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961.
962.
963.
Abraham J Abreu P Aglietta M Aguirre C Allard D Allekotte I Allen J Allison P Alvarez-Muñiz J Ambrosio M Anchordoqui L Andringa S Anzalone A Aramo C Argirò S Arisaka K Armengaud E Arneodo F Arqueros F Asch T Asorey H Assis P Atulugama BS Aublin J Ave M Avila G Bäcker T Badagnani D Barbosa AF Barnhill D Barroso SL Bauleo P Beatty JJ Beau T Becker BR Becker KH Bellido JA BenZvi S Berat C Bergmann T Bernardini P Bertou X Biermann PL Billoir P Blanch-Bigas O Blanco F Blasi P Bleve C Blümer H 《Physical review letters》2008,100(21):211101
The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau neutrinos that interact in Earth's crust. Tau leptons from nu(tau) charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and 31 August 2007 are used to place an upper limit on the diffuse flux of nu(tau) at EeV energies. Assuming an E(nu)(-2) differential energy spectrum the limit set at 90% C.L. is E(nu)(2)dN(nu)(tau)/dE(nu)<1.3 x 10(-7) GeV cm(-2) s(-1) sr(-1) in the energy range 2 x 10(17) eV< E(nu)< 2 x 10(19) eV. 相似文献
964.
Abraham Mehrez Zilla Sinuany-Stern Tal Arad-Geva Shemuel Binyamin 《The Journal of the Operational Research Society》1996,47(5):612-625
Recently a public committee has been appointed by the Israeli government. The committee was assigned to prepare regional plans for the northeastern Negev, in the southern part of Israel, in order to absorb some of the large waves of immigrants (about 400,000) expected by the year 2000. Among the strategic issues treated by the committee were the questions when, where and whether to build a new hospital in the area. The locational decision was studied by first identifying a finite candidate set of possible sites. At the final stage various quantitative locational models were employed. In the next stage a subjective multicriteria model was further used to derive locationally preferred solutions. This paper focuses on the first stage. Furthermore, the suggested solution approach is discussed in light of strategic issues. 相似文献
965.
Acoustic non-linearity parameter B/A is calculated for five binary liquid mixtures using Tong and Dong equation along with
the Flory’s statistical theory. Similar to other excess thermodynamical quantities an excess non-linearity parameter (B/A)E is defined for binary liquid mixtures. The interactions in the liquid mixtures are explained on the basis of the excess non-linearity
parameter. 相似文献
966.
We discuss the thermal instability in a layer of dielectric fluid when the boundaries of the layer are subjected to small amplitude Time-periodic body force (TBF). Perturbation solution in powers of the amplitude of the applied temperature field is obtained using the Venezian method (1969) [1]. A linear stability analysis is performed. The results of the study, indicate that TBF or g-jitter leads to delayed convection Also for large frequencies the effect of TBF disappears.The problem has relevance in many dielectric fluid applications wherein regulation of thermal convection is called for. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
967.
Marielba Rojas Yonas B. Abraham Natalie A. W. Holzwarth Robert J. Plemmons 《PAMM》2007,7(1):2060001-2060002
We propose a new approach based on surrogate modeling for geometry optimization in material design. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
968.
Abraham Berman 《Linear algebra and its applications》2006,419(1):1-7
The purpose of this note is to address the computational question of determining whether or not a square nonnegative matrix (over the reals) is completely positive and finding its CP-rank when it is. We show that these questions can be resolved by finite algorithms and we provide (non-polynomial) complexity bounds on the number of arithmetic/Boolean operations that these algorithms require. We state several open questions including the existence of polynomial algorithms to resolve the above problems and availability of algorithms for addressing complete positivity over the rationals and over {0, 1} matrices. 相似文献
969.
Sinoj Abraham Chang‐Sik Ha Il Kim 《Journal of polymer science. Part A, Polymer chemistry》2006,44(9):2774-2783
The self‐assembling nature and phase‐transition behavior of a novel class of triarm, star‐shaped polymer–peptide block copolymers synthesized by the combination of atom transfer radical polymerization and living ring‐opening polymerization of α‐amino acid‐N‐carboxyanhydride are demonstrated. The two‐step synthesis strategy adopted here allows incorporating polypeptides into the usual synthetic polymers via an amido–amidate nickelacycle intermediate, which is used as the macroinitiator for the growth of poly(γ‐benzyl‐L ‐glutamate). The characterization data are reported from analyses using gel permeation chromatography and infrared, 1H NMR, and 13C NMR spectroscopy. This synthetic scheme grants a facile way to prepare a wide range of polymer–peptide architectures with perfect microstructure control, preventing the formation of homopolypeptide contaminants. Studies regarding the supramolecular organization and phase‐transition behavior of this class of polymer‐block‐polypeptide copolymers have been accomplished with X‐ray diffraction, infrared spectroscopy, and thermal analyses. The conformational change of the peptide segment in the block copolymer has been investigated with variable‐temperature infrared spectroscopy. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2774–2783, 2006 相似文献
970.
Nagaraja SreeHarsha Jagadeesh G. Hiremath Rajesh Kumar Aitha Abraham J. Domb Bandar E. Al‐Dhubiab Chandramouli Ramnarayanan Abdullah Mossa Alzahrani Katharigatta N. Venugopala Sabah H. Akrawi Mahesh Attimarad Anroop B. Nair 《先进技术聚合物》2019,30(10):2613-2622
This research presents a thin‐film hydration‐solvent evaporation method to formulate the paclitaxel loaded poly (DL lactic acid co castor oil) 4:6 with poloxamer‐F68 cylindrical shape nanoparticles. The particles were less than 250 nanometers (nm) in size, with an average width of 60 nm and an average length of 100 nm. The percent yield, encapsulation efficiency (EE), and percent drug loading (DL) were detected. This approach produces drug loading values between 5% and 20% w/w. X‐ray powder diffraction (XRD) identified the physicochemical properties of nanoparticles differential scanning calorimetry (DSC) and Fourier‐transform infrared spectroscopy (FTIR). The investigation shows that the drug is molecularly dispersed in polymers or given in an amorphous or semicrystalline state. Horizontal water bath shaker technology considered the in vitro release of PTX loaded nanoparticles under sink conditions. Poly (DL lactic acid co castor oil) 4:6 nanoparticles exhibited a sustained release analysis. At the end of 30 hours, the percent cumulative drug release from the formulations was between 74.52% and 92.87% for F1 and F4. In vitro cytotoxicity assays indicate that PTX having p (DLLA:CO60:40) nanoparticles have a higher cytotoxic effect on MCF‐7/ADR. 相似文献