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排序方式: 共有797条查询结果,搜索用时 31 毫秒
1.
JOSEF MÁLEK JINDŘICH NEČAS K. R. RAJAGOPAL 《Archive for Rational Mechanics and Analysis》2002,165(3):243-269
To describe the flows of fluids over a wide range of pressures, it is necessary to take into account the fact that the viscosity
of the fluid depends on the pressure. That the viscosity depends on the pressure has been verified by numerous careful experiments.
While the existence of solutions local-in-time to the equations governing the flows of such fluids are available for small,
special data and rather unrealistic dependence of the viscosity on the pressure, no global existence results are in place.
Our interest here is to establish the existence of weak solutions for spatially periodic three-dimensional flows that are
global in time, for a large class of physically meaningful viscosity-pressure relationships.
(Accepted May 1, 2002) Published online November 15, 2002
Communicated by S. S. ANTMAN 相似文献
2.
Soderstrom E McKenna JA Abrams GS Adolphsen CE Averill D Ballam J Barish BC Barklow T Barnett BA Bartelt J Bethke S Blockus D Bonvicini G Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan DE Dorfan JM Drewer DC Elia R Feldman GJ Fernandes D Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Grindhammer G Grosse-Wiesmann P Hanson G Harr R 《Physical review letters》1990,64(25):2980-2983
3.
Komamiya S Abrams GS Adolphsen CE Averill D Ballam J Barish BC Barklow T Barnett BA Bartelt J Bethke S Blockus D Bonvicini G Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan DE Dorfan JM Drewer DC Elia R Feldman GJ Fernandes D Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gatto C Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Grindhammer G Grosse-Wiesmann P Hanson G Harr R 《Physical review letters》1990,64(24):2881-2884
4.
Wagner SR Hinshaw DA Ong RA Snyder A Abrams G Adolphsen CE Akerlof C Alexander JP Alvarez M Amidei D Baden AR Ballam J Barish BC Barklow T Barnett BA Bartelt J Blockus D Bonvicini G Boyarski A Boyer J Brabson B Breakstone A Brom JM Bulos F Burchat PR Burke DL Butler F Calvino F Cence RJ Chapman J Cords D Coupal DP DeStaebler HC Dorfan DE Dorfan JM Drell PS Feldman GJ Fernandez E Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gidal G Gladney L Glanzman T Gold MS Goldhaber G Green A 《Physical review letters》1990,64(10):1095-1098
5.
Weir AJ Klein SR Abrams G Adolphsen CE Akerlof C Alexander JP Alvarez M Amidei D Baden AR Ballam J Barish BC Barklow T Barnett BA Bartelt J Blockus D Bonvicini G Boyarski A Boyer J Brabson B Breakstone A Brom JM Bulos F Burchat PR Burke DL Butler F Calvino F Cence RJ Chapman J Cords D Coupal DP DeStaebler HC Dorfan DE Dorfan JM Drell PS Feldman GJ Fernandez E Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gidal G Gladney L Glanzman T Gold MS Goldhaber G Green A Grosse-Wiesmann P Haggerty J 《Physical review D: Particles and fields》1990,41(5):1384-1388
6.
7.
W. Bell K. Braune G. Claesson D. Drijard M. A. Faessler H. G. Fischer H. Frehse R. W. Frey S. Garpman W. Geist C. Gruhn P. Hanke M. Heiden W. Herr P. G. Innocenti T. J. Ketel E. E. Kluge I. Lund G. Mornacchi T. Nakada I. Otterlund M. Panter B. Povh A. Putzer E. Stenlund T. J. M. Symons R. Szwed O. Ullaland 《Zeitschrift fur Physik C Particles and Fields》1986,30(4):513-520
Properties of secondaries associated with a high-p T charged trigger particle (3<p T <5 GeV/c) were studied for αp and αα interactions at c.m. energies \(\sqrt s = 88\) GeV and 125 GeV, respectively. Thep T distributions of secondaries in the away-jet and trigger-jet regions were compared with those for high-p T pp interactions. No statistically significant differences were seen, except at lowp T . Momentum and angular distributions of spectator and leading protons were studied as a function of charge and rapidity of the trigger hadron. The observed correlations between trigger charge and number of spectator protons provide evidence of valence quark contributions to the trigger jet. 相似文献
8.
Zusammenfassung Für Elementbestimmungen in Abwasser wird ein Röntgenfluorescenzverfahren beschrieben. Zur Probenvorbereitung werden die Elemente durch Gefriertrocknung auf einem inerten Träger angereichert. Diese Anreicherung ist nicht selektiv und erfaßt praktisch alle in Abwasser gelösten und suspendierten Verunreinigungen. Für die Berechnung der Elementkonzentrationen aus den gemessenen Fluorescenzintensitäten wird ein Matrixkorrekturverfahren angegeben, welches dem unterschiedlichen Absorptionsverhalten der Probenmatrix Rechnung trägt. Die Massenabsorptionskoeffizienten werden durch Messung der diffus gestreuten Bremsstrahlung bzw. der Comptonstreustrahlung ermittelt. Die Selbstabsorption des zu bestimmenden Elementes wird rechnerisch berücksichtigt. Das Korrekturverfahren kann auf alle mit Röntgenfluorescenzanalyse bestimmbaren Elemente angewendet werden.
Determination of elements in waste water by x-ray fluorescence analysis: Sample preparation and matrix correction method
Summary For sample preparation the elements are enriched upon an inert carrier by freeze-drying. This enriching procedure is not selective and collects all dissolved and suspended contaminations from the waste water. In order to calculate the element concentrations from the measured fluorescence intensities a matrix correction method is given which considers the different absorption behaviour of the matrix. The mass absorption coefficients are obtained by measuring the scattered X-ray tube spectrum or a Compton scattered X-ray tube line, respectively. The self-absorption of the element to be determined is taken into account. The correction method is applicable to all elements detectable by X-ray fluorescence.
Herrn Dr. H. Wagner danken wir für das stete Interesse, die zahlreichen konstruktiven Diskussionen und die Hilfe beim Abfassen des Manuskripts. 相似文献
9.
Emilie Barriau Holger Frey Anton Kiry Manfred Stamm Franziska Gröhn 《Colloid and polymer science》2006,284(11):1293-1301
The preparation of carboxylated hyperbranched polyglycerols of narrow polydispersity was achieved by modification (78–90%) of the hydroxyl end groups via Michael addition of acrylonitrile, followed by hydrolysis. High conversion could only be achieved for low molecular weight starting materials (520 and 1,030 g mol−1). The solution properties of the resulting materials were investigated by dynamic light scattering (DLS), showing the formation of large aggregates with size depending on the pH value. After deposition on a negatively charged mica surface, the structures observed by atomic force microscope (AFM) show the coexistence of aggregates and single macromolecules. Most interesting, in the case of the lower molecular weight sample (PG 520 g mol−1), extended and ordered terrace structures were formed, which are unprecedented for hyperbranched polymers and are of interest for surface modification in general. 相似文献
10.
Zbigniew Grobelny Adalbert Maercker Janusz Kasperczyk Holger Frey 《Journal of organometallic chemistry》2004,689(14):2361-2367
The course of the reaction of alkalide K−, K+(15-crown-5)21 with selected alcohols depends on the kind of alcohol and the mode of substrate delivery. In the case of methanol, potassium methoxide formed initially undergoes destruction at the excess of 1. It results in potassium oxide and methylpotassium. The latter opens the crown ether ring giving potassium tetraethylene glycoxide vinyl ether and methane. A similar course of the process is observed for propanol. Potassium glycidoxide is the main product formed in the reaction of 1 with glycidol. Its oxirane ring is opened at the excess of 1. Organopotassium alkoxides, i.e., potassium potassiomethoxide and dipotassium potassiopropane-1,2-dioxide are intermediate products of this reaction. They react then with the crown ether. Potassium methoxide, potassium enolate of acetaldehyde, dipotassium propane-1,2-dioxide and potassium tetraethylene glycoxide vinyl ether are the final products of this process. 相似文献