Water injection systems surface area

Fig. 10. Zonation of the Larderello geothermal field derived from (a) gas analyses, and (b) stable isotope values of steam produced before and after re-injection. Distribution and characterization of geothermal subunits obtained by gas analyses have been established from a data set collected before 1989, that is, 6 years after the beginning of re-injection of waste waters. White zones represent areas that produce gas mixtures with almost the same composition as that of the original gases emerging at the surface before the exploitation of the field (Scandiffio et al. 1995). Dashed zones produce steam affected by addition of cold water (i.e., re-injected) to the geothermal system. The zonation from the isotopes was derived from an extensive survey performed in 1992. In Fig. 10b, different sources of cold water are discriminated. Abbreviations LRD = Larderello, CN = Castelnuovo, MR = Monterotondo, SS = Sasso Pisano, LGR = Lagoni Rossi, SR = Serrazzano geothermal subunits.

Volcanic injection of large quantities of sulfate aerosol into the stratosphere offers the opportunity to examine the sensitivity of ozone depletion and species concentrations to a major perturbation in aerosol surface area (Hofmann and Solomon 1989 Johnston et al. 1992 Prather 1992 Mills et al. 1993). The increase in stratospheric aerosol surface area resulting from a major volcanic eruption can lead to profound effects on C10 -induced ozone depletion chemistry. Because the heterogeneous reaction of N205 and water on the surface of stratospheric aerosols effectively removes N02 from the active reaction system, less N02 is available to react with CIO to form the reservoir species C10N02. As a result, more CIO is present in active CIO cycles. Therefore an increase in stratospheric aerosol surface area, as from a volcanic eruption, can serve to make the chlorine present more effective at ozone depletion, even if no increases in chlorine are occurring. 

This system incorporates rearward venting, stranding of the meit at the iniet to increase surface area, variabie gap before the section vent port by axiai screw adjustment, water injection, and bypass venting at the finai vent port. Such a system can reduce the monomer ievei from 15% down to as low as 0.1% in one operation. Such devolatilization performance is quite comparable to that of twin screw devolatilization systems. 

When microorganisms are involved in the corrosion of metals, the situation is more complicated than for an abiotic environment, because microorganisms not only modify the near-surface environmental chemistry via microbial metabolism but also may interfere with the electrochemical processes occurring at the metal-environment interface. Many industrial systems are likely to contain various structures where MIC and biofouling may cause serious problems open or closed cooling systems, water injection lines, storage tanks, residual water treatment systems, filtration systems, different types of pipes, reverse osmosis membranes, potable water distribution systems and most areas where water can stagnate. 

High-performance liquid chromatography (HPLC)-grade chloroform and methanol were obtained from Fisher Scientific Co. Peptide lipid library samples were dissolved in a mixed solvent of chloroform, methanol and CF3COOH (5 1 0.01, v/v/v) to a concentration of 1.0 mM. The injected volume was 40 )u-L for all samples. After spreading the sample, the solvent was allowed to evaporate for 15 min. The water used for the monolayer study was purified by a Modulab 2020 water purification system (Continental Water Systems Corp., San Antonio, TX). The water had a resistance of 18 MH cm and a surface tension of 72.6 mN/m at 20°C. The D-maltose, d-glucose, and sucrose used for subphase preparation were pmchased from Aldrich Chemical Co. and were dissolved in deionized water to a concentration of 10 mM. All these subphases had a pH of 5.8. The compression rate was set at 4 A molecule min for the smface pressme-area isotherm measmements. 

Therefore, the following method was suggested and realized (the scheme is shown in Fig. 17). A 1.5 M solution of KCl or NaCl (the effect of preventing BR solubility of these salts is practically the same) was used as a subphase. A platinum electrode was placed in the subphase. A flat metal electrode, with an area of about 70% of the open barriered area, was placed about 1.5-2 mm above the subphase surface. A positive potential of +50 -60 V was applied to this electrode with respect to the platinum one. Then BR solution was injected with a syringe into the water subphase in dark conditions. The system was left in the same conditions for electric field-induced self-assembly of the membrane fragments for 1 hour. After this, the monolayer was compressed to 25 mN/m surface pressure and transferred onto the substrate (porous membrane). The residual salt was washed with water. The water was removed with a nitrogen jet. 

Assume you work with water as the solvent for your sample. If you obtain different peak areas although you inject a constant amount of sample, the reason for this could be a partly irreversible adsorption of your solutes on a rough surface in the HPLC system ( hungry surfaces ). 

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