Breakpoint, adding

This reaction is called the breakpoint chlorination the combined chlorine level, which was rising as more chlorine was added, now drops suddenly. Free chlorine then rises without a corresponding rise in combined chlorine. This indicates that the pool pollution has been successfully oxidized by chlorine. 

Most commonly, gaseous chlorine is added daily to large cooling systems, whereupon it combines with all possible reactants, as measured by the chlorine demand. When this demand has been satisfied, the breakpoint is reached, and a continuous free residual of chlorine is then permitted to... 

The breakpoint frequency analysis assumes that the pore resistance Rpo, the polarization resistance of the defect, Rp, and the double layer capacitance in the defects, Cdi, scale with the area of substrate-coating delamination, Ad by... 

Figure 11.13. General scheme of breakpoint chlorination difference between total residual Cl and chlorine dose reflects chlorine demand, primarily from ammonium and amines. Before breakpoint, most Cl is in combined forms, primarily mono- and dichloramine after the breakpoint, the combined residual consists of slow-reacting organic chloramines. Added Cl remains in free form after the breakpoint. Sharpness of breakpoint and minimum observed Cl concentration depend on pH, temperature, and time of reaction. Loss of residual Cl at breakpoint is caused by oxidation of di- and trichloramines to Nj according to reactions 33a and 33b and other reactions. (Adapted from Brezonik, 1994.)...

Figure 2 shows a chlorine breakpoint curve, with the amount of chlorine shown on the horizontal scale and the amount of available chlorine shown on the vertical scale. According to the curve, the chlorine residual will not appear until 3 mg/L of chlorine is added. After this point, additional chlorine will result in an increase in residual. However, at about 6 mg/L, further additions of chlorine actually bring about a decrease in residual until the breakpoint is reached (8 mg/L in this diagram). After breakpoint is achieved, additional chlorine finally results in a proportional accumulation of residual free available chlorine. 

Chlorine is also used in advanced wastewater treatment (AWT) for nitrogen removal, through a process known as breakpoint chlorination. For nitrogen removal, enough chlorine is added to the wastewater to convert all the ammonium nitrogen to nitrogen gas. To do this, about 10 mg/L of chlorine must be added per mg/L of ammonia nitrogen in the wastewater—about 40 or 50 times more chlorine than normally used in a wastewater plant for disinfection only. 

In breakpoint chlorination, about 10 mg/L of chlorine must be added for each mg/L of ammonia nitrogen present in the wastewater. Studies show that better pretreatment will... 

Usually, a base chemical is added to the breakpoint process to neutralize some of the acidity resulting from the chlorine addition. The base requirements depend on wastewater alkalinity, individual treatment processes used before breakpoint chlorination, as well as effluent pH or alkalinity restrictions by regulatory agencies. 

Borrow J, Goddard AD, Sheer D, Solomon E. Molecular analysis of acute promyelocytic leukemia breakpoint cluster region on chromosome 17. Science 1990 249 1577-80. 

A four-region adsorption isotherm for SDS. Slopes in regions I-IIf and transition points between regions are compared with results taken from literature. Solution concentrations at breakpoints reported in different publications are more consistent than corresponding adsorption densities. Uptake of preadsorbed dodecyisulfonate (10 mol dm ) at pH 3 is not influenced by addition of TX-lOO (up to 10 mol dm For 5x 10 mol dm dodecyisulfonate the uptake at pH 3 is enhanced in the presence of TX-100. The potential becomes less positive when TX-100 is added at constant dodecyl sulfonate concentration at pH < 8. 

Morgan JA, Yin Y, Borowsky AD et al (1999) Breakpoints of the t( 11 18)(q21 q21) in mucosa-associated lymphoid tissue (MALT) lymphoma lie within or near the previously undescribed gene MALT1 in chromosome 18. Cancer Res 59(24) 6205-6213... 

Schmitt C, Balogh B, Grundt A, Buchholtz C, Leo A, Benner A, Hensel M, Ho AD, Leo E. The bcl-2/IgH rearrangement in a population of 204 healthy individuals occurrence, age and gender distribution, breakpoints, and detection method validity. Leuk Res. 2006 30745-750. 

An FAC residual is regarded by the US Environmental Protection Agency as a sign of adequate disinfection. The problem encountered in ensuring that water leaving the treatment plant has been treated with enough chlorine to leave an FAC residual is illustrated by breakpoint chlorination. In breakpoint chlorination, dissolved chlorine is added to the water in a stepwise manner to determine the chlorine demand and to allow for the formation of chloramines. 

Initial waveforms are created within the system itself either by using a breakpoint function or by adding sinusoids, but sampled sounds may also be used. A great variety of instruments can be created by combining different waveforms and transition rules. 

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