Substrate sodium chloride

For potassium chloride, Clark (3) observed phase transitions to take place at temperatures lower than on a sodium chloride substrate. We deduce that the surface field of potassium chloride is greater than that of sodium chloride or sodium bromide. 

More recently Tibbitt, Bell and Shen (56,57) carried out quantitative determinations of the structure of plasma polymerized hydrocarbons by infrared spectroscopy. Typical spectra of films deposited on sodium chloride substrates are shown in Figure 15. Absorptions peaks were identified to be associated with various group frequencies, corroborated with the findings from NMR spectra of dilute solutins of the oily products. From the knowledge of the extinction coefficients, concentrations of the functional groups in the plasma polymerized materials were determined. 

Figure 15. IR spectra of plasma-polymerized films on sodium chloride substrate...

Duncan and Frankenthal report on the effect of pH on the corrosion rate of gold in sulphate solutions in terms of the polarization curves. It was found that the rate of anodic dissolution is independent of pH in such solutions and that the rate controlling mechanism for anodic film formation and oxygen evolution are the same. For the open circuit behaviour of ferric oxide films on a gold substrate in sodium chloride solutions containing low iron concentration it is found that the film oxide is readily transformed to a lower oxidation state with a Fe /Fe ratio corresponding to that of magnetite . 

Energy substrates include dextrose solutions and fat emulsion. Solutions used to supply energy and fluid include dextrose (glucose) in water or sodium chloride, alcohol in dextrose, and IV fat emulsion. Dextrose is a carbohydrate used to provide a source of calories and fluid. Alcohol (as alcohol in dextrose) also provides calories. Dextrose is available in various strengths (or percent of the carbohydrate) in a fluid, which may be water or sodium chloride (saline). Dextrose and dextrose in alcohol are available in various strengths (or percent of the carbohydrate and percent of the alcohol) in water. Dextrose solutions also are available with electrolytes, for example, Plasma-Lyte 56 and 5% Dextrose. Calories provided by dextrose and dextrose and alcohol solutions are listed in Table 58-1. 

In the Phadebas TM amylase test (72) (Pharmacia Labs) the substrate was a water insoluble cross-TTnked blue starch in tablet form which also contains some inert ingredients, sodium and potassium phosphate buffer salts and sodium chloride. This polymer was hydrolyzed by amylase into water soluble blue starch fragments. After centrifugation the absorbance of the blue supernatant was proportional to the activity of amylase present in the test samples. The day to day variation on a quality control serum had a coefficient of variation of 2.7% based on 30 days of data in our laboratory. The method is simple, reproducible and uses microquantities of serum. 

Synthetic Method 1 6-(dimethylamino)-3-(N-acetyl-N-methylamino)-10-acetylphenothiazine 8a (procedure from US. Patent 4,652,643).5 A mixture of 9.0g of 6-(dimethylamino)-3-(methylamino)phenothiazin-5-ium chloride (Azure B), 150.0ml of acetic anhydride, and lO.Og of zinc dust was maintained at reflux temperature for approximately 4 hs. After the reaction mixture was cooled to ambient temperature, it was poured into ice water with stirring and 300ml of toluene was added. After stirring for approximately 30 min the toluene layer was separated and washed twice, once with tap water and once with saturated aqueous sodium chloride solution. The toluene was then distilled off at reduced pressure. The residue which remained was dissolved in ethyl acetate and separated into various components by subjecting the solution to column chromatography using silica gel as substrate. Elution with ethyl acetate yielded a white-colored solid. 

The substrate commonly employed is 0.5-1.0% of pectin in 50-200 mM sodium chloride (20-60 ml) at a suitable pH and 30°. The pectinesterase activity is mostly expressed in micro-equivalents of ester hydrolyzed per minute at the given pH and temperature. The use of a variety of units of activity, which was complicated and prevented ready comparison of the results of various authors, has now been discontinued. 

Lineweaver and Ballou49 have proposed a pectinesterase unit ( PE. u. ) for expressing PM activity. One such unit is equivalent to 1/930 PMU under the same experimental conditions or the quantity of enzyme that, at 30° and optimum pH, will catalyze the hydrolysis of pectin at an initial rate of one milliequivalent ester bonds per minute in a standard substrate (0.5% citrus pectin containing 8-11% methoxyl) and 0.15 M sodium chloride. The use of the latter unit is unfortunate since the values obtained for the activity in ordinary plant materials are obtained in the third decimal place and because the experimental conditions are so... 

Typically, the electrodes are of lead dioxide on a titanium substrate in the form of horizontal perforated plates, usually 5-40 mm apart, depending on the conductivity of the liquid. A potential difference of 5-10 V may be applied to give current densities of the order of 100 A/m2. Frequently, the conductivity of the suspension itself is adequate, though it may be necessary to add ionic materials, such as sodium chloride or sulphuric acid. Electrode fouling can usually be prevented by periodically reversing the polarity of the electrodes. Occasionally, consumable iron or aluminium anodes may be used because the ions released into the suspension may then assist flocculation of the suspended solids. 

Perlmutter used an oxymercuration/demercuration of a y-hydroxy alkene as the key transformation in an enantioselective synthesis of the C(8 ) epimeric smaller fragment of lb (and many more pamamycin homologs cf. Fig. 1) [36]. Preparation of substrate 164 for the crucial cyclization event commenced with silylation and reduction of hydroxy ester 158 (85-89% ee) [37] to give aldehyde 159, which was converted to alkenal 162 by (Z)-selective olefination with ylide 160 (dr=89 l 1) and another diisobutylaluminum hydride reduction (Scheme 22). An Oppolzer aldol reaction with boron enolate 163 then provided 164 as the major product. Upon successive treatment of 164 with mercury(II) acetate and sodium chloride, organomercurial compound 165 and a second minor diastereomer (dr=6 l) were formed, which could be easily separated. Reductive demercuration, hydrolytic cleavage of the chiral auxiliary, methyl ester formation, and desilylation eventually led to 166, the C(8 ) epimer of the... 

The other major casein in cheese is /3-casein, but it is generally not hydrolyzed by rennet in low-pH cheeses. Alkaline milk protease (plas-min) plays the major role in the hydrolysis of /3-casein (Richardson and Pearce 1981). The plasmin level in cheese is related to the pH of the curd at whey drainage, since plasmin dissociates from casein micelles as the pH is decreased. Richardson and Pearce (1981) found two or three times more plasmin activity in Swiss cheese than in Cheddar cheese. Swiss cheese curds are drained at pH 6.4 or higher, while Cheddar cheese curds are drained at pH 6.3 or lower. Proteolysis of /3-casein is significantly inhibited by 5% sodium chloride. The inhibitory influence of sodium chloride is most likely due to alteration of /3-casein or a reduction in the attractive forces between enzyme and substrate (Fox and Walley 1971). 

The site of formation of renin is not known, although the indirect and circumstantial evidence favors slightly the juxtaglomerular apparatus rather than the tubules as a source (18). Crude renin, however, is extracted readily from renal cortex by saline extraction, acidification, and precipitation with ammonium sulfate and sodium chloride. Other active protein substances are likewise extracted, and their separation from renin is often a matter of considerable difficulty. The renin substrate, an arglobulin, is found in blood serum and is probably formed by the liver. It can be easily salted out of beef serum as a crude preparation. 

A solution of the substrate (1.71 g, 10.06 mmol) in THF (5 ml) was added dropwise, under nitrogen, to a stirred mixture of diphenyliodonium fluoride (1.51 g, 5.03 mmol) in THF (15 ml) at — 40°C. After 3 h at this temperature, the reaction mixture was allowed to warm to 10°C and was kept at room temperature for 30 min. Then it was treated with water (3 ml), and concentrated the residue was dissolved in dichloromethane (100 ml) and the solution was washed with water (2 x 20 ml) and saturated aqueous sodium chloride (15 ml). After drying and concentration, the oil obtained was purified by flash column chromatography on silica gel (hexanes-dichloromethane) to give 2-phenylcyclohexanone (1.48 g, 88%), m.p. 55-57°C. 

Pipet 20.0 mL of the Buffered Substrate Solution, previously heated in the water bath for 20 min, into a 50-mL Erlenmeyer flask, and add 5.0 mL of 0.5% sodium chloride solution, also previously heated in the water bath for 20 min. Place the flask in the water bath. 

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