Solution reduction

The heptamethylene glycol was separated by continuous ether extraction from the alkaline reduction solution after the latter had been diluted and distilled to remove the alcohol. The nonamethylene glycol was separated from the alkaline liquor by decantation (as above) and distilled. All the others were crystallized from benzene (without alcohol). Equally successful results have also been obtained with larger runs (e.g., 0.5 mole of ester),... 

E reduction solution 0.025 g citric acid and 0.185 ml 27% formaldehyde in 100 ml ddH2 0 (stabilize for a longer period if frozen)... 

A method for the determination of personal exposure to benzidine-based dyes has been developed. This procedure involved the reduction of benzidine-based dye filter samples to free benzidine with neutral buffered sodium hydrosulfite solution. The benzidine-containing reduction solution was then analyzed by high performance liquid chromatography. The reduction was found to be quantitative by visible-spectrum analysis. This reduction and analysis method was evaluated with four benzidine-based dyes over the range from 12 to 300 micrograms per sample. Precision for the reduction and analysis of the four dyes falls within % coefficient of variation. This method can differentiate between benzidine-and benzidine congener-based dyes. Results are reported in terms of free benzidine. 

Next the material from the filter flask is poured over the tin and the 1-1. flask stoppered with the one-hole stopper. The temperature in the water bath is maintained at 25 2° and the reduction continued for exactly 2 hours. During this time the reduction solution will go from blue to purple to reddish-brown or green. Shortly before the reduction is over, a stoppered, 500-ml. Erlenmeyer flask is packed in crushed ice in a Dewar jug. The air in the flask is displaced with hydrogen chloride gas to avoid air oxidation. When the reduction is finished, the solution is decanted into the 500-ml. flask, the remaining tin being drained. This tin can be washed and reused. The reduction solution is resaturated with hydrogen chloride gas. (This step requires... 

Eh gradient below zone o phytoplankton - reduction solution of iron... 

During the evolution of the trapped arsines it is possible to stop the pump to conserve reductant solution, but then the sensitivity of the analysis is reduced as poor atomization results from the absence of air-hydrogen flames at the ends of the atomization tube. 

Sun Y-P, Atorngitjawat P, Meziani MJ. Preparation of silver nanoparticles via rapid expansion of water in carbon dioxide microemulsion into reductant solution. Langmuir 2001 17 5707-5710. 

NO3" -N and N02 -2 was measured on a Technican AutoAnalyzer 11 by the hydrazine sulfate reduction procedure. The reagents used were 12 g NaOH + 2 ml Brij-35 (30%)/ reduction solution 500 mg hydrazine sulfate 25 mg CUSO4 5 H2O color reagent 10 g suifanilamide, 0.8 g N-[Naphthyl-(l)]-ethylene... 

In the partition contactor, plutonium was converted to inextractable, trivalent Pu (N03)3 by a reductant solution of ferrous sulfamate containing aluminum nitrate to keep uranium in the hexone phase. Plutonium was thus separated from uranium and transferred back to the aqueous phase along with the aluminum nitrate. Impure plutonium nitrate was purified by additional cycles of solvent extraction, not shown. 

Reduce inert gas flow rate to ca 600 mU/min Flush reduction solution (0.5 mL/s) into the reaction chamber with a pressure of 150 hPa on the reduction solution vessel 12... 

The formation of silver (Ag) nanoparticles in the rapid expansion of PFPE-NH4-stabilized aqueous AgN03-in-C02 microemulsion into a room-temperature reductant solution has been reported (9). In order to use Ag as a reference in this study, the same preparation of Ag nanoparticles via RESOLV was repeated. 

Su C, Ludwig RD. (2005). Treatment of hexavalent chromium in chromite ore processing residue solid waste using a mixed reductant solution of ferrous sulphate and sodium dithionite. Environmental Science and Technology 39 6208-6216. 

An attractive modification of this method described above is the following. An amount of 200 mg of oil (10 droplets) and 20 mg of magnesium carbonate are weighed into calibrated Pyrex tubes of 15 ml. The Pyrex tubes are placed in an aluminium block with holes (Fig. 6.6). The aluminium block is heated on an electrical hot plate at a maximum 350 C till the oil is charred to a dry black mass. The tubes are then placed in a rack (Fig. 6.6) and ashed in a muffle furnace at ca. 550 °C to a white ash. After the ash is dissolved, the reaction with reduction solution and sulphate-molybdate reagent is carried out directly in the Pyrex tube. After making up to 15 ml, the absorption at 720 nm is also measured directly in the Pyrex tube. 

Quartz tube atomizer Some elements like antimony, arsenic, bismuth, lead, tin, can be vaporized as molecules (e.g., hydrides) by chemical reaction at room temperature. For this purpose a reductant solution (NaBH4, SnCli) is added to the sample solution and the obtained gaseous hydrides are transported to the quartz tube atomizer (hydride... 

ELTECH Systems Corporation supplies a Voltage Reduction Solution (VRS) [207], which is essentially a solution of chloroplatinic acid. When added to the catholyte, it is electrodeposited in a high surface form and reduces cathodic overvoltage. This in situ activation is claimed to be very economical and convenient as long as the residual platinum species in the catholyte caustic has no adverse effect on the end use of the caustic soda. 

The wavelength is adjusted to 217.6 nm with a spectral slit width of 0.7 nm. The setting of the hydride system depends on the type of instrument used and must be optimized for each individual instrument. Helium is ptefened as the inert gas since it yields greater sensitivity. The temperature of the quartz cuvette is 900°C the reduction solution used is 3% NaBH4 in 1% NaOH. There must be a distinct excess of acid present if the formation of SbHs is to take place quantitatively. 

Are there alternative risk reduction solutions that we might consider ... 

Figure 11. Response time of the redox optomembrane in function of PVC (arrows mark the addition of oxidant and reductant solutions).

Figure 13. Response time of the redox optomembrane based on cellulose membrane containing DPA (arrows mark the addition of oxidant and reductant solutions) (Reprinted from Sensors and Actuators B, 38-39, 207, 1997, with permission from Elsevier Science, The Boulevard, Langford Lane, Kidlington 0X5 1GB, UK).

---