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41.
L. Baum M. Block A. Böhm F. Ceradini D. DiBitonto J. Irion A. Kernan J. Layter F. Muller A. Nakkasyan B. Naroska F. Navach M. Nussbaum A. Orkin-Lecourtois C. Rubbia D. Schinzel H. Seebrunner B. Shen R. Wojslaw 《Physics letters. [Part B]》1978,77(3):337-338
From a search for e±μ± production at the CERN ISR an upper limit of 0.92 μb (95% confidence limit) has been inferred for σ·Be·Bμ for the reaction . 相似文献
42.
43.
Bryan A. Baum Ping Yang Yong-Xiang Hu Qian Feng 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(17-18):2534-2549
The goal of this study is to explore the influence of ice particle habit (or shape) and surface roughness on the scattering phase matrix. As an example, reported here are the results for two wavelengths: 0.67 and 1.61 μm. For this effort, a database of single-scattering properties has been computed for a set of habits including hexagonal plates, hollow and solid columns, hollow and solid 3D bullet rosettes, droxtals, aggregates of solid columns, and aggregates of plates. The database provides properties for each of the habits at 101 wavelengths between 0.45 and 2.24 μm for smooth, moderately roughened, and severely roughened particles. At each wavelength, the scattering properties are provided at 233 discrete particle diameters ranging from 2 to 10,000 μm. A single particle size distribution from a very cold ice cloud sampled during the CRYSTAL-FACE field campaign (Tcld=–76 °C) is used to illustrate the influence of habit and roughness on the phase matrix. In all, four different habit mixtures are evaluated. The nonzero elements of the phase matrix are shown to be quite sensitive to the assumed habit, particularly in the case of ?P12/P11 that is associated with the degree of linear polarization of scattered radiation. Surface roughness is shown to smooth out maxima in the scattering phase function and in the other elements of the phase matrix, consistent with other studies. To compare with the theoretical simulations of the phase matrix for smooth and roughened particles, a full year of cloud-aerosol lidar with orthogonal polarization (CALIOP) data from 2008 is analyzed to provide global statistics on the values of P11 and P22/P11 in the backscattering direction. In a comparison of two of the habit mixtures (one used for MODIS Collection 5 and another that incorporates new habits including hollow bullet rosettes and aggregates of plates) with the CALIOP data, the values for P11 are higher regardless of the degree of particle surface roughness, and the values for P22/P11 are lower than those for CALIOP. Further investigation is warranted to better understand this discrepancy. 相似文献
44.
D. Baum 《Journal of Mathematical Sciences》1998,92(4):3990-4002
Stochastic models of high-speed communication systems typically require the analysis of special Markov additive processes,
known thus far as “batch Markovian arrival processes” (BMAPs). In most cases, the solution of nonlinear matrix equations of
the form
or
is necessary, leading, in general, to severe numerical problems. Several efficient algorithms for that purpose have been
reported in the literature. In this contribution, we present a new approach (the BMAP|G| 1-analysis), which is based on a
convolution calculus for matrix sequences. The main results are the unified representation of Poisson, compound Poisson, and
batch Markovian arrival processes by so-called convolutional exponential distributions, and the computation of the fundamental-period
matrix G via so-called semi-convolutions. The resulting algorithms, in general, cannot outperform known algorithms as, for
instance, those exploiting Horner schemes as proposed by D. M. Lucantoni and other authors, or the highly efficient cyclic
reduction algorithm of D. Bini and B. Meini; nevertheless, they allow the direct computation of step matrices such as the
“arrival matrices” An with
and the component matrices Gn summing to G. Further, there is some hope that the proposed framework may lead to a unification of the theory in the sense
that queues with arrival and/or service processes that are characterized by convolutional exponential distributions may possess
formally similar properties, as known from the scalar case.
Proceedings of the Seminar on Stability Problems for Stochastic Models. Hajdúszoboszló. Hungary, 1997. Part II. 相似文献
45.
Kornauth Wilh Bersch A. Philips Christ. Kob und Co. Donner Louise H. Weller C. Schweitzer Ch. L. Penny Ed. van Melckebeke H. J. Wheeler B. Hartwell Knorr W. Büttner Barthé W. Jerwitz C. F. Parker Gust Christ Ferdinand Kryz J. Katz H. Göckel R. Jabota J. J. L. von Rijn F. Baum Joseph Nerking A. E. Taylor J. Gadamer C. Th. L. Hagemann und C. A. Neufeld 《Fresenius' Journal of Analytical Chemistry》1902,41(11):686-695
Ohne Zusammenfassung 相似文献
46.
Kornauth Wilh Bersch A. Philips Donner Dr. Louise H. Weller C. Schweitzer Ch. L. Penny Ed. van Melckebeke H. J. Wheeler B. Hartwell Knorr W. Büttner Barthé W. Jerwitz C. F. Parker Gust Christ Ferdinand Kryz J. Katz H. Göckel R. Jabota J. J. L. von Rijn F. Baum Joseph Nerking A. E. Taylor J. Gadamer C. Th. L. Hagemann C. A. Neufeld Christ. Kob und Co. 《Analytical and bioanalytical chemistry》1902,41(11):686-695
47.
Gottschaldt M Koth D Müller D Klette I Rau S Görls H Schäfer B Baum RP Yano S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(36):10273-10280
Novel ligands have been obtained from the reaction of 4,4'-dibromomethyl-2,2'-bipyridine with 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosylthiol, 2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosylthiol or 2,3,4,6-tetra-O-acetyl-alpha-D-thioacetylmannopyranoside in which the sugar residues are thioglycosidically linked to the bipyridine in the 4,4'-position. Cleavage of the acetyl groups affords hydrophilic symmetric ligands with free hydroxyl groups. Reaction of the new glycoconjugated ligands (L) with [Re(CO)(5)Cl] yields fluorescent complexes of general formula [Re(L)(CO)(3)Cl], which were characterised by mass spectrometry, elemental analysis and (1)H and (13)C NMR, IR, UV/Vis and fluorescence spectroscopy. These complexes exhibit excellent solubility and stability in organic solvents or water, depending on the residues of the sugar. One complex, namely tricarbonyl-4,4'-bis[(2,3,4,6-tetra-O-acetyl-beta-D-glycopyranosyl)thiomethyl]-2,2'-bipyridinerheniumtricarbonylo chloride, has been characterised by X-ray crystallography. A non-symmetric structure of the complexes could be assigned. Radiolabelling of the unprotected ligands with [(99m)Tc(H(2)O)(3)(CO)(3)](+) affords the corresponding water-soluble technetium complexes (in quantitative yields), which were characterised by their HPLC radiation traces. The formed complexes are stable for several hours in the presence of histidine but show partial ligand-exchange after one day. 相似文献
48.
Andersen D Storz T Liu P Wang X Li L Fan P Chen X Allgeier A Burgos A Tedrow J Baum J Chen Y Crockett R Huang L Syed R Larsen RD Martinelli M 《The Journal of organic chemistry》2007,72(25):9648-9655
Melanin-concentrating hormone (MCH) is implicated in the feeding behavior in mammals affording a potential target to control overeating in people. Compound 1 (AMG 076) has been identified as a potent MCHr1 antagonist for the treatment of obesity. A synthesis suitable for the large-scale preparation of this lead candidate was developed to support preclinical studies. A Robinson annulation of benzylpiperidone and resolution of the desired enone from a mixture of the diastereomers afforded key intermediate 6 after a stereoselective hydrogenation. Subsequent Fischer indole synthesis with hydrazine 5 then provided the advanced intermediate, indole 2. Two complementary reductive amination strategies employing either aldehyde 3 or lactol 4 led to the synthesis of title compound 1. 相似文献
49.
Synthesis and Structure of two Mixed Substituted Dialanes Al2X2{Si(SiMe3)3}2 · 2 THF (X = Cl, Br) The syntheses of tris(trimethylsilyl)silyl (hypersilyl) and halide substituted dialanes Al2X2{Si(SiMe3)3}2 · 2 THF (X = Cl, Br) are presented. The results of the X‐ray diffraction experiments are presented and discussed in comparison to the AlIII compounds AlBr2Si(SiMe3)3 · THF and AlBr3 · OPh2. 相似文献
50.
Alexander Donchev Andreas Schnepf Elke Baum Gregor Stßer Hansgeorg Schnckel 《无机化学与普通化学杂志》2002,628(1):157-161
[Ga6R8]2– (R = SiPh2Me): A Metalloid Cluster Compound with an Unexpected Ga6‐Frame The reaction of a metastable solution of GaBr with a solution of LiSiPh2Me in a toluene/THF mixture results in orange coloured crystals of [Ga6(SiPh2Me)8]2– · 2 [Li(THF)4]+ ( 1 ). The unexpected structure of the planar Ga6 frame (C2h) could also be realized with the help of DFT calculation. DFT calculations furthermore show that 1 is energetically favoured against an octahedral Ga6R62– species and R2. In contrast calculations for the similar Al and B species show that in these cases the octahedral entities are favoured. These results demonstrate that even for similar compounds of B, Al, and Ga Wade rules are too general and that they cannot predict the correct structure. Moreover the atomic arrangement within 1 shows that a structure is preferred which is also present in allotropic β‐Ga and that therefore clusters of this type should be called metalloid or more general elementoid. 相似文献