Classification Of Elements Research Articles

ЗАКОНОМІРНОСТІ РОЗПОДІЛУ ВАЖКИХ МЕТАЛІВ НА ТЕРИТОРІЇ ВІЙСЬКОВОГО ПОЛІГОНУ "ОЛЕШКІВСЬКІ ПІСКИ"

The results of ecological-geochemical researches of soil cover of "Oleshkivski pisky" military training site, using maximum allowable concentration and classification of chemical elements with respect to hazard classes are presented. Analytical works to identify gross content and heavy metals movable forms in soils were defined by methods of atomic absorption and mass-spectometry with inductively coupled plasma (ICPMS) as well as by using gamma-ray activation analysis and X-ray fluorescence analysis. Analysis and interpretation of the coefficients of heavy metal components concentration were conducted based on landscape and geochemical fundamentals. The regular network of the protoselection points was developed. This network is built taking into account landscape structure of the territory, and provides control over landscape and geochemical currents and barriers. The average index of soil cover pollution of the polygon was calculated taking into account different toxicity of the elements. This index reaches its maximum in the region of firing positions and military polygon. The average Zc index of the upper soil level is 32, which corresponds to the dangerous level of soil pollution. The research revealed the content of moveable forms of heavy metals in soil cover of the polygon in order to identify toxic and tolerant levels of heavy metals concentration and reserve sources of elements in soils, which can maintain optimal concentration level in soil solution. It was defined that content of heavy metals in three movable forms are represented in the following geochemical units, mg/kg: in acid soluble form – Mn > Zn > Pb > Cu > V > Ni > Co > Cd; in exchangeable form – Mn > Zn > Pb > V > Co = Ni > Cu > Cd; in water soluble form – Mn > Zn > Pb = V > Co > Ni > Cd > Cu. The article presents research results on accumulation intensity and the nature of distribution of gross and mobile heavy metals forms in soil and on their migration in the soil profile. The dominant technogenic geochemical unit was extracted: Cd > Hg > Pb > Cu > Zn > Ni > V > Co > Mn. Landscapes with maximum polyelement contamination have been identified.

The Periodic Table: between the Past and the Future

Possibilities of the Periodic Table exploration are considered. It is shown that the four-valued logic of quantum measurements may be used for the classification of chemical elements. The application of the quantum scales with information on the position of chemical elements with the known sequence numbers inside them allows to find the new aims for metrological investigations and to develop new approaches in the quantum metrology.

Classification of Chemical Elements in the Reaction Cell of ICP-MS Based on the Affinities with Sulfur, Oxygen, and Fluorine

Classification of chemical elements in the reaction cell of an inductively coupled plasma mass spectrometer (ICP-MS) was first reported based on the affinities with multiple elements, i.e. sulfur, oxygen, and fluorine. The data were summarized in the periodic table based on the affinity with each of the three elements mentioned above. An example of the application of the present results was illustrated by analyzing Y and La in the matrix of Sr and Ba, offering apparently improved background equivalent concentration (BEC) and detection limits (DL).

Cognição do ambiente competitivo: um estudo dos construtos mentais utilizados por proprietários de pequenas empresas

A abordagem cognitiva pode ser útil na compreensão dos elementos que permeiam o processo de análise do ambiente competitivo das organizações, por respeitar a complexidade do fenômeno e permitir o entendimento das intenções dos gestores e seus processos de representação do mundo. Coerente com esta proposta, os objetivos deste artigo são identificar e descrever os construtos mentais utilizados pelo dirigente para avaliação de seu ambiente competitivo e determinar se existe associação entre os construtos mentais dos dirigentes de pequenas organizações e contexto de referência e setor de atividade. A metodologia aliou procedimentos qualitativos e quantitativos e diferencia-se por empregar a grade de repertório de Kelly, cuja premissa é o entendimento do mundo associado à categorização de elementos da percepção. A amostra foi composta de 48 empresas industriais de pequeno porte localizadas em Curitiba, PR. Os resultados indicam que o conjunto de construtos utilizados é único para cada dirigente, mas puderam ser notadas comunalidades cognitivas, com a utilização mais frequente de seis construtos. A análise mostra que eles independem do contexto de referência e do setor de atuação. As conclusões permitem inferências acerca dos construtos mentais dos respondentes e seus quadros de referênciapara a avaliação do ambiente competitivo.

Advances in medico-chemical geography in China

We have made progress in medico-chemical geography as follows: the correlative law of organism with geochemical environment; the geochemico-ecological classification of chemical elements; the types of formative cause of biogeochemical provinces in China; the parabolic correlation between contents of iodine in drinking water and prevalence rate of endemic goiter; the discover and proof of the low selenium zone in China; the successive discovery of endemic fluorosis of the types of pollution from burning coal, drinking high fluoride tea and high fluoride table salt from the year 1978; the study on chemical geography of schistosomiasis and the compilation of the Atlas of Endemic Diseases and Their Environments in the People’s Republic of China.

Activation analysis: A basis for chemical similarity and classification

It is shown that activation analysis is especially suited to serve as a basis for determining the chemical similarity between samples defined by their trace element concentration patterns. The general problem of classification and identification is discussed. The nature of possible classification structures and their approriate clustering strategies is considered. A practical computer method is suggested and its application as well as the graphical representation of classification results are given. The possibility for classification using information theory is mentioned. Classification of chemical elements is discussed and practically realized after Hadamard transformation of the concerntration variation patterns in a series of samples.