Solenoid

About: Solenoid is a research topic. Over the lifetime, 19278 publications have been published within this topic receiving 114721 citations.

Precision measurement of the conversion electron spectrum of 83mKr with a solenoid retarding spectrometer

Abstract: This paper reports on precision measurements of conversion lines in the decay of83mKr with nuclear transition energies of 32.1 keV and 9.4 keV, respectively. The spectra were taken from a submonolayer surface of83m Kr frozen onto a cold backing, using the new Mainz solenoid retarding spectrometer. The high luminosity and resolution of this instrument enables the observation of all allowed conversion lines up to theN-shell and to fully separate the elastic component from inelastic satellites. The combined analysis of the data yields the transition energiesE y=32151.5±1.1 eV and 9405.9±0.8 eV, respectively. The experiment served also to pilot the application of this spectrometer to the question of a finite neutrino rest mass, searched for in theβ-decay spectrum of tritium and to problems in precision electron spectroscopy in general.

Coffee brewer with independent control of dispense period and batch quantity and method

Abstract: A coffee brewer ( 10, 10 ′ and 10 ′) is provided with a plurality of solenoid controlled, bi-position dispense valves ( 40, 40 ′), a size adjustable valve ( 60 ) or a combination of both and a programmable controller ( 18 ) for controlling the dispense valves in accordance with preselected brew parameters of batch quantity and dispense time duration (FIG. 8 ).

DM2, A Magnetic Detector for the Orsay Storage Ring DCI

Abstract: DM2 is the magnetic detector built to study e+e- interactions in the c.m. energy range 1.2-3.7 GeV with the Orsay Storage Ring DCI. The magnet is a solenoid of 2 m diameter and 3 m length with a conventional aluminium coil producing a 0.5 T field. Inside the coil, the charged particles detector is made of two proportional chambers with anode and cathode read-outs, 13 layers of drift chambers, one layer of water Cerenkov counters and one layer of scintillation counters. Photon detection is provided outside the 1 rad length coil by stacks of 14 planes of wire tubes with longitudinal read-outs, separated by lead sheets, and by five layers of scintillation counters. Inside the coil, the end caps are covered by shower detectors made of lead sheets and MWPC planes. Muon separation uses the flux return iron or concrete absorbers, and planes of wire tubes with longitudinal read-out. The charged particle detector covers 87% or 4π and the photon detector 82% of 4π. Charged particle identification by time of flight and Cerenkov radiation can discriminate pions from kaons up to 600 MeV/c and kaons from protons up to 1100 MeV/c. The photon detection efficiency is 50% at 50 MeV and near 100% at 100 MeV. It allows a neutral trigger to be operated. The detector is starting operation on the storage ring DCI at Orsay.

Plasma formation in START and MAST spherical tokamaks

Abstract: Different methods of plasma formation have been studied in spherical tokamaks (ST). In inductive methods, breakdown and formation of ST plasma are achieved through the application of an electric field produced by a rapid change of currents in poloidal field coils, in the central solenoid or by using internal electrodes. In non-inductive methods, breakdown and formation of ST plasma are achieved by the application of radio frequency (RF) power, neutral beam injection or other ionization and current drive techniques. A combination of these methods is often used. Inductive methods utilizing flux from the central solenoid have limited performance as there is limited space for the central solenoid in STs, so methods not using the central solenoid flux are of special interest. In this paper we discuss different methods developed and used on the START and MAST STs at Culham; in particular, direct induction and electron cyclotron resonance preionization assisted formation are discussed in detail. These experiments have been performed at different RF frequencies and results of these studies are compared with the theory. Other methods, for example, the merging–compression and the double-null merging, are mentioned and prospects of different formation methods for future STs are discussed.

Closed-loop idle speed control system for fuel-injected engines using pulse width modulation

Abstract: A closed loop idle speed controller for a fuel injection system operates to control an air valve which controls an air passage bypassing the main air flow. The air valve is positioned by an actuator whose output position is controlled by fuel pressure operating against a spring. The fuel pressure is controlled by a pair of solenoid-operated on-off valves, one of which responds to electrical signals representing engine speeds below a speed reference to direct fuel to the actuator and the other of which responds to signals representing speeds above the reference to permit fuel to be withdrawn from the actuator and returned to its source. Each of the solenoid on-off valves is supplied from a pulse width modulator. The engine-driven distributor provides pulses responsive to engine speed which are connected to a sample and hold circuit. The sample and hold circuit provides d.c. voltage levels proportional to engine rpm, modified with changes in engine coolant temperature, to a pair of summing amplifiers which compare the modified speed voltage with an idle speed reference voltage to produce speed error signals. Underspeed signals are connected to the pulse width modulator connected to the supply solenoid on-off valve and overspeed signals to the modulator connected to the return solenoid on-off valve. Certain auxiliary circuits provide for modified operation during starting, during hot starts, during closed throttle operation, or during deceleration with a manual transmission car.