A new green (chlorine-free) high energy dense oxidizer (HEDO) 2,2,2-trinitroethyl-formate (TNEF) and its propellant formulation based on the hydroxyl-terminated polybutadiene (HTPB) as a binder was prepared and studied. The new oxidizer TNEF was successfully prepared and characterized by nuclear magnetic resonance (NMR) and FTIR spectrometer. Scanning electron microscopy (SEM) was used to check the crystal morphology of the oxidizer. A high specific impulse ( = 250.1 s) was obtained from the characteristics calculation of the new oxidizer instead of ( = 156.9 s) for the commonly used ammonium perchlorate (AP) by using EXPLO5_V6.03 software. The burning behavior and the burning rate were determined by using a high speed camera. TNEF and the propellant formulations were studied by using nonisothermal thermogravimetric analysis (TGA) and the kinetic parameters of the studied samples were determined by using isoconversional (model-free) methods "Kissinger, Ozawa and Flynn-Wall (OFW) and Kissinger-Akahira-Sunose (KAS)". The results proved that the new oxidizer and its formulation based on HTPB have chlorine-free decomposition products and have higher performance characteristics than the traditional propellants.
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http://dx.doi.org/10.1039/c8ra01515e | DOI Listing |
J Eval Clin Pract
February 2025
Centre for Health Care Management, Faculty of Management, University of Warsaw, Warsaw, Poland.
Intro: The article tests the hypothesis that we can draw practical knowledge from the experience of service providers operating in the past. The research questions were formulated: can the historical example of the organization of medical care in the Polish Children's Hospital named after Karol and Maria be used as a viable example today? Is it relevant for contemporary practitioners? And do we still use the knowledge of predecessors? The authors decided to use the interwar Hospital and an operating paediatric ward of the Child-Friendly Hospital for a comparative analysis.
Methods: The model of the European Regional Office of the World Health Organization for integrated delivery of health services was adopted as the analysis framework.
J Eval Clin Pract
February 2025
Department of Obstetrics and Gynecology, Radboud University Medical Center, Nijmegen, The Netherlands.
Rationale: Chronic pelvic pain syndrome (CPPS) is prevalent and a complex multifactorial condition. The incidence is rising. CPPS patients may benefit from multidisciplinary care in a structured care pathway.
View Article and Find Full Text PDFFatigue cracking of rib-to-deck conventional single-sided welded joints is a prevalent issue in orthotropic steel decks (OSDs), significantly impacting their structural integrity and durability. Rib-to-deck innovative double-sided welded joints have the potential to enhance the fatigue resistance of OSD. However, Welding Residual Stresses (WRS) significantly influence the fatigue life of these joints, mandating its consideration in fatigue assessments.
View Article and Find Full Text PDFSci Rep
December 2024
Laboratory of Biochemistry and Vascular Biology, Center for Biologic Evaluation and Research, Food and Drug Administration, Bethesda, 20993, MD, USA.
Blood storage lesion induces cytosolic and membrane changes driven in part by hemoglobin (Hb) oxidation reactions within red blood cells (RBCs). A novel gel formulation containing the antioxidant curcuminoids in a biocompatible solvent system was used to deliver curcumin into RBCs. Incubation of peroxide treated RBCs stored in PBS with curcumin gel led to a reduction in prooxidant ferrylHb and recovery in ATP.
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December 2024
Department of Nano-Chemical Engineering, Faculty of Advanced Technologies, Shiraz University, Shiraz, Iran.
MXene-based (nano)materials have recently emerged as promising solutions for antibiotic photodegradation from aquatic environments, yet they are limited by scalability, stability, and selectivity challenges in practical settings. We formulated FeO-SiO/MXene ternary nano-photocomposites via coupled wet impregnation and sonochemistry approach for optimised tetracycline (TC) removal (the second most used antibiotic worldwide) from water using response surface methodology-central composite design (RSM-CCD). The photocatalysts containing various loading of FeO/SiO (5-45 wt%) on the MXene with a range of calcination temperatures (300-600 °C) via RSM optimisation were synthesised, characterised regarding crystallinity properties, surface morphology, binding energy, and light absorption capability, and analysed for TC degradation efficiency.
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