Search results for "ZEN"

ChemInform Abstract: New Reactions of 2- and 3-Vinylindoles with Azodienophiles, Diethyl Mesoxalat, and Nitrosobenzene: An Access to Functionalized a…

2010

ChemInform Abstract: First Transformations of Pyrano(3,4-b)indol-3-ones to Salvadoricine and 2,3-Diacylindoles.

2010

The readily available methylated pyrano[3,4-b]indol-3-ones 1a and 1b were hydrolyzed to furnish the 2-acetylindol-3-alkanoic acids 2 and 4. Compound 2 was easily transformed selectively to 2-acetyl-3-methylindole (3, salvadoricine). Substrate 1b reacts with molecular oxygen from the air only in the presence of a catalyst to give 2,3-diacetylindole (5) while 1a reacts with nitrosobenzene via a proposed Diels-Alder step to yield 2-acetylindole-3-carbaldehyde (6). The latter product can also be obtained in low yield from the reaction of 1a with molecular oxygen from the air.

2,2-Diphenylbenzo[c]quinoline-1-oxyl

2009

In the title compound, C25H18NO, a stable phenanthridinic nitroxide, the ring containing the nitroxide function assumes a twist-boat conformation and the dihedral angle formed by adjacent benzene rings is 21.78 (5)°. The phenyl substituents at position 2 are approximately orthogonal to each other, forming a dihedral angle of 81.04 (4)°. The crystal structure is stabilized by an intramolecular C—H...O hydrogen bond and by C—H...π interactions.

Intracrystalline Diffusion of Benzene in Ga-Silicate

1991

Abstract The sorption kinetics of benzene in large Ga-MFI crystals was investigated under constant volume- variable pressure conditions. A complete analysis of the uptake curves has been performed using solution of a nonlinear Volterra equation which describes the interaction of uptake process with the apparatus. Within the time scale of uptake measurements (10 3 -10 4 s) the uptake curves were found to be consistent with the solution of the second Fick's law. Corrected diffusion coefficients were found to be essentially independent of loading within the loading range investigated and in contrast to the system benzene-HNaZSM-5 [1,2] their temperature dependence is much stronger.

To be or not to be: Collaborative Governance and The Case of Continuous Master Planning in Lahti

2020

The benefits of collaborative actions between different stakeholders has been recognized broadly and has been admitted as one of the key factors in regional development. However, the research has so far focused on examining cases retrospectively, leaving a gap in looking into something on-going and uncertain, as well as it has been common to consider regional development through abstracts concepts. Therefore, there exists less information on the practical implementation of the theories and policies within regions. Additionally, it is important to take into consideration the ever-growing trend of cross-sectoral collaboration - however not only in public-private interface, but also involving …

Zvaigžņotā Debess: 2004/05, Ziema

2004

Contents: Ņ.Ozoliņa. Earthquakes in Latvia ; I.Daube. Space Craft “Ranger-7” ; M. Gailis. Moon Investigation in Riga ; J.Tambergs. Problems of Dialogue between Quantum Mechanics and Theology (concluded) ; Z Alksne, A.Alksnis. Ultra-Cool Dwarf Pair Weighed ; A.Balklavs. Successful Hunt of Protostars ; A.Balklavs. Silhouette of a Black Hole ; A.Balklavs. A Distant Giant Quasar ; A.Balklavs. Cosmic Objects in Captivating Photos – 3 ; J.Freimanis. Extragalactic Planetary Nebulae ; J.Jaunbergs. Cassini Enters the Saturnian System ; D.Krieviņš. Space Launchers of Early XXI Century. The Commonwealth of Independent States (CIS) ; J.Bārzdiņš. Professor Rusins-Martins Freivalds on the Path of Science…

Seasonal dependence in the solar neutrino flux

1999

MSW solutions of the solar neutrino problem predict a seasonal dependence of the zenith angle distribution of the event rates, due to the non-zero latitude at the Super-Kamiokande site. We calculate this seasonal dependence and compare it with the expectations in the no-oscillation case as well as just-so scenario, in the light of the latest Super-Kamiokande 708-day data. The seasonal dependence can be sizeable in the large mixing angle MSW solution and would be correlated with the day-night effect. This may be used to discriminate between MSW and just-so scenarios and should be taken into account in refined fits of the data.

Zenith angle distributions at Super-Kamiokande and SNO and the solution of the solar neutrino problem

2000

We have performed a detailed study of the zenith angle dependence of the regeneration factor and distributions of events at SNO and SK for different solutions of the solar neutrino problem. In particular, we discuss oscillatory behaviour and the synchronization effect in the distribution for the LMA solution, the parametric peak for the LOW solution, etc.. Physical interpretation of the effects is given. We suggest a new binning of events which emphasizes distinctive features of zenith angle distributions for the different solutions. We also find the correlations between the integrated day-night asymmetry and the rates of events in different zenith angle bins. Study of these correlations st…

Proton-air cross section measurement with the ARGO-YBJ cosmic ray experiment

2009

The proton-air cross section in the energy range 1-100 TeV has been measured by the ARGO-YBJ cosmic ray experiment. The analysis is based on the flux attenuation for different atmospheric depths (i.e. zenith angles) and exploits the detector capabilities of selecting the shower development stage by means of hit multiplicity, density and lateral profile measurements at ground. The effects of shower fluctuations, the contribution of heavier primaries and the uncertainties of the hadronic interaction models, have been taken into account. The results have been used to estimate the total proton-proton cross section at center of mass energies between 70 and 500 GeV, where no accelerator data are …

Lateral distribution of muons in IceCube cosmic ray events

2013

In cosmic ray air showers, the muon lateral separation from the center of the shower is a measure of the transverse momentum that the muon parent acquired in the cosmic ray interaction. IceCube has observed cosmic ray interactions that produce muons laterally separated by up to 400 m from the shower core, a factor of 6 larger distance than previous measurements. These muons originate in high pT (>2  GeV/c) interactions from the incident cosmic ray, or high-energy secondary interactions. The separation distribution shows a transition to a power law at large values, indicating the presence of a hard pT component that can be described by perturbative quantum chromodynamics. However, the ra…