A small resistance thermometer psychrometer for use in high solar radiation conditions

Transferring seedlings of Eucalyptus lansdowneana from a heated glasshouse (24/19°C) to a cold glasshouse (15/10°C) for 5 or 10 weeks and back to the heated glasshouse was sufficient to induce floral buds. Bud production was further enhanced when seedlings were transferred to cold conditions during periods of high solar radiation. Under low levels of solar radiation and short duration of cold, 0-5 weeks, plants reverted to vegetative development, suggesting a low floral induction stimulus. Seedlings that produced a visible floral inflorescence had fewer leaves than seedlings grown under similar conditions that had not produced an inflorescence. This was more noticeable under high-radiation conditions. Plants grown under outside conditions in Canberra and transferred to a heated glasshouse (25/ 18°C) during winter initiated inflorescences 7-9 weeks earlier than plants grown continuously outside. The early initiation enabled buds to develop and flower before the onset of the following winter. More buds were initiated in plants transferred to the glasshouse in September compared with 16 June or 28 July. Plants transferred on 16 June initiated few buds or none at all. These plants may have been in a juvenile or transitional stage of development, experienced insufficient cold for full induction or been limited by the low winter irradiances. Floral response occurred under both long days (phytotron) and short days under outside conditions in Canberra, suggesting that E. lansdowneana may well be relatively insensitive to day length. These results are discussed in relation to controlled breeding programs which aim to manipulate flowering time and duration to decrease the generation interval.

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485 PB 125 QUANTIFYING THE EFFECT OF PLUG-FLAT COLOR ON SOIL SURFACETEMPERATURE

HortScience ◽

10.21273/hortsci.29.5.500g ◽

1994 ◽

Vol 29 (5) ◽

pp. 500g-501

Author(s):

James E. Faust ◽

Hiroshi Shimizu ◽

Royal D. Heins

Keyword(s):

Solar Radiation ◽

Surface Temperature ◽

Soil Temperature ◽

Soil Surface ◽

Image Analyzer ◽

Fine Wire ◽

High Solar Radiation ◽

White Sheet ◽

Soil Surface Temperature ◽

Radiation Conditions

Surface temperature of a soilless medium in white, gray, and black plug sheets was measured to determine the value of using plug sheets of different colors to control soil temperature during seed germination and young seedling growth. Plugs sheets were placed in a greenhouse set at 25°C. Soil surface temperatures were measured with fine-wire thermocouples inserted into the top 1 mm of the soil. A thermal image analyzer was used to determine the temperature variation across the plug flat. At night, soil temperature in all three colored flats was 3°C below air temperature because of evaporation and net longwave radiative losses to the greenhouse glass. Surface temperature of moist soil increased as solar radiation increased. Soil surface temperature in the white sheet was 6.3 and 10°C warmer than the air under solar radiation conditions of 350 and 700 W ·m-2 (about 700 and 1400 μmol·m-2·s-1), which was 3 and 2°C cooler than soil the black and gray plug sheets, respectively. These data indicate plug sheet color influences soil surface temperature, but not as much as solar radiation does. Preventing high solar radiation during the summer is more critical than plug sheet color.

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IMPROVEMENT OF PEPPER FRUIT QUALITY AND TIMING OF HARVEST BY SHADING UNDER HIGH SOLAR RADIATION CONDITIONS

Acta Horticulturae ◽

10.17660/actahortic.1986.191.23 ◽

1986 ◽

pp. 221-228 ◽

Cited By ~ 1

Author(s):

I. Rylski

Keyword(s):

Solar Radiation ◽

Fruit Quality ◽

High Solar Radiation ◽

Pepper Fruit ◽

Radiation Conditions

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A Simplified Simulation Model for Predicting Radiative Transfer in Long Street Canyons under High Solar Radiation Conditions

Energies ◽

10.3390/en81212383 ◽

2015 ◽

Vol 8 (12) ◽

pp. 13540-13558 ◽

Cited By ~ 4

Author(s):

Carlos Rubio-Bellido ◽

Jesús Pulido-Arcas ◽

Benito Sánchez-Montañés

Keyword(s):

Solar Radiation ◽

Radiative Transfer ◽

Simulation Model ◽

Street Canyons ◽

High Solar Radiation ◽

Radiation Conditions

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Implementation of a modified P&O-MPPT algorithm adapted for varying solar radiation conditions

Electrical Engineering ◽

10.1007/s00202-016-0457-3 ◽

2016 ◽

Vol 99 (3) ◽

pp. 839-846 ◽

Cited By ~ 13

Author(s):

Abdelhakim Belkaid ◽

Ilhami Colak ◽

Korhan Kayisli

Keyword(s):

Solar Radiation ◽

Radiation Conditions

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The Potential of Solar Air Heating in the Turkish Industrial Sector

Periodica Polytechnica Mechanical Engineering ◽

10.3311/ppme.13028 ◽

2018 ◽

Vol 63 (1) ◽

pp. 57-66

Author(s):

Balázs Bokor ◽

Hacer Akhan ◽

Dogan Eryener ◽

László Kajtár

Keyword(s):

Solar Radiation ◽

Energy Savings ◽

Measurement Data ◽

Industrial Sector ◽

Climatic Conditions ◽

Cold Climate ◽

Conventional Heating ◽

Industrial Building ◽

High Solar Radiation ◽

Mathematical Correlation

Transpired solar collector (TSC) systems are simple solutions for the preheating of ventilation air with solar energy. Their performance is a function of several environmental factors, so the climatic conditions of the location play an important role. In this paper, the effect of different climatic zones on the thermal performance of the TSC is investigated. To exclude other sources of influence, the same reference industrial building is examined in four Turkish locations (Antalya, Istanbul, Ankara and Sivas) representing different climatic conditions. RETScreen simulation is carried out for all four regions to obtain the drop of conventional heating requirement in case absorber azimuth of 0°, 45° and 90°. To illustrate the performance, temperature rise, heating energy savings and annual solar fraction are presented. Generally, it can be stated that a location with cold climate and high solar radiation at the same time benefits most from the use of a TSC system. A mathematical correlation has been found showing the solar fraction's dependence on solar radiation and heating degree days. Finally, simulation results have been compared to a set of measurement data from an industrial building's TSC system near Istanbul.

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