Ciencias Exactas y Ciencias de la Salud
Permanent URI for this collectionhttps://hdl.handle.net/11285/551039
Pertenecen a esta colección Tesis y Trabajos de grado de las Maestrías correspondientes a las Escuelas de Ingeniería y Ciencias así como a Medicina y Ciencias de la Salud.
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- New Generation of 3D printed electrospray sources for microencapsulation in biomedical applications(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2018-05-14) Benjamin de Jesus, Benjamín Evani; Zúñiga, Alex Elías; Olivera Trejo, Daniel; Martínez Romero, Oscar; García López, ErikaAdditive manufacturing by Digital Light Processor stereolithography (DLP-SLA) has shown a great potential to create high-density microfluidic devices due to it offers high resolution and relatively low-cost. In this work, the fabrication of 3D printed coaxial electrospray sources with a high density of emitters are reported by using DLP-SLA technology. The 3D printed electrospray sources have also proven to work correctly as a source of microencapsulation. To accomplish the objectives of the study, it was addressed in three sections primarily. First, the influence of the involved parameters on the final properties of printed microchannels was evaluated by the analysis and characterization of this promising additive manufacturing technology. Second, based on its maximum printing capabilities, multiplexed electrospray sources were designed. To manufacture suitable channels with diameters up to 160 µm, it was key to establish the smallest dimensions of the new devices, which were successfully printed with 41 and 57 coaxial emitters respectively. Finally, Vitamin D and alginate hydrogel were used to produce core-shell microparticles as an initial exploration in the encapsulation of biomedical substances via coaxial electrospraying. The accurate encapsulation was dependent on the flow rate, applied voltages, and mainly on the concentration of alginate solution.
- Design, simulation and application of a PCL membrane with TiO2 and Ag nanoparticles for a novel geometry fog water harvesting device(Instituto Tecnológico y de Estudios Superiores de Monterrey) Borbolla Torres, César Iván; Zúñiga, Alex Elías; Martínez Romero, Oscar; School of Engineering and Sciences; School of Engineering and Sciences; Campus Monterrey; Del Ángel Sánchez, KarinaNowadays, the world faces an increasing water crisis problem that will become even more severe in the years to come. Fog-water harvesting represents an economical and efficient alternative to address water scarcity around the world. In this study a report on the development of Polycaprolactone (PCL) composite membranes using TiO2 nanoparticles (NPs), Ag NPs and Ag-TiO2 NPs is presented, besides the effect of using two different solvents, acetic acid and a mixture of chloroform and N,N-dimethylformamide (DMF), to achieve a hydrophobic material capable of assisting fog-water harvesting applications. The proposal of a novel geometry is presented validated through mechanical and air-flow simulation. Beside the investigation and development of a new manufacture procedure for the application of the composite polymer material on a commercial Rashel mesh to enhance its properties. Surface morphology and roughness were explored by scanning electron and infinity focus microscopy, a more homogeneous morphology was observed for composites elaborated with chloroform-DMF. The degree of crystallinity and structural properties were investigated by differential scanning calorimetry and x-ray diffraction. The interaction between PCL and the dopants NPs was studied by Fourier transform infrared spectroscopy, detecting a shift to lower wavenumbers in the principal polymer modes corroborating a compatibility between the solvents, the NPs and the PCL polymer matrix. The permeability of the membranes was analyzed by water contact angle and the mechanical performance was investigated by using a uniaxial quasi-static test and equibiaxial cyclic test. The results obtained show an improvement in such properties for the composites elaborated with chloroform-DMF. Air-flow simulation shows a smoother flux and focused condensation on the pores´ edges. Finite element analysis showed an increase on the mechanical stability of the mesh when the geometry is changed. The geometry proposed enhances water collection against planar profiles. Values obtained in the fog-water collection efficiency tests demonstrate the feasibility and the potential of the composite material developed whit the highest value of 5 l/m2/hr. achieved. This research is relevant to set the experimental parameters and the application procedure to manufacture a high collection efficiency fog-water harvesting device based on a PCL.