scholarly journals Prime focus imaging spectrograph for the Southern African large telescope: operational modes

2003 ◽  
Author(s):  
Henry A. Kobulnicky ◽  
Kenneth H. Nordsieck ◽  
Eric B. Burgh ◽  
Michael P. Smith ◽  
Jeffrey W. Percival ◽  
...  
Keyword(s):  
Large Telescope ◽  
Operational Modes ◽  
Imaging Spectrograph

Prime Focus Imaging Spectrograph for the Southern African Large Telescope: optical design

2003 ◽  
Author(s):  
Eric B. Burgh ◽  
Kenneth H. Nordsieck ◽  
Henry A. Kobulnicky ◽  
Ted B. Williams ◽  
Darragh O'Donoghue ◽  
...  
Keyword(s):  
Optical Design ◽  
Large Telescope ◽  
Imaging Spectrograph

scholarly journals The Far Ultraviolet Imaging Spectrograph on Spartan-281

1990 ◽  
Vol 139 ◽  
pp. 459-460
Author(s):  
George R. Carruthers ◽  
Harry M. Heckathorn ◽  
John C. Raymond ◽  
Reginald J. Dufour ◽  
Adolf N. Witt ◽  
...  
Keyword(s):  
Spectral Range ◽  
Angular Resolution ◽  
Hubble Space Telescope ◽  
Compact Objects ◽  
High Angular Resolution ◽  
Large Telescope ◽  
International Ultraviolet Explorer ◽  
Far Ultraviolet ◽  
Compact Sources ◽  
Imaging Spectrograph

The study of diffuse celestial sources in the ground-inaccessible ultraviolet spectral range is less advanced than UV studies of point and compact sources. The main reason is that the characteristics of instrumentation optimized for the two types of objects are quite different. Studies of diffuse objects are best made with fast focal ratio optics with wide fields of view, whereas studies of point and compact objects are best made with large telescope aperture and high angular resolution. As a result, most space ultraviolet instruments to date (such as the International Ultraviolet Explorer and the forthcoming Hubble Space Telescope) are not well suited to the study of faint, extended diffuse objects in the ultraviolet.

The prime focus imaging spectrograph for the Southern African Large Telescope: structural and mechanical design and commissioning

2006 ◽  
Author(s):  
Michael P. Smith ◽  
Kenneth H. Nordsieck ◽  
Eric B. Burgh ◽  
Jeffrey W. Percival ◽  
T. B. Williams ◽  
...  
Keyword(s):  
Mechanical Design ◽  
Large Telescope ◽  
Imaging Spectrograph

B. Large Telescope Engineering Operations

1966 ◽  
Vol 27 ◽  
pp. 200-209
Keyword(s):  
Large Telescope ◽  
Advance Planning

Whitford : The next phase of the program has to do with advance planning of the instruments themselves, to make the logistics of operation simple and foolproof. I call first on Mr Rule to speak on ‘thinking ahead’.

A New Detector System For The HB5 Stem Instrument

1985 ◽  
Vol 43 ◽  
pp. 134-135
Author(s):  
J.M. Cowley
Keyword(s):  
Dark Field ◽  
Detector System ◽  
Electron Holography ◽  
Small Specimen ◽  
Bright Field ◽  
Multiple Images ◽  
Practical Applications ◽  
Wide Range ◽  
Diffraction Patterns ◽  
Operational Modes

The HB5 STEM instrument at ASU has been modified previously to include an efficient two-dimensional detector incorporating an optical analyser device and also a digital system for the recording of multiple images. The detector system was built to explore a wide range of possibilities including in-line electron holography, the observation and recording of diffraction patterns from very small specimen regions (having diameters as small as 3Å) and the formation of both bright field and dark field images by detection of various portions of the diffraction pattern. Experience in the use of this system has shown that sane of its capabilities are unique and valuable. For other purposes it appears that, while the principles of the operational modes may be verified, the practical applications are limited by the details of the initial design.

Efficiency of two-stage heating of water on CHP plant with turbines of type T-250/300-240

2019 ◽  
Vol 12 (3) ◽  
pp. 213-219
Author(s):  
E. T. Ilin ◽  
S. P. Pechenkin ◽  
A. V. Svetushkov ◽  
J. A. Kozlova
Keyword(s):  
Transition Period ◽  
Steam Pressure ◽  
Low Pressure ◽  
Heat Extraction ◽  
Two Stage ◽  
Permissible Level ◽  
Lower Heat ◽  
Operational Modes ◽  
Extraction Section ◽  
Supply Water

During non-heating and transition period, most of cogeneration turbines operate with a lower heat extraction section actuated only due to a number of restrictions on the maximum and minimum pressure levels in the upper and lower heat extraction sections at operation of the turbine. For turbines of model T-250/300-240, the minimum permissible level of steam pressure in the upper heat extraction section, according to manufacturer data, is set to 0.06 MPa. During the non-heating and transition period, the supply water temperature is usually set in the range of 70–75°С. In order to maintain that temperature of supply water, the steam pressure in the upper heat extraction section should be below the minimum permissible level. As a result, the turbine operates with only the low-pressure heat extraction section actuated, which ensures operation without restrictions, but with a lower efficiency. The authors have introduced a set of measures, which enable to avoid those restrictions and implement two-stage heating of supply water. In this case, on connection of the upper heating extraction section, the pressure in the same is maintained at the minimum permissible level. Heat output characteristics are provided by having some of supply water delivered bypassing the group of network heaters. This operational mode enables to increase the turbine actual heat drop, to reduce the cooling steam flow into the low-pressure section and, accordingly, into the condenser, and to reduce temperature drops in network water heaters. Results of the research of operational modes for turbines of type T-250/300-240 in the non-heating and transition period with one and two-stage heating are provided. The economic efficiency of proposed operational modes was researched, which shows the effectiveness of those modes during non-heating and transition period. The limits of the efficiency of using these modes are determined.

Effect of increased temperatures on structures of titanium VT22 alloy strengthened by electromechanical processing

2020 ◽  
pp. 376-379
Author(s):  
S.A. Yakovlev ◽  
M.M. Zamal’dinov ◽  
A.A. Glushchenko ◽  
I.R. Salakhutdinov
Keyword(s):  
Titanium Alloys ◽  
Heating Temperature ◽  
Alloy Vt22 ◽  
Vt22 Alloy ◽  
Machine Parts ◽  
Operational Modes

The hardening methods of titanium alloys are analyzed. Effect of heating temperature on resistance of VT22 alloy structures strengthened by electromechanical processing is defined. Results of change in hardness of the strengthened structures depending on heating temperature are presented. Recommendations on the operational modes of machine parts made of alloy VT22 strengthened by electromechanical processing are provided.

Effect of operational modes on the removal of a synthetic organic chemical by powdered activated carbon during ultrafiltration

2001 ◽  
Vol 1 (5-6) ◽  
pp. 39-47
Author(s):  
Y. Matsui ◽  
A. Yuasa ◽  
F. Colas
Keyword(s):  
Activated Carbon ◽  
Cross Flow ◽  
Powdered Activated Carbon ◽  
Organic Chemical ◽  
Filtration Cycle ◽  
Dead End ◽  
Synthetic Organic Chemical ◽  
The Cross ◽  
Short Time ◽  
Operational Modes

The effects of operational modes on the removal of a synthetic organic chemical (SOC) in natural water by powdered activated carbon (PAC) during ultrafiltration (UF) were studied, through model simulations and experiments. The removal percentage of the trace SOC was independent of its influent concentration for a given PAC dose. The minimum PAC dosage required to achieve a desired effluent concentration could quickly be optimized from the C/C0 plot as a function of the PAC dosage. The cross-flow operation was not advantageous over the dead-end regarding the SOC removal. Added PAC was re-circulated as a suspension in the UF loop for only a short time even under the cross-flow velocity of gt; 1.0 m/s. The cross-flow condition did not contribute much to the suspending of PAC. The pulse PAC addition at the beginning of a filtration cycle resulted in somewhat better SOC removal than the continuous PAC addition. The increased NOM loading on PAC which was dosed in a pulse and stayed longer in the UF loop could possibly further decrease the adsorption rate.

Experience from 10 Years Advanced Wastewater Treatment – Technology and Results

1982 ◽  
Vol 14 (1-2) ◽  
pp. 121-133
Author(s):  
C Forsberg ◽  
B Hawerman ◽  
B Hultman
Keyword(s):  
Wastewater Treatment ◽  
Urban Population ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Municipal Wastewater Treatment ◽  
Treatment Technology ◽  
Removal Efficiencies ◽  
Municipal Wastewater Treatment Plants ◽  
Operational Modes ◽  
Polluted Waters

Experience from advanced municipal wastewater treatment plants and recovery of polluted waters are described for the last ten years in Sweden. Except in municipalities with large recipients, the urban population is served by treatment plants with combined biological and chemical treatment. Most of these plants are post-precipitation plants. Several modified operational modes have been developed in order to improve the removal efficiencies of pollutants and to reduce the costs. Results are presented on the recovery of specially investigated lakes with a lowered supply of total phosphorus and organic matter.

Growth Characteristics of Activated Sludges Acclimated to para-Nitrophenol in Batch and Continuous Modes

1994 ◽  
Vol 29 (7) ◽  
pp. 327-333
Author(s):  
Y. Matsui ◽  
F. Yamaguchi ◽  
Y. Suwa ◽  
Y. Urushigawa
Keyword(s):  
Growth Characteristics ◽  
The Other ◽  
Operational Mode ◽  
Continuous Mode ◽  
Relative Resistance ◽  
Batch Mode ◽  
The Given ◽  
Operational Modes ◽  
Very High ◽  
Sensitive Group

Activated sludges were acclimated to p-nitrophenol (PNP) in two operational modes, a batch and a continuous. The operational mode of the PNP acclimation of activated sludges strongly affected the physiological characteristics of predominant microorganisms responsible for PNP degradation. Predominant PNP degraders in the sludge in batch mode (Sludge B) had lower PNP affinity and were relatively insensitive to PNP concentration. Those of the sludge in continuous mode (Sludge C), on the other hand, had very high PNP affinity and were sensitive to PNP. MPN enumeration of PNP degraders in sludge B and C using media with different PNP concentrations (0.05, 0.2,0.5 and 2.0 mM) supported the above results. Medium with 0.2 mM of PNP did not recover PNP degraders in sludge C well, while it recovered PNP degraders in sludge B as well as the medium with 0.05 mM did. When switching from one operational mode to the other, the predominant population in sludge B shifted to the sensitive group, but that of sludge C did not shift at the given loading of PNP, showing relative resistance to inhibitive concentration.

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