17 research outputs found
Novel supercapacitor electrodes based semiconductor nanoheterostructure of CdS/rGO/CeO2 as efficient candidates
In this study, we have synthesized metal oxide/metal sulphide based nanoheterostuctures mediated with graphene nanosheets. The synthesized nanoheterostructures were characterized via different techniques such as XRD, XPS, and TEM. The electrochemical characteristics of the investigated nanoheterostucture (CdS/rGO/CeO2) were investigated through electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and galvanostatic charge-discharge. The specific capacitance of the single rGO, binary CdS/CeO2 and ternary CdS/rGO/CeO2 heterostructures were measured. The CdS/rGO/CeO2 nanoheterostucture showed the most excellent cycling stability with high specific capacitance of 407 F g−1 achieved at a charge-discharge rate of 1 A/g. The investigated supercapacitor retained about 96% of the initial energy density after charge-discharge at a 10 A/g for 5000 cycles. The ternary CdS/rGO/CeO2 nanoheterostucture revealed the best specific capacitance as the graphene nanosheets increased interfacial electron transfer. The results revealed that the investigated novel nanoheterostucture is among the best reported ones in the literature. Keywords: Nanoheterostucture, Semiconductors, Galvanostatic charge-discharge, Specific capacitanc
Corrosion inhibition of carbon steel by Roselle extract in hydrochloric acid solution: electrochemical and surface study
Tissue factor pathway inhibitor, natural coagulation inhibitors and hemostatic activation markets in patients with acute coronary syndromes
Departments of Cardiology (Al-Nozha, Arafah, Al-Harthi), Physiology (Abdel-Gader), Endocrinology (Al-Maatouq), College of Medicine,
King Khalid University HospitalThis study aims at characterizing the
hemostatic changes, in a large cohort of Saudi Arab
patients with acute coronary syndromes.
Methods: We consecutively enrolled 389 patients
(unstable angina [UA]: n=181; myocardial infarction
[MI]: n=208) in this study at King Khalid University
Hospital, Riyadh, Kingdom of Saudi Arabia in the period
from April 2000 to November 2001. We collected blood
samples before coronary angiography. Controls (n=101)
were healthy males and females. All hemostatic assays
were undertaken using enzyme linked immunosorbent
assay based techniques and commercial kits.
Results: The mean plasma levels of both bound and
free tissue factor pathway inhibitors (TFPI) were
significantly higher and to comparable levels, in patients
with MI and UA, than in healthy control levels. Markers
of thrombin generation: the mean levels of prothrombin
fraction 1+2, thrombin antithrombin complexes, and
D-Dimer were very significantly elevated in the 2
patients groups than in controls. Proteins C and
antithrombin III showed statistically significant reduction
especially in patients with MI. Plasminogen activator
inhibitor levels were significantly elevated in the 2
patient groups, but were higher in MI patients. The mean
levels of fibrinogen and D-Dimer as well thrombin
antithrombin complex were higher and the levels of free
tissue factor pathway inhibitor were lower in patients
with 3-vessel coronary artery disease than those with
single and double vessel disease.
Conclusion: The results of this study confirm the
existence, and to a similar extent, of a hypercoagulable state in Saudi patients with MI than UA and in those with 3-vessel coronary artery disease than those with one or 2-vessel disease