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151.
Francis Jordan Sam B. Nadler Jr. 《Proceedings of the American Mathematical Society》2001,129(4):1219-1228
It is shown that a continuum that is an space in the sense of Michael must be hereditarily decomposable. This improves known results, thereby providing more evidence that such continua must be dendrites.
152.
We review:
- 1. The compelling case for doing neutrino astronomy,
- 2. Why we anticipate that we need kilometer-scale observatories to do the science,
- 3. The recent successful commissioning of the Lake Baikal and South Pole neutrino detectors.
References
1. a. K. Greisen Ann. Rev. Nucl. Science 10 (1960), p. 63.b. see also F. Reines Ann. Rev. Nucl. Science 10 (1960), p. 1.c. M.A. Markov and I.M. Zheleznykh Nucl. Phys. 27 (1961), p. 385. Abstract | PDF (896 K)
| View Record in Scopus | Cited By in Scopus (23)d. M.A. Markov In: E.C.G. Sudarshan, J.H. Tinlot and A.C. Melissinos, Editors, Proceedings of the 1960 Annual International Conference on High Energy Physics at Rochester (1960).
2. a. F. Halzen , The Case for a Kilometer-Scale Neutrino Detector. In: R. Kolb and R. Peccei, Editors, Nuclear and Particle Astrophysics and Cosmology, Proceedings of Snowmass 94 (1996).b. F. Halzen , The Case for a Kilometer-Scale Neutrino Detector: 1996. In: M. Baldo-Ceolin, Editor, Proc. of the Sixth International Symposium on Neutrino Telescopes (1996) Venice .
3. a. For a review, see T.K. Gaisser, F. Halzen and T. Stanev Phys. Rep. 258 3 (1995), p. 173. Abstract | Article | PDF (5524 K)
| View Record in Scopus | Cited By in Scopus (291)b. J.G. Learned and K. Mannheim Ann. Rev. Nucl. Part. Science 50 (2000), p. 679. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (179)c. R. Ghandi, E. Waxmann and T. Weiler review talks at Neutrino 2000, Sudbury, Canada (2000).
4. Jaime Alvarez, private communication.
5. DUMAND Collaboration J. Babson et al., Cosmic Rays in the Deep Ocean ICR-205-89-22, Dec. 1989, 24 pp., published in . Phys. Rev. D 42 (1990), p. 3613. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (33)
6. a. I.A. Belolaptikov et al.Astroparticle Physics 7 (1997), p. 263. Abstract | Article | PDF (1911 K)
| View Record in Scopus | Cited By in Scopus (20)b. V.A. Balkanov et al.Nucl. Phys. Proc. Suppl. 75A (1999), p. 409. Abstract | PDF (254 K)
| View Record in Scopus | Cited By in Scopus (7)
7. E. Aslanides et al.astro-ph/9907432 (1999).
8. L. Trascatti , Procs. of the 5th International Workshop on “Topics in Astroparticle and Underground Physics (TAUP 97) Gran Sasso, Italy, 1997 . In: A. Bottino, A. di Credico and P. Monacelli, Editors, Nucl. Phys. B70 (1998), p. 442 (Proc. Suppl.) .
9. Talk given at International Workshop on Next Generation Nucleon Decay and Neutrino Detector (NNN99) (1999) Stony Brook, Proceedings to by published by AIP. .
10. The AMANDA collaboration, The AMANDA Neutrino Telescope: Principle of Operation and First Results. Astroparticle Physics 13 (2000), p. 1.
11. AMANDA collaboration A. Karle , Observation of Atmospheric Neutrinos with the AMANDA Experiment, to be published. Proceedings of the 17th International Workshop on Weak Interactions and Neutrinos (1999) Cape Town, South Africa .
12. a. E. Andres et al., Nature, submitted for publication.b. see also S. Barwick Proceedings of Neutrino 2000, Sudbury, Canada (2000).
13. a. F. Stecker, C. Done, M. Salamon and P. Sommers Phys. Rev. Lett. 66 (1991), p. 2697. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (143)b. erratum F. Stecker, C. Done, M. Salamon and P. Sommers Phys. Rev. Lett. 69 (1992), p. 2738. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (69)
相似文献
153.
Gaussian polynomials are used to define bases with good multiplicative properties for the algebra K
*(K) of cooperations in K-theory and for the invariants under conjugation. 相似文献
154.
Equivalence of sketches S and T means the equivalence of their categories ModS and ModT of all Set-valued models. E. Vitale and the second author have characterized equivalence of limit-sketches by means of bimodels, where a bimodel for limit sketches S and T is a model of S in the category ModT. For general sketches, we show that an analogous result holds provided that ModT is substituted by a more complex category; e.g., in case of limit-coproduct sketches, that category is (ModT), the free product completion of ModT. 相似文献
155.
Paul Francis Bracken 《International Journal of Theoretical Physics》2007,46(1):116-129
The problem of studying the quantum Hall effect on manifolds with non constant metric is addressed. The Hamiltonian on a space
with hyperbolic metric is determined, and the spectrum and eigenfunctions are calculated in closed form. The hyperbolic disk
is also considered and some other applications of this approach are discussed as well.
PACS numbers: 73.43.-f, 02.30.Jr. 相似文献
156.
Ekaterina A. Martynova Vladislav A. Voloshkin Sbastien G. Guillet Francis Bru Marek Beli Kristof Van Hecke Catherine S. J. Cazin Steven P. Nolan 《Chemical science》2022,13(23):6852
We present the use of gold sensitizers [Au(SIPr)(Cbz)] (PhotAu 1) and [Au(IPr)(Cbz)] (PhotAu 2) as attractive alternatives to state-of-the-art iridium-based systems. These novel photocatalysts are deployed in [2 + 2] cycloadditions of diallyl ethers and N-tosylamides. The reactions proceed in short reaction times and in environmentally friendly solvents. [Au(SIPr)Cbz] and [Au(IPr)(Cbz)] have higher triplet energy (ET) values (66.6 and 66.3 kcal mol−1, respectively) compared to commonly used iridium photosensitizers. These ET values permit the use of these gold complexes as sensitizers enabling energy transfer catalysis involving unprotected indole derivatives, a substrate class previously inaccessible with state-of-the-art Ir photocatalysts. The photosynthesis of unprotected tetracyclic spiroindolines via intramolecular [2 + 2] cycloaddition using our simple mononuclear gold sensitizer is readily achieved. Mechanistic studies support the involvement of triplet–triplet energy transfer (TTEnT) for both [2 + 2] photocycloadditions.We present the use of gold sensitizers [Au(SIPr)(Cbz)] (PhotAu 1) and [Au(IPr)(Cbz)] (PhotAu 2) as attractive alternatives to state-of-the-art iridium-based systems. 相似文献
157.
158.
Murielle Rivenet Nicolas Vigier Pascal Roussel Francis Abraham 《Journal of solid state chemistry》2007,180(2):713-724
Six new layered uranyl vanadates (NH4)2[(UO2)2V2O8] (1), (H2EN)[(UO2)2V2O8] (2), (H2DAP)[(UO2)2V2O8] (3), (H2PIP)[(UO2)2(VO4)2].0,8H2O (4), (H2DMPIP)[(UO2)2V2O8] (5), (H2DABCO)[(UO2)2(VO4)2] (6) were prepared from mild-hydrothermal reactions using 1,2-ethylenediamine (EN); 1,3-diaminopropane (DAP); piperazine (PIP); 1-methylpiperazine (MPIP); 1,4-diazabicyclo[2,2,2]octane (DABCO). The structures of 1, 4, 5 and 6 were solved using single-crystal X-ray diffraction data while the structural models of 2 and 3 were established from powder X-ray diffraction data. In compounds 1, 2, 3 and 5, the uranyl-vanadate layers are built from dimers of edge-shared UO7 pentagonal bipyramids and dimers of edge-shared VO5 square pyramids further connected through edge-sharing. In 1 and 3, the layers are identical to that occurring in the carnotite group of uranyl-vanadates. In 2 and 5, the V2O8 dimers differ in orientation leading to a new type of layer. The layers of compound 4 and 6 are built from chains of edge-shared UO7 pentagonal bipyramids connected by VO4 tetrahedra and are of uranophane-type anion topology. For the six compounds, the ammonium or organoammonium cation resides in the space between the inorganic layers. Crystallographic data: 1 monoclinic, space group P21/c with a=6.894(2), b=8.384(3), c=10.473(4) Å and β=106.066(5)°, 2 monoclinic, space group P21/a with a=13.9816(6), b=8.6165(3), c=10.4237(3) Å and γ=93.125(3)°, 3 orthorhombic, space group Pmcn with a=14.7363(8), b=8.6379(4) and c=10.4385(4) Å, 4 monoclinic, space group C2/m with a=15.619(2), b=7.1802(8), c=6.9157(8) Å and β=101.500(2)°, 5 monoclinic, space group P21/b with a=9.315(2), b=8.617(2), c=10.5246(2) Å and γ=114.776(2)°, 6 monoclinic, space group C2/m with a=17.440(2), b=7.1904(9), c=6.8990(8) Å and β=98.196(2)°. 相似文献
159.
Mieszawska AJ Jalilian R Sumanasekera GU Zamborini FP 《Journal of the American Chemical Society》2005,127(31):10822-10823
This contribution describes the synthesis of gold nanorod (Au NR)/single-wall carbon nanotube (SWCNT) heterojunctions assembled directly on Si/SiOx substrates. SWCNTs are attached to amine-functionalized Si/SiOx substrates, and Au monolayer-protected clusters (MPCs) are adsorbed to the surface of SWCNTs through hydrophobic interactions. Seed-mediated reduction of HAuCl4 with ascorbic acid in the presence of cetyltrimethylammonium bromide (CTAB) onto the Au MPCs leads to the growth of larger Au nanostructures directly on the SWCNTs. Au NRs account for 19% of the nanostructures, some of which are attached directly to the sidewall and some at the ends of the SWCNTs. Raman spectroscopic measurements of SWCNTs before and after growth of the Au nanostructures reveal that the presence of Au leads to an approximately 50-fold enhancement of the Raman scattering signal. Combining 1D nanostructures of different materials (Au and carbon in this example) is of fundamental interest and may find use in nanoelectronics, chemical sensing, electrochemical, and spectroscopy applications. 相似文献
160.
利用“一步法”合成并表征了4种碱性金属修饰的金属有机骨架材料MOF-5(记作M-MOF-5,M=Li,Na,K,Mg)。 并应用理想溶液吸附理论(IAST)对样品吸附选择性进行计算比较。 结果表明,碱性金属掺入可以降低MOF-5材料骨架结构的“互穿”程度,同时,在常温常压下,M-MOF-5对CO2/CH4的吸附选择性相对MOF-5(选择性为3.79)有着显著提高,尤其是Li-MOF-5(选择性为7.39)。 此外,Li-MOF-5的CO2捕获能力相对MOF-5也有提高。 相似文献