Single synthesis

N-terminus For chemokines it is well-known that the N-terminal residues are critical for function (2-6,9). Sometimes the N-terminus of the mature protein is not known. Synthesis allows generation of multiple N-terminal forms in a single synthesis, thus allowing determination of the correct form. 

A new low investment process for the conversion of natural gas to gasoline is presented. The process incorporates the MTG process into a combined MeOH and dimethylether synthesis. The conversion of synthesis gas to gasoline is carried out in one single synthesis loop. The process has been demonstrated in a 1 MTPD gasoline process demonstration unit. 

Consequently, further development of the MTG process as it is realised in New Zealand should aim at a reduction of the investment. The TIGAS process represents such an effort. In the TIGAS process the two process steps, MeOH synthesis and the MTG process, are integrated into one single synthesis loop without isolation of MeOH as an intermediate (ref. 1), (Fig. 1). 

The purpose of the process development work on the integrated gasoline synthesis was to modify the three process steps, synthesis gas production, oxygenate synthesis and the MTG process, in order to be able to operate all steps at the same pressure and the last two steps in one single synthesis loop. 

Corey and associates (1970) worked out a stereospecific synthesis route for the preparation of juvenile hormone. The essential element of their method is the use of phosphonium-ylides for the stereospecific linkage of three structural units in a single synthesis step. 

Multiple reactor solid-phase synthesizers provide a high throughput of synthetic biopolymers. The same considerations as for a single synthesis should be applied to a multiple synthesis. The reaction kinetics and reagent requirements are generally quite similar. However, a synthesizer with many reactors often has some major design differences as compared with an instrument that contains only a few reactors. 

A major consideration with a multiple synthesizer is the speed and efficiency of delivery (and removal) of reagents. A 30-s wash step in a single synthesis may seem insignificant, but multiply that by 100 syntheses and the time for the wash step approaches 1 h. The delivery times are often reduced by lowering the scale of the individual syntheses and therefore the amount of reagent required or delivering simultaneously to multiple reactors. 

A conventional single synthesis system utilizes valves and tubing to route the flow of reagents to the reactor. As the number of reactors increases, it becomes impractical to have valves and tubing for each reactor. To eliminate the need for this added hardware, multiple synthesizers are often based on robotic designs, where the reactors remain stationary in a rack and one or more robotic arms transfer reagents to the individual reactors. The common steps can be expedited by simultaneous delivery to many reactors using... 

A comparison between thermal and microwave syntheses of colloidal silicalite-1 has provided a clear demonstration of the separate contributions of room-temperature ageing, heating rate and synthesis temperature to the nucleation process. At ageing times up to about 50 days, the product crystal size obtainable from a single synthesis composition is sensitive to reaction temperature and heating rate. After this time, ageing-generated proto-nuclei are so numerous that the normal self-nucleation of the reaction mixture is suppressed and the product crystal size is independent of reaction conditions. There is a limit to the number of crystals which can be nucleated and this is an intrinsic property of the system. 

The near-equality of cosmic and solar abundancies of the chemical elements points at either a single synthesis event, starting from elementary matter, or a common mechanism of nucleogenesis, wherever it happens. The first possibility is the one originally preferred in big-bang cosmology, but later abandoned as there was considered not to be enough time available for this process in the early universe. 

Comparison of the Environmental Balance of the Chemical and Bioctalytic Processes. The reason for the reduction in production costs is immediately apparent from the reaction sequence shown in Figure 111. Whereas the chemical process requires three intermediate stages, the biocatalytic process occurs in a single synthesis step in water at room temperature with ammonia addition for neutralization. 

The application domain and ASIC emulator architecture strongly influence the overall synthesis script as well as the actual algorithms for solving single synthesis tasks. In order to achieve efficient solutions, our whole approach has been tuned toward real-time system applications as they are found in mechatronic systems. To support the understanding of the implemented approach/algorithms, this section will describe the intended application domain and ASIC emulator architecture in more detail. 

A novel protocol for the synthesis of highly substituted pyridines in a single synthesis step by the microwave-assisted Michael addition-cyclodehydration of ethyl p-aminocrotonate, an alky none, has been developed by Bagley et al. (2002). This new one-pot Bohlmann-Rahtz procedure was conducted at 170°C in a self tunable microwave synthesizer giving high yield with total control of regiochemistry. 

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