Approaches to utilizing

Vinyl chloride is an important monomer for polyvinyl chloride (PVC). The main route for obtaining this monomer, however, is via ethylene (Chapter 7). A new approach to utilize ethane as an inexpensive chemical intermediate is to ammoxidize it to acetonitrile. The reaction takes place in presence of a cobalt-B-zeolite. 

In some situations, it makes good economic sense to tap the earth s heat as an energy source. One approach to utilizing this resource is illustrated in the sidebar on this page. 

It is known that in five of the six principal types of binary fluid phase equilibrium diagrams, data other than VLE may also be available for a particular binary (van Konynenburg and Scott, 1980). Thus, the entire database may also contain VL2E, VL E, VL]L2E, and L,L2E data. In this section, a systematic approach to utilize the entire phase equilibrium database is presented. The material is based on the work of Englezos et al. (1990b 1998)... 

Abdel-Aala, H.K., M. Sadika, M. Bassyounia, and M. Shalabib, A new approach to utilize hydrogen as a safe fuel, Int. ]. Hydrogen Energ., 30,1511-1514,2005. 

Wajima and coauthors offer an alternative approach to utilize animal VD data to predict human VD [13]. Several compound descriptors that included both chemical structural elements as well as animal VDSS values were subject to multiple linear regression and partial least squares statistical analyses, with human VDSS as the independent parameter to be predicted using a dataset of 64 drugs. Methods derived in this manner were compared to simple allometry for overall accuracy. Their analyses yielded the following regressions ... 

DiGiano, F.A., Frye, W.H., and Baxter, C.W. A rational approach to utilization of carbon beds in reducing microorganic contaminationindrinking water, Water Resources Research Center, University of Massachusetts, Amherst, MA, January 1980. 

Bernhardt, W., Konig, A., Lee, W. and Menard, H., Economic Approaches to Utilize Alcohol Fuels in Automobiles, Inter. Symposium on Alcohol Fuel Technology, Wolfsburg, Germany (Nov. 1977). 

Stabilization of a P-hairpin structure can be achieved in two ways, promoting a stable (or restricted) turn structure (as done with mimetics) or linking the two arms either chemically, or, more naturally, by hydrophobic interactions. In an approach to utilizing both methods, a D-Pro-Gly linkage was used to stabilize a left-handed turn (type I or II ) and various charged and hydrophobic residues were used to stabilize the molecule and enhance the interaction between arms. I252"254 Examples of these peptides studied in nonaqueous solution by IR, VCD and NMR spectroscopy exhibit characteristics of well-formed hairpins. 255 Alternatively, in aqueous solution, IR, VCD, and ECD results for related peptides agree with the NMR interpretation of conformations characterized as hairpins stabilized at the turn and frayed at the ends. 256 These latter results also have a qualitative match with theoretical simulations. Recently, examples of hydrophobically stabilized hairpins studied by NMR spectroscopy have avoided use of a nonnatural amino acid. 257,258 ... 

There are two fundamentally different approaches to utilizing mass transport relationships to determine electrode kinetics. By determining electrode kinetics , we mean elucidating the dependence of the rate of the electrode reaction on the variables that affect it. For the reaction... 

Photochemomechanical systems have also been studied using gels and photochemical reactions such as photochromism of spiropyrans [20], trans-ds transition of azobenzene [21] and photo-dissociation of triphenylmethane leuco cyanide [22]. It is an attractive approach to utilize a molecular level conformational change. 

Broadly, there are four acceptable approaches to utilization of hydrocarbonization char. If a low-sulfur char is produced, it may readily be used as a boiler fuel or as a feedstock for production of metallurgical coke. Alternatively, a high-sulfur char may be utilized as a boiler fuel either in a conventional furnace with flue gas desulfurization or in a fluidized-bed combustor. 

The direct extension of similar approaches to other systems, notably alkyl-cobalamins and related alkyl-cobalt compounds, is constrained by the instability of the corresponding hydrides, which are consequently unsuitable as radical traps. Modification of the approach to utilize other radical traps (e.g., 02) potentially is feasible but needs further investigation in view of possible complicating features such as reaction between the trapping agent and the parent metal-alkyl and ambiguities between homolytic dissociation and other (e.g., concerted) mechanisms (26, 27). 

Carbon dioxide (CO2), the natural product of fossil-fuel combustion, has been recognized as the main factor for the global warming. Among the various approaches to utilize the CO2 gas, there has been a considerable interest in biological CO2 fixation as a clean and energy-efficient technique [1]. 

As a first approach to utilizing this flashing index calculation technique, component flashing indexes were defined as the reciprocal of the component vapor pressure at the flash point. Mixture flash points were then computed by trial-and-error as the temperature at which... 

Homs and co-workers described the linkage of ethene and C02 on a supported platinum/tin complex yielding 3-hydroxypropionic acid [73], Another approach to utilizing C02 was pursued by Tominaga and Sasaki, namely hydroformylation with C02 [74]. 1-Hexene, for instance, reads with a mixture of C02 and H2 in the presence of ruthenium dusters giving heptanals, heptanols, and, in small amounts, the undesired hexane as a result of simple hydrogenation. Mechanistically it is assumed that a retro water gas shift reaction occurs, in which CO and H20 are formed from C02 and H2. This carbon monoxide undergoes ordinary hydroformylation with the alkene and H2. 

An essentially nonmathematical approach to utilizing the basic Hansch concepts to help design drugs was developed by Topliss (1977). It has been called a decision tree (Fig. 1-10), by which a lead compound can be efficiently optimized without the use of computers. By preparing several well-chosen analogs of a lead compound, the next several... 

Technologies Corporation MEAs. Alternate approaches to utilizing low platinum ioadings include a process where platinum is sputter-deposited on graphite and the electrode is pressed onto Nation . 

Another novel approach to utilizing affinity surfaces is referred to as the material-enhanced laser desorption/ionization (MELDI) technique [95] (Figure 3.10). This method was developed with the use of specially derivatized chromatographic materials (cellulose, silica, poly [glycidyl methacrylate/divinylbenzene] particles, and diamond powder) for fast and direct protein profiling to evaluate normal and pathological human serum samples. 

Biomass is one t5rpe of carbon-neutral, renewable energy source and has been considered for an attractive resource during the past few decades due to its abundance in the world. Microbial fuel cell (MFC) is one approach to utilize the abundant biomass, and it has the advantage of directly converting biomass into electricity with high columbic efficiency over traditional biomass utilization approaches, such as incineration, gasification, fermentation, etc. 

Price A, Bartley S, Male S, Cooley G (1999) A novel approach to utility scale energy storage. Power Eng J 13 122-129... 

Chiral smectic ferroelectric liquid crystals are liquids that possess spontaneous polar order. Combined with their excellent processibility on silicon integrated circuits, these liquid crystals provide an attractive potential approach to synthesis of materials for second order nonlinear optics, provided adequate second order susceptibility can be obtained. Unfortunately, the second-order nonlinear optical susceptibility of the ferroelectric liquid crystals are usually low and their thermal stability is limited. Several, very interesting approaches to utilization of liquid crystals, however, were carried out. 

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