The concept of Ms and derivation of the reference stress solutions of API579-1/ASME FFS-1 Fitness-For-Service Part 9 were developed through past 50 years with variety of papers. The idea of those ...reference stress solutions of Part 9 are also rooted to the basis of Part 5 Local Metal Loss Assessment. It is important to understand the derivation of those solutions to conduct fitness-for-service correctly. A paper that explain those concept in a well-organized manner was awaited in the society. To address those expectations, ASME PVP 2020 21085 and 21086, SIGNIFICANCE OF MS AND VALIDATION OF REFERENCE STRESS SOLUTIONS FOR CRACK LIKE FLAWS were released in ASME PVP 2020. As Japanese refining and chemical industry shifts from new plant construction to pursuance of operational excellence of existing units for survival in the global market, Fitness-For-Service technology is considered as one of the key technology to achieve the operational excellence without sacrificing operational safety. Author hopes sharing the background of those reference stress solutions of API579-1/ASME FFS-1 in Japanese society would lead to a further enhancement of FFS technology discussion in this country. This is the 1st paper of the series.
The concept of Ms and derivation of the reference stress solutions of API579-1/ASME FFS-1 Fitness-For-Service Part 9 were developed through past 50 years with variety of papers. The idea of those ...reference stress solutions of Part 9 are also rooted to the basis of Part 5 Local Metal Loss Assessment. It is important to understand the derivation of those solutions to conduct fitness-for-service correctly. A paper that explain those concept in a well-organized manner was awaited in the society. To address those expectations, ASME PVP 2020 21085 and 21086, SIGNIFICANCE OF MS AND VALIDATION OF REFERENCE STRESS SOLUTIONS FOR CRACK LIKE FLAWS were released in ASME PVP 2020. As Japanese refining and chemical industry shifts from new plant construction to pursuance of operational excellence of existing units for survival in the global market, Fitness-For-Service technology is considered as one of the key technology to achieve the operational excellence without sacrificing operational safety. Author hopes sharing the background of those reference stress solutions of API579-1/ASME FFS-1 in Japanese society would lead to a further enhancement of FFS technology discussion in this country. This is the 2nd paper of the series.
The concept of Ms and derivation of the reference stress solutions of API579-1/ASME FFS-1 Fitness-For-Service Part 9 were developed through past 50 years with variety of papers. The idea of those ...reference stress solutions of Part 9 are also rooted to the basis of Part 5 Local Metal Loss Assessment. It is important to understand the derivation of those solutions to conduct fitness-for-service correctly. A paper that explain those concept in a well-organized manner was awaited in the society. To address those expectations, ASME PVP 2020 21085 and 21086, SIGNIFICANCE OF MS AND VALIDATION OF REFERENCE STRESS SOLUTIONS FOR CRACK LIKE FLAWS were released in ASME PVP 2020. As Japanese refining and chemical industry shifts from new plant construction to pursuance of operational excellence of existing units for survival in the global market, Fitness-For-Service technology is considered as one of the key technology to achieve the operational excellence without sacrificing operational safety. Author hopes sharing the background of those reference stress solutions of API579-1/ASME FFS-1 in Japanese society would lead to a further enhancement of FFS technology discussion in this country. This is the 3rd paper of the series and the discussion is concluded.
At the panicle formation stage, denitrification N loss in the rhizosphere soil was investigated in a pot experiment. A solution of ammonium-
15
N was injected with a syringe at a soil depth of 50 mm ...to distinguish the N losses between the surface and the rhizosphere soil. Denitrification process in the pots with plants ((+)Plant) was compared with that in pots where plants were cut off at the base of the culm ((−)Plant) to evaluate the effect of plant growth on the denitrification N loss. About 50% of the applied
15
N was absorbed by the plants during the first 2 d after fertilizer application (DAF) in the (+)Plant treatment. In the (−)Plant treatment, no
15
N absorbed by the plants after plant cutting. The amount of exchangeable NH
4
+
-
15
N in the 1st soil layer (0∓20 mm) was negligible throughout the experimental period in both treatments. The amount of immobilized
15
N in the (+)Plant treatment was larger than that in the (−)Plant treatment until 4 DAF. These results indicated that plant growth enhanced biological N fixation in soil during the first 4 DAF. The amount of denitrified
15
N estimated in the (−)Plant treatment (62% of applied N at 2 DAF and 21% at 4 DAF) was larger than that in the (+)Plant treatment (2.1% at 2 DAF and 3.5% at 4 DAF). The rate of suppression of the denitrification N loss (RSDN) by plants was 57% at 2 DAF and 17% at 4 DAF. The higher RSDN at 2 DAF in this experiment was mainly due to differences between the two treatments in the amounts of
15
N recovered by the plants and immobilized in soil. These results suggest that N absorption by the plants and N immobilization in soil reduced the denitrification N loss in the rhizosphere soil.
There is an increasing demand for evaluation of fracture toughness of long time used pressure vessels. This paper proposes a small-size specimen, which uses parallel laser welds of small-sample ...extracted from running vessels. The constraint effect by hard region of laser welds is strong enough to cause brittle fracture in the small-size specimen. Sometimes the constraint of laser welds in the small-size specimen is higher than that of the full-thick base metal specimen. To estimate the fracture toughness of the thick base metal specimen, this paper applies the local approach, which employs the Weibull stress as a fracture driving force of the material. It has been shown that the distribution of the critical Weibull stress at brittle fracture initiation for the small-size specimen with hard zones and homogeneous specimens are almost the same. This means that the critical Weibull stress is a material property independent of the specimen type. Based on the Weibull stress criterion, the fracture toughness of every thick base metal specimen is expected to be predicted from the fracture toughness results of the small-size specimen. The procedure proposed in this paper is useful to evaluate the fracture toughness of pressure vessels in service from the test results by small sample extracted from the vessels.
Astrocytes may function as mediators of the impact of noradrenaline on neuronal function. Activation of glial α1-adrenergic receptors triggers rapid astrocytic Ca
elevation and facilitates synaptic ...plasticity, while activation of β-adrenergic receptors elevates cAMP levels and modulates memory consolidation. However, the dynamics of these processes in behaving mice remain unexplored, as do the interactions between the distinct second messenger pathways. Here we simultaneously monitored astrocytic Ca
and cAMP and demonstrate that astrocytic second messengers are regulated in a temporally distinct manner. In behaving mice, we found that while an abrupt facial air puff triggered transient increases in noradrenaline release and large cytosolic astrocytic Ca
elevations, cAMP changes were not detectable. By contrast, repeated aversive stimuli that lead to prolonged periods of vigilance were accompanied by robust noradrenergic axonal activity and gradual sustained cAMP increases. Our findings suggest distinct astrocytic signaling pathways can integrate noradrenergic activity during vigilance states to mediate distinct functions supporting memory.
PDF
