Study of the productivity of MWCNT over Fe and Fe–Co catalysts supported on SiO2, Al2O3 and MgO

AbstractIn the present study, multi-walled carbon nanotubes (MWCNT) were prepared in good quality and quantity, MWCNT were produced using the catalytic chemical vapor deposition (CCVD) technique and the carbon source was acetylene. Different catalysts were synthesized based on iron and a mixture of iron and cobalt metal supported on SiO2, Al2O3 or MgO. The effect of parameters such as iron concentration, support type, bimetallic catalyst and the method of catalyst preparation has been investigated in the production of MWCNT. The quality of as-made nanotubes was investigated by the high-resolution transmission electron microscopy (HRTEM) and thermogravimetric analysis (TGA). The best yield of MWCNT was 30 times of the amount of the used catalyst. The high yield of MWCNT was gained by 40wt.% Fe on alumina support which was prepared by the sol–gel method. TEM analysis was done for the carbon deposit, which revealed that the walls of the MWCNT were graphitized, with regular inner channel and uniform diameter. It reflected a reasonable degree of purity. The TGA showed that MWCNT was decomposed at 635°C by a small rate indicating a high thermal stability and well crystalline formation of the produced MWCNT

Computational Simulations of Magnetic Particle Capture in Arterial Flows

The aim of Magnetic Drug Targeting (MDT) is to concentrate drugs, attached to magnetic particles, in a specific part of the human body by applying a magnetic field. Computational simulations are performed of blood flow and magnetic particle motion in a left coronary artery and a carotid artery, using the properties of presently available magnetic carriers and strong superconducting magnets (up to B ≈ 2 T). For simple tube geometries it is deduced theoretically that the particle capture efficiency scales as \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\eta \sim \sqrt{{Mn}_{\rm p}}$$\end{document}, with Mnp the characteristic ratio of the particle magnetization force and the drag force. This relation is found to hold quite well for the carotid artery. For the coronary artery, the presence of side branches and domain curvature causes deviations from this scaling rule, viz. η ∼ Mnpβ, with β > 1/2. The simulations demonstrate that approximately a quarter of the inserted 4 μm particles can be captured from the bloodstream of the left coronary artery, when the magnet is placed at a distance of 4.25 cm. When the same magnet is placed at a distance of 1 cm from a carotid artery, almost all of the inserted 4 μm particles are captured. The performed simulations, therefore, reveal significant potential for the application of MDT to the treatment of atherosclerosis

Synthesis and characterization of polyurethane based on hydroxyl terminated polybutadiene and reinforced by carbon nanotubes

Nanocomposites consisting of multi wall carbon wall carbon nano tubes MWCNT/polyurethane (PU) had been successfully prepared based on hydroxy terminated polybutadiene HTPB and the prepared MWCNT. The effect of concentration of prepared MWCNT and surface modified CNT on the morphology, mechanical reinforcement, and thermal properties of PU-based composites had been evaluated by FESEM, tensile testing, thermo gravimetric analysis TGA and differential scanning calorimeter DSC. Polyurethane (PU) networks based on hydroxyl terminated polybutadiene (HTPB) and isophorone diisocyanate (IPDI) compound were prepared by a batch process. Two methods had been used to fabricate PU matrix/carbon nanotube nanocomposites: direct incorporation of unfunctional CNT (UCNT) into polymer matrices (noncovalent attachment) and in situ polymerization at their surface (covalent attachment). TGA showed a much better improvement of thermal stability of the composites than pure PU. Glass temperature (Tg) increased due to high interaction of CNT with PU. Also Young’s modulus increased. FESEM gave that the covalent attachment was better than noncovalent attachment for preparing PU/CNT composites

Correction to:Contemporary cemented versus uncemented hemiarthroplasty for the treatment of displaced intracapsular hip fractures: a meta-analysis of forty-two thousand forty-six hips (International Orthopaedics, (2019), 43, 7, (1715-1723), 10.1007/s00264-019-04325-x)

The author name “Muhammad Shawqi” was incorrectly presented as “Muhammad Shawq”

Safety and Efficacy of Evacetrapib in Patients with Inadequately-controlled Hypercholesterolemia and High Cardiovascular Risk; A meta-analysis of Randomized Placebo-controlled Trials

•Evacetrapib could significantly increases the HDL and Apo-A1 levels.•Evacetrapib could significantly decreases the LDL cholesterol and Apo-B levels.•Evacetrapib associated with lower risk of total AEs.•Evacetrapib was not associated with prolonged QT interval.•Evacetrapib was able to gain trust after the off-target side effects of torcetrapib. Low-density lipoprotein cholesterol (LDL-C) is causally related to cardiovascular disease. Inhibition of cholesteryl ester transfer protein with Evacetrapib may provide an additional treatment option for patients who do not reach their LDL-C goal with statins or patients who cannot tolerate statins. We aimed to evaluate the safety and efficacy of Evacetrapib in patients with inadequately-controlled hypercholesterolemia and high cardiovascular risk. A computer literature search for PubMed, Scopus, and Science Direct was carried out from inception to 2019 and was updated from January 2019 till March 2021. We included only RCTs. Data were pooled as a mean difference in a random-effect model using the Mantel-Haenzel (M-H) method. We used Open Meta [Analyst] software (by the center of evidence-based medicine, Oxford University, UK). Five studies (n = 12,937 patients) reported in five articles were included in this meta-analysis. The overall pooled estimate showed that LDL-C was significantly lower in the evacetrapib group than the placebo group (MD -34.07 mg/dL, 95% CI [-40.66, -27.49], p<0.0001). The pooled estimate showed that Apo-B was significantly lower in the evacetrapib130 mg group than the placebo group (MD -22.64 mg/dL, 95% CI [-30.70, -14.58], p<0.0001). HDL-C was significantly higher in the evacetrapib group over the placebo group (MD 93.31 mg/dL, 95% CI [56.07, 130.56], p<0.0001). Current evidence from five RCTs (12,539 participants) suggests that evacetrapib has favorable outcomes in patients with inadequately-controlled Hypercholesterolemia and high cardiovascular risks. Evacetrapib could significantly increase the HDL and Apo-A1 levels and lower the LDL cholesterol and Apo-B levels with an acceptable safety profile