pg.26]    [Pg.30]    [Pg.167]    [Pg.277]    [Pg.341]    [Pg.114]    [Pg.550]    [Pg.694]    [Pg.1064]    [Pg.76]    [Pg.686]    [Pg.1075]    [Pg.1181]    [Pg.1189]    [Pg.1233]    [Pg.1248]    [Pg.1957]    [Pg.2659]    [Pg.229]    [Pg.63]    [Pg.129]    [Pg.169]    [Pg.586]    [Pg.21]    [Pg.89]    [Pg.527]    [Pg.25]    [Pg.48]    [Pg.143]    [Pg.226]   


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