scispace - formally typeset
Search or ask a question

Showing papers by "Worcester Polytechnic Institute published in 1971"


Journal ArticleDOI
TL;DR: In this paper, the Bose-Einstein properties of a light beam scattered by a rotating ground glass with average-size inhomogeneities of approximately 1 μm were investigated.
Abstract: We report some experimental results concerning the statistical properties of a light beam scattered by a rotating ground glass with average-size inhomogeneities of approximately 1 μm. Photocount statistics measured at different scattering angles and for different angular velocities of the ground glass have confirmed the known result that the scattered-light amplitude is a stochastic gaussian variable. The Bose–Einstein nature of the photocount statistics has been verified with an accuracy of a few parts per thousand. Self-beating measurements on the scattered light of a He–Ne laser in a TEM00 configuration have shown that the power spectrum is a gaussian function of the frequency. The dependence of its half-width on the angular velocity of the ground glass and on the focal length of the lens that focuses the beam on the scattering surface has been measured. The experimental results agree very closely with our theoretical predictions.

111 citations


Journal ArticleDOI
TL;DR: The reaction of CCl4 with H2 over peripherally deposited Pt on η-Al2O3 catalyst proceeds as two parallel reactions, producing CHCl3 and CH4 at constant mole ratio, independent of process variables as mentioned in this paper.

83 citations




Journal ArticleDOI
TL;DR: Using variable temperature PMR spectroscopy and total PMR line shape analysis, the activation parameters for chair-chair interconversion in cyclopentamethylenedimethylsilane (E a = 6·1 + 0·3 kcal/mole) were determined in this paper.

21 citations



Journal ArticleDOI
TL;DR: In this article, a method of preparation of salts of the B 3 H 8 − ion from NaBH 4 and BF 3 -etherate is described which requires neither the use of high pressures nor the need to handle diborane.

13 citations


Journal ArticleDOI
TL;DR: In this paper, the vapor phase hydrogenation of 1-butene, catalyzed by nickel supported on mordenite and Types X and A molecular sieve (0.19 − 9.8, 1.67 and 2.71 wt % Ni), was studied in the temperature range 40 −135 °C.

13 citations


Journal ArticleDOI
TL;DR: In this article, a series of acid-leached, large-port hydrogen-exchanged mordenites ranging in alumina content (on anhydrous basis) from 11.2% (commercial Hex-mordenite) to 0.1% Al2O3 at both differential and integral conversions were measured.

10 citations


Journal ArticleDOI
TL;DR: The currentvoltage characteristics of metal-selenium diodes under small reverse bias are shown to be consistent with the Schottky rectification theory for a number of metals: Au, Ag, Sn, Pb, and In.
Abstract: The current-voltage characteristics of metal-selenium diodes under small reverse bias are shown to be consistent with the Schottky rectification theory for a number of metals: Au, Ag, Sn, Pb, and In. The characteristics have the correct voltage and temperature dependence and the magnitude of the reverse current is consistent with the known bulk transport parameters of polycrystalline selenium. There is no simple relationship between the barrier height and the metal work function, which is not surprising in view of the complicated chemistry of the interface and the fact that many contaminants are present. Im Bereiche kleiner Sperrspannungen konnen die Strom–Spannungskennlinien der Metall-Selen-Dioden fur Au, Ag, Sn, Pb und In durch die Gleichrichtertheorie von Schottky erklart werden. Die Kennlinien weisen die richtige Spannungs-und Temperaturabhangigkeit auf, und die Grose des Sperrstromes stimmt mit den bekannten Transportparametern von polykristallinem Selen uberein. Ein einfacher Zusammenhang zwischen Barrierenpotential und der Austrittsarbeit des Metalles existiert nicht, was wegen der komplizierten chemischen Eigenschaften der Grenzflache und der Anwesenheit vieler Fremddefekte nicht erstaunlich ist.

9 citations


Journal ArticleDOI
TL;DR: Ejected photoelectron count probability distribution due to periodic irradiance modulation of amplitude stabilized light beam was studied in this article, where the number of photoelectrons was proportional to the irradiance modulus of the light beam.
Abstract: Ejected photoelectron count probability distribution due to periodic irradiance modulation of amplitude stabilized light beam


Journal ArticleDOI
TL;DR: In this article, the authors obtained quivocal evidence for tert-butyl rotation in tert-butyldimethylamine (I) using dynamic NMR spectroscopy.



Journal ArticleDOI
TL;DR: In this article, the authors measured the breakdown field strength of holes in polycrystalline selenium as a function of temperature through the field dependence of photocurrent and showed that the breakdown process can be described in terms of the Wolff model of breakdown.
Abstract: Theionization coefficient for holes in polycrystalline selenium has been measured as a function of temperature through the field dependence of photocurrent. At 250 °K the breakdown field strength is approximately 2×105 V/cm decreasing to 1.5×105 V/cm at 156 °K. The phonon creation length is 100 A at 300 °K becoming larger as the temperature is decreased. The magnitudes of the breakdown fields and the phonon creation length indicate that the breakdown process can be described in terms of the Wolff model of breakdown. Die Temperaturabhangigkeit des Ionisationskoeffizienten fur Locher in polykristallinem Selen wurde durch die Feldabhangigkeit des Photostromes gemessen. Die Durchbruchspannung vermindert sich von 2×105 V/cm bei 250 °K bis zu 1,5×105 V/cm bei 156 °K. Die Weglange zur Erzeugung von Phononen ist 100 A fur 300 °K und nimmt mit abnehmender Temperatur zu. Die Grose des Durchbruchfeldes und der Erzeugungsweglange fur Phononen zeigen, das die Durchbruchsvorgange durch das Durchschlagsmodell von Wolff erklart werden konnen.


Journal ArticleDOI
TL;DR: An electromagnetic electrode driving device which produces a relatively pure axial motion has been developed and has been used to penetrate cells with a diameter of about 5 ?
Abstract: An electromagnetic electrode driving device which produces a relatively pure axial motion has been developed. The motion takes place in a few milliseconds, and its amplitude can be adjusted over a range of about ?-30 ?m. The device has been used to penetrate cells with a diameter of about 5 ?m.



Journal ArticleDOI
TL;DR: In this paper, it was shown that the lattice mobility of electrons in silicon is determined by high energy acoustic phonons (zero point scattering) rather than by optical phonons.

Journal ArticleDOI
TL;DR: In this article, the condenser cooling water of the James A. FitzPatrick Nuclear Power Plant, located on Lake Ontario, will be discharged through a submerged diffuser, which will consist of six pairs of nozzles, each 2.5 ft diam., connected by riser shafts to a tunnel excavated in bedrock under the lake bottom.
Abstract: To comply with New York State temperature criteria, the condenser cooling water of the James A. FitzPatrick Nuclear Power Plant, located on Lake Ontario, will be discharged through a submerged diffuser. The discharge structure will be located in an average water depth of 30 ft and will consist of six pairs of nozzles, each 2.5 ft diam., connected by riser shafts to a tunnel excavated in bedrock under the lake bottom. The cooling water intake will be sector-shaped and located shoreward of the line of nozzles. The designs of intake and discharge structures are based on hydraulic model studies. Data for the model studies were obtained from surveys in the lake aimed at defining natural wind-induced currents and temperature distributions.