Chemical enhancers, enhancement

Micellar/polymer (MP) chemical enhanced oil recovery systems have demonstrated the greatest potential of all of the recovery systems under study (170) and equivalent oil recovery for mahogany and first-intent petroleum sulfonates has been shown (171). Many somewhat different sulfonate, ie, slug, formulations, slug sizes (pore volumes), and recovery design systems were employed. Most of these field tests were deemed technically successful, but uneconomical based on prevailing oil market prices (172,173). 

The Duoplasmatron (Eig. 3.18). In the Duoplasmatron, gas-discharge ion sources are used for bombardment with oxygen or argon. In dynamic SIMS, especially, the use of O2 ions is common because of the chemical enhancement effect. With a duoplasmatron ion beam currents of several microamps can be generated. The diameter of the beam can be focused down to 0.5 pm. 

The element sensitivity is determined by the ionization probability of the sputtered atoms. This probability is influenced by the chemical state of the surface. As mentioned above, Cs" or OJ ions are used for sample bombardment in dynamic SIMS, because they the increase ionization probability. This is the so-called chemical enhancement effect. 

The oxygen ion beam diameter is limited to 0.5 pm by the duoplasmatron source used. For mapping electropositive elements this drawback must be tolerated because of the chemical enhancement effect. 

A typical UF pilot plant has been used in this study. Examples of application for these membranes can be found in the literature [40, 58]. The UF unit woks in deadend mode (2.5 m h ) and it can be operated in filtration, backwash and chemically enhanced backwash (CEB) modes as described in the literature for similar UF systems [40]. The specifications of the hollow fiber UF modules and the operating conditions are summarized in Table 5. 

Chemically enhanced drilling offers substantial advantages over conventional methods in carbonate reservoirs. Coiled tubing provides the perfect conduit for chemical fluids that can accelerate the drilling process and provide stimulation while drilling [1471]. The nature of the chemical fluids is mainly acid that dissolves or disintegrates the carbonate rock. 

Xanthan exhibits an interaction with anionic surfactants (petroleum sulfate), which is a beneficial synergistic effect for mobility control in chemical-enhanced oil-recovery processes [1115]. 

A chemical-enhanced oil-recovery technology can be used to remove oily contaminants from soil. Laboratory studies demonstrated that a variety of alkaline-surfactant combinations can be used with a polymer to reduce the residual oil saturation in waterflooding [1435]. 

In heavy oil reservoirs with highly porous sands, cyclic steamflooding may cause the formation of stable emulsions. These emulsions can block the production paths in the wellbore. In steam cycle treatments, a blend of oxy-alkylated alkanolamines and sulfonates showed a dramatic improvement over non-chemically enhanced steam cycles [331]. 

M. J. Pitts, K. Wyatt, T. C. Sale, and K. R. Piontek. Utilization of chemical-enhanced oil recovery technology to remove hazardous oily waste from alluvium. In Proceedings Volume, pages 33-44. SPE Oilfield Chem Int Symp (New Orleans, LA, 3/2-3/5), 1993. 

R. Rae and G. Di Lullo. Chemically-enhanced drilling with coiled tubing in carbonate reservoirs. In Proceedings Volume. SPE/Int Coiled Tubing Assoc Coiled Tubing Roundtable (Houston, TX, 311-318), 2001. 

In the third region of coverage, most of the atomic scale roughness has been proposed to be irreversibly destroyed as the Pb layer rearranges to assume the final hexagonal close packed configuration of the monolayer.( ) This loss of atomic scale roughness results in the irreversible decrease in i/(0H) intensity to essentially unmeasurable levels. This observation further emphasizes the importance of the chemical enhancement mechanism contribution to SERS in electrochemical systems. 

Micellar flooding, 13 628 Micellar-polymer (MP) chemical enhanced oil recovery systems, 23 531 Micellar-polymer enhanced oil recovery (EOR), 16 429... 

Wilson, J. L., 1997, Removal of Aqueous Phase Dissolved Contamination Non-Chemically Enhanced Pump-and-Treat In Subsurface Restoration (edited by C. H. Ward, J. A. Cherry, and M. R. Scalf), Ann Arbor Press, Chelsea, MI, pp. 271-285. 

Sale, T. and Pitts, M., 1989, Chemically Enhanced in Situ Soil Washing In Proceedings of the National Water Well Association and American Petroleum Institute Conference on Petroleum Plydrocarbons and Organic Chemicals in Groundwater Prevention, Detection and Restoration, November, pp. 487-503. 

Hatch GG, Mamay PD, Ayer ML, et al. 1983. Chemical enhancement of viral transformation in Syrian hamster embryo cells by gaseous and volatile chlorinated methanes and ethanes. Cancer Res 43 1945-1950. 

Boundary layer models take a similar approach but attempt to extend the parameterization of gas exchange to individual micrometeorological processes including transfer of heat (solar radiation effects including the cool skin), momentum (friction, waves, bubble injection, current shear), and other effects such as rainfall and chemical enhancements arising from reaction with water. 

Chemical enhancers have been demonstrated to produce transport windows in eolonie epithelia large enough for the passage of many bacterial toxins. Patients suffering from inflammatory bowel diseases and colitis typically have increased colonic permeability [45] due to bacterial toxins, both entertoxins and cytotoxins that increase eapillary permeability. Increased colon permeability associated with a diseased state may be useful in treatment where improvement of the condition might reduce mucosal permeability and naturally reduce drug transport. 

Emerson S. 1975. Chemically enhanced CO2 gas exchange in a eutrophic lake a general model. Limnology and Oceanography 20 743-753. 

The variation of efficiencies is due to interaction phenomena caused by the simultaneous diffusional transport of several components. From a fundamental point of view one should therefore take these interaction phenomena explicitly into account in the description of the elementary processes (i.e. mass and heat transfer with chemical reaction). In literature this approach has been used within the non-equilibrium stage model (Sivasubramanian and Boston, 1990). Sawistowski (1983) and Sawistowski and Pilavakis (1979) have developed a model describing reactive distillation in a packed column. Their model incorporates a simple representation of the prevailing mass and heat transfer processes supplemented with a rate equation for chemical reaction, allowing chemical enhancement of mass transfer. They assumed elementary reaction kinetics, equal binary diffusion coefficients and equal molar latent heat of evaporation for each component. 

In section IID, we introduced the utilization of chemical enhancement effect for higher sensitivity in TERS. Here, it should be pointed out that in addition to electromagnetic enhancement and chemical enhancement effects, physical deformation induced by tip-applied force showed extra enhancement effect in TERS on carbon materials such as SWNTs and fullerene molecules (Yano et al. 2005, 2006 Verma et al. 2006). This tip-pressurized effect is a unique feature of TERS and not observable in SERS. Since the spatial resolution of TERS with tip-pressurized effect is determined by the size of the very end of the metallic tip that has direct contact with the molecules, this is a very promising approach to improve the spatial resolution of the near-field microscope. 

T0213 Duke Engineering Services, Inc., Chemically Enhanced Solubilization for Aquifer Remediation (CESAR)... 

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