In-house preparation

Applications A method for multi-element determination of major elements in commercial and in-house prepared polymer/additive formulations by MIP-AES after microwave digestion with nitric acid has been reported [212], The precision obtained varied between 2 and 4.5 %, depending on the element determined. 

Catalysts used in the trickle bed reactor were supplied by Engelhard Chemical Catalyst Group prepared industrially to match in-house prepared catalysts used in our initial screening. 

The absolute K edge energy was determined by reference to V Og, which was run repeatedly to confirm edge position. The identity and crystallographic purity of the reference samples (both purchased and in-house preparations) were confirmed by x-ray diffraction and were used without further treatment. 

Calcium stock solution, 1000 jg Ca + mh - stock solutions of many elements for determination by AAS are available commercially. Details for in-house preparation will also be given. Anhydrous calcium nitrate, CafNOjfj, is dried for 1 h at 105°C, then cooled in a desiccator. Transfer 2.05 g to a 100-ml beaker containing water and stir to dissolve. Immediately add 1 ml HCI (36% m/m) to prevent hydrolysis, add with washings to a 500 ml volumetric flask, make up to the mark with water, and mix by shaking. 

Water and in-house prepared solutions should be treated by the addition of... 

Standards and QCs should be prepared from separate weighings. If kit standards are used, it is prudent to check their accuracy against an in-house preparation or standards from another lot or source. 

Isoelectric focusing on polyacrylamide gels, freshly prepared, or on those stored in sealed bags obtained commercially, or on in house prepared, contain a number of char -acteristics that are undesirable, or even unknown A) Gel polymerization products remain in the gel. These consist of unpolymerized acrylamide monomers, linear poly -mers, breakdown products of acrylamide such as Nitrilotrispropionamide... 

It should be noted that errors occurring during sub-sampling, addition of the isotopic analogue, sample preparation and isotopic equilibration are not compensated for by the use of isotope dilution analysis. However, these errors can be assessed by analysis of a suitable certified reference material or an in-house prepared standard, analysed alongside the sample. 

All laboratories that used NIST SRM obtained correct results for it. However, only 20 % of the laboratories used this SRM. An equal number of laboratories did not use any CRM, and the rest used other commercial or in-house prepared CRMs. 

The bench top analyzer was first calibrated using commercial gravimetrically based diesel standards. Two sets of commercial diesel standards and a set of in-house prepared standards were used to generate three different calibration curves for comparison. The first set of standards, made from No. 2 diesel (Vendor A), included sulfur concentration levels of 0 ppm (blank), 5 ppm, 10 ppm, 100 ppm, 500 ppm, 1000 ppm, and 3000 ppm. The second set, made from a synthetic diesel fuel matrix (Vendor B), included sulfur levels of close to 0 ppm (blank), 20 ppm, 50 ppm, 100 ppm, 200 ppm and 500 ppm. The in-house standards were made by mixing different ratios of decalin and n-butyldisulfide (CgHigS) gravimetrically with resulting sulfur concentration levels of close to 0 ppm (blank), 10 ppm, 48.6 ppm, 87.6 ppm, 320 ppm, and 946 ppm. The measured sulfur fluorescent X-ray intensity, in coimts, for each standard is listed in Table 1. 

Despite the limitations associated with plate-based tests, the majority of routine antimicrobial screening is carried out using in-house prepared plate-based assays. Commonly used examples of such plate-based tests are the four-plate test (FPT) and the modified four-plate test (mFPT) and are widely used as official screening tests within the EU. ... 

Comments Annett and Stumpf [33] reported that commercially available reagents supplied as a 0.1 M solution in toluene gave low yields compared with reactions using in-house preparations. The authors recommend the latter to ensure quantitative reactions. 

One of the major drawbacks of separation techniques when applied to food protein analysis is the availability of protein standards of suitable high quality. Commercial highly purified proteins are very often a mixture of microheterogeneous proteins, so that individual laboratories may have to rely on in-house prepared standards, and complications ensue at the validation level. 

Certified reference materials (CRMs), described in the Appendix such as those available from NIST (http //ts.nist.gov/), IAEA (http //www.iaea.org), BCR (http //www.irmm.jrc.be), or other national or international standards bodies, are occasionally used as multielement calibration standards. The chief drawbacks of these materials are the difficulty of selecting an appropriate material for all the elements of interest and the inferior accuracy of certified element content compared with in-house preparations. The most important use of CRMs is to validate the results of a measurement if the certified value is obtained when a sample is analyzed in the same manner as the unknown, then the measurement is less likely to be in... 

Bacillus strains were grown under aerobic conditions on in-house prepared LB agar plates by two passages for 24 h at 37°C. Cells were then harvested and an equivalent of three full blue plastic loops (approx. 4 mg) was added to sterile water (see Lasch et al. 2009 for details). Further steps of microbial sample preparation were the same as those used for S. aureus and E. faecium. 

Another interesting approach taken to stmcturaUy control M-N-C catalysts was first pioneered by Ma et al. [69] and involves metal-organic framework (MOF)-derived catalysts. In this work they heat-treated an in-house prepared cobalt imi-dazolate MOP to prepare a catalyst that showed promising half-cell electrochemical activity toward oxygen reduction. Proietti et al. [ 14] advanced on this work, instead... 

Aquivion E87-12S short-side chain perfluorosulfonic acid (SSC-PFSA) membrane with equivalent weight (EW) of 870 g eq and 120 pm thickness produced by Solvay Specialty Polymers was tested in a polymer electrolyte membrane water electrolyser (PEMWE) and compared to a benchmark Nation N115 membrane (EW 1100 g eq ) of similar thickness [27]. Both membranes were tested in conjunction with in-house prepared unsupported Ir02 anode and carbon-supported Pt cathode electrocatalyst. The electrocatalysts consisted of nanosized Ir02 and Pt particles (particle size 2-4 nm). The electrochemical tests showed better water splitting performance for the Aquivion membrane and ionomer-based membrane-electrode assembly (MEA) as compared to Nafion (Fig. 2.21). Lower ohmic drop constraints and smaller polarization resistance were observed for the electrocatalyst-Aquivion ionomer interface indicating a better catalyst-electrolyte interface. A current density of 3.2 A cm for water... 

The primary purpose of a reaction database system is to provide quick and easy access to the reaction literature. Users of synthesis planning programs have a need for such access to the literature in elaborating routes suggested by an analysis. An interface between LHASA and ORAC has recently been developed to provide such a link. The interface allows literature precedents for synthetic steps proposed by LHASA to be retrieved automatically from ORAC s database of over 120,000 reactions and to be displayed to the user on an ORAC Display Form. Company databases can also be accessed to search and display in-house preparative methods and processes in conjunction with databases supplied by ORAC Ltd. 

Suarez-Gomez, A., Saniger-Blesa, J.M., and Calderon-Pinar, F. (2009) The effects of aging and concentration on some interesting sol-gel parameters a feasibility study for PZT nanoparticles insertion on in-house prepared PAA matrices via electrophoresis. /. Electroceram., 22, 136-144. 

Impregnation of layers with a chiral selector for use in enantiomer separations has usually been carried out by mixing the compound with silica gel to prepare a slurry for in-house preparation of the layer. For example, Bhushan and Martens [18] reported use of this method for preparing layers containing selectors such as (-F)-tartaric acid or (-F)-ascorbic acid, erythromycin, vancomycin, L-lysine and L-arginine, and (—)-brucine. 

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