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991.
Helmut Schmidt 《Journal of Sol-Gel Science and Technology》2006,40(2-3):115-130
This paper was given on occasion of receiving the first Life Time Award by the International Society on Sol-Gel Science and
Technology. Its intention is to provide an insight on the development of this field, its driving forces and especially on
its impact on application and industrial technologies. The motivation of the work carried out in the last decades is that
in the early days of the sol-gel technologies, where this route started to interest industry as well as scientists, the author
got interested in a field which was clearly application-driven and strongly anchored in the material scientist community rather
than in fundamental chemistry. If one is talking about application-oriented technologies, of course, markets and industrial
needs have to be taken into consideration, because the restrictions or bottle-necks, but also chances provided by economical
needs strongly may govern the field. In opposition to these fields, only driven by science, may not have these restrictions
as far as it is possible to raise funds for the scientific work. For this reason, the attempt is made to point out the connections
between application and science in the sol-gel field. Since I am working in the sol-gel field since 1975, strongly focused
on industrial applications, it should be understandable that many of my own development examples are used to demonstrate this
way.
Another problem, of course, is connected to the sol-gel field: This is a question of appropriate definitions as well as to
draw a clear borderline of the field. Especially in the last decade, the connection of sol-gel materials to nanostructured
materials has become closer, so that it is difficult to clearly divide these fields. On the other hand, the fabrication of
nanoparticles by hydrolysis and condensation processes or controlled precipitation processes can be defined as a sol-gel technology,
but in many cases is just not done. This leads to the fact that in many areas, sol-gel types of processes are used, but called
different. Due to the fact that the properties of small particles either in solution or dispersed in an appropriate matrix
show highly interesting material properties, it would be desirable that the sol-gel community would try to interact stronger
with these developments (e.g. the “particle” community). This also might include a focus of the sol-gel area a little bit
more back to the routes, to material science development and engineering. According to my opinion, this would be a very interesting
supplement for the field as it is represented today. 相似文献
992.
PlasmidpCP1 was constructed from cloned 2 µmDNA ofSaccharomyces cerevisiae and from plasmidpJDB207. VectorpCP1 contains the completeB form of 2 µmDNA interrupted in theFLP gene, together withDNA derived from theEscherichia coli plasmidpAT153 and a low expression variant of theS. cerevisiae LEU2 gene. The new vector is lost at a low frequency from yeastcir
+ orcir
0 strains under non-selective growth conditions and is stable against rearrangements incir
0 strains. Its usefulness for curingcir
+ strains from endogenous 2 µmDNA and for their conversion tocir
0 strains was demonstrated.Dedicated to Professor Dr.Karl Schlögl on the occasion of his 60th birthday. 相似文献
993.
Arthur E. Jacobson Fu-Lian Hsu Maria D. Rozwadowska Helmut Schmidhammer Louise Atwell Arnold Brossi Fedor Medzihradsky 《Helvetica chimica acta》1981,64(5):1298-1302
The antinociceptive potency and receptor affinity of several optically active aromatic mono- and di-oxygenated N-methylmorphinans and N-methylmorphinan-6-ones, prepared from natural morphine, were determined. Thus, in order of antinociceptive potency, 4-methoxy-N-methylmorphinan-6-one ≈ 3,4-dimethoxy-N-methylmorphinan-6-one ≈ 3,4-dimethoxy-N-methylmorphinan > 4-methoxy-N-methylmorphinan ≈ 4-acetoxy-N-methylmorphinan-6-one > 4-acetoxy-N-methylmorphinan ≈ 4-hydroxy-N-methylmorphinan-6-one ≈ 4-hydroxy-N-methylmorphinan. The 4-hydroxy compounds were slightly less potent than morphine, and the 4-methoxy and 3,4-dimethoxy compounds were found to have three times the potency of morphine. 4-Methoxy-N-methylmorphinan-6-one showed an opiate receptor affinity one-third that of morphine; this is a remarkably high affinity for a non-phenolic compound. 相似文献
994.
995.
A. Hamy C. Otto Fr. L. Hahn K. Vieweg Helmut Meyer Fr. L. Hahn Helmut Meyer und J. E. Wynfield Rhodes 《Fresenius' Journal of Analytical Chemistry》1928,73(12):464-471
Ohne Zusammenfassung 相似文献
996.
We have examined the influence of parametric noise on the solution behavioru(t, x) of a nonlinear initial value() problem arising in cell kinetics. In terms of ensemble statistics, the eventual limiting solution mean
and variance
are well-characterized functions of the noise statistics, and
and
depend on . When noise is continuously present along the trajectory,
and
are independent of the noise statistics and . However, in their evolution toward
and
, both
u
(t, x) and
u
2
(t, x) depend on the noise and. 相似文献
997.
998.
Helmut Schmidhammer Karin Mayer-Valkanover Michaela Walla-Kugler 《Helvetica chimica acta》1990,73(7):1986-1990
Starting from 5-methyl-oxycodone ( 6 ), 5-methylnaloxone ( 4 ), and 5-methylnaltrexone ( 5 ) have been prepared in several steps. Both 4 and 5 behaved as partial agonists in the AcOH writhing agonism and antagonism test in mice. 相似文献
999.
In the last years, it has been shown that the formation and migration of system zones is an inherent feature of capillary zone electrophoresis (CZE) and that it depends predominantly on the composition of an actual background electrolyte (BGE). In most of the currently used BGEs, the SZs are invisible by the UV absorbance detection system, however, the comigration of SZs with the zones of analytes deteriorates the analytical performance of CZE and may be fatal for its utilization. Therefore, the theoretical predictions of the existence and migration of SZs is of key importance for the expediency of CZE. This is a review of the theoretical treatments of SZs which reveals the origin and the properties of SZs and shows how to cope with them. Also, a table of some typical BGEs is presented where the existence and mobilities of SZs are given. 相似文献
1000.
Anton Pachinger Elisabeth Eisner Claudia Tertsch Helmut Begutter Hubert Klus 《Journal of separation science》1992,15(5):302-304
A gas chromatographic method with alkali flame ionization detection is described for the determination of residue levels (0.1 μg/I and below) of deethylatrazine and deisopropylatrazine in drinking and ground water. Confirmation of the identities of the compounds is achieved by trifluoroacetylation, reaction conditions for which are presented. 相似文献