Review on thermal energy storage with phase change: materials, heat transfer analysis and applications

United States Agency for International Development

Heat tolerance in plants: An overview

A positive temperature coefficient is the term which has been used to indicate that an increase in solubility occurs as the temperature is raised, whereas a negative coefficient indicates a decrease in solubility with rise in temperature.

Effect of Temperature

As the result of intensive research and breeding efforts over the last 20 years, the yield potential and yield quality of cereals have been greatly improved. Nowadays, yield safety has gained more importance because of the forecasted climatic changes. Drought and high temperature are especially considered as key stress factors with high potential impact on crop yield. Yield safety can only be improved if future breeding attempts will be based on the valuable new knowledge acquired on the processes determining plant development and its responses to stress. Plant stress responses are very complex. Interactions between plant structure, function and the environment need to be investigated at various phases of plant development at the organismal, cellular as well as molecular levels in order to obtain a full picture. The results achieved so far in this field indicate that various plant organs, in a definite hierarchy and in interaction with each other, are involved in determining crop yield under stress. Here we attempt to summarize the currently available information on cereal reproduction under drought and heat stress and to give an outlook towards potential strategies to improve yield safety in cereals.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-3040.2007.01727.x

The effect of drought and heat stress on reproductive processes in cereals.

Greenhouse cladding materials are an important part of greenhouse design. The cladding material controls the light transmission and distribution over the plants within the greenhouse, thereby exerting a major influence on the overall yield. Greenhouse claddings are typically translucent materials offering more diffusive transmission than reflection, however the reflective properties of the films offer a potential route to increasing the surface albedo of the local environment. We model thermal properties by modelling the films based on their optical transmissions and reflections. We can use this data to estimate their albedo and determine the amount of short wave radiation that will be transmitted/reflected/blocked by the materials and how it can influence the local environment.

Optical and thermal properties of commercial polymer film, modeling the albedo effect

Freezing damage has been reported to be associated with apical abortion (blindness) in calabrese, preventing the formation of a marketable head. In the past, laboratory based experiments studying t...

The effects of radiation frost on freezing damage and apical abortion in calabrese (Brassica oleracea var. italica) transplants

SummaryEffects of organic and inorganic nitrogen fertilizers and soil moisture content were determined on the emergence of lettuce seedlings in controlled environment conditions. The effect of various nitrogen fertilizers and potassium chloride were also studied on emergence of lettuce and carrot seedlings in the field. Seedling emergence declined with increasing rate of applied nitrogen fertilizer, irrespective of the form supplied. However, fewer seedlings emerged with ammonium nitrate under dry soil conditions compared with organic sources, whereas the opposite was true in soil with a high moisture content. There was little effect of applied potassium chloride on seedling emergence. Factors affecting emergence of seedlings in soil amended with organic and inorganic N fertilizers are discussed.

Effects of organic and inorganic fertilizers on the seedling emergence of vegetable crops.

Prediction of cropping in june-bearing strawberries

Yield, fruit quality, Ca and K uptake, and distribution were examined in plum tomato Lycopercicum esculantum c.v. DRK 2003 grown under an infrared reflective filter designed to reduce temperature in glasshouses. The tomato plants were grown in a hydroponic system in two identical compartments, one covered with an infrared reflective filter and another without the filter. Two weeks after anthesis, fruits in the unfiltered compartment were 16% larger than those in the filtered compartment but Ca concentration was 12% less. Accelerated fruit growth caused by high temperature in the unfiltered compartment reduced Ca concentration in the fruits in the early stages of growth and, as a result, induced BER. In the unfiltered compartment 35% of the fruits had BER compared to none in the filtered compartment. Mature fruits in the unfiltered compartment had a K concentration 15% greater than fruits in the filtered compartment. High temperature appears to reduce Ca accumulation but increase K concentration of the fruit. To control BER, rapid fruit growth caused by high temperature should be avoided.

Paul Hadley

Papers

Optical and thermal properties of commercial polymer film, modeling the albedo effect

The effects of radiation frost on freezing damage and apical abortion in calabrese (Brassica oleracea var. italica) transplants

Effects of organic and inorganic fertilizers on the seedling emergence of vegetable crops.

Prediction of cropping in june-bearing strawberries

Fruit growth and Ca and K accumulation in the fruits of tomato grown under a spectral filter