scholarly journals Determination of Evaporative Fluxes Using a Bench-Scale Atmosphere Simulator

Water ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 84
Author(s):  
Jared Suchan ◽  
Shahid Azam
Keyword(s):  
Accurate Determination ◽  
Test Duration ◽  
Atmospheric Conditions ◽  
Canadian Prairies ◽  
Bench Scale ◽  
Target Values ◽  
Transfer Equations ◽  
Vapour Flux ◽  
Local Water

An accurate determination of evaporative fluxes is critical for efficient water management in semi-arid climates such as in the Canadian Prairies. The main achievements of this research are the design and operation of a bench-scale atmosphere simulator, performance evaluation using selected weather scenarios pertaining to regional atmospheric conditions, validation using established empirical correlations, and estimation of evaporation rates and the amount for a typical local water body. Results indicate that the measured data achieved the target values for the various parameters and the data were found to be stable during the 3-h test duration. The vapour flux was found to have large variation during summer (0.120 g∙s−1∙m−2 during the day and 0.047 g∙s−1∙m−2 at night), low variation during spring (0.116 g∙s−1∙m−2 during the day and 0.062 g∙s−1∙m−2 at night), and negligible change during fall (0.100 g∙s−1∙m−2 during the day and 0.076 g∙s−1∙m−2 at night). The measured vapour flux was generally within one standard deviation of the equality line when compared with that predicted by both the mass-transfer equations and the combination equations. The average evaporation ranged from 4 mm∙d−1 to 8 mm∙d−1 during the day and decreased to 1 mm∙d−1 to 3 mm∙d−1 at night. The 24-h evaporation was found to be 8 ± 1 mm∙d−1 from late April through late October. Likewise, the cumulative annual evaporation was found to be 1781 mm, of which 82% occurs during the day and 18% at night.

scholarly journals Datasets for the Determination of Evaporative Flux from Distilled Water and Saturated Brine Using Bench-Scale Atmospheric Simulators

Data ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. 1
Author(s):  
Jared Suchan ◽  
Shahid Azam
Keyword(s):  
Experimental Data ◽  
Saline Water ◽  
Distilled Water ◽  
Canadian Prairies ◽  
Bench Scale ◽  
Evaporative Flux ◽  
Improved Design ◽  
The Relationship ◽  
Empirical Field

Evaporation from fresh water and saline water is critical for the estimation of water budget in the Canadian Prairies. Predictive models using empirical field-based data are subject to significant errors and uncertainty. Therefore, highly controlled test conditions and accurately measured experimental data are required to understand the relationship between atmospheric variables at water surfaces. This paper provides a comprehensive dataset generated for the determination of evaporative flux from distilled water and saturated brine using the bench-scale atmospheric simulator (BAS) and the subsequently improved design (BAS2). Analyses of the weather scenarios from atmospheric parameters and evaporative flux from the experimental data are provided.

A quantitative approach to inner shell losses

1978 ◽  
Vol 36 (1) ◽  
pp. 526-527 ◽  
Author(s):  
R.D. Leapman ◽  
P. Rez ◽  
D.F. Mayers
Keyword(s):  
Energy Transfer ◽  
Cross Section ◽  
Cross Sections ◽  
Accurate Determination ◽  
Background Intensity ◽  
Core Excitation ◽  
Quantitative Basis ◽  
Cross Section Differential ◽  
Bound Electrons

Microanalysis by EELS has been developing rapidly and though the general form of the spectrum is now understood there is a need to put the technique on a more quantitative basis (1,2). Certain aspects important for microanalysis include: (i) accurate determination of the partial cross sections, σx(α,ΔE) for core excitation when scattering lies inside collection angle a and energy range ΔE above the edge, (ii) behavior of the background intensity due to excitation of less strongly bound electrons, necessary for extrapolation beneath the signal of interest, (iii) departures from the simple hydrogenic K-edge seen in L and M losses, effecting σx and complicating microanalysis. Such problems might be approached empirically but here we describe how computation can elucidate the spectrum shape.The inelastic cross section differential with respect to energy transfer E and momentum transfer q for electrons of energy E0 and velocity v can be written as

Fast calibration of CBED patterns for quantitative analysis

1993 ◽  
Vol 51 ◽  
pp. 674-675
Author(s):  
M.A. Gribelyuk ◽  
M. Rühle
Keyword(s):  
Reciprocal Lattice ◽  
Accurate Determination ◽  
Incident Beam ◽  
Crystal Thickness ◽  
Structure Model ◽  
Beam Direction ◽  
Transmitted Beam ◽  
Reciprocal Vector ◽  
On Line

A new method is suggested for the accurate determination of the incident beam direction K, crystal thickness t and the coordinates of the basic reciprocal lattice vectors V1 and V2 (Fig. 1) of the ZOLZ plans in pixels of the digitized 2-D CBED pattern. For a given structure model and some estimated values Vest and Kest of some point O in the CBED pattern a set of line scans AkBk is chosen so that all the scans are located within CBED disks.The points on line scans AkBk are conjugate to those on A0B0 since they are shifted by the reciprocal vector gk with respect to each other. As many conjugate scans are considered as CBED disks fall into the energy filtered region of the experimental pattern. Electron intensities of the transmitted beam I0 and diffracted beams Igk for all points on conjugate scans are found as a function of crystal thickness t on the basis of the full dynamical calculation.

Computer-Assisted High-Re Solution TEM

1990 ◽  
Vol 48 (1) ◽  
pp. 162-163
Author(s):  
F.A. Ponce ◽  
H. Hikashi
Keyword(s):  
Signal To Noise Ratio ◽  
Accurate Determination ◽  
Computer Software ◽  
Video Camera ◽  
Image Contrast ◽  
Objective Lens ◽  
Computer Assisted ◽  
Optical Parameters ◽  
Astigmatism Correction

The determination of the atomic positions from HRTEM micrographs is only possible if the optical parameters are known to a certain accuracy, and reliable through-focus series are available to match the experimental images with calculated images of possible atomic models. The main limitation in interpreting images at the atomic level is the knowledge of the optical parameters such as beam alignment, astigmatism correction and defocus value. Under ordinary conditions, the uncertainty in these values is sufficiently large to prevent the accurate determination of the atomic positions. Therefore, in order to achieve the resolution power of the microscope (under 0.2nm) it is necessary to take extraordinary measures. The use of on line computers has been proposed [e.g.: 2-5] and used with certain amount of success.We have built a system that can perform operations in the range of one frame stored and analyzed per second. A schematic diagram of the system is shown in figure 1. A JEOL 4000EX microscope equipped with an external computer interface is directly linked to a SUN-3 computer. All electrical parameters in the microscope can be changed via this interface by the use of a set of commands. The image is received from a video camera. A commercial image processor improves the signal-to-noise ratio by recursively averaging with a time constant, usually set at 0.25 sec. The computer software is based on a multi-window system and is entirely mouse-driven. All operations can be performed by clicking the mouse on the appropiate windows and buttons. This capability leads to extreme friendliness, ease of operation, and high operator speeds. Image analysis can be done in various ways. Here, we have measured the image contrast and used it to optimize certain parameters. The system is designed to have instant access to: (a) x- and y- alignment coils, (b) x- and y- astigmatism correction coils, and (c) objective lens current. The algorithm is shown in figure 2. Figure 3 shows an example taken from a thin CdTe crystal. The image contrast is displayed for changing objective lens current (defocus value). The display is calibrated in angstroms. Images are stored on the disk and are accessible by clicking the data points in the graph. Some of the frame-store images are displayed in Fig. 4.

Assessment of Sylphons Lifetime

2008 ◽  
Vol 59 (5) ◽  
pp. 605-610
Author(s):  
Alexandru Pupazescu ◽  
Stefan Minoiu ◽  
Constantin Manea
Keyword(s):  
Elevated Temperature ◽  
Strain Distribution ◽  
Accurate Determination ◽  
Multiaxial Fatigue ◽  
Tensile Curve

The paper contains an assessment of the sylphons lifetime for multiaxial fatigue. Three criteria were used two based on s � N diagram and one based on energy. For a more accurate determination of the sylphons lifetime the stress and the strain distribution been determined using FEM, the tensile curve of the steel W 4541 at elevated temperature.

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