Motivation of achievement and problem solving with linear functions at a university in Surco

The objective of this research study was to determine the relationship between the motivation of achievement and the resolution of problems with linear functions of the students of Foundations of Calculus for the afternoon course of the Faculty of Business at the Peruvian University of Applied Sciences, 2017. This study was developed within a quantitative approach, with a hypothetical deductive method and non-experimental design. The sample consisted of 76 students of Foundations of Calculus from the Faculty of Business of the aforementioned university. The results show that there is no direct and significant relationship between the motivation of achievement and the resolution of problems with linear functions of the students surveyed. This further showed that the competency to solve problems does not depend on motivation, but rather requires knowledge and skills that are put into practice.La presente investigación tuvo como objetivo determinar la relación entre la motivación del logro y la resolución de problemas con funciones lineales de los estudiantes de Fundamentos para el Cálculo del turno tarde de la Facultad de Negocios en la Universidad Peruana de Ciencias Aplicadas, 2017. Este estudio se desarrolló dentro de un enfoque cuantitativo, con un método hipotético deductivo y diseño no experimental. La muestra estuvo conformada por 76 estudiantes de Fundamentos para el Cálculo de la Facultad de Negocios de la universidad mencionada. Los resultados permitieron determinar que no existe relación directa y significativa entre la motivación del logro y la resolución de problemas con funciones lineales de los estudiantes encuestados. Esto demostró que la competencia de resolver problemas no depende de la motivación, sino más bien se requiere de conocimiento y habilidades que se manejen

Material parameters in thick hydrogenated amorphous silicon radiation detectors

Transient photoconductivity measurements of basic material parameters: carrier mobility, mobility-lifetime product and the ionized dangling bind density of thick hydrogenated amorphous silicon detectors are presented. We found that only a fraction ({approximately}30--35%) of the total defect density as measured by ESR is ionized when the detector is biased into deep depletion. The measurements on annealed samples done to relate the ionized dangling bond density and the ESR spin density also showed that this fraction is about 0.3. The time dependence of defect relaxation was found to be a stretched exponential. 5 refs., 3 figs., 1 tab

Improved charge collection of the buried p-i-n a-Si:H radiation detectors

Charge collection in hydrogenated amorphous silicon (a-Si:H) radiation detectors is improved for high LET particle detection by adding thin intrinsic layers to the usual p-i-n structure. This buried p-i-n structure enables us to apply higher bias and the electric field is enhanced. When irradiated by 5.8 MeV {alpha} particles, the 5.7 {mu}m thick buried p-i-n detector with bias 300V gives a signal size of 60,000 electrons, compared to about 20,000 electrons with the simple p-i-n detectors. The improved charge collection in the new structure is discussed. The capability of tailoring the field profile by doping a-Si:H opens a way to some interesting device structures. 17 refs., 7 figs

Measurements of 1/f noise in A-Si:H pin diodes and thin-film-transistors

We measured the equivalent noise charge of a-Si:H pin diodes (5 {approximately} 45{mu}m i-layer) with a pulse shaping time of 2.5 {mu}sec under reverse biases up to 30 V/{mu}m and analyzed it as a four component noise source. The frequency spectra of 1/f noise on the soft-breakdown region and of the Nyquist noise from contact resistance of diodes were measured. Using the conversion equations for a CR-RC shaper, we identified the contact resistance noise and the 1/f noise as the main noise sources in the low bias and high bias regions respectively. The 1/f noise of a-Si:H TFTs with channel length of 15 {mu}m was measured to be the dominant component up to {approximately}100kHz for both saturation and linear regions. 15 refs., 7 figs

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

Potential for the use of pyrolytic tar from bagasse in industry

Tar From pyrolyzed bagasse was characterized according to its main structural features. Its solubility in NaOH solutions results in an alkaline tar solution (ATS) that exhibits surface active properties. The prepared ATS was successfully used as a foam flotation agent in copper mining, as a foaming agent in foam concrete formation, and as a fluidization agent for Portland cement manufacture. The potentialities of by-products of conventional pyrolysis and carbonization processed are stressed. (C) 1997 Elsevier Science Ltd.12536336

Unidimensional heat transfer analysis of elephant grass and sugar cane bagasse slow pyrolysis in a fixed bed reactor

Elephant grass (Pennicetum purpureum) and sugar cane bagasse slow pyrolysis experiments was carried out in a fixed bed reactor. A 20-cm internal diameter and 12-cm-long reactor was used. Particulate biomass filled up the reactor volume. Biomass was loaded into the reactor and heated in the axial direction using an electrical resistance located at the reactor's bottom. In order to control the temperature variation during the biomass pyrolysis process, four thermocouples were installed inside of the reactor. The remain residual mass was constant approximately after 73 min of heating; the running was stopped and remain carbonised; material was manually removed from the reactor. The residue formed three layer of biomass visually different described in detail here. Proximate analysis and higher heating value (HHV) tests were carried out to the material in each layer. Mass loss against time was recorded during experiments. The results indicated that the carbonisation ratio decreases in time because the carbon layer has low thermal conductivity and it does not permit proper heat transfer to the upper layer of biomass. It means that technology that avoids high-temperature gradients during the pyrolysis of bulk-dispersed biomass could avoid the problems described before. (C) 2004 Elsevier B.V. All rights reserved.86556557

Energy sector in Ecuador: Current status

This paper describes the current energy sector in Ecuador, its present structure, the oil industry, Subsidies, and renewable energy, focusing on the evolution and reform of the electricity sector. Currently, 86% of the primary energy originates from nonrenewable sources. In 2005, the gross electricity generation was 15127 GWh (45.5% hydropower, 43.11% thermal, and 11.39% imported). Ecuador is the fifth largest oil producer in South America but lacks sufficient oil refining capacity. Reserves of natural gas (NG) are small, and most of NG is produced from oil fields without energy recovery. Several projects are underway to increase the utilization of NG and renewable energies to meet Ecuador commitments to the Kyoto Protocol. (c) 2007 Elsevier Ltd. All rights reserved.3584177418

A statistical analysis of the auto thermal fast pyrolysis of elephant grass in fluidized bed reactor based on produced charcoal

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)This research presents and discusses the results of product yields, higher heating value, proximate and ultimate analyses of the charcoal obtained in the Fast Pyrolysis Plant PPR-200. It is a fast pyrolysis plant with a biomass feed capacity of 200 kg per hour, owned by Unicamp. Elephant grass with an average particle diameter of 2 mm and 12% of moisture was used as raw material. The PPR-200 facility operated under different conditions. Air was used as fluidization agent. This study tries to increase the knowledge of the PPR-200 plant operation in fast pyrolysis regimen. Experimental tests were carried out considering two independent factors: fluidization air and stoichiometric air ratio and the height of the fixed bed. In the pyrolysis process, a charcoal with a high carbon content is obtained as well as the release of oxygen from the biomass. Experimental results showed that the favorable operating conditions for oxygen release from elephant grass and carbon concentration in the charcoal are a fixed fluidized bed of 207 mm height and 8% of supplied air to the stoichiometric air ratio. Under these optimized conditions, the fluidized bed temperature resulted to be 650 degrees C on average and the yield production of charcoal in relation to the biomass fed (dry and ash free, d.a.f.) was of 14 wt.%. The charcoal produced under such conditions presented 92.4% of elemental carbon, and 2.85% of elemental oxygen. (C) 2014 Elsevier Ltd. All rights reserved.6541671322329Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)MME (Brazilian Ministry of Mines and Energy)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq