Precipitation, automatic

Place a mixture of 53 g. of A.R. lactic acid (85-88 per cent, acid), 75 g. (85-5 ml.) of commercial anhydrous isopropyl alcohol, 300 ml. of benzene and 20 g. of Zeo-Karb 225/H (1) in a 700 ml. bolt-head flask, equipped with an automatic water separator (e.g., a large modified Dean and Stark apparatus with a stopcock at the lower end, see Fig. Ill, 126, 1) carrying an efficient reflux condenser at its upper end, and a mercury-sealed stirrer (alternatively, the hquid-sealed stirrer shown in Fig. 11,7,11, c. may be used). Reflux the mixture, with stirring, on a steam bath for 5 hours or until water no longer collects in appreciable amount in the water separator run off the water from time to time. Filter off the resin at the pump and wash it with two 25 ml. portions of benzene. Shake the combined filtrate and washings with about 5 g. of precipit-ated calcium... 

V. Reyes, Comparison between TraditionalandModem Automatic Controllers on Eull-scale Precipitators, Seventh Symposium on Transfer and Utilization of Particulate Control Technology, Nashville, Term., March 1988, F. L. Smidth Co., Valby, Denmark. 

Trisodium phosphate is strongly alkaline many of its appHcations depend on this property. For example, many heavy-duty cleaning compositions contain trisodium phosphate as a primary alkalinity source. The crystalline dodecahydrate itself is marketed as a cleaning compound and paint remover. Traditionally, trisodium phosphate has been used in water softening to remove polyvalent metal ions by precipitation as insoluble phosphates. Because the hypochlorite complex of trisodium phosphate provides solutions that are strongly alkaline and contain active chlorine, it is used in disinfectant cleaners, scouring powders, and automatic dishwashing formulations. 

Assay of beryUium metal and beryUium compounds is usuaUy accompHshed by titration. The sample is dissolved in sulfuric acid. Solution pH is adjusted to 8.5 using sodium hydroxide. The beryUium hydroxide precipitate is redissolved by addition of excess sodium fluoride. Liberated hydroxide is titrated with sulfuric acid. The beryUium content of the sample is calculated from the titration volume. Standards containing known beryUium concentrations must be analyzed along with the samples, as complexation of beryUium by fluoride is not quantitative. Titration rate and hold times ate critical therefore use of an automatic titrator is recommended. Other fluotide-complexing elements such as aluminum, sUicon, zirconium, hafnium, uranium, thorium, and rate earth elements must be absent, or must be corrected for if present in smaU amounts. Copper-beryUium and nickel—beryUium aUoys can be analyzed by titration if the beryUium is first separated from copper, nickel, and cobalt by ammonium hydroxide precipitation (15,16). 

A unit is available in which electrostatic precipitation is combined with a dry-air filter of the type shown in Fig. 17-64Z . In another unit an electrostatic field is superimposed on an automatic filter. In this case the ionizer wires are located on the leading face of the unit, and the collecting electrodes consist of alternate stationary and rotating parallel plates. Cleaning in this case is automatic and continuous. 

Abnormal initiation of electrical impulses occurs as a result of abnormal automaticity. If the automaticity of the SA node increases, this results in an increased rate of generation of impulses and a rapid heart rate (sinus tachycardia). If other cardiac fibers become abnormally automatic, such that the rate of initiation of spontaneous impulses exceeds that of the SA node, other types of tachyarrhythmias may occur. Many cardiac fibers possess the capability for automaticity, including the atrial tissue, the AV node, the Purkinje fibers, and the ventricular tissue. In addition, fibers with the capability of initiating and conducting electrical impulses are present in the pulmonary veins. Abnormal atrial automaticity may result in premature atrial contractions or may precipitate atrial tachycardia or atrial fibrillation (AF) abnormal AV nodal automaticity may result in junctional tachycardia (the AV node is also sometimes referred to as the AV junction). Abnormal automaticity in the ventricles may result in ventricular premature depolarizations (VPDs) or may precipitate ventricular tachycardia (VT) or ventricular fibrillation (VF). In addition, abnormal automaticity originating from the pulmonary veins is a precipitant of AF. 

A reference solution is prepared by a dilution method. A known quantity of sample is dissolved in a known volume of the system buffer of known pH the amount of sample is X times less than in the above case in order to avoid precipitation in the formed solution. The spectrum is immediately taken by the UV spectrophotometer, to take advantage of the possibility that solution may be supersaturated (i.e., solid should have precipitated, but because not enough time was allowed for the solid to precipitate, the solution was temporarily clear and free of solid). Mathematical treatment of the spectral data yields the AUC of the reference sample solution, AUQ . The ratio R = AUCS/AUCS is used to automatically recognize the right conditions for solubility determination when the reference has no precipitate, and the sample solution is saturated with precipitate. Under these conditions, solubility is determined from the expression... 

HSPF can be run with a time step ranging from 1 minute to 1 day. Data can be stored in the TSS with a similar range of intervals. The system will automatically convert time series from one interval to another, as they are transferred between the TSS and the machine memory. This means, for example, that a Pervious Land-segment could be run at an interval of 1 hour, using 15 minute precipitation data and daily evaporation data (stored on the TSS) as inputs. 

Lebel [224] has described an automated chelometric method for the determination of sulfate in seawater. This method utilises the potentiometric end-point method for back titration of excess barium against EDTA following precipitation of sulfate as barium sulfate. An amalgamated silver electrode was used in conjunction with a calomel reference electrode in an automatic titration assembly consisting of a 2.5 ml autoburette and a pH meter coupled to a recorder. Recovery of added sulfate was between 99 and 101%, and standard deviations of successive analyses were less than 0.5 of the mean. 

Automatic atrial tachycardias such as multifocal atrial tachycardia appear to arise from supraventricular foci with enhanced automatic properties. Severe pulmonary disease is the underlying precipitating disorder in 60% to 80% of patients. 

Precipitating the coupling component with acetic acid or phosphoric acid often automatically provides the buffer that is necessary to maintain a certain pH throughout the coupling reaction. Otherwise, buffers such as sodium acetate, sodium phosphate, or calcium carbonate ( chalk coupling ) must be added. 

In Step 7, after the energetics hydrolysate from the continuously stirred tank hydrolysis operation has been pumped into a holding tank, acid is added to precipitate aluminum, and the hydrolysate is filtered through an automatic filter press to remove precipitated aluminum compounds. The liquid effluent goes to the dunnage hydropulper (Step 9). The filter cake from the press is sent to an electrically heated screw conveyor (Step 15) for 5X treatment. 

AM-001, and mannanase B properties are similar to those of P-mannanase M-III. Furthermore, the Ouchterlony double diffusion test showed that these five enzymes gave fused precipitation lines. However, N-terminal amino acid sequences of the five mannanases determined by an automatic amino acid sequencer revealed that the N-terminal amino acid sequence from amino acid 1 (Asn) to 9 (Gin) of the Bacillus sp. AM-001 enzymes coincides with those from amino acid 4 (Asn) to 12 (Asn) of the R coll JMlOl (pMAH3) enzymes as shown in Fig. 4. This may reflect differences in the specificities of the signal peptidases of the two bacteria. 

Horticulture Pit. The horticulture pit was constructed in 1969-70 and has been in continuous use since that time. The 8.8 x 3.4 m concrete pit has an average depth of 1 m and has been filled with alternate 30 cm layers of gravel and soil as shown in Figure 1. The soil is a silt loam (Clarion-Nicolett-Webster) characteristic of Central Iowa. A cover closes automatically to prevent precipitation from entering. A tile system constructed below the concrete floor of the pit connects to a sump for sampling of the ground water. The 30,000 L pit has had over 30 kg of more than 40 different pesticides deposited since beginning operation. 

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