scholarly journals Характеристики аэрозольного облака, образующегося при микровзрывном разрушении двухжидкостной капли

2019 ◽  
Vol 45 (16) ◽  
pp. 14
Author(s):  
Д.В. Антонов ◽  
Г.В. Кузнецов ◽  
П.А. Стрижак
Keyword(s):  
External Surface ◽  
Heating Temperature ◽  
Relative Concentration ◽  
Experimental Studies ◽  
External Surface Area ◽  
Asymptotic Nature ◽  
Video Registration ◽  
Initial Drop ◽  
Information Database ◽  
Two Fluid

The results of experimental studies of micro-explosion of two-fluid (water and rapeseed oil) droplets during heating in an air flow with a temperature of 250 to 450 oC are presented. As a result of video registration, an information database was obtained on the external surface area of the emerging aerosol cloud and the free surface of the liquid in comparison with the similar parameters of the initial drop. The dependences of these parameters on the heating temperature and the relative concentration (10–90 vol.%) of the combustible component in the droplet are established. The conditions for obtaining the asymptotic nature of these dependencies are determined.

scholarly journals The Amounts of Water Adsorbed to the Surface of Clay Minerals at the Plastic Limit

2017 ◽  
Vol 64 (3-4) ◽  
pp. 155-162
Author(s):  
Aleksandra Gorączko ◽  
Andrzej Olchawa
Keyword(s):  
Surface Area ◽  
External Surface ◽  
Solid Phase ◽  
Water System ◽  
Basal Spacing ◽  
Plastic Limit ◽  
X Ray Diffraction ◽  
External Surface Area ◽  
X Ray ◽  
Water Layers

AbstractThe paper presents results of a study on the amount of water associated with the solid phase of the clay water system at the plastic limit. Two model monomineral clays, namely kaolinite, and montmorillonite, were used in the study. The latter was obtained by gravitational sedimentation of Na-bentonite (Wyoming).The calculated mean number of water molecule layers on the external surface of montmorillonite was 14.4, and water in interlayer spaces constituted 0.3 of the water mass at the plastic limit.The number of water layers on the external surface of kaolinite particles was 63, which was related to the higher density of the surface electrical charge of kaolinite compared to that of montmorillonite.The calculations were made on the basis of the external surface area of clays and the basal spacing at the plastic limit measured by an X-ray diffraction test. The external surface area of clays was estimated by measuring sorption at a relative humidity p/p0 = 0.5.

Application of preliminary low-temperature heating for cold forming of complex parts on cold former

2021 ◽  
pp. 396-399
Author(s):  
V.Yu. Lavrinenko ◽  
Yu.A. Lavrinenko ◽  
R.S. Fayruzov ◽  
A.S. Ayrapetyan ◽  
A.S. Kirsanov
Keyword(s):  
Low Temperature ◽  
Heating Temperature ◽  
Experimental Studies ◽  
Life Time ◽  
Cold Forging ◽  
Flow Curves ◽  
Cold Forming ◽  
40Kh13 Steel ◽  
Temperature Heating ◽  
Complex Parts

The results of experimental studies of flow curves of 32CrB4, 20G2R and 1.4034 (analogue of 40Kh13 steel) steels at different heating temperature of workpieces are presented. Rational intervals of preliminary lowtemperature heating of workpieces made of studied steels are obtained. It allows to decrease forces during cold forging, loads on the working tool and to increase of tool life time up to 2 times.

scholarly journals Plasma Catalysis: Distinguishing between Thermal and Chemical Effects

Catalysts ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 185 ◽  
Author(s):  
Guido Giammaria ◽  
Gerard van Rooij ◽  
Leon Lefferts
Keyword(s):  
Gas Phase ◽  
Surface Area ◽  
Thermal Effects ◽  
External Surface ◽  
Plasma Chemistry ◽  
Internal Surface ◽  
Plasma Power ◽  
External Surface Area ◽  
Internal Surface Area ◽  
Chemical Effects

The goal of this study is to develop a method to distinguish between plasma chemistry and thermal effects in a Dielectric Barrier Discharge nonequilibrium plasma containing a packed bed of porous particles. Decomposition of CaCO3 in Ar plasma is used as a model reaction and CaCO3 samples were prepared with different external surface area, via the particle size, as well as with different internal surface area, via pore morphology. Also, the effect of the CO2 in gas phase on the formation of products during plasma enhanced decomposition is measured. The internal surface area is not exposed to plasma and relates to thermal effect only, whereas both plasma and thermal effects occur at the external surface area. Decomposition rates were in our case found to be influenced by internal surface changes only and thermal decomposition is concluded to dominate. This is further supported by the slow response in the CO2 concentration at a timescale of typically 1 minute upon changes in discharge power. The thermal effect is estimated based on the kinetics of the CaCO3 decomposition, resulting in a temperature increase within 80 °C for plasma power from 0 to 6 W. In contrast, CO2 dissociation to CO and O2 is controlled by plasma chemistry as this reaction is thermodynamically impossible without plasma, in agreement with fast response within a few seconds of the CO concentration when changing plasma power. CO forms exclusively via consecutive dissociation of CO2 in the gas phase and not directly from CaCO3. In ongoing work, this methodology is used to distinguish between thermal effects and plasma–chemical effects in more reactive plasma, containing, e.g., H2.

Device for Testing Pipe Billet

2020 ◽  
Vol 299 ◽  
pp. 1166-1171 ◽  
Author(s):  
Phyo Wai Aung ◽  
Maryin S. Borisovich
Keyword(s):  
Titanium Alloys ◽  
Heating Temperature ◽  
Experimental Studies ◽  
Protective Atmosphere ◽  
Pipeline Systems

Experimental studies of the influence of the heating temperature on the properties of pipe billets made of titanium alloys OT4 and OT4-1 in the formation of parts for the installation of pipeline systems without a protective atmosphere are presented.

Carbon-embedded mesoporous Nb-doped TiO2 nanofibers as catalyst support for the oxygen reduction reaction in PEM fuel cells

2016 ◽  
Vol 4 (17) ◽  
pp. 6540-6552 ◽  
Author(s):  
Esmaeil Navaei Alvar ◽  
Biao Zhou ◽  
S. Holger Eichhorn
Keyword(s):  
Titanium Dioxide ◽  
Oxygen Reduction Reaction ◽  
Polymer Coating ◽  
External Surface ◽  
Catalyst Support ◽  
Pem Fuel Cells ◽  
Reduction Reaction ◽  
External Surface Area ◽  
Tio2 Nanofibers ◽  
Doped Titanium Dioxide

Embedding carbon via polymer coating and reductive calcination to increase the conductivity and external surface area of mesoporous Nb-doped titanium dioxide nanofibers.

EXPERIMENTAL STUDIES OF THE HEATING TEMPERATURE OF THE GREENHOUSE RADIATOR INSTALLATIONS

2020 ◽  
Vol 15 (1) ◽  
pp. 76-80
Author(s):  
Nadezhda Kondrat'eva ◽  
Dmitriy Filatov ◽  
Pavel Terent'ev ◽  
Bulat Ziganshin
Keyword(s):  
Energy Efficiency ◽  
Supply Voltage ◽  
Heating Temperature ◽  
Experimental Studies ◽  
Maximum Temperature ◽  
Thermal Imager ◽  
Voltage Level ◽  
Radiation Sources ◽  
Measurement Results ◽  
Nominal Mode

The thermal regime of plants determines the temperature of the environment, the evaporation of moisture by plants, and the heating of plants by radiation from irradiation plants. Today, induction and LED greenhouse irradiators are promising for replacing irradiators with sodium lamps in terms of energy efficiency. Experimental studies were performed to assess the possibility of proximity of irradiators with induction lamps and LED irradiators to plants to increase their level of irradiation, in comparison with sodium radiation sources. When setting up the experiment, a complex was used, including a Fluke ti32 thermal imager, PHO-250-2-M linear autotransformer, 220V power supply, and a greenhouse irradiator. Processing of the measurement results was carried out in the Fluke SmartView 3.1 program. The heating temperature was determined when reaching the nominal mode, with the nominal mode of operation of the irradiators, with a change in the supply voltage level. Sodium and induction irradiators heat up to a maximum temperature 10 times faster than LED ones. The heating temperature of optical radiation sources with sodium lamps is 5 times higher than LED and 2.5 times higher than induction. A change in the supply voltage level affects the heating temperature of the sodium irradiator with electromagnetic ballasts, the heating temperature of sodium and induction irradiators with electronic ballasts, as well as LED irradiators, remains unchanged and equal to the nominal value at a supply voltage level of ± 10% of Unom.. Low heating temperatures of induction and LED irradiators can reduce the height of their suspension and bring them closer to plants, which will increase the irradiation of plants by increasing the level of illumination or reduce the power of irradiators, that is, increase the energy efficiency of irradiation systems

Surface Area of the Euphausiid Thysanöessa raschii and Its Relation to Body Length, Weight, and Respiration

1977 ◽  
Vol 34 (2) ◽  
pp. 225-231 ◽  
Author(s):  
Gareth C. H. Harding
Keyword(s):  
Oxygen Consumption ◽  
Metabolic Rate ◽  
Surface Area ◽  
Body Length ◽  
External Surface ◽  
Dry Weight ◽  
External Surface Area ◽  
Marine Crustaceans ◽  
Respiratory Surface ◽  
Wet Weight

A method is described for estimating the surface area of marine crustaceans. The external surface area of the euphausiid Thysanöessa raschii (M. Sars) is proportional to length2.4, dry weight0.95, and wet weight0.84. Oxygen consumption is proportional to wet weight0.82, which indicates that respiration should be proportional to respiratory surface area. The implications of this finding regarding the relations of metabolic rate, size, and surface area are discussed in a broader framework by comparing them with similar studies on vertebrates and other invertebrates.

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