Standards primary/secondary

Internal intensity standards Primary Secondary Quantitative Fluorophlogopite CSRM 675 Tungsten, silver, quartz and diamond Al203 CSRM 676 ... 

The U.S. Clean Air Amendments of 1977 define two kinds of air quality standards primary standards, levels that will protect health but not necessarily prevent the other adverse effects of air pollution, and secondary standards, levels that will prevent all the other adverse effects of air pollution (Table 22-7). The amendments also define air quality levels that cannot be exceeded in specified geographic areas for "prevention of significant deterioration" (PSD) of the air of those areas. Although they are called "increments" over "baseline air quality" in the law, they are in effect tertiary standards, which are set at lower ambient levels than either the primary or secondary standards (Table 22-8). 

Rubin and Blossey standardized the experimental conditions for the Serini reaction, using freshly activated zinc in refluxing xylene for 20-24 hr with vigorous stirring yields of68-100 % could then be obtained. They noted, however, that the presence of a 16a- or -methyl group markedly decreased the yield, and that a primary-secondary glycol monoacetate failed to react. 

In titrimetry certain chemicals are used frequently in defined concentrations as reference solutions. Such substances are referred to as primary standards or secondary standards. A primary standard is a compound of sufficient purity from which a standard solution can be prepared by direct weighing of a quantity of it, followed by dilution to give a defined volume of solution. The solution produced is then a primary standard solution. A primary standard should satisfy the following requirements. 

To meet the specified standard,4 wastewaters are often subjected to a series of treatment processes before they are discharged into the environment, particularly, water bodies. The treatment processes include physical, chemical, and biological processes that may be applied singly or collectively. The collective application of the processes can be employed in a variety of systems classified as primary, secondary, and tertiary wastewater treatment, to achieve different levels of contaminants removal.2... 

In a preliminary study, in situ generated B-alkylcatecholboranes were allowed to react with PTOC-OMe under irradiation with a standard 150 W lamp. The S-pyridyl products coming from primary, secondary and tertiary alkyl radicals were isolated in moderate to good yields [88]. Based on these initial results, a procedure for conjugate addition to various activated alkenes was developed. A one-pot procedure involving hydroboration of an alkene with catecholborane followed by irradiation in the presence of five equivalents of an activated alkene and three equivalents of the chain transfer reagent PTOC-OMe was developed (Scheme 36) [88]. 

This method is of quite general applicability and the carbonyl compound may be an aldehyde, a ketone, or an ester. Similarly, the halide may be chloride, bromide, or iodide although yields are generally lower with iodides. Alkyl and aryl halides react with equal facility and the alkyl halide may be primary, secondary, or tertiary. A few examples of the yields obtained with a variety of reagents are given in Table I (the yields quoted are obtained by g.l.c. analysis of the reaction mixture using an internal standard ). 

POLLUTANT PRIMARY STANDARDS. .. -n. SECONDARY AVERAGING TIMES STANDARDS... 

ASTM D 2073-92, Standard Test Methods for Total, Primary, Secondary, and Tertiary Amine Values of Fatty Amines, Amidoamines and Diamines by Referee Poten-tiometric Method, ASTM, Philadelphia, PA, 1992. 

Historically the first fully unsaturated azepine was obtained by Wolff in 1912 by the decomposition of phenyl azide in aniline. However, the actual structure of this product, named dibenzamil , remained unknown until 1955, when Huisgen and coworkers showed it to be an anilinoazepine, originally formulated as the 7-anilino-2H-azepine, but later corrected, mainly on the basis of HNMR evidence, to the 2-anilino 3H-tautomer (221 R1=PhNH R2 = H). Subsequently, the thermolysis and photolysis of aryl azides in primary, secondary and, in certain instances, tertiary amine solution has become a standard method for the preparation of 2-amino-3/f-azepines (79AG(E)900,8lAHC(28)23l). 

Fig. 3. Comparison of different enzyme-linked immuno sorbent assay (ELISA) methods adapted for immuno-polymerase chain reaction (IPCR). Dependent on the purification grade of the sample to be analyzed and the availability of specific and functionalized antibodies, several typical ELISA protocols were adapted to IPCR. In the direct approach (A), the pure antigen is immobilized to the microplate surface and subsequently detected by a labeled specific antibody. If no labeled antibody is available (e.g., because of unpurified ascites fluid containing the antibody or loss in activity following labeling), a standardized labeled secondary species-specific antibody is used for detection of the primary antigen-specific antibody (B). For the detection of the antigen from matrices such as serum, plasma, tissue homogenate, and so on, a capture antibody immobilized to the microplate surface was used either in a direct (C) or indirect (D) sandwich approach, with the latter one additionally including a secondary species-specific detection antibody. For different methods of coupling antibody and DNA, abbreviated by in this figure, compare Fig. 2. Note that protein A chimeras (Fig. 2A) are not compatible with capture antibodies (Fig. 3C, D).

Hierarchies, such as primary, secondary, and working level, or certified RMs and RMs are extensively used in describing traceability chains. Whilst such terms can be useful in explaining processes and links, they can also be confusing. For this reason their use has been limited in this paper. It is considered preferable to describe hierarchies in terms of the associated uncertainties. It can also be noted that, whereas in physical measurement it is common to have a hierarchy of references of the same basic type (e.g., a series of mass standards), this is rare in chemical measurement where the chain usually contains only one chemical RM, linked to a higher reference by a measurement process. 

The accelerated rate for alcoholysis with le, which was observed for the 10 % Pd/C catalytic system, was also seen with the Mn(CO)sBr catalyst. Reactions of le with primary, secondary or tertiary alcohols resulted in moderate yields of the corresponding silyl ketals after 2 h (Table 8 and 9). When mono-alkoxy silane from 3-hydroxy butyrate (lg) was treated with homoallyl alcohol in the presence of Mn(CO)sBr as the catalyst under the standard conditions, 76 % of the silyl ketal was obtained. These silyl ethers possess neighboring carbonyl groups that can participate in the reaction by forming a more reactive pentacoordinated silicon center upon addition of the silane to the metal center.. 

A standard primary and secondary reforming front end of the plant will operate at proven process conditions. Scale-up of the reforming section is straight-forward when using a top-fired box reformer with a cold outlet manifold system. The size of the reformer is much smaller than reformers currently designed for large-scale methanol projects218. 

The EU Commission Decision EC 2002/657 prescribes the use of RMs or CRMs [4]. Eurachem has published a document that provides instructions to analytical chemists on the selection and use of RMs [31]. Different types of RMs exist, namely, pure substances, standard solutions, matrix RMs, physical-chemical RMs, and reference objects or artifacts. The difference between RMs and CRMs lies in that the values or properties of a CRM are certified during a collaborative trial according to a well-defined protocol, whereas the values or properties of an RM are defined, but have not been established through a collaborative trial. The following classes are generally used for RMs primary, secondary, and in-house or working RMs. The uncertainty associated with primary RMs is the smallest, while in-house RMs have the largest uncertainty. 

From the analysis of air pollutants and their effects, the NAAQS described above were developed by the US EPA based on requirements of the Clean Air Act. This was done by defining the criteria pollutants to measure air quality, and then by determining the acceptable concentrations under health protection criteria (known as primary standard) a secondary standard was also defined to protect public welfare and prevent environmental and property damage. The criteria pollutants for air quality thus selected were CO, Pb, N02, O3, PM]0, PM25, and... 

A primary standard is used to establish a secondary standard. A secondary standard is defined as a standard whose value is assigned by comparison with a primary standard of the same quantity ". It is often the secondary standard that the analyst will use. 

Silane NM2 is capable of masking primary, secondary, and tertiary alcohols by using standard protocols (imidazole or NEts as base, ambient temperature for primaiy/secondary alcohols). However, in line with the TBM2 group, the introduction of the more sterically demanding NM2 group requires harsher reaction conditions (elevated reaction temperatures, prolonged reaction times) for the formation of NM2 silyl ethers of tertiary alcohols. 

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