Climate and relief influence on particle size distribution and chemical properties of Pseudogley soils in Croatia

CATENA ◽  
2015 ◽  
Vol 127 ◽  
pp. 340-348 ◽  
Author(s):  
Vedran Rubinić ◽  
Boris Lazarević ◽  
Stjepan Husnjak ◽  
Goran Durn
2020 ◽  
Vol 26 (1) ◽  
pp. 82-93
Author(s):  
Reihaneh Radmanesh ◽  
◽  
Mohsen Nabi Meybodi ◽  
Vahid Ramezani ◽  
Maryam Akrami ◽  
...  

Aims: Any pharmaceutical product made in pharmacy, hospital or factory may be contaminated with microbes. This contamination can originate from raw materials or during production. Hence, it is important to study the physical and chemical properties and stability of compounded drugs. Methods & Materials: In this study, first a specific sample of prescribed medication was ordered from 63 pharmacies in Yazd, Iran. After collecting the samples, the amount of microbial contamination, viscosity and particle size distribution and their stability were investigated and their results were compared to the standard levels. Findings: Based on the results, 31.7% of the samples had discoloration and 23.8% showed creaming phenomenon. In terms of particle size distribution, 57.1% of the samples had a 20-40 μm particle size and 49.2% had a viscosity equal to 2500-3000 centipoise. Regarding stability, 12.6% of the samples underwnet phase change at 30-40°C. About of the amount of hydroquinone in samples, 35% had acceptable amount. In 23.8% of the samples, fungal infection was observed. Conclusion: Contrary to a popular belief that the compounded medicines produced in pharmacies have microbial contamination, the results of this study showed that the microbial contamination of these compounded medications is low.


1971 ◽  
Vol 50 (6) ◽  
pp. 1616-1620 ◽  
Author(s):  
Brian E. Kent ◽  
Alan D. Wilson

The effects of particle size of the powder on the physical and chemical properties of dental silicate cements were studied. Suggestions are given for improvement of these cements by changes in the particle size distribution of the powder.


Foods ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1832
Author(s):  
Elías Arilla ◽  
Marta Igual ◽  
Javier Martínez-Monzó ◽  
Pilar Codoñer-Franch ◽  
Purificación García-Segovia

Resistant maltodextrin (RMD) is a water-soluble fibre that can be fermented in the colon and exert prebiotic effects. Therefore, its addition to food and beverage products could be beneficial from both technological and nutritional viewpoints. However, to date, most studies have focused on the stability of the prebiotic fibre rather than its impact in the original food matrices. Therefore, this work aimed to evaluate the addition of RMD on the physico-chemical properties of pasteurised orange juice (with and without pulp). °Brix, pH, acidity, particle size distribution, density, turbidity, rheology, and colour were measured in orange juices with increasing RMD concentrations (2.5, 5, and 7.5%). Control samples without RMD were also prepared. RMD added soluble solids to the orange juice, affecting the °Brix, density, turbidity, and rheology. Slight colour differences were observed, and lower citric acid content was achieved because of orange juice replacement with RMD. Differences in particle size distribution were exclusively because of pulp content. Further studies are needed to elucidate if potential consumers will appreciate such physico-chemical changes in organoleptic terms.


2014 ◽  
Vol 75 (3) ◽  
pp. 253-262
Author(s):  
Jarosław Lasota ◽  
Ewa Błońska ◽  
Maciej Zwydak ◽  
Tomasz Wanic

Abstract The physical and chemical properties of soil are the basic features that are used in the assessment of mountain sites. The aim of this study was to produce a simple key for classifying forest sites in mountain areas using soil particle size distribution. 200 plots (standard typological space) were selected for examination, most of which are typical of the Carpathians - being dominated by flysch rock. A few plots were located in the Sudety and Tatra Mountains, which have a different surface geology, mostly metamorphic rock and granite. The study proved that soil properties (reaction, base saturation, content of base cations, organic carbon and nitrogen) are helpful in distinguishing and assigning soils to particular site types. The particle size distribution of forest mountain sites separated into different categories in terms of productivity. These results can be used to improve the classification of forest mountain sites.


Author(s):  
O. Tonkha ◽  
O. Bukova ◽  
O. Pikovska ◽  
I. Fedosiy ◽  
O. Menshov ◽  
...  

Silicon plays the significant role in the growth and development of plants, their resistance to stress conditions. However, there is limited research on the content of various forms of silicon in soils, the relationship with soil cations, which is particularly relevant in the context of intensive agriculture and climate aridization in Ukraine. The purpose of the present study was to determine the content of silicon compounds of different mobility in the arable soils of the Khmelnytsky region, the spatial variation of these parameters, and to detect the dependence between the content of silicon compounds and soil particle size. The study was performed at the area of LLC "Lotivka Elit" of Shepetivka district of Khmelnitsky region in field crop rotation. We determined for soil samples: particle size distribution and content of fractions of granulometric elements of different sizes, pH of salt extraction (1,0 M KCl solution), humus content, calcium and magnesium exchangeable compounds by extraction with 1,0 M KCl solution. The results showed that the content of silicon compounds in soils depends on the particle size distribution of soil, the value of exchangeable acidity, humus content, and the composition of exchangeable cations.


1986 ◽  
Vol 34 (1) ◽  
pp. 91-102
Author(s):  
A.G. Jongmans ◽  
R. Miedema

The Meuse terraces of Late Weichselian and Holocene age can be subdivided into 4 levels. The youngest Late Weichselian terrace occurs partly along and close to the present-day Meuse. On recent soil maps the well drained brown soils, occupying the highest positions of this terrace level, have been indicated as Plaggepts. This implies the presence of a plaggen epipedon of more than 50 cm thick. Three characteristic soil profiles were studied macromorphologically and micromorphologically and samples were analysed for particle size distribution and selected chemical properties. It is concluded that the brown top-soils are due to periodic Holocene sedimentation followed by homogenization. The sandy loam and finer-textured Late Weichselian subsoils have a clear argillic horizon. These soils should be classified as Alfisols (Luvisols) rather than Plaggepts. (Abstract retrieved from CAB Abstracts by CABI’s permission)


Author(s):  
Farhan KHAN ◽  
Bhumika DAS ◽  
Nomesh DEWANGAN

This study was conducted to have a detailed analysis of the geotechnical properties of expansive soil and fly ash from Sipat thermal power plant. It reported the findings of laboratory studies on certain common physical and geotechnical properties. The chemical properties and morphology of the black cotton soil (BCS) and fly ash is also determined using scanning electron microscopy and X-ray diffraction test. The geotechnical test includes determining specific gravity, particle size distribution, moisture content, standard proctor test, free swell index, and Atterberg’s limit. The different compositions of expansive soil with fly ash, yellow soil, moorum, and sand are studied. BCS was evaluated with fly ash, fly ash and sand, BCS with yellow soil, and moorum and fly ash. The study also analyzed the details and results of different tests conducted on soil samples. The results showed that strength and fly ash are inversely proportional; as fly ash increases, strength decreases, and vice versa. Fly ash was added from 20 to 80 % by replacing expansive soil by weight. The results indicated that expansive soil can be stabilized by the addition of fly ash to a limit of 10 to 20 %. HIGHLIGHTS The XRD And SEM results shows the mineral present in the FlyAsh and Expansive soil The geotechnical properties of Flyash and expansive soil is determined The OMC increases with decrease in densities The Particle size distribution curve shows the soil is GW soil GRAPHICAL ABSTRACT


Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1538
Author(s):  
Konrad Gruber ◽  
Irina Smolina ◽  
Marcin Kasprowicz ◽  
Tomasz Kurzynowski

In this paper, a detailed assessment of Inconel 718 powder, with varying degrees of degradation due to repeated use in the Laser Powder Bed Fusion (LPBF) process, has been undertaken. Four states of IN718 powder (virgin, used, overflow and spatter) were characterized in terms of their morphology, flowability and physico-chemical properties. Studies showed that used and overflow powders were almost identical. The fine particle-size distribution of the virgin powder, in which 50% of particles were found to be below the nominal particle-size distribution (PSD), was recognized as the main reason for its lower flowability and the main cause of the differentiation between virgin, used and overflow powders. Only spatter powder was found to be degraded enough to preclude its direct LPBF reuse. The oxygen content in the spatter powder exceeded the limit value for IN718 by 290 ppm, and aluminum oxide spots were found on the spatter particles surfaces. Laser absorption analysis showed 10 pp higher laser absorption compared to the other powders. The results of evaluation showed that IN718 powder is resistant to multiple uses in the LPBF process. Due to the low degradation rate of IN718 powder, overflow powder can be re-enabled for multiple uses with a proper recycling strategy.


Author(s):  
Dmitriy V. Yunovidov ◽  
Maksim N. Nadezhin ◽  
Konstantin V. Aksenchik ◽  
Elizaveta E. Sidorova ◽  
Irina V. Nadezhina

The article discusses the relationship between the mass of the laboratory sample and the homogeneity of its particle size distribution. The aim of the work is to estimate the limits of the sample mass reduction, at which it remains representative in particle size distribution. A relation was pointed out between the chemical and physical properties and the particle size distribution of fertilizers. The use of this parameter as one of the basic physical properties of industrially produced mineral fertilizers was justified. At the same time, using a smaller sample will reduce the time for analysis in industrial laboratories. An experiment was proposed and implemented to assess the representativeness of sample of fertilizers with different masses. Samples of several brands of industrially produced granulated mineral fertilizers were studied. A sieve analysis of samples was carried out in accordance with accepted standards (for < 1 mm, 1-2 mm, 2-3.15 mm, 3.15-4 mm, 4-5 mm, 5-6.3 mm, > 6.3 mm fractions). A comparison between the obtained results and industry-specific technique for determining the particle size distribution on the woven sieve was given. According to the obtained data, the main statistical characteristics of the analysis were calculated: mathematical expectation (average value), standard deviation and confidence interval. The homogeneity of the average values and variances of the obtained samples for the 50 and 150 g of fertilizers was investigated using Student's and Fisher's tests for a 0.05% level of significance. To confirm the test results, a graphic distribution of sample with different mass and the fraction < 2 mm was built. Conclusion about the allowable mass of a representative sample of granular mineral fertilizers for analyzing the particle size distribution and the associated with physical and chemical properties of fertilizers was made.


Sign in / Sign up

Export Citation Format

Share Document