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  • SPACECRAFT PROPULSION AND POWER  (3)
  • honeybee  (3)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 44 (1988), S. 270-271 
    ISSN: 1420-9071
    Keywords: Pheromone ; social behavior ; honeybee
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary o-Aminoacetophenone is a pheromone produced by virgin honeybee queens and released with feces. In small social groups, the pheromone repels and is used to terminate agonistic interactions between queens and workers.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 45 (1989), S. 765-767 
    ISSN: 1420-9071
    Keywords: Social behavior ; honeybee ; division of labor ; behavior genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Recent studies have demonstrated a genotypic component to the division of labor among worker honeybees. However, these studies used artificially-selected strains of bees or colonies derived from queens that were instrumentally inseminated with the semen from very few males. We present evidence for genotypic variability among groups of workers performing tasks in colonies with naturally-mated queens. These results demonstrate that genetic structure is a level of social organization in honeybees.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 18 (1992), S. 1633-1640 
    ISSN: 1573-1561
    Keywords: Apis mellifera ; honeybee ; Hymenoptera ; Apidae ; queen ; fecal ; pheromones ; esters ; kin recognition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Previous work has shown that queen honeybees,Apis mellifera, produce waxy esters composed of 8–14 carbon acids and 6–14 carbon alcohols in their feces. We tested these esters for effects on nestmate recognition; 11 of the 12 esters tested significantly modified the recognition characteristics of worker honeybees. Pairwise tests showed that workers can discriminate between at least some pairs of queen esters and that workers can discriminate between a queen ester and hexadecane (another known nestmate recognition cue). These results suggest that a queen may use the esters to enable workers to recognize her or to scent-mark her colony.
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  • 4
    Publication Date: 2019-06-28
    Description: A generalized modeling program was adapted in BASIC on a personal computer to compare the performance of four types of biowaste resistojets and two types of hydrazine augmenters. Analyzed biowaste design types were: (1) an electrically conductive ceramic heater-exchanger of zirconia; (2) a truss heater of platinum in cross flow; (3) an immersed bicoiled tubular heater-exchanger; and (4) a nonexposed, refractory metal, radiant heater in a central cavity within a heat exchanger case. Concepts 2 and 3 are designed to have an efficient, stainless steel outer pressure case. The hydrazine design types are: (5) an immersed bicoil heater exchanger and (6) a nonexposed radiant heater now with a refractory metal case. The ceramic biowaste resistojet has the highest specific impulse growth potential at 2000 K of 192.5 (CO2) and 269 s (H2O). The bicoil produces the highest augmenter temperature of 1994 K for a 2073 K heater giving 317 s at .73 overall efficiency. Detailed temperature profiles of each of the designs are shown. The scaled layout drawings of each are presented with recommended materials and fabrication methods.
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: NASA-CR-179510 , NAS 1.26:179510
    Format: application/pdf
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  • 5
    Publication Date: 2019-06-28
    Description: The feasibility of fabricating small rhenium parts with metal oxide additives by means of slip casting and extrusion techniques is described. The metal oxides, ZrO2 and HfO2 were stabilized into the cubic phase with Y2O3. Additions of metal oxide to the rhenium of up to 15 weight percent were used. Tubes of 17 mm diameter with 0.5 mm walls were slip cast by adapting current ceramic oxide techniques. A complete cast double conical nozzle demonstrated the ability to meet shapes and tolerances. Extrusion of meter long tubing lengths of 3.9 mm o.d. x 2.3 mm i.d. final dimension is documented. Sintering schedules are presented to produce better than 95% of theoretical density parts. Finished machining was found possible were requried by electric discharge machining and diamond grinding.
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: NASA-CR-174970 , NAS 1.26:174970
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  • 6
    Publication Date: 2019-07-13
    Description: A 150 mlb thrust level hybrid resistojet which may operate on either H2 or NH3 is described whose design technique allows temperature distribution forecasting by means of a microcomputer-implemented mathematical model. The longer computer run times that accompany the exclusive use of BASIC, relative to assembled languages, are offset by the flexibility offered and the reduction of reprogramming and debugging efforts. The integration of a compact first-stage coiled heater with a concentric tubular gas heater offers direct matching of the 28 V terminal of the spacecraft system, while keeping maximum heater wall temperatures to less than 60 K over that of the gas temperature at the throat. Among the novel materials employed are grain-stabilized rhenium for heating elements and high purity aluminas for insulators.
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: AIAA PAPER 82-1949 , Japan Society for Aeronautical and Space Sciences, and DGLR, International Electric Propulsion Conference; Nov 17, 1982 - Nov 19, 1982; New Orleans, LA
    Format: text
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