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Recent and Future Developments

Increasing analysis speed for complex profiles without impairing resolution can only be realized by reduction of the internal diameter and the length of the capillary column. A lOmxO.l mm i.d. column offers the same resolution as a 25 m X 0.25 mm i.d. column. Because the column is 2.5 limes shorter, the analysis time is reduced drastically. Moreover, since the optimum carrier gas velocity is higher and the H-u curves are flatter for narrow bore columns, higher average carrier gas velocities can be used without loss of resolution. Presently, capillary columns with internal diameters in the order of 100 pm are in the picture for routine operation because state-of-the art cap- [Pg.254]

Injection split, 1 pL, 1/50 split ratio, 250 split, 1 pL, 1/500 split ratio, 250 C [Pg.255]

Carrier pressure 209 kPa. constant pressure 411 kPa. constant pressure [Pg.255]

The analysis was first performed on a standard column used for detailed essential oil profiling (60 m X 0.25 mm i.d. x 1 pm MeSi). The operational conditions optimized for routine QC were applied. Secondly, the analyses were repeated on a 20mx0.1mm i.d.x0.4pm MeSi. The operational conditions for the narrow bore column were calculated by using the method translation software. The most important operational conditions are summarized in Table 6. From the method translation software program, a speed gain factor of 5.9 is predicted. Note that the carrier gas in the analyses are helium and hydrogen for the 0.25 mm i.d. and the 0.1 mm i.d. columns, respectively. [Pg.255]

Recent developments in capillary GC, i.e., electronic pneumatic control (EPC) of the carrier gas, improved oven temperature stability, and excellent reproducibility in column making have led to the concept of retention time locking (RTL) [77], [78]. With retention time locked data bases, absolute retention times instead of retention indices can be used to elucidate the structures of eluting solutes. Moreover, retention time locking can be u.sed in combination with different injectors and detectors. Exact scaling of capillary GC-FID, capillary GC-MS, and capillary GC-AED chromatograms is feasible. [Pg.255]

The GRIND descriptors are insensitive to the chirality of the structures. This has the undesirable side effect of providing exactly the same description for the two enantiomers associated with any chiral center. Diastereomers might, on the contrary, produce different correlograms, due to the presence of differences in the internal geometry. [Pg.139]


The recent and future development of sulfur supplies in the Middle East tends to emphasize the resulting regional concept for sulfur supply/demand. However, as in North America, the rising production of involuntary sulfur has caused a drop in the amount of native pyrite sulfur produced. Table 2 shows recent past and estimated trends in several Middle Eastern countries. The future of by-product sulfur from oil and gas operations is very uncertain at the time of this writing (October 1980) because of the Iran-Iraq war and its effect on near-by countries. [Pg.229]

Recent and Future Developments, 192 6.1 Web Site Addresses and Recommended Reading, 194... [Pg.168]

Schoenmakers, PJ. and L.G.M. Uunk. 1987. Supercritical fluid chromatography — recent and future developments. Eur. Chromatogr. News 1 14—22. [Pg.113]

Recent and future developments of liquid chromatography in pesticide trace analysis Hogendoorn, E. Van Zoonen, P. J. Chromatogr., A 2000, 892, 435-453. [Pg.77]

The chemistry of NHC and of complexes bearing NHC continues to fascinate and surprise. The synthesis of abnormal coordinated carbenes (C5 coordination) in a process explored for more than 8 years is just one example that encourages chemists to examine closely the exact nature of active species involved in catalytic cycles. There is no doubt that recent and future developments in this field of chemistry will separate NHC ligands from the phosphine mimic label placed on them at the early development stages and will confer on them a distinct role in modern catalytic chemistry [102]. [Pg.273]

A good example of the recent and future evolution of viral vaccines and their concomitant issues of technology, complexity and competition, is the rotavirus vaccine. This is of great relevance for the prevention of diarrhea, which is often deadly in developing countries (half a million deaths per year) and has high hospitalization costs in rich countries. After successive failures of monovalent vaccines, multivalent vaccines based on the reshuffling of rotavirus strains comprising the attenuation properties of animal strains with the external capsid of human serotypes were developed. [Pg.454]

Future progress may, however, be accelerated by recent and forthcoming developments. Recent flash photolysis studies of metal-carbonyls and metal-metal bonded systems should provide a foundation for more extensive development of this area. Applications of picosecond and nanosecond flash systems to a wide variety of problems is expected. Such techniques should be... [Pg.291]

SECOND Recent and future material developments for RIM processable systems. [Pg.3]

The different modes of electron microscopy summarized in Fig. 2 have inherent prospects and limitations as will be discussed in this paper. First we will discuss these limitations and then introduce the use of 3D-TEM, in particular electron tomography, for the study of molecular sieves (section 2). The use of electron tomography in materials science is quite recent and exciting information on zeolites and mesoporous materials has already been obtained. These case studies will be dealt with in section 3. New and future developments are summarized in section 4. [Pg.227]

Keywords Concrete-polymer composites. Polymer-modified concrete. Polymer concrete. Polymer-impregnated concrete. Principles of process technology. Research and development. Standardization work. Sustainable concrete-polymer composites. History, The recent and future trends. [Pg.2]

The specific fields of recent and future applications of rapid flow-through chip PCR demand the development of PCR-based chip devices with additional integrated functions for sample pretreatment, on-line sensing, process control and real-time measurement, referencing, and reproducibility tests. Therefore, further efforts for integration of transducers as well as additional fluid manipulation functions are required. [Pg.2691]


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