scholarly journals Additive Effects of Postharvest Calcium and Heat Treatment on Reducing Decay and Maintaining Quality in Apples

1994 ◽  
Vol 119 (1) ◽  
pp. 49-53 ◽  
Author(s):  
William S. Conway ◽  
Carl E. Sams ◽  
Chien Yi Wang ◽  
Judith A. Abbott
Keyword(s):  
Heat Treatment ◽  
Cell Wall ◽  
Calcium Chloride ◽  
Compression Test ◽  
Additive Effects ◽  
Pressure Infiltration ◽  
Chloride Solutions ◽  
Heat Treated ◽  
Golden Delicious

`Golden Delicious' apples (Malus domestics Borkh.) were treated with heat or CaCl2 solutions or a combination thereof to determine the effects of these treatments on decay and quality of fruit in storage. Heat treatment at 38C for 4 days, pressure infiltration with 2% or 4% solutions of CaCl2, or a combination of both, with heat following CaCl2 treatment affected decay and firmness during 6 months of storage at 0C. The heat treatment alone reduced decay caused by Botrytis cinerea (Pers.:Fr.) by ≈30%, while heat in combination with a 2% CaC12 solution reduced decay by ≈60 %. Calcium chloride solutions of 2% or 4% alone reduced decay by 40 % and 60 %, respectively. Heat treatments, either alone or in combination with CaC12 treatments, maintained firmness (80 N) best, followed by fruit infiltrated with 2% or 4% solutions of CaCl2 alone (70 N) and the nontreated controls (66 N). Instron Magness-Taylor and Instron compression test curves show that heat-treated fruit differed qualitatively and quantitatively from nonheated fruit. Heat treatment did not increase the amount of infiltrated Ca bound to the cell wall significantly, and a combination of heat treatment after CaCl2 infiltration increased surface injury over those fruit heated or infiltrated with CaCl2 solutions alone.

Surface Modification of Diamonds in Diamond/Al-Matrix Composite

2008 ◽  
Vol 59 ◽  
pp. 125-130 ◽  
Author(s):  
C. Edtmaier ◽  
Ludger Weber ◽  
Reza Tavangar
Keyword(s):  
Electron Microscopy ◽  
Heat Treatment ◽  
Treatment Temperature ◽  
Pressure Infiltration ◽  
Argon Gas ◽  
Diamond Particles ◽  
Heat Treated ◽  
Modified Surface ◽  
Al Matrix Composite ◽  
Al Matrix

Fe- or Mn-powders were mixed with the diamonds and the mixtures were heat treated under different gas atmospheres like hydrogen or argon gas and at varying temperatures in order to roughen the surface of the diamond particles. Subsequently the reaction layers are removed by the addition of aqueous solutions of HCl. The modified surface structure after the etching process is investigated by electron microscopy showing increased roughening of the formerly flat faces of the diamond particles with increasing heat treatment temperature. After drying the diamonds, composites were prepared by gas pressure infiltration with pure Al. For treatments in the temperature range from 750 to 850°C the thermal conductivity can be improved by up to 20 percent compared to composites based on un-treated powders.

Thermal Conductivity of Heat Treated and Non-Heat Treated Individual Multiwalled Carbon Nanotubes

2011 ◽  
Author(s):  
Michael F. P. Bifano ◽  
Pankaj B. Kaul ◽  
Vikas Prakash
Keyword(s):  
Thermal Conductivity ◽  
Heat Treatment ◽  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Multiwalled Carbon ◽  
Heat Treated Sample ◽  
Heat Treated ◽  
Treated Sample ◽  
Annealing Heat Treatment

Thermal conductivity measurements of commercially available CVD grown individual multiwalled carbon nanotubes (MWCNTs) are reported. The measurements are performed using the three-omega-based Wollaston T-Type probe method inside a scanning electron microscope (SEM). An average 385% increase in thermal conductivity is measured for those MWCNTs samples which undergo a 20 hour 3000°C post annealing heat treatment. However, in most samples qualitatively characterized defects are found to negate any advantage of the heat treatment process. The highest thermal conductivity measured is 893.0 W/mK and is of a heat-treated sample. These results will help to improve the quality of MWCNT production and aid in the development of highly efficient CNT-structured thermal management devices and engineering materials.

Solution Heat Treatment of 7075 Aluminum Alloy Affected on Anodic Oxide Layer

2016 ◽  
Vol 867 ◽  
pp. 19-23 ◽  
Author(s):  
Itsaree Iewkitthayakorn ◽  
Somjai Janudom ◽  
Narissara Mahathaninwong
Keyword(s):  
Heat Treatment ◽  
Oxide Film ◽  
Solution Heat Treatment ◽  
Treatment Time ◽  
Solution Treatment ◽  
Secondary Phase ◽  
Anodic Oxide ◽  
Al Alloy ◽  
Heat Treated

This research focused on the effect of solution heat treated microstructures on anodic oxide formations of casting 7075 Al alloy. The casting specimens were solution heat treated at 450°C for various holding. The results showed that the quality of anodic oxide film on the specimen with 4h solution heat treatment time was higher than that of at other conditions. Because its microstructures obtained the lowest amounts of secondary phase particles leading to improve the quality of oxide film and also reduce defects in oxide film. On the other hand, coarse black particles of Mg2Si formed increasingly in microstructures of specimens after solution treatment at prolong holding time of 8h and 16h resulted in discontinues oxide films forming on them.

scholarly journals Cell Membrane Stability and the Role of Calcium Infiltration in Postharvest Quality of Apples

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 815G-815
Author(s):  
G.A. Picchioni ◽  
A.E. Watada ◽  
W.S. Conway ◽  
B.D. Whitaker ◽  
C.E. Sams
Keyword(s):  
Membrane Lipid ◽  
Cellular Level ◽  
Postharvest Quality ◽  
Storage Quality ◽  
Pressure Infiltration ◽  
Cell Membrane Stability ◽  
Golden Delicious ◽  
And Storage

Postharvest CaCl2 pressure infiltration improves firmness and storage quality of apples but is still in the experimental stages. Its effectiveness could be increased if we had a better understanding of how Ca affects the tissue at the cellular level. `Golden Delicious' fruit were harvested from a commercial orchard and were pressure-infiltrated with CaCl2 (0%, 2%, or 4% w/v), stored for 6 months at 0C, and then for 7 days at 20C. Between harvest and the end of storage at 20C, the net breakdown of galactolipids and phospholipids decreased with increasing CaCl2 in infiltration solutions. During 0C storage, CaCl2-infiltrated fruit maintained greater concentrations of conjugated sterol lipids, and these lipid classes are thought to be closely associated with the plasma membrane. As membrane lipid alterations are viewed as a central factor in the senescence of fruits, Ca (from postharvest infiltration) may serve a major role in regulating fruit quality losses through its interactions with cell membranes.

scholarly journals Lipid Changes during Heat Treatment of Apple Fruit

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 782D-782
Author(s):  
Bruce D. Whitaker ◽  
Joshua D. Klein ◽  
William S. Conway
Keyword(s):  
Heat Treatment ◽  
Cell Wall ◽  
Membrane Lipid ◽  
Apple Fruit ◽  
Fruit Color ◽  
Fruit Firmness ◽  
Minor Components ◽  
Free Sterols ◽  
Class Composition ◽  
Golden Delicious

Postharvest heat treatment of apples maintains fruit firmness and reduces decay during storage. Four days at 38C are beneficial, but 1 or 2 days are detrimental. The cellular basis of these effects may involve changes in cell wall and membrane lipid metabolism. Lipids from hypodermal tissue of `Golden Delicious' apples were analyzed after 0, 1, 2, or 4 days at 38C. Major lipids included phospholipids (PL), free sterols (FS), steryl glycosides (SG), and cerebrosides (CB). Galactolipids (GL) were minor components. PL content fell ?10% after 1 day at 38C, was unchanged after 2 days, and began to rise again after 4 days. PL class composition did not change with heating, but fatty-acid unsaturation declined throughout. FS and CB content and composition changed little, whereas SG content cropped by ≈20% over 4 days. GL fell ≈50% during 1 day at 38C, with no change at days 2 or 4. A burst of PL catabolism followed by recovery of synthesis may in part explain the different effects of 1-, 2-, or 4-day heat treatments. GL loss (in plastids) may be related to the effect of heat on fruit color (yellowing).

scholarly journals Pilot Test for the Commercial Use of Postharvest Pressure Infiltration of Calcium into Apples to Maintain Fruit Quality in Storage

1994 ◽  
Vol 4 (3) ◽  
pp. 239-243 ◽  
Author(s):  
William S. Conway ◽  
Carl E. Sams ◽  
George A. Brown ◽  
William B. Beavers ◽  
Rowel B. Tobias ◽  
...  
Keyword(s):  
Fruit Quality ◽  
Calcium Concentration ◽  
Storage Conditions ◽  
First Year ◽  
Pilot Test ◽  
Skin Injury ◽  
Pressure Infiltration ◽  
Commercial Use ◽  
Golden Delicious

A pilot test was conducted over a 3-year period to determine the feasibility of using postharvest pressure infiltration of calcium into apples to maintain and/or improve the quality of fruit under commercial storage conditions. Fruits obtained from three different orchards were treated each year. `Golden Delicious' fruits were treated the first year, while `Delicious' fruits were treated the 2nd and 3rd years. In all treatments and years, there was a significant increase in calcium concentration of apples from all calcium chloride (CaCl2) treatments. In general, calcium concentration of treated fruit varied significantly among the three orchards. Firmness also varied among orchards, and was related to fruit calcium concentration. `Golden Delicious' apples were more susceptible to skin injury caused by CaCl2 treatment than were `Delicious' fruits. There was also an increase in infection as a result of some of the treatments, possibly due to injury caused to lenticels by the pressure applied or as a result of calcium injury.

Influence of Adopted Heat Treatments on Properties of Tri-Layer Composite AA2519 – AA1050 – Ti GR.5 Made by Explosive Cladding Method

2016 ◽  
Vol 687 ◽  
pp. 71-78
Author(s):  
Michał Najwer ◽  
Grzegorz Kwiatkowski
Keyword(s):  
Heat Treatment ◽  
Heat Treatments ◽  
Strength Test ◽  
Multilayer Material ◽  
Explosive Cladding ◽  
Tensile Strength Test ◽  
Heat Treated ◽  
Layer Composite ◽  
Structural Tests

The article shows the results of research on tri-layer composite AA2519-AA1050-Ti Gr. 5 made by explosive cladding method. Performed bond was heat treated in different conditions. Four specimens were heated in 530°C in 30 minutes, and after adopted different ways of cooling for each specimen. Used cooling in air and water. Additionally two specimens were aged at 150°C for 600 minutes. Last joint was heated at 420°C for 60 minutes and after was cooled in still air. For obtained joint were performed mechanical and technological tests. Tests included tensile strength test, yield strength test, ram strength test and bend test. Moreover performed structural tests, analysis of the chemical composition and hardness measurements. Based on the results evaluated the quality of joint, and described the influence of heat treatment on the properties of obtained multilayer material. Was found that as a result of explosive cladding, hardness in the interface increased. Heat treatments at temperature 530°C do not change properties. Only the heat treatment at temperature 420°C is decreasing hardness in the interface and in the whole cross section of the AA2519 layer.

scholarly journals Changes to Physical Properties of the Cell Wall and Polyuronides in Response to Heat Treatment of `Fuyu' Persimmon that Alleviate Chilling Injury

1997 ◽  
Vol 122 (5) ◽  
pp. 698-702 ◽  
Author(s):  
Allan B. Woolf ◽  
Elspeth A. MacRae ◽  
Karen J. Spooner ◽  
Robert J. Redgwell
Keyword(s):  
Heat Treatment ◽  
Cell Wall ◽  
Molecular Mass ◽  
Chilling Injury ◽  
Heat Treatments ◽  
Wall Material ◽  
Diospyros Kaki ◽  
Average Molecular Mass ◽  
Heat Treated ◽  
Subsequent Degradation

Modifications to solubilized cell wall polyuronides of sweet persimmon (Diospyros kaki L. `Fuyu') were examined during development of chilling injury (CI) during storage and in response to heat treatments that alleviated CI. Storage at 0 °C caused the solubilization of a polyuronide fraction that possessed a higher average molecular mass than polyuronide solubilized during normal ripening. The viscosity of this fraction was 30-times that of normally ripened fruit. Fruit heat-treated before or following storage contained a soluble polyuronide fraction with a markedly lower average molecular mass and decreased viscosity than in chilling injured fruit. Heat treatment also impeded an increase in viscosity of the cell wall material if applied before storage. CI (gelling) was related to the release of polyuronide from the cell wall during storage and its lack of subsequent degradation. Heat treatments retarded polyuronide release but promoted degradation of solubilized polyuronides.

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