A search is made for bursts of low-energy (20-60 MeV) neutrino interactions, signaling stellar core collapse, in a large underground water- Cerenkov detector. Over a period of 5.6 years (2.1 live ...years) no bursts were observed. A 90 percent confidence-level (CL) upper limit to the rate of stellar collapse in the galaxy is set at less than 1.5/yr. A limit of less than 1.1 stellar collapses per year (90 percent CL) is set for a smaller volume of the Galaxy (10 kpc radius) which includes the galactic center and more than 50 percent of the stars in the Milky Way. (Author)
For the design and construction of prestressed concrete reactor vessels, data on loading, construction materials, and safety factors are required. A description is given of the design conditions ...according to the current state of technology in the Federal Republic of Germany. Special consideration is given to the allowable stresses and an appropriate proposal for such stresses is suggested.
Far infrared, infrared and Raman spectra of tin hexathiohypodiphosphate Sn
(monoclinic modification II) have been recorded. The observed frequencies are assigned on the basis of P
units with C
...symmetry in the crystal. The assignment is supported by the correlation D
(dissolved P
ion) → C
. DTA-data have been determined and interpreted.
Far infrared, infrared and Raman spectra of tin hexathiohypodiphosphate Sn
2
P
2
S
6
(monoclinic modification II) have been recorded. The observed frequencies are assigned on the basis of P
2
S
6
4-
...units with C
2h
symmetry in the crystal. The assignment is supported by the correlation D
3d
(dissolved P
2
S
6
4-
ion) → C
2h
. DTA-data have been determined and interpreted.
Further stringent emission legislation requires advanced technologies, such as sophisticated engine management and advanced catalyst and substrate to achieve high catalytic performance, especially ...during the light-off phase. This paper presents the results of calculations and measurements of hydrocarbon and carbon monoxide light-off performance for substrates of different wall thickness, cell density and cell shapes. The experimental data from catalyst light-off testing on an engine dynamometer are compared with theoretical results of computer modeling under different temperature ramps and flow rates. The reaction kinetics in the computer modeling are derived from the best fit for the performance of conventional ceramic substrate (6mil/400cpsi), by comparing the theoretical and experimental results on both HC and CO emissions. The calibrated computer model predicts the effects of different wall thickness, cell density and cell shape. Different cell shapes, Triangle, Square, and Hexagon, are chosen as typical cell shapes used in the market. The substrates that are tested have the same Geometric Surface Area (GSA) on the basis of bare substrate, providing a fair basis of comparison . Furthermore, the influence of material properties on light-off performance is studied.
We investigate the matching behaviour of poly-silicon resistors. Experimental results from an analog CMOS process with three poly-silicon options are discussed and compared with a quantitative model ...which is developed using fit parameter-free analytical calculations and Monte-Carlo simulations. It is found that mismatch is directly proportional to the grain size. A relation is derived that allows us to optimize devices for low mismatch circuit applications.
