Spektralna istraživanja spinelnog feritnog sistema NixZn1−xFe2O4

X-ray diffraction, DTA, IR and SEM investigations were carried out for a series of samples of the system NixZn1-xFe2O4 (with x=0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) prepared using the usual ceramic technique. The analysis of X-ray diffraction indicates that the samples have single phase with spinel cubic structure. The lattice constant (a), radius of tetrahedral ions (rtet), bulk density (D) and theoretical density (Dx) were found to decrease while the porosity (P) increases as the content of nickel ions (x) increases. SEM images indicate observable variations between the different compositions. IR absorption spectra showed the four characteristic peaks of ferrites. The position and intensity of the peaks are markedly composition dependent.Na nizu uzoraka sistema NixZn1−xFe2O4 (za x = 0,0, 0,2 , 0,4 , 0,6 , 0,8 i 1,0) pripremljenih uobičajenom keramičkom tehnikom, izvršena su mjerenja difrakcijom rendgenskog zračenja, diferencijalna termička analiza, optička mjerenja u infracrvenom području i snimanja skanirajućim elektronskim mikroskopom. Analiza difrakcije rendgenskog zračenja indicira da uzorci imaju jednu fazu sa spinelnom kubičnom strukturom. Nadeno je da konstanta rešetke, promjeri tetrahedralnih iona, volumna i teoretska gustoća padaju a poroznost raste s porastom sadržaja nikla. Slike dobivene skanirajućim elektronskim mikroskopom indiciraju primjetne promjene među različitim smjesama. Spektri infracrvene apsorpcije pokazuju četiri karakteristična vrha za ferite. Položaj i intenzitet vrhova značajno ovise o sastavu sistema

Spektralna istraživanja spinelnog feritnog sistema NixZn1−xFe2O4

X-ray diffraction, DTA, IR and SEM investigations were carried out for a series of samples of the system NixZn1-xFe2O4 (with x=0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) prepared using the usual ceramic technique. The analysis of X-ray diffraction indicates that the samples have single phase with spinel cubic structure. The lattice constant (a), radius of tetrahedral ions (rtet), bulk density (D) and theoretical density (Dx) were found to decrease while the porosity (P) increases as the content of nickel ions (x) increases. SEM images indicate observable variations between the different compositions. IR absorption spectra showed the four characteristic peaks of ferrites. The position and intensity of the peaks are markedly composition dependent.Na nizu uzoraka sistema NixZn1−xFe2O4 (za x = 0,0, 0,2 , 0,4 , 0,6 , 0,8 i 1,0) pripremljenih uobičajenom keramičkom tehnikom, izvršena su mjerenja difrakcijom rendgenskog zračenja, diferencijalna termička analiza, optička mjerenja u infracrvenom području i snimanja skanirajućim elektronskim mikroskopom. Analiza difrakcije rendgenskog zračenja indicira da uzorci imaju jednu fazu sa spinelnom kubičnom strukturom. Nadeno je da konstanta rešetke, promjeri tetrahedralnih iona, volumna i teoretska gustoća padaju a poroznost raste s porastom sadržaja nikla. Slike dobivene skanirajućim elektronskim mikroskopom indiciraju primjetne promjene među različitim smjesama. Spektri infracrvene apsorpcije pokazuju četiri karakteristična vrha za ferite. Položaj i intenzitet vrhova značajno ovise o sastavu sistema

Električna i termoelektrična svojstva čistog i supstituiranih bakrenih ferita

Samples of the CuFe2-xAlxO4 system with x=0, 0.2, 0.4 and 0.6 were prepared. The single phase spinel structure was verified by X-ray diffraction method. The thermoelectric power (a) and dc electrical resistivity (r) were studied as a function of temperature and composition. The results show that the resistivity increases and the transition temperature decreases with increasing the aluminium substitution. The activation energy in ferrimagnetic region is lower than that in paramagnetic region. The drift mobility of carriers increases exponentially with temperature as expected for ferrites.Priređeni su uzorci sistema CuFe2−xAlxO4 sa x = 0, 0,2, 0,4 i 0,6. Proučavana je termoelektrična sila i dc električna otpornost u ovisnosti o temperaturi i sastavu. Rezultati mjerenja pokazuju da se otpornost povećava a temperatura prijelaza smanjuje sa povećanjem koncentracije aluminija. Aktivacijska energija veća je u feromagnetskoj nego u paramagnetskoj fazi. U skladu s očekivanjem, ustanovljeno je da se mobilnost nosilaca naboja u feritima eksponencijalno povećava s temperaturom

Reactivity of Some Transition Metal Complexes of Anthranilic Acid with Leucine and Monochloroacetic Acid

Six mixed ligand complexes of [M(Anth) (Leu)] . nH20 and [M(Anth) (Clac)] types, where M=Co, Ni and Cu; n e=O, 2 or 4; Anth e anthranilate and Leu e leucinate, have been prepared. They were characterized on the basis of their analyses, infrared and UV-VIS spectra, magnetic and thermal measurements. All the compounds were found to have presumably distorted octahedral configurations. The polymeric structure of the complexes is indicated by their insolubility and high thermal stability

Magnetic and Spectral Properties of 2-Methylbenzoxazole, Benzothiazole, and 2-Methylbenzothiazole Complexes with Copper(II) Dichloroacetate

The complexes in the title have been synthesized and their magnetic and spectral behaviour have been studied. Magnetic susceptibility was determined in the temperature range of 80- 300 K. The IR spectra were obtained in KBr pellets, and UV spectra in acetone. The conductivity of the complexes in acetone solutions were also measured

Tribological behaviour of microalloyed and conventional C–Mn rail steels in a pure sliding condition

This paper compares the tribological behaviour of microalloyed rail steel with conventional C–Mn rail steel under different test conditions (load, temperature and humidity). Pin-on-disc tribological tests were performed inside a climate chamber under different loads (20, 30 and 40 N), relative humidity (15, 55 and 70%) and temperatures (20 and 40 ℃). After the friction and wear tests, the worn surfaces were analysed using both confocal and scanning electron microscopies. The results obtained show that the use of microalloyed steel in railway applications under severe conditions (high loads and humidity) could lead to increased service life of the rails and could extend the time between maintenance operations

Comparative histochemical study of four enzyme activities on some organs of male Schistosoma mansoni and S. haematobium

Abstract Background Enzymes are the biological catalysts which accelerate the various cellular reactions. In general, the enzymes alkaline phosphatase (ALPase), acid phosphatase (ACPase), 5′-nucleotidase (5′-Nu) and glucose-6-phosphatase (G-6-Pase) have important roles in metabolism. In the present study, a comparative account of the localization of activity of four enzymes acid phosphatase, alkaline phosphatase, glucose-6-phosphatase and 5′-nucleotidase was carried out in the organs and tissues of important human digeneans Schistosoma mansoni and Schistosoma haematobium from infected hamster (Cricentus auratus) in Egypt. Material and methods Histochemical methods were used on whole parasites to study the distribution of these enzymes. The following organs and tissues were studied: oral sucker, oesophagus, oesphageal gland, ventral sucker, ventral sucker rim, gynaecophoral canal edge, intestine, tubercles, muscles, tegumental folds, testes and excretory pore. Results Variable observations in the different organs and tissues were recorded. In S. mansoni, glucose-6-phosphatase was detected with the highest activity while alkaline phosphatase showed the lowest activity in most organs and tissues. In S. haematobium, acid phosphatase showed the highest activity and alkaline phosphatase showed the lowest activity in most organs and tissues. Although all enzymes showed clear activity in the oral sucker for both species, only glucose-6-phosphatase gave a positive reaction in the ventral sucker rim and acid phosphatase in the excretory pore of S. haematobium. On the other hand, all enzymes showed no activity in the muscles and excretory pore in S. mansoni. Conclusion ACPase activity was observed in most organs of S. haematobium. Also, G-6-Pase was detected in the ventral sucker rim and 5′-Nu was detected in tubercles. Meanwhile, ACPase and 5′-Nu were observed in the muscle fibers, testes, excretory pore and tegumental folds. On other hand, G-6-Pase is the most active enzyme in most organs of S. mansoni except the muscle fibers

Valorization potential of Egyptian mango kernel waste product as analyzed via GC/MS metabolites profiling from different cultivars and geographical origins

Abstract Increasing attention has been given to mango (Mangifera indica) fruits owing to their characteristic taste, and rich nutritional value. Mango kernels are typically discarded as a major waste product in mango industry, though of potential economic value. The present study aims to outline the first comparison of different mango kernel cvs. originated from different localities alongside Egypt, e.g., Sharqia, Suez, Ismailia, and Giza. Gas chromatography–mass spectroscopy (GC–MS) post silylation analysis revealed that sugars were the major class being detected at 3.5–290.9 µg/mg, with some kernels originating from Sharqia province being the richest amongst other cvs. In consistency with sugar results, sugar alcohols predominated in Sharqia cvs. at 1.3–38.1 µg/mg represented by ribitol, iditol, pinitol, and myo-inositol. No major variation was observed in the fatty acids profile either based on cv. type or localities, with butyl caprylate as a major component in most cvs. identified for the first time in mango. Regarding phenolics, Sedeeq cv. represented the highest level at 18.3 µg/mg and showing distinct variation among cvs. posing phenolics as better classification markers than sugars. Multivariate data analyses (MVA) confirmed that the premium cvs “Aweis and Fons” were less enriched in sugars, i.e., fructose, talose, and glucose compared to the other cvs. Moreover, MVA of Zabdeya cv. collected from three localities revealed clear segregation to be chemically distinct. Sharqia originated mango kernels were rich in sugars (e.g., glucose and fructose), whilst sarcosine esters predominated in other origins