Accelerated Aging Test and Study of Storage Life Prediction of NBR O-Ring

2011 ◽  
Vol 415-417 ◽  
pp. 184-190 ◽  
Author(s):  
Jun Pan ◽  
Shi Wei Xu ◽  
Wen Hua Chen ◽  
Xiao Yun Wang ◽  
Ping Qian ◽  
...  
Keyword(s):  
Accelerated Aging ◽  
Least Square Method ◽  
Storage Conditions ◽  
Storage Life ◽  
Least Square ◽  
Butadiene Rubber ◽  
Accelerated Aging Test ◽  
Aging Test ◽  
Servo Mechanism ◽  
Hydraulic Servo

Nitrile Butadiene Rubber (NBR) is a kind of common sealing materials for the electric hydraulic servo mechanism, there exists the aging failure problem in its storage environment, which is the key factor determining the storage life of the electric hydraulic servo mechanism. Through the analysis of aging failure mechanism of the NBR o-ring, the degradation path that varies with the changes of aging time based on compression set was established. And the Arrhenius equation, which is the acceleration equation of the aging reaction velocity varies with the changes of temperature, was established as well. In order to obtain the related parameters of the model, the accelerated aging test was conducted and its data were processed by applying the approximation standards and least square method. Also through the test the prediction of storage life of NBR o-ring under special storage conditions was made, and its predicted results were basically identical with the actual storage life.

scholarly journals Controlled Deterioration and Accelerated Aging Tests to Estimate the Relative Storage Potential of Cucurbit Seed Lots

HortScience ◽  
2008 ◽  
Vol 43 (5) ◽  
pp. 1544-1548 ◽  
Author(s):  
Ibrahim Demir ◽  
Kazim Mavi
Keyword(s):  
Moisture Content ◽  
Correlation Coefficient ◽  
Accelerated Aging ◽  
Aluminum Foil ◽  
Storage Conditions ◽  
Test Results ◽  
Accelerated Aging Test ◽  
Aging Test ◽  
Radicle Emergence ◽  
Controlled Deterioration

The laboratory germination (radicle emergence) percentages of 9 watermelon, 12 melon, and 7 cucumber seed lots were tested after storing in relatively adverse storage conditions of 25 °C and 12% mc for 6, 12, and 18 months in sealed aluminum foil packets. The laboratory germination (radicle emergence) of lots was determined after controlled deterioration (CD) at 45 °C with 20% or 24% moisture content (mc) for 48, 72, 96, 120, and 144 h. The accelerated aging test (AA) was conducted at 45 °C for the same aging periods. A number of seed lots was dead by 12 and 18 months in watermelon and cucumber, respectively. Various combinations of test regimens were found to be correlated with laboratory germination after 6 months storage, but the most consistent regimens for AA tests was 96 h at 45 °C in all species (r = 0.71 to 0.98). In the CD tests, 72 h with 20% mc at 45 °C gave the best correlation (r = 0.86 to 0.96). These conditions of highest correlation were observed after laboratory germination after 6 months storage and are suggested as good predictors of storage life in cucurbit seed lots. The initial standard germination before storage was also significantly correlated with seed longevity, but the correlation coefficient was generally lower (r = 0.60 to 0.83) than the AA and CD test results and separation of lots less clear.

Accelerated aging test of hydrogenated nitrile butadiene rubber using the time–temperature–strain superposition principle

RSC Advances ◽  
2015 ◽  
Vol 5 (109) ◽  
pp. 90178-90183 ◽  
Author(s):  
Zhongmeng Zhu ◽  
Chengkai Jiang ◽  
Qian Cheng ◽  
Jianwei Zhang ◽  
Shaoyun Guo ◽  
...  
Keyword(s):  
Fracture Strain ◽  
Superposition Principle ◽  
Accelerated Aging ◽  
Butadiene Rubber ◽  
Test Results ◽  
Short Term ◽  
Accelerated Aging Test ◽  
Aging Test ◽  
Temperature Strain

The long-term (~550 days) degradation of fracture strain of HNBR under the reference condition of 60 °C @ zero strain can be predicted using the time–temperature–strain superposition principle with the short-term (<10 days) test results.

scholarly journals Genetic diversity for physiological quality of seeds from corn (Zea mays L.) intervarietal crossbreeds

2013 ◽  
Vol 35 (4) ◽  
pp. 449-456 ◽  
Author(s):  
Daniele Nerling ◽  
Cileide Maria Medeiros Coelho ◽  
Rubens Onofre Nodari
Keyword(s):  
Genetic Diversity ◽  
Zea Mays L ◽  
Accelerated Aging ◽  
Genetic Contribution ◽  
Percentage Germination ◽  
Canonical Variables ◽  
Accelerated Aging Test ◽  
Aging Test ◽  
Physiological Quality

The physiological quality is based on the genotype and may be accompanied since the first stages of selection through the study of genetic diversity. The purpose of this study was to evaluate the parental genetic contribution in the seed physiological quality in corn intervarietal crossbreeds. The intervarietal crossbreeds were performed using landraces genotypes, open pollinated varieties and commercial hybrids. The seeds obtained from the crossbreed, their equivalents and parentals were evaluated regarding their water percentage, germination, germination speed rate, accelerated aging, field emergence and electrical conductivity. The seeds obtained in the crossbreed are viable and vivid with heterosis when compared with the parentals. The accelerated aging test was more effective for selecting the strongest genotypes. The canonical variables were useful to group the genotypes that presented similar physiological characteristics. The genotypes MPA 01 x Pixurum 05, MPA 01 x AS1565, MPA 01 x SJC5886, SJC5886 x Pixurum 05 and Fundacep 35 x SCS 154 Fortuna were the best crossbreeds regarding the production of better physiological quality seeds.

scholarly journals Accelerated aging test in amaranth (Amaranthus cruentus L.) seeds

2018 ◽  
Vol 12 (03) ◽  
pp. 444-448
Author(s):  
Andréa Bicca Noguez Martins ◽  
◽  
Caroline Jácome Costa ◽  
Fernanda da Motta Xavier ◽  
André Pich Brunes ◽  
...  
Keyword(s):  
Accelerated Aging ◽  
Amaranthus Cruentus ◽  
Accelerated Aging Test ◽  
Aging Test

scholarly journals Electrical conductivity and accelerated aging in amaranth (Amaranthus crueentus L.) seeds

2018 ◽  
Vol 40 (1) ◽  
pp. 44-51
Author(s):  
Thaís D’Avila Rosa ◽  
Ariele Paula Nadal ◽  
Henrique Roberto Maldaner ◽  
Vanessa Nogueira Soares ◽  
Gizele Ingrid Gadotti ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Accelerated Aging ◽  
Water Volume ◽  
Amaranthus Cruentus ◽  
Accelerated Aging Test ◽  
Aging Test ◽  
Immersion Period ◽  
Amaranth Seed

Abstract: The objective of this study was to determine adequate conditions of water volume, seed quantity and immersion period to perform the electrical conductivity test, and to analyze the parameters of the accelerated aging test and its correlation with the the physiological potential of amaranth seeds. Five lots of amaranth seeds (Amaranthus cruentus), cultivar BRS Alegria, were used. The initial evaluation of the quality of these lots comprehended the following tests: water content, germination, first germination count, accelerated aging (traditional method, and modified versions, using unsaturated and saturated saline solution for the periods of 24, 48 and 72 h), electrical conductivity in different periods (2, 4, 6, 8 and 24 h), different quantities of water (25, 50 and 75 mL), different seed quantities (100 and 150), and field emergence. It could be concluded that the accelerated aging test at 41 °C, for 72 h, using unsaturated NaCl solution was efficient in the classification of amaranth seed lots in levels of vigor. The electrical conductivity test performed for 8 hours with 25 mL of water and 100 seeds was efficient in the classification of amaranth seeds as to their physiological potential.

scholarly journals INTEMPERISMO ARTIFICIAL DE QUATRO REVESTIMENTOS APLICADOS EM MADEIRAS DE DUAS ESPÉCIES FLORESTAIS

Nativa ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 313 ◽  
Author(s):  
Aline Krolow Soares ◽  
Roberto Lessa Pereira ◽  
Pedro Henrique Gonzalez de Cademartori ◽  
Henrique Weber Dalla Costa ◽  
Darci Alberto Gatto
Keyword(s):  
Morphological Changes ◽  
Eucalyptus Grandis ◽  
Accelerated Aging ◽  
Surface Wettability ◽  
Forest Species ◽  
Artificial Weathering ◽  
Color Changes ◽  
Accelerated Aging Test ◽  
Aging Test ◽  
Weathering Resistance

O presente estudo teve como objetivo investigar a resistência ao intemperismo artificial de quatro revestimentos aplicados nas madeiras de duas espécies florestais. Para tal, foram utilizadas seis árvores de Eucalyptus grandis e três árvores de Tetrorchidium rubrivenium as quais foram desdobradas para confecção de 50 amostras para cada espécie, com dimensões de 5,0x7,0x1,0cm (largura, comprimento e espessura, respectivamente). A superfície das madeiras foi revestida com quatro acabamentos: polistein, verniz marítimo, tinta branca base óleo e tinta branca base água. As amostras sem revestimento e revestidas foram submetidas ao ensaio de envelhecimento acelerado durante 480 horas. A resistência ao intemperismo artificial foi avaliada por meio das modificações colorimétricas e morfológicas ao longo da exposição das madeiras e em função da molhabilidade superficial. Os principais resultados mostraram que a superfície das madeiras  tendeu a tons opacos após exposição de 480 horas. Foi observado que os revestimentos não evitaram o aumento da molhabilidade superficial. Após todo o período de exposição, as madeiras não apresentaram modificações morfológicas tais como rachaduras e descascamento dos revestimentos, o que denota importante característica de proteção à madeira.Palavras-chave: Eucalyptus, canemaçu, modificação da superfície, envelhecimento acelerado, durabilidade da madeira. ARTIFICIAL WEATHERING OF FOUR COATINGS APPLIED ON WOODS OF TWO FOREST SPECIES ABSTRACT:The present study aimed to investigate the resistance to artificial weathering of four coatings applied on wood from two forest species. Six trees of Eucalyptus grandis and three trees of Tetrorchidium rubrivenium were cut to produce 50 wood samples for each species with dimensions of 5.0x7.0x1.0 cm (width, length and thickness, respectively). Wood surface was coated with four finishing products: polistein, marine varnish, oil-based white paint and water-based white paint. The uncoated and coated wood samples were subjected to accelerated aging test for 480h. The artificial weathering resistance was evaluated by color changes and surface wettability. The main results showed the coated woods tend to opaque tones after the exposure for 480h. The coatings did not avoid the increase of the surface wettability. After the exposure, both woods did not present morphological changes, such as cracks and peeling into the coatings, which represent relevant characteristics for wood protection.Keywords: Eucalyptus, canemaçu, surface modification, accelerated aging, wood durability. DOI:

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