scholarly journals Effect of Temperature and Prewetting for Ice Penetration with Sodium Formate

2020 ◽  
Vol 2674 (6) ◽  
pp. 140-150
Author(s):  
Mateusz Piotr Trzaskos ◽  
Alex Klein-Paste
Keyword(s):  
Waiting Time ◽  
Digital Image Analysis ◽  
Penetration Rate ◽  
Sodium Formate ◽  
Effect Of Temperature ◽  
Test Results ◽  
Penetration Process ◽  
Constant Rate ◽  
Different Temperatures ◽  
Penetration Tests

Granular sodium formate (NaCOOH) is a popular deicer used at airports. It is mainly used to weaken compacted snow/ice and thereby facilitate mechanical ice removal. Earlier research has developed a set of methods quantifying deicer performance, but linking these test results to operational guidelines is difficult. The main objective of this study is to increase the knowledge of how temperature and prewetting affect the ice penetration performance of granular sodium formate. A new method to evaluate the development of ice penetration process is presented here. Ice penetration tests were performed with single grains on large, optically clear ice cubes, and digital image analysis is used to quantify the initial waiting time, penetration rate and –depth, and melted volume. Eighteen tests including dry and prewetted sodium formate grains were performed at three different temperatures (–2°C, −5°C, and −10°C). Prewetting reduced the initial waiting time (the time it takes before the particles started to penetrate) by a few minutes at −10°C, but at higher temperatures, this reduction was insignificant. The particles penetrated the ice at a constant rate. At −10°C, the particles penetrated at 10–15 mm/hour, while at −2°C this speed is about five times higher. Prewetting does not seem to have a clear beneficial effect on the penetration rate. Suggestions are given on how to capture the results from this study into operational guidelines for deicing operations at airports, using sodium formate as deicer.

Effect of temperature on behaviour of red clay–structure interface

2019 ◽  
Vol 56 (1) ◽  
pp. 126-134 ◽  
Author(s):  
Chunhong Li ◽  
Gangqiang Kong ◽  
Hanlong Liu ◽  
Hossam Abuel-Naga
Keyword(s):  
Temperature Effect ◽  
Conceptual Understanding ◽  
Friction Angle ◽  
Effect Of Temperature ◽  
Experimental Program ◽  
Test Results ◽  
Shear Strength Parameters ◽  
Red Clay ◽  
Strain Behaviour ◽  
Different Temperatures

This study presents the results of an experimental investigation conducted to assess the temperature effects on shear stress–strain behaviour and shear strength parameters of red clay and its interface with the geostructure under different normal stresses (50, 100, 200, and 400 kPa). A modified direct shear test apparatus, capable of handling temperatures up to 50 °C, was used in this study. The experimental program includes shearing the red clay and red clay–structure interface at different temperatures (2, 15, 38 °C) and after subjecting it to different heating–cooling cycles. The test results in this study and the previous studies in the literature indicated that the temperature has insignificant effects on the friction angle of clay and clay–structure interface. However, the temperature effect on the cohesion of clay and the adhesion between the clay and structure depends on the normal stress level and history. A new conceptual understanding for the possible temperature effect on the clay–structure interface was introduced in this study and it was used to interpret the different interface test results in the literature.

scholarly journals The Respiration of some Planktonic copepods II. The Effect Of Temperature

1953 ◽  
Vol 31 (3) ◽  
pp. 447-460 ◽  
Author(s):  
D. T. Gauld ◽  
J. E. G. Raymont
Keyword(s):  
Respiratory Rate ◽  
The Body ◽  
The Other ◽  
Effect Of Temperature ◽  
Acartia Clausi ◽  
Temora Longicornis ◽  
Different Temperatures ◽  
Planktonic Copepods ◽  
The Difference ◽  
The Relationship

The respiratory rates of three species of planktonic copepods, Acartia clausi, Centropages hamatus and Temora longicornis, were measured at four different temperatures.The relationship between respiratory rate and temperature was found to be similar to that previously found for Calanus, although the slope of the curves differed in the different species.The observations on Centropages at 13 and 170 C. can be divided into two groups and it is suggested that the differences are due to the use of copepods from two different generations.The relationship between the respiratory rates and lengths of Acartia and Centropages agreed very well with that previously found for other species. That for Temora was rather different: the difference is probably due to the distinct difference in the shape of the body of Temora from those of the other species.The application of these measurements to estimates of the food requirements of the copepods is discussed.

scholarly journals Effect of temperature, CO2 and O2 on motility and mobility of Anisakidae larvae

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aiyan Guan ◽  
Inge Van Damme ◽  
Frank Devlieghere ◽  
Sarah Gabriël
Keyword(s):  
Enzymatic Digestion ◽  
Infected Fish ◽  
Effect Of Temperature ◽  
Video Recordings ◽  
Different Temperatures ◽  
Semi Solid ◽  
Zoonotic Parasites ◽  
The Impact ◽  
Phosphate Buffered Saline

AbstractAnisakidae, marine nematodes, are underrecognized fish-borne zoonotic parasites. Studies on factors that could trigger parasites to actively migrate out of the fish are very limited. The objective of this study was to assess the impact of different environmental conditions (temperature, CO2 and O2) on larval motility (in situ movement) and mobility (migration) in vitro. Larvae were collected by candling or enzymatic digestion from infected fish, identified morphologically and confirmed molecularly. Individual larvae were transferred to a semi-solid Phosphate Buffered Saline agar, and subjected to different temperatures (6 ℃, 12 ℃, 22 ℃, 37 ℃) at air conditions. Moreover, different combinations of CO2 and O2 with N2 as filler were tested, at both 6 °C and 12 °C. Video recordings of larvae were translated into scores for larval motility and mobility. Results showed that temperature had significant influence on larval movements, with the highest motility and mobility observed at 22 ℃ for Anisakis spp. larvae and 37 ℃ for Pseudoterranova spp. larvae. During the first 10 min, the median migration of Anisakis spp. larvae was 10 cm at 22 ℃, and the median migration of Pseudoterranova spp. larvae was 3 cm at 37 ℃. Larval mobility was not significantly different under the different CO2 or O2 conditions at 6 °C and 12 ℃. It was concluded that temperature significantly facilitated larval movement with the optimum temperature being different for Anisakis spp. and Pseudoterranova spp., while CO2 and O2 did not on the short term. This should be further validated in parasite-infected/spiked fish fillets.

scholarly journals Effect of Temperature during Drying and Storage of Dried Figs on Growth, Gene Expression and Aflatoxin Production

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 134
Author(s):  
Ana Isabel Galván ◽  
Alicia Rodríguez ◽  
Alberto Martín ◽  
Manuel Joaquín Serradilla ◽  
Ana Martínez-Dorado ◽  
...  
Keyword(s):  
Gene Expression ◽  
Aflatoxin Production ◽  
Effect Of Temperature ◽  
Mycotoxin Production ◽  
Industrial Processing ◽  
Factors Associated ◽  
Different Temperatures ◽  
Major Producer ◽  
Main Factors ◽  
And Storage

Dried fig is susceptible to infection by Aspergillus flavus, the major producer of the carcinogenic mycotoxins. This fruit may be contaminated by the fungus throughout the entire chain production, especially during natural sun-drying, post-harvest, industrial processing, storage, and fruit retailing. Correct management of such critical stages is necessary to prevent mould growth and mycotoxin accumulation, with temperature being one of the main factors associated with these problems. The effect of different temperatures (5, 16, 25, 30, and 37 °C) related to dried-fig processing on growth, one of the regulatory genes of aflatoxin pathway (aflR) and mycotoxin production by A. flavus, was assessed. Firstly, growth and aflatoxin production of 11 A. flavus strains were checked before selecting two strains (M30 and M144) for in-depth studies. Findings showed that there were enormous differences in aflatoxin amounts and related-gene expression between the two selected strains. Based on the results, mild temperatures, and changes in temperature during drying and storage of dried figs should be avoided. Drying should be conducted at temperatures >30 °C and close to 37 °C, while industry processing, storage, and retailing of dried figs are advisable to perform at refrigeration temperatures (<10 °C) to avoid mycotoxin production.

scholarly journals Corrosion Behaviour of 316L Stainless Steel in CNTs–Water Nanofluid: Effect of Temperature

Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 119
Author(s):  
Dana H. Abdeen ◽  
Muataz A. Atieh ◽  
Belabbes Merzougui
Keyword(s):  
Stainless Steel ◽  
316L Stainless Steel ◽  
Corrosion Behaviour ◽  
Gum Arabic ◽  
Steel Sample ◽  
Open Circuit ◽  
Deionized Water ◽  
Effect Of Temperature ◽  
Different Temperatures ◽  
In Series

The inhibition behavior of carbon nanotubes (CNTs) and Gum Arabic (GA) on the corrosion of 316L stainless steel in CNTs–water nanofluid under the effect of different temperatures was investigated by electrochemical methods and surface analysis techniques. Thereby, 316L stainless steel samples were exposed to CNTs–water nanofluid under temperatures of 22, 40, 60 and 80 °C. Two concentrations of the CNTs (0.1 and 1.0 wt.% CNTs) were homogenously dispersed in deionized water using the surfactant GA and tested using three corrosion tests conducted in series: open circuit test, polarization resistance test, and potentiodynamic scans. These tests were also conducted on the same steel but in solutions of GA-deionized water only. Tests revealed that corrosion increases with temperature and concentration of the CNTs–water nanofluids, having the highest corrosion rate of 32.66 milli-mpy (milli-mil per year) for the 1.0 wt.% CNT nanofluid at 80 °C. In addition, SEM observations showed pits formation around areas of accumulated CNTs that added extra roughness to the steel sample. The activation energy analysis and optical surface observations have revealed that CNTs can desorb at higher temperatures, which makes the surface more vulnerable to corrosion attack.

Effect of temperature on composite films made with activated carbon, graphite, or graphene oxide (GO) in a gelatin matrix

BioResources ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 77-95
Author(s):  
Siqiao Yang ◽  
Haichao Li
Keyword(s):  
Contact Angle ◽  
Activated Carbon ◽  
Water Absorption ◽  
Composite Films ◽  
Effect Of Temperature ◽  
Gelatin Matrix ◽  
Vapour Permeability ◽  
Blending Method ◽  
The Matrix ◽  
Different Temperatures

Activated carbon, graphite, and GO/gelatin composite films were prepared by the blending method. The properties of composites were characterized by tensile strength (TS), elongation at break (EB), water vapour permeability (WVP), water-absorption ability, contact angle, scanning electron microscopy (SEM), and moisture at different temperatures. The properties of GO/gelatin composite films were better when each of three kinds of carbon materials were used as reinforcement phases and added into the matrix gelatin. The results showed that EB and TS of GO/gelatin composite films were both excellent. The moisture of GO/gelatin composite films was greater than the others. SEM micrographs showed that GO had better compatibility and dispersibility with gelatin than activated carbon and graphite. The water absorption of GO/gelatin composite films were low, at 15 °C and 25 °C, and the WVP was low at 35 °C. The WVP of GO/gelatin composite films was lower than the others at different temperatures. The contact angle of GO/gelatin composite films was larger than the others.

scholarly journals CORROSION OF GALVANIZED STEEL AND ALUMINUM ALLOYS IN THE INDUSTRIAL ENVIRONMENT OF CHAMPIGNON

2019 ◽  
Vol 4 (5) ◽  
pp. 50-55
Author(s):  
С. Иконников ◽  
S. Ikonnikov ◽  
А. Блажнов ◽  
A. Blazhnov
Keyword(s):  
Aluminum Alloys ◽  
Penetration Rate ◽  
Galvanized Steel ◽  
Layer By Layer ◽  
Test Results ◽  
Structural Scheme ◽  
Construction Design ◽  
Alloys Of The Al ◽  
Rational Type ◽  
Selection Of

Generalization the experience building for the cultivation of champignons shows the diversity of construction solutions. The method of layer-by-layer assembly with galvanized steel and aluminum alloy coverings is economically feasible to use in champignons of frame structural scheme, enclosing structures of industrial premises. However, the technologically required wet air conditions of the premises and aggressive gases during construction design complicate the selection of a rational type of outer layers of enclosing structures. To reveal the rational material of coverings in the production premises of champignons, corrosion tests are carried out on samples of aluminum alloys of the Al-Mg, Al-Mn, Al-Mg-Si systems, technical aluminum, galvanized steel and galvanized steel with a protective coating. The type and corrosion penetration rate are set for the exposed samples. According to the test results, suitable covering materials for various types of champignon production premises are determined

scholarly journals The Effect of Probe Geometry on Rind Puncture Resistance Testing of Maize Stalks

2020 ◽  
Author(s):  
Douglas D. Cook ◽  
Kyler Meehan ◽  
Levan Asatiani ◽  
Daniel J Robertson
Keyword(s):  
Meta Analysis ◽  
Resistance Testing ◽  
Test Results ◽  
Lodging Resistance ◽  
Puncture Resistance ◽  
Analysis Of Results ◽  
Stalk Lodging ◽  
Penetration Tests ◽  
Shape And Size ◽  
Probe Geometry

Abstract Background: Stalk lodging (breaking of plant stems prior to harvest) is a major impediment to increasing agricultural yields of grain crops. Rind puncture resistance is commonly used to predict the lodging resistance of several crop species. However, there exist no standard operating procedures or suggested protocols for conducting rind penetration experiments. In addition, experimental details of rind penetration tests such as the shape and size of the penetrating probe are rarely reported in the literature. This has prevented meta-analysis of results and has likewise prevented key findings of past studies from being replicated. As a first step towards establishing an agreed upon measurement standard for rind puncture resistance this study investigates the effect of the puncturing probe’s geometry on test results.Results: Results demonstrate that probe geometry has a significant impact on test results. In particular, results showed that a 2mm diameter chamfered probe produced stronger correlations with stalk bending strength than a 1.5mm diameter pointed probe. The chamfered probe was also more strongly correlated with geometric features of the stalk that are known to influence stalk lodging resistance (e.g., rind thickness, diameter and section modulus). In addition, several alternative rind penetration metrics were investigated, and some were found to be superior to the most common rind penetration metric of maximum load. Conclusions:There is a need in the agricultural and plant science community to create agreed-upon operating procedures and testing standards related to mechanical traits of plant stems. In particular, a standardized probe geometry and insertion rate for rind penetration studies are needed to enable greater interoperability and meta-analysis of results. Probe shape and size should be reported in any study conducting rind penetration tests as these factors significantly impact test results.

scholarly journals Effect of Temperature on the Tribological Properties of Selected Thermoplastic Materials Cooperating with Aluminium Alloy

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7318
Author(s):  
Anita Ptak ◽  
Paula Taciak ◽  
Wojciech Wieleba
Keyword(s):  
Aluminium Alloy ◽  
Contact Pressure ◽  
Tribological Properties ◽  
Polymer Materials ◽  
Effect Of Temperature ◽  
Test Results ◽  
Friction Process ◽  
Before And After ◽  
Pin On Disc ◽  
Two Parameters

This article concerns the tribological properties of three selected polymer materials: polyamide PA6, polyethylene PE-HD and polyetheretherketone composite PEEK/BG during sliding against aluminium alloy EN AW-2017A in the presence of hydraulic oil HLP 68. The tests were carried out under contact pressure p of 3.5–11 MPa at ambient temperature T ranging from −20 °C to +20 °C. The dependence of kinetic friction coefficient μk on the two parameters was determined through tribological tests carried out using a pin-on-disc tribometer. A five-level central composite rotatable design (CCRD) was adopted for the experiment. All the test results were statistically analysed. The microhardness of the surface of the polymeric material was measured before and after the friction process. The surface was also examined under SEM. Temperature and contact pressure have been found to have a significant effect on the tribological properties of the tested sliding pairs. Relative to the applied friction conditions, the surfaces after friction showed rather heavy signs of wear.

scholarly journals MECHANICAL CHARACTERIZATION OF PA 12 AND HDPE PIPES BEFORE AND AFTER AGING IN WATER AT TWO DIFFERENT TEMPERATURES

2021 ◽  
Vol 9 (1) ◽  
pp. 248-256
Author(s):  
J.A. dos Santos ◽  
R.C. Tucunduva ◽  
J.R.M. D’Almeida
Keyword(s):  
High Density Polyethylene ◽  
Mechanical Performance ◽  
High Density ◽  
Effect Of Temperature ◽  
Polyamide 12 ◽  
Polyethylene Pipes ◽  
Before And After ◽  
Different Temperatures ◽  
Deterioration Process ◽  
Combined Action

Polymer pipes are being widely used by many industrial segments. Although not affected by corrosion, the mechanical performance of these pipes can be reduced due to exposure to temperature, UV radiation and by contact with various fluids. Depending on the deterioration process, embrittlement or plasticization may occur, and the service life of the pipe can be severely reduced. In this work, the combined action of temperature and water upon the mechanical performance of polyamide 12 and high-density polyethylene pipes is evaluated. Destructive and non-destructive techniques were used and the performance of both materials was compared. Both polymers were platicized by the effect of water. However, for high density polyethylene the effect of temperature was more relevant than for polyamide. This behavior was attributed to the dependence of the free volume with the markedly different glass transition temperature of the polymers and the temperatures of testing.

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