DETERMINATION OF TOTAL ORGANIC PHOSPHORUS IN SOILS BY EXTRACTION METHODS

1963 ◽  
Vol 43 (1) ◽  
pp. 35-43 ◽  
Author(s):  
J. F. Dormaar ◽  
G. R. Webster
Keyword(s):  
Organic Solvents ◽  
Hydrofluoric Acid ◽  
Organic Phosphorus ◽  
Extraction Methods ◽  
The Other ◽  
Blue Color ◽  
Cent Level ◽  
Analytical Time ◽  
Selection Of

Comparisons were made between the quantities of organic phosphorus extracted from some Alberta soils by the Kaila-Virtanen method (10), an expanded Kaila-Virtanen procedure, and the Mehta et al. method (15). The modifications for the Kaila-Virtanen method were introduced as a result of the present study.One of the main difficulties encountered in the expanded procedure was the selection of organic solvents that would not interfere with the molybdophosphoric blue color reaction. The non-interfering acetone and acetone containing 0.2 M acetyl acetone gave increased extraction of organic phosphorus from the surface and B horizon samples, respectively. Hydrofluoric acid was recommended for B horizon samples.The expanded Kaila-Virtanen procedure extracted significantly more organic phosphorus (at 5 per cent level) than either of the other methods. The expanded Kaila-Virtanen method does not require more analytical time than the original. Furthermore, as a result of a larger number of extractions involved, this expanded procedure should have an advantage over the other two for studying the various forms of organic phosphorus extracted.

scholarly journals Two particle picking procedures for filamentous proteins: SPHIRE-crYOLO filament mode and SPHIRE-STRIPER

2020 ◽  
Author(s):  
Thorsten Wagner ◽  
Luca Lusnig ◽  
Sabrina Pospich ◽  
Markus Stabrin ◽  
Fabian Schönfeld ◽  
...  
Keyword(s):  
Neural Network ◽  
Deep Neural Network ◽  
Molecular Complexes ◽  
High Accuracy ◽  
The Other ◽  
Line Detection ◽  
Data Sets ◽  
Detection Approach ◽  
Selection Of

AbstractStructure determination of filamentous molecular complexes involves the selection of filaments from cryo-EM micrographs. The automatic selection of helical specimens is particularly difficult and thus many challenging samples with issues such as contamination or aggregation are still manually picked. Here we present two approaches for selecting filamentous complexes: one uses a trained deep neural network to identify the filaments and is integrated in SPHIRE-crYOLO, the other one, called SPHIRE-STRIPER, is based on a classical line detection approach. The advantage of the crYOLO based procedure is that it accurately performs on very challenging data sets and selects filaments with high accuracy. Although STRIPER is less precise, the user benefits from less intervention, since in contrast to crYOLO, STRIPER does not require training. We evaluate the performance of both procedures on tobacco mosaic virus and filamentous F-actin data sets to demonstrate the robustness of each method.

scholarly journals Penerapan Metode SAW dan Fuzzy Dalam Sistem Pendukung Keputusan Penerimaan Beasiswa

2016 ◽  
Vol 3 (2) ◽  
pp. 89 ◽  
Author(s):  
Risa Helilintar ◽  
Wing Wahyu Winarno ◽  
Hanif Al Fatta
Keyword(s):  
Decision Making ◽  
Decision Support ◽  
The Other ◽  
Decision Making Process ◽  
Study Program ◽  
Fuzzy Database ◽  
The University ◽  
To Receive ◽  
Selection Of

Database Model Fuzzy Tahani dan SAW merupakan saatu metode yang dapat digunakan pada proses pengambilan keputusan. Sesuai dengan peraturan pihak Intansi yang memberikan beasiswa unuk memperoleh beasiswa, maka diperlukan kriteria-kriteria untuk menentukan siapa yang akan terpilih untuk menerima beasiswa. Pembagian beasiswa dilakukan untuk membantu penentuan dalam merekomendasikan seseorang yang layak menerima beasiswa maka dibutuhkan sistem pendukung keputusan. Penelitian ini membahas tentang seleksi penerimaan beasiswa dengan metode Fuzzy Database Tahani dan SAW. Penelitian ini dapat membantu KaProdi Teknik Informatika maupun Prodi-Prodi lain di UNP kediri untuk menentukkan penerima beasiswa. Penelitian ini bertujuan untuk memadukan metode Fuzzy dan SAW dengan ketentuan dan kriteria yang sudah ditentukan oleh pihak Universitas. Sistem yang akan dibuat harus mampu menentukan perangkingan untuk rekomendasi penerima beasiswa. Penelitian menggunakan metode fuzzy yaitu untuk menentukan nilai input ke SAW sebagai dasar nilai input. Hasil yang didapat pada penelitian ini yaitu berupa rangking dan selanjutnya akan dibuat rekomendasi untuk penerima beasiswa.Database fuzzy Tahani and SAW is the other, a method that can be used in the decision making process. In accordance with the regulation which provides scholarships instance transform and obtaining scholarships, the necessary criteria to determine who will be selected to receive a scholarship. The scholarship division. To assist in the determination of a person recommend the eligible then takes a decision support system. This study discusses the selection of scholarship acceptance by Fuzzy Database Tahani and SAW. This research can help leadership courses Informatics and other study program-UNP Kediri to determine recipients. This research aims to integrate Fuzzy and SAW with the rules and criteria set by the university. The system being designed to be able to determine rankings to recommendation recipients. Research using fuzzy method is to determine the value of the input to the SAW as the basis of input values. The results obtained in this study in the form of ranking and then make a recommendation to the receiving scholarships

Selection of Adsorbents and Determination of Parameters for the Separation of Glucose, Fructose, Sucrose and Fructooligosaccharides

2010 ◽  
Vol 6 (6) ◽  
Author(s):  
Raquel Cristine Kuhn ◽  
Francisco Maugeri Filho
Keyword(s):  
Experimental Data ◽  
Active Carbon ◽  
The Other ◽  
Isothermal Kinetics ◽  
Nax Zeolite ◽  
Selection Step ◽  
Determination Of Parameters ◽  
Best Fit ◽  
Selection Of

This work aimed to describe the adsorption of sugars (glucose, fructose, sucrose and fructooligosaccharides) employing different adsorbents (celite, active carbon and NaX zeolite) by means of isothermal models. At the adsorbent selection step, the active carbon exhibited a higher affinity for the adsorption of fructooligosaccharides. On the other hand, the adsorbents NaX zeolite and celite presented the highest adsorption stability with glucose, giving values of 1.496 g glucose/g zeolite and 1.35 g glucose/g celite. Therefore, zeolite and celite were the adsorbents selected for the determination of isothermal kinetics and it was shown that the linear model (q*= k.C*) provided the best fit for the experimental data. The temperatures studied were 30, 40 and 50 °C, and the 50°C resulted in the highest partition coefficient (k) for glucose on celite, indicating that higher temperatures benefit sugar adsorption.

scholarly journals Two particle-picking procedures for filamentous proteins: SPHIRE-crYOLO filament mode and SPHIRE-STRIPER

2020 ◽  
Vol 76 (7) ◽  
pp. 613-620
Author(s):  
Thorsten Wagner ◽  
Luca Lusnig ◽  
Sabrina Pospich ◽  
Markus Stabrin ◽  
Fabian Schönfeld ◽  
...  
Keyword(s):  
Neural Network ◽  
Deep Neural Network ◽  
Molecular Complexes ◽  
High Accuracy ◽  
The Other ◽  
Line Detection ◽  
Data Sets ◽  
Detection Approach ◽  
Selection Of

Structure determination of filamentous molecular complexes involves the selection of filaments from cryo-EM micrographs. The automatic selection of helical specimens is particularly difficult, and thus many challenging samples with issues such as contamination or aggregation are still manually picked. Here, two approaches for selecting filamentous complexes are presented: one uses a trained deep neural network to identify the filaments and is integrated in SPHIRE-crYOLO, while the other, called SPHIRE-STRIPER, is based on a classical line-detection approach. The advantage of the crYOLO-based procedure is that it performs accurately on very challenging data sets and selects filaments with high accuracy. Although STRIPER is less precise, the user benefits from less intervention, since in contrast to crYOLO, STRIPER does not require training. The performance of both procedures on Tobacco mosaic virus and filamentous F-actin data sets is described to demonstrate the robustness of each method.

scholarly journals The application of different methods for the determination of fat content in selected animal - origin products

2011 ◽  
Vol 27 (4) ◽  
pp. 1851-1852
Author(s):  
M. Surma-Zadora ◽  
K. Topolska ◽  
E. Cieślik ◽  
K. Sieja
Keyword(s):  
Soxhlet Extraction ◽  
Food Product ◽  
Extraction Methods ◽  
Fat Content ◽  
The Other ◽  
Animal Origin ◽  
Intermediate Precision ◽  
Food Composition Tables ◽  
Validation Parameters

The aim of the study was to assess the fat content in selected animal-origin products (ie. black pudding, luncheon, wiener, bacon) as well as certified reference material (MUVA RM700 Boiled Sausage) using two analytical methods. One of them was the fat extraction using a Soxhlet technique, and the other one - the extraction using carbon dioxide in supercritical state. Methods based on Soxhlet extraction have been and are at present used as reference. This conventional method is cheap and accurate, and this is why it has been the most used extraction technique worldwide for a number of decades. On the other hand some modern methods of fat determination are needed. Supercritical Fluid Extraction is quick, safe, and it eliminates any hazardous chemicals or solvents used in traditional extraction methods. For this purpose we used TFE 2000 fat analyzer (LECO Corporation). For the methods used the following validation parameters were determined: accuracy, precision, intermediate precision, correctness. The fat content in black pudding and luncheon meat ranged from 11.5 ? 4.5 g/100g (TFE) to 12.1 ? 0.0 g/100g (Soxhlet) and from 13.2 ? 0.5 g/100g (Soxhlet) to 13.8 ? 0.7 g/100g (TFE), respectively. For wiener samples we received values between 15.7 ? 0.4 g/100g (TFE) to 17.8 ? 0.1 g/100g (Soxhlet). The fat content in bacon samples ranged from 48.2 ? 2.5 g/100g (TFE) to 48.7 ? 0.7 g/100g (Soxhlet). The results received remain consistent with the values given in the Polish ?Food Composition Tables?. The application of the methods described above for the determination of fat content in animal - derived products is dependent ie.: on the purpose of analysis, the amount of fat in food product sample and the time for receiving the results.

scholarly journals Comparison of Five Extraction Methods for Determination of Incurred and Added Pesticides in Dietary Composites

2002 ◽  
Vol 85 (5) ◽  
pp. 1167-1176 ◽  
Author(s):  
Laura Rosenblum ◽  
Sherry T Garris ◽  
Jeffrey N Morgan
Keyword(s):  
Water Content ◽  
Environmental Protection Agency ◽  
Extraction Methods ◽  
Microwave Assisted ◽  
Assisted Extraction ◽  
The Individual ◽  
Cis And Trans ◽  
Composite Samples ◽  
Selection Of

Abstract The National Exposure Research Laboratory of the U.S. Environmental Protection Agency conducts research to measure exposure of individuals to chemical pollutants through the diet. In support of this research, methods are being evaluated for the determination of pesticides in dietary composite samples. In the present study, Soxhlet, blender, microwave-assisted, pressurized fluid, and supercritical fluid extraction methods were compared for the determination of incurred and added pesticides in 4 dietary composites, which varied in fat and water content. Incurred pesticides were chlorothalonil, chlorpyrifos, DDE, dicloran, dieldrin, endosulfan I, malathion, cis- and trans-permethrin, and trifluralin. Added pesticides were α- and γ-chlordane, hexachlorobenzene, and fonofos. Concentrations of the individual pesticides were between 0.2 and 20 ng/g composite. All 5 methods tested could extract pesticides from dietary composites. Most incurred pesticides were recovered from the dietary composites within the range of 59–140% of expected values. Recoveries of added pesticides were between 60 and 130%. Microwave-assisted extraction led to significantly higher concentrations of 7 pesticides. Blender extraction yielded significantly higher concentrations of chlorothalonil and fonofos. Water content was a significant factor in the recovery of chlorothalonil, and fat content was a significant factor in the recovery of fonofos. In designing an exposure study, the selection of the extraction method would be determined by number of samples to be extracted, analyte stability, and cost.

scholarly journals Validation of a UV Spectrometric Method for the Assay of Tolfenamic Acid in Organic Solvents

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Sofia Ahmed ◽  
Nafeesa Mustaan ◽  
Muhammad Ali Sheraz ◽  
Syeda Ayesha Ahmed un Nabi ◽  
Iqbal Ahmad
Keyword(s):  
Organic Solvents ◽  
Statistical Data ◽  
Tolfenamic Acid ◽  
The Other ◽  
Spectrometric Method ◽  
Solution Stability ◽  
Solvent Interactions ◽  
Stock Solutions ◽  
Better Than

The present study has been carried out to validate a UV spectrometric method for the assay of tolfenamic acid (TA) in organic solvents. TA is insoluble in water; therefore, a total of thirteen commonly used organic solvents have been selected in which the drug is soluble. Fresh stock solutions of TA in each solvent in a concentration of 1 × 10−4 M (2.62 mg%) were prepared for the assay. The method has been validated according to the guideline of International Conference on Harmonization and parameters like linearity, range, accuracy, precision, sensitivity, and robustness have been studied. Although the method was found to be efficient for the determination of TA in all solvents on the basis of statistical data 1-octanol, followed by ethanol and methanol, was found to be comparatively better than the other studied solvents. No change in the stock solution stability of TA has been observed in each solvent for 24 hours stored either at room (25±1°C) or at refrigerated temperature (2–8°C). A shift in the absorption maxima has been observed for TA in various solvents indicating drug-solvent interactions. The studied method is simple, rapid, economical, accurate, and precise for the assay of TA in different organic solvents.

scholarly journals Structures and Properties of Diastereomeric Multi-component Crystals

2014 ◽  
Vol 70 (a1) ◽  
pp. C1010-C1010
Author(s):  
Dominique Bock ◽  
Christian Lehmann
Keyword(s):  
Absolute Configuration ◽  
The Other ◽  
Chiral Molecules ◽  
Preferential Formation ◽  
Structure Solution ◽  
Structures And Properties ◽  
Solution Methods ◽  
Diffraction Patterns ◽  
Selection Of

Multi-component crystals composed of two different chiral molecules have the potential to form diastereomers. In the present study a selection of chiral amides and acids was employed to form multi-component crystals. Since growing these multi-component crystals from solution failed, solvent assisted grinding was used. The resulting diastereomeric pairs, which are present as polycrystalline powders showed distinctly different powder diffraction patterns. In order to elucidate the crystal structures direct space global optimization structure solution methods were successfully used in several cases. A potential application of these diastereomeric multi-component crystals is the determination of the absolute configuration of one of the two components based on the known absolute configuration of the other.[1] In addition, Raman spectroscopy and DSC were employed to determine thermodynamic properties. In subsequent grinding experiments racemic conglomerates and racemates formed the starting material. These experiments demonstrated in several cases a relationship between melting point differences and preferential formation of only one diastereomer.

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

Determination of the lattice translation across {110} APBs in GaAs

1988 ◽  
Vol 46 ◽  
pp. 600-601
Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter
Keyword(s):  
Grain Boundaries ◽  
Lower Energy ◽  
Antiphase Boundary ◽  
The Other ◽  
Boundary Structure ◽  
Interface Plane ◽  
Inversion Symmetry ◽  
High Angle ◽  
Equilibrium Distance

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.

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