scholarly journals Occurrence of a nearly constant air flux through the accumulation chamber and determination of the two components of the CO2 flux from soil. I: Laboratory experiments.

2018 ◽  
Vol 61 (Vol 61 (2018)) ◽  
Author(s):  
Ana Hernández-Rodríguez ◽  
Giorgio Virgili ◽  
Davide Continanza ◽  
Luca Ferrante
Keyword(s):  
Laboratory Experiments ◽  
Co2 Flux ◽  
Accumulation Chamber

scholarly journals Penentuan Konsentrasi Efektif Ekstrak Tanaman Patikan Kebo (Euphorbia Hirta) Merah Dan Hijau Dalam Melarutkan Kalsium

2018 ◽  
Vol 6 (4) ◽  
pp. 208
Author(s):  
Hamdiana Hamdiana ◽  
Minarni Rama Jura ◽  
Ratman Ratman
Keyword(s):  
Calcium Phosphate ◽  
Kidney Stones ◽  
Laboratory Experiments ◽  
Effective Concentration ◽  
Distilled Water ◽  
Water Determination ◽  
Euphorbia Hirta ◽  
Flame Photometer

The use of traditional materials is one alternative for the treatment of kidney stones. One of them is utilizing a plant of patikan kebo (Euphorbia hirta). This study is conducted by using laboratory experiments and the extract of the plant of patikan kebo red and patikan kebo green to dissolve the calcium phosphate as a substitute for kidney stones. The extraction of samples is conducted by decoction. The aim of the study is to determine the effective concentration of the extracts of patikan kebo red and green to dissolve calcium and test the effectiveness of the extracts of patikan kebo to dissolve calcium compared to Batugin elixir and distilled water. Determination of the concentration of dissolved calcium in the extracts using a flame photometer. The results show that the extract of patikan kebo red with a concentration of 2.1% is effective in dissolve the calcium with a concentration of 5.2 ppm. The extract of patikan kebo green with a concentration of 27.4% is effective in dissolving the calcium with a concentration of 27.5 ppm. When compared with Batugin elixir and distilled water, Batugin elixir can only dissolve the calcium with concentration 15.3 ppm, while distilled water can only dissolve 3 ppm of the calcium.

scholarly journals Determination of the uncertainty of mass flow measurement using the orifice for different values of the Reynolds number

2019 ◽  
Vol 213 ◽  
pp. 02022 ◽  
Author(s):  
Anna Golijanek-Jędrzejczyk ◽  
Andrzej Mrowiec ◽  
Robert Hanus ◽  
Marcin Zych ◽  
Dariusz Świsulski
Keyword(s):  
Reynolds Number ◽  
Mass Flow ◽  
Flow Measurement ◽  
Laboratory Experiments ◽  
Energy Industry ◽  
Maximum Difference ◽  
Know How ◽  
Simulation And Experiment ◽  
Extended Uncertainty

Standard orifice flowmeters are widely used in the chemical and energy industry. Therefore, it is essential to know how accurate the measurements made with these instruments are. The paper presents an estimation of measurement uncertainty of a liquid mass flow using the orifice plate. The authors will present the influence of ranges of the Reynolds number on the estimated uncertainty, obtained on the basis of simulation and laboratory experiments. The research was conducted for the central orifice in the Reynolds number 8,000 < Re < 21,000. The results of estimating the extended uncertainty of the measurement of water flow using simulation and experimental method, are convergent. The maximum difference in the extended uncertainty values of flow measurement for the simulation and experiment was 0.04.10-3 kg/s.

scholarly journals A17-year dataset of surface water fugacity of CO<sub>2</sub>, along with calculated pH, Aragonite saturation state, and air-sea CO<sub>2</sub> fluxes in the Northern Caribbean Sea

2020 ◽  
Author(s):  
Rik Wanninkhof ◽  
Denis Pierrot ◽  
Kevin Sullivan ◽  
Leticia Barbero ◽  
joaquin Trinanes
Keyword(s):  
Surface Water ◽  
Co2 Flux ◽  
Caribbean Sea ◽  
Total Alkalinity ◽  
Saturation State ◽  
Aragonite Saturation ◽  
Cruise Ships ◽  
Water Fugacity ◽  
Ground Truthing

Abstract. A high-quality dataset of surface water partial pressure/fugacity of CO2 (pCO2w/fCO2w), comprised of over a million observations, and derived products are presented for the Caribbean Sea covering the timespan from 2002 through 2018. Prior to installation of automated pCO2 systems on cruise ships of the Royal Caribbean Cruise Lines and subsidiaries, very limited surface water carbon data were available in this region. With this observational program, the Northern Caribbean Sea has now become one of the best sampled regions for pCO2 of the world's ocean. The dataset, and derived quantities are provided on a 1-degree monthly grid at http://accession.nodc.noaa.gov/0207749, DOI: https://doi.org/10.25921/2swk-9w56 (Wanninkhof et al., 2019a). The derived quantities include total alkalinity (TA), acidity (pH), Aragonite saturation state (ΩAr) and air-sea CO2 flux, and cover the region from 15° N to 28° N and 88° W to 62° W. The data and products are used for determination of status and trends of ocean acidification, for quantifying air-sea CO2 fluxes, and for ground truthing models. Methodologies to derive the inorganic carbon system parameters and to calculate the fluxes from fCO2w are described.

scholarly journals Properties and cleanability of new and traditional surface materials in cattle barns - a field study

2008 ◽  
Vol 17 (3) ◽  
pp. 227 ◽  
Author(s):  
R. KUISMA ◽  
H-R. KYMÄLÄINEN ◽  
M. HELLSTEDT
Keyword(s):  
Field Study ◽  
Laboratory Experiments ◽  
Laboratory Studies ◽  
Surface Materials ◽  
Colour Changes ◽  
The Difference ◽  
Coated Surfaces ◽  
One Year ◽  
The One

In this study surface properties and cleanability of new and traditional surface materials in cattle barns were examined in a field test. The concrete and plastic-coated samples were placed on a walking path on the floor and on a feeding table in a cattle barn. The surfaces were characterized using colorimetric and gloss measurements and determination of topography. In most cases, the colour of the surfaces placed on the floor darkened during the one year study period, whereas the colour changes of the samples placed on the feeding table did not show a similar trend. However, in both locations the plastic-coated surfaces were generally the easiest to clean, and the highest colour changes indicating soil residues were detected on the uncoated and silane-impregnated concrete surfaces. The difference between the locations was also seen in the gloss values, which increased in the samples placed on the floor during the one-year test period but varied considerably between the different materials on the surfaces placed on the feeding table. This field study confirmed the observation from earlier laboratory studies that plastic coatings improved the cleanability of concrete cattle barn surfaces. Silane impregnation was not functionally competitive with the plastic coatings. In general, the cleanability results were in accordance with the results of previous laboratory experiments but the field study provided practical information about the behaviour of the surface materials examined.;

scholarly journals Manning's roughness coefficient determination in laboratory experiments using 2D modeling and automatic calibration

2020 ◽  
pp. 22-33
Author(s):  
Basile Lavoie ◽  
Tew-Fik Mahdi
Keyword(s):  
Experimental Data ◽  
Laboratory Experiments ◽  
Numerical Models ◽  
Roughness Coefficient ◽  
Automatic Calibration ◽  
Test Cases ◽  
Data Sets ◽  
Step Method ◽  
Numerous Data

Reliable experimental data are essential for choosing and validating numerical models. Although numerous data sets have been presented in the literature, few have been made widely available to the scientific community. Additionally, these experimental data sets have generally given little attention to the determination of Manning's roughness coefficients. This paper addresses these two issues. Three channel configurations are studied: a flatbed channel, a channel with a triangular sill and a channel with a triangular abutment. Three increasing permanent discharges are used for each configuration, leading to nine test cases. The Manning's coefficients are determined using three methods: the traditional step method, automatic calibration, via a 2D hydrodynamic model, considering theoretical value intervals and automatic calibration ignoring these intervals. The results show that automatic calibration with theoretical value intervals is advantageous compared to the step method. Automatic calibration ignoring theoretical intervals yields low errors but unphysical values; therefore, it is not recommended.

scholarly journals Comparison of Hydraulic Conductivity Values Obtained from Empirical Formulae and Laboratory Experiments

2020 ◽  
Vol 68 (4) ◽  
pp. 669-678
Author(s):  
Mario Hala ◽  
Lubomír Petrula ◽  
Zakaraya Alhasan
Keyword(s):  
Experimental Data ◽  
Hydraulic Conductivity ◽  
Laboratory Experiments ◽  
Internal Erosion ◽  
Variable Porosity ◽  
Groundwater Flow Regime ◽  
Series Of Experiments ◽  
Different Grain Size ◽  
Good Agreement

Hydraulic conductivity determination plays an essential role in the investigation of groundwater flow regime which can then influence many field problems such as pumping capabilities in the area, transport of contaminant or heat and soil internal erosion. Numerous equations based on dimensional analysis or experimental measurements have been published since the end of the 19th century for the determination of hydraulic conductivity. However, not all of these formulae are applicable for every material and all of them bring some uncertainty in the value of hydraulic conductivity. This paper contains a description of experimental research carried out concerning the determination of hydraulic conductivity for four types of sand with different grain size distribution curves and variable porosity. Obtained values of hydraulic conductivity ranged from 1 × 10-4 to 4 × 10-3 according to the sample porosity. The series of experiments consisted of 160 separate tests conducted in order to obtain relevant statistical sets. In this paper, the experimental data are discussed and compared with hydraulic conductivities obtained from 6 empirical formulae recommended in a previous study. The comparison showed that some empirical formulae provide a good agreement with the experimental data (the most precise were formulae published by Terzaghi and by Sauerbrey). However, some formulae showed high deviation from measured data (formula published by Zamarin).

DETERMINATION OF BIOLOGICAL VALUES AND TOXICO-BIOLOGICAL INDICATORS OF PRODUCTS OF SLAUGHTER OF PIGS AT ASCARIASIS

2019 ◽  
Vol 1 (4) ◽  
pp. 370-374
Author(s):  
I.S. Osipova ◽  
◽  
M.P. Butko ◽  
P.А. Popov ◽  
◽  
...  
Keyword(s):  
Laboratory Experiments ◽  
Federal District ◽  
Tetrahymena Pyriformis ◽  
Biological Indicators ◽  
Express Method ◽  
Test Culture ◽  
Comparative Aspect ◽  
The Russian Federation ◽  
Method Of Assessment

Among helminthic diseases the greatest distribution in the territory of the Russian Federation, especially in the Central Federal district, in private farmsteads, acquired ascariasis of pigs. The article presents the results of laboratory experiments on determining the biological value and possible toxicity of the meat of pigs, Ascaris invested by the express method of assessment toxic-biological indicators using the test-culture Tetrahymena pyriformis (strain WH14 ) in the comparative aspect of the degree of infestation.

A METHOD FOR THE DETERMINATION OF THE KINETIC FRICTION COEFFICIENT IN FRICTION PAIRS BASED ON DIRECT ACCELERATION MEASUREMENT OF AN OBJECT ON AN INCLINED PLANE

Tribologia ◽  
2019 ◽  
Vol 284 (2) ◽  
pp. 57-64
Author(s):  
Wacław Gawędzki ◽  
Mirosław Socha
Keyword(s):  
Friction Coefficient ◽  
Measurement Errors ◽  
Laboratory Experiments ◽  
Kinetic Friction ◽  
Test Rig ◽  
Inclined Plane ◽  
Acceleration Measurement ◽  
Steel Cast ◽  
Theoretical Foundations

The paper presents and experimentally verifies a method for the determination of the kinetic friction coefficient of friction pairs. The method involves a direct acceleration measurement of an object sliding down an inclined plane and the determination of the momentary friction force based on acceleration. The laboratory test rig was presented and the theoretical foundations of the method were discussed in detail. The laboratory experiments were conducted for the following material pairs: steel-cast iron, steel-bronze, and for various inclined plane angles. The experiments results were presented, acceleration vs. time curves were plotted, and friction coefficients were determined. These values were compared to the values known from literature [L. 1–3]. The uncertainly analysis of kinetic friction coefficient determination was conducted. The method effectiveness and accuracy was verified, noting the sources of possible measurement errors and the ways to eliminate them.

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