Utilization phase

The design of this alloy was unique in that it utilized phase stability and other predictive techniques to balance the levels of critical elements (Cr, Mo, Co, Al, Wand Ta), thereby maintaining the hot corrosion resistance of IN-738 at higher strength levels without compromising phase stability. Most... 

Fig. 1.21 Echo Planar Imaging (EPI) pulse sequence. Gradient-echo based multiple echoes are used for fast single-shot 2D imaging. Slice selection along Gs and frequency encoding along C, are utilized. Phase encoding is realized using short blipped gradient pulses along Gp.

Adebiyi, G. A., 1991, A second law study on packed-bed energy storage systems utilizing phase change materials, ASME J. Solar Energy Eng. 113 146—156. 

The closely related Todd reaction, useful for the preparation of dialkyl phosphorochloridates and phosphoramidates, also involves the use of amines with dialkyl phosphites.146152 180-182 Although the reaction proceeds using preformed salts of the dialkyl phosphites,183 the use of tertiary amines facilitates the reaction by allowing all reagent materials to be in solution. Biphasic reaction systems utilizing phase-transfer catalysts and crown ethers have also been successful for this reaction.158-161... 

Phase separation (precipitation) of a polymer strongly depends on all its molecular characteristics. On the one hand, this allows very efficient separations in polymer HPLC utilizing phase separation and re-dissolution processes [20]. On the other hand, due to complexity of phase separation phenomena, the resulting retention volumes of complex polymers may simultaneously depend on several molecular characteristics of separated macromolecules. This may complicate interpretation of the separation results. Both precipitation and redissolution of most polymers is a slow process. It may be affected by the presence of otherwise inactive surface of the column packing. Therefore, the applicability and quantitative control of the phase separation phenomena may be limited to some specific systems of polymer HPLC. 

The most frequently used CSPs for biological applications in the reversed-phase mode are based on macrocyclic antibiotics, proteins, or oligosaccharides, but some of the applications utilize phases based on polysaccharides, low-molecular-weight selectors, crown ethers, or columns based on immunoaffinity techniques (Table 17.5). 

A detailed inspection of the coupling constants 3J5 6, and 3 J5 6 of several manno-sidic oligosaccharides utilizing phase sensitive COSY spectra has been reported [29]. The population analysis based on these coupling constants shows the preference of the gg conformation over gt while tg is not found within the precision of the analysis. 

It is often desired to have a device for a quality control of products with regard to emissions arising during the utilization phase. To enable action to be taken... 

The synthesis of quinolizidine (3-spiro-2 )-tetrahydrothiophene (67a, 67b), a model compound for the synthesis of dimeric sulfur alkaloids, was reported (65, 66). The compound was prepared from 2-cyanotetrahydrothiophene (66) by two independent routes, both utilizing phase-transfer catalysis (Scheme 10). 

The reaction of pyrrole with dichlorocarbene, generated from chloroform and strong base, gives a bicyclic intermediate which can be transformed into either 3-chloropyridine 192 or pyrrole-2-carbaldehyde 193. Indole gives a mixture of 3-chloroquinoline 194 and indole-3-carbaldehyde 195 the optimum conditions utilize phase transfer. Benzofuran reacts with dichlorocarbene in hexane solution to give the benzopyran 196, whereas benzothiophene fails to react. 

A mechanistic limitation of the Ritter reaction is that, while N-alkylformamides (and thence primary amines) are readily available, further direct substitution on nitrogen is mled out. However, simple A-al-kylation of the formamide may be performed utilizing phase-transfer catalysis. This provides a conven-... 

The majority of todays membranes used in microfiitration, dialysis or ultrafiltration and reverse osmosis cire prepared from a homogeneous polymer solution by a technique referred to as phase inversion. Phase inversion can be achieved by solvent evaporation, non-solvent precipitation and thermcd gelation. Phase separation processes can not only be applied to a large number of polymers but also to glasses and metal alloys and the proper selection of the various process parameters leads to different membranes with defined structures and mass transport properties. In this paper the fundamentals of membrane preparation by phase inversion processes and the effect of different preparation parameters on membrane structures and transport properties are discussed, and problems utilizing phase inversion techniques for a large scale production of membranes are specified. 

Opportunities and (in Particular) Risks of Use (Utilization Phase) of Plastic Structural Components... 

In this magnitude COSY experiment it is possible to obtain sine and cosine modulated data with co-addition using a simple two step phase cycle and consequently the minimum number of scans per increment is 2 or for long acquisitions a multiple of 2. The simplicity of this pulse program is in contrast to the phase sensitive COSY experiment and other Bruker two dimension pulse programs which utilize phase increment commands such as ipl to achieve frequency discrimination in fl. 

Segregated polymer brushes were fabricated utilizing phase-separation phenomena in ultrathin polymer blend films (PS-COOH/PMMA) and the combination of grafting-to and grafting-from methods. 

The dimensional stability of PCBs is highly complex in all three directions (x, y, and z) throughout both the production and utilization phases. 

Abstract The previous chapters have described the opportunities and risks of plastics as materials, whereas in this chapter and the chapters, Opportunities and Risks Involved in Designing Structural Components Made of Polymers, Plastics and Structural Components - The Environment and Recycling, they will be discussed in terms of the structural components made of plastics. The opportunities often predominate due to the advantages of plastics over other materials, for example metals, ceramics, and wood. To avoid repetition, this chapter will deal primarily with the risks of the utilization phase of plastic products. The specific applications used to illustrate this are listed in the keywords. 

Keywords Automotive interiors. Biodegradable plastics, Condoms, Designing structural components. Door handles. Fiber composites. Interior paneling elements. Joint endoprostheses. Kneading clay. Mats for office chairs (carpet protection). Packaging material. Parts in cars. Polycarbonate glasses, Pressboard, Rubber plates. Tires, Toys made of soft PVC, Utilization phase... 

To avoid repetition, this chapter will deal primarily with the risks of the utilization phase of plastic products. Before these risks are illustrated by specific applications in the following sections in the categories thermoplastics, duroplastics, and elastomers, below is a review of some of the general risks. 

These few examples show that all plastics release emissions in the form of more or less critically hazardous volatile organic components (VOCs) during the synthesis, compounding, and subsequent utilization phases (see above all Sect. 4 in chapter Properties of Plastics in Structural Components ). 

Residual amounts of some of these problematical substances remain in the product (low molecular components) and permeate to the outside during the utilization phase. Other processes (aging, degradation) continue throughout the hfecycle of the product beginning with new status. The aging rate, for example hydrolysis, depends on enviromnental conditions such as temperature, pressure, mediums, and time. 

A new general synthesis of primary and secondary amines utilizes phase-transfer-catalysed alkylation of diphenylphosphinic amide, which is readily available (Scheme 3), The alkylation step is limited to primary alkyl halides as alkylating agents, but the diphenylphosphinoyl protecting group is superior to the diethoxyphosphonyl group reported previously/... 

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