Large pressure-induced magnetoresistance in a hybrid ferromagnet-semiconductor system: Effect of matrix modification on the spin-dependent scattering

Hypobaric effects on the perilymph pressure were investigated in 18 cats. The perilymph, tympanic cavity, cerebrospinal fluid, and systemic and ambient pressure changes were continuously recorded relative to the atmospheric pressure. The pressure equilibration of the eustachian tube and the cochlear aqueduct was studied, as well as the effects of blocking these channels. During ascent, the physiologic opening of the eustachian tube reduced the pressure gradients across the tympanic membrane. The patent cochlear aqueduct equilibrated perilymph pressure to cerebrospinal fluid compartment levels with a considerable pressure gradient across the oval and round windows. With the aqueduct blocked, the pressure decrease within the labyrinth and tympanic cavities was limited, resulting in large pressure gradients toward the chamber and the cerebrospinal fluid compartments, respectively. We conclude that closed cavities with limited pressure release capacities are the cause of the pressure gradients. The strain exerted by these pressure gradients is potentially harmful to the ear.

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Analysis of Flow Characteristics and Effects of Turbulence Models for the Butterfly Valve

Applied Sciences ◽

10.3390/app11146319 ◽

2021 ◽

Vol 11 (14) ◽

pp. 6319

Author(s):

Sung-Woong Choi ◽

Hyoung-Seock Seo ◽

Han-Sang Kim

Keyword(s):

Turbulence Model ◽

Dissipation Rate ◽

Flow Characteristics ◽

Turbulence Models ◽

Flow Properties ◽

Nominal Diameter ◽

Large Pressure ◽

Sst Model ◽

Turbulence Effect ◽

Valve Opening

In the present study, the flow characteristics of butterfly valves with different sizes DN 80 (nominal diameter: 76.2 mm), DN 262 (nominal diameter: 254 mm), DN 400 (nominal diameter: 406 mm) were numerically investigated under different valve opening percentages. Representative two-equation turbulence models of two-equation k-epsilon model of Launder and Sharma, two-equation k-omega model of Wilcox, and two-equation k-omega SST model of Menter were selected. Flow characteristics of butterfly valves were examined to determine turbulence model effects. It was determined that increasing turbulence effect could cause many discrepancies between turbulence models, especially in areas with large pressure drop and velocity increase. In addition, sensitivity analysis of flow properties was conducted to determine the effect of constants used in each turbulence model. It was observed that the most sensitive flow properties were turbulence dissipation rate (Epsilon) for the k-epsilon turbulence model and turbulence specific dissipation rate (Omega) for the k-omega turbulence model.

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Caste stone formation in the MgO-H2O-organo system – Effect of citric, malic or acetic acid and MgO reactivity on type and composition of castables

Case Studies in Construction Materials ◽

10.1016/j.cscm.2021.e00606 ◽

2021 ◽

pp. e00606

Author(s):

Sabrina Gerger ◽

Andre Baldermann ◽

Martin Dietzel

Keyword(s):

Acetic Acid ◽

Stone Formation ◽

System Effect

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Progresses in Food Packaging, Food Quality, and Safety—Controlled-Release Antioxidant and/or Antimicrobial Packaging

Molecules ◽

10.3390/molecules26051263 ◽

2021 ◽

Vol 26 (5) ◽

pp. 1263

Author(s):

Cornelia Vasile ◽

Mihaela Baican

Keyword(s):

Food Quality ◽

Food Packaging ◽

Life Extension ◽

Quality And Safety ◽

Testing Methods ◽

Food Handling ◽

Active Food Packaging ◽

Matrix Modification ◽

Radiofrequency Identification ◽

Food Quality And Safety

Food packaging is designed to protect foods, to provide required information about the food, and to make food handling convenient for distribution to consumers. Packaging has a crucial role in the process of food quality, safety, and shelf-life extension. Possible interactions between food and packaging are important in what is concerning food quality and safety. This review tries to offer a picture of the most important types of active packaging emphasizing the controlled/target release antimicrobial and/or antioxidant packaging including system design, different methods of polymer matrix modification, and processing. The testing methods for the appreciation of the performance of active food packaging, as well as mechanisms and kinetics implied in active compounds release, are summarized. During the last years, many fast advancements in packaging technology appeared, including intelligent or smart packaging (IOSP), (i.e., time–temperature indicators (TTIs), gas indicators, radiofrequency identification (RFID), and others). Legislation is also discussed.

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