Employers of choice

Australasian Railway Association (ARA), Department of Education, Employment and Workplace Relations (DEEWR). 2007a. The Changing Face cfRail A Journey to the Employer of Choice. Canberra, Australia ARA/DEEWR. 

Not so for synthesis in the chemical industry where a compound must be prepared not only on a large scale but at low cost There is a pronounced bias toward reactants and reagents that are both abundant and inexpensive The oxidizing agent of choice for example in the chemical industry is O2 and extensive research has been devoted to develop mg catalysts for preparing various compounds by air oxidation of readily available starting materials To illustrate air and ethylene are the reactants for the industrial preparation of both acetaldehyde and ethylene oxide Which of the two products is ob tamed depends on the catalyst employed... 

Instrumentation wires contain multiple pairs of conductors, each insulated with dame-retardant PVC and with an overall dame-retardant PVC jacket (5). Eor distribution wires polyethylene or ethylene—propylene mbber are the polymers of choice (Eig. 2c). A typical design for aerial self-supportingwires that employs PE and PVC, is shown in Eigure 2d. 

Microbial-enhanced oil recovery involves injection of carefully chosen microbes. Subsequent injection of a nutrient is sometimes employed to promote bacterial growth. Molasses is the nutrient of choice owing to its low (ca 100/t) cost. The main nutrient source for the microbes is often the cmde oil in the reservoir. A rapidly growing microbe population can reduce the permeabiHty of thief zones improving volumetric sweep efficiency. Microbes, particularly species of Clostridium and Bacillus, have also been used to produce surfactants, alcohols, solvents, and gases in situ (270). These chemicals improve waterflood oil displacement efficiency (see also Bioremediation (Supplement)). 

Multidimensional or hyphenated instmments employ two or more analytical instmmental techniques, either sequentially, or in parallel. Hence, one can have multidimensional separations, eg, hplc/gc, identifications, ms/ms, or separations/identifications, such as gc/ms (see CHROMATOGRAPHY Mass spectrometry). The purpose of interfacing two or more analytical instmments is to increase the analytical information while reducing data acquisition time. For example, in tandem-mass spectrometry (ms/ms) (17,18), the first mass spectrometer appHes soft ionization to separate the mixture of choice into molecular ions the second mass spectrometer obtains the mass spectmm of each ion. 

Because of the simplicity and reUabiUty of the Rankine cycle, faciUties employing this method have dominated the power industry in the twentieth century and typically play an important role in most modem combined-cycle faciUties. Water is the working fluid of choice in nearly all Rankine cycle power plants because water is nontoxic, abundant, and low cost. 

Economics vary, depending onlocation and country. In Japan, for example, the quinone of choice is the disodium salt of l,4-dihydto-9,10-dihydtoxyanthtacene (DDA). Unlike AQ, DDA is direcdy soluble in white Hquor and thus readily penetrates the chip. AQ works well with both hardwoods and softwoods. Addition rates as low as 0.025% by weight give satisfactory increases (ca 1—2%) in pulping rate and yield, especially for hardwoods. In the United States in 1987, the FDA put a limitation to the amount of AQ that can be added to most pulp to 0.11%. This typically is the amount added to softwoods lesser amounts ate employed with hardwoods. 

Bismuth compounds were once employed for the treatment of amoebic dysentery, certain skin diseases, and several spirochetal diseases besides syphilis, but these substances are now seldom considered the dmgs of choice. Various insoluble preparations of bismuth, especially the subcarbonate, subnitrate, subgaHate, subcitrate, and subsahcylate, are stiU employed for the treatment of ulcers and other gastrointestinal disorders, even though use for these purposes is often supported largely by tradition. With a few possible exceptions, it is now difficult to justify the presence of bismuth compounds in a modem therapeutic armamentarium. A review of the biological activity of organobismuth compounds has been pubHshed (179). 

Adhesion of paints and adhesives to TPOs is especially problematical due to the aliphatic nature of the substrate material. In Europe, plasma and corona treatment is employed to render these surfaces wettable and obtain strong adhesion by adhesives and paints in automotive manufacture. In the United States, however, primers based on solvent-borne chlorinated polyolefin oligomers (CPOs) have become the treatment of choice for these substrate materials. The VOC emissions from these primers are considerable (as in all solvent-borne adhesives), but the less... 

For the preparation of 19-nor-B-homosteroids Tadanier s acetolysis procedure appears to be the method of choice. The mild reaction conditions employed with each of these procedures allows the maintainance of a variety of functional groups, e.g., double bonds, ethers, hydroxyls and the like during the homologation process. 

A problem with employment of ASON in a larger clinical setting is their poor uptake and inappropriate intracellular compartmentalization, e.g., sequestration in endosomal or lysosomal complexes. In addition, there is a need for a very careful selection of the ASON-mRNA pair sequences that would most efficiently hybridize. To date, several computer programs are used to predict the secondary and tertiary structures of the target mRNA and, in turn, which of the mRNA sequences are most accessible to the ASON. However, even with this sophisticated techniques, the choice of base-pairing partners still usually includes a component of empiricism. Despite these principal limitations, it has become clear that ASON can penetrate into cells and mediate their specific inhibitory effect of the protein synthesis in various circumstances. 

If small or medium libraries for lead optimization are demanded and all synthetic products are to be screened individually, most often parallel synthesis is the method of choice. Parallel syntheses can be conducted in solution, on solid phase, with polymer-assisted solution phase syntheses or with a combination of several of these methods. Preferably, parallel syntheses are automated, either employing integrated synthesis robots or by automation of single steps such as washing, isolation, or identification. The latter concept often allows a more flexible and less expensive automation of parallel synthesis. 

For on-bead analysis vibrational spectroscopy (IR-spectroscopy) can be employed attenuated total reflection is a method allowing fast and nondestructive on-bead analysis of small samples (single bead analysis) without significant sample preparation. Solid phase NMR is the method of choice if complex structural analysis is intended on the support. Spatially resolved analysis on the resin is possible with microscopic techniques. 

Boilers are heat-transfer devices, wherein water, in the form of either liquid water or gaseous steam, is commonly employed as a medium for the transport of heat to some distant point of use. Although other heat-transfer mediums are sometimes utilized, water is particularly suitable because of its relative abundance, low cost, and high heat capacity. It is generally the medium of choice in most boiler applications, whether for domestic, commercial, institutional, or industrial purposes. 

Hydrogen peroxide was used to oxidize sulphoxides to sulphones at an early stage in the development of organosulphur chemistry28 and has remained the reagent of choice for everyday laboratory oxidations of this type. Typically, an excess of 30% hydrogen peroxide in water is employed at room temperature, often with a co-solvent such as an alcohol or acetone. 

Due to its broad scope, as well as to its favorable features (commercial availability of the catalyst, use of a "green" oxidant, economy, extremely simple procedure and work-up), this method has been rapidly accepted, as demonstrated by its use by several different research groups, despite its recent disclosure.1617 This procedure employing CH3Re03 and UHP appears to be the method of choice when optically active nitrones are prepared by oxidation of the corresponding amines.14 15 18... 

In many cases, these cyclic siloxanes have to be removed from the system by distillation or fractionation, in order to obtain pure products. On the other hand, cyclic siloxanes where n = 3 and n = 4 are the two most important monomers used in the commercial production of various siloxane polymers or oligomers via the so-called equilibration or redistribution reactions which will be discussed in detail in Sect. 2.4. Therefore, in modern silicone technology, aqueous hydrolysis of chloro-silanes is usually employed for the preparation of cyclic siloxane monomers 122> more than for the direct synthesis of the (Si—X) functional oligomers. Equilibration reactions are the method of choice for the synthesis of functionally terminated siloxane oligomers. 

In this chapter, DKRs will be categorized according to the racemization method employed, as being catalyzed by (i) a metal, (ii) a base, (hi) an acid, (iv) an aldehyde, or (v) an enzyme. Also racemizations that take place through continuous cleavage/ formation of the substrate, or through 5 2 displacement, among other methods, will be discussed. In most cases, the racemization method of choice depends on the structure of the substrate. In all cases, the KR is catalyzed by an enzyme. 

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