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71.
This paper presents work directed at capturing the entrepreneurial and collaborative activity of university researchers. The Triple Helix points to the emergence of the entrepreneurial university as well as to an increasing overlay of activities in universities, industry and government. This study explores ways in which patent-based metrics could be utilized in a Triple Helix context, and how hybrid indicators could be developed by combining patent with survey data. More specifically, it aims to develop indicators that connect technological inventiveness of university researchers to both funding organizations and users, as well as to entrepreneurial activities by academics. The paper develops a simplified model of the innovation process to benchmark the relevance of the indicators to the Triple Helix. An analysis of Finnish academic patents illustrates that patent data can already provide useful indicators but, on its own, cannot provide information about how academic patents are interconnected with government or industry through funding or utilization links. An exclusive analysis of patents can point to patent concentrations on certain universities, to inventors and assignees, or to potential gaps in translating applied science into industrial technology. However, the patent data had to be combined with an inventor survey in order to relate academic patents more to their Triple Helix environment. The survey indicated that most patented academic inventions are connected to (often publicly funded) scientific research by the inventors and tend to be utilized in large firms rather than in start-up companies founded by academic entrepreneurs. 相似文献
72.
Content This paper is dealing with the power density versus electric field characteristic of microwave-excited discharges on the example of typical CO2 laser gas discharges.The fundamentals of the method are a simple electric equivalent circuit for the excitation structure and the assumption of a fixed reduced electric field intensity within the plasma. This operating field is enforced by the plasma under stationary conditions and can be calculated using an electron balance under consideration of the non-Maxwellian electron energy distribution function. The calculations turn out that c.w. excitation with microwaves is involved with considerable plasma power densities. In the case of the CO2 laser this requires special discharge channel designs for effective gas cooling. Besides a discussion of the plasma characteristic, measurements taken from a microwave applicator are presented and compared to the calculations.
Modellierung mikrowellenangeregter Gasentladungen
Übersicht Der Artikel behandelt die Berechnung der Feldstärke-Leistungsdichte-Kennlinie mikrowellenangeregter Gasentladungen am Beispiel von Entladungen in typischen CO2-Lasergasgemischen. Das Berechnungsverfahren beruht auf einem einfachen, auf die meisten Anregungsstrukturen anwendbaren elektrischen Ersatzschaltbild und der Tatsache einer vom Plasma erzwungenen stationären Brennfeldstärke. Letztere wird über eine Elektronenbilanz unter Berücksichtigung der nicht Maxwell'schen Elektronen-Energieverteilung ermittelt. Es zeigt sich, daß bei einer CW-Anregung mit Mikrowellen hohe Mindestleistungsdichten im Plasma auftreten, wodurch beispielsweise im Fall des CO2-Lasers kein Laserbetrieb ohne sehr effektive Maßnahmen zur Gaskühlung möglich ist.Neben einer Diskussion der Plasmakennlinie werden Vergleichsmessungen an einer konkreten Anregungsstruktur vorgestellt.相似文献
73.
The chromium content in foods is relatively low and the most foods have a content below 0.1 ppm. Only spices, cacao, cacao products, poppy and whole meal products contain higher contents. The often published high chromium content of corn germ oil could not be verified. We did not find any chromium enrichment in the entrails of a cow. In addition the chromium contents of each food are strong deviated. The analysed values were sometimes lower than in literature. We expect that the elder values are higher because of different contaminations in some cases. 相似文献
74.
Droplet formation on Si surfaces bombarded by 10 keV beams from a liquid metal indium ion source has been observed. It has been verified that excess indium is transported in the ion beam, probably in the form of charged droplets. SIMS, SEM and RBS techniques have been used to study the distribution of droplets at the surface. At the specified ion source operating conditions, equilibrium droplet coverage is of the order of 25%. Individual droplets have an average diameter of 0.35 ωm and an average height of 2.2 nm. At a bombardment current density of 0.1 mA cm?2, equilibrium coverage is reached in about 1 s. 相似文献
75.
C. Schönbauer Dipl.-Ing. 《e & i Elektrotechnik und Informationstechnik》2003,120(10):304-306
The new law for the support of electricity produced by renewable sources in Austria (Ökostromgesetz) which came into force with the beginning of 2003, shows its impacts already after the first months. Investments into wind power have increased considerably. These will be accompanied by activities for electricity production by biomass and biogas. The 4%-target quota will probably be reached earlier than the 2008 target period of the law. 相似文献
76.
The mechanism of the loss of stereospecificity in palladium-catalyzed nucleophilic substitution of allylic substrates has been investigated. Eight substrates (cis and trans isomers of 1a-d) and two nucleophiles (Et2NH and NaCH(SO2Ph)2) were studied. In the animation reactions two pathways are responsible for the formation of anomalous inversion product, viz., isomerization of the starting material (path B, Scheme 2) and isomerization of the π-allyl intermediate via displacement of palladium by Pd(0) (path C, Scheme 2), the latter of which predominates. In the alkylation the results indicate that loss of stereospecificity is caused only by path C. The use of a more reactive substrate increased the stereospecificity of the reaction and suppressed the isomerization pathway. An analysis of the kinetics is consistent with the hypothesis that path C is the major pathway for the stereochemical loss. 相似文献
77.
L. Juul Thomsen T. Sch fer J. M. Sonnergaard H. G. Kristensen 《Drug development and industrial pharmacy》1993,19(15):1867-1887
A melt pelletization process was investigated in an 8 litre laboratory scale high shear mixer using a formulation with paracetamol, glyceryl monostearate 40-50, and microcrystalline wax. The effects of jacket temperature, product temperature during massing, product load, massing time and impeller speed were investigated by means of factorially designed experiments. The maximum yield of pellets in the range of 500-1400μm was found to approx. 90%. For process conditions preventing deposition of moist mass, the process was found to be reproducible. Impeller speed and massing time were found to be important process variables. Remarkably low in vitro drug release rates were observed in USP-dissolution tests. 相似文献
78.
Kurzfassung Die Saltpool-Experimente von OSWALD (1998) und OSWALD & KINZELBACH (2004), im Jahre 1998 an der ETH Zürich ausgeführt, sind exzellente Benchmark-Tests für numerische Simulationsprogramme der dichtevariablen Strömung. Zahlreiche Autoren haben Ergebnisse dazu veröffentlicht. Die kritischen Probleme hierbei sind sowohl die zu dicke Übergangszone von hoher Konzentration an der Sohle der Versuchsbox zum Süßwasser am Top der Box in der Injektionsphase und in der Ruhephase als auch die extrem langen Rechenzeiten.Die Untersuchungen von HÄFNER & BOY (2003a) wurden fortgeführt mit dem erweiterten Code MODCALIF-MST (MODular Flow and CALIbration with Front Limitation algorithm—Multi Species and Temperature). Insbesondere werden Methoden zur Rechenzeitbeschleunigung diskutiert und verifiziert. Durch Nutzung eines algebraischen Multigrid- Gleichungslösers konnte die Rechenzeit um den Faktor 4 verringert werden. Zur Prüfung der Leistungsfähigkeit von MODCALIF-MST wurden die Saltpool Experimente, case 1 und case 2, nachsimuliert und Gitterkonvergenzstudien sowie eine Modellkalibrierung durchgeführt.
Simulation of density-dependent solute transport in groundwater and verification with saltpool experiments
Abstract The Saltpool experiments by OSWALD (1998) and OSWALD & KINZELBACH (2004), carried out in 1998 at the ETH Zurich, are an excellent benchmark test for numerical simulation programmes of the variable-density flow. Numerous authors published results on this subject. Here, critical problems are the thick transition zones from high concentration at the bottom to fresh water at the top of the box in the injection phase and the rest phase (phases 1–2) as well as the extremely long computing time.We have continued the investigations by HÄFNER & BOY (2003a) with the extended code MODCALIF-MST (MODular Flow and CALIbration with Front Limitation algorithm—Multi Species and Temperature) in double porosity porous media. Especially, the methods for code acceleration are discussed and verified. By incorporating the algebraic multigrid package as linear equation solver, computing times could be reduced by a factor of about 4. Simulations, a grid convergence study and a model calibration were carried out for the experiments case 1 and case 2 with MODCALIF.相似文献
79.
80.