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Chapter and Conference Paper
A MCDA/GIS-Based Approach for Evaluating Accessibility to Health Facilities
Access to health care services is a key concept in the formulation of health policies to improve the population’s health status and to mitigate inequities in health. Previous studies have significantly enhance...
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Article
Sedentary behavior and compensatory mechanisms in response to different doses of exercise—a randomized controlled trial in overweight and obese adults
To examine compensatory changes in sedentary behavior (SB) and light-intensity physical activities (LIPA) in response to a 22-week exercise training program in overweight/obese adults; and to determine if diff...
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Article
Structural chemistry and the transcendental numbers \(\upphi \) , e and \(\uppi \)
Certain number theory relations that emerge from considerations of the topological character of several patterns taken from structural chemistry are reviewed. These relations define the products ...
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Article
Exocyclobutadieneite
This communication describes a novel structural-type that could be the basis for a potentially new allotrope of C. The novel structural-type is called “exocyclobutadieneite”, and it is thus named for the 1,3-d...
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Article
Thermal decomposition reaction of 3,3,6,6-tetramethyl- 1,2,4,5-tetroxane in 2-methoxy- ethanol solution
The thermal decomposition study of 3,3,6,6-tetramethyl-1,2,4,5-tetroxane (acetone cyclic diperoxide) was carried out in 2-methoxyethanol solution in the 130-166 °C temperature range. The overall reaction follo...
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Article
Hsichengia: A 4,6-connected trigonal structural pattern in space group P3m1
A novel 4,6-connected network, called Hsichengia, is described. The novel network lies in the trigonal space group P3m1 (no. 156), with a = b = 3.447 Å and c = 12.948 Å; these lattice parameters were derived assu...
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Article
Thermal decomposition of formaldehyde diperoxide in aqueous solution
Thermal decomposition of formaldehyde diperoxide (1,2,4,5-tetraoxane) in aqueous solution with an initial concentration of 6.22 × 10−3 M was studied in the temperatures range from 403 to 439 K. The reaction was f...
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Article
Comparative analysis of complexation of pesticides (fenitrothion, methylparathion, parathion) and their carboxylic ester analogues by β-cyclodextrin. Theoretical semiempirical calculations
The complexation by β-cyclodextrin (β-CD) of three organophosphorus pesticides, fenitrothion, parathion and methylparathion, and of their carboxylic ester analogues was analyzed using PM3 and molecular mechani...
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Article
Mass spectrometry as a tool for studying tautomerism
The review contains new data on tautomerism of organic compounds belonging to different classes, which were obtained by mass spectrometry and confirmed by quantum-chemical calculations.
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Article
Theoretical studies on the structure and spectroscopic properties of pseudohalides
Pseudohalogen-containing compounds have attracted significant interest among nonmetal chemists and theorists, not only owing to their potential use in various fields but also due to difficulties in their exper...
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Article
Catalytic effect of cuprous ions on the thermal decomposition of 3,3,6,6-tetramethyl-1,2,4,5-tetraoxane in methanol solution
Thermal decomposition of 3,3,6,6-tetramethyl-1,2,4,5-tetraoxane was examined in methanol solution (1.69×10−2 M) containing cuprous ions (5.05×10−7 M) in the temperature range from 130 to 166°C using UV spectrosco...
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Article
New Yorkite: A 4,8-connected tetragonal structural pattern in the space group P4/mmm
A novel hypothetical 4,8-connected tetragonal crystalline structure with a ternary stoichiometry AB2C2 is described. The novel pattern belongs to the space group P4/mmm (no. 123). The structure includes novel 8-c...
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Article
Kentuckia: A 4,6,8-connected tetragonal structural pattern in space group P4/nmm
The crystal structure of a novel, hypothetical 4,6,8-connected tetragonal structural pattern with the ternary stoichiometry ABC 2 is described. The novel pattern belongs to the P4/nmm space group (no. 129). It po...
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Article
QSPR Modeling of Gibbs Free Energy of Organic Compounds by Weighting of Nearest Neighboring Codes
We examine the encoding of chemical structure of organic compounds by Labeled Hydrogen-Filled Graphs (LHFGs). Quantitative Structure-Property Relationships (QSPR) for a representative set of 150 organic molecu...
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Article
QSPR modeling the aqueous solubility of alcohols by optimization of correlation weights of local graph invariants
Optimization of correlation weights of local graph invariants is an approach to model molecular properties and/or activities of chemical or/and biological interest. The essence of the approach may be described...
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Article
Molecular Mechanics Study of Cyclic and Unsymmetrical Diborane(4) Compounds
The results of a theoretical study on the structure of some diborane(4) compounds are presented in order to analyze the ralative stabilities of the 1,1- and 1,2-isomers. Using the molecular mechanics method, c...
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Article
Improved QSAR Analysis of the Toxicity of Aliphatic Carboxylic Acids
The results of a QSPR study of the toxicity of carboxylic acids in aqueous solution are reported. The molecular set comprises 35 carboxylic acids with the corresponding pK a values in water. The set of molecular ...
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Chapter and Conference Paper
Leishmania Species in Two Regions of Paraná, Brazil: Biochemical Characterization by Isoenzyme Electrophoresis
Cutaneous leishmaniasis is present in two different regions of the State of Parana, (South of Brazil): in the Northern area and the Ribeira River Valley. In 1994 there was an outbreak with a total of 1395 leis...
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Article
Prediction of Critical Temperatures and Critical Pressures of Some Industrially Relevant Organic Substances from Rather Simple Topological Descriptors
The simplest topological molecular parameters were applied to predict critical temperatures and critical pressures in terms of the QSAR/QSPR theory. Through the development of four different calculation scheme...
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Article
Theoretical Study of the trans-3,6-Dimethoxy-1,2,4-trioxane Molecule
The molecule of trans-3,6-dimethoxy-1,2,4-trioxane has been studied by the semiempirical molecular orbital AM1 and PM3 methods. The numerical results of the structural study have been analyzed in terms of several...
