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Temperature-Responsive Poly(Vinyl Alcohol)-Borax Salogels for Shape Stabilization of an Inorganic Phase Change Material
Get PDFA temperature-responsive gel has been introduced to achieve shape stabilization of phase change materials (PCMs). Inorganic salt hydrates are promising PCMs, but their low viscosity at temperatures above their melting point leads to leakage and corrosion in thermal storage modules. Temperature-responsive salogels can trap inorganic salt hydrates to achieve shape stabilization when the temperature is lower than the gel-sol transition temperature (Tgel) to overcome the leakage problem. Increasing the temperature above Tgel transforms the system to the liquid state enabling easy removal of the PCM material from the thermal storage units. This work focuses on the salogels system consisting of poly(vinyl alcohol) (PVA) dissolved in calcium nitrate tetrahydrate (CNH). Through variations in molecular weight, degree of hydrolysis, and concentration of PVA, precise control of Tgel of the salogel was achieved. Importantly, at the matched PVA concentrations, gelation occurred in CNH but not in water. This difference is rationalized by the unique features of CNH as a solvent, such as an extremely high salt content and scarcity of water. Interactions of PVA and solvent were investigated using attenuated total reflection Fourier Transform Infrared spectroscopy (ATR-FTIR), and a suggested mechanism of gelation of PVA in CNH is discussed. To further enhance the salogel strength and improve control over the gelation temperature, borax as a crosslinker that forms dynamic covalent bonds with PVA was introduced. PVA/borax/CNH salogels could achieve Tgel as high as 70��C using 3 wt% PVA and as low as ~0.3 wt% concentration of borax. The crosslinking mechanism of borax and PVA in CNH involves formation of dynamic covalent borate ester bonds, which lead to salogel strengthening. Compared to traditional PVA-borax hydrogels in water, PVA-borax salogels in CNH showed the unique feature of highly repeatable temperature reversibility. In addition, the reported salogels not only provide shape stabilization of CNH but also exhibit robust self-healing properties
U.S.S. Constitution Ship Model
No full textCase dimensions: 53" x 37"On loan from the Houston Maritime Museum. In a large case with description of the ship
Multifunctional Telecollaboration Interface for Mobile Soft Robots
No full textAs robotic technology advances mobile soft robots have become a recent topic of research, presenting unique capabilities that enhance the versatility and adaptability of robots. Characterized by their flexibility, adaptability, and inherent safety, mobile soft robots can traverse diverse terrains, manipulate objects with varying shapes and sizes, and safely interact with humans and the environment. Their features allow them to be better for certain applications, such as search and rescue, exploration, and human-robot collaboration tasks. Despite these advantages, the robots still face a unique challenge in regards to controlling them, and a lack of research in regards to telecollaborative devices designed for them. An intuitive, and reliable collaboration interface can enable operators to leverage the full potential of mobile soft robots. This interface becomes even more crucial when the robot is deployed in dynamic environments, where precise responses are important. This work focuses on the development of a telecollaborative device designed to handle the unique capabilities of mobile soft robots. By investigating different control methods, communication models, and feedback mechanisms, it aims to bring human-robot collaboration into mobile soft robots, expanding the effectiveness of mobile soft robots in real-world applications. This thesis presents the design and development of a multi-functional telecollaboration device for mobile soft robots. The device is a handheld interface with reprogramming capability to control different types of mobile soft robots. Wireless communication is employed to connect the telecollaboration device to the robots, enabling the duplex transmission of locomotion gaits, sensor data, and video feeds. The successful implementation of the teleoperation device affirms the ability to improve control in regard to mobile soft robots allowing more people to engage effectively with mobile soft robotics in real-world scenarios
Wireless Sensor Network for Real-time Substation Equipment Monitoring
No full textThe main objective of this research thesis is to provide real-time monitoring of the status of substations of power systems by wireless transmission from a substation to a control center in real time. This will not only reduce the amount of labor that is being deployed at each substation to record data manually but also replace wired communication with wireless using Long-Term Evolution (LTE)/4G Technology. The process starts from the substation, the data and readings are sent to the microcontroller that works on CANbus and Modbus interfaces which then sends the data being collected in real-time to the server. The server processes and stores the data in the database, waiting for a request from the client to respond with the needed data. After the request is sent from the client, who in this case is the web interface, to the server, then a response is sent to the web interface. The data is received by the web interface and is further processed and displayed on the browser as plots or tables. This allows engineers to virtually monitor the status of substations easily without having to physically visit the substations to get the information needed. Multiple steps were taken with the integration of the data collected from the microcontroller to the server, and corresponding ports were used for the web app and the microcontroller to allow them to communicate in real-time. Encryption will be used to make sure all the data that is traveling between the components is protected and no other external entity can access them
Early Detection of Oral Squamous Cell Carcinoma Through Salivary Analysis
Get PDFOral cancer ranks as the sixth most prevalent type globally, with oral squamous cell carcinoma (OSCC) accounting for most of it. Despite the ease of examining the oral cavity in clinical settings, most OSCC cases are not diagnosed in their early stages, which significantly contributes to the low survival rate. Presently, the standard method for diagnosing OSCC is through histological examination. However, recent research has explored the potential of non-invasive approaches, like saliva diagnostics, to detect specific biomarkers in saliva from individuals with OSCC. Analyzing the highly specific components in saliva, such as cytokines, circulating tumor DNA (ctDNA), and matrix metalloproteinases (MMPs), could result in early detection of OSCC. Therefore, the objective of this review is to present the latest findings regarding the detection of saliva biomarkers in various patient types and suggest potential biomarkers that prove to be reliable, specific, and sensitive for the early detection and management of OSCC. Saliva diagnostics, or ���liquid biopsy���, is painless, easily accessible, cost-effective, and serves as a valuable resource for identifying biomarkers. Although further research is needed to determine the effectiveness and limitations of salivary biomarkers, research suggests that saliva diagnostics could be effectively integrated into future clinical diagnostic processes, leading to significant improvements in early detection of OSCC, serving as the first step towards a more favorable outcome. These salivary biomarkers also can detect other cancer types and even monitor the activity of non-cancerous diseases
