Fly ash, a byproduct of coal burning and gasification, is significant source global pollution classified as hazardous waste. However, physicochemical treatments can improve their adsorption capacity by increasing surface area. This research aimed to enhance the fly ash from brick manufacturing industry remove Cd(II) ions optimizing its The treatment process was designed with two factors: sodium hydroxide concentration stirring time, each evaluated at three levels. modification confirmed...

Atmospheric pollution results from toxic gases in low concentrations, originating natural processes and human activities. These interact with each other the presence of solar radiation, forming much more complex compounds that contribute to formation photochemical smog. This study presents a mathematical model estimate daily concentrations primary secondary pollutants, assuming spatial variation is not considered within control volume. The includes nitrogen oxides, ozone, hydrocarbons,...

ZnO nanoparticles (ZnO-NP) present innovative optical, electrical, and magnetic properties that depend on specific characteristics, e.g., size, distribution, morphology. Thus, these are essential to address various applications in areas such as electronics, medicine, energy, others. In addition, the performance of this ZnONP depends their preparation which can be done by chemical, physical, biological methods. Meanwhile, nowadays, main interest developing ZnO-NP synthesis through methods...

The modeling and simulation of the catalytic dehydrogenation process cyclohexanol in a fixed-bed reactor is presented, leading to finding relationship between effectiveness factor, Thiele modulus, Weisz–Prater modulus catalyst particles with respect their axial radial position, for which external conditions concentration temperature around each particle were previously obtained by applying material energy balances bed considering two-dimensional pseudo-homogeneous model diffusion....

The influence of near surface structure termination and treatments on the electric fields mobility modulation doped AlGaAs/GaAs heterostructures (MDH) were investigated. built-in evaluated by photoreflectance spectroscopy, these values utilized to simulate conduction band bending MDH. When capping layer MDH was changed, both built in internal field are decreased, while electron samples is increased. After passivated with Si, also reduced. Finally, a (NH4)2Sx-based treatment applied,...

ZnO nanoparticles (ZnO-NP) present innovative optical, electrical, and magnetic properties that depend on specific characteristics, e.g., size, distribution, morphology. Thus, these are essential to address various applications in areas such as electronics, medicine, energy, others. In addition, the performance of this ZnONP depends their preparation which can be done by chemical, physical, biological methods. Meanwhile, nowadays, main interest developing ZnO-NP synthesis through methods...

A simple wireless charger circuit for mobile phones is presented. The aim of the study to implement charging on devices not equipped it. driver based a half bridge inverter and series-series resonant converter. Experimental results validates analysis design shows feasibility proposal.

We report on photoreflectance anisotropy (PRA) spectroscopy of InGaAs/AlAs/AlAsSb coupled double quantum wells (CDQWs) with extremely thin coupling AlAs barriers grown by molecular beam epitaxy (MBE), no intentional doping. By probing the in-plane interfacial optical anisotropies (OAs), it is shown that PRA has ability to detect and distinguish semiconductor layers dimensions, as anisotropic (PR) signal stems entirely from buried (QWs). In order account for experimental spectra, a...

The rheological behavior of aqueous solutions polyvinyl alcohol at 4, 6, 8 and 10% by weight has been studied evaluated temperatures 20, 25, 30 35 °C, using five non-Newtonian fluid models independent time: Ferrys, Robertson-Stiff, Williamson, Sisko, Ellis de Haven. classical method consists in carrying out regression analysis. Using a comparative procedure determination coefficients variances, the model that most appropriately adjusts experimental data to said is selected. From statistical...

The objective of this research is to find the effectiveness factor catalyst particles for most favorable conditions phthalic anhydride production in a fixed bed reactor, with aim achieving highest rate compared other secondary products and analyzing areas lower modification reactor design. Initially, material energy balances catalytic are solved obtain concentration temperature profiles based on radius length using polymath software(Polymath® v6.2 Software Minitab 19 Matlab 2019) data from...

The aim of this study was to assess the influence hydrogel and zinc oxide nanoparticles on quinoa germination establishment. Various doses a commercial potassium-based (0, 5, 7, 9 g), each dissolved in one liter rainwater, were applied. Additionally, 1.5 g (ZnO-NP) pre-crushed nitrogen fertilizer, at rate 1.6 kg/ha, added solution achieve homogeneous mixture. Following application 10-linear-meter rows corresponding treatment area every block, 25 seeds per linear meter "Blanca de Juli"...

The field of plasmonics, an optics discipline that studies the interaction light with matter for structures dimensions similar to wavelength electromagnetic radiation affecting them, has been further developed support computational technologies are capable performing calculations large volumes data solve complex problems this discipline. Some in plasmonics require use algorithmic techniques can simultaneously handle more than one function tend not present their maximum or minimum at same...

In this work, the bolometric parameters of Sierpinski fractal antenna-coupled SWCNT semi-metallic films are obtained by thermoelectric characterization, in order to find out performance as bolometer. The method was based on an experimental setup considering a line-of-sight wireless link between two identical planar antennas, infrared thermography, and electrical resistance measurements. considered antennas resonant frequencies. Both transmitting receiving antenna were third-iteration dipoles...

Several hydrogels were synthesized by free-radical polymerization in an aqueous medium based on potato starch (PS), poly(vinyl alcohol) (PVA), and N,N′-Methylenebisacrylamide (MBAm), being possible to study these as a function of the proportion components incorporated. In this way, products generated from synthesis characterized swelling deswelling kinetics, first verified with Schott statistical models, allowing contrast proximity between experimental theoretical behavior. Additionally,...

Derivation and application of

Objetivo. Dimensionar y caracterizar la pobreza energética en población indígena del Estado de San Luis Potosí, México. Metodología. Se diseñó, validó aplicó, mediante muestreo estadístico aleatorio, un instrumento tipo cuestionario los cinco municipios indígenas con mayores tasas marginación. Los datos recolectados fueron capturados analizados estadísticamente. Resultados. La vertiente más grave está el acceso a combustibles no contaminantes, dado que uso leña hogares alcanza 93.2 %,...

We have used photoreflectance-anisotropy (PRA) spectroscopy as an optical probe for the characterization of heterostructure lasers with active region consisting InAs quantum dots (QDs) embedded in a series three stacked In <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.15</inf> Ga xmlns:xlink="http://www.w3.org/1999/xlink">0.85</inf> As wells (QWs). By probing in-plane anisotropy, we demonstrate that PRA has ability to detect and...

En este trabajo se reporta la fabricación de un dispositivo láser semiconductores III-V confinamiento separado. La heteroestructura creció usando técnica epitaxia por haces moleculares y caracterizó óptica, topográfica eléctricamente medio fotoluminiscencia, microscopia tunelamiento, electroluminiscencia, relaciones corriente-voltaje corriente-potencia, respectivamente. El electrónico es llevado a cabo emparedamiento del área activa con pozos cuánticos InGaAs una composición que permite...

We report the visualization of interface optical anisotropies in III-V semiconductor based coupled double quantum wells by using photoreflectance anisotropy spectroscopy. Interfacial were detected from buried layers with dimensions at room temperature through a piezoelectric shear strain. The discrete transitions associated to observed near-infrared range, specifically second telecommunication band. propose use this extended spectroscopy polarization contrast as simple and complementary...

En este trabajo se reporta la fabricación de un dispositivo recortador onda basado en LabVIEW. El consiste usar pulsos ópticos infrarrojos para controlar velocidad una hélice con motor corriente continua operado a 6 V. Con punto prueba estimado 1000 rpm, hace girar 12 aperturas frecuencia giro exacta por medio sistema retroalimentado configuración control PID, esta manera obtenemos que tienen forma y particular controlada. Por tarjeta bajo costo NIDAQ-USB6002, LabVIEW utilizan las...

En este trabajo se presentan estudios de composición química y control crecimiento pozos cuánticos semiconductores basados en III-V (AlGaAs/GaAs/AlGaAs, utilizando una del Al 33 %) fabricados un sistema epitaxia por haces moleculares. Se utilizó la técnica difracción electrones reflejados alta energía (in-situ) para caracterización química, así como espectroscopía fotoluminiscencia (ex-situ) a baja temperatura el análisis los niveles tres diferentes no-acoplados. obtuvo buena...

Se presenta el estudio de nanoantenas geometría estelar como elementos plasmónicos amplificadores y direccionales del campo electromagnético. El se llevó a cabo con análisis numérico basado en la técnica elemento finito. Fueron analizados varios materiales, dimensiones arreglos geométricos frecuencias para simulación datos. La fue elegida base propiedad autoensamblado los materiales plata-óxido zinc (Ag-ZnO). direccionalidad amplificación eléctrico fueron simulados tanto cercano...

Phosphorus (P) is one of the most limiting nutrients for plant species and its intensive use can exhaust world reserves. In general, forest production unviable without availability P. The objective study was to determine effect phosphate fertilization on growth four families lemon eucalyptus (Corymbia citriodora). Plants produced from seeds seed trees were used, which subjected seven doses phosphorus: 0, 25, 50, 75, 100, 125 150 mg P dm-3. experiment carried out in a 7 × 4 factorial...