Complexos metálicos de cobalto, níquel e cobre com a Pirazina-2-carboxamida e 4- hidrazida ácida piridincarboxílica: síntese e caracterização

This work involved the synthesis, characterization and proposing the molecular structure of coordination compounds involving ligands pyrazine-2-carboxamide (PZA) and 4- hydrazide acidic pyridine carboxylic (INH) and metals of the first transition series (M = Co2+, Ni2+ and Cu2+). For the characterization of the compounds used were analytical techniques such as infrared absorption spectroscopy average (FT-IR) molar conductivity measurements, CHN elemental analysis, EDTA Complexometric, measurement of melting point, X-ray diffraction by powder method, Thermogravimetry (TG) and Differential Thermal Analysis (DTA) and Simultaneous Differential Scanning Calorimetry (DSC). The absorption spectra in the infrared region suggested that the ligand coordination to the metal center occurs through the carbonyl oxygen atom and nitrogen alpha pyrazine ring to those complexes formed with PZA. For INH complexes with metal-ligand coordination is through the carbonyl oxygen and nitrogen of the terminal hydrazide grouping. The conductivity measurements of the complexes in aqueous solution they suggest to all behavior of the type 1:2 electrolytes, and conduct of non-electrolytes in acetonitrile. The results obtained by CHN elemental analysis and EDTA Complexometric allowed to infer the stoichiometry of the compounds synthesized. For all of the complexes obtained was possible to record the melting points, neither of which melted near the melting temperature of the free ligands. The X-ray diffraction showed that the complexes of pyrazinamide exhibited diffraction lines, suggesting that these compounds are crystalline, while compounds of isoniazid, with the exception of cobalt, exhibited diffraction lines, indicating that they are crystalline. The results from the TG-DTA and DSC allowed information regarding the dehydration and thermal decomposition of these complexes

Avaliação oxidativa do biodiesel de pinhão manso em diferentes processos de purificação

The objective of this study was to analyze the oxidative stability of biodiesel from jatropha obtained from different purification processes, three wet processes with different drying (in a vacuum oven, conventional oven and in anhydrous sodium sulfate) and dry (purification with magnesium silicate adsorbent). Raw materials of different qualities (jatropha crop ancient and recent crop) were used. The Jatropha oil was extracted by mechanical extraction and refined. The Jatropha biodiesel was obtained by the transesterification reaction in ethyl route using alkaline catalysis. The biodiesel samples were characterized by analysis of water content, carbon residue, Absorption Spectroscopy in the Infrared Region and Thermogravimetry. Thermogravimetric curves of purified PUsv* PUsq* and had higher initial decomposition temperatures, indicating that the most stable, followed by samples PU* and PUSC*. Besides the sample SP* is a smaller initial temperature, confirming the sample without purification to be less thermally stable. The percentage mass loss of the purified samples showed conversion of about 98.5%. The results of analyzes carbon residue and infrared suggested that contamination by impurities is the main factor for decreased oxidative stability of biodiesel. The oxidative stability was assessed from periodic monitoring, using the techniques of Rancimat, peroxide index, acid value and Pressurized Differential Scanning Calorimetry. Samples of biodiesel from jatropha which showed better oxidative stability were of the best quality raw material and wet scrubbing: PUsq* with dry chemical, using anhydrous sodium sulfate and PUsv* with vacuum drying, which had oxidative stability 6 hours in Rancimat time 0 days, within the limits established by the Technical Regulation No. 4/2012 of the ANP, without the addition of antioxidant, suggesting that these procedures the least influence on the oxidative stability of biodiesel

Estudo da influência do biodiesel de mamona como aditivo antioxidante para o biodiesel de girassol e soja

Biodiesel is a fuel made up by mono-alkyl-esters of long chain fatty acids, derived from vegetable oils or animal fat. This fuel can be used in compression ignition engines for automotive propulsion or energy generation, as a partial or total substitute of fossil diesel fuel. Biodiesel can be processed from different mechanisms. Transesterification is the most common process for obtaining biodiesel, in which an ester compound reacts with an alcohol to form a new ester and a new alcohol. These reactions are normally catalyzed by the addition of an acid or a base. Initially sunflower, castor and soybean oil physicochemical properties are determined according to standard test methods, to evaluate if they had favorable conditions for use as raw material in the transesterification reaction. Sunflower, castor and soybean biodiesel were obtained by the methylic transesterification route in the presence of KOH and presented a yield above 93% m/m. The sunflower/castor and soybean/castor blends were studied with the aim of evaluating the thermal and oxidative stability of the biofuels. The biodiesel and blends were characterized by acid value, iodine value, density, flash point, sulfur content, and content of methanol and esters by gas chromatography (GC). Also studies of thermal and oxidative stability by Thermogravimetry (TG), Differential Scanning Calorimetry High Pressure (P-DSC) and dynamic method exothermic and Rancimat were carried out. Biodiesel sunflower and soybean are presented according to the specifications established by the Resolution ANP no 7/2008. Biodiesel from castor oil, as expected, showed a high density and kinematic viscosity. For the blends studied, the concentration of castor biodiesel to increased the density, kinematic viscosity and flash point. The addition of castor biodiesel as antioxidant in sunflower and soybean biodiesels is promising, for a significant improvement in resistance to autoxidation and therefore on its oxidative stability. The blends showed that compliance with the requirements of the ANP have been included in the range of 20-40%. This form may be used as a partial substitute of fossil diesel

Estudo integrado do potencial fitorremediador da Eichhornia crassipes em ambientes naturais e sua utilização para obtenção de extratos proteicos

This study aimed to analyze the phytoremediation potential of Eichhornia crassipes in natural environments, optimize the extraction process of crude protein from plant tissue and, obtain and characterize this process in order to determine its viability of use instead of the protein sources of animal and/or human feed. For this, it has been determined in Apodi/Mossoró river water the concentration of ammonium ions, nitrite, nitrate, calcium, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, aluminum, cádmium, lead, and total chromium; It was determined in plant tissue of aquatic macrophytes of Eichhornia crassipes species present in Apodi/Mossoró River the moisture content, ash, calcium, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, aluminum, cadmium, lead, total chromium, total nitrogen and crude protein. It was also determined the translocation factor and bioaccumulation of all the quantified elements; It was developed and optimized the extraction procedure of crude protein based on the isoelectric method and a factorial design 24 with repetition; It was extracted and characterized the extract obtained by determining the moisture content, ash, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, cadmium, total nitrogen and crude protein. And finally, it was also characterized the protein extract using Thermogravimetric Analysis (TG), Derived Thermogravimetric (DTG), Differential Scanning Calorimetry (DSC), Infrared Spectroscopy (FT-IR) and jelly-like electrophoresis of polyacrylamide (SDS -PAGE) to assess the their molecular weights/mass. Thus, from the results obtained for the translocation and bioaccumulation factors was found that the same can be used as phytoremediation agent in natural environments of all quantified elements. It was also found that the developed method of extraction and protein precipitation was satisfactory for the purpose of the work, which gave the best conditions of extraction and precipitation of proteins as: pH extraction equal to 13.0, extraction temperature equals 60 ° C, reaction time equals to 30 minutes, and pH precipitation equals to 4.0. As for the extract obtained, the total nitrogen and crude protein were quantified higher than those found in the plant, increasing the crude protein content approximately 116.88% in relation to the quantified contente in the vegetal tissue of macrophyte. The levels of nickel and cadmium were the unique that were found below the detection limit of used the equipment. The electrophoretic analysis allowed us to observe that the protein extract obtained is composed of low polypeptide chains by the molecular and phytochelatins, with 6 and 15 kDa bands. Analysis of TG, DTG, DSC and FT-IR showed similarities in protein content of the obtained extracts based on different collection points and 9 parts of the plant under study, as well as commercial soy protein and casein. Finally, based on all these findings, it was concluded that the obtained extract in this work can be used instead of the protein sources of animal feed should, before that, test its digestibility. As human supplementation, it is necessary to conduct more tests associated with the optimization process in the sense of removing undesirable components and constant monitoring of the water body and the raw material used

Resting energy expenditure and carbohydrate oxidation are higher in elderly patients with COPD: a case control study

Background: Elderly patients with chronic obstructive pulmonary disease (COPD) usually have a compromised nutritional status which is an independent predictor of morbidity and mortality. To know the Resting Energy Expenditure (REE) and the substrate oxidation measurement is essential to prevent these complications. This study aimed to compare the REE, respiratory quotient (RQ) and body composition between patients with and without COPD.Methods: This case-control study assessed 20 patients with chronic obstructive pulmonary disease attending a pulmonary rehabilitation program. The group of subjects without COPD (control group) consisted of 20 elderly patients attending a university gym, patients of a private service and a public healthy care. Consumption of oxygen (O-2) and carbon dioxide (CO2) was determined by indirect calorimetry and used for calculating the resting energy expenditure and respiratory quotient. Body mass index (BMI) and waist circumference (WC) were also measured. Percentage of body fat (%BF), lean mass (kg) and muscle mass (kg) were determined by bioimpedance. The fat free mass index (FFMI) and muscle mass index (MMI) were then calculated.Results: The COPD group had lower BMI than control (p = 0.02). However, WC, % BF, FFMI and MM-I did not differ between the groups. The COPD group had greater RQ (p = 0.01), REE (p = 0.009) and carbohydrate oxidation (p = 0.002).Conclusions: Elderly patients with COPD had higher REE, RQ and carbohydrate oxidation than controls.

Metabolismo de repouso de mulheres pós-menopausadas submetidas a programa de treinamento com pesos (hipertrofia)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Caracterização físico-química da mucilagem de inhame liofilizada

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Glass transition temperature of hard chairside reline materials after post-polymerisation treatments

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Continuous and gradual photo-activation methods: influence on degree of conversion and crosslink density of composite resins

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Biodegradation of blend films in soil and soil with chorume. I. PVC/PCL

Blends of synthetic and biodegradable polymers can be important in attaining material plastic degradation in the environment. Biodegradation using soil and chorume (liquid waste from landfill) microorganisms is a promising area these days. This paper intends to study the PVC/PCL blend degradation in soil using aerobic biodegradation (Bartha respirometer). The morphology and structural changes of the blends were studied by FTIR, scanning electron microscopy, differential scanning calorimetry and contact angle measurements. Blend films prepared by the casting of dichloroethane solutions were buried in a Bartha respirometer containing soil and soil plus chorume and kept there for 120 days. During this time CO2 evolution was measured from time to time. The results showed that PCL films degrade faster than PVC/PCL and PVC films.

Molecular, kinetic, thermodynamic, and structural analyses of Mycobacterium tuberculosis hisD-encoded metal-dependent dimeric histidinol dehydrogenase (EC 1.1.1.23)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência da geometria e umidade de colunas de solo na biodegradação de filmes de PCL

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Biodegradation of the Films of PP, PHBV and Its Blend in Soil

Films of poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and poly(propylene) (PP), PP/PHBV (4:1), blends were prepared by melt-pressing and investigated with respect to their microbial degradation in soil after 120 days. Biodegradation of the films was evaluated by Fourier transform infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction. The biodegradation and/or bioerosion of the PP/PHBV blend was attributed to microbiological attack, with major changes occurring at the interphases of the homopolymers. The PHBV film was more strongly biodegraded in soil, decomposing completely in 30 days, while PP film presented changes in amorphous and interface phase, which affected the morphology.

The influence of UV-C irradiation on the properties of thermoplastic starch and polycaprolactone biocomposite with sisal bleached fibers

The effect of UV-C irradiation of the TPS and PCL biocomposites with sisal bleached fibers was investigated. The biocomposite was UV-C irradiated at room temperature under air atmosphere. The structural and morphological changes produced when the films were exposed to UV irradiation for 142 h, were monitored using Scanning Electron Microscopy (SEM), Mechanical Tensile Tests, Differential Scanning Calorimetry (DSC), X-ray diffraction, Thermogravimetric analysis (TGA), and Fourier transform infra-red analysis (FTIR). Addition of 5-10% fibers in composites exhibited improved mechanical and thermal properties attributed to more efficient dispersibility of fiber in the matrix and good compatibility between fibers and the matrix polymer, however, after irradiated, the tensile properties decreased due to chain scission. The samples of irradiated PCL and IFS showed crystallinity increase, whereas the blend and composites showed a decrease in crystallinity. The DSC and X-ray diffraction studies suggested interaction between polymers in the blend via carboxyl groups in thermoplastic starch-PCL and hydroxyl groups in fibers. (C) 2011 Elsevier Ltd. All rights reserved.

Action of soil microorganisms on PCL and PHBV blend and films

Poly(hydroxybutyrate-co-valerate) (PHBV) and poly(epsilon-caprolactone) (PCL) PCL/PHBV (4:1) blend films were prepared by melt-pressing. The biodegradation of the films in response to burial in soil for 30 days was investigated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetry (TG). The PHBV film was the most susceptible to microbial attack, since it was rapidly biodegraded via surface erosion in 15 days and completely degraded in 30 days. The PCL film also degraded but more slowly than PHBV. The degradation of the PCL/PHBV blend occurred in the PHBV phase, inducing changes in the PCL phases (interphase) and resulting in an increase of its crystalline fraction.