scholarly journals Analysis of Calcareous Soils for Two Various Facies within the Nature Reserve of El-Mergueb (M’sila, Algeria)

2021 ◽  
Vol 40 (4) ◽  
pp. 337-347
Author(s):  
Samir Mezani ◽  
Amina Adjabi ◽  
Hachemi Sidi ◽  
Rabah Bounar ◽  
Hamid Reza Naseri

Abstract This research was conducted on the protected area of El-Mergueb at M’sila province. The zone of El-Mergueb is located about 180 km south of the capital Algiers, at an altitude from 550 to 800 m, and is characterised by arid climate. The zone of El-Mergueb has a landscape from the steppe to Alfa that lies just as well in the flat ridges hills that in their slopes and in the top part of the ravines. Alfa tenacissima dominates the most geographical space of El-Mergueb. This study is based on the analysis of the homogenous and heterogeneous facies by the determination of the content of calcium carbonate (CaCO3), active calcium carbonate (ACCE) and gypsum through monitoring these chemical parameters during 3 years: 2017, 2018, 2019. Six soil profiles of 15 soil samples collected in the site of study were studied and several chemical soil properties were considered. These factors included: soil pH, calcium carbonate (CaCO3), active total carbonate (CA), gypsum (CaSO4) and electrical conductivity (EC). Principal component analysis (PCA) was used to identify the variations in soil properties. Results showed that there are significant relationships between some soil factors and two PCA axes. The results thus obtained showed that the content of CaCO3 and CA analysed ranged from average to high. The average of gypsum and salinity was low. Floristic diversity defined 284 species. The data on the chemical characteristics of the soil studied have been the subject of a detailed statistical analysis (PCA). Our database consisted of quantitative variables. The implementation of the PCA to the soils studied showed a major dominance of the limestone in the two stations, which explains the alkaline pH and the low concentration of gypsum. Finally, these types of high total limestone are the most observed in the majority of steppe and arid soils.

Soil Research ◽  
2005 ◽  
Vol 43 (4) ◽  
pp. 541 ◽  
Author(s):  
A. Al-Busaidi ◽  
P. Cookson ◽  
T. Yamamoto

Determination of pH assists in understanding many reactions that occur in soil. However, measured values of soil pH can be affected by the procedure used for determination and by a range of soil properties. In this study, pH was measured in different electrolytes [distilled water (pHw), 0.01 m CaCl2 (pHca), 1 m KCl (pHk), and 0.01 m BaCl2 (pHba)] with different soil : solution ratios (i.e. 1 : 1, 1 : 2.5, 1 : 5), the main objective being to study the influence of different electrolytes on the suspension effect of pH in calcareous soils. Soil pH measured in water showed significant differences between different dilution ratios and was highly influenced by the ‘suspension effect’. Other electrolytes (CaCl2, KCl, BaCl2) were little affected by the suspension effect, giving approximately stable values when pH was measured with and without stirring. High soil salinity appeared to suppress any suspension effect in a manner similar to electrolytes when added to non-saline soils.


2020 ◽  
pp. 23-33
Author(s):  
Elena A. Zaeva-Burdonskaya ◽  
Yuri V. Nazarov

This article addresses one of the most actively developing types of design activities – light design. The article comprises quotes of the leading Russian and foreign light design specialists published over the previous five years, as well as the authors’ own conclusions. The thoughts quoted in the article are sometimes opposite to each other and reflect the wide spectrum of professional practice. They reflect the initial opinions of analysts and experts which are often diverging. All of the specialists point at the interdisciplinary nature of the new profession, which imposes additional load on a designer overloaded enough already by the scope and speed of the problems being solved nowadays. The discussion of the new profession of light designer initiated on the pages of professional publications is especially important in view of the development of professional standards and standards of design and architectural education, as well as creation of new educational programmes based on various approaches to the subject in technical and humanitarian institutions. The goal of this article is to introduce light design into the field of fully legitimate sections of design culture, to define the authentic scientific basis of the new creative profession, to initiate a foundation for self-determination of the new synthetic area, which materially affects the state of the profession as a whole and the life standards of a wide variety of consumers. In order to reach the set goal, a comparative and analytical method of study was selected, which allows studying the problem to a large extent and from all angles and finding the ways of overcoming the challenges emerging in the area of the new activity.


Author(s):  
Evgeniya Mikhailovna Popova ◽  
Guzel Mukhtarovna Guseinova ◽  
Sergei Borisovich Milov

The deficit of subnational budgets and deceleration capital investments in multiple Russian regions increase the relevance of research aimed at improvement of tax incentivizing practice of the regional investment process. The studies focused on determination of the impact of socioeconomic and institutional factors upon the efficiency of investment tax expenses obtained wide circulation within the foreign scientific literature. The subject of this article is the assessment of sensitivity of the efficiency of regional tax expanses towards investment attractiveness of the types of economic activity carried out by the residents of territories of advanced socioeconomic development, created in the subjects of Far Easter Federal District. The scientific novelty and practical values of this research consists in substantiation of the reasonableness of assessment of investment attractiveness of the types of economic activity that are stimulated by tax incentives. Methodology for assessing investment attractiveness is proposed and tested. The conclusion is made that in case of low investment attractiveness of the type of economic activity, which was planned to support by tax incentives, it is required to conduct and additional analysis to avoid unjustified tax expanses.


2019 ◽  
pp. 129-136 ◽  
Author(s):  
E. A. Khorova ◽  
A. V. Myshlyavtsev

The subject of the study were rubber mixtures based on hydrogenated butadiene-nitrile rubbers (HNBR) Therban, Zetpol, NBR-B with an acrylonitrile (AN) content of 34% to 49% and unsaturation of 0.9% to 22% with sulfuric, peroxide and sulfuric-peroxide cure systems. The purpose of the study was to determine the effect of the AN content and the degree of unsaturation of HNBR on the properties of rubbers in products designed for operation under the influence of fuels and oils at increased temperatures.The results of the determination of the mass swelling of rubbers in hydrocarbon media and the relative elongation in the process of thermal aging in air and in oil at increased temperatures are presented. The conclusion was made on the use of HNBR mixture with maximum content of AN (49%), with low (6%) and extremely low (0.9%) ODS content and sulfuric peroxide cure system to extend the product service temperature limit to 150°C.


Author(s):  
Chakravarthi Ram-Prasad

The Introduction outlines the various chapters. It then situates the question of ‘body’ in the modern Western philosophical tradition following Descartes, and argues that this leaves subsequent responses to come under one of three options: metaphysical dualism of body and subject; any anti-dualist reductionism; or the overcoming of the divide. Describing the Phenomenology of Merleau-Ponty as a potent example of the third strategy, the Introduction then suggests his philosophy will function as foil to the ecological phenomenology developed and presented in the book. Moreover, one approach within the Western Phenomenological tradition, of treating phenomenology as a methodology for the clarification of experience (rather than the means to the determination of an ontology of the subject) is compared to the approach in this book. Since classical India, while understanding dualism, did not confront the challenge of Descartes (for better or for worse), its treatment of body follows a different trajectory.


2007 ◽  
Vol 90 (2) ◽  
pp. 391-404 ◽  
Author(s):  
Fadia H Metwally ◽  
Yasser S El-Saharty ◽  
Mohamed Refaat ◽  
Sonia Z El-Khateeb

Abstract New selective, precise, and accurate methods are described for the determination of a ternary mixture containing drotaverine hydrochloride (I), caffeine (II), and paracetamol (III). The first method uses the first (D1) and third (D3) derivative spectrophotometry at 331 and 315 nm for the determination of (I) and (III), respectively, without interference from (II). The second method depends on the simultaneous use of the first derivative of the ratio spectra (DD1) with measurement at 312.4 nm for determination of (I) using the spectrum of 40 μg/mL (III) as a divisor or measurement at 286.4 and 304 nm after using the spectrum of 4 μg/mL (I) as a divisor for the determination of (II) and (III), respectively. In the third method, the predictive abilities of the classical least-squares, principal component regression, and partial least-squares were examined for the simultaneous determination of the ternary mixture. The last method depends on thin-layer chromatography-densitometry after separation of the mixture on silica gel plates using ethyl acetatechloroformmethanol (16 + 3 + 1, v/v/v) as the mobile phase. The spots were scanned at 281, 272, and 248 nm for the determination of (I), (II), and (III), respectively. Regression analysis showed good correlation in the selected ranges with excellent percentage recoveries. The chemical variables affecting the analytical performance of the methodology were studied and optimized. The methods showed no significant interferences from excipients. Intraday and interday assay precision and accuracy values were within regulatory limits. The suggested procedures were checked using laboratory-prepared mixtures and were successfully applied for the analysis of their pharmaceutical preparations. The validity of the proposed methods was further assessed by applying a standard addition technique. The results obtained by applying the proposed methods were statistically analyzed and compared with those obtained by the manufacturer's method.


2021 ◽  
pp. 000370282110329
Author(s):  
Ling Wang ◽  
Mario O. Vendrell-Dones ◽  
Chiara Deriu ◽  
Sevde Doğruer ◽  
Peter de B. Harrington ◽  
...  

Recently there has been upsurge in reports that illicit seizures of cocaine and heroin have been adulterated with fentanyl. Surface-enhanced Raman spectroscopy (SERS) provides a useful alternative to current screening procedures that permits detection of trace levels of fentanyl in mixtures. Samples are solubilized and allowed to interact with aggregated colloidal nanostars to produce a rapid and sensitive assay. In this study, we present the quantitative determination of fentanyl in heroin and cocaine using SERS, using a point-and-shoot handheld Raman system. Our protocol is optimized to detect pure fentanyl down to 0.20 ± 0.06 ng/mL and can also distinguish pure cocaine and heroin at ng/mL levels. Multiplex analysis of mixtures is enabled by combining SERS detection with principal component analysis and super partial least squares regression discriminate analysis (SPLS-DA), which allow for the determination of fentanyl as low as 0.05% in simulated seized heroin and 0.10% in simulated seized cocaine samples.


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