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Reference secondary

In a current developing standards document being considered for the international sterilisation community, under a section on Dosimeters , it is specified that each batch of dosimeters to be used must be properly calibrated. This entails either (1) irradiation of a user s dosimeter in a standards or accredited reference (secondary) laboratory, and subsequent appropriate evaluation by the user, (2) irradiation in a suitably designed irradiation geometry in the user s laboratory along with dosimeters issued by a standards or reference laboratory, or (3) use of a radiation field where the calibration is traceable to a standards laboratory, according to an acceptable accreditation procedure. [Pg.297]

As we will see later, iRu drop is also very small when working with microelectrodes and, in fact, is not greatly affected by the distance between the reference/secondary electrode electrode and the working electrode. This therefore rarely presents a problem with microelectrodes. [Pg.158]

The reference, secondary hot gas duct (900 °C) was designed as a duct with an inner flow guidance liner, an fibre-type insulation wrapped on the liner (AI2O3 and Si02) and an outer uncooled pressure tube. [Pg.238]

Insulation failure references secondary of system to earth - shock protection removed... [Pg.40]

The reference secondary mean droplet size (jC5o,3j ozzie) for higher liquid flow rate condition was certainly smaller due to the more efficient pre-reductimi of the droplet in the liquid-cap nozzle flow. [Pg.978]

Nucleus Primary reference molecule Method Reference Secondary reference liquid Method Reference... [Pg.56]

If the spectrum of the outside surface is obtained by ATR/MIR, however, we obtain the spectrum shown in Figure 10.9, and that is not a spectrum of cellophane but rather of nitrocellulose. There are no bands in this spectrum corresponding to cellophane at all. The spectrum, not shown, from the inside of the same overwrap was also obtained by ATR/MIR, and this latter spectrum very closely matched that of a reference secondary amide, a commonly used vehicle for printing inks. It also appears that dioctylphthalate (or perhaps camphor) was used as a plasticizer on both the inside and outside surfaces. [Pg.273]

Secondary ion mass spectrometry (SIMS) is by far the most sensitive surface teclmique, but also the most difficult one to quantify. SIMS is very popular in materials research for making concentration depth profiles and chemical maps of the surface. For a more extensive treatment of SIMS the reader is referred to [3] and [14. 15 and 16]. The principle of SIMS is conceptually simple When a surface is exposed to a beam of ions... [Pg.1860]

At larger particle separation, a second minimum may occur in tire potential energy. In many cases, tliis minimum is too shallow to be of much significance. For larger particles, however, tire minimum may become of order kT. Aggregation in tliis minimum is referred to as secondary minimum flocculation. [Pg.2682]

Some reference to the use of nitrous acid merits mention here. Primary aromatic amines yield diazonium compounds, which may be coupled with phenols to yield highly-coloured azo dyes (see Section IV,100,(iii)). Secondary aromatic amines afford nitroso compounds, which give Liebermann a nitroso reaction Section IV,100,(v). Tertiary aromatic amines, of the type of dimethylaniline, yield p-nitroso derivatives see Section IV,100,(vii). ... [Pg.1073]

For the secondary pH reference standards, the buffer value is 0.070 for potassium tetroxalate and 0.09 for calcium hydroxide. [Pg.933]

Secondary reference points to extend the scale (IPTS-68) Freezing point of platinum 2042 1769... [Pg.1215]

A big step forward came with the discovery that bombardment of a liquid target surface by abeam of fast atoms caused continuous desorption of ions that were characteristic of the liquid. Where this liquid consisted of a sample substance dissolved in a solvent of low volatility (a matrix), both positive and negative molecular or quasi-molecular ions characteristic of the sample were produced. The process quickly became known by the acronym FAB (fast-atom bombardment) and for its then-fabulous results on substances that had hitherto proved intractable. Later, it was found that a primary incident beam of fast ions could be used instead, and a more generally descriptive term, LSIMS (liquid secondary ion mass spectrometry) has come into use. However, note that purists still regard and refer to both FAB and LSIMS as simply facets of the original SIMS. In practice, any of the acronyms can be used, but FAB and LSIMS are more descriptive when referring to the primary atom or ion beam. [Pg.17]

Confusingly, FAB is sometimes called secondary ion mass spectrometry (SIMS), the secondary referring to the nature of the process (primary bombardment, secondary emission), but see next item. [Pg.386]

The term liquid secondary ion mass spectrometry (LSIMS) is sometimes used synonymously with FAB and is preferred by some as being more descriptive, since FAB could apply to bombardment of solid or liquid surfaces and does not indicate the types of secondaries investigated. In practice, little confusion is likely to result from using either term. Strictly, LSIMS can refer to the use of fast ions (FIB). [Pg.394]

Secondary structure refers to the shape of the molecule as a whole, particularly to those aspects of structure which are stabilized by intramolecular hydrogen bonds. [Pg.19]

Air pollution can be considered to have three components sources, transport and transformations in the atmosphere, and receptors. The source emits airborne substances that, when released, are transported through the atmosphere. Some of the substances interact with sunlight or chemical species in the atmosphere and are transformed. Pollutants that are emitted directiy to the atmosphere are called primary pollutants pollutants that are formed in the atmosphere as a result of transformations are called secondary pollutants. The reactants that undergo transformation are referred to as precursors. An example of a secondary pollutant is O, and its precursors are NMHC and nitrogen oxides, NO, a combination of nitric oxide [10102-43-9] NO, and NO2. The receptor is the person, animal, plant, material, or ecosystem affected by the emissions. [Pg.366]

The autoclave is not the only component of an LDPE plant which may be exposed to a decomposition. Local hot spots in a secondary compressor may initiate a decomposition reaction consequendy it is necessary to protect these units from serious overpressure by pressure relieving devices and to release the products of the decomposition reactions safely. The problem of the aerial decomposition referred to eadier has been largely overcome by rapidly quenching the decomposition products as they enter the vent stack. [Pg.98]

Hypercompressors. In an LDPE plant a primary compressor, usually of two stages, is used to raise the pressure of ethylene to about 25—30 MPa and a secondary compressor, often referred to as a hypetcomptessot, is used to increase it to 150—315 MPa (22,000—45,700 psi). The thermodynamic properties of ethylene ate such that the secondary compressor requires only two stages and this results in a large pressure difference between the second stage suction and discharge pressures. [Pg.100]

Radiation Damage. It has been known for many years that bombardment of a crystal with energetic (keV to MeV) heavy ions produces regions of lattice disorder. An implanted ion entering a soHd with an initial kinetic energy of 100 keV comes to rest in the time scale of about 10 due to both electronic and nuclear coUisions. As an ion slows down and comes to rest in a crystal, it makes a number of coUisions with the lattice atoms. In these coUisions, sufficient energy may be transferred from the ion to displace an atom from its lattice site. Lattice atoms which are displaced by an incident ion are caUed primary knock-on atoms (PKA). A PKA can in turn displace other atoms, secondary knock-ons, etc. This process creates a cascade of atomic coUisions and is coUectively referred to as the coUision, or displacement, cascade. The disorder can be directiy observed by techniques sensitive to lattice stmcture, such as electron-transmission microscopy, MeV-particle channeling, and electron diffraction. [Pg.394]

The endpoint value for any changing concentration, such as [A ], sometimes referred to as the infinity point, is extremely important in the data analysis, particularly when the order of the reaction is not certain. The obvious way to determine it, ie, by allowing the reaction to proceed for a long time, is not always rehable. It is possible for secondary reactions to interfere. It may sometimes be better to calculate the endpoint from a knowledge of the... [Pg.508]

Other materials that are often referred to as secondary plasticizers iaclude materials such as epoxidized soybean oil (ESBO) and epoxidized linseed oil (ELO) and similar materials. These can act as lubricants but also as secondary stabilizers to PVC due to thein epoxy content which can remove HCl from the degrading polymer. [Pg.123]

Amines are derivatives of ammonia in which one or more of the hydrogens is replaced with an alkyl, aryl, cycloalkyl, or heterocycHc group. When more than one hydrogen has been replaced, the substituents can either be the same or different. Amines are classified as primary, secondary, or tertiary depending on the number of hydrogens which have been replaced. It is important to note that the designations primary, secondary, and tertiary refer only to the number of substituents and not to the nature of the substituents as in some classes of compounds. [Pg.257]


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See also in sourсe #XX -- [ Pg.8 ]




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