13 research outputs found
Data for: Technology, Ecology and Agricultural Trade
No full textPrograms and data files associated with "Technology, Ecology and Agricultural Trade." Author: Kari E.R. Heerman
The potentiostatic transient, for 3D nucleation with diffusion-controlled growth: theory and experiment for progressive nucleation
No full textThe theory of the potentiostatic transient for 3D nucleation with diffusion-controlled growth is discussed. It is shown that the theoretical model of Mirkin and Nilov [J. Electroanal. Chem., 283 (1990) 35] and Heerman and Tarallo [J. Electroanal. Chem., 470 (1999) 70] predicts too high values of the current, which becomes very apparent for high values of the site density and low values of the nucleation rate constant (progressive nucleation). For example, the model then predicts that the current in the limit of long times will be higher than the Cottrell limit by a factor of 4/3 which is physically unacceptable. Therefore, a modification to this model is proposed which is based on a careful analysis of the Kolmogorov-Avrami theorem. The "extended area" in the Kolmogorov-Avrami theorem includes contributions from "phantom nuclei" that are born inside already existing zones but do not exist physically. This is necessary to preserve the randomness of the system and allows the correct calculation of the appearance rate of the nuclei and the nucleus saturation density. The "extended current", defined in analogy with the "extended area", then also attributes current to the phantom nuclei. It follows that the ratio j(ex)(t)/theta(ex)(t) which appears in the model of Mirkin and Nilov and Heerman and Tarallo does not correspond to the actual number of nuclei formed on the electrode. Therefore, the "extended quantities" in this ratio must be replaced with quantities that relate directly to the real number of clusters (this implies what is fairly obvious, that the appearance rate of the clusters must be calculated first). This makes it is possible to derive an equation that predicts correctly the current in the limits of both short and long times which is directly linked to the N-a(t) vs. time relation (where N-a(t) is the actual number of nuclei on the electrode). Experiments for the nucleation of silver on glassy carbon electrodes, with the simultaneous recording of both j(t) vs. time and N-a(t) vs. time relations, are described. The experimental results obtained from the transients and the direct visual counting of nuclei are compared with the theoretical predictions. (C) 2004 Elsevier B.V. All rights reserved.status: Publishe
AFM Study of the Incorporation of Particles in Metals During Electrodeposition
No full textstatus: Publishe
Electrochemical nucleation with diffusion-limited growth. Properties and analysis of transients
No full textTheory of the chronoamperometric transient for electrochemical nucleation with diffusion-controlled growth
No full textElectrochemical nucleation on microelectrodes. Theory and experiment for diffusion-controlled growth
No full textData for: Technology, Ecology and Agricultural Trade
No full textPrograms and data files associated with "Technology, Ecology and Agricultural Trade." Author: Kari E.R. Heerman.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV
Optical absorption study of Rh(III)- and Ir(III)-doped NaCl single crystals (NaCl:M3+, MRh3+, Ir3+)—A crystal field analysis
No full textA guide to measuring heart and respiratory rates based on off-the-shelf photoplethysmographic hardware and open-source software
No full textThe remote monitoring of vital signs via wearable devices holds significant potential for alleviating the strain on hospital resources and elder-care facilities. Among the various techniques available, photoplethysmography stands out as particularly promising for assessing vital signs such as heart rate, respiratory rate, oxygen saturation, and blood pressure. Despite the efficacy of this method, many commercially available wearables, bearing Conformit & eacute; Europ & eacute;enne marks and the approval of the Food and Drug Administration, are often integrated within proprietary, closed data ecosystems and are very expensive. In an effort to democratize access to affordable wearable devices, our research endeavored to develop an open-source photoplethysmographic sensor utilizing off-the-shelf hardware and open-source software components. The primary aim of this investigation was to ascertain whether the combination of off-the-shelf hardware components and open-source software yielded vital-sign measurements (specifically heart rate and respiratory rate) comparable to those obtained from more expensive, commercially endorsed medical devices. Conducted as a prospective, single-center study, the research involved the assessment of fifteen participants for three minutes in four distinct positions, supine, seated, standing, and walking in place. The sensor consisted of four PulseSensors measuring photoplethysmographic signals with green light in reflection mode. Subsequent signal processing utilized various open-source Python packages. The heart rate assessment involved the comparison of three distinct methodologies, while the respiratory rate analysis entailed the evaluation of fifteen different algorithmic combinations. For one-minute average heart rates' determination, the Neurokit process pipeline achieved the best results in a seated position with a Spearman's coefficient of 0.9 and a mean difference of 0.59 BPM. For the respiratory rate, the combined utilization of Neurokit and Charlton algorithms yielded the most favorable outcomes with a Spearman's coefficient of 0.82 and a mean difference of 1.90 BrPM. This research found that off-the-shelf components are able to produce comparable results for heart and respiratory rates to those of commercial and approved medical wearables
Proceedings of the National Conference on Managing Irrigation for Environmentally Sustainable Agriculture in Pakistan, Islamabad, November 5-7, 1996. Volume III - Papers on the theme, Water management below the Mogha
No full textWater allocationWater distributionWatercoursesIrrigation waterIrrigation canalsWaterloggingSalinityWater useDecision makingSurface drainageIrrigation designIrrigation requirementsSprinkler irrigationWheatSurface irrigationIrrigation schedulingCottonCrop yieldSoil reclamationSodic soilsSoil salinityConjunctive useGroundwaterSurface waterFlow measurementIrrigation practicesMonitoringEvaluationFarmer participationFarmers' attitudes
