Chlorine concentration, drop

The Auger depth-composition profiles vapor-degreased surfaces and a "blank" surface are compared in Figures 8(a) and (b). Figure 8(b) shows that the small amount of chloride on the "blank" surface is a maximum at the outer surface and drops to undetectable as the film is penetrated 2 nm. By contrast, on the specimens exposed to vapor degreasing, the chloride concentration consistently reached a maximum 2 to 4 nm within the film. This increased level of chlorine in the film appeared to be related to a decrease in the ratio of iron to chromium oxides, particularly at the depth where the chlorine concentration was a maximum. 

Figure 6.65 gives results for feed composition disturbances. At 0.1 h, the chlorine concentration in the feed is increased from 10 to 12.5 mol%, and at 1.5 h it is decreased to 7.5 mol%. The maximum deviation in T(6) temperature is about 2 K for the very large drop in feed composition. The temperature loop is somewhat oscillatory for the low feed composition and low coolant flow conditions, so some controller retuning would be advisable. 

The chlorine concentration has been repeatedly measured in a well, as shown in Fig. 6.20. What hydrological conclusions may be reached Two water types, of different chlorine concentrations, intermix. What is the nature of this mixing To answer this question, the nature of the time periodicity has to be discussed. A case study of this kind has been reported by Tremblay et al. (1973) from a coastal well on Prince Edward Island (Fig. 6.21). It was pumped daily from 8 a.m. to 5 p.m., and the chlorine concentration was measured at these hours. The chlorinity increased during the day and dropped until the following morning. This simple series of... 

The sum of chlorine gas, sodium hypochlorite, calcium hypochlorite, hydochlorous acid, and hypochlorite ion is known as the free or free available chlorine. Most polyamide composite membranes have little tolerance for free chlorine they can tolerate about 200 - 1,000 ppm-hrs of exposure (e.g., 200 hours at 1 ppm of free chlorine) before rejection drops to unacceptable levels. While the pretreatment to RO should have a free chlorine residual of about 0.5 to lppm, the influent to the RO must be dechlorinated to bring the free chlorine concentration down to less than 0.02 ppm. 

The decrease in chlorine concentration in the solution with an increase in temperature and the related transition of the reaction to the diffusion phase leads to a local deficiency in chlorine. As the temperature changes from 100° to 200° C., the content of decachloropentane drops greatly (Table II). With an increase in temperature, the content of the degradation and dehydrochlorination products continuously increase. 

As reported by SeiTano and de Lasa (1999) 2-chlorophenol, 2-4-dichlorophenol, phenol and MeB display different degrees of adsorption dmdng the dark reaction (light turned off). For 2-4-dichlorophenol, the dimensionless concentration drop dm ing the dark period was close to 0.75, contrasting with the 0.6 decrease for 2-chlorophenol and the 0.08 reduction for phenol. The addition of chlorine atoms to the phenol molecules further enhances pollutant adsoiption on the Ti02 -mesh of Photo-CREC-Water I. 

The chlorine leak occurred from one of two one-ton capacity chlorine tanks connected with a manifold at a water treatment plant. A room chlorine monitor and alarm signaled employees that a leak occurred at 4 50 a.m. on September 2, 1988. However, chlorine concentrations in the room were too great for employees to enter. The Morristown fire department was notified at 5 07 a.m. the fire department entered the room using self-contained breathing apparatus but was unable to cap the leak. The leak was described as a chlorine liquid jet escaping from the tank. The liquid dropped to the floor and vaporized. The chlorine corroded the electrical components, eventually starting a fire in the transformer room. Power to the plant was cut off at 7 a.m. Chorine hydrate slush began to build up in the area. At noon a team from the chlorine supplier arrived on site and capped the leak. Before the leak was capped, an estimated 2,400 to 3,000 pounds of chlorine had escaped. 

The preceding reactions occur throughout the stratosphere and are responsible for depletion of ozone on a global scale. The extreme ozone depletion at the South Pole, however, did not at first seem to be consistent with the kinetics of the knovm ozone-destroying reactions and the known free chlorine concentrations. The discrepancy turned out to be due to heterogeneous chemistry (Fig. 4.47). Under wintertime conditions when polar stratospheric temperatures drop below approximately —78 °C, polar stratospheric clouds (PSCs) are formed. These clouds can form from H2SO4/H2O droplets, which take up HNO3 under cold temperatures from ice crystals formed from the condensation of water and from solid... 

Under normal conditions, solutions of sodium (and other) chlorites when acidified do not evolve chlorine dioxide in dangerous amounts. However, explosive concentrations may result if acid is dropped onto solid chlorites. 

The scavenging of (HC1)( ) by trace concentrations of chlorine explains the abrupt initial drop in the yield of hydrogen from HC1 at —77 °C (see Fig. 5(b)). The more gradual reduction of G(H2) over the [C12]/[HC1] range from 10-4 to 10 2 has been attributed to a competition between HC1 and chlorine for hydrogen atoms, viz. 

Today we know that CFCs break up when they reach the ozone layer, releasing chlorine atoms. The chlorine atoms destroy ozone molecules faster than the ozone can regenerate from oxygen gas. Studies in the past ten years have shown dramatic drops in ozone concentration at specific locations. Since ozone protects... 

Apparent photosynthetic rates in plants subjected to SO2 or NO exposures with constant pollutant concentrations, as illustrated in Figure 1, characteristically dropped rapidly upon initiation of treatment to new depressed equilibrium levels which could be maintained for several ho irs. Hydrogen fluoride, conversely, caused CO2 uptake rates to decline more gradually during fumigation. Chlorine, O3 and NO2 exposures induced inhibition rate responses which were intermediate between these... 

Mixtures containing potassium chlorate can be quite susceptible to the presence of a variety of chemical species. Acids can have a dramatic effect - the addition of a drop of concentrated sulfuric acid (H 2SO 4) to most KCIO 3 /fuel mixtures results in immediate inflammation of the composition. This dramatic reactivity has been attributed to the formation of chlorine dioxide (ClOj) gas, a powerful oxidizer [5]. The presence of basic "neutralizers" such as magnesium carbonate and sodium bicarbonate in KC10 3 mixtures can greatly lower the sensitivity of these compositions to trace amounts of acidic impurities. 

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