New method for quantitatively assessing susceptibility of citrus fruit to oleocellosis development and some factors that affect its expression

1998 ◽  
Vol 38 (3) ◽  
pp. 279 ◽  
Author(s):  
B. L. Wild
Keyword(s):  
Carbon Dioxide ◽  
Environmental Factors ◽  
Citrus Fruit ◽  
Laboratory Method ◽  
Sensitivity Testing ◽  
Oil Glands ◽  
Citrus Peel ◽  
Rate Of Development ◽  
Carbon Dioxide Concentrations ◽  
Colour Development

Summary. A quantitative laboratory method for determining the susceptibility of citrus fruit to oleocellosis (rind oil damage) has been developed. This method allows the evaluation of various factors which govern the extent of rind oil damage to the rind. By using this method, it has been established that the development of oleocellosis symptoms was affected by temperature, with temperatures <10˚C reducing the rate of development of the disorder. Unfortunately, when the temperature was raised again after storage, oleocellosis development proceeded as normal. Other environmental factors such as oxygen and carbon dioxide concentrations were also shown to affect the rate and extent of colour development of the rind blemish. This method of determining sensitivity of citrus peel to rind oil also established that the degree of surface exposure to sunlight increased the rind’s susceptibility to the oil. The effects of different coatings and chemicals which may affect the toxicity of the rind oils were also investigated, with artificial wax coatings being shown to reduce oil damage by up to 35%. This finding indicates the importance of thorough wax application to fruit. The tape method of sensitivity testing, as illustrated in this paper, also demonstrates that variations in oleocellosis development are not only due to changes in the pressure required to break the oil glands but also the ability of the peel to tolerate the released oil.

Redroot Pigweed (Amaranthus retroflexus) Seed Germination Responses to Afterripening, Temperature, Ethylene, and Some Other Environmental Factors

Weed Science ◽  
1980 ◽  
Vol 28 (5) ◽  
pp. 543-548 ◽  
Author(s):  
Mark W. Schonbeck ◽  
Grant H. Egley
Keyword(s):  
Carbon Dioxide ◽  
Environmental Factors ◽  
Water Potential ◽  
Continuous Light ◽  
Potassium Nitrate ◽  
Amaranthus Retroflexus ◽  
Dry Storage ◽  
Redroot Pigweed ◽  
Carbon Dioxide Concentrations ◽  
Favorable Conditions

Germination responses of redroot pigweed (Amaranthus retroflexusL.) seeds to temperature, water potential, atmospheric ethylene and carbon dioxide concentrations, light, and nitrate ion were examined individually. Seeds kept in dry storage at −20 C and tested within 2 yr of harvest germinated at 35 C (12 to 25%) or 39.5 C (40 to 65%), but only 0 to 2% at 30 C and below. Germination at 35 C was prevented by water potentials below −4 bars. When seeds were kept in dry storage at 24 to 28 C, afterripening became evident within 2 months. After storage at this temperature for 4 yr, seeds showed 38% germination at 14 C, 40% at 35 C and −8 bars water potential, and over 90% under more favorable conditions. Ethylene (1 to 100 ppmv) or continuous light enhanced germination at 30 C regardless of degrees of afterripening, although the ethylene effect was most dramatic in nonafterripened seeds. Ethylene at 100 ppmv caused 40% germination in these seeds, compared to 1% for controls. Neither carbon dioxide (0.001 to 4.5% v/v) nor dissolved potassium nitrate (0.02 to 0.2% w/v) influenced germination. These results are discussed in relation to environmental factors influencing field emergence of redroot pigweed.

Navel Orange Pitting Stimulated by Waxing and High Storage Temperature

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 520b-520
Author(s):  
Huating Dou ◽  
Peter D. Petracek ◽  
Craig Davis
Keyword(s):  
High Temperature ◽  
Storage Temperature ◽  
Chilling Injury ◽  
Citrus Fruit ◽  
Navel Orange ◽  
Oil Glands ◽  
C Storage ◽  
High Storage Temperature ◽  
Florida Citrus ◽  
Citrus Varieties

Navel oranges are reportedly susceptible to postharvest peel disorders, including chilling injury and aging/stem end rind breakdown. These and other physiological disorders are sometimes given the common term “navel rind breakdown.” California citrus industry reports on recent incidences of navel rind breakdown suggested that some instances of this disorder were similar to “postharvest pitting,” a disorder that we have observed in a number of Florida citrus varieties. Thus, we decided to define the morphology and etiology of pitting of `Washington' navel orange (Citrus sinensis L.) peel. The disorder was characterized by the collapse of clusters of oil glands and was stimulated by wax application and high temperature (≥13 °C) storage. Internal ethanol levels of waxed fruit stored at high temperature (13 or 21 °C) were significantly higher among fruit that developed pitting than those that did not. The pitting observed in these studies is comparable to previously observed navel orange disorders that have occurred without known cause. Navel orange pitting is morphologically and etiologically distinct from chilling injury and aging/stem end rind breakdown, but is similar to postharvest pitting of Florida citrus fruit.

scholarly journals Snowfall-albedo feedbacks could have led to deglaciation of snowball Earth starting from mid-latitudes

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Philipp de Vrese ◽  
Tobias Stacke ◽  
Jeremy Caves Rugenstein ◽  
Jason Goodman ◽  
Victor Brovkin
Keyword(s):  
Carbon Dioxide ◽  
Atmospheric Carbon Dioxide ◽  
Climate Models ◽  
Hydrological Cycle ◽  
High Surface ◽  
Dust Deposition ◽  
Carbon Dioxide Concentrations ◽  
Maximum Temperatures ◽  
Carbon Dioxide Levels ◽  
Earth’S Climate

AbstractSimple and complex climate models suggest a hard snowball – a completely ice-covered planet – is one of the steady-states of Earth’s climate. However, a seemingly insurmountable challenge to the hard-snowball hypothesis lies in the difficulty in explaining how the planet could have exited the glaciated state within a realistic range of atmospheric carbon dioxide concentrations. Here, we use simulations with the Earth system model MPI-ESM to demonstrate that terminal deglaciation could have been triggered by high dust deposition fluxes. In these simulations, deglaciation is not initiated in the tropics, where a strong hydrological cycle constantly regenerates fresh snow at the surface, which limits the dust accumulation and snow aging, resulting in a high surface albedo. Instead, comparatively low precipitation rates in the mid-latitudes in combination with high maximum temperatures facilitate lower albedos and snow dynamics that – for extreme dust fluxes – trigger deglaciation even at present-day carbon dioxide levels.

Carbon Capture and the Aluminium Industry: Preliminary Studies

2006 ◽  
Vol 3 (4) ◽  
pp. 297 ◽  
Author(s):  
Graham Jones ◽  
Gargi Joshi ◽  
Malcolm Clark ◽  
David McConchie
Keyword(s):  
Carbon Dioxide ◽  
Red Mud ◽  
Carbon Capture ◽  
Total Alkalinity ◽  
Industrial Processes ◽  
Carbonate Alkalinity ◽  
General Acceptance ◽  
Maximum Value ◽  
Carbon Dioxide Concentrations ◽  
Bicarbonate Alkalinity

Environmental Context. Carbon dioxide concentrations in the atmosphere are rising every year by 1.5–3.0 ppm and there is now a general acceptance that increased efforts must be made to reduce industrial sources of this greenhouse gas. Carbonation of red mud wastes produced by aluminium refineries has been carried out to study the capacity of these wastes to capture carbon dioxide. Removal is very rapid, with the added carbon dioxide recorded as a large increase in bicarbonate alkalinity. Although these results can only be considered preliminary, the experiments indicate that these wastes can potentially remove up to 15 million tonnes of carbon dioxide produced in Australia per annum. Furthermore, the carbonated waste can be used in other industrial processes to add further value to these waste materials. Abstract. Carbonation of raw red mud produced by aluminium refineries and a chemically and physically neutralized red mud (Bauxsol™) has been carried out to study the capacity of these wastes to capture carbon dioxide. After only 5 min of carbonation of raw red mud, total alkalinity dropped 85%. Hydroxide alkalinity was almost totally consumed, carbonate alkalinity dropped by 88%, and bicarbonate alkalinity increased to 728 mg L–1. After 24 min carbonation, the bicarbonate alkalinity reached its maximum value of 2377 mg L–1, and hydroxide and carbonate alkalinity were virtually absent. After 30 and 60 min carbonation, bicarbonate alkalinity started to decrease slightly as the pH of the slurry increased. After 5 min carbonation of Bauxsol™, total and bicarbonate alkalinity dropped 89% and 9%, respectively. After 20 min carbonation, bicarbonate alkalinity dropped another 11%, but after 30 min carbonation bicarbonate alkalinity increased 26% to levels found in the original Bauxsol material, and pH was stable. Based on these experiments, a calculation of the amount of carbon dioxide that could be removed annually at aluminium refineries in Australia is potentially 15 million tonnes, and suggests that further studies are necessary to maximize this carbon removal process. Furthermore, carbonation produces a product, which can potentially be used in other industrial and agricultural activities to remove toxic metals and nutrients.

Effect of prolonged exposure of rats to high carbon dioxide concentrations

1978 ◽  
Vol 86 (3) ◽  
pp. 1149-1151
Author(s):  
P. M. Gramenitskii ◽  
V. A. Galichii ◽  
N. V. Petrova ◽  
N. Yu. Leont'eva
Keyword(s):  
Carbon Dioxide ◽  
Prolonged Exposure ◽  
High Carbon ◽  
Carbon Dioxide Concentrations ◽  
High Carbon Dioxide

Elevated air carbon dioxide concentrations increase dissolved carbon leaching from a cropland soil

2011 ◽  
Vol 108 (1-3) ◽  
pp. 135-148 ◽  
Author(s):  
Jan Siemens ◽  
Andreas Pacholski ◽  
Katia Heiduk ◽  
Anette Giesemann ◽  
Ulrike Schulte ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Dissolved Carbon ◽  
Carbon Dioxide Concentrations

Why does the climate response to greenhouse warming and greenhouse cooling differ? 

2021 ◽  
Author(s):  
Jennifer Kay ◽  
Jason Chalmers
Keyword(s):  
Carbon Dioxide ◽  
Radiative Forcing ◽  
Climate Model ◽  
Temperature Response ◽  
Greenhouse Warming ◽  
Climate Response ◽  
Cloud Feedbacks ◽  
Surface Climate ◽  
Carbon Dioxide Concentrations ◽  
Radiative Feedbacks

&lt;p&gt;While the long-standing quest to constrain equilibrium climate sensitivity has resulted in intense scrutiny of the processes controlling idealized greenhouse warming, the processes controlling idealized greenhouse cooling have received less attention. Here, differences in the climate response to increased and decreased carbon dioxide concentrations are assessed in state-of-the-art fully coupled climate model experiments. One hundred and fifty years after an imposed instantaneous forcing change, surface global warming from a carbon dioxide doubling (abrupt-2xCO2, 2.43 K) is larger than the surface global cooling from a carbon dioxide halving (abrupt-0p5xCO2, 1.97 K). Both forcing and feedback differences explain these climate response differences. Multiple approaches show the radiative forcing for a carbon dioxide doubling is ~10% larger than for a carbon dioxide halving. In addition, radiative feedbacks are less negative in the doubling experiments than in the halving experiments. Specifically, less negative tropical shortwave cloud feedbacks and more positive subtropical cloud feedbacks lead to more greenhouse 2xCO2 warming than 0.5xCO2 greenhouse cooling. Motivated to directly isolate the influence of cloud feedbacks on these experiments, additional abrupt-2xCO2 and abrupt-0p5xCO2 experiments with disabled cloud-climate feedbacks were run. Comparison of these &amp;#8220;cloud-locked&amp;#8221; simulations with the original &amp;#8220;cloud active&amp;#8221; simulations shows cloud feedbacks help explain the nonlinear global surface temperature response to greenhouse warming and greenhouse cooling. Overall, these results demonstrate that both radiative forcing and radiative feedbacks are needed to explain differences in the surface climate response to increased and decreased carbon dioxide concentrations.&lt;/p&gt;

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