ABSTRACT
The use of Pipelines for long-distance transportation of crude oil, natural gas and similar applications is increasing and has pivotal importance in recent times. High specific strength plays a crucial role in improving transport efficiency through increased pressure and improved laying efficiency through reduced diameter and weight of line pipes. TRIP-based high-strength and high-ductility alloys comprise a mixture of ferrite, bainite, and retained austenite that provide excellent mechanical properties such as dimensional stability, fatigue strength, and impact toughness. This study performs microstructure analysis using both Nital etching and LePera etching methods. At the time of Nital etching, it is difficult to distinctly observe second phase. However, using LePera etching conditions it is possible to distinctly measure the M/A phase and ferrite matrix. The fraction measurement was done using OM and SEM images which give similar results for the average volume fraction of the phases. Although it is possible to distinguish the M/A phase from the SEM image of the sample subjected to LePera etching. However, using Nital etching is nearly impossible. Nital etching is good at specific phase analysis than LePera etching when using SEM images.
ABSTRACT
This study shows an artificial neural network (ANN) model of chlorophenol rejection from aqueous solutions and predicting the performance of spiral wound reverse osmosis (SWRO) modules. This type of rejection shows complex non-linear dependencies on feed pressure, feed temperature, concentration, and feed flow rate. It provides a demanding test of the application of ANN model analysis to SWRO modules. The predictions are compared with experimental data obtained with SWRO modules. The overall agreement between the experimental and ANN model predicted was almost 99.9% accuracy for the chlorophenol rejection. The ANN model approach has the advantage of understanding the complex chlorophenol rejection phenomena as a function of SWRO process parameters.
Subject(s)
Chlorophenols , Water Purification , Filtration , Membranes, Artificial , OsmosisABSTRACT
AIM: Most heel pain occurs at the posterior or plantar aspect, where main entheses of the heel are located. However, simple radiographs as basic work-up tools, their features based on their association with local symptoms in the heel in ankylosing spondylitis (AS) patients, have rarely been described. METHOD: Forty patients with AS and unilateral heel pain were enrolled to evaluate radiographic differences between symptomatic and asymptomatic heels. The two groups were assessed according to symptom location: posterior (group PS) or plantar (group PL). Typical abnormalities in bone and/or soft tissue on the heel due to inflammation were compared. RESULTS: In group PS (20 cases), 19 (95%) symptomatic feet and 7 (35%) asymptomatic feet showed abnormal findings on the posterior heel and symptomatic feet showed 6 (30%) plantar abnormalities. Erosion of the posterior calcaneal tuberosity, obliteration of the retrocalcaneal recess (RR), and swelling shadows with increased thickness on posterior soft tissue were observed more frequently and significantly in symptomatic feet in group PS (P < 0.05). In group PL (20 cases), 11 (55%) symptomatic feet and 8 (40%) asymptomatic feet showed abnormalities on the plantar heel and symptomatic feet showed 14 (70%) posterior abnormalities, and none showed significant differences between symptomatic and asymptomatic feet. CONCLUSION: Among simple radiographic alterations on heels with AS, such changes around the enthesis of the Achilles as bony erosion and RR obliteration with swollen posterior soft tissue are strongly related to current painful posterior heels. Assessment of enthesitis of the Achilles tendon in AS using plain radiography seems to be valid.
