Temperature and Moisture Gradients under Low Stratus Clouds*

1952 ◽  
Vol 33 (10) ◽  
pp. 403-408 ◽  
Author(s):  
Peter E. Kraght
Keyword(s):  
Steady State ◽  
Water Vapor ◽  
Equilibrium State ◽  
Dew Point ◽  
Lapse Rate ◽  
Stratus Clouds ◽  
A Value ◽  
Statistical Sample

The lapse rate of dew point is developed from thermodynamic relations. It is shown to have varied values depending on the flux of water vapor but to have a value of nearly 1.0F° per 1,000 feet for steady state. The lapse rate of temperature is developed after a method suggested by Priestley and Swinbank. Approximately 10,000 cases of ceiling heights, temperatures and dew points observed simultaneously are used as a statistical sample to represent an equilibrium state for a layer 1,000 feet or less thick. The results suggest the ratio of the equilibrium lapse rate to the dry adiabatic lapse rate is nearly 0.80.

A System for Individualized Dosing of Intravenous Aminophylline Using a Programmable Calculator

PEDIATRICS ◽  
1984 ◽  
Vol 73 (1) ◽  
pp. 64-67
Author(s):  
J. Chris Mitsuoka ◽  
Richard J. Fleck
Keyword(s):  
Steady State ◽  
Serum Sample ◽  
Drug Exposure ◽  
Plasma Concentrations ◽  
Dose Administration ◽  
Programmable Calculator ◽  
Concentration Determination ◽  
A Value ◽  
Individualized Dosing ◽  
History Of

A program that calculates a value of clearance for an individual patient prior to reaching steady state in the early stages of aminophylline therapy is presented. The program is written for the Texas Instruments TI-59 programmable calculator and may be used with or without the PC-100C printer. The program can provide clinically useful information concerning projected plasma concentrations prior to reaching steady state with an accurate history of the dose administration and serum concentration determination. If the patient has not received xanthene therapy prior to admission, only one serum sample is required. If there has been prior drug exposure, a second serum sample is required. An iterative technique, which would be impractical to use without calculator assistance, is employed to make these determinations.

Super-Fine Structure in the Critical Flow-Rate of Critical Flow Venturi Nozzles

2002 ◽  
Author(s):  
Masahiro Ishibashi
Keyword(s):  
Fine Structure ◽  
Steady State ◽  
Discharge Coefficient ◽  
Constant Pressure ◽  
Pressure Ratio ◽  
Critical Flow ◽  
Time Intervals ◽  
Critical Flow Rate ◽  
A Value ◽  
Long Time

It is shown that critical flow Venturi nozzles need time intervals, i.e., more than five hours, to achieve steady state conditions. During these intervals, the discharge coefficient varies gradually to reach a value inherent to the pressure ratio applied. When a nozzle is suddenly put in the critical condition, its discharge coefficient is trapped at a certain value then afterwards approaches gradually to the inherent value. Primary calibrations are considered to have measured the trapped discharge coefficient, whereas nozzles in applications, where a constant pressure ratio is applied for a long time, have a discharge coefficient inherent to the pressure ratio; inherent and trapped coefficients can differ by 0.03–0.04%.

Kinetics of the hydrolysis of cellobiose and p-nitrophenyl-β-D-glucoside by cellobiase of Trichoderma viride

1977 ◽  
Vol 55 (1) ◽  
pp. 19-26 ◽  
Author(s):  
R. James Maguire
Keyword(s):  
Steady State ◽  
Trichoderma Viride ◽  
Solution Temperature ◽  
Temperature Range ◽  
A Value ◽  
Steady State Kinetics ◽  
Decreasing Ph ◽  
Ph Curve ◽  
Kinetics Of ◽  
Hydrolysis Of

Cellobiase has been isolated from the crude cellulase mixture of enzymes of Trichoderma viride using column chromatographic and ion-exchange methods. The steady-state kinetics of the hydrolysis of cellobiose have been investigated as a function of cellobiose and glucose concentrations, pH of the solution, temperature, and dielectric constant, using isopropanol–buffer mixtures. The results show that (i) there is a marked activation of the reaction by initial glucose concentrations of 4 × 10−3 M to 9 × 10−2 M and strong inhibition of the reaction at higher initial concentrations, (ii) the log rate – pH curve has a maximum at pH 5.2 and enzyme pK values of 3.5 and 6.8, (iii) the energy of activation at pH 5.1 is 10.2 kcal mol−1 over the temperature range 5–56 °C, and (iv) the rate decreases from 0 to 20% (v/v) isopropanol.The hydrolysis by cellobiase (EC 3.2.1.21) of p-nitrophenyl-β-D-glucoside was examined by pre-steady-state methods in which [Formula: see text], and by steady-state methods as a function of pH and temperature. The results show (i) a value for k2 of 21 s−1 at pH 7.0 (where k2 is the rate constant for the second step in the assumed two-intermediate mechanism [Formula: see text]) (ii) a log rate–pH curve, significantly different from that for hydrolysis of cellobiose, in which the rate increases with decreasing pH below pH 4.5, is constant in the region pH 4.5–6, and decreases above pH 6 (exhibiting an enzyme pK value of 7.3), and (iii) an activation energy of 12.5 kcal mol−1 at pH 5.7 over the temperature range 10–60 °C.

Heat and Mass Transfer in Double-Filmwise Heat Exchanger for Industrial Food Processing Applications

2011 ◽  
Author(s):  
Helen Skop ◽  
James Pezzuto ◽  
Valeriy G. Oleynikov-White ◽  
John F. Cavallo ◽  
Robert Fesjian
Keyword(s):  
Water Vapor ◽  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Waste Heat ◽  
Cost Effective ◽  
Dew Point ◽  
Point Temperature ◽  
Dew Point Temperature ◽  
Gas Cooling ◽  
Stack Gas

The baking industry is considered as one of the major energy consuming food industries in North America. More than 40% of bakery fuel consumption is used to evaporate water in the processes [1]. In addition to the baking process’ vapor the oven stack gas contains water vapor from combustion products. Overall the content of water vapor in the typical oven stack gas is about 20% by volume. Most bakeries waste this vapor and its latent heat. Bakeries’ ovens have wide diversity in power and design. Off-the-shelve heat exchangers are not considered as cost effective equipment for stack gas cooling below gas’ dew point temperature. At typical oven stack gas composition water vapor condensation begins to condense at about 72° C. Not using the latent heat of stack water vapor and the heat from gas cooling from dew point temperature to ambient temperature results in low effectiveness of waste heat recovery. Mainly the effect from the recovery of stack gas cooling prior to condensation is considered as non cost effective and waste heat recovery is neglected.

Coupling and Cooperative Up-conversion Coefficients in Er-doped Si Nanocrystals

2003 ◽  
Vol 770 ◽  
Author(s):  
Domenico Pacifici ◽  
Giorgia Franzò ◽  
Fabio Iacona ◽  
Francesco Priolo
Keyword(s):  
Steady State ◽  
Energy Level ◽  
Energy Level Scheme ◽  
Time Resolved ◽  
A Value ◽  
Si Nanocrystals ◽  
Si Nanocrystal ◽  
Conversion Coefficients ◽  
Quantitative Understanding ◽  
Er Doped

AbstractIn the present work, a quantitative understanding of the Er-doped Si nanocrystals interaction is reported. We present a model based on an energy level scheme taking into account the coupling between each Si nanocrystal and the neighboring Er ions. By fitting the steady state and time resolved luminescence signals at both the 1.54 and 0.98 μm Er lines we were able to determine a value of 3×10-15 cm3 s-1 for the coupling coefficient. Moreover, a strong cooperative up-conversion mechanism, active between two excited Er ions and characterized by a coefficient of 7×10-17 cm3 s-1, will be shown to be active in the system, demonstrating that each Si nanocrystal can actually excite more than one Er ion.

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