Publications by authors named "Francisco Lopez-Huerta"

Acetaldehyde is a volatile organic compound that can cause damage at the cellular and genomic levels. The monitoring of acetaldehyde gas at low concentrations requires fast-response and low-cost sensors. Herein, we propose the design of an acetaldehyde gas sensor based on a low-cost Microelectromechanical System (MEMS) process.

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Triboelectric nanogenerators (TENGs) based on organic materials can harvest green energy to convert it into electrical energy. These nanogenerators could be used for Internet-of-Things (IoT) devices, substituting solid-state chemical batteries that have toxic materials and limited-service time. Herein, we develop a portable triboelectric nanogenerator based on dehydrated nopal powder (NOP-TENG) as novel triboelectric material.

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Cryptography has become one of the vital disciplines for information technology such as IoT (Internet Of Things), IIoT (Industrial Internet Of Things), I4.0 (Industry 4.0), and automotive applications.

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The latest generation of communication networks, such as SDVN (Software-defined vehicular network) and VANETs (Vehicular ad-hoc networks), should evaluate their communication channels to adapt their behavior. The quality of the communication in data networks depends on the behavior of the transmission channel selected to send the information. Transmission channels can be affected by diverse problems ranging from physical phenomena (e.

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Precise prediction of mechanical behavior of thin films at the nanoscale requires techniques that consider size effects and fabrication-related issues. Here, we propose a test methodology to estimate the Young's modulus of nanometer-thick films using micromachined bilayer cantilevers. The bilayer cantilevers which comprise a well-known reference layer and a tested film deflect due to the relief of the residual stresses generated during the fabrication process.

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Piezoelectric nanogenerators can convert energy from ambient vibrations into electrical energy. In the future, these nanogenerators could substitute conventional electrochemical batteries to supply electrical energy to consumer electronics. The optimal design of nanogenerators is fundamental in order to achieve their best electromechanical behavior.

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Piezoelectric vibration energy harvesting (pVEH) microdevices can convert the mechanical vibrations to electrical voltages. In the future, these microdevices can provide an alternative to replace the electrochemical batteries, which cause contamination due to their toxic materials. We present the electromechanical modeling of a pVEH microdevice with a novel resonant structure for air conditioning vents at office buildings.

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Cytotoxicity of titanium dioxide (TiO₂) thin films on Chinese hamster ovary (CHO-K1) cells was evaluated after 24, 48 and 72 h of culture. The TiO₂ thin films were deposited using direct current magnetron sputtering. These films were post-deposition annealed at different temperatures (300, 500 and 800 °C) toward the anatase to rutile phase transformation.

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Endoscopic optical-coherence tomography (OCT) systems require low cost mirrors with small footprint size, out-of-plane deflections and low bias voltage. These requirements can be achieved with electrothermal actuators based on microelectromechanical systems (MEMS). We present the design and modeling of polysilicon electrothermal actuators for a MEMS mirror (100 μm × 100 μm × 2.

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We present the study of the biocompatibility and surface properties of titanium dioxide (TiO₂) thin films deposited by direct current magnetron sputtering. These films are deposited on a quartz substrate at room temperature and annealed with different temperatures (100, 300, 500, 800 and 1100 °C). The biocompatibility of the TiO₂ thin films is analyzed using primary cultures of dorsal root ganglion (DRG) of Wistar rats, whose neurons are incubated on the TiO₂ thin films and on a control substrate during 18 to 24 h.

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We present an alternative post-processing on a CMOS chip to release a planar microelectrode array (pMEA) integrated with its signal readout circuit, which can be used for monitoring the neuronal activity of vestibular ganglion neurons in newborn Wistar strain rats. This chip is fabricated through a 0.6 μm CMOS standard process and it has 12 pMEA through a 4 × 3 electrodes matrix.

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