Capacity Of Capture Research Articles

Overcoming the Problem of Loss-in-Capacity of Calcium Oxide in CO2Capture

Calcium oxide has been identified to be one of the best candidates for CO2 capture in zero-emission power-generation systems. However, it suffers a well-known problem of loss-in-capacity (i.e., its capacity of CO2 capture decreases after it undergoes cycles of carbonation/decarbonation). This problem is a potential obstacle to the adoption of the new technologies. This paper proposes a method of fabricating a CaO-based adsorbent without the problem of loss-in-capacity. An adsorbent was fabricated using the method and tested on a thermogravimetric analyzer. It was shown that the sorbent attained a utilization efficiency of more than 90% after 9 cycles of carbonation/decarbonation.

Polimorphonuclear Cell-Mediated Oxidative Stress: Sink for Reactive Oxygen Species and Cell Various Type Damage

Reactive oxygen species (ROS) are produced in animals and humans under physiologic and pathologic conditions. Polymorphonuclear cells (PMNs) and other professional phagocytes are able to generate large amounts of ROS that have not only antimicrobial capacity but are also deleterious to mammalian cells and responsible for many chronic diseases.In particular, ROS produced in large amounts by the massively infiltrating leukocytes in inflammed tissues are believed to constitute a major tissue-destructive force and may contribute significantly to the pathogenesis of several inflammatory diseases.Inflammation can accelerate the development of cancer: in fact, it seems that a part of the predisposition to cancer may be attributed to the oxidants released by the phagocytes at inflammatory site and then to the effects of continuous damage over a life span by ROS. The focus of this study was to investigate the differential capacity of ROS capture and the relative cellular damage degree in gastric, intestinal and fibroblastic cell lines. These various cell types were in vitro used as sink for ROS released by co-cultured fMLP-stimulated human polymorphonuclear cells.Our data demonstrated that cell lines showed a differential capacity of ROS capture correlated to cellular damage, probably due to a different cell susceptibilty to the oxidative challenge produced by stimulated PMNs.

Thermoluminescence of ZnS

Abstract A number of zinc sulphide phosphors containing cobalt was prepared with various concentrations of additional impurities. Co++-ions in both copper and silver activated phosphors produce a characteristic glowcurve, showing three distinct peaks above liquid nitrogen temperature. It was established that the first and probably the second glowpeak is connected with distinct traps, while the third peak is caused by a continuous distribution of traps. Measurements of thermoluminescence spectra as well as investigations of energy storage capacity and temperature dependence of electron capture in traps pointed to a local association of traps and luminescence centres in the case of the first two glowpeaks, whereas electron transfer via the conduction band from traps to separated luminescence centers was assumed for the third peak. An already existing model was used for discussing the experimental results obtained.