Effect of UV radiation and temperature on rheological features of multi-layer agricultural packaging foils

2008 ◽  
Vol 4 (1) ◽  
pp. 27-44 ◽  
Author(s):  
Attila Csatár ◽  
László Fenyvesi
Keyword(s):  
Uv Radiation ◽  
Environmental Temperature ◽  
Weather Conditions ◽  
Close Correlation ◽  
Relaxation Curve ◽  
Cold Weather ◽  
Transmission Properties ◽  
Warm Weather ◽  
Measured Relaxation ◽  
Maximum Transmission

The objective of the work reported here was to determine the influence of UV radiation and environmental temperature on the strength and rheological characteristics of multilayer agricultural packaging foils. The transmission properties of the experimental foils were tested in 286–363.5 nm range. The analysis of transmission properties of the foils showed that the maximum transmission was 10 % and 45 % with the experimental violet foils having 20 % and 5 % UV inhibitor in them, respectively. However, the transmission was higher than 80 % with the white foils of 5 % and 20 % inhibitor.The effect of the temperature on the tensile stress of commercial foils was investigated gated in the −20 ≤ T ≤ 50 °C temperature range. The measured relaxation curve was found to have a close correlation both for −10°C and 45°C with the calculated results. The highest reduced strength decreased as the function of the temperature according to the σ= −0,1861 T +19,107 [MPa] equation. Therefore, the probability of the break of the foils in cold weather is definitely higher than under warm weather conditions.

The Relationship Between Self-Regulatory Efficacy and Physical Activity in Adolescents With a Caveat: A Cross-Lag Design Examining Weather

2020 ◽  
Vol 32 (4) ◽  
pp. 210-216
Author(s):  
Kathleen S. Wilson ◽  
Kevin S. Spink
Keyword(s):  
Physical Activity ◽  
Self Efficacy ◽  
Structural Equation ◽  
Weather Conditions ◽  
Cold Weather ◽  
Equation Modeling ◽  
Future Research ◽  
School Year ◽  
Warm Weather ◽  
The Relationship

Purpose: The use of self-efficacy to predict physical activity has a long history. However, this relationship is complex, as self-efficacy is thought to influence and be influenced by physical activity. The directionality of the self-regulatory efficacy (SRE) and physical activity relationship was examined using a cross-lagged design. A secondary purpose was to examine these relationships across differing weather conditions. Methods: Canadian adolescents (N = 337; aged between 13 and 18 years) completed the physical activity and SRE measures 4 times during a school year. Structural equation modeling was used to perform a cross-lag analysis. Results: The relationships between physical activity and SRE appeared to be weather dependent. During a more challenging weather period (eg, cold weather), the relationship between physical activity and SRE was bidirectional. However, no relationship emerged when the 2 constructs were assessed during a more optimal weather period (eg, warm weather). Conclusions: Some support has been provided for the bidirectional nature of the relationship between physical activity and SRE. The relationship appeared to be qualified by climate considerations, suggesting that future research examine how weather may relate not just to physical activity but also to the correlates of physical activity.

N2O emissions from secondary clarifiers and their contribution to the total emissions of the WWTP

2014 ◽  
Vol 70 (4) ◽  
pp. 720-728 ◽  
Author(s):  
Anna Mikola ◽  
Mari Heinonen ◽  
Heta Kosonen ◽  
Maarit Leppänen ◽  
Pirjo Rantanen ◽  
...  
Keyword(s):  
Wastewater Treatment Plants ◽  
Weather Conditions ◽  
Cold Weather ◽  
N2o Emissions ◽  
Warm Weather ◽  
Nitrification Process ◽  
Term Variation ◽  
Online Measurements ◽  
June July

Recent studies have indicated that the emissions of nitrous oxide, N2O, constitute a major part of the carbon footprint of wastewater treatment plants (WWTPs). Denitrification occurring in the secondary clarifier basins has been observed by many researchers, but until now N2O emissions from secondary clarifiers have not been widely reported. The objective of this study was to measure the N2O emissions from secondary clarifiers and weigh the portion they could represent of the overall emissions at WWTPs. Online measurements over several days were carried out at four different municipal WWTPs in Finland in cold weather conditions (March) and in warm weather conditions (June–July). An attempt was made to define the conditions in which N2O emissions from secondary clarifiers may occur. It was evidenced that large amounts of N2O can be emitted from the secondary clarifiers, and that the emissions have long-term variation. It was assumed that part of the N2O released in secondary clarification was originally formed in the activated sludge basin. The emissions from secondary clarification thus seem to be dependent on conditions of the nitrification and denitrification accomplished in the denitrification–nitrification process and on the amount of sludge stored in the secondary clarifiers.

scholarly journals Sweat rate and environmental factors in junior Laser class sailors

2020 ◽  
Vol 37 (5) ◽  
pp. 298-304
Author(s):  
GJ Lorenzo González ◽  
J Toro Prieto-Puga ◽  
T Teresa Seoane Pillado ◽  
E Fernández Windscheid
Keyword(s):  
Food Intake ◽  
Environmental Factors ◽  
Body Mass ◽  
Environmental Temperature ◽  
Sweat Rate ◽  
Weather Conditions ◽  
Fluid Replacement ◽  
Cold Weather ◽  
Body Mass Change ◽  
Target Weight

Introduction: Recent studies have reported differences in sweat rate (SR) in laser class (LC) sailors under extreme environmental conditions (EC). This study aimed to determine a ‘standard-like’ SR in junior Laser 4.7 sailors under ‘not-extreme’ weather conditions to achieve an adequate fluid replacement rate for training and racing sessions. Additionally, we analysed the hypothetical relationship between SR and certain environmental factors, not just considering them as independent variables, but also including them as a whole factor, usually known as ‘windchill’ (WCh). Material and method: Nine male elite junior Laser 4.7 class athletes were included in this descriptive study. They were monitored during the entire year of training and racing sessions, including national and international championships. Body mass changes as well as their food and fluid intake were measured for each sailor before and after sailing to estimate SR, absolute body mass change, and percentage body mass variation for all the sessions. Athletes were asked to maintain “ab libitum” fluid and food intake during the study. Environmental temperature, wind speed, and relative humidity were measured. Results: Significant differences (p = 0.012) were observed between training and racing sessions with respect to SR, 0.18 (±0.14) L.h−1 vs. 0.23 (± 0.12 L.h−1). Environmental temperature and WCh during racing showed an inverse relationship with SR. Discussion: This result suggests that increased fluid and food intake are required under cold weather conditions to maintain the ‘target’ weight during the competitions and improve performance.

Vulnerability of sweet cherry cultivars to continuous periods of spring frosts in Plovdiv, Bulgaria

2020 ◽  
Vol 12 (4) ◽  
pp. 348-352
Author(s):  
S. Malchev ◽  
S. Savchovska
Keyword(s):  
Sweet Cherry ◽  
Weather Conditions ◽  
Frost Damage ◽  
Cold Weather ◽  
Bud Burst ◽  
Intermediate Group ◽  
Air Temperatures ◽  
Wide Range ◽  
Group Form ◽  
Sweet Cherry Cultivars

Abstract. The periods with continuous freezing air temperatures reported during the spring of 2020 (13 incidents) affected a wide range of local and introduced sweet cherry cultivars in the region of Plovdiv. They vary from -0.6°C on March 02 to -4.9°C on March 16-17. The duration of influence of the lowest temperatures is 6 and 12 hours between March 16 and 17. The inspection of fruit buds and flowers was conducted twice (on March 26 and April 08) at different phenological stages after continuous waves of cold weather conditions alternated with high temperatures. During the phenological phase ‘bud burst’ (tight cluster or BBCH 55) some of the flowers in the buds did not develop further making the damage hardly detectable. The most damaged are hybrid El.28-21 (95.00%), ‘Van’ (91.89%) and ‘Bing’ (89.41%) and from the next group ‘Lapins’ (85.98%) and ‘Rosita’ (83.33%). A larger intermediate group form ‘Kossara’ (81.67%), ‘Rozalina’ (76.00%), ‘Sunburst’ (75.00%), ‘Bigarreau Burlat’ (69.11%) and ‘Kuklenska belitza’ (66.67%). Candidate-cultivar El.17-90 ‘Asparuh’ has the lowest frost damage values of 55.00% and El.17-37 ‘Tzvetina’ with damage of 50.60%.

Heating up trickling filters to tackle cold weather conditions

2000 ◽  
Vol 41 (1) ◽  
pp. 163-166 ◽  
Author(s):  
W. Gebert ◽  
P.A. Wilderer
Keyword(s):  
Waste Heat ◽  
Treatment Plant ◽  
Weather Conditions ◽  
Pilot Scale ◽  
Cold Weather ◽  
Filling Material ◽  
Trickling Filter ◽  
Biofilm Thickness ◽  
Trickling Filters ◽  
Biofilm Support

The investigated effects of heating the filling material in trickling filters were carried out at the Ingolstadt wastewater treatment plant, Germany. Two pilot scale trickling filters were set up. Heat exchanger pipings were embedded in the filter media of one of these trickling filters, and the temperature in the trickling filter was raised. The other trickling filter was operated under normal temperature conditions, and was used as a control. The results clearly demonstrate that the performance of trickling filters cannot be constantly improved by heating the biofilm support media. A sustained increase of the metabolic rates did not occur. The decrease of the solubility of oxgen in water and mass transfer limitations caused by an increase of the biofilm thickness are the main reasons for that. Thus, the heating of trickling filters (e.g. by waste heat utilization) in order to increase the capacity of trickling filters under cold weather conditions cannot be recommended.

scholarly journals Cold weather is a predisposing factor for testicular torsion in a tropical country. A retrospective study

2014 ◽  
Vol 133 (3) ◽  
pp. 187-190 ◽  
Author(s):  
Daniel de Oliveira Gomes ◽  
Rafael Rocha Vidal ◽  
Bruno Figueiredo Foeppel ◽  
Danilo Fiorindo Faria ◽  
Minori Saito
Keyword(s):  
Retrospective Study ◽  
Symptom Onset ◽  
Testicular Torsion ◽  
Weather Conditions ◽  
Cold Weather ◽  
Predisposing Factor ◽  
Tropical Country ◽  
Etiologic Role ◽  
Urological Emergency

CONTEXT AND OBJECTIVE:Testicular torsion is a medical and urological emergency because it can lead to loss of the organ. The theory of seasonal testicular torsion occurrence is based on studies from institutions located in cold and temperate regions. The objective here was to determine whether cold weather is associated with higher incidence of testicular torsion in a tropical country, such as Brazil.DESIGN AND SETTING:Retrospective study, conducted in a tertiary and teaching hospital.METHODS:Patients with acute testicular torsion confirmed by surgery between April 2006 and March 2011 were studied. Information on weather conditions at the time of symptom onset was collected.RESULTS:A total of 64 testicular torsion cases were identified. The months with the highest incidences of testicular torsion were June (16%), July (19%) and August (11%), which had the lowest mean temperatures, of 17.6 °C, 16.4 °C and 18.2 °C, respectively. Eleven percent of cases occurred during spring (October to December), 16% occurred in summer (January to March), 34% occurred in fall (April to June) and 39% occurred in winter (July to September). There was a significant association between the incidence of testicular torsion and the season (fall and winter), P < 0.001.CONCLUSIONS:Testicular torsion follows a seasonal association even in a tropical country, and is more frequent in the colder months of the year, namely fall and winter, when almost three-quarters of the cases occurred. These observations add further evidence that cold weather has an etiologic role in testicular torsion occurrence.

scholarly journals Epidemiology of Equestrian Accidents: a Literature Review

2019 ◽  
Author(s):  
Lauren Meredith ◽  
Robert Ekman ◽  
Karin Brolin
Keyword(s):  
Literature Review ◽  
Soft Tissue Injuries ◽  
Weather Conditions ◽  
Review Of The Literature ◽  
Hospital Data ◽  
Young Females ◽  
Body Regions ◽  
Horse Riding ◽  
Warm Weather ◽  
The Usa

Purpose: This manuscript aimed to present a review of the literature pertaining to horse riding and other horse-related injuries. Method: A review of the literature was performed, searching for appropriate terms with regards to horse accidents, horse riding injuries and protective clothing for the horse riding context. The literature review search returned 151 relevant full-text articles, with 71 of these detailing the overall injury epidemiology of horse-related accidents. Most of these studies were conducted in the USA and used a retrospective review of hospital data methodology. Results: Of the 71 articles investigated, 60 suggested that those most frequently involved in horse-related accidents are young females and 97% of papers investigating injury mechanisms found the most commonly involved was a fall from horseback. It was suggested in multiple studies that these injury events mostly occurred in warm weather conditions, when the horse behaved in an unexpected manner. Injury type and location varied by the primary mechanism of injury; but frequently involved body regions were the head and upper extremities, and the most common injuries observed were fractures and soft tissue injuries. Neurological trauma was reported by all relevant studies to be the most frequent cause of fatality. Conclusion: Some improvements in horse-related accident numbers and outcomes have been observed with the development and introduction of protective devices such as helmets and vests. Yet despite the benefits of helmet and vest usage, there is evidence to suggest helmets do not perform as well as they could. Further work could investigate improvements in safety measures and risk factors associated with fatalities.

scholarly journals Ice fog monitoring near Fairbanks, AK

2021 ◽  
Author(s):  
Dragos Vas ◽  
Steven Peckham ◽  
Carl Schmitt ◽  
Martin Stuefer ◽  
Ross Burgener ◽  
...  
Keyword(s):  
Power Generation ◽  
Environmental Conditions ◽  
Weather Conditions ◽  
Cold Weather ◽  
The Arctic ◽  
Local Power ◽  
Environmental Complexity ◽  
Ice Fog ◽  
Innovative Methods ◽  
Generation Facility

Ice fog events, which occur during the Arctic winter, result in greatly decreased visibility and can lead to an increase of ice on roadways, aircraft, and airfields. The Fairbanks area is known for ice fog conditions, and previous studies have shown these events to be associated with moisture released from local power generation. Despite the identified originating mechanism of ice fog, there remains a need to quantify the environmental conditions controlling its origination, intensity, and spatial extent. This investigation focused on developing innovative methods of identifying and characterizing the environmental conditions that lead to ice fog formation near Fort Wainwright, Alaska. Preliminary data collected from December 2019 to March 2020 suggest that ice fog events occurred with temperatures below −34°C, up to 74% of the time ice fog emanated from the power generation facility, and at least 95% of ice particles during ice fog events were solid droxtals with diameters ranging from 7 to 50 μm. This report documents the need for frequent and detailed observations of the meteorological conditions in combination with photographic and ice particle observations. Datasets from these observations capture the environmental complexity and the impacts from energy generation in extremely cold weather conditions.

scholarly journals Reclaiming land flooded with salt water.

1953 ◽  
Vol 1 (4) ◽  
pp. 225-244
Author(s):  
C.W.C. Beekom
Keyword(s):  
Salt Concentration ◽  
Sea Water ◽  
Salt Water ◽  
Soil Layer ◽  
Weather Conditions ◽  
Phleum Pratense ◽  
Active Growth ◽  
Warm Weather ◽  
Different Types ◽  
Spring Sowing

The effect of sea floods on grassland is described and recommendations are made for the restoration of inundated grassland. Turf may be heavily damaged after +or- 4 weeks inundation with water containing more than 20 g. NaCl per 1. At lower salt concentrations Poa sp. and Trifolium repens are still badly damaged but other species, notably Lolium perenne, Agrostis stolonifera and Alopecurus sp., are capable of immediate regrowth after drainage. If grassland remains submerged during spring, rising temperatures promote active growth of the grasses followed by rapid decay caused by lack of oxygen. L. perenne is especially sensitive to submergence in warm weather. The dominant weed communities which appear on land on which the turf has been destroyed by sea-water are described. Reseeding is recommended as the quickest method of restoring badly damaged turf. The flooded land should first be thoroughly drained and then repeatedly harrowed to produce a shallow seed-bed on which herbage mixtures can be sown without the application of gypsum. Given average weather conditions, normal permanent grassland mixtures can be sown at salt concentrations, measured in spring, of up to 8-10 g. NaCl per 1. of moisture in the 5-20 cm. soil layer. At a salt concentration of about 10 g. per 1. measured in spring, L. perenne tends to dominate over other species while Poa sp. and T. repens suffer during the summer. At a salt concentration of 10-15 g. per 1. in spring, Poa sp. and T. repens should be omitted from seed mixtures, instead mixtures consisting of different types of L. perenne, Festuca pratensis and Phleum pratense should be sown. When the salt concentration of the soil moisture is higher that 15 g. per 1. in spring, sowing should be delayed and the weeds checked by mowing or grazing. Temporary rises of the salt concentration in dry symmers to 25 g. per 1. are tolerated by L. perenne, F. pratensis and Ph. pratense; similar rises up to 15-18 g. per 1. are tolerated by Poa sp. and T. repens.-W.J.B. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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