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First test

This new probe design associated with the preprocessings presented in this paper allows efficient flaw detection. The first tests with silicium coils probe give similar results and give great hope in future tomographic reconstruction. [Pg.364]

The water quality (air content) and the water flow influenced the measurements using one channel. Therefore the four channel system was first tested in the laboratory with a stationary tube. The best results were obtained using tap water and a well controlled flow in a water-filled chamber. A great difference in the concentration of air in the different grades of water was obvious, and the tap water was superior to soft water during these measurements. [Pg.900]

Also present in the first test tube is a synthetic analog of ATP in which both the 2 and 3 hydroxyl groups have been replaced by hydrogens This compound is called 2 3 dideoxyadenosme triphosphate (ddATP) Similarly ddTTP is added to the second tube ddGTP to the third and ddCTP to the fourth Each tube also contains a primer The primer is a short section of the complementary DNA strand which has been labeled with a radioactive isotope of phosphorus ( P) When the electrophoresis gel is examined at the end of the experiment the positions of the DNAs formed by chain extension of the primer are located by a technique called autoradiography which detects the particles emitted by the P isotope... [Pg.1181]

The KDF filter was first tested in prototype on a coal mine in northern Germany. It was installed in parallel with existing vacuum filters and it produced filter cakes consistendy lower in moisture content by 5 to 7% than the vacuum filters. Two production models have been installed and operated on a coal mine in Belgium. The filter is controlled by a specially developed computer system this consists of two computers, one monitoring the function of the filter and all of the detection devices installed, and the other controlling the filtration process. The system allows optimization of the performance, automatic start-up or shut-down, and can be integrated into the control system of the whole coal washing plant. [Pg.406]

The therapeutically active dmg can be extracted from plant or animal tissue, or be a product of fermentation (qv), as in the case of antibiotics. Frequentiy, it is synthesized and designed to correlate stmcture with therapeutic activity. Pharmacologic activity is first tested on laboratory animals. When the results ate encouraging, physical and chemical properties are determined in the so-called preformulation stage, and analytical procedures are developed for quahty control (see Qualityassurance/qualitycontrol). [Pg.225]

Because of the simplicity of the first test method, most of the comparisons are made usiag this technique. The effects of the aging process are usually measured on tensile properties such as tensile strength, elongation, and stress (modulus) at 300% elongation (42). [Pg.247]

For a first test of the reactor and all associated service installations it is recommended that experiments for methanol synthesis should be carried out even if this reaction is not especially interesting for the first real project. The reason for this recommendation is that detailed experimental results were published on methanol synthesis (Berty et al, 1982) made on a readily available catalyst. This gives a good basis of comparison for testing a new system. Other reactions that have been studied in detail and for which the performance of a catalyst is well known can also be used for test reactions. [Pg.83]

The word lest is quite broad in its definition, and many of the inspection steps in the course of the compressor manufacturing cycle can appropriately be called tests. An example would be the material tests. The API mechanical equipment standards, however, attempt to narrow the test definition. This chapter will discuss testing within these narrowed definitions. The first test defined in most API mechanical equipment standards is the hydrostatic test, and it will, therefore, be the first test covered in the chapter. [Pg.403]

The first test to be considered is not an operational test, but the tn i major assembly proof test. [Pg.405]

The hydrostatic testing is the first test used on the lube system. The system is tested while assembled or partially assembled, based on the particular system. A test pressure of VA times the maximum allowable working pressure, a minimum of 20 psi for the oil side, is used for the test. For the oil-wetted parts, the test fluid should be light oil, which is normally the recommended lubricant for the compressor train. The test period is the length of time needed to inspect for leaks, or a minimum ol thirty minutes. Acceptance is based on the lack of leaks as visually observed or the lack of a drop in the test pressure. [Pg.415]

Contains Nitrogen.—First test the original solid ni liquid by heating in a hard-glass tube with soda-lime (p. 2), and notice if the smell is that of ammonia (ammonia salt, amide or cyanide), an amine (amine or amino-acid) or a pyridine base (alkaloid). [Pg.330]

The same data, including those involving substituents in the 3-position, which are in a vicinal relation to the side-chain, have been treated by Guerillot using cr-values theoretically calculated for this reaction series and give an excellent correlation. This represents the first test of his theoretical treatment of the Hammett equation. [Pg.256]

The first experiments with the thermal electric engine were conducted in Russia in 1929 by its inventor, Valentin P. Glushko, who later became a world-famous authority in rocket propulsion. For more than forty years, the United States and Russia have devoted many resources to research and development of various kinds of EREs. First tested in space by the Russians in 1964, these engines have found some limited applications in modern space technology. For more than two decades Russian weather and communication satellites have regularly used electric rocket engines for orbital stabilization. The first spacecraft to employ ERE for main propulsion was the American asteroid exploration probe Deep Space 1, launched in 1998. The performance of... [Pg.1076]

Water from towns main supplies is usually suitable for the preparation of water-based cutting fluids. That from factory bore holes is also generally suitable, although occasionally it contains excessive amounts of corrosive salts. Water from rivers, canals and ponds usually contains undesirable contaminants, and should be tested before use. A good first test is to mix a small quantity of emulsion and allow it to stand for 24 hours in this time, no more than a trace of the oil should separate. If serious separation occurs, the water should be analyzed to indicate the sort of remedial treatment required. [Pg.873]

The power of the new spectrometer to reveal configurations of difficult cyclitols or sugars was first tested with mt/o-inositol (2), using deuterium oxide as solvent. At 60 or 100 MHz. the one equatorial and five axial protons appear to have different chemical shifts as shown by Lemieux in 1956 with a 40 MHz. instrument (14,15). However, since the five-proton axial signal could not be resolved, one could probably not have assigned the configuration 2 (which was already known from laborious chemical correlations extending over many years.)... [Pg.57]

For metabolite work, first test the separation on the precursor drug or chemical. [Pg.247]

Self-Tests occur in pairs throughout the book. They enable students to test their understanding of the material covered in the preceding section or worked Example. An answer to the first test gives immediate feedback the answer to the second is in the back of the book, along with the setup for the calculation. [Pg.14]

Xu et al. (2000) investigated de-ionized water flow in micro-channels with hy-draulie diameter ranging from 30 to 344 pm at Reynolds numbers ranging from 20 to 4,000. Two test modules were used. The first test module consisted of a cover and an aluminum plate, into which a micro-channel, inlet and outlet sumps were machined. A Plexiglas plate was used to cover the channel. The second module was fabricated from a silicon wafer, and a 5 mm thick Pyrex glass was utilized to... [Pg.108]

When the antitumor activity of cisplatin was discovered, several research groups started to investigate the possible therapeutic applications of other metal-based, often organometallic, compounds. The organotin(lV) compounds that were first tested were those that were available or easily synthesized, like tri- or diorganotin(rV) halides. [Pg.423]

Pathological Behavior. An important use of residence time measurements is to diagnose flow problems. As indicated previously, the first test is whether or not t... [Pg.552]

These different catalysts were first tested in the desymmetrization of the achiral triene 63 (Scheme 40). The best enantioselectivities (up to 39%) were obtained with complexes 60b and 61c-d bearing carbene ligands derived from 1,2-diphenyl-1,2-diaminoethane (R = Ph). ligands derived from 1,2-diaminocyclohexane gave poor enantioselectivities (< 9% ee). Replacement of the mesityl group in complex 60b by o-methyl- or o-isopropylphenyl groups (complexes 61c-d) slightly increases the enantioselectivity (from 13... [Pg.216]

These catalysts were first tested as resin-bound derivatives via HTS, first with metals and then without. Three libraries of chiral molecules, based on three different enantiomerically pure diamines, bulky salicylidene moities and optically active ii-amino acids were used for structure optimisation (Scheme 37 TBSCN = fBuMe2SiCN) [152]. [Pg.256]

The reaction was first tested with these substances as ligands but the organic molecule, in the absence of any added metal ion, proved to be the most enantioselective catalyst (library 1 19% ee vs. less than 13% ee for the best metal catalyst). The effects of selective variations of the amino acid nature and of the salicylidene moiety on the diamine structure were investigated for urea and thiourea derivatives via HTS (library 2 48 urea compounds and... [Pg.256]

A classification decision tree allows one to predict in a sequential way the y value (or corresponding conditional probabilities) that is associated with a particular x vector of values. At the top node of the tree (A in Fig. 3), a first test is performed, based on the value assumed by a particular decision variable (jCj). Depending on the outcome of this test, vector X is sent to one of the branches emanating from node A. A second test follows, being carried out at another node (B), and over the values of the same or a different decision variable (e.g., JCg). This procedure is... [Pg.113]

It is likely that transcriptional regulation of Na /H exchanger gene expression is responsible for some of these observations, a possibility that could be first tested by examining the structure and function of the gene promoter. [Pg.268]

Following the arguments given above, micro mixers are valuable tools for bench-scale continuous processing to fill the recycle loop. For first tests on feasibility, the total volume of the recycle loop has to be kept small, demanding also for small-scale processing units. Conventional devices would probably suffer here from too large internal volumes. [Pg.483]


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See also in sourсe #XX -- [ Pg.204 ]




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