Multiphysics modeling of environment assisted cracking of buried pipelines in contact with solutions of near-neutral pH

Abstract: This paper provides a perspective on the stress corrosion cracking (SCC) of buried pipelines based on a paper by R.N. Parkins, et al., and associated works. The paper by Parkins, et al., included an identification of factors controlling near-neutral pH SCC (NNPHSCC) and a probabilistic approach to evaluating multiple cracks. Considerable research since the publication of the paper has shed light on the mechanisms of NNPHSCC and the various contributing factors. However, a probabilistic framework advanced by this paper is still a work in progress. This perspective describes the progress that has been made and the gaps still remaining in this area.

Download Full-text

Examination of Rabbit Fc Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100445 ◽

1968 ◽

Vol 26 ◽

pp. 140-141

Author(s):

J. P. Robinson ◽

P. G. Lenhert

Keyword(s):

Molecular Weight ◽

Flat Plate ◽

Phosphate Buffer ◽

Asymmetric Unit ◽

X Ray Diffraction ◽

X Ray ◽

Neutral Ph ◽

Small Crystals ◽

Carbon Coated ◽

Diffraction Patterns

Crystallographic studies of rabbit Fc using X-ray diffraction patterns were recently reported. The unit cell constants were reported to be a = 69. 2 A°, b = 73. 1 A°, c = 60. 6 A°, B = 104° 30', space group P21, monoclinic, volume of asymmetric unit V = 148, 000 A°3. The molecular weight of the fragment was determined to be 55, 000 ± 2000 which is in agreement with earlier determinations by other methods.Fc crystals were formed in water or dilute phosphate buffer at neutral pH. The resulting crystal was a flat plate as previously described. Preparations of small crystals were negatively stained by mixing the suspension with equal volumes of 2% silicotungstate at neutral pH. A drop of the mixture was placed on a carbon coated grid and allowed to stand for a few minutes. The excess liquid was removed and the grid was immediately put in the microscope.

Download Full-text

Multiphysics modeling of nuclear reactors

AccessScience ◽

10.1036/1097-8542.yb150702 ◽

2017 ◽

Keyword(s):

Nuclear Reactors ◽

Multiphysics Modeling

Download Full-text

Reaction of Acetaldehyde with Human Platelets

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648393 ◽

1992 ◽

Vol 67 (01) ◽

pp. 126-130 ◽

Cited By ~ 8

Author(s):

Olivier Spertini ◽

Jacques Hauert ◽

Fedor Bachmann

Keyword(s):

Platelet Aggregation ◽

Inhibitory Action ◽

Ex Vivo ◽

Platelet Rich Plasma ◽

Shape Change ◽

Reaction Medium ◽

Human Platelets ◽

Membrane Glycoproteins ◽

Neutral Ph

SummaryPlatelet function defects observed in chronic alcoholics are not wholly explained by the inhibitory action of ethanol on platelet aggregation; they are not completely reproduced either in vivo by short-term ethanol perfusion into volunteers or in vitro by the addition of ethanol to platelet-rich plasma. As acetaldehyde (AcH) binds to many proteins and impairs cellular activities, we investigated the effect of this early degradation product of ethanol on platelets. AcH formed adducts with human platelets at neutral pH at 37° C which were stable to extensive washing, trichloracetic acid hydrolysis and heating at 100° C, and were not reduced by sodium borohydride. The amount of platelet adducts formed was a function of the incubation time and of the concentration of AcH in the reaction medium. At low AcH concentrations (<0.2 mM), platelet bound AcH was directly proportional to the concentration of AcH in the reaction medium. At higher concentrations (≥0.2 mM), AcH uptake by platelets tended to reach a plateau. The amount of adducts was also proportional to the number of exposures of platelets to pulses of 20 pM AcH.AcH adducts formation severely impaired platelet aggregation and shape change induced by ADP, collagen and thrombin. A positive correlation was established between platelet-bound AcH and inhibition of aggregation.SDS-PAGE analysis of AcH adducts at neutral pH demonstrated the binding of [14C]acetaldehyde to many platelet proteins. AcH adduct formation with membrane glycoproteins, cytoskeleton and enzymes might interfere with several steps of platelet activation and impair platelet aggregation.This in vitro study shows that AcH has a major inhibitory action on platelet aggregation and may account for the prolonged ex vivo inhibition of aggregation observed in chronic alcoholics even in the absence of alcoholemia.

Download Full-text

Preparation, Stabilization and Some Properties of Purified Human Plasmin*

Thrombosis and Haemostasis ◽

10.1055/s-0038-1654807 ◽

1964 ◽

Vol 11 (01) ◽

pp. 075-084 ◽

Cited By ~ 2

Author(s):

Daniel L Kline ◽

Jacob B Fishman ◽

Keyword(s):

Plasminogen Activator ◽

Stable Form ◽

Neutral Ph ◽

The Stability ◽

And Storage

Summary1. Lysine increased the solubility, decreased the SK requirement and increased the stability of plasmin prepared from purified plasminogen by SK activation.2. A procedure is presented for the rapid and quantitative conversion of plasminogen to plasmin and storage of the plasmin in stable form at neutral pH as a lyophilized powder.3. Approximately 10% for the plasminogen molecule was split off during its activation. No carbohydrate was lost.4. The plasmin isolated was homogeneous in the ultracentrifuge at pH 2.5 and was quantitatively convertible to plasminogen activator by the addition of SK.

Download Full-text

Fibrinolytic Activity of Lung and Spleen Extracts Observed in Conventional but not in Germ-Free Rats

Thrombosis and Haemostasis ◽

10.1055/s-0038-1666910 ◽

1979 ◽

Vol 42 (02) ◽

pp. 726-733 ◽

Cited By ~ 1

Author(s):

Utako Okamoto ◽

Jun-ichiro Yamamoto ◽

Yoko Nagamatsu ◽

Noboru Horie

Keyword(s):

Serine Protease ◽

Plasminogen Activator ◽

Fibrinolytic Activity ◽

Iodoacetic Acid ◽

Thrombin Inhibitor ◽

Rat Tissues ◽

Germ Free ◽

Neutral Ph ◽

Tissue Extracts

SummaryProtease-like activity which split plasminogen-free fibrin was demonstrated in 2 M KSCN extracts of the lung and spleen of conventional rats. The activity was virtually undetectable in tissue extracts from germ-free rats. The extracts from the conventional rat tissues split fibrin and fibrinogen remarkably at neutral pH, but not casein, when examined using fibrin, fibrinogen-agar and casein-agar plates. The fibrinolytic activity was inhibited by STI and DFP, indicating a serine protease nature. The activity was not inhibited by TLCK, t-AMCHA or dansyl-L-arginine-methylpiperidine amide (a selective synthetic thrombin inhibitor, OM189). It was neither activated nor inhibited by cysteine, KCN or iodoacetic acid. The results obtained indicate that the protease-like activity of the lung and spleen extracted with 2 M KSCN from conventional rats has properties which differ from those of trypsin, plasmin, plasminogen-activator, thrombin, and cathepsin A, B and C.

Download Full-text