85 research outputs found
Simulation von Nachhallzeit und Energie-Verlauf mit einem neuen nichtstatistischen Computermodell
Effect of Pore Geometry on Ultra-Densified Hydrogen in Microporous Carbons
This is the final version. Available on open access from Elsevier via the DOI in this recordOur investigations into molecular hydrogen (H2) confined in microporous carbons with
different pore geometries at 77 K have provided detailed information on effects of pore shape on
densification of confined H2 at pressures up to 15 MPa. We selected three materials: a disordered,
phenolic resin-based activated carbon, a graphitic carbon with slit-shaped pores (titanium carbidederived carbon), and single-walled carbon nanotubes, all with comparable pore sizes of < 1 nm.
We show via a combination of in situ inelastic neutron scattering studies, high-pressure H2
adsorption measurements, and molecular modelling that both slit-shaped and cylindrical pores
with a diameter of ~0.7 nm lead to significant H2 densification compared to bulk hydrogen under
the same conditions, with only subtle differences in hydrogen packing (and hence density) due to
geometric constraints. While pore geometry may play some part in influencing the diffusion
kinetics and packing arrangement of hydrogen molecules in pores, pore size remains the critical
factor determining hydrogen storage capacities. This confirmation of the effects of pore geometry
and pore size on the confinement of molecules is essential in understanding and guiding the
development and scale-up of porous adsorbents that are tailored for maximising H2 storage
capacities, in particular for sustainable energy applications.Engineering and Physical Sciences Research Council (EPSRC
A Search for Selectrons and Squarks at HERA
Data from electron-proton collisions at a center-of-mass energy of 300 GeV
are used for a search for selectrons and squarks within the framework of the
minimal supersymmetric model. The decays of selectrons and squarks into the
lightest supersymmetric particle lead to final states with an electron and
hadrons accompanied by large missing energy and transverse momentum. No signal
is found and new bounds on the existence of these particles are derived. At 95%
confidence level the excluded region extends to 65 GeV for selectron and squark
masses, and to 40 GeV for the mass of the lightest supersymmetric particle.Comment: 13 pages, latex, 6 Figure
A Re-Evaluation of the nuclear Structure Function Ratios for D, He, Li, C and Ca
We present a re-evaluation of the structure function ratios F2(He)/F2(D),
F2(C)/F2(D) and F2(Ca)/F2(D) measured in deep inelastic muon-nucleus scattering
at an incident muon momentum of 200 GeV. We also present the ratios
F2(C)/F2(Li), F2(Ca)/F2(Li) and F2(Ca)/F2(C) measured at 90 GeV. The results
are based on data already published by NMC; the main difference in the analysis
is a correction for the masses of the deuterium targets and an improvement in
the radiative corrections. The kinematic range covered is 0.0035 < x < 0.65,
0.5 < Q^2 <90 GeV^2 for the He/D, C/D and Ca/D data and 0.0085 < x < 0.6, 0.84
< Q^2 < 17 GeV^2 for the Li/C/Ca ones.Comment: 6 pages, Latex, 3 figures as uuencoded compressed tar file included
at the end, in case of problems contact [email protected] (Antje
Bruell
A Measurement of the Proton Structure Function
A measurement of the proton structure function is reported
for momentum transfer squared between 4.5 and 1600 and
for Bjorken between and 0.13 using data collected by the
HERA experiment H1 in 1993. It is observed that increases
significantly with decreasing , confirming our previous measurement made
with one tenth of the data available in this analysis. The dependence is
approximately logarithmic over the full kinematic range covered. The subsample
of deep inelastic events with a large pseudo-rapidity gap in the hadronic
energy flow close to the proton remnant is used to measure the "diffractive"
contribution to .Comment: 32 pages, ps, appended as compressed, uuencoded fil
Korporatsioon Fraternitas Tartuensise ja korporatsiooni Amicitia ühise tantsukursuse lõpuõhtu 1934. a.
http://www.ester.ee/record=b4609661*es
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