Search results for "Tripping"
showing 10 items of 66 documents
Thermolytic reverse electrodialysis heat engine: model development, integration and performance analysis
2019
Abstract Salinity gradient heat engines represent an innovative and promising way to convert low-grade heat into electricity by employing salinity gradient technology in a closed-loop configuration. Among the aqueous solutions which can be used as working fluid, ammonium bicarbonate-water solutions appear very promising due to their capability to decompose at low temperature. In this work, an experimentally validated model for a reverse electrodialysis heat engine fed with ammonium bicarbonate-water solutions was developed. The model consists of two validated sub-models purposely integrated, one for the reverse electrodialysis unit and the other for the stripping/absorption regeneration uni…
The Effect of Bark Stripping by Deer (Cervus elaphus L.) on Biometric Parameters of the Scots Pine
2022
Bark stripping by red deer (Cervus elaphus L.) is one of the most acute instances of damage wrought by these animals in a forest. Because of its location, bark stripping causes damage to the thickest and most valuable part of the tree trunk, which lowers the quality of the wood due to technical flaws. The research was conducted in 25 sampling sites of pine stands aged 35 years in a mixed, fresh forest habitat in south-western Poland. The study was aimed at assessing the influence of bark damage by deer on biometric parameters of pine stands (Pinus sylvestris L.). The assessment involved the diameter at breast height, height, basal area and volume of the tree stands. The results revealed a s…
Development of a thermodesorption sensor system for the detection of residual solvents in packaging materials
2004
Application specific sensor systems (formerly electronic noses) use static headspace for the volatile generation from condensed phase samples. This extraction method is very simple to implement, but suffers many drawbacks, i.e. in terms of efficiency or sensitivity to partitioning and is very time-consuming. To circumvent these problems, we developed a new method using dynamic extraction of volatiles (stripping). Although this method is known for GC (gas chromatography), the utilization of direct thermal desorption (DTD) in conjunction with gas sensors is quite novel. The unhandy cold trapping step can be avoided by a software integration of the instantaneous volatile concentration over the…
Characterization of transparent silver loaded poly(l-lactide) films produced by melt-compounding for the sustained release of antimicrobial silver io…
2014
Abstract In the present study, thermally stable silver complexes were produced and incorporated into a poly-( l -lactide) (PLA) matrix by melt-compounding. The effect of the different formulations on the mechanical and color properties was first evaluated. Additionally, the release of silver ions to an aqueous environment was also monitored over time by anodic stripping voltammetry and correlated with the antimicrobial performance against Salmonella enterica. The incorporation of some silver compounds with contents of 1 wt% did not affect the mechanical or optical properties of the films. The films showed a good potential for application in surface treatment and demonstrated a sustainable, …
Anodic stripping voltammetric determination of heavy metals in solutions containing humic acids
1994
Various simultaneous effects of humic acids on the current and potential of differential pulse anodic stripping peaks of copper, lead, cadmium and zinc in weakly alkaline and acidic (pH 2) solutions have been investigated and interpreted with regard to metal complexation and the adsorption of humic acid on the mercury electrode. The applicability of the standard additions method for metal quantitation and the experimental conditions for UV-photolysis with a high-pressure mercury lamp have been examined in model as well as real water samples.
Effect of ethylenediamine on the anodic stripping voltammetric determination of heavy metals in the presence of humic acid
1994
Ligand competition coupled with differential pulse anodic stripping voltammetry has been investigated for the determination of copper, lead and cadmium. Ethylenediamine displaces humic acid in its metal complexes forming kinetically labile compounds. It also eliminates interferences associated with the oxidation of copper. This enhances the sensitivity of the determination of the metals over a wide range of humic acid concentration (up to 30 mg/l). The procedure has been applied to the determination of heavy metals in a real water sample.
Quantitation of Metal Ions in Archaeological Glass by Abrasive Stripping Square-Wave Voltammetry Using Graphite/Polyester Composite Electrodes
2003
A method for identifying Co, Cu, Sb, Sn, Fe, Zn, and Zr pigments in glasses using square-wave voltammetry as the detection mode is described. It is based on the abrasive attachment of glass microsamples to graphite/polyester composite electrodes. Sample amounts less than 1 μg are used allowing for the study of archaeological samples. In all cases well-defined anodic stripping peaks corresponding to the oxidation of metal deposits generated at potentials ranging from −0.6 to −1.6 V (vs. SCE) are obtained. This response is in agreement with that displayed by the corresponding metal oxides. Quantitative estimates of the relative population of metal ions in glasses are obtained from peak area m…
Histologic analysis of specimens from laparoscopic endometrioma excision performed by different surgeons: does the surgeon matter?
2011
Objective To evaluate whether the amount of ovarian tissue inadvertently removed along with the endometrioma cyst wall at laparoscopy differs in relation to the operating surgeon's level of expertise. Design Multicenter, prospective trial. Setting Four tertiary care university hospitals. Patient(s) Fifty patients, aged 25 to 40 years, with monolateral ovarian endometriomas who underwent laparoscopic excision. Intervention(s) Operation with the stripping technique by surgeons with specific expertise in endometriosis surgery in four centers (groups A, B, C, and D) and by residents with average training in laparoscopic surgery (group E). Main Outcome Measure(s) Histologic examination for the e…
Architecture and tectono-stratigraphic evolution of the intramontane Baza Basin (Bétics, SE-Spain): Constraints from seismic imaging
2017
The Baza basin is a large Neogene intramontane basin in the Bétic Cordillera of southern Spain that formed during the Tortonian (late Miocene). The Bétic Cordillera was produced by NW–SE oblique convergence between the Eurasian and African Plates. Three seismic reflection lines (each 18 km long; vibroseis method) were acquired across the Baza basin to reveal the architecture of the sedimentary infill and faulting during basin formation. We applied rather conventional CDP data processing followed by first arrival P-wave tomography to provide complementary structural information and establish velocity models for the post-stack migration. These images show a highly asymmetric structure for the…
Determination of the Boron/Lead Ratio in Ceramic Materials Based on Electrochemical Quartz Crystal Microbalance
2004
A method for quantitatively determining the relationship boron/lead in ceramic materials is presented. It is based on the attachment of microsamples of ceramic frits to an electrochemical quartz crystal microbalance (EQCM). After a reductive deposition step in the � 0.25 to � 0.85 V (vs. AgCl/Ag) potential range, well-defined stripping peaks are recorded in 0.10 M NaCl plus 0.10 M mannitol. The deposition of boron and lead from suspensions of solid materials, and its subsequent oxidative dissolution can be monitorized at the EQCM. The quotient between the maximum mass gain and the corresponding charge passed enables for a direct quantitation of the boron/lead molar ratio in ceramic material…