CRYOGENIC GREASE LUBRICANTS FOR ROCKET AND SPACE TECHNOLOGY

2021 ◽  
pp. 31-41
Author(s):  
Andrey D. PLOTNIKOV ◽  
Aleksandr V. VODOLAZHSKIY ◽  
Natalya S. YAKUPOVA
Keyword(s):  
Chemical Composition ◽  
Low Temperature ◽  
Key Words ◽  
Ir Spectrum ◽  
Practical Relevance ◽  
Space Technology ◽  
Potential Evaporation ◽  
Testing Methods ◽  
Solidification Temperature ◽  
Temperature Characteristics

The paper represents requirements for cryogenic grease lubricants used in the rocket and space technology. Data on lubricants based on perfluoropolyether liquid FEN is provided. New lubricant testing methods enabling to analyze their chemical composition and low-temperature characteristics are proposed. Quoted are investigation results for the equivalents of previously used cryogenic lubricants NIKA, NIRA and «Ametist». A practical relevance of the paper has been proven by introduction of low-temperature lubricants «Sever» currently being used in rocket and space items, as well аs successful application of the developed lubricant incoming inspection procedures at RSC Energia. Key words: low-temperature lubricant, perfluoropolyether liquid FEN, viscosity, solidification temperature, IR spectrum, potential evaporation.

Effect of nitrogen fertilization on yield, storage losses and chemical composition of winter cabbage

1991 ◽  
Vol 71 (3) ◽  
pp. 943-946 ◽  
Author(s):  
S. Freyman ◽  
P. M. Toivonen ◽  
W. C. Lin ◽  
P. W. Perrin ◽  
J. W. Hall
Keyword(s):  
Ascorbic Acid ◽  
Chemical Composition ◽  
Key Words ◽  
Nitrogen Fertilization ◽  
N Fertilization ◽  
Nitrogen Rate ◽  
N Application ◽  
Storage Losses ◽  
White Cabbage ◽  
Brassica Oleracea L

Increasing rates of field nitrogen (N) application (0, 100, 200, 300, 400 and 500 kg N ha−1) resulted in markedly higher yields of winter white cabbage (Brassica oleracea L. var. capitata 'Bartolo') due to larger head size. Glucose and fructose contents increased with increased nitrogen. In contrast, ascorbic acid and sucrose contents declined slightly with increased nitrogen. Nitrogen rate had little effect on storage losses. The results indicated that increased N fertilization provided overall benefit to cabbage production. Key words: Cabbage, nitrogen fertilization, storage losses, yield

Low-temperature characteristics of 0.35 µm AlSb/InAs HEMTs

1994 ◽  
Vol 30 (16) ◽  
pp. 1358-1359 ◽  
Author(s):  
W. Kruppa ◽  
J.B. Boos
Keyword(s):  
Low Temperature ◽  
Temperature Characteristics

Silyubum marianum, dandelion plants and their benefits

2021 ◽  
Vol 08 (03) ◽  
pp. 16-19
Author(s):  
Gülüstan Nağı qızı Əliyeva ◽  
Keyword(s):  
Chemical Composition ◽  
Key Words ◽  
Scientific Article ◽  
The World ◽  
Therapeutic Properties

The scientific article provides detailed information about silyubum marianum and dandelion. Their chemical composition, therapeutic properties against liver, bile and other diseases, and their use in cosmetology were discussed. The article also discusses the benefits of silymarin in the treatment of cancer and osteoporosis. The components of silyubum marianum and dandelion plants have been announced. Distribution zones of silyubum marianum and dandelion plants in the world and in Azerbaijan have been noted. The rules of use of plants are also reflected in the article. Key words: plant, silyumarin, thorns, liver, seeds, silibinin.Carduelis,carotene

Effect of Chemical Composition of Welding Wire and Low Temperature Steel Plate on the Weld Properties Made by SAW

2008 ◽  
Vol 580-582 ◽  
pp. 57-60
Author(s):  
Hee Joon Sung ◽  
Yeon Baeg Goo ◽  
Kyeong Ju Kim ◽  
Kee Young Choi
Keyword(s):  
Chemical Composition ◽  
Low Temperature ◽  
Weld Metal ◽  
Steel Plate ◽  
Butt Joint ◽  
Welding Wire ◽  
High Hardenability ◽  
Weld Metals ◽  
Weld Properties ◽  
Mo Content

Chemical composition effect on the weld properties for low temperature steel was evaluated. The alloy elements of interest at the weld metal were Cr and Mo, which come from the steel plate and welding wire, respectively. Both side one run SAW process was carried out in a Ygroove butt joint. Microstructure of the weld metal is strongly dependent on the chemical composition of the steel plate and the welding wire, due to high dilution. The microstructure of the weld metal became fine acicular ferrite by increasing Cr and Mo content because of high hardenability effect. The weld metal having Cr and Mo possessed the highest impact toughness at low temperatures among the weld metals studied. Cr seems to have more effect than Mo on the toughness of the weld metal.

scholarly journals Formation of Intermediate Phases and Supersaturated Solid Solution in Al-Cu System during Diffusion

2018 ◽  
Vol 383 ◽  
pp. 31-35 ◽  
Author(s):  
Alexey Rodin ◽  
Nataliya Goreslavets
Keyword(s):  
Phase Diagram ◽  
Solid Solution ◽  
High Temperature ◽  
Chemical Composition ◽  
Low Temperature ◽  
Supersaturated Solid Solution ◽  
Diffusion Processes ◽  
Equilibrium Phase ◽  
Equilibrium Phase Diagram ◽  
Intermediate Phases

The study of diffusion processes in the aluminum - copper system was carried out at the temperature 350 and 520 °C. Special attention was paid on the chemical composition of the system near Al/Cu interface. It was determined that the intermediate phases in the system, corresponding to the equilibrium phase diagram, were not formed at low temperature. At high temperature the intermediate phases forms starting with Cu - rich phases. In both cases supersaturated solid solution of copper in aluminum could be observed near the interface.

CAD/CAM Zirconia for Dental Application

2013 ◽  
Vol 320 ◽  
pp. 505-511
Author(s):  
Ning Li ◽  
Zhi Kai Wu ◽  
Chao Jian ◽  
Wan Qian Zhao ◽  
Jia Zhen Yan
Keyword(s):  
Mechanical Properties ◽  
Low Temperature ◽  
Key Words ◽  
20Th Century ◽  
Dental Materials ◽  
Tetragonal Zirconia ◽  
Dental Application ◽  
Cad Cam ◽  
Low Temperature Aging ◽  
Temperature Aging

During the 20th century, both dental materials and dental technologies for the fabrication of dental prosthesis progressed remarkably. Owing to the increased demand of safety and aesthetics, 3 mol% yttria stabilized tetragonal zirconia polycrystalline has been recently introduced in prosthetic dentistry for the fabrication of crowns and fixed partial dentures, in combination with CAD/CAM technique. This greatly changed the conventional dental laboratory work which is labor-intensive and experience-dependent. This review mainly introduced the state of dental zirconia and the application of CAD/CAM technology in dentistry. Key words: Dental Zirconia; CAD/CAM Technique; Mechanical Properties; Transformation Toughing; Low Temperature Aging;

EFFECT OF SOIL ORGANIC MATTER OXIDATION ON THE COLLAPSE OF VERMICULITE

1985 ◽  
Vol 65 (3) ◽  
pp. 593-597 ◽  
Author(s):  
N. M. MILES ◽  
M. SCHNITZER ◽  
C. R. DE KIMPE
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Key Words ◽  
Mixed Layer ◽  
Ir Spectrum ◽  
X Ray Diffraction ◽  
X Ray ◽  
Organic Matter Oxidation ◽  
Ir Spectrophotometry ◽  
Complete Collapse

Oxidation of organic matter with H2O2 produced substantial amounts of NH3 which was then fixed by vermiculite, causing partial or complete collapse and converting the mineral to a mica-like product. The collapse of the mineral was indicated by shifts in the 001 spacing from 1.476 to 1.030 nm and the appearance of a well-defined band at 1430 cm−1 in the IR spectrum, indicative of the presence of NH4+ in the interlayer positions of the clay. Our data suggest that: (a) the transformation of vermiculite to mica during H2O2 oxidation may result in underestimation of the vermiculite content of soils by XRD, and (b) the wide occurrence of mixed-layer minerals in soils may in part have resulted from the fixation of NH3 liberated from the microbial mineralization of organically bound N. Key words: Ammonia, X-ray diffraction, IR spectrophotometry, mixed-layer minerals, H2O2 pretreatment

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