Indium Selenide (InSe) has attracted significant attention due to large tunability in the band gap, high carrier mobility and unique anisotropic optical properties compared to other twodimensional (2D), graphene, based systems for chemical and gas sensing applications in the hostile environments. The expanded research requires integrating the chemical and gas sensing capability with optical sensing function. Therefore, in this work, we report the integration and characterization of this material as field-effect transistor (FET) device and as an optical sensor.
A 28GHz Doherty Power Amplifier (DPA) is implemented in 22nm FDSOI CMOS. The DPA adopts the asymmetrical topology utilizing two-stack FET amplifiers as the main and auxiliary. This allows a voltage of 2.5V aiding high output power. The integrated design implements the main and auxiliary amplifier, along with the matching and transmission line networks on chip. The simulated design exhibits a peak power gain of 9.5dB and a peak power-added efficiency 18%(PAE). Keywords?Power Amplifiers, mm-wave, Doherty, 5G.
The effectiveness of the SWJ actuator like the AFC device is the ability to provide a high oscillatory jet. For this reason, an experimental study is conducted in order to determine the jet oscillation frequency which is a crucial parameter for effective separation control. A measurement of the static pressure is made on the upper feedback channel using Kulite XTL-140 series pressure transducer for an eight different inlet mass flow rates (from 1g/s to 8 g/s). Additionally, the baseline geometry is scaled by half (2:1) and by double (1:2) and pressure measurements are also performed in these scaled geometries. The results reveal a linear trend of the oscillating frequency versus the inlet mass flow rate and the inlet Mach number for all of the geometries. Moreover, computational simulations Ansys Fluent v17.2 software have been performed for comparison and reveal a high correspondence with experimental results. The smaller geometry creates higher frequencies than the double sized geometry for the same mass flow rate.
Spacecraft?s structural integrity is the critical criteria of mission success. The majority of CubeSat?s structures are made of Aluminum alloy. It has excellent workability and availability, however; it has a low yield strength value. Nano-satellites structures must be efficiently lightweight, thermally stable and has a low rate of outgassing. Therefore, composite materials are growing exponentially in the aerospace industry. This paper proposes innovative; 3D printed composite structure. Optimized fibers orientation and material density can be precisely designed to minimize the maximum stresses experienced by the CubeSat during the rocket launch stages. Finite Element Analysis tool (ANSYS) was conducted to assess the quasi-static loads and determine the vulnerable structural areas. The detrimental critical areas were the secondary (interior rods) and tertiary (flanges and supports) parts of the satellite structure. These vulnerable areas will be precisely optimized to sustain the higher loads; hence, 3D printed. Subsequently, standardized environmental testing will be performed to validate the structural integrity and thermal compatibility to the space environment; thermal vacuum testing and vibration testing (Sine Sweep and Random vibrations).
In the development of novel pharmaceutics and cell-mediated therapeutics, the immune system has to be well considered, as part of the response mechanism or as a potential collateral for drug toxicity. To reduce the attrition of such developments, the interaction of immune cells with drugs and/or with other cell types should be mechanistically investigated. As the lymph node (LN) is the integrating center for immune cells, whereby the body invokes responses against foreign substances, we have developed an artificial biomimetic LN, called LN-on-Chip, to facilitate investigations to cellular kinetics, cell-cell interactions and sampling. We recreated the biological scaffold and accurately reintroduced the cellular residents in a 3D distribution in the device. We demonstrated that the system replicates key features of the human LN, supports 3D cell culture in biomimetic matrices, and sustains cell viability for over 24 hours. The ultimate goal of this platform is to enable investigations into the effects of pharmaceutics to downstream immunology in more physiologically relevant microenvironments, thus, contributing to increased safety, lowered cost, and shorter cycles for drug development.
A magnetometer is a sensor that measures magnetic fields and uses their direction and intensity for telemetry and navigation. In this paper, a Z-axis Lorentz-force microelectromechanical (MEMS) magnetometer is introduced. The device is a resonant structure that has been designed for Q factor and resolution. The design has been modelled using Coventor?s MEMS+. A MATLAB and MEMS+ interfacing code has been utilized for design modeling and verification and to facilitate the design iteration and optimization process. The design has been shown to exhibit the desired motion in its first mode at a frequency of 668 kHz. Several parameters sweep of geometric design variables have been conducted in an effort to optimize the mechanical sensitivity of the device. The design has been fabricated using a MEMSCAP Silicon-On-Insulation (SOI) standard process and is currently undergoing testing and characterization at Khalifa University.
The built environment is expanding with the increase in population, urbanization and change in life style, all of this mostly requires concrete, the material responsible for 5% of global CO2 emissions and the second producer of greenhouse gases. Therefore, the need to create a more sustainable concrete that can accommodate the human growth without jeopardizing the environment or depleting natural resources. Utilizing waste within concrete has been researched as a double impact solution, creating a green concrete and a waste management technique. This paper reviews the utilization of agricultural waste within the concrete industry by looking at three options for integrating Agro-waste in concrete without compromising its performance. Agro-waste as coarse and/or fine aggregate, Agro-waste as partial or full replacement of Portland cement and Agro-waste as concrete fiber reinforcement. Available literature examines single application of Agro-waste, thus, compiling different approaches in one review will provide an objective and broad understanding of incorporating agricultural waste in concrete and all associated implications. Moreover, summarizing the optimal mixing percentages for each distinct application resulting in mechanical and/or thermal parity or even enhancement to conventional structural light weight concrete based on recent experimental research.
Cooling is considered one of the major energy consumers around the world. For example, air conditioning in Abu Dhabi makes up around 70% of the total electricity. Cooling process is mainly based on vapor compression refrigeration cycle and hence, to make the refrigeration cycle environmentally friendly, thermal energy storage by adsorption is a promising solution which can utilize waste heat energy for applications such as cooling, heating and many other utility applications. One of the major challenges in adsorption thermal energy storage applications is choosing the optimal working pairs (i.e. fluid and material) to obtain the most desirable and efficient adsorption system. Therefore, the objective of this project is to synthesize novel adsorptive materials (i.e. adsorbents) for cold energy storage that will give better energy storage capabilities based on waste heat energy or solar energy and thus contribute in producing an eco-friendly cooling process.
PVT properties are critical to petroleum reservoir characterization and management. This study investigates reservoir fluid phase behavior at different pressure drawdown conditions in the nearwellbore region using simulators and PVT studies. CMGs WINPROP package was used to analyze the phase behavior of the data set and generate component properties for compositional simulations using GEM. Also Eclipse PVT Package (PVTi) was used to simulate laboratory experiments in order to compare fluid samples for consistency. Four different PVT lab reports were used. WinProp was found to be more accurate in matching the laboratory results. PVTi produced unacceptably high differences. Regression was used to tune the equation of state to match experimental results in both simulators. Three of the PVT reports still had big differences between the GOR reported by the lab and the GOR calculated by the simulators both before and after regression. The calculated GORs in both simulators were comparable in both cases, so it is suspected there were errors on the PVT data. Further work with CMG reservoir simulator showed that inaccurate PVT results and/or poor sample quality could affect modeling near wellbore fluid behavior. This paper recommends best practices in using simulators to assist in validation of PVT data.
In this contribution, the soft-SAFT EoS, an equation of state based on Statistical Thermodynamics, was used to model the phase equilibria of carbon dioxide (CO2) and hydrogen sulfide (H2S) in aqueous monoethanolamine (MEA) at conditions of relevance for acid gas separation. The chemisorption of H2S in aqueous MEA was described in terms of the formation of H2Samine aggregates physically bounded by strong intermolecular association interactions, consistent with our previous works on the chemisorption of CO2. A maximum of two adjustable parameters, optimized for a fixed MEA concentration, sufficed to obtain an accurate representation of the absorption of H2S in aqueous MEA over a broad range of conditions. The developed model can predict the simultaneous absorption of H2S and CO2 in aqueous MEA solvent in good agreement with experimental literature data and comparable to those obtained from the recommended thermodynamic model (e-NRTL) available in Aspen Plus? engineering simulator. These results demonstrate the reliability of the model as a potential solvent screening tool for acid gas separation, owing to its high level of accuracy, transferability and predictive capabilities.
