Clean Concepts

The critical micelle concentration (CMC) is the detergent concentration above which micelles form. Below the CMC, the detergent molecules are in monomer solution. The CMC depends on the temperature, the ion strength, the buffer pH, and the concentration of nonionic substances such as urea or alcohols. 

The cloud point is the temperature at which the detergent precipitates in watery solution. A number of further concepts that are less important to daily work—such as the critical micelle temperature, the Krafft point, and the hydrophile/lipophile equilibrium— are described in the overview article by Helenius and Simons (1975), which is the best piece of writing about detergents in spite of its age. 

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These same concepts could be used in fuel cell powered cars. Ultralight fuel cell vehicles are a part of the current generation of clean concept cars, sometimes called Green Cars. In 1996, when EV1 became available, it accelerated the development of the hybrid Toyota Prius and GM would show a number of alternative-fueled concept cars at the 1998 Detroit Show. Now every auto show has its alternative cars. 

These same concepts could be used in fuel cell powered cars. Ultralight fuel cell vehicles are a part of the current generation of clean concept cars, sometimes called Green Cars. 

The no-clean concept (i.e., no cleaning after soldering) proceeds from the following assumptions ... 

Clean Air Act of 1970 The Clean Air Act of 1970 was founded on the concept of attaining National Ambient Air Quahty Standards (NAAQS). Data were accumulated and analyzed to establish the quality of the air, identify sources of pollution, determine how pollutants disperse and interac t in the ambient air, and define reduc tions and controls necessary to achieve air-quahty objectives. 

Bubble Policy The bubble concept introduced under PSD provisions of the Clean Air Act Amendments of 1977 was formally proposed as EPA policy on Jan. 18, 1979, the final policy statement being issued on Dec. 11, 1979. The bubble pohcy allows a company to find the most efficient way to control a plant s emissions as a whole rather than by meeting individual point-source requirements. If it is found less expensive to tighten control of a pollutant at one point and relax controls at another, this woiild be possible as long as the total pollution from the plant woiild not exceed the sum of the current hmits on individual point sources of pollution in the plant. Properly apphed, this approach would promote greater economic efficiency and increased technological innovation. 

You should strictly follow correct and acceptable practices w hen removing the old bearing and installing the new one. Cleanliness is the order of the day. You ll need a clean work area, clean hands, and cleaning cloths without fuzz, lint, or strings. So much of premature hearing failure is the direct result of not observing these basic concepts. 

It may be desirable to curtail transport of pollution to areas whose air is presently quite clean, even though, after such transport, the air quality of the area would be considerably cleaner than would be required by air quality standards. This concept is called prevention of significant deterioration of the air quality in such areas. It requires definition of how much deterioration can be considered insignificant. 

The future of Cl engines will be significantly influenced by the efforts to develop clean diesel concepts. In the context of heavy-duty diesel engines, increasing... 

Comparisons of heat-release rates and combustion photographs obtained in the HSCI engine (conventional) and Premixed Cl engine (MK). (From Kimura, S., Aoki, O., Kitahara, Y., and Aiyoshizawa, E., Ultra-Clean Combustion Technology Combining a Low-Temperature and Premixed Combustion Concept for Meeting Future Emissions Standards, SAE, 2001-01-0200,2001. With permission.)... 

Kimura, S., Aoki, O., Ogawa, H., Muranaka, S., and Enomoto, Y, New Combustion Concept for Ultra-Clean High-Efficiency Small Dl Diesel Engines, SAE, 1999-01-3681,1999. 

Ultrasound can thus be used to enhance kinetics, flow, and mass and heat transfer. The overall results are that organic synthetic reactions show increased rate (sometimes even from hours to minutes, up to 25 times faster), and/or increased yield (tens of percentages, sometimes even starting from 0% yield in nonsonicated conditions). In multiphase systems, gas-liquid and solid-liquid mass transfer has been observed to increase by 5- and 20-fold, respectively [35]. Membrane fluxes have been enhanced by up to a factor of 8 [56]. Despite these results, use of acoustics, and ultrasound in particular, in chemical industry is mainly limited to the fields of cleaning and decontamination [55]. One of the main barriers to industrial application of sonochemical processes is control and scale-up of ultrasound concepts into operable processes. Therefore, a better understanding is required of the relation between a cavitation coUapse and chemical reactivity, as weU as a better understanding and reproducibility of the influence of various design and operational parameters on the cavitation process. Also, rehable mathematical models and scale-up procedures need to be developed [35, 54, 55]. 

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