Material and chemical stability of using motor gasoline/automotive gasoline in piston engine aircrafts – a review

Background and Aim: Extending the shelf life of foods is an essential concept in food safety. Most of the time, foods deteriorate through the growth of microorganisms or oxidation process. Essential oils (EOs) derived from plant material have well-documented antioxidant and antibacterial activity. This study aimed to evaluate the effect of Zataria multiflora Boiss EO (ZEO) and Mentha piperita EO (MEO) on the chemical stability of minced meat during storage at 7°C. Materials and Methods: Total phenolic content, β-Carotene bleaching test, ferric reducing antioxidant potential assay, and 2,2-Diphenyl-1-picrylhydrazyl radical scavenging activity were used to determine the antioxidant potential of EOs. Five different groups including control, ZEO 0.3%, ZEO 0.5%, MEO 0.3%, and MEO 0.5% were designed to assess the chemical stability of minced meat by measuring pH, thiobarbituric acid (TBA), total volatile base nitrogen (TVBN), and peroxide value (PV). Results: pH did not have any significant change during storage. TBA values in the control group were significantly higher than the treatment groups, especially from the 5th day of storage. TVBN in the treatment group was significantly lower than the control group during storage. PV values in the treatment group were significantly lower than the control group during storage. Conclusion: Results indicate that ZEO and MEO had an excellent antioxidant activity and retarded the spoilage process in minced meat. Keywords: antioxidant, Mentha piperita, minced meat, Zataria multiflora Boiss.

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Research on sealing characteristics of annular power cylinder based on twin-rotor piston engine

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/09544062211021440 ◽

2021 ◽

pp. 095440622110214

Author(s):

Dibo Pan ◽

Haijun Xu ◽

Bolong Liu ◽

Congnan Yang

Keyword(s):

Compression Ratio ◽

Simulation Analysis ◽

Piston Engine ◽

Leakage Model ◽

Gas Leakage ◽

Power Cylinder ◽

Sealing Performance ◽

Piston Seal ◽

Realization Process ◽

Twin Rotor

The sealing characteristics of an annular power cylinder based on the Twin-rotor piston engine are studied, which provides a theoretical foundation for the sealing design of a new high-power density piston engine. In this paper, the basis thermodynamic realization process of an annular power cylinder is presented. The Runge Kutta equation is used to establish the coupled leakage model of adjacent working chambers under annular piston seal. And the sealing performance of the annular power cylinder is analyzed in detail. Moreover, the influence of rotor speed and compression ratio on the sealing characteristics and leakage is studied. Finally, some tests are carried out to verify the sealing principle and simulation results, which verifies the theoretical basis of simulation analysis. Results show that there are double pressure peaks in the leakage chamber between two working chambers, which is beneficial to reduce the leakage rate. Besides, increasing the speed and decreasing the compression ratio can help to reduce gas leakage. Furthermore, the effects of speed variation on the leakage are only significant when rotating at low speed. Changing the compression ratio has a greater effect on the slope of the leakage curve at a low compression ratio, and the lower the compression ratio, the better the sealing effect.

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A matrix targeted fluorescent probe to monitor mitochondrial dynamics

Organic & Biomolecular Chemistry ◽

10.1039/d0ob02128h ◽

2021 ◽

Author(s):

Madhu Ramesh ◽

Kolla Rajasekhar ◽

Kavya Gupta ◽

Vardhaman Babagond ◽

Deepak Kumar Saini ◽

...

Keyword(s):

Fluorescent Probe ◽

Chemical Stability ◽

Mitochondrial Dynamics ◽

Mitochondrial Matrix ◽

Turn On

A far-red turn-on fluorescent probe (Mito-TG) with excellent biocompatibility, photostability, chemical stability targets mitochondrial matrix. The insensitivity of probe under different pH and ROS enabled tracking of mitophagy and Aβ induced mitochondrial dynamics.

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