Sensitivity testing

In some instances, the energy input is strongly absorbed by the mixture in other systems, there is little transfer of energy to the composition. Hence, there is no alternative but to test each new composition for its sensitivity by running the whole scan of standard sensitivity tests friction, impact, spark, and thermal, with shock sensitivity often measured as well. 

To achieve ignition in systems that contain molecular fuels such as a sugar, oxygen-rich anions like chlorate or nitrate, or both, it is necessary for some chemical bonds in the mixture to absorb a sufficient quantity of the incident energy for bond 

how do we use sensitivity data We use it by comparing the sensitivity of a new composition to other compositions with a history of manufacturing and handling safety. If the sensitivity results for a new material are comparable to those for a material with a history of accidents, special caution is called for. This approach only works when the sensitivity data are obtained using the same type of test apparatus, preferably the identical device with the tests run by the same test operator. Even here, however, sensitivity of a particular composition to each type of energy input can vary from day to day and batch to batch should changes in particle size, moisture content, homogeneity, sample age, and chemical purities occur. 

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This paper describes the result obtained in a study of AFCEN (French Society for Design and Construction Rules for Nuclear Island Components) in order to characterize dye penetrant product family, based on experimental test methods of french standards NFA 09.520 and NFA 09.521. In particular, sensitivity tests have been carried out on artificial defects, and correlated with tests on real defects. Some tests on penetrant washability have also been performed. The results obtained with these three series of tests show that the choiee of a dye penetrant product family is not without influency on results obtained, and that is not so simple to make the good choice which could, in certain cases, be the less bad compromise. 

This study, carried out with coloured and fluorescent penetrants, is based on french standards NFA 09.520 and NFA 09.521. Some practical tests (removing of penetrant and over-washing) and sensitivity tests have been done for eaeh range of produet. 

The sensitivity tests are carried out on artificial defects (nickel-chromium specimens of NFA 09.520,see figure 3 of annex 1) and natural defects (one part in "light" alloy, one part in stellite grade 1 containing micropores, 2 specimens of fracture mechanical type CT20 in Z2 CN 12.10 (NFA 03.180). 

The tables 5 and 6 give the results of sensitivity tests obtained on the nickel-chromium specimens of 20 and 10 pm for the fluorescent range products, and of 50 and 30 pm for the colored range of products. 

The sensitivity test on nickel-chromium test blocks show that products which give bad results to over washing tests generally do not give good results to sensitivity tests. 

In co-operation with LM Glasfiber, a complete section of a rotor blade was produced with a number of well defined defects in order to perform an initial sensitivity test by means of ultrasound, vibrations techniques and real-time radiography. Based on the results of this initial test it was found that automated ultrasonic inspection was the best suited teclmique. In co-... 

The following several sections deal with various theories or models for adsorption. It turns out that not only is the adsorption isotherm the most convenient form in which to obtain and plot experimental data, but it is also the form in which theoretical treatments are most easily developed. One of the first demands of a theory for adsorption then, is that it give an experimentally correct adsorption isotherm. Later, it is shown that this test is insufficient and that a more sensitive test of the various models requires a consideration of how the energy and entropy of adsorption vary with the amount adsorbed. Nowadays, a further expectation is that the model not violate the molecular picture revealed by surface diffraction, microscopy, and spectroscopy data, see Chapter VIII and Section XVIII-2 Steele [8] discusses this picture with particular reference to physical adsorption. 

All ammonium salts evolve ammonia on heating with alkali. Ammonia may be delected by (a) its smell, (b) its action in turning red litmus blue and (c) the orange-brown colour produced with Nessler s reagent. This is a very sensitive test. 

The oxidation of black lead(II) sulphide to the white sulphate is a very sensitive test if the black sulphide is used as a stain on filter paper. 

Formation of silver mirror or precipitate of silver indicates reducing agent. (This is often a more sensitive test than I (a) above, and some compounds reduce ammoniacal silver nitrate but are without effect on Fehling s solution.) Given by aldehydes and chloral hydrate formates, lactates and tartrates reducing sugars benzoquinone many amines uric acid. 

One of the most sensitive tests of the dependence of chemical reactivity on the size of the reacting molecules is the comparison of the rates of reaction for compounds which are members of a homologous series with different chain lengths. Studies by Flory and others on the rates of esterification and saponification of esters were the first investigations conducted to clarify the dependence of reactivity on molecular size. The rate constants for these reactions are observed to converge quite rapidly to a constant value which is independent of molecular size, after an initial dependence on molecular size for small molecules. The effect is reminiscent of the discussion on the uniqueness of end groups in connection with Example 1.1. In the esterification of carboxylic acids, for example, the rate constants are different for acetic, propionic, and butyric acids, but constant for carboxyUc acids with 4-18 carbon atoms. This observation on nonpolymeric compounds has been generalized to apply to polymerization reactions as well. The latter are subject to several complications which are not involved in the study of simple model compounds, but when these complications are properly considered, the independence of reactivity on molecular size has been repeatedly verified. 

Still assuming terminal control, evaluate r and T2 from these data. Criticize or defend the following proposition The copolymer composition equation does not provide a very sensitive test for the terminal control mechanism. 

R. H. Richardson and co-workers, "Ha2ards Analysis Through Quantitative Interpretation of Sensitivity Testing," in Proceedings of the International... 

G. R. Walker and co-workers. Manual of Sensitivity Tests, The Technical Cooperation Program, TICP Panel 0-2C Canadian Armament Research and Development Establishment, Quebec, Canada, 1966. 

The presence of manganese can be detected by formation of the purple MnO upon oxidation using bismuth or periodate in acidic solution. A very sensitive test is the reaction of and formaldoxime hydrochloride in aqueous alkaline solution, which also leads to the production of a purple MnO ... 

Shock Sensitivity Shock-sensitive materials react exothermically when subjected to a pressure pulse. Materials that do not show an exotherm on a DSC or DTA are presumed not to be shock sensitive. Testing methods include ... 

With liquids, the refractive index at a specified temperature and wavelength is a sensitive test of purity. Note however that this is sensitive to dissolved gases such as O2, N2 or CO2. Under favourable conditions, freezing curve studies are sensitive to impurity levels of as little as 0.(X)1 moles per cent. Analogous fusion curves or heat capacity measurements can be up to ten times as sensitive as this. With these exceptions, most of the above methods are rather insensitive, especially if the impurities and the substances in which they occur are chemically similar. In some cases, even an impurity comprising many parts per million of a sample may escape detection. 

It should be noted that the dispersion model for radioactive material developed in WASH-1400 for reactor sites as a class cannot be applied to individual sites without significant refinement and sensitivity tests,... 

Siegel, A.I. et al., Maintenance Personnel Performance Simulation (MAPPS) Model Description of Model Content, Structure and Sensitivity Testing, 1984. 

The molecular uniformity of constituting components of a nb/lcb glucan fraction of potato starch was investigated with Sepharose CL 2B (Fig. 16.16) as well as with Sephacryl S-1000 (Fig. 16.17). Therefore, each of the subsequently eluted 3-ml fractions was analyzed on their potential to form inclusion complexes with iodine, a sensitive test for the presence of nb/lcb glucans. Results are shown in Fig. 16.17 in terms of branching index, the ratio of extinction of pure iodine solution and of nb/lcb glucan/iodine complex the higher the index, the more pronounced the nb/lcb characteristics. 

The elements are obtainable in a state of very high purity but some of their physical properties are nonetheless variable because of their dependence on mechanical history. Their colours (Cu reddish, Ag white and Au yellow) and sheen are so characteristic that the names of the metals are used to describe them. Gold can also be obtained in red, blue and violet colloidal forms by the addition of vtirious reducing agents to very dilute aqueous solutions of gold(III) chloride. A remarkably stable example is the Purple of Cassius , obtained by using SnCla as reductant, which not only provides a sensitive test for Au but is also used to colour glass and ceramics. Colloidal silver and copper are also obtainable but are less stable. 

Eor ionic liquids that do not mix completely with water (and which display sufficient hydrolysis stability), there is an easy test for acidic impurities. The ionic liquid is added to water and a pEf test of the aqueous phase is carried out. If the aqueous phase is acidic, the ionic liquid should be washed with water to the point where the washing water becomes neutral. Eor ionic liquids that mix completely with water we recommend a standardized, highly proton-sensitive test reaction to check for protic impurities. 

The complexity of the plant and the type and number of sensitivity tests to be carried out will determine whether a formal model or a simple calculation is needed. 

We have seen in Experiment 8 that silver chloride has low solubility in water. This is also true for silver bromide and silver iodide. In fact, these low solubilities provide a sensitive test for the presence of chloride ions, bromide ions, and iodide ions in aqueous solutions. If silver nitrate... 

What about the state of equilibrium for the reaction represented by equation (11)1 Let us place a strip of metallic copper in a zinc sulfate solution. No visible reaction occurs and attempts to detect the presence of cupric ion by adding H2S to produce the black color of cupric sulfide, CuS, fail. Cupric sulfide has such low solubility that this is an extremely sensitive test, yet the amount of Cu+2 formed cannot be detected. Apparently the state of equilibrium for the reaction (11) greatly favors the products over the reactants. 

Pendulum, Friction, Apparatus. See under Friction Sensitivity Tests in Vol 6, F204-L to F206-L... 

Projectile Sensitivity. Andreev Belyaev (Ref 32, p 473) showed that PA packed in wooden crates detonates if impacted by a 4g projectile moving at greater than 40Qm/sec. In the rifle bullet sensitivity test 0% explosions, 60% partials and 40% combustions were observed for PA (Ref 48)... 

Sensitivity testing of primers (Refs 3 IS) is conducted with the primers inserted into the specified cartridge case in which they are to be used. The primer is inserted into the primer pocket of the cartridge case so that.the surface of the primer cup, when measured from the center of the primer, is within the tolerance specified on the applicable cartridge drawing. The test is performed in accordance with the complete run-down method described in TECP 700-700, Volume III. AMCR 717-505, Volumes 3 and 5 or AMSMU-P-715-501 FA1, as applicable... 

There have been few discussions of the specific problems inherent in the application of methods of curve matching to solid state reactions. It is probable that a degree of subjectivity frequently enters many decisions concerning identification of a best fit . It is not known, for example, (i) the accuracy with which data must be measured to enable a clear distinction to be made between obedience to alternative rate equations, (ii) the range of a within which results provide the most sensitive tests of possible equations, (iii) the form of test, i.e. f(a)—time, reduced time, etc. plots, which is most appropriate for confirmation of probable kinetic obediences and (iv) the minimum time intervals at which measurements must be made for use in kinetic analyses, the number of (a, t) values required. It is also important to know the influence of experimental errors in oto, t0, particle size distributions, temperature variations, etc., on kinetic analyses and distinguishability. A critical survey of quantitative aspects of curve fitting, concerned particularly with the reactions of solids, has not yet been provided [490]. 

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