127 research outputs found
Quantification of the Imperfectness of the Molecular Flow Conditions of the Gas Entering the Mass Spectrometer Ion Source for Ionization: Exemplified for CO2 Isotope Amount Ratio Measurements
A new model to describe the gas flow status inside the gas mass spectrometer (MAT 271) inlet system has been developed and applied to the latest isotope amount ratio measurements.JRC.D.4-Isotope measurement
Iodine Doped Graphene for Enhanced Electrocatalytic Oxygen Reduction Reaction in PEM Fuel Cell Applications
Although doped graphene based materials have been intensively investigated, as electrocatalysts for oxygen reduction reaction (ORR), there is still a number of challenges to be explored in order to design a highly active, durable, thermodynamically stable and low-cost catalyst with full recognized technological importance. The application of iodine-doped graphene in fuel cells (FC) has been recently examined as innovative nanomaterial for cathode fabrication. Up to date microscopic and spectroscopic techniques have been combined with structural and electrochemical investigations for a compendious characterization of developed ORR catalysts. The unique structure of doped graphenes is ascertained by the presence of mesopores, vacancies and high surface area, and favors the ions/electrons transportation at nanometric scale. The chapter discusses (a) how to use the existing knowledge in respect to synthesized doped graphenes and (b) how to improve the FC by taking into account these materials and have an enhanced electrochemical performance as well as long-term durability
Determination by Isotope Ratio Mass Spectrometry of the Absolute Isotope Amount Fractions of Oxygen and Nitrogen in Nitrous Oxide
A measurement procedure for the complete isotope characterisation of atmospheric nitrous oxide sample has been developed and applied to establish a first Reference Material for this gas. The whole work has been based on the peculiar instrumental capabilites of "Avogadro" MAT 271IRMS. Additional hardware and software improvement has been done for this mass spectrometer to apply the proposed method.JRC.D.4-Isotope measurement
Steady State Isotopic Transient Kinetic Analysis Study of PEM Fuel Cell Anodes (SPA)
The hydrogen oxidation reaction at Proton Exchange Membrane Fuel Cell anodes is poisoned by part per million levels of carbon monoxide. Pt is the catalyst of choice for the oxidation of pure hydrogen, but it has recently been demonstrated that there is a dynamic equilibrium between CO adsorbed on Pt or Pt/Ru nanoparticles and CO in the gas phase, and that this equilibrium is affected by the competitive adsorption between CO and hydrogen. The purpose of this research is to perform Steady State Isotopic Transient Kinetic Analysis (SSITKA) experiments using the isotopic exchange between 13CO and 12CO to investigate the competitive adsorption of hydrogen and CO on commercial Pt and PtRu catalysts.JRC.D.4-Isotope measurement
Perovskite-Based Materials for Energy Applications
The role of energy in modern society is fundamental. Constraints due to the emissions of air pollutants from the excessive use of fossil fuels have increased dramatically in the last years. Over the years various devices and systems have been developed to transform energy from forms supplied by nature to forms that can be used by people. Another issue is to absorb energy generated at one time and to discharge it to supply power at a later time, what is called energy storage. This is also a matter to focus when it comes to searching for solutions of energy problems. Perovskites are promising key materials for energy applications, and in this chapter is a literature review summarizing the reported progress in energy applications of perovskite-type ceramic materials. To understand the fundamental nature of structure–property relationships, defect chemistry plays an important role. This paper, a mini-review, briefly describes from available literature and summarizes accordingly. It is focused on perovskite crystal structures, perovskite materials for solid oxide fuel cells, perovskite electrocatalyst and photocatalysts, and perovskite transport features
Thyroidectomy without Ligatures in Differentiated Thyroid Cancer
Technical improvements in thyroid surgery are nearly close with the progress of the vessels sealing systems. In all cases, we need to obtain a radical and safe thyroid excision. This chapter is conducted to evaluate the technical key point and the postoperative benefits of our procedure using vessels sealing devices in differentiated thyroid cancers. A prospective study, carried out in First Surgical Clinic, Emergency County Clinical Hospital Tirgu Mureș, Romania from January 01, 2013 to March 01, 2018, based on 100 consecutive patients, divided into two groups: first group without ligatures, using Small Jaw LigaSure™, and the second group operated by conventional procedure. Statistical analysis of some parameters (the thyroid pathology, operative time, hospitalization days, analgesic drugs, immediate postoperative complications and histopathological findings) shows that this procedure provides a total and “complete” removal of the thyroid specimen, with a decreased operative time and fewer hospitalization days
Quality of Life Following Intersphincteric Resections for Low Rectal Cancer: Early Results
Intersphincteric resections are part of the therapeutic arsenal that preserves the sphincterian apparatus. This chapter analyzes the evolution of rectal surgery leading up to intersphincteric resections, deals with anatomical and oncological aspects in rectal cancer, and finally shows our own personal experience with ISR in a series of 40 cases focusing on oncological outcomes, continence, and defecation. As a conclusion, intersphincteric resection represents a feasible therapeutic option in highly selected cases that exempts the patient from the need of a permanent colostomy bag without compromising oncological principles. The Wexner score system is simple and effective in objectifying continence in patients that undergo this type of surgery
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