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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Search for supersymmetry using rare B to mumu decays at CDF run II

Krutelyov, Vyacheslav 12 April 2006 (has links)
A search for rare B0 s -> µ+µ- and B0d -> µ+µ- decays has been performed in pp collisions at sqroot(s) = 1.96 TeV using 364 pb-1 of data collected by the CDF II experiment at the Fermilab Tevatron Collider. The rate of each decay is sensitive to contributions from physics beyond the Standard Model (SM). No events pass the optimized selection requirements, consistent with the SM expectation. The resulting upper limits on the branching ratios are B(B0s -> µ+µ-) < 1.5 x 10-7 and B(B0d -> µ+µ-) < 3.8 x 10-8 at the 90% confidence level. The limits are used to exclude some parameter space for several supersymmetric models.
42

Spin-correlation effects in lanthanide ion spectra /

Siu, Guei-gu. January 1983 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1984.
43

Noble gases and catalysis

Cunje, Alwin. January 2000 (has links)
Thesis (Ph. D.)--York University, 2000. Graduate Programme in Chemistry. / Typescript. Includes bibliographical references. Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pNQ59125.
44

Exploring new ligand environments for lanthanide coordination chemistry

Moore, Jennifer Anne 28 August 2008 (has links)
Not available / text
45

Solubility and partitioning of noble gases in anorthite, diopside, forsterite, spinel, and synthetic basaltic melts: Implications for the origin and evolution of terrestrial planet atmospheres.

Broadhurst, Catherine Leigh. January 1989 (has links)
The noble gas abundances and isotopic ratios of the terrestrial planets differ from each other and from the average of chondritic meteorites. These different abundance patterns result from primordial heterogeneities or different degassing histories. Magmatic transport is the only degassing mechanism that can be demonstrated to occur on Venus, Earth, and Mars, and is presently the dominant form of volatile transport to a planet's free surface. An alternative technique was developed to determine the partitioning and solubility of noble gases in mineral/melt systems. Natural end member minerals and synthetic melts known to be in equilibrium were held in separate crucibles in a one bar flowing noble gas atmosphere. Experiments were run 7-18 days at 1300 or 1332°C, in 99.95% Ar or a Ne-Ar-Kr-Xe mix. Gas concentrations were measured by mass spectrometry. The solubility of noble gases in minerals was surprisingly high, and individual samples of a particular mineral composition are distinct in their behavior. The data is consistent with lattice vacancy defect siting. Noble gas solubility in the minerals increases with increasing atomic number; this may be related to polarizability. Noble gas solubilities in melts decrease with increasing atomic number. Solubility is directly proportional to melt molar volume; values overlap the lower end of the range defined for natural basalts. The lower solubilities are related to the higher MgO and CaO concentrations and lower degree of polymerization and Fe³⁺ concentration in synthetic vs. natural melts. Partition coefficient patterns show a clear trend of increasing compatibility with increasing noble gas atomic number, but many individual values are > 1. Calculations show that the terrestrial planet atmospheres cannot have formed from partial melting of a common chondritic source. When results are examined with isotopic constraints and MOR and hot-spot activities, there is no compelling evidence that the Earth is substantially outgassed of its primordial or even its radiogenic volatiles. If volcanic degassing was mostly responsible for the atmospheres, then initial volatile abundances were Mars < Earth < Venus. Alternatively, roughly equal abundances could have been modified by catastrophic processes.
46

ELECTROANALYTICAL CHEMISTRY OF THE RARE-EARTHS

Cokal, Edward Joseph, 1935- January 1963 (has links)
No description available.
47

Formation of ester adducts of lanthanide shift reagents

Merali, Arzina Muradali. January 1975 (has links)
No description available.
48

The measurement of the rare kaon decay k-plus to pi-plus, neutrino and anti-neutrino

Ives, Joss 05 1900 (has links)
Brookhaven National Laboratory experiment E949 was designed to search for the rare K meson decay K⁺ → π⁺ , neutrino, and anti-neutrino, a decay sensitive to physics beyond the Standard Model. While previous data analyses dealt with the high π⁺ momentum region accessible for this reaction, this thesis concentrates on the lower range between 140 and 199 MeV/c. Analysis of this low π⁺ momentum region was performed to search for additional evidence of the process K⁺ → π⁺, neutrino, and anti-neutrino. A blind analysis technique was used to avoid bias when developing the selection criteria used to suppress the competing background processes. The blind analysis technique was based on identifying background sources a priori and only examining the signal region once all selection criteria and background estimates had been finalized. The background estimates were performed using a technique known as a "bifurcation method", which relied on using two uncorrelated selection criteria to suppress each background source. The analysis of an exposure of 1.71 x 10¹² K⁺ decays resulted in an observation of three events with an estimated background of 0.927 ± 0.168(stat.)⁺³²⁰-₀.₂₃₇(sys.) events and a single event sensitivity of (4.28 ± 0.43)x 10-¹⁰. Using a likelihood method, the three candidate events observed here were combine with the previous E787 and E949 results, yielding a branching ratio of ϐ(K⁺ → π⁺, neutrino, and anti-neutrino decay of (1.73+1.15-1.05) x 10⁻¹⁰ at the 68% confidence level. This branching ratio is consistent with the prediction of the Standard Model, (0.85 ± 0.07) x 10⁻¹⁰.
49

Development of a calorimeter for studying gas phase reactions, and measurements of the heat of formation of xenon hexafluoride and phosphorus trifluoride

Selph, Curtis Carroll 12 1900 (has links)
No description available.
50

Effect of temperature on the crystal structure of lanthanum, cerium, neodymium, and paraseodymium The relation between crystal structure and superconductivity

Floyd, Acey LeeRoy 08 1900 (has links)
No description available.

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