Equal certificates

The energy of combustion of benzoic acid determined by standardizing laboratories normally refers to the following certification conditions [21,25,39-43] (1) The benzoic acid sample is burned in a bomb at constant volume, in pure oxygen at an initial pressure of 3.04 MPa (2) the mass of sample burned, expressed in grams, is equal to three times the internal volume of the bomb in dm3 (3) the amount of water inside the bomb, expressed in grams, is also equal to three times the internal volume of the bomb in dm3 (4) the combustion reaction is referred to 298.15 K. If calibrations are not made strictly under the certification conditions, the value of Acm(BA) under the actual bomb conditions should... 

Patent protection under general law usually lasts for up to around 20 years. This creates a difficulty in relation to medicinal products, as it can take some 12 years for the products to undergo research, development, the extensive clinical trials that are required in order to obtain a marketing authorisation and the authorisation process itself. These steps are also extremely expensive. The amount of time that remains during which the patent holder can exploit his patent and recoup his massive investment can be severely curtailed in relation to medicinal products. For this reason, the European Community has provided a form of additional patent-related protection for medicinal products authorised within the European Community, by means of a Supplementary Protection Certificate. A patent holder may apply for a certificate that takes effect at the end of the term of the basic patent, for a period equal to the period that elapsed between the date on which the application for the basic patent was lodged and the date of the first authorisation to place a product derived from the patent on the market in the Community, reduced by a period of 5 years. The maximum duration of the certificate is 5 years. The certificate applies to all medicinal products derived from the basic patent, but the additional time that can be obtained under the SPC is calculated in relation to the first product derived from the patent, authorised in the EU. 

The luminescence of diamonds is related to various defects in its structure. Almost always, luminescence centers in diamonds are related to N atoms. It is logical, because the atomic radii of C and N are nearly equal (approximately 0.77 A). Luminescence spectroscopy has proven to be the most widely used method in studies of diamonds even in comparison with optical absorption, ESR, IR and Raman spectroscopies. Himdreds of spectra have been obtained, fluorescence characteristics enter into diamond quality gemological certificates, a wide range of electronic and laser applications are based on diamond optical properties in excited states nitrogen center aggregation is controlled by the residence time of diamond in the mantle, distinction between natural... 

Another possible approach, which is broadly used, is to use high-purity substances (indirectly assayed) as standards. For use at the highest level, this approach requires the determination of all important impurities in the sample. This means not only metallic impurities, commonly stated in the manufacturers certificates, but also non-metals as oxygen, carbon, etc. The content of impurities is not always known in advance. If the total content of impurities is very low, the uncertainty of their determination does not affect the required uncertainty of the sample assay. Some other problems are discussed in Ref. [5], The need of determining the molar weight may equally apply here. 

Attempts to correlate analytical performance with other seemingly indicative laboratory characteristics, such as participation in proficiency testing schemes, regular use of certified RMs, number of years of experience and number of samples analysed per year were all equally unsuccessful. Therefore, in the absence of any simple and obvious means of identifying and preselecting only reliable laboratories as participants in certification studies, an investigation was undertaken of the validity of adopting the consensus mean (after outlier elimination) from an interlaboratory study as a certified value. 

This page is used to review the certificate information and to assign a name to the certificate. Carefully review the Issuer and Subject fields to be sure that all data fields are completed (i.e., for each data element such as CN, there is a value that follows the equal sign). 

Briefly, computation of the standard uncertainty of a calibrator solution wfll be outlined. The concentration C equals the mass M divided by the volume V (C = MIV). We will here express the standard uncertainties as relative values and derive the approximate total standard uncertainty by squared addition of the individual contributions. Starting with the mass, the purity is stated on the certificate as 99.4% 0.4%. Assuming a rectangular distribution, the relative standard deviation becomes 0.004/V3 = 0.0023. The uncertainty of the weighing process is known in the laboratory to have a CV of 0.1% or 0.0010. Thus the relative standard uncertainty of the mass becomes ... 

From the various results of the homogeneity and stability studies, it was concluded that the part of the uncertainty that cannot be evaluated by the statistical analysis (e.g. related to matrix effects, method stability, blank variations etc.) was in the order of 10% (expressed as standard uncertainty). The uncertainty related to the certification exercise was equal to Ucerj = 0.9166/ 6 = 0.0374 (or 2.0%), whereas the uncertainty factor related to homogeneity is 4.6% (see section 8.9.5). The combined uncertainty was thus estimated as follows U. = [(2.0) + (4.6) + (10) )] = 11%... 

If the soil material is due to be removed from site for disposal, then the waste disposal carrier and site accepting the waste will require a certificate of analysis determining how much asbestos is present. If the asbestos content is equal to or greater than 0.1% w/w (1000 mg/kg), then the material is classified in the UK as special waste (SI 972 1996) and can therefore only be disposed of... 

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