Creep and rupture of an ods alloy with high stress rupture ductility

The creep and stress rupture properties of an oxide (Y₂O₃) dispersion strengthened nickel-base alloy, which also is strengthened by γ′ precipitates, was studied at 760 °C and 1093 °C. At both temperatures the alloy YDNiCrAl exhibits unusually high stress rupture ductility as measured by both elongation and reduction in area. Failure was transgranular, and different modes of failure were observed including crystallographic fracture at intermediate temperatures and tearing or necking almost to a chisel point at higher temperatures. While the rupture ductility was high, the creep strength of the alloy was low relative to conventional γ′ strengthened superalloys in the intermediate temperature range and to ODS alloys in the higher temperature range. These findings are discussed with respect to the alloy composition; the strengthening oxide phases, which are inhomogeneously dispersed; the grain morphology, which is coarse and elongated and exhibits many included grains; and the second phase inclusion particles occurring at grain boundaries and in the matrix. The creep properties, in particular the high stress dependencies and high creep activation energies measured, are discussed with respect to the resisting stress model of creep in particle strengthened alloys. RICHARD M. ARONS, formerly a Graduate Student at Columbia University     

Thermoplastic elastomer based on waste polyethylene/waste rubber containing activated carbon black: Impact of gamma irradiation

The effect of using gamma radiation on the prepared activated carbon (AC) from carbon black using dose 500 kGy was studied. Moreover, AC powder were blended in internal mixer to prepare thermoplastic elastomer with percentage (75/25/10) wt% based on waste polyethylene and waste rubber which irradiated before mixing at dose100 kGy separately and AC. Chemical activity of composites was improved as a result of using gamma radiation which was examined by electron spin resonance estimations. Composites were studied by different techniques, such as FTIR, mechanical, thermal, morphology, and X‐ray diffraction. The results indicated that optimistic effect of using gamma rays with improving the properties of the composites. J. VINYL ADDIT. TECHNOL., 25:E166–E176, 2019. © 2018 Society of Plastics Engineers     

Impact of gamma irradiation on virgin styrene butadiene rubber blended with ultrasonically devulcanized waste rubber

This investigation focused on the opportunity of devulcanizing waste Rubber (WR) by ultrasonication to study the possibility of utilized as an added substance to replace with styrene‐butadiene rubber (SBR) in preparation process with the final aim of preparation new composites. The present work expects to compare the ultrasonic technique and the previous work on devulcanization by mechano‐chemical method. The influence of the ultrasonication treatment on the WR was explored by Fourier transform infrared, thermogravimetric analysis, scanning electron microscopy analysis revealed that ultrasonication was observed to be the best factor impacting the devulcanization procedure, this procedure suggests that use of specific levels of ultrasonic waves to the vulcanized rubber with a specific aim to accomplish a particular breaking of compound connections: scission of C‐S and S‐S bonds without break carbon–carbon (C‐C) bonds. Various blends of devulcanized WR with SBR was treatments with gamma ray then investigated and compared with find out the rubber giving the highest compatibility for compounding and revulcanization. In addition, a comparison of these results was made with the ones of raw SBR rubber compound. POLYM. ENG. SCI., 59:807–813, 2019. © 2019 Society of Plastics Engineers     

Small-Molecule Inhibition of the uPAR ⋅ uPA Interaction by Conformational Selection

The urokinase receptor (uPAR) is a cell surface receptor that binds to the serine protease urokinase-type plasminogen activator (uPA) with high affinity. This interaction is beneficial for extravascular fibrin clearance, but it has also been associated with a broad range of pathological conditions including cancer, atherosclerosis, and kidney disease. Here, starting with a small molecule that we previously discovered by virtual screening and cheminformatics analysis, we design and synthesize several derivatives that were tested for binding and inhibition of the uPAR ⋅ uPA interaction. To confirm the binding site and establish a binding mode of the compounds, we carried out biophysical studies using uPAR mutants, among them uPAR^H47C−N259C, a mutant previously developed to mimic the structure of uPA-bound uPAR. Remarkably, a substantial increase in potency is observed for inhibition of uPAR^H47C−N259C binding to uPA compared to wild-type uPAR, consistent with our use of the structure of uPAR in its uPA-bound state to design small-molecule uPAR ⋅ uPA antagonists. Combined with the biophysical studies, molecular docking followed by extensive explicit-solvent molecular dynamics simulations and MM-GBSA free energy calculations yielded the most favorable binding pose of the compound. Collectively, these results suggest that potent inhibition of uPAR binding to uPA with small molecules will likely only be achieved by developing small molecules that exhibit high-affinity to solution apo structures of uPAR, rather than uPA-bound structures of the receptor.     

Analyzing the Variability in Low-Flow Projections under GCM CMIP5 Scenarios

Water Resources Management - The present study considered the impacts of global climate model (GCM) selection in the Couple Model Intercomparison Phase 5 (CMIP5) scenarios on the low-flow...     

Performance of RSS Based Cooperative Localization in Millimeter Wave Wireless Sensor Networks

Wireless Personal Communications - Localization in wireless sensor networks (WSNs) is a necessity as there is a vital need to have location information combined with the measured quantities. The...     

Accelerating video encoding using cluster computing

The great advance and variety of multimedia applications such as video streaming, TV broadcasting, and video conferencing stimulated research to enhance video encoding, where a video is reduced in size and possibly transformed to numerous formats for portability. This paper is concerned with solving the problem of the huge processing time taken by the serial video encoding approaches by proposing a hybrid-parallel video encoding technique to speed up the process. In this work, the Joint Scalable Video Model (JSVM 9.19.14) is chosen as the basic serial video encoding algorithm for building different parallel video encoding architectures. The proposed technique exploits the triple-step nature of JSVM and intelligently determines the best task organization to achieve speedup and increase the efficiency on a cluster computing platform. Moreover, a dynamic load sharing scheme is proposed to redistribute load among different machines for additional parallelism. The remarkable feature of our approach is that, both the granularity of load partitioning among the cluster machines and all the associated overheads are considered. The experimental results are applied on a compact library of 160 mp4 encoded videos and two other bench mark datasets. The results proves a significant improvement in performance in comparison to the sequential version; which ranges from 64.2% to 95.3%, for a cluster with a number of machines ranging from 2 to 20 respectively.

     

Prenatal exposure to the fluoride containing psychiatric drug fluoxetine and anti-oxidative alterations in the neonatal rat brain

Fluoride is a key ingredient of many psychiatric drugs like fluoxetine (Prozac^®, Fluoxetine^®). Pregnant women frequently use this drug as they suffer from depression and anxiety disorders during this period. Fluoxetine is able to reach the fetus through the placenta and passes to the newborn through milk. In the present study, female Wistar rats were treated with 5, 10, and 20 mg/L fluoxetine (containing 94% fluorides) from pregnancy day 10 to day 20. After delivery, the levels of the enzymatic antioxidants in the brain of their offspring at postnatal day 2 were measured. The results showed that, in all fluoxetine exposed groups compared with the control group, there was a significant decrease (P < 0.01) in the glutathione, catalase, glutathione S-transferases and potassium and a non- significant increase (P > 0.05) in the activity of malondialdehyde and creatine kinase. The results suggest that fluoxetine may be a developmental neurotoxicant due to presence of fluoride hence must be used carefully during pregnancy.