scholarly journals Chemical Composition of Scots Pine Bark as a Bioindicator of Environmental Quality in Riga, Latvia / Priežu Mizu ķīmiskais Sastāvs Kā Vides Stāvokļa Bioindikators Rīgā (Latvija)

2015 ◽  
Vol 69 (3) ◽  
pp. 87-97
Author(s):  
Gunta Čekstere ◽  
Māris Laiviņš ◽  
Anita Osvalde
Keyword(s):  
Chemical Composition ◽  
Environmental Quality ◽  
Rural Areas ◽  
Chemical Elements ◽  
Urban Forests ◽  
Background Level ◽  
Pine Bark ◽  
Element Concentrations ◽  
Building Area

Abstract The chemical composition of pine bark was used for the determination of environmental quality in Rīga. Bark samples were collected at 54 sites in Rīga differing in vegetation and building area characteristics (urban forests, parks and cemeteries, dwelling houses, and streets and railway zones) and at 52 sites from rural areas in Latvia (background level). Concentrations of Ca, Mg, Na, K, Fe, Mn, Zn, Ni, Cu, Cd, Pb, and pH was determined in the samples. The results showed significantly higher concentrations of chemical elements in pine bark collected in Rīga, compared to background levels: Fe and Cu concentrations three times higher, and other elements - up to 1.8 times. The highest element concentrations in Rīga were near streets (Sarkandaugava, Jaunmīlgrāvis, Daugavgrīva, Čiekurkalns, Imanta area, etc.). Element concentration and pH was significantly dependent on the distance from the closest street. The lowest element concentrations were found in urban forests (Jugla, Biķernieki, Beberbeķi) and parks and cemeteries (I Forest Cemetery, Jaunciema Cemetery). Mežaparks (forest), Sarkandaugava, Jaunmīlgrāvis, and Vecmīlgrāvis together formed the most polluted area in Rīga due to the close location near and downwind from the harbour.

About the possibility of identification of articles from steels, aluminum, copper and alloys on their basis on the expanded micro-impurity elemental composition

2021 ◽  
pp. 51-56
Author(s):  
Yu. B. Sazonov ◽  
D. Yu. Ozherelkov ◽  
R. Sh. Latypov ◽  
E. E. Gorshkov
Keyword(s):  
Spectral Analysis ◽  
Chemical Composition ◽  
Elemental Composition ◽  
Chemical Elements ◽  
Copper Alloys ◽  
Minimal Amount ◽  
Elementary Composition ◽  
Geometric Size ◽  
The Common

Possibility of determination of the fragments and articles made of different grades of steel aluminium and copper alloys and their affiliation to the common melt was examined via the methods of photoelectric spectral analysis based on composition of micro-impurities. Chemical elements with micro-impurities were revealed; they allow to determine affiliation of metal fragments to one melt. Ultimately possible deviations of micro-impurities within one melt were obtained. The technique allowing to establish affiliation of fragments to the common melt based on their elementary composition of micro-impurities with minimal amount of measurements was suggested based on the obtained results. The minimal geometric size of a sample available for analysis was determined; it allows to classify the examined fragments to one melt based on the results of investigation of expanded elementary composition of micro-impurities. Practical opportunities of this technique were displayed on the example of the alloys with different chemical composition.

Lateral resolution of the electron microbeam analysis

1978 ◽  
Vol 36 (1) ◽  
pp. 542-543
Author(s):  
H.J. Dudek
Keyword(s):  
Quantitative Analysis ◽  
Depth Resolution ◽  
Lateral Resolution ◽  
Cylindrical Particle ◽  
Correction Procedure ◽  
X Ray ◽  
Element Concentrations ◽  
Microbeam Analysis ◽  
The Matrix

The chemical inhomogenities in modern materials such as fibers, phases and inclusions, often have diameters in the region of one micrometer. Using electron microbeam analysis for the determination of the element concentrations one has to know the smallest possible diameter of such regions for a given accuracy of the quantitative analysis.In th is paper the correction procedure for the quantitative electron microbeam analysis is extended to a spacial problem to determine the smallest possible measurements of a cylindrical particle P of high D (depth resolution) and diameter L (lateral resolution) embeded in a matrix M and which has to be analysed quantitative with the accuracy q. The mathematical accounts lead to the following form of the characteristic x-ray intens ity of the element i of a particle P embeded in the matrix M in relation to the intensity of a standard S

Preparation of graft copolymers by the reaction of polymeric acyl chlorides with monohydroxy-terminated polymers: An introductory study

1988 ◽  
Vol 53 (8) ◽  
pp. 1735-1744 ◽  
Author(s):  
Jitka Horská ◽  
Jaroslav Stejskal ◽  
Pavel Kratochvíl ◽  
Aubrey D. Jenkins ◽  
Eugenia Tsartolia ◽  
...  
Keyword(s):  
Light Scattering ◽  
Chemical Composition ◽  
Statistical Model ◽  
Graft Copolymers ◽  
Coupling Reaction ◽  
Molecular Characteristics ◽  
Gel Formation ◽  
Acyl Chlorides ◽  
Molecular Weights

An attempt was made to prepare well-defined graft copolymers by the coupling reaction between acyl chloride groups located along the backbone chain and monohydroxy-terminated grafts prepared separately. The molecular weights and the parameters of heterogeneity in chemical composition of the products were determined by light scattering and osmometry. The determination of molecular characteristics revealed that the degree of grafting was low. The results therefore could not be confronted with a statistical model at this stage. The problems encountered in the synthesis, e.g., gel formation, and the data relating to the soluble products are discussed.

scholarly journals Chemical Composition of the RS CNn-Type Star 33 Piscium

2011 ◽  
Vol 20 (1) ◽  
Author(s):  
G. Barisevišius ◽  
G. Tautvaišienė ◽  
S. Berdyugina ◽  
Y. Chorniy ◽  
I. Ilyin
Keyword(s):  
Chemical Composition ◽  
Chemical Elements ◽  
Type Star

AbstractAbundances of 22 chemical elements, including the key elements and isotopes such as

scholarly journals Hematological Features in Sheep with IgG and IgM Antibodies against Borrelia burgdorferi sensu lato

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 164
Author(s):  
Labrini V. Athanasiou ◽  
Victoria M. Spanou ◽  
Eleni G. Katsogiannou ◽  
Panagiotis D. Katsoulos
Keyword(s):  
Borrelia Burgdorferi ◽  
Rural Areas ◽  
Blood Analysis ◽  
Borrelia Burgdorferi Sensu Lato ◽  
Igm Antibodies ◽  
Group A ◽  
Group B ◽  
Group D ◽  
Immunofluorescence Antibody

Exposure of sheep to Borreliaburgdorferi sensulato (s.I.) complex, the causative agent of Lyme borreliosis (LB), has been reported in tick-abundant areas worldwide, while no data have been reported in Greece. The aim of the study was to identify the hematological alterations in sheep with seropositivity against Borrelia burgdorferi (s.I.). Blood samples were obtained from 318 tick infested sheep for blood analysis and serological determination of IgG and IgM antibodies against B. burgdorferi by indirect immunofluorescence antibody (IFA) assay after exclusion of endo-ectoparasites and other tick-borne infections. A total number of 162 sheep met the inclusion criteria, allocated in four groups based on the presence or absence of IgG and/or IgM; sheep found negative for IgM and IgG (Group A), positive for IgM (Group B), positive for both IgM and IgG (Group C) and positive for IgG (Group D). Anemia, thrombocytopenia and normal or decreased leukocyte count, mainly due to lymphopenia were the main hematological features observed in seropositive sheep. The presence of these features raises the suspicion of Borrelia infection in tick infested sheep. The seropositivity of 23.58% in sheep raises concerns of Borrelia circulation, especially in rural areas and potential risk of transmission to humans.

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