Ultra Low Temperature Production and Control in Environmental Testing and Application Facilities

1960 ◽  
pp. 160-173
Author(s):  
J. Meisler
Keyword(s):  
Low Temperature ◽  
Environmental Testing ◽  
And Control

Temperature-induced variation in reproductive success: field and control experiments with the C4 grass Echinochloa crus-galli

1991 ◽  
Vol 69 (7) ◽  
pp. 1577-1582 ◽  
Author(s):  
Catherine Potvin
Keyword(s):  
Low Temperature ◽  
Biomass Accumulation ◽  
Joint Effect ◽  
The Other ◽  
Maximum Temperature ◽  
High Latitudes ◽  
Controlled Experiments ◽  
Weather Patterns ◽  
C4 Grass ◽  
And Control

To examine the influence of weather patterns on the flowering of a C4 plant, 11 transplant gardens were sown with seeds of Echinochloa crus-galli var. crus-galli within and beyond the species range. Both the isolated effect of climate and the joint effect of competition and soil quality on the flowering of E. crus-galli were analyzed. Although vegetative growth was significantly more vigorous in the southernmost site, Echinochloa plants were able to grow actively even at high latitudes. Conversely, flowering decreased gradually from south to north. The maximum temperature in August was the best predictor of floral emergence. Data from controlled experiments confirmed that flowering of E. crus-galli was size independent, and temperature was shown to have an effect on biomass accumulation and allocation as well as on floral emergence. Plants grown in the coolest thermoperiod produced a small number of heavy seeds, whose germinability was superior to that of plants grown in the other temperature treatments. Finally, the results indicate that maternal families represent a significant source of variability for reproductive characteristics. The presence of genetic effects suggests that E. crus-galli has the potential for further evolution with regard to temperature. Key words: flowering, reproduction, low temperature, C4 plants, Echinochloa crus-galli.

scholarly journals A Novel Transportation Method Based on Dynamic Control of Ripening Environment

2020 ◽  
Vol 13 (5) ◽  
pp. 58-66
Author(s):  
Xinyu Liu ◽  
◽  
Xiaojie Jin
Keyword(s):  
Low Temperature ◽  
Fruits And Vegetables ◽  
Control Method ◽  
Volume Fraction ◽  
Dynamic Control ◽  
Exogenous Ethylene ◽  
Quality Of Products ◽  
And Control ◽  
Air Circulation

The dynamic control of atmosphere is an important factor for guaranteeing the quality of climacteric products during transportation. As atmosphere changes, respiration climacteric products would rot because of overripeness, thus leading to loss. Moreover, climacteric products must be ripened artificially when delivered to the destination, thereby causing economic waste. In this study, a new transportation method based on dynamic control of ripening environment was designed.The ripeness control method based on the dynamic control of ripening atmosphere was presented to accomplish quality safety during transportation as well as avoid a subsequent extra process of ripening. The transportation method was employed to stem from the ethylene’s ripening effect on climacteric fruits and vegetables. The ethylene generator and air circulation unit, which dynamically regulate and control the dual regional atmosphere of carriages during transportation, were quantitatively controlled by the central treatment layer. Ripeness level could be regulated by controlling the temperatures and time of exogenous ethylene release, to control the quality of products and ripen them. The proposed method was proven feasible through experiments. Results demonstrate that a volume fraction of 0.01% exogenous ethylene allows bananas’ respiratory intensity to reach the peak early; meanwhile, moderate low temperature (16 °C) can enable ethylene peak to appear in advance. Therefore, bananas’ ripeness can be controlled by changing temperatures and the ripening environment when transporting. This study can provide references for the control of products’ ripeness during transportation.

C4 Photosynthesis: Activities of Photosynthetic Enzymes in a Virescent Mutant of Maize Having a Low-Temperature Induced Chloroplast Ribosome Deficiency

1988 ◽  
Vol 15 (3) ◽  
pp. 385 ◽  
Author(s):  
GE Edwards ◽  
CLD Jenkins
Keyword(s):  
Low Temperature ◽  
Enzyme Activities ◽  
Wild Type ◽  
Carboxylase Activity ◽  
Pale Yellow ◽  
Photosynthetic Enzymes ◽  
Normal Green ◽  
Normal Enzyme ◽  
Virescent Mutant ◽  
And Control

A virescent mutant of maize (v16/v16), which has a low temperature induced deficiency in 70S ribosomes, was used to examine whether the enzymes of the C4 pathway and other photosynthetic enzymes are synthesised on chloroplast ribosomes. The mutant and control plants were grown at 20°C and 30°C and the rates of photosynthesis and enzyme activities were compared. There was no photosynthesis in v16/v16 grown at 20°C (pale yellow), while plants grown at 30°C (normal green) had rates equivalent to the wild type and normal enzyme activities. On a leaf area basis, with v16/v16 grown at 20°C, the activity of ribulose 1,5-bisphosphate (RuP2) carboxylase was only 2% that of the wild type grown at this temperature, while the activities of enzymes of the C4 cycle were much higher (as a percentage of the wild type activity: pyruvate,PI dikinase, 22%; NADP-malate dehydrogenase, 35%; NADP-malic enzyme, 47%; and phosphoenolpyruvate (PEP) carboxylase, 68%). In another experiment v16/v16 plants were grown initially at 30°C, then transferred to 20°C. After transfer to 20°C leaves previously formed under 30°C remained green and had normal rates of photosynthesis and enzyme activities, but newly formed leaves were pale yellow (only 11% as much Chl) and had low photosynthesis rates (2% of normal) and RuP2 carboxylase activity (5% of control). However, there was high activity of eight enzymes of the C4 cycle. The low activity of RuP2 carboxylase in the mutant grown at 20°C is consistent with the requirement of 70S ribosomes for its synthesis, while the high activities of enzymes of the C4 cycle, including those which are chloroplastic, suggest their synthesis is nuclear-encoded.

Metallurgical Design and Development of High-Grade Line Pipe

2012 ◽  
Author(s):  
Takuya Hara ◽  
Taishi Fujishiro ◽  
Yasuhiro Shinohara ◽  
Eiji Tsuru ◽  
Naoki Doi ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Low Temperature ◽  
Cost Savings ◽  
High Strength ◽  
Design And Development ◽  
Line Pipe ◽  
Good Balance ◽  
Low Temperature Toughness ◽  
And Control ◽  
High Deformability

The application of high-strength line pipes has enabled pipelines to operate at high pressure, generating cost savings for both gas transportation and construction. In general, high-strength line pipes require crack initiation resistance and crack arrestability at low temperatures, as well as field weldability. High strength and deformability for strain-based design and excellent sour resistance are also required. Moreover, composite properties are often required for high-strength line pipes. This paper describes our progress in this field with regard to metallurgical design and development. Metallurgical design aimed at achieving a good balance between strength, low temperature toughness and deformability for strain-based design is also described from the perspectives of grain refinement, microstructure and chemical composition. Metallurgical design focused on a good balance between strength and sour resistance in limited low chemical composition is described from the perspectives of microstructure and control to chemical composition and center segregation. These efforts have led to the development of high-strength heavy wall line pipes of API X60 to X100 grades offering excellent low temperature toughness and high deformability for stain-based design, while API grades X65 to X70 with good sour resistance have also been developed.

scholarly journals Chilling Prevention on Banana ‘Nanica’ in the Field with Bagging

2018 ◽  
Vol 10 (3) ◽  
pp. 122
Author(s):  
Juliana Domingues Lima ◽  
Danilo Eduardo Rozane ◽  
Eduardo Nardini Gomes ◽  
Silvia Helena Modenese Gorla da Silva ◽  
Wilson Da Silva Moraes ◽  
...  
Keyword(s):  
Low Temperature ◽  
Chilling Injury ◽  
Sao Paulo ◽  
Woven Fabric ◽  
São Paulo ◽  
Green Fruit ◽  
Kraft Paper ◽  
Randomized Design ◽  
Completely Randomized Design ◽  
And Control

Low temperature in the field causes chilling injury (CI) in banana and peel browning. The aim of this paper was to investigate the influence of different bagging materials and combinations on bunch development of banana (Musa AAA cv. Nanica) and the occurrence of CI. The study was carried in Jacupiranga, São Paulo, Brazil, in a completely randomized design in 2 × 9 factorial, two years of formation (2013 and 2014) and nine bagging materials, with eight replicates. Materials consisted in blue transparent polyethylene, white non-woven fabric, white opaque polyethylene, bubble wrap, white laminated non-woven fabric, double paper, blue transparent polyethylene plus kraft paper, blue transparent polyethylene plus white non-woven fabric and control (non-bagged). Fruits formed in both years showed low L* and C* values related to the CI index. On the coldest days of 2013 and 2014, bagging raised the temperature by only 1.91 and 3.17 °C, respectively. Depending on the year of bunch formation, the bagging materials influenced the period between flowering and harvest, but not the bunch mass. In the green fruit, the content of chlorophylls was lower in double paper, while L* was higher, but there were no differences in the content of phenols for the different materials. In mature fruits, CI index, L* and a* were not affected by the bagging materials, unlike coordinates b*, h° and C*, which were lower for double paper, with no difference between other materials and non-bagged fruits. Bagging materials did not prevent CI and did not reduce the peel browning intensity.

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