Environmental Testing of High Tc Superconductive Thermal Isolators for Space-Borne Cryogenic Detector Systems

1992 ◽  
Vol 275 ◽  
Author(s):  
Stephanie A. Wise ◽  
John D. Buckley ◽  
Henry W. Randolf ◽  
Darren Verbelyi ◽  
Gene H. Haertling ◽  
...  

ABSTRACTNASA's requirements for space-based cryogenic detector systems include the long-term storage of the liquid helium cryogen necessary for the optimized performance of far-infrared (IR) detectors. Significant heat loads on the liquid helium dewars exist due to the numerous electrical connections to the detectors, accounting for approximately 20 percent of the total heat load for some systems. High temperature superconductor lead assemblies are under development to replace the existing manganin wires connecting instruments at 80 K to the detector array at 4.2 K. These superconductive elements provide adequate current transport properties, while decreasing the thermal load on the liquid helium dewar. As a result, mission lifetimes can be extended by 10 percent or more.Thick films of the superconductive material on low thermal conductivity substrates (e.g. yttria stabilized zirconia and fused silica) have been proposed to replace the existing lead assemblies. This work describes some of the design constraints on such a device as well as preliminary analyses of the effects of vibration, gamma irradiation, and long term exposure to high vacuum and liquid nitrogen encountered in operating such a device in space.

Author(s):  
Allen Angel ◽  
Kathryn A. Jakes

Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.


2001 ◽  
Vol 6 (2) ◽  
pp. 3-14 ◽  
Author(s):  
R. Baronas ◽  
F. Ivanauskas ◽  
I. Juodeikienė ◽  
A. Kajalavičius

A model of moisture movement in wood is presented in this paper in a two-dimensional-in-space formulation. The finite-difference technique has been used in order to obtain the solution of the problem. The model was applied to predict the moisture content in sawn boards from pine during long term storage under outdoor climatic conditions. The satisfactory agreement between the numerical solution and experimental data was obtained.


Diabetes ◽  
1997 ◽  
Vol 46 (3) ◽  
pp. 519-523 ◽  
Author(s):  
G. M. Beattie ◽  
J. H. Crowe ◽  
A. D. Lopez ◽  
V. Cirulli ◽  
C. Ricordi ◽  
...  

2020 ◽  
Vol 59 (SL) ◽  
pp. SLLC01 ◽  
Author(s):  
Tomoki Murota ◽  
Toshiki Mimura ◽  
Ploybussara Gomasang ◽  
Shinji Yokogawa ◽  
Kazuyoshi Ueno

Author(s):  
S.V. Chernobai ◽  
V.K. Riabchun ◽  
T.B. Kapustina ◽  
V.S. Melnyk ◽  
O.E. Shchechenko

Goal. To build up a spring triticale genetic bank to provide breeding, scientific and educational institutions with initial material and to preserve the existing diversity. To update the database of accessions with a set of valuable economic and morphological features. Results and discussion. The methodology and results of the collection formation and evaluation of spring triticale accessions in the National Center for Plant Genetic Resources of Ukraine of Plant Production Institute nd. a V. Ya. Yuriev are presented. The formed collection includes 1,935 accessions from 27 countries: 42 varieties and 1,478 breeding lines from Ukraine, 92 varieties and 248 lines from foreign countries and also 75 genetic lines. The collection was formed by major valuable economic features (plant height, growing season length, spike threshing, yield, 1000-grain weight, disease resistance, technological properties, etc.). Accessions with the majority of morpho-biological and valuable economic features were selected. All the accessions in the collection are certificated. 1,762 accessions were packed for storage into the National Depository; 1,507 of them were packed for long-term storage. Conclusions. The gene pool of spring triticale from the collection of the Gene Bank of Plants of Ukraine is widely used for breeding. This allows conducting hybridization of genetically and ecologically remote forms with various expressions of features and obtaining whole new breeding material. Involvement of collection accessions in breeding allows generating new genetic sources of valuable economic features.


2011 ◽  
pp. 85-89 ◽  
Author(s):  
Giorgio Pezzi

No real improvement in the technological quality of beet has been recorded over the last 15 years in Northern Italy. Among the possible explanations for the quality stagnation is that the traditional formulae cannot correctly differentiate between sugarbeet varieties which produce thick juice of very high purity. This seems to be connected with the role of potassium. The use of a standard purification procedure gives reliable and accurate data which is immediately comparable with the factory data. Research projects on medium/long term storage are currently being performed by Co.Pro.B., Italy, in cooperation with Syngenta and Beta. Up to now the results have shown that storage of sugarbeet in autumn time in northern Italy is possible provided that suitable varieties and proper handling of the roots are employed. Results obtained in the storage trials are reported. Correlations have been found between quality parameters (purity, color and lime salts) of the purified juice with the glucose content of the raw juice. An interesting correlation is reported between purified juice purity and raw juice purity.


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