Freezing media affect cooling rate and regrowth of KSC 28 apple rootstock

1997 ◽  
Vol 77 (3) ◽  
pp. 469-471 ◽  
Author(s):  
Jean-Pierre Privé ◽  
Charlie Embree
Keyword(s):  
Cooling Rate ◽  
Cold Hardiness ◽  
Temperature Gradients ◽  
Controlled Environment ◽  
Uniform Temperature ◽  
Apple Rootstock ◽  
Cooling Rates ◽  
Root Regrowth ◽  
Plastic Bag ◽  
Environment Chamber

To examine the effect that media have on cooling rates and subsequent plant regrowth, bare-rooted Kentville Select Clone 28 (KSC28) apple (Malus domestica Borkh.) roots were placed in various media (water, sawdust, soilless mixture and plastic bag) and set in a controlled environment chamber preset to −12 °C. Cooling rates differed between media with water and the plastic bag requiring the most and the least time to reach −12 °C, respectively. Shoot and root regrowth were similar for all treatments except water, which was significantly reduced. The plastic bag treatment provided the most uniform temperature gradients throughout the root system and the fastest cooling rate, was the easiest to handle, and allowed good regrowth. Key words: KSC28 apple rootstock, sawdust, soilless mix, cold hardiness testing

Cooling Rates of Brake Drums and Discs

1965 ◽  
Vol 180 (1) ◽  
pp. 191-205 ◽  
Author(s):  
T.P. Newcomb ◽  
N. Millner
Keyword(s):  
Cooling Rate ◽  
Air Flow ◽  
Vehicle Speed ◽  
Uniform Temperature ◽  
Cooling Rates ◽  
Size And Shape ◽  
Slip Ring ◽  
Disc Brakes ◽  
Shape And Size ◽  
Time Plot

An investigation has been made of the rates of cooling of vehicle brake drums and discs. Thermocouples were inserted in the drums and discs and in the wheel hubs and their outputs fed via slip ring units to meters mounted inside the vehicle. The drums or discs were heated to a uniform temperature of 300°-400°C by drag braking and the rate at which they cooled measured while the vehicle was driven at constant speed. Measurements were made at various speeds in the range 0 to 90 mile/h. From the log (temperature) against time plot a cooling coefficient bv was determined. It is shown that at a vehicle speed v the quantity bv can be expressed in the form bv = b0 +Kv0·8 where b0 represents the loss of heat to the hub and K is a constant depending on the size and shape of the drum or disc. Values of these constants have been determined on a variety of cars having discs and drums varying from 7 in to 11 in diameter and on a lorry fitted with 16·75 in diameter drums. Cooling rates are shown to depend on shape and size of the disc or drum. Results show that the cooling rates of front brakes are about 20 per cent higher than the rear brakes and that front discs cool about 25 per cent more quickly than the corresponding drum size recommended for the same vehicle. The cooling rate of front discs did not change when wire wheels were fitted instead of solid wheels. Ventilated discs and solid discs were also compared. The effect of fitting dust shields on disc brakes is shown to reduce the cooling rates by about 30 per cent. The effect of otherwise disturbing the air flow was studied.

scholarly journals Cooling and Warming Effects on Cold Hardiness Estimations of Three Woody Ornamental Taxa

HortScience ◽  
1992 ◽  
Vol 27 (12) ◽  
pp. 1308-1309 ◽  
Author(s):  
C.L. Haynes ◽  
O.M. Lindstrom ◽  
M.A. Dirr
Keyword(s):  
Cooling Rate ◽  
Cold Hardiness ◽  
Cooling Rates ◽  
Woody Ornamental

Cooling treatments of 2, 4, and 6C/hour or warming at 25, 4, or 0C influenced the cold hardiness estimates of x Cupressocyparis leylandii (A.B. Jacks. and Dallim.) Dallim. and A.B. Jacks. (Leyland cypress), Lagerstroemia indica L. (crape myrtle), and Photinia ×fraseri Dress `Birmingham' (redtip photinia) at four times during the year. New growth from all taxa, especially spring growth, was injured or killed at higher temperatures by the fastest cooling rate and/or by warming at 25C. Cold hardiness of Leyland cypress was unaffected by the cooling and warming treatments. Crape myrtle had a significantly higher lowest survival temperature (LST) when warmed at 25C than at 4 or 0C. Photinia leaves and stems cooled at 6C/hour or warmed at 25C generally resulted in a higher LST than those cooled more slowly or warmed at lower temperatures. Cooling rates of 14C/hour and warming at 0 to 4C should be used in freeze tests with Leyland cypress and crape myrtle. For leaves and stems of photinia, 2C/hour cooling and warming at 0 to 4C should be used.

scholarly journals SEASONAL CHANGE IN COLD HARDINESS AND DAYS TO BUDBREAK OF RUBUS IDAEUS L. `CHILCOTIN', `CHILLIWACK', `MEEKER', AND `WILLAMETTE'

HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 655a-655 ◽  
Author(s):  
Patrick P. Moore ◽  
Rita L. Hummel
Keyword(s):  
Laboratory Tests ◽  
Cold Hardiness ◽  
Rubus Idaeus ◽  
Controlled Environment ◽  
Bud Break ◽  
Test Results ◽  
Red Raspberry ◽  
Bud Growth ◽  
Environment Chamber ◽  
Freeze Test

Days to bud break and freezing tolerance of `Chilcotin', `Chilliwack', `Meeker' and `Willamette' red raspberry were measured during the 1990-1991 winter and at monthly intervals from mid-September 1991 through mid-March 1992. Canes were harvested from the field and cut into two-bud samples which were either frozen in laboratory tests or held with cut stem ends in water in a controlled environment chamber and monitored daily until bud growth was observed. Viability was estimated by visual browning after exposure to controlled laboratory freezing treatments. In general, freeze test results indicated `Meeker' and `Willamette' were not as hardy as `Chilliwack' and `Chilcotin' in late fall and midwinter but retained their hardiness longer in spring. Results for 1990-1991 indicated the greatest delay in days to bud break occurred in midwinter.

The effect of cooling rate on crystallization behavior and tensile properties of CF/PEEK composites

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Guangming Dai ◽  
Lihua Zhan ◽  
Chenglong Guan ◽  
Minghui Huang
Keyword(s):  
Cooling Rate ◽  
Crystallization Temperature ◽  
Crystallization Behavior ◽  
Crystalline Polymer ◽  
Scanning Calorimetry ◽  
Nonisothermal Crystallization ◽  
Cooling Rates ◽  
Control Range ◽  
Temperature Range ◽  
Transverse Tensile

Abstract In this study, the differential scanning calorimetry (DSC) tests were performed to measure the nonisothermal crystallization behavior of carbon fiber reinforced polyether ether ketone (CF/PEEK) composites under different cooling rates. The characteristic parameters of crystallization were obtained, and the nonisothermal crystallization model was established. The crystallization temperature range of the material at different cooling rates was predicted by the model. The unidirectional laminates were fabricated at different cooling rates in the crystallization temperature range. The results showed that the crystallization temperature range shifted to a lower temperature with the increase of cooling rate, the established nonisothermal crystallization model was consistent with the DSC test results. It is feasible to shorten the cooling control range from the whole process to the crystallization range. The crystallinity and transverse tensile strength declined significantly with the increase of the cooling rate in the crystallization temperature range. The research results provided theoretical support for the selection of cooling conditions and temperature control range, which could be applied to the thermoforming process of semi-crystalline polymer matrixed composites to improve the manufacturing efficiency.

TOLERANCE OF EARLY-MATURING SOYBEAN CULTIVARS TO METRIBUZIN

1986 ◽  
Vol 66 (1) ◽  
pp. 125-130 ◽  
Author(s):  
G. H. FRIESEN ◽  
D. A. WALL
Keyword(s):  
Sandy Loam ◽  
Controlled Environment ◽  
Clay Loam ◽  
Clay Loam Soil ◽  
Soybean Cultivars ◽  
Early Maturing ◽  
Glycine Max L ◽  
Loam Soil ◽  
Environment Chamber ◽  
Chamber Studies

McCall, Maple Presto, Maple Amber and OT80-3 soybean (Glycine max (L.) Merr.) cultivars were evaluated under field conditions for their response to metribuzin. Maple Amber was found to be less tolerant than the other cultivars. In controlled environment chamber studies, injury to this cultivar was more severe on a sandy loam soil than on a clay loam soil. Fall applications of metribuzin, alone or tank-mixed with trifluralin, were tolerant to Maple Amber soybeans and such applications may offer a practical alternative to spring treatments for broad spectrum weed control in the less tolerant soybean cultivars grown in Manitoba.Key words: Metribuzin, trifluralin, preplant incorporation, fall treatments, soybean cultivars

Effects of RE on Critical Cooling Rate of Bearing-B Steel

2012 ◽  
Vol 535-537 ◽  
pp. 761-763 ◽  
Author(s):  
Yi Sheng Zhao ◽  
Xin Ming Zhang ◽  
Zhi Guo Gao
Keyword(s):  
Phase Change ◽  
Cooling Rate ◽  
Experimental Results ◽  
Cooling Rates ◽  
Critical Cooling Rate ◽  
The Law

The law of phase change of bearing-B steel during continual cooling was studied by adopting dilatometer. The CCT curves of bearing-B steel were drawn, and the effects of RE on critical cooling rates were studied. The experimental results show that the start temperatures of martensite TM was decreased from 438 to 404°C. The critical cooling rate was simultaneously decreased from 33 to 15°C/s.

Effects of the Cooling Rate on the Acoustic Properties of Pb-10Sn Solder

2012 ◽  
Vol 729 ◽  
pp. 356-360
Author(s):  
Endre Harkai ◽  
Tamás Hurtony ◽  
Péter Gordon
Keyword(s):  
Sound Velocity ◽  
Cooling Rate ◽  
Acoustic Microscopy ◽  
Acoustic Properties ◽  
Scanning Acoustic Microscopy ◽  
Cooling Rates ◽  
Reliability Parameters ◽  
Microscopy Characterization ◽  
The Given

Microhardness and sound velocity were measured in case of differently prepared solder samples. The used Pb-10Sn solder samples were melted then cooled down applying different cooling rates. These procedures caused variant microstructure thus different microhardness and sound velocity values. The sound velocity was measured by means of scanning acoustic microscopy. Characterization of solder materials by acoustic microscopy gives the possibility to non-destructively estimate mechanical and reliability parameters of the given material.

The effect of various cooling rates on the membrane ultrastructure of frozen human erythrocytes and its relation to the extent of haemolysis after thawing

1981 ◽  
Vol 49 (1) ◽  
pp. 369-382
Author(s):  
S. Fujikawa
Keyword(s):  
Cooling Rate ◽  
Human Erythrocytes ◽  
Ice Crystals ◽  
Erythrocyte Membranes ◽  
Ultrastructural Changes ◽  
Cooling Rates ◽  
Intracellular Ice ◽  
Frozen State ◽  
Membrane Ultrastructure ◽  
Fast Freezing

Human erythrocytes suspended in buffered isotonic saline were frozen to the temperature of liquid nitrogen at various cooling rates of 3, 140, 700, 1800, 3500, 8000 and 11 500 deg. C/min. The membrane ultrastructure in the frozen state and the extent of haemolysis after thawing were examined at each cooling rate. As the cooling rates increased from 3 to 3500 deg. C/min, the extent of lysis gradually decreased, but further increase in cooling rates in excess of 8000 deg. C/min resulted in an abrupt increase of lysis. Membrane-associated vesicles devoid of intramembrane particles (IMPs) were formed in the erythrocyte membranes frozen at cooling rates slower than 1800 deg. C/min. The frequency and size of these vesicles were highly cooling-rate-dependent and they were no longer formed in the erythrocyte membranes frozen at cooling rates faster than 3500 deg. C/min. Another membrane ultrastructural change associated closely with the formation of intracellular ice crystals appeared at cooling rates faster than 8000 deg. C/min. The membrane regions in direct contact with intracellular ice crystals were physically damaged and had an appearance resembling worm-eaten spots. The erythrocytes frozen at a cooling rate of 3500 deg. C/min exhibited ultrastructural integrity of the membrane by avoiding the membrane changes caused by either slow or fast freezing. It is suggested, from the close relation between membrane ultrastructure and the extent of haemolysis, that the ultrastructural integrity of membrane in the frozen state is important for avoiding haemolysis after thawing, and that the membrane ultrastructural changes caused by both slow and fast freezing were responsible for the lysis after thawing.

Humidity Effects on Porous Silica Thin Films

1995 ◽  
Vol 411 ◽  
Author(s):  
J. R. Kokan ◽  
R. A. Gerhardt
Keyword(s):  
Thin Films ◽  
Ac Conductivity ◽  
Sol Gel ◽  
Porous Silica ◽  
Controlled Environment ◽  
Alkali Ions ◽  
Humidity Effects ◽  
Silica Thin Films ◽  
Environment Chamber ◽  
Humidity Sensitivity

ABSTRACTImpedance Spectroscopy is being used to study the humidity sensitivity of porous silica thin films. The films are processed via a colloidal sol-gel method which leaves some remnant potassium and sodium. Previous work on bulk porous silica samples processed by the same method showed that the dielectric properties and ac conductivity were very sensitive to changes in humidity. The aim of this work was to determine if the same dependencies could be found in the thin films. The capacitance, dielectric loss, and ac conductivity of the films were measured in a controlled environment chamber from 20–80% RH for frequencies ranging from 10Hz–10MHz. In addition to characterizing films with varying amounts of residual alkali ions obtained through leaching, we have also measured films that were surface doped with controlled amounts of KCl, LiCl, or NaCl. Relative humidity dependencies in the films are not as dramatic as in the bulk samples. The reasons for this behavior are not yet clear, but may be associated with the porosity, thickness, and surface area of the films.

Phase Selection in Sub-Rapidly Solidified Au-20Sn Alloys

2015 ◽  
Vol 817 ◽  
pp. 325-330
Author(s):  
Yu Hai Qu ◽  
Kai Jin Yang ◽  
Yan Tian Zhou ◽  
Yong Mao ◽  
Wei Zhang ◽  
...  
Keyword(s):  
Cooling Rate ◽  
Nucleation Theory ◽  
Classical Nucleation Theory ◽  
Copper Mold ◽  
Cooling Rates ◽  
Phase Selection ◽  
Graphite Mold ◽  
Injection Casting ◽  
Rapidly Solidified ◽  
Ausn Phase

The sub-rapidly solidified Au-20Sn eutectic alloys were prepared by four different solidification pathways, such as, graphite mold conventional casting, graphite mold injection casting, copper mold injection casting, and water-cooled copper mold suction casting. The precipitating sequences of competing primary phases of sub-rapidly solidified Au-20Sn alloys with four different cooling rates were investigated. The results show that phase selection process is related to the cooling rates during sub-rapid solidification process. The primary ζ'-Au5Sn phase with developed dendrites precipitate at low cooling rate (2.4×10−4.2×102K/min) and the morphologies of the primary ζ'-Au5Sn change to rosette-like at higher cooling rate (9.0×103K/min). While the cooling rate reaches to 3.5×104K/min, the primary ζ'-Au5Sn phase can be suppressed but δ-AuSn phase will precipitate prior to the ζ'-Au5Sn phase. On the basis of the classical nucleation theory and transient nucleation theory, the process of competitive nucleation between the ζ'-Au5Sn phase and the δ-AuSn phase were analyzed for sub-rapid solidified Au-20Sn alloy. The theoretical calculations are consistent with the experimental investigations.

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