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81.
The generation of slugs was studied for air–water flow in horizontal 0.0763 m and 0.095 m pipes. The emphasis was on high liquid rates (uLS ? 0.5 m/s) for which slugs are formed close to the entry and the time intervals between slugs are stochastic. A “fully developed” slug flow is defined as consisting of slugs with different sizes interspersed in a stratified flow with a height slightly larger than the height, h0, needed for a slug to be stable. Properties of this “fully developed” pattern are discussed. A correlation for the frequency of slugging is suggested, which describes our data as well as the data from other laboratories for a wide range of conditions. The possibility is explored that there is a further increase of slug length beyond the “fully developed” condition because slugs slowly overtake one another. 相似文献
82.
Vinay Girijavallabhan Ashok Arasappan Frank Bennett Yuhua Huang F. George Njoroge Malcolm MacCoss 《Tetrahedron letters》2010,51(21):2797-6881
Novel substituted thiazole[4,5-c]pyridines have been synthesized in good yields from unsubstituted thiazole[4,5-c]pyridine using direct C-H coupling reactions and N-oxide rearrangement chemistry. 相似文献
83.
Michael A. Beckett Elliot L. Bennett Michael B. Hursthouse 《Journal of organometallic chemistry》2010,695(7):1080-1083
The salts, [Ph2B{OCH2CH2N(Me)(CH2)n}2][Ph4B3O3] (n = 4, 5), were prepared in moderate yields in MeOH solution from reaction of Ph2BOBPh2 with [N(CH2)n(Me)(CH2CH2OH)][OH] and PhB(OH)2 in a 1:2:4 ratio. The reactions also lead to Ph3B3O3. Both salts were characterized by NMR (1H, 13C, 11B) IR, and single-crystal XRD studies. The salts are comprised of cationic monoborates (zwitterionic, 2N+ and 1B−) and tetraphenylboroxinate anions. 相似文献
84.
Adare A Afanasiev S Aidala C Ajitanand NN Akiba Y Al-Bataineh H Alexander J Angerami A Aoki K Apadula N Aphecetche L Aramaki Y Asai J Atomssa ET Averbeck R Awes TC Azmoun B Babintsev V Bai M Baksay G Baksay L Baldisseri A Barish KN Barnes PD Bassalleck B Basye AT Bathe S Batsouli S Baublis V Baumann C Bazilevsky A Belikov S Belmont R Bennett R Berdnikov A Berdnikov Y Bhom JH Bickley AA Blau DS Boissevain JG Bok JS Borel H Boyle K Brooks ML Buesching H Bumazhnov V Bunce G Butsyk S Camacho CM 《Physical review letters》2011,107(14):142301
We present measurements of J/ψ yields in d+Au collisions at sqrt[s(NN)]=200 GeV recorded by the PHENIX experiment and compare them with yields in p+p collisions at the same energy per nucleon-nucleon collision. The measurements cover a large kinematic range in J/ψ rapidity (-2.2相似文献
85.
Bennett RG Zhelev N Smith EN Pollanen J Halperin WP Parpia JM 《Physical review letters》2011,107(23):235504
Motivated by the recent prediction that uniaxially compressed aerogel can stabilize the anisotropic A phase over the isotropic B phase, we measure the pressure dependent superfluid fraction of (3)He entrained in 10% axially compressed, 98% porous aerogel. We observe that a broad region of the temperature-pressure phase diagram is occupied by the metastable A phase. The reappearance of the A phase on warming from the B phase, before superfluidity is extinguished at T(c), is in contrast to its absence in uncompressed aerogel. The phase diagram is modified from that of pure (3)He, with the disappearance of the polycritical point (PCP) and the appearance of a region of A phase extending below the PCP of bulk (3)He, even in zero applied magnetic field. The expected alignment of the A phase texture by compression is not observed. 相似文献
86.
W. H. Bennett W. I. H. Moll H. C. Burger H. F. Mullikin J. A. Campbell J. H. Hibben A. Beck W. K. Hutchison K. A. Kobe S. Pexton E. J. Arveson Fr. Strieck Ch. W. Wilson W. Ackermann O. Pfundt Y. Kauko W. Mc K. Martin J. R. Green M. Kleiber H. Briese E. Biesalski H. Giehmann M. Mugdan J. Sixt R. Ruyssen N. Allen G. Denigès F. W. Horst L. Benoist H. Tramm W. Grimme P. Schuftan H. Tropsch R. Kassler W. Deckert M. Konschak C. Aßmann L. E. Karlsson H. L. Cupples W. Klempt W. Riese J. H. Bruun M. M. Hicks-Bruun E. C. Mathis 《Analytical and bioanalytical chemistry》1934,96(9-10):336-346
87.
Francisco J. Jiménez‐Hornero Juan V. Giráldez Ana M. Laguna Sean J. Bennett Carlos V. Alonso 《国际流体数值方法杂志》2007,55(7):655-672
A two‐dimensional lattice model has been developed to describe the influence of vegetation on the turbulent flow structure in an open channel. The model includes the influence of vegetation density on the frictional effect of the channel bed and walls. For the walls, a semi‐slip boundary condition has been considered as an alternative to overcome the no‐slip boundary condition limitations in turbulent flows. The drag stress exerted by the flow on the vegetation as well as the gravity effect has also been taken into account. The proposed lattice model has been used to simulate the experimental results reported from the study of the influence of alternate vegetated zones on the open‐channel flow. The results show that the lattice model approach is a valid tool for describing these kinds of flows. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
88.
Maps and Globes Jack Knowlton Hurricane Watch Franklyn M. Branley Sunshine Makes the Seasons Franklyn M. Branley Heart Disease America's No. 1 Killer Dr. Alvin and Virginia B. Silverstein Cuts, Breaks, Bruises and Burns Joanna Cole Auks, Rocks, and the Odd Dinosaur Inside Stories from the Smithsonian Institute by Peggy Thomson The Secret Life of Cosmetics: A Science Experiment Book Vicki Cobb A Children's Zoo Tana Hoban Milk Donald Carrick Wallaby Creek Joyce Powzyk Being a Twin, Having a Twin Maxine Rosenberg 相似文献
89.
N.D McCavishR.A Bennett 《Surface science》2003,546(1):47-56
We have employed low energy electron diffraction (LEED) and X-ray photoelectron spectroscopy to follow the epitaxial growth of thin films of TiO2 on W(1 0 0). The films were grown both by metal vapour deposition of titanium onto the substrate in UHV with subsequent annealing in a low partial pressure of oxygen, and by metal vapour deposition in a low partial pressure of oxygen. LEED patterns showed the characteristic patterns of (1 1 0) oriented rutile. A systematic spot splitting was observed and attributed to a stepped surface. The calculated step height was found to be in good agreement with that expected for rutile TiO2(1 1 0), 3.3 Å. Titanium core level shifts were used to identify oxidation states as a function of film thickness allowing the interpretation in terms of a slightly sub-stoichiometric interface layer in contact with the substrate. In combination with the LEED patterns, the film structure is therefore determined to be (1 1 0) oriented rutile with a comparable level of stoichiometry to UHV prepared bulk crystals. The ordered step structure indicates considerable structural complexity of the surface. 相似文献
90.