Chemical characterization of agricultural waste found in communities Lajedo, Amargosa and Vira Beju in Petrolina-PE during the drought period.

The present study was carried out in order to chemically characterize the agricultural waste generated in three communities in Projeto Pontal in period of water deficit, between August and November 2013

Genome-inspired molecular identification in organic matter via Raman spectroscopy

Rapid, non-destructive characterization of molecular level chemistry for organic matter (OM) is experimentally challenging. Raman spectroscopy is one of the most widely used techniques for non-destructive chemical characterization, although it currently does not provide detailed identification of molecular components in OM, due to the combination of diffraction-limited spatial resolution and poor applicability of peak-fitting algorithms. Here, we develop a genome-inspired collective molecular structure fingerprinting approach, which utilizes ab initio calculations and data mining techniques to extract molecular level chemistry from the Raman spectra of OM. We illustrate the power of such an approach by identifying representative molecular fingerprints in OM, for which the molecular chemistry is to date inaccessible using non-destructive characterization techniques. Chemical properties such as aromatic cluster size distribution and H/C ratio can now be quantified directly using the identified molecular fingerprints. Our approach will enable non-destructive identification of chemical signatures with their correlation to the preservation of biosignatures in OM, accurate detection and quantification of environmental contamination, as well as objective assessment of OM with respect to their chemical contents

Holographic characterization of chain photopolymerization

A holographic characterization technique is developed in accordance with a general photopolymerization model. The technique allows detailed quantification of the chemical parameters, including their variation from the Trommsdorff effect. The holographic procedure is especially suited for studying the diffusion of the chemical reactants

Chemical markers for the characterization of bioaerosol

Bioaerosol is commonly defined as aerosolized particles, with a biological origin, spread into the air by a variety of abiotic and biotic mechanisms. The size of bioaerosol can range from several nanometers to a few hundred micrometres in aerodynamic diameter. Examples of bioaerosols include fungal and bacterial spores/cells, fungal hyphae, pollen, viruses and amoebae, algae, lichen, archaea, aggregates of these particles, and fragments of larger organisms including leaf litter, skin scales, animal and plant debris. Metabolites and excreta are also included in this topic. In these last years the knowledge about indoor and occupational bioaerosol exposure and related diseases has significantly increased. Biological particles have been linked to mucous membrane irritation, allergy, asthma, inflammatory lung diseases, hypersensitivity pneumonitis and so on . The use of biomarkers as a tool for the determination of bioaerosol has often been suggested. The basis of this approach is that bioaerosol components contain chemical compounds that can be used as markers of larger and/or bioactive structures. The main objective of our research is the identification and quantitation of dipicolinic and muramic acids, ergosterol, poliols, amino acids and proteins as markers of bacterial, fungal spores/cells and generic bioaerosol, in both indoor and outdoor airborne particulate matter. To achieve this purpose, methods of extraction and analysis by chromatographic techniques coupled to mass spectrometry of different classes of compounds from particulate matter of different size (ultrafine, fine and coarse), collected in proper sampling campaigns, have been developed

Surface-micromachined Ta–Si–N beams for use in micromechanics

Realization and characterization of free-standing surface-microstructures based on Ta-Si-N films are presented. Due to their significant physical and chemical properties, such ternary films are promising candidates for application in microelectromechanical devices

Polymer optical waveguide based n wet-chemical fabrication process

The wet-chemical fabrication process of BenzoCyclobutene (BCB 4024-40) polymer waveguides are described. The method of prism coupling is adopted in the characterization process of the polymer film. A cost effective chemical etching technique is used in the waveguide fabrication process to take advantage of the photosensitive nature of the polymer. The waveguide loss is measured using the conventional cut back method which results on an average loss of 3.5 dB/cm

Note on PI and Szeged indices

In theoretical chemistry molecular structure descriptors are used for modeling physico-chemical, pharmacological, toxicologic, biological and other properties of chemical compounds. In this paper we study distance-based graph invariants and present some improved and corrected sharp inequalities for PI, vertex PI, Szeged and edge Szeged topological indices, involving the number of vertices and edges, the diameter, the number of triangles and the Zagreb indices. In addition, we give a complete characterization of the extremal graphs.Comment: 10 pages, 3 figure