scholarly journals Apple Sunburn Risk Detection—A Simple Model for Agricultural Decision Making and Some Fruit Temperature Measurements

2021 ◽  
Vol 63 (1) ◽  
pp. 25-36
Author(s):  
Klaus-Peter Wittich

AbstractAs a response to strong radiative heating, the fruit temperature of apples may rise significantly above the air temperature. This may result in damage to the skin tissue and the epidermal and hypodermal cell layers. To avoid economic losses induced by sunburn symptoms on the skin, apple growers need forecasts of the fruit temperature, which will allow them to organize sun-protection measures in time.The temperatures of detached apples, which had been exposed to incident radiation and wind, were measured in order to quantify the extent of fruit heating under the climate conditions of northern Germany. On average, the daily maximum skin temperatures measured on the sunlit south side of the fruit during selected sunny and warm days were about 7 °C above the daily maximum air temperature. However, skin temperatures of more than 40 °C (the predefined warning threshold) were rarely detected, indicating that sunburn is still an uncommon phenomenon in northern Germany. Maximum apple-core temperatures were on average 4 °C higher than the maximum temperatures of ambient air.Based on energy balance principles, a simple model has been developed to predict the diurnal cycle of the sky- and ground-facing hemispherical apple temperatures. Focusing on fruit growers’ needs, daily temperature maxima of the modeled sky-facing hemisphere were compared with skin temperatures measured on the sunlit south side, resulting in a mean absolute error (MAE) of 1.7 °C. Comparison between daily maxima of total sphere temperatures and apple core temperatures provided better correlations (MAE = 0.8 °C).

2013 ◽  
Vol 834-836 ◽  
pp. 1744-1748
Author(s):  
Salwa Tashkandi ◽  
Sinnappoo Kanesalingam ◽  
Li Jing Wang

The main objective of this research was to measure the thermal insulation using a thermal manikin dressed in various ensembles of clothing within the abaya. A range of clothing and abaya has been tested using a heated manikin. The thermal manikin experiments were conducted in dry condition. The ambient air temperature for the dry tests was set at 23oC and Relative Humidity at 50% and the mean skin temperatures averaged at 35oC. The results showed that the daily clothing and abaya affect the thermal insulation performance. It is uncomfortable to wear more layers of the daily wear clothing within the abaya. The abaya worn over the head thermally insulated slightly more than the abaya worn from the shoulder.


Author(s):  
Gonzalo Ossa ◽  
Thomas M. Lilley ◽  
Austin G. Waag ◽  
Melissa B. Meierhofer ◽  
Joseph S. Johnson

ABSTRACTThere are few studies of day-roosting ecology of bats inhabiting the southernmost forests of South America, where cool summer temperatures and land management practices pose several challenges. The goal of the present study was to describe day-roosting habitats and patterns of thermoregulation in two bat species occurring on Tierra del Fuego, Myotis chiloensis (Chilean myotis) and Histiotus magellanicus (southern big-eared brown bat), during late spring. To do so, we tagged 17 bats with temperature-sensitive radio-transmitters, located 17 day-roosts, and collected 81 days of skin temperature data. We concurrently recorded ambient air temperature to determine its effect on torpor use. Both species were found roosting in large diameter (77.8 ± 6 cm), typically live, Nothofagus pumilio trees (lenga) located on the edges of forest gaps or within stands primarily composed of smaller, younger trees. Bats of both species frequently used torpor, with skin temperatures dropping below a torpor threshold on 89% of days (n = 72) and daily minimum skin temperatures averaging 16.5 °C over the course of our study. Average daily air temperature was a significant predictor of torpor use, with lower skin temperatures and more time spent in torpor observed on colder days. Minimum skin temperature and time spent torpid did not vary between bat species, nor did the characteristics of day-roosts. These data show that spring temperatures in Tierra del Fuego pose an energetic challenge that bats meet through frequent use of torpor, and likely, habitat selection. We recommend local conservation efforts keep these thermal challenges in mind by retaining large trees, which may provide warmer microclimates or room for social groups.


1982 ◽  
Vol 17 (1) ◽  
pp. 135-148
Author(s):  
P.T. Wong ◽  
D.S. Mavinic

Abstract The treatability of a municipal leachate (BOD5 = 8090 mg/L) was investigated, by aerobic biostabilization, at a nutrient loading of BOD5:N:P of 100:3.2:1.1. The first stage effluents were subsequently polished by lime-magnesium coagulation. The ranges of ambient air temperature and sludge age studied were 5° to 25°C and 5 to 20 days, respectively. In the biostabilization phase, a BOD5:N:P loading of 100:3.2:1.1 was found to be “adequate” for treatment. Organic and metal removals in the first stage units were excellent. Under all conditions investigated, except for the two units close to washout conditions (5-day sludge age units at 5° and 10°C), BOD5 and COD removals of at least 99.4 and 96.4 percent, respectively, were achieved. Similarly, removal rates for most of the metals monitored were greater than 90 percent. In general, the removal of residual contaminants was not enhanced significantly by the addition of magnesium in the lime-magnesium polishing step.


2020 ◽  
Vol 35 (4) ◽  
pp. 379-399
Author(s):  
Seyed M. Karimi ◽  
Ali Maziyaki ◽  
Samaneh Ahmadian Moghadam ◽  
Mahtab Jafarkhani ◽  
Hamid Zarei ◽  
...  

AbstractStudies that assess the connection between the prevalence of chronic diseases and continuous exposure to air pollution are scarce in developing countries, mainly due to data limitations. Largely overcoming data limitations, this study aimed to investigate the association between the likelihood of reporting a set of chronic diseases (diabetes, cancer, stroke and myocardial infarction, asthma, and hypertension) and continuous exposure to carbon monoxide (CO), nitrogen dioxide (NO2), ozone (O3), and coarse particulate matter (PM10). Using the estimated associations, the disease burden and economic costs of continuous exposure to air pollutants were also approximated. A 2011 Health Equity Assessment and Response Tool survey from Tehran, Iran, was used in the main analyses. A sample of 67,049 individuals who had not changed their place of residence for at least 2 years before the survey and reported all relevant socioeconomic information was selected. The individuals were assigned with the average monthly air pollutant levels of the nearest of 16 air quality monitors during the 2 years leading to the survey. Both single- and multi-pollutant analyses were conducted. The country’s annual household surveys from 2002 to 2011 were used to calculate the associated economic losses. The single-pollutant analysis showed that a one-unit increase in monthly CO (ppm), NO2 (ppb), O3 (ppb), and PM10 (μg/m3) during the 2 years was associated with 751 [confidence interval (CI): 512–990], 18 (CI: 12–24), 46 (CI: −27–120), and 24 (CI: 13–35) more reported chronic diseases in 100,000, respectively. The disease-specific analyses showed that a unit change in average monthly CO was associated with 329, 321, 232, and 129 more reported cases of diabetes, hypertension, stroke and myocardial infarction, and asthma in 100,000, respectively. The measured associations were greater in samples with older individuals. Also, a unit change in average monthly O3 was associated with 21 (in 100,000) more reported cases of asthma. The multi-pollutant analyses confirmed the results from single-pollutant analyses. The supplementary analyses showed that a one-unit decrease in monthly CO level could have been associated with about 208 (CI: 147–275) years of life gained or 15.195 (CI: 10.296–20.094) thousand US dollars (USD) in life-time labor market income gained per 100,000 30-plus-year-old Tehranis.


2021 ◽  
Vol 13 (12) ◽  
pp. 2355
Author(s):  
Linglin Zeng ◽  
Yuchao Hu ◽  
Rui Wang ◽  
Xiang Zhang ◽  
Guozhang Peng ◽  
...  

Air temperature (Ta) is a required input in a wide range of applications, e.g., agriculture. Land Surface Temperature (LST) products from Moderate Resolution Imaging Spectroradiometer (MODIS) are widely used to estimate Ta. Previous studies of these products in Ta estimation, however, were generally applied in small areas and with a small number of meteorological stations. This study designed both temporal and spatial experiments to estimate 8-day and daily maximum and minimum Ta (Tmax and Tmin) on three spatial scales: climate zone, continental and global scales from 2009 to 2018, using the Random Forest (RF) method based on MODIS LST products and other auxiliary data. Factors contributing to the relation between LST and Ta were determined based on physical models and equations. Temporal and spatial experiments were defined by the rules of dividing the training and validation datasets for the RF method, in which the stations selected in the training dataset were all included or not in the validation dataset. The RF model was first trained and validated on each spatial scale, respectively. On a global scale, model accuracy with a determination coefficient (R2) > 0.96 and root mean square error (RMSE) < 1.96 °C and R2 > 0.95 and RMSE < 2.55 °C was achieved for 8-day and daily Ta estimations, respectively, in both temporal and spatial experiments. Then the model was trained and cross-validated on each spatial scale. The results showed that the data size and station distribution of the study area were the main factors influencing the model performance at different spatial scales. Finally, the spatial patterns of the model performance and variable importance were analyzed. Both daytime and nighttime LST had a significant contribution in the 8-day Tmax estimation on all the three spatial scales; while their contribution in daily Tmax estimation varied over different continents or climate zones. This study was expected to improve our understanding of Ta estimation in terms of accuracy variations and influencing variables on different spatial and temporal scales. The future work mainly includes identifying underlying mechanisms of estimation errors and the uncertainty sources of Ta estimation from a local to a global scale.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3398
Author(s):  
Yi Long ◽  
Kun Liu ◽  
Yongli Zhang ◽  
Wenzhe Li

Inorganic cesium lead halide perovskites, as alternative light absorbers for organic–inorganic hybrid perovskite solar cells, have attracted more and more attention due to their superb thermal stability for photovoltaic applications. However, the humid air instability of CsPbI2Br perovskite solar cells (PSCs) hinders their further development. The optoelectronic properties of CsPbI2Br films are closely related to the quality of films, so preparing high-quality perovskite films is crucial for fabricating high-performance PSCs. For the first time, we demonstrate that the regulation of ambient temperature of the dry air in the glovebox is able to control the growth of CsPbI2Br crystals and further optimize the morphology of CsPbI2Br film. Through controlling the ambient air temperature assisted crystallization, high-quality CsPbI2Br films are obtained, with advantages such as larger crystalline grains, negligible crystal boundaries, absence of pinholes, lower defect density, and faster carrier mobility. Accordingly, the PSCs based on as-prepared CsPbI2Br film achieve a power conversion efficiency of 15.5% (the maximum stabilized power output of 15.02%). Moreover, the optimized CsPbI2Br films show excellent robustness against moisture and oxygen and maintain the photovoltaic dark phase after 3 h aging in an air atmosphere at room temperature and 35% relative humidity (R.H.). In comparison, the pristine films are completely converted to the yellow phase in 1.5 h.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Younes Bahammou ◽  
Mounir Kouhila ◽  
Haytem Moussaoui ◽  
Hamza Lamsyehe ◽  
Zakaria Tagnamas ◽  
...  

PurposeThis work aims to study the hydrothermal behavior of mortar cement toward certain environmental factors (ambient air temperature and air velocity) based on its drying kinetics data. The objective is to provide a better understanding and controlling the stability of mortar structures, which integrate the sorption phenomenon, drying process, air pressure and intrinsic characteristics. This leads to predict the comportment of mortar structures in relation with main environmental factors and minimize the risk of cracking mortar structures at an early age.Design/methodology/approachThermokinetic study was carried out in natural and forced convection solar drying at three temperatures 20, 30 and 40°C and three air velocities (1, 3 and 5 m.s-1). The empirical and semiempirical models tested successfully describe the drying kinetics of mortar. These models simulate the drying process of water absorbed by capillarity, which is the most common humidity transfer mechanism in building materials and contain parameters with physical significance, which integrate the effect of several environmental factors and intrinsic characteristics of mortar structures.FindingsThe models simulate the drying process of water absorbed by capillarity, which is the most common humidity transfer mechanism in building materials and contain parameters with physical significance, which integrate the effect of several environmental factors and intrinsic characteristics of mortar structures. The average activation energy obtained expressed the temperature effect on the mortar diffusivity. The drying constant and the diffusion coefficient can be used to predict the influence of these environmental factors on the drying behavior of various building materials and therefore on their durability.Originality/valueEvaluation of the effect of several environmental factors and intrinsic characteristics of mortar structures on their durability.


2021 ◽  
Author(s):  
Achim Drebs ◽  
Tim Sinsel ◽  
Kirsti Jylhä

&lt;p&gt;In our research we describe the micro-climatological influences of two heat-waves around and the air temperature development in a certain old people&amp;#8217;s home in Helsinki, Finland. The stand-alone six-storey concrete building was erected in the late 1970&amp;#8217;s and represents the prevailing construction type of this area. The building is located on a slightly southwards declining slope.&lt;/p&gt;&lt;p&gt;The first simulation used real meteorological forcing-data from the heat-wave event in summer 2018, which lasted from July, 13&lt;sup&gt;th&lt;/sup&gt; until August, 5&lt;sup&gt;th&lt;/sup&gt;. In this period the daily maximum air temperature reached almost every day 25 &amp;#176;C and more, sometimes even more than 30 &amp;#176;C. All air temperature, wind, humidity, and solar radiation (cloudiness) measurements were conducted at a near-by synoptical weather station.&lt;/p&gt;&lt;p&gt;The second simulation used fourteen-day constructed meteorological forcing-data, based on a clear-sky, slowly increasing air temperature, higher than normal humidity, and low wind conditions assumption starting on July, 13&lt;sup&gt;th&lt;/sup&gt; (day 194 of the year).&lt;/p&gt;&lt;p&gt;We used the holistic ENVI-met simulation soft-ware to simulate the physical environment around the old people&amp;#8217;s home and especially the energy fluxes inside the concrete walls to explain the needs for cooling demands.&lt;/p&gt;&lt;p&gt;The research is part of the HEATCLIM-project financed by the Academy of Finland Science Program CLIHE (2020-2023).&lt;/p&gt;


2013 ◽  
Vol 30 (8) ◽  
pp. 1757-1765 ◽  
Author(s):  
Sayed-Hossein Sadeghi ◽  
Troy R. Peters ◽  
Douglas R. Cobos ◽  
Henry W. Loescher ◽  
Colin S. Campbell

Abstract A simple analytical method was developed for directly calculating the thermodynamic wet-bulb temperature from air temperature and the vapor pressure (or relative humidity) at elevations up to 4500 m above MSL was developed. This methodology was based on the fact that the wet-bulb temperature can be closely approximated by a second-order polynomial in both the positive and negative ranges in ambient air temperature. The method in this study builds upon this understanding and provides results for the negative range of air temperatures (−17° to 0°C), so that the maximum observed error in this area is equal to or smaller than −0.17°C. For temperatures ≥0°C, wet-bulb temperature accuracy was ±0.65°C, and larger errors corresponded to very high temperatures (Ta ≥ 39°C) and/or very high or low relative humidities (5% &lt; RH &lt; 10% or RH &gt; 98%). The mean absolute error and the root-mean-square error were 0.15° and 0.2°C, respectively.


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