How helical coil effect the heat transfer coefficient in two phase flow boiling.?5 answersHelical coils significantly impact the heat transfer coefficient in two-phase flow boiling. The coil diameter plays a crucial role in affecting pressure drop and non-uniform circumferential heat transfer, with smaller coil diameters showing more pronounced effects on heat transfer enhancement. Geometric parameters like coil diameter and pitch, along with operating conditions such as mass flux and vapor quality, influence heat transfer characteristics during condensation and boiling in helical coils. Additionally, the Nusselt number decreases with increasing heat flux during condensation due to the turbulence effect created by secondary flow in helically coiled tubes, which eliminates density-related effects. Numerical analyses of helical coil heat exchangers further explore the impact of D/d ratios on heat transfer rates and pumping power, providing insights into optimal heat transfer conditions for different boundary conditions.
What is the effect of pulsed electromagnetic fields on the brain?4 answersPulsed electromagnetic fields (PEMFs) have been shown to have various effects on the brain. They act as modulators of adenosine receptors, increasing the functionality of endogenous adenosine. PEMF exposure induces upregulation of A2A and A3 adenosine receptors in different neuronal cell types. PEMFs counteract hypoxia-induced apoptosis and ROS production in neuronal-like cells and exert a strong anti-inflammatory effect on microglial cells. In stroke animal models, PEMFs exposure reduces the size of the infarct area and decreases the levels of pro-inflammatory mediators. Preliminary results on acute ischemic stroke patients showed a dose-dependent reduction in the lesion size. PEMFs also affect neuronal differentiation and promote cell survival through the Akt/Ras signaling pathway. Additionally, PEMF exposure impairs spatial learning and memory ability and disturbs neuronal activities in the hippocampal CA1 area.
What are the effects of using COIL in teacher education?4 answersCOIL has been found to have positive effects on teacher education. It promotes the development of intercultural competencies and technological skills. COIL allows teachers to create inclusive and innovative learning environments that value and celebrate cultural differences. It also enhances learning by incorporating diverse perspectives and unique experiences. Successful implementation of COIL requires training and institutional support for teachers, as well as proficiency in another language. COIL can be used as a methodology for online teaching and learning, providing opportunities for collaboration between students from different countries. It encourages the use of technology and active teaching methods, such as the "Clases Espejo" approach. Instructors involved in COIL projects need to have knowledge of content, pedagogy, technology, and cultural differences. Overall, COIL in teacher education fosters intercultural understanding and the acquisition of digital skills.
What effect does the copper coil have?5 answersThe copper coil has various effects depending on its application. In the context of magnetic energy storage with conduction cooling, the presence of thermally conducting copper support structures in conduction-cooled coils can modify the resistances and inductances seen by front-end converters. Copper coils can also be used for harvesting electromagnetic (EM) waves from the atmosphere to create voltage, which can be utilized as a power source for micro/nano systems, thrusters, and deep space propulsion probes. In the case of a copper coil pipe for a solar air conditioner, the structure of the coil pipe enhances heat exchange efficiency by changing the flowing state of fluid and increasing the heat exchange rate. Additionally, a composite magnetorheological elastomer (MRE) embedded with a copper coil can improve the field-dependent properties of the MRE and increase the utilization ratio of the magnetic field. Finally, a transformer coil structure adopting copper foils reduces the material for producing an iron core and the no-load loss of a transformer.
What is pulsed electric field?3 answersPulsed electric field (PEF) is a non-thermal food processing technique that uses electric pulses to treat food products. It has advantages over conventional thermal processing methods as it preserves the sensory and nutritional properties of food while producing fresh-like food. PEF is also cost-effective, environmentally safe, and can be scaled up for industrial applications. In addition to food processing, PEF has been investigated for its potential in cell membrane perturbation, leading to applications such as cell lysis, drug delivery, and gene transfer. PEF has regulatory approval for pasteurization equivalence of fruit juices and has shown potential for use in liquid foods, including milk, for microbial inactivation and food safety applications. However, further research and development are needed to optimize PEF treatment systems and understand the factors that influence its efficacy in different applications. PEF has also been explored in cheesemaking, where it can affect the destruction of pathogens, milk proteins and lipids, and the sensory properties of cheese.
What are the potential benefits of pulsed electromagnetic field therapy?4 answersPulsed electromagnetic field (PEMF) therapy has potential benefits in various areas of healthcare. It can be used to improve cellular and body functions, reduce the effects of cell and tissue injury, and decrease pain. PEMF therapy has been found to be effective in treating bone healing, wound healing, osteoarthritis, inflammation, and post-operative pain and edema. It is a safe and non-invasive treatment modality that can be used in veterinary care as well. In the field of oncology, PEMF therapy shows promise as a potential therapeutic strategy due to its non-invasiveness, safety, lack of toxicity for non-cancerous cells, and potential for combination with other therapies. Although limited application of PEMF therapy in cancer has been documented in humans, experimental and clinical evidence supports its use and future perspectives in oncology.