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Los nanotubos de carbono pueden ser sintetizados utilizando diversas técnicas. Este trabajo tiene como objetivo estudiar el proceso experimental de crecimiento de nanotubos de carbono mediante deposición química en fase vapor asistida por plasma (PECVD, por sus siglas en inglés). Además, el estudio pretende calibrar el reactor y desarrollar un código en LabVIEW para introducir agua en el proceso, permitiendo así un procedimiento PECVD asistido por agua. Las muestras obtenidas son evaluadas a través del análisis de imágenes SEM y espectros Raman., Carbon nanotubes can be synthesized using various techniques. This work aims to study the experimental process of growing carbon nanotubes via plasma-enhanced chemical vapor deposition (PECVD). Additionally, the study aims to calibrate the reactor and develop a LabVIEW code to introduce water into the process, enabling a water-assisted PECVD procedure. The obtained samples are evaluated through the analysis of SEM images and Raman spectra.

The overexpression of folate receptors on cell surfaces is associated with abnormalities linked to epithelial cancers. This study reports on a capacitive biosensor that employs folic acid as a recognition molecule for the biosensing of folate receptors. The biosensor is composed of a thin film of Ti–W oxides conjugated with folic acid that serves as a working electrode in a three-electrode electrochemical cell configuration. The thin film of Ti–W oxides, featuring a mixture of TiO2 anatase and rutile phases, was fabricated using the pulsed laser deposition method and subsequently functionalized with folic acid. Characterization of the thin film before and after functionalization was conducted using AFM, XPS, and contact angle measurements. The functionalization study confirmed a stable bond between folic acid and the surface of the thin film. The interaction between the functionalized transducer and the folate receptor was investigated by determining the electrochemical capacitance using an electrochemical capacitance spectroscopy setup. Folate receptor recognition assays demonstrated that the biosensor response signal, or chemical hardness (in terms of electrochemical capacitance), is selective and directly proportional to the folate receptor concentration, with a limit of detection of 200 pM (0.2 nM). These findings are promising for the application of this detector in the recognition of folate receptors, particularly for point-of-care analysis.

TiO2 thin-films functionalized with specific biomolecules have been used in the fabrication of highly sensitive and selective electrochemical biosensors focused on detecting a variety of diseases. Among the biosensors of scientific and technological interest are those obtained from the functionalization of nanomaterials with folic acid to recognize folate receptors; their importance lies in the fact that these receptors are overexpressed in most abnormal cells, and their identification can allow the detection of tumor cells and the photothermal treatment of cancer. This work presents a methodology for fabricating TiO2 thin-films and functionalizing them with folic acid. X-ray photoelectron spectroscopy, atomic force microscopy, Raman spectroscopy, and contact angle measurements were used to examine the adsorption of folic acid on TiO2 thin-film surfaces grown by pulsed laser deposition. XPS and Raman analysis indicated that the interaction of folic acid with the TiO2 surface occurred either through the pteridine ring or through the carboxylic groups of the glutamic acid portion

In this document we will study and solve the nonlinear partial differential equation, with initial conditions for vehicle entry that serves to model the dynamics of traffic flow. To find a numerical solution to the dynamics that govern the behavior of traffic flow, the Finite Element Method in a spatial dimension was used. In accordance with the temporal dynamics, simulations were developed to know the flow in terms of time. The numerical solution is interesting for predicting the number of vehicles at the entrance to a high-flow road. Some theorems are enunciated that guarantee the existence of the solution and the uniqueness is given by the boundary conditions., En este documento estudiaremos y resolveremos la ecuación diferencial parcial no lineal, con condiciones iniciales de entrada de vehículos que sirve para modelar la dinámica del flujo de tráfico. Para encontrar una solución numérica de la dinámica que gobierna el comportamiento del flujo de tráfico, se usó el Método de Elementos Finitos en una dimensión espacial. De acuerdo con la dinámica temporal se desarrollaron simulaciones para conocer el flujo en términos del tiempo. La solución numérica resulta interesante para la predicción de la cantidad de vehículos a la entrada de una vía de alto flujo. Se enuncian algunos teoremas que garantizan la existencia de la solución y la unicidad viene dada por las condiciones de contorno.

Traditional data processing applications are unsuitable for handling large amounts of data. To achieve an efficient manipulation and extraction of characteristics or samples that the information represents, it is necessary to know aspects such as data collection and treatment. In this document, a database corresponding to the behavior of electrical energy consumption in a residential load was refined. The debugging and statistical analysis of the samples were carried out using the principal component analysis. The training of the smallest data set to the original database was made using vector support machine techniques and artificial neural networks. Finally, a proposal is presented for the analysis of samples that are within the operating limits or not using updating dynamic patterns for the unsupervised validation of new samples., Las aplicaciones de procesamiento de datos tradicionales son inadecuadas para el manejo de una cantidad elevada de datos. Para lograr una eficiente manipulación y extracción de características o muestras que representa la información, es necesario conocer aspectos como la captación y tratamiento de datos. En este documento se depuró una base de datos correspondiente al comportamiento del consumo de energía eléctrica en una carga residencial. La depuración y análisis estadístico de las muestras se realizó por medio del análisis de componentes principales. El entrenamiento del conjunto de datos de menor dimensión a la base de datos original se hizo por medio de las técnicas de máquina de soporte vectorial y redes neuronales artificiales. Finalmente, se presenta una propuesta de análisis de muestras que se encuentren o no dentro de los límites de operación por medio de la actualización de patrones dinámicos para la validación no supervisada de nuevas muestras.

Gamma-alumina (gamma-Al2O3) powder was characterized by hard x-ray photoelectron spectroscopy with an Ag L-alpha (2984.2 eV) excitation source. The sample was fixed to a stainless-steel sample holder with copper double-sided adhesive tape. Survey spectrum, C 1s, O 1s, Al 1s, Al KLL, Al 2s, and Al 2p core levels spectra were acquired., Prášek gama-aluminy (gama-Al2O3) byl charakterizován pomocí rentgenové foto-elektronové spektroskopie s využitím Ag L-alfa (2984.2 eV) excitačního zdroje. Vzorek byl připevněn k nerezovému držáku vzorků pomocí oboustranné měděné pásky. V rámci měření bylo pořízeno survey spektrum a core level spektra C 1s, O 1s, Al 1s, Al KLL, Al 2s, a Al 2p.