PREDICTING THE TIME OF HATCH OF THE STRAWBERRY APHID, CHAETOSIPHON FRAGAEFOLII (HOMOPTERA: APHIDIDAE)

1984 ◽  
Vol 116 (8) ◽  
pp. 1131-1135 ◽  
Author(s):  
B.D. Frazer ◽  
D. A. Raworth
Keyword(s):  
Constant Temperature ◽  
Accurate Method ◽  
Effect Of Temperature ◽  
Controlled Environment ◽  
Egg Development ◽  
Thermal Threshold ◽  
Threshold Of Development ◽  
Time Of Collection

AbstractThe rate of hatch of overwintered eggs of the strawberry aphid, Chaetosiphon fragaefolii (Cockerell), at five temperatures in controlled environment chambers was used to determine the thermal threshold of development. Samples of eggs were taken from two field locations several times before hatch. These samples were subdivided and placed into two or three different constant temperature chambers. The day-degree requirements for hatching from the time of collection were estimated. These estimates corresponded to the number of day-degrees actually accumulated in the field between the time of egg collection and the time of hatching.This method of simulating the effect of temperature on egg development was an accurate method of predicting the time of hatch in the field at least 3 weeks prior to the observed time.

The effect of temperature on high-resolution TEM image contrast

1995 ◽  
Vol 53 ◽  
pp. 640-641
Author(s):  
T. Geipel ◽  
W. Mader ◽  
P. Pirouz
Keyword(s):  
Form Factor ◽  
Inelastic Scattering ◽  
Accurate Method ◽  
Waller Factor ◽  
Effect Of Temperature ◽  
Specimen Thickness ◽  
Influence Of Temperature ◽  
Debye Waller Factor ◽  
Influence Of Temperature On ◽  
Atomic Form Factor

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).

THE EFFECT OF TEMPERATURE ON THE RATE AND VARIATION OF OPERCULAR MOVEMENT IN FUNDULUS DIAPHANUS DIAPHANUS

1947 ◽  
Vol 25d (2) ◽  
pp. 91-95
Author(s):  
Benjamin N. Kropp
Keyword(s):  
Constant Temperature ◽  
Beat Frequency ◽  
Nervous Activity ◽  
Respiratory Movement ◽  
Effect Of Temperature ◽  
Temperature Range ◽  
Sources Of Variation ◽  
Fundulus Diaphanus

The rates of opercular beat of 16 specimens of Fundulus diaphanus diaphanus were recorded over a temperature range from 4.3° to 17.5 °C. in order to determine how this respiratory movement varied with temperature and some of the sources of variation in rate. While the rate of beat varies directly as the temperature, over a period of several hours at any constant temperature continuous recordings of the rate show recurring cycles of rise and fall in beat frequency that are chiefly responsible for the scatter of the observations. Both the duration of a cycle and the limits of rise and fall for each cycle are definitely set by the temperature. The possible dependence of these phenomena upon central nervous activity is discussed.

Effect of Temperature on the Synthesis of Jojoba Wax

1985 ◽  
Vol 12 (4) ◽  
pp. 355 ◽  
Author(s):  
RL Dunstone ◽  
A Benzioni ◽  
ML Tonnet ◽  
P Milthorpe ◽  
A Shani
Keyword(s):  
Field Studies ◽  
Effect Of Temperature ◽  
Maximum Temperature ◽  
Wax Ester ◽  
Controlled Environment ◽  
Percentage Elongation ◽  
Jojoba Wax ◽  
Seed Growth ◽  
The Mean ◽  
Long Chain

Seed was collected from jojoba [Simmondsia chinensis (Link) Schneider] plants growing at three field sites in two years. The wax percentage was determined by nuclear magnetic resonance and the compositions of the wax and the ethanolysis products (one site only) were determined by gas chromatography. The mean wax concentration varied from 49.2 to 55.1% over all sites and years. The percentage of long-chain wax esters (>C40) decreased linearly with increase in mean maximum temperature during the period of linear seed growth (r� = 0.93). The decrease in long-chain esters was associated with a decrease in the C22 and C24 fatty acids and alcohols. Data from controlled environment studies and from field studies were used to assess the effect of temperature on the percentage elongation, reduction and esterification of acyl-CoAs of carbon lengths 18-22. High temperature lowered the specificity for elongation of C20-C22 and of C22-C,24 and increased the specificity for reduction of the C20 acid to its corresponding alcohol. The amount of C42 wax ester was greater than would be expected by random association of the alkoxy-acyl groups but this preference was not as great at high temperatures.

scholarly journals Effect of pretreatments on drying behavior of eggplant

2019 ◽  
Vol 17 (1) ◽  
pp. 105-109
Author(s):  
Md Junaeid Khan ◽  
Farjana Yeasmin ◽  
Md Nazrul Islam ◽  
Raju Ahmmed ◽  
Pabitra Chandra Das ◽  
...  
Keyword(s):  
Constant Temperature ◽  
Rate Constant ◽  
Hot Water ◽  
Effect Of Temperature ◽  
Constant Thickness ◽  
Drying Rate ◽  
Fresh Sample ◽  
Drying Time ◽  
Preservation Method ◽  
Drying Behavior

Eggplant is a familiar and admired vegetable in Bangladesh. It is a highly perishable vegetable and cannot be preserved long. Drying is an ancient preservation method used to extend shelf-life of fruits and vegetables. Different Pretreatments may affect the drying kinetics of foods. A study was conducted to evaluate how pretreatments affect the drying behavior of eggplant. Proximate composition of fresh eggplant was analyzed. The samples of constant thickness (8 mm) were dried at 50°C, 55°C and 60°C to determine the effect of temperature on drying rate constant, while for determining the effect of thickness on rate constant, eggplant slices of 4, 6 and 8 mm thicknesses were dried at a constant temperature of 55°C. It was observed that, drying rate decreased with the increase in thickness and the index ‘n’ was found to be 0.89 at 55°C. Under similar drying condition at constant thickness (8 mm), drying time showed an inverse relationship with temperature. The activation energy (Ea) was calculated as 3.242 Kcal/g-mole. Eggplant slices having the highest thickness (8 mm) were blanched at 70°C, 75°C and 80°C for 1, 2 and 2.5 minutes, respectively using hot water bath to determine the effective blanching time and temperature. It was observed that the samples blanched at 75°C and 80°C for 2 minute were enough to inactivate the enzymes. Pretreated (blanched, sulphited and blanched plus sulphited) eggplant slices having constant thickness (8 mm) were dried at constant temperature of 55°C. The drying time was influenced by pretreatments. The highest drying rate was observed for eggplant slices with blanched plus sulphited (5% KMS solution) samples while eggplant slices with 5%KMS solution dipped for 10 minutes showed the lowest drying rate. In case of fresh slices, drying time was lower than blanched and sulphited samples but higher than blanched plus sulphited samples. Pretreatment was also found effective on the color changes (preservation or degradation). Blanching gave a bright color compared to fresh sample but less bright compared to sulphited samples. In case of SO2 retention, blanched plus sulphited sample showed higher retention than sulphited sample. Sulphited sample retains 44.8 ppm SO2/100g of sulphited sample, while the blanched plus sulphited sample retains 280 ppm SO2/100 g of blanched plus sulphited sample. J. Bangladesh Agril. Univ. 17(1): 105–109, March 2019

Effect of Temperature on Response of Tomatoes to Several Dinitroaniline Herbicides and Phosphorus

Weed Science ◽  
1976 ◽  
Vol 24 (1) ◽  
pp. 115-119 ◽  
Author(s):  
H. P. Wilson ◽  
F. B. Stewart ◽  
T. E. Hines
Keyword(s):  
High Temperatures ◽  
Phosphorus Content ◽  
Dry Weight ◽  
Field Studies ◽  
Effect Of Temperature ◽  
Controlled Environment ◽  
Effects Of Temperature ◽  
Environment Chamber ◽  
Chamber Studies ◽  
Dinitroaniline Herbicides

Effects of temperature on response of transplanted tomatoes (Lycopersicon esculentumMill. ‘Campbell 17′) to trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine), nitralin [4-(methylsulfonyl)-2,6-dinitro-N,N-dipropylaniline], profluralin [N-(cyclopropylmethyl)-α,α,α-trifluoro-2,6-dinitro-N-propyl-p-toluidine], and isopropalin (2,6-dinitro-N,N-dipropylcumidine) were investigated in field studies. Trifluralin and nitralin caused greater reductions in growth and yields of tomatoes transplanted early in April than to tomatoes transplanted around May 1. Responses to profluralin were similar but total yields of early transplanted tomatoes were not reduced although initial yields were below those of tomatoes treated with isopropalin. In controlled environment chamber studies, percent phosphorus of plant tops was reduced by trifluralin at low temperatures but was not influenced by trifluralin at high temperatures. Tomoto responses to phosphorus as reflected by plant fresh weight, dry weight and phosphorus content (mg/plant) were reduced by trifluralin at low and high temperatures.

DEVELOPMENTAL TIMES AND FECUNDITY OF IXODES COOKEI PACKARD (ACARI: IXODIDAE) UNDER LABORATORY CONDITIONS

1991 ◽  
Vol 123 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Martha J. Farkas ◽  
Gordon A. Surgeoner
Keyword(s):  
Relative Humidity ◽  
Blood Meal ◽  
Egg Development ◽  
Thermal Threshold ◽  
Egg Hatch ◽  
Marmota Monax ◽  
Complete Development ◽  
Laboratory Conditions ◽  
Adult Females ◽  
Blood Meal Source

AbstractIxodes cookei Packard required ca. 14 weeks to complete development under laboratory conditions, using groundhogs [Marmota monax (L.)] as the blood meal source and off-host conditions of 25–29°C and 93–100% relative humidity. All three post-embryonic instars engorged in ca. 6–8 days. Larvae and nymphs maintained at 25°C moulted to the next instar ca. 18–20 days after detachment. Moult occurred under conditions of either a 0L:24D or a 16L:8D photoperiod. Adult females increased in weight ca. 49-fold from the unfed to the engorged state, attaining a weight of 194.1 ± 15.0 (mean ± SE) mg and producing 1281.5 ± 139.1 (mean ± SE) eggs at 29°C. The pre-ovipositional and ovipositional periods were 4.7 ± 0.3 and 20.2 ± 1.7(mean ± SE) days, respectively, at 29°C. Fifty percent of eggs were deposited within the 1st week of the ovipositional period at 29°C. First egg hatch at 29°C occurred ca. 31 days after oviposition was started. Eggs maintained at 10°C did not hatch, and the thermal threshold for egg development was calculated to be 11.2°C.

The tillering pattern in barley varieties: II. The effect of temperature, light intensity and daylength on the frequency of occurrence of the coleoptile node and second tillers in barley

1969 ◽  
Vol 72 (3) ◽  
pp. 423-435 ◽  
Author(s):  
R. Q. Cannell
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Light Intensity ◽  
Field Experiments ◽  
Tiller Number ◽  
Effect Of Temperature ◽  
Controlled Environment ◽  
Frequency Of Occurrence ◽  
Low Light ◽  
Late Sowing

SUMMARYControlled-environment experiments showed that development of the coleoptile node tiller (T1) was suppressed much more than that of the tiller appearing in the axil of the first true leaf (T2) by high temperature (24/15 °C; 19/10 °C; 10/6 °C), by reduced photoperiod (16 h; 12·5 h) or by low light intensity (1100 ft-c; 1000 ft-c), but minimally in the newest variety, Deba Abed. Unlike previous field experiments, the T1 tiller appeared on more Spratt Archer than Maris Badger plants. Maris Badger plants produced more T1 tillers in a high-low temperature regime (19/10 °C; 10/6 °C) than in continuous low temperature (10/6 °C). In a field experiment T1 tiller number (and yield), but not the number of other major shoots, were severely reduced by late sowing of Spratt Archer, progressively reduced in Maris Badger, but minimally in Deba Abed. This seemed to be associated with higher temperatures at later sowings.

A New Approach about Heat Transfer of Hot-Wire Anemometer

2012 ◽  
Vol 232 ◽  
pp. 747-751 ◽  
Author(s):  
Mojtaba Dehghan Manshadi ◽  
Mohamad Kazemi Esfeh
Keyword(s):  
Heat Transfer ◽  
Ambient Temperature ◽  
Air Flow ◽  
Accurate Method ◽  
Fundamental Principle ◽  
Effect Of Temperature ◽  
Hot Wire ◽  
Temperature Drift ◽  
Flow Temperature ◽  
Temperature Variations

The hot-wire anemometer is a famous thermal transducer for turbulence measurements. The fundamental principle of hot-wire anemometer is based on the convective heat transfer, since the heat transfer is directly proportional to the temperature difference between the sensor and the fluid, hence ambient temperature variations are one of the most important error sources in the measurements with the hot-wire anemometers. Many methods have been proposed to compensate for the ambient temperature variations. In such methods the effect of temperature drift is only considered and the effect of Nusselt number is ignored. In the present research the effect of air flow temperature variations on the response of constant temperature anemometer has been studied experimentally. Furthermore, with the basis of air flow velocity and ambient temperature variations, the percentage errors in velocity measurements have been estimated. Finally, based on achieved results, an accurate method has been proposed to compensate the air flow temperature variations.

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