A RAPID GRAPHICAL METHOD FOR THE INTERPRETATION OF A‐ AND H‐TYPE ELECTRICAL SOUNDINGS

Geophysics ◽  
1968 ◽  
Vol 33 (5) ◽  
pp. 822-833 ◽  
Author(s):  
Adel A. R. Zohdy

Three‐layer vertical electrical sounding (VES) curves that register the effect of a highly resistive electric basement are of either the minimum (H) or the double‐ascending (A) type. The correct interpretation of these two important types of VES curves depends largely on the successful determination of the resistivity of the second layer. This resistivity can sometimes be evaluated from electric logs, from a comparative study of field VES curves, from electrical measurements on outcrops, or from parametric VES curves. A new single auxiliary curve has been devised to help interpret both these types of VES curves, provided that the resistivity of the second layer is known. The thickness of the middle layer is determined accurately and rapidly by the value of the abscissa at the intersection of the total longitudinal conductance line S with the new auxiliary curve. The auxiliary curve is used to interpret an H‐type curve, an A‐type curve, and a five‐layer (KQH‐type) parametric VES curve. Analysis of the KQH parametric curve shows that the resistivity of the third layer may vary by more than a thousandfold without affecting the shape of the curve, whereas the resistivities of the second and fourth layers may correspondingly vary by less than one order of magnitude.

Geophysics ◽  
1975 ◽  
Vol 40 (1) ◽  
pp. 121-122 ◽  
Author(s):  
Sri Niwas

In a recent paper Lee and Green (1973) worked out a method for direct interpretation of electrical soundings made over a fault or dike (see Figure 1). They computed the kernel function using the method developed by Meinardus (1970). However, Koefoed (1968), while dealing with direct interpretation of electrical measurements made over a horizontally layered earth, showed that the relative variations in the apparent resistivity were not of the same order of magnitude in the corresponding kernel curve; thus, any method based on the determination of this function as the intermediate step would lead to a loss of information and hence to incorrect interpretation. Koefoed (1970) introduced a function T(λ) called the resistivity transform (a function related to the kernel function) as an intermediate step. Ghosh (1971) used linear filter theory and gave a simple and quick procedure to obtain the T(λ) function from the apparent resistivity field curve. He cited the properties of the T function as, (1) it is solely determined by the layer distribution; (2) it is an unambiguous representation of the [Formula: see text] function; and (3) for small and large values of 1/λ it approaches the [Formula: see text] curves.


2019 ◽  
Vol 7 (2A) ◽  
Author(s):  
Camilo Fuentes Serrano ◽  
Juan Reinaldo Estevez Alvares ◽  
Alfredo Montero Alvarez ◽  
Ivan Pupo Gonzales ◽  
Zahily Herrero Fernandez ◽  
...  

A method for determination of Cr, Fe, Co, Ni, Cu, Zn, Hg and Pb in waters by Energy Dispersive X Ray Fluorescence (EDXRF) was implemented, using a radioisotopic source of 238Pu. For previous concentration was employed a procedure including a coprecipitation step with ammonium pyrrolidinedithiocarbamate (APDC) as quelant agent, the separation of the phases by filtration, the measurement of filter by EDXRF and quantification by a thin layer absolute method. Sensitivity curves for K and L lines were obtained respectively. The sensitivity for most elements was greater by an order of magnitude in the case of measurement with a source of 238Pu instead of 109Cd, which means a considerable decrease in measurement times. The influence of the concentration in the precipitation efficiency was evaluated for each element. In all cases the recoveries are close to 100%, for this reason it can be affirmed that the method of determination of the studied elements is quantitative. Metrological parameters of the method such as trueness, precision, detection limit and uncertainty were calculated. A procedure to calculate the uncertainty of the method was elaborated; the most significant source of uncertainty for the thin layer EDXRF method is associated with the determination of instrumental sensitivities. The error associated with the determination, expressed as expanded uncertainty (in %), varied from 15.4% for low element concentrations (2.5-5 μg/L) to 5.4% for the higher concentration range (20-25 μg/L).


1996 ◽  
Vol 27 (4) ◽  
pp. 247-254 ◽  
Author(s):  
Zekâi Şen

A simple, approximate but practical graphical method is proposed for estimating the storage coefficient independently from the transmissivity value, provided that quasi-steady state flow data are available from a pumping test. In the past, quasi-steady state flow distance-drawdown data have been used for the determination of transmissivity only. The method is applicable to confined and leaky aquifers. The application of the method has been performed for various aquifer test data available in the groundwater literature. The results are within the practical limits of approximation compared with the unsteady state flow solutions.


Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1238
Author(s):  
Eduardo Laga ◽  
David Dalmau ◽  
Sofía Arregui ◽  
Olga Crespo ◽  
Ana I. Jimenez ◽  
...  

The goal of the work reported here was to amplify the fluorescent properties of 4-aryliden-5(4H)-oxazolones by suppression of the hula-twist non-radiative deactivation pathway. This aim was achieved by simultaneous bonding of a Pd center to the N atom of the heterocycle and the ortho carbon of the arylidene ring. Two different 4-((Z)-arylidene)-2-((E)-styryl)-5(4H)-oxazolones, the structures of which are closely related to the chromophore of the Kaede protein and substituted at the 2- and 4-positions of the arylidene ring (1a OMe; 1b F), were used as starting materials. Oxazolones 1a and 1b were reacted with Pd(OAc)2 to give the corresponding dinuclear orthometalated palladium derivates 2a and 2b by regioselective C–H activation of the ortho-position of the arylidene ring. Reaction of 2a (2b) with LiCl promoted the metathesis of the bridging carboxylate by chloride ligands to afford dinuclear 3a (3b). Mononuclear complexes containing the orthopalladated oxazolone and a variety of ancillary ligands (acetylacetonate (4a, 4b), hydroxyquinolinate (5a), aminoquinoline (6a), bipyridine (7a), phenanthroline (8a)) were prepared from 3a or 3b through metathesis of anionic ligands or substitution of neutral weakly bonded ligands. All species were fully characterized and the X-ray determination of the molecular structure of 7a was carried out. This structure has strongly distorted ligands due to intramolecular interactions. Fluorescence measurements showed an increase in the quantum yield (QY) by up to one order of magnitude on comparing the free oxazolone (QY < 1%) with the palladated oxazolone (QY = 12% for 6a). This fact shows that the coordination of the oxazolone to the palladium efficiently suppresses the hula-twist deactivation pathway.


1979 ◽  
Vol 179 (3) ◽  
pp. 697-700 ◽  
Author(s):  
N Gains

By using a standard graphical method values of Km and V may be found that are independent of the conditions and assumptions that the total substrate concentration approximates to its free concentration and that Km is much larger than the enzyme concentration. The procedure is also applicable to the determination of equilibrium binding parameters of a ligand to a macromolecule.


1997 ◽  
Vol 12 (11) ◽  
pp. 1967-1974 ◽  
Author(s):  
Kazuaki Kuroda ◽  
Mark A. Barton ◽  
Atsushi Onae ◽  
Yukinobu Miki

We propose the application of a new technique, the X pendulum, to determine the Newtonian gravitational constant G. We evaluate the likely experimental errors for configurations realizable with existing technologies and show that improvement of the accuracy by an order of magnitude or more is possible.


2021 ◽  
Author(s):  
Larisa A. Chipiga ◽  
Anna E. Petrova ◽  
Artem A. Mosunov ◽  
Laura T. Naurzbaeva ◽  
Stanislaus M. Kushnarenko ◽  
...  

In connection with the constantly increasing use of monoclonal antibodies labeled with 89Zr, in clinical practice, it is urgent to study their pharmacokinetics with the determination, based on the data obtained, of absorbed doses in tumor foci, as well as intact organs and tissues, and effective doses of patients. To date, there are a limited number of studies that provide patient doses for diagnostic examinations using 89Zr-labeled monoclonal antibodies. In this regard, the purpose of this work was to assess the biodistribution of various monoclonal antibodies (ramucirumab, trastuzumab, atezolizumab) labeled with 89Zr, based on published data, with subsequent calculation of absorbed doses in radiosensitive organs and tissues and effective doses of patients. Based on the analysis of experimental data on the biodistribution of monoclonal antibodies labeled with 89Zr for the diagnosis of oncological diseases from the available literature sources and our own assessments, it has been concluded that the results of the determination of absorbed in organs and tissues and effective doses are inconsistent. The absorbed doses in organs, according to different literature sources, vary up to an order of magnitude within one organ and reach 440 mGy per examination, the effective dose varies from 3 to 112 mSv per examination. This may be due to differences in study design, radiometry and dose assessment methods. Comparison with doses obtained on the basis of a general model of biodistribution of monoclonal antibodies demonstrates the possibility of using this model for a rough estimate of internal doses of patients. However, for a more accurate assessment, it is necessary to standardize approaches to the determination of internal radiation doses using the most effective methodological solutions and software products.


2021 ◽  
Vol 4 (4) ◽  
pp. 547-560
Author(s):  
Aniefiok Akpaneno ◽  
S. Abdulwahab

A geophysical investigation involving Vertical Electrical Sounding (VES) using the Schlumberger array was carried out at the Isa Kaita College of Education specifically at the Male Hostel. The aim of the investigation is to explore the groundwater contamination of the area with the objectives: to determine the depth to basement of the study area, to determine the aquifer thickness, to determine the depth to aquifer, to determine the conductivity of the aquifer and to determine the thickness of topsoil and its variation in resistivity. A total of four (4) vertical electrical soundings were carried out using Schlumberger configuration. Terrameter signal averaging system (SAS) model 300 was the instrument used. The survey area is dominated by mainly four layers, namely: Topsoil, Weathered basement, fractured basement. The value of VES 03 and VES 04 have high electrical conductivities which likely shows they are contaminated, The topsoil resistivity along the profile ranges from approximately 1 to 154, The depth to basement (basement topography) Varies from 4.94 m to 7.59 m, The thickness of aquifer range from  1 m to 6.8 m.  Therefore VES 02 has high Potential for groundwater because it has retaining capacity and good aquifer thickness and is therefore recommended for borehole establishment. It is recommended that the management of Isa Kaita College of Education should provide a concrete dumping site to avoid leaching of waste in ground thereby contaminating the groundwater.


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