TMAE vapour of CsI layers as photocathodes in a multiwire proportional counter working at atmospheric pressure

Most of the measurements reported here have been obtained with the 4.5-L CO2 counter previously described (Kiel I; Erlenkeuser, 1965). A few samples have been dated with a 3-L proportional counter. The copper counter is surrounded by 28 GM counters in the form of a double ring. The total assembly is shielded by 10 cm of old lead. Neither an inner lead shield between counter and anticoincidence ring nor screening of sensitive volume by a quartz tube-as in the 4.5-L counter-has been used. Background of the small counter is 17.20 cpm or The 0.95 x NBS value is 9.5 cpm at 400 torr. Within statistical error background does not depend on atmospheric pressure. The 3-L counter is placed under a concrete wall, 2.5 m in length and 9.4 m in height.

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Surface-extended x-ray-absorption fine-structure experiments at atmospheric pressure by means of a photocathode proportional counter with monolayer sensitivity

Physical Review B ◽

10.1103/physrevb.39.10651 ◽

1989 ◽

Vol 39 (15) ◽

pp. 10651-10657 ◽

Cited By ~ 9

Author(s):

G. G. Long ◽

D. A. Fischer ◽

J. Kruger ◽

D. R. Black ◽

D. K. Tanaka ◽

...

Keyword(s):

Fine Structure ◽

Proportional Counter ◽

Atmospheric Pressure ◽

X Ray ◽

Absorption Fine ◽

X Ray Absorption

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CHEMICAL STATE ANALYSIS OF Cr AND Fe BY IN-AIR PIXE USING A CURVED CRYSTAL SPECTROMETER COMBINED WITH A POSITION-SENSITIVE PROPORTIONAL COUNTER

International Journal of PIXE ◽

10.1142/s0129083505000246 ◽

2005 ◽

Vol 15 (01n02) ◽

pp. 1-9

Author(s):

KUNIKO MAEDA ◽

KENICHI HASEGAWA ◽

HIROMI HAMANAKA ◽

KIYOSHI OGIWARA ◽

MASAMICHI TSUJI ◽

...

Keyword(s):

Proportional Counter ◽

Atmospheric Pressure ◽

Chemical State ◽

Transition Elements ◽

Measuring Time ◽

Crystal Spectrometer ◽

Chemical States ◽

Position Sensitive ◽

Fine Structures ◽

State Analysis

The feasibility of RIKEN high-resolution PIXE system for direct chemical state analysis of 3d transition elements was examined. K β spectra of Cr and Fe from several compounds were measured in air at atmospheric pressure using a crystal spectrometer consisting of a position-sensitive proportional counter and a curved crystal in v. Hamos geometry. Fine structures which reflect the chemical states of Cr and Fe were well recognized with the measuring time of tens minutes.

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Large-area proportional counter

Canadian Journal of Physics ◽

10.1139/p68-431 ◽

1968 ◽

Vol 46 (10) ◽

pp. S1112-S1115

Author(s):

S. Higashi ◽

T. Kitamuea ◽

S. Miono ◽

M. Nakagawa ◽

S. Ozaki ◽

...

Keyword(s):

Proportional Counter ◽

Atmospheric Pressure ◽

Large Scale ◽

Large Area ◽

Proportional Counters

The properties of proportional counters have been studied using a model of size 2 × 2 m2 and 10 cm deep filled with PR gas at atmospheric pressure. These counters were found to be useful for constructing large-scale detectors with uniform sensitivity over large areas, such as 2 × 2 m2 or more.

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A High-Voltage Terminal for a Field-Emission Gun

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009539x ◽

1972 ◽

Vol 30 ◽

pp. 428-429

Author(s):

N. F. Ziegler

Keyword(s):

Field Emission ◽

High Voltage ◽

Atmospheric Pressure ◽

Power Supplies ◽

High Coherence

A high-voltage terminal has been constructed for housing the various power supplies and metering circuits required by the field-emission gun (described elsewhere in these Proceedings) for the high-coherence microscope. The terminal is cylindrical in shape having a diameter of 14 inches and a length of 24 inches. It is completely enclosed by an aluminum housing filled with Freon-12 gas at essentially atmospheric pressure. The potential of the terminal relative to ground is, of course, equal to the accelerating potential of the microscope, which in the present case, is 150 kilovolts maximum.

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Electron microscope characterization of MOCVD-grown gap layers on Si

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144991 ◽

1986 ◽

Vol 44 ◽

pp. 724-725

Author(s):

K.M. Jones ◽

M.M. Al-Jassim ◽

J.M. Olson

Keyword(s):

Atmospheric Pressure ◽

Vapour Deposition ◽

Chemical Vapour ◽

Organic Chemical ◽

Lattice Match ◽

Si Substrates ◽

Metal Organic ◽

Good Lattice ◽

Antiphase Domains

The epitaxial growth of III-V semiconductors on Si for integrated optoelectronic applications is currently of great interest. GaP, with a lattice constant close to that of Si, is an attractive buffer between Si and, for example, GaAsP. In spite of the good lattice match, the growth of device quality GaP on Si is not without difficulty. The formation of antiphase domains, the difficulty in cleaning the Si substrates prior to growth, and the poor layer morphology are some of the problems encountered. In this work, the structural perfection of GaP layers was investigated as a function of several process variables including growth rate and temperature, and Si substrate orientation. The GaP layers were grown in an atmospheric pressure metal organic chemical vapour deposition (MOCVD) system using trimethylgallium and phosphine in H2. The Si substrates orientations used were (100), 2° off (100) towards (110), (111) and (211).

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Microstructure and reactivity of small metal particles: The role of Ce additives

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121995 ◽

1992 ◽

Vol 50 (1) ◽

pp. 318-319

Author(s):

L.D. Schmidt ◽

K. R. Krause ◽

J. M. Schwartz ◽

X. Chu

Keyword(s):

Atmospheric Pressure ◽

Noble Metals ◽

Mixed Oxides ◽

Catalytic Properties ◽

Chemical Shifts ◽

Catalytic Converter ◽

Structural Evolution ◽

Single Particles ◽

Small Metal Particles

The evolution of microstructures of 10- to 100-Å diameter particles of Rh and Pt on SiO2 and Al2O3 following treatment in reducing, oxidizing, and reacting conditions have been characterized by TEM. We are able to transfer particles repeatedly between microscope and a reactor furnace so that the structural evolution of single particles can be examined following treatments in gases at atmospheric pressure. We are especially interested in the role of Ce additives on noble metals such as Pt and Rh. These systems are crucial in the automotive catalytic converter, and rare earths can significantly modify catalytic properties in many reactions. In particular, we are concerned with the oxidation state of Ce and its role in formation of mixed oxides with metals or with the support. For this we employ EELS in TEM, a technique uniquely suited to detect chemical shifts with ∼30Å resolution.

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