scholarly journals Magnetic pulse processing of strawberries in the climatic chamber

2021 ◽  
Vol 247 ◽  
pp. 01038
Author(s):  
Dmitriy Khort ◽  
Alexey Kutyrev ◽  
Rostislav Filippov ◽  
Stepan Semichev
Keyword(s):  
Pulse Repetition Frequency ◽  
Experimental Studies ◽  
Low Frequency ◽  
High Sensitivity ◽  
Pulse Field ◽  
Physical Factors ◽  
Magnetic Pulse ◽  
Climatic Chamber ◽  
Energy Factors ◽  
The Relationship

The article presents the results of experimental studies on the magnetic pulse treatment of strawberries in a climatic chamber. The analysis of the obtained data showed that the greatest effect from the treatment of plants with a low-frequency magnetic pulse field in the phase of peduncle formation was obtained on plants that were treated with a magnetic induction equal to 4 MT, a pulse repetition frequency of 32 Hz and a duty cycle of 20. The relationship between the parameters of low-frequency magnetic pulse radiation and the photosynthetic activity of the leaf apparatus at various stages of ontogenesis, and the qualitative composition of fruits at the stage of maturation is revealed. The high sensitivity of plant organisms to the effects of energy factors, the parameters of which differ in exposure and physical factors, is shown. At the same time, the nature of the response of plants is complex, ambiguous and is determined not only by the electrophysical parameters of the electric field, but also by the specific, varietal and technological features of the crop.

scholarly journals Device for automated magnetic pulse stimulation of plant production processes

2020 ◽  
Vol 161 ◽  
pp. 01064
Author(s):  
Dmitriy Khort ◽  
Igor Smirnov ◽  
Alexey Kutyrev ◽  
Rostislav Filippov
Keyword(s):  
Magnetic Field ◽  
Plant Immunity ◽  
Low Frequency ◽  
Electrical Circuit ◽  
Plant Production ◽  
Physical Factors ◽  
Magnetic Pulse ◽  
Spiral Coil ◽  
Frequency Magnetic Field ◽  
Flat Spiral

Numerous studies of various physical factors show the promise of using pulsed magnetic fields in bioregulatory technologies to stimulate plant life and growth processes. As a result of exposure to garden strawberries with a low-frequency magnetic field, the quality of planting material improves, plant immunity increases, crop growth and development accelerates, the number and weight of berries increase. The article presents a developed automated device for magnetic pulse processing (MPP) of plants, considers the device, design and principle of its operation. The electrical circuit of the device and its technical characteristics are given. According to the results of a laboratory experiment, the magnetic field parameters of the working body of the device in the near zone of a flat spiral coil were established. The numerical value of the magnetic induction at a distance of 100 mm from the center of the coil is 8.3 mT.

DETERMINATION OF THE INFLUENCE OF STRUCTURAL ELEMENTS ON ACOUSTIC EFFICIENCY AND BACK PRESSURE IN EXHAUST AND SUCTION NOISE SILENCERS

Akustika ◽  
2021 ◽  
pp. 210-216
Author(s):  
Nickolay Ivanov ◽  
Aleksandr Shashurin ◽  
Aleksandr Burakov
Keyword(s):  
Structural Design ◽  
High Frequency ◽  
Experimental Studies ◽  
Low Frequency ◽  
Back Pressure ◽  
Noise Generation ◽  
Structural Elements ◽  
The Relationship

The features of noise generation processes in exhaust and suction noise silencers are shown. A method for testing silencers has been developed. The classification of the main structural elements of exhaust and suction noise silencers, depending on the purpose, is proposed. Experimental studies of the relationship between the acoustic efficiency and the back pressure of silencers from the structural design of the elements are performed. The factors influencing the efficiency in the low-frequency and high-frequency regions of the spectrum are determined: the volume of silencers, the number of chambers, perforation, sound absorption, flow ejection, etc. Recommendations for the design of noise silencers are proposed.

scholarly journals Evaluation of the Thermofluidic Performance of Climatic Chambers: Numerical and Experimental Studies

Fluids ◽  
2021 ◽  
Vol 6 (12) ◽  
pp. 433
Author(s):  
Bahareh Ramezani ◽  
António Tadeu ◽  
Tiago Jesus ◽  
Michael Brett ◽  
Joel Mendes
Keyword(s):  
Experimental Studies ◽  
Industrial Applications ◽  
Controlled Environment ◽  
Thermal Loss ◽  
Climatic Chamber ◽  
Ansys Fluent ◽  
Flow Heat ◽  
Computational Fluid Dynamics Cfd ◽  
The Relationship ◽  
Industrial Demand

Climatic chambers are highly important in research and industrial applications and are used to examine manufactured samples, specimens, or components in controlled environment conditions. Despite the growing industrial demand for climatic chambers, only a few published studies have specifically concentrated on performance analysis and functional improvements through numerical and experimental studies. In this study, a 3D computational fluid dynamics (CFD) model of a climatic chamber was developed using Ansys Fluent to simulate the fluid flow, heat, and mass transfer to obtain the velocity, temperature, and relative humidity fields in the interior box of a 1200 L climatic chamber. The results were then validated with experimental data from a prototype. Finally, the heat losses of the surrounding components of the chamber were calculated, and the relationship between the inside temperature and the overall thermal loss was modelled. This validated numerical model provides the possibility of optimising the performance of climate chambers by reducing the thermal loss from the walls and modifying the air flow pattern inside the chamber.

Practical High Resolution Microscopy

1968 ◽  
Vol 26 ◽  
pp. 302-303
Author(s):  
P. A. Marsh ◽  
T. Mullens ◽  
D. Price
Keyword(s):  
High Resolution ◽  
Magnetic Fields ◽  
Low Frequency ◽  
Resolving Power ◽  
Careful Attention ◽  
Electron Microscopes ◽  
The Relationship ◽  
High Resolution Microscopy ◽  
New Facilities

It is possible to exceed the guaranteed resolution on most electron microscopes by careful attention to microscope parameters essential for high resolution work. While our experience is related to a Philips EM-200, we hope that some of these comments will apply to all electron microscopes.The first considerations are vibration and magnetic fields. These are usually measured at the pre-installation survey and must be within specifications. It has been our experience, however, that these factors can be greatly influenced by the new facilities and therefore must be rechecked after the installation is completed. The relationship between the resolving power of an EM-200 and the maximum tolerable low frequency interference fields in milli-Oerstedt is 10 Å - 1.9, 8 Å - 1.4, 6 Å - 0.8.

Calculation-and-experimental estimation of the role of the frequency ratio in changing the endurance at two-frequency deformation modes

2019 ◽  
Vol 85 (1(I)) ◽  
pp. 64-71 ◽  
Author(s):  
M. M. Gadenin
Keyword(s):  
High Frequency ◽  
Experimental Studies ◽  
Low Frequency ◽  
Reduction Factor ◽  
Single Frequency ◽  
Cyclic Loads ◽  
Small Ratio ◽  
Harmonic Components ◽  
Deformation Modes

The cycle configuration at two-frequency loading regimes depends on the number of parameters including the absolute values of the frequencies and amplitudes of the low-frequency and high-frequency loads added during this mode, the ratio of their frequencies and amplitudes, as well as the phase shift between these harmonic components, the latter having a significant effect only with a small ratio of frequencies. Presence of such two-frequency regimes or service loading conditions for parts of machines and structures schematized by them can significantly reduce their endurance. Using the results of experimental studies of changes in the endurance of a two-frequency loading of specimens of cyclically stable, cyclically softened and cyclically hardened steels under rigid conditions we have shown that decrease in the endurance under the aforementioned conditions depends on the ratio of frequencies and amplitudes of operation low-frequency low-cycle and high-frequency vibration stresses, and, moreover, the higher the level of the ratios of amplitudes and frequencies of those stacked harmonic processes of loading the greater the effect. It is shown that estimation of such a decrease in the endurance compared to a single frequency loading equal in the total stress (strains) amplitudes can be carried out using an exponential expression coupling those endurances through a parameter (reduction factor) containing the ratio of frequencies and amplitudes of operation cyclic loads and characteristic of the material. The reduction is illustrated by a set of calculation-experimental curves on the corresponding diagrams for each of the considered types of materials and compared with the experimental data.

Risk assessment of occupational and occupationally conditioned diseases connection to noise when exceeding maximum permissible levels

2019 ◽  
pp. 17-19
Author(s):  
Vladimir A. Fokin ◽  
Dmitrii M. Shlyapnikov ◽  
Svetlana V. Red’ko
Keyword(s):  
Blood Pressure ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
High Blood Pressure ◽  
Noise Exposure ◽  
Physical Factors ◽  
Autonomic Nervous ◽  
Permissible Levels ◽  
The Relationship ◽  
Perm Region

In accordance with the requirements of paragraph 3.2.6 of sanitary rules and norms «Sanitary and epidemiological requirements for physical factors at workplace», in the event of exceeding noise level at workplace above 80 dBA, an employer is obliged to assess the health risk of workers and confirm an acceptable risk to their health. The connection between the incidence of occupational and occupationally conditioned diseases with noise exposure exceeding the maximum permissible levels (80 dBA) was estimated. The assessment was carried out at a food industry enterprise of Perm Region. Assessing the relationship between morbidity and noise exposure is the first step in evaluation of occupational health risks for workers exposed to noise exceeding MAL. If a reliable relationship between morbidity and noise exposure is established, an assessment of occupational risk is conducted. The odds ratio (OR) for diseases characterized by high blood pressure and disorders of autonomic nervous system was <1 (confidence interval CI=0.11–1.61 and CI=0.08–2.78, respectively). The relative risk (RR) for diseases characterized by high blood pressure and disorders of autonomic nervous system was <1. The received data testify absence of connection of morbidity with exposure to industrial noise, calculation of etiological share of responses and levels of risk is not required.

Potential Role of Inflammation in Associations between Particulate Matter and Heart Failure

2018 ◽  
Vol 24 (3) ◽  
pp. 341-358 ◽  
Author(s):  
Xiaotong Ji ◽  
Yingying Zhang ◽  
Guangke Li ◽  
Nan Sang
Keyword(s):  
Heart Failure ◽  
Particulate Matter ◽  
Inflammatory Response ◽  
Heart Diseases ◽  
Experimental Studies ◽  
Epidemiological Studies ◽  
Inflammatory Mechanism ◽  
High Concentrations ◽  
Future Work ◽  
The Relationship

Recently, numerous studies have found that particulate matter (PM) exposure is correlated with increased hospitalization and mortality from heart failure (HF). In addition to problems with circulation, HF patients often display high expression of cytokines in the failing heart. Thus, as a recurring heart problem, HF is thought to be a disorder characterized in part by the inflammatory response. In this review, we intend to discuss the relationship between PM exposure and HF that is based on inflammatory mechanism and to provide a comprehensive, updated evaluation of the related studies. Epidemiological studies on PM-induced heart diseases are focused on high concentrations of PM, high pollutant load exposure in winter, or susceptible groups with heart diseases, etc. Furthermore, it appears that the relationship between fine or ultrafine PM and HF is stronger than that between HF and coarse PM. However, fewer studies paid attention to PM components. As for experimental studies, it is worth noting that coarse PM may indirectly promote the inflammatory response in the heart through systematic circulation of cytokines produced primarily in the lungs, while ultrafine PM and its components can enter circulation and further induce inflammation directly in the heart. In terms of PM exposure and enhanced inflammation during the pathogenesis of HF, this article reviews the following mechanisms: hemodynamics, oxidative stress, Toll-like receptors (TLRs) and epigenetic regulation. However, many problems are still unsolved, and future work will be needed to clarify the complex biologic mechanisms and to identify the specific components of PM responsible for adverse effects on heart health.

scholarly journals Experimental studies on the transformation from firn to ice in the wet-snow zone of temperate glaciers

1997 ◽  
Vol 24 ◽  
pp. 181-185 ◽  
Author(s):  
Katsuhisa Kawashima ◽  
Tomomi Yamada
Keyword(s):  
Experimental Studies ◽  
Ice Formation ◽  
Compression Tests ◽  
Densification Rate ◽  
Overburden Pressure ◽  
Proportionality Constant ◽  
Wet Snow ◽  
Water Saturated ◽  
The Relationship ◽  
Good Agreement

The densification of water-saturated firn, which had formed just above the firn-ice transition in the wet-snow zone of temperate glaciers, was investigated by compression tests under pressures ranging from 0.036 to 0.173 MPa, with special reference to the relationship between densification rate, time and pressure. At each test, the logarithm of the densification rate was proportional to the logarithm of the time, and its proportionality constant increased exponentially with increasing pressure. The time necessary for ice formation in the firn aquifer was calculated using the empirical formula obtained from the tests. Consequently, the necessary time decreased exponentially as the pressure increased, which shows that the transformation from firn in ice can be completed within the period when the firn aquifer exists, if the overburden pressure acting on the water-saturated firn is above 0.12–0.14 MPa. This critical value of pressure was in good agreement with the overburden pressure obtained from depth–density curves of temperate glaciers. It was concluded that the depth of firn–ice transition was self-balanced by the overburden pressure to result in the concentration between 20 and 30 m.

scholarly journals Magnetoelastic Coupling and Delta-E Effect in Magnetoelectric Torsion Mode Resonators

Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 2022
Author(s):  
Benjamin Spetzler ◽  
Elizaveta V. Golubeva ◽  
Ron-Marco Friedrich ◽  
Sebastian Zabel ◽  
Christine Kirchhof ◽  
...  
Keyword(s):  
Low Frequency ◽  
High Sensitivity ◽  
Element Model ◽  
Mode Number ◽  
Frequency Change ◽  
General Description ◽  
Resonance Modes ◽  
Field Sensor ◽  
Magnetic Sensitivity ◽  
Bending Modes

Magnetoelectric resonators have been studied for the detection of small amplitude and low frequency magnetic fields via the delta-E effect, mainly in fundamental bending or bulk resonance modes. Here, we present an experimental and theoretical investigation of magnetoelectric thin-film cantilevers that can be operated in bending modes (BMs) and torsion modes (TMs) as a magnetic field sensor. A magnetoelastic macrospin model is combined with an electromechanical finite element model and a general description of the delta-E effect of all stiffness tensor components Cij is derived. Simulations confirm quantitatively that the delta-E effect of the C66 component has the promising potential of significantly increasing the magnetic sensitivity and the maximum normalized frequency change ∆fr. However, the electrical excitation of TMs remains challenging and is found to significantly diminish the gain in sensitivity. Experiments reveal the dependency of the sensitivity and ∆fr of TMs on the mode number, which differs fundamentally from BMs and is well explained by our model. Because the contribution of C11 to the TMs increases with the mode number, the first-order TM yields the highest magnetic sensitivity. Overall, general insights are gained for the design of high-sensitivity delta-E effect sensors, as well as for frequency tunable devices based on the delta-E effect.

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