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Crude petroleum oils are complex mixtures of different compounds (mainly organic), which are obtained from an extensive range of different geological sources. The fluorescence of crude petroleum oils derives largely from the aromatic hydrocarbon fraction, and this fluorescence emission is strongly influenced by the chemical composition (e.g., fluorophore and quencher concentrations) and physical characteristics (e.g., viscosity and optical density) of the oil. The fluorescence spectroscopy (FS) is increasingly used in petroleum technology due the availability of better optical detection techniques, because FS offers high sensitivity, good diagnostic potential, and relatively simple instrumentation. In this work we analyzed crude petroleum at different dilution in Nujol, a transparent mineral oil. The main objective of this work was to verify the possibility to measure crude oil emission spectroscopic without use of volatile solvents. The mixtures of nujol with different -crude oil concentrations were measured with a 10 mm optical path cuvette thus simplifying the fluorescence spectroscopy signal detection. The emission spectra were obtained by exciting the samples with a 400 W Xenon lamp at 350 nm, 450 nm and 532 nm. The emissions of the samples were collected perpendicularly with the excitation axis.

Dairy industry wastewater contains high levels of organic matter, consisting mainly of fat, protein and products of their partial microbial decomposition. In the present study, the use of continuous electrocoagulation is proposed for the primary treatment of dairy wastewater. The electrochemical treatment was carried out in a continuous flow cell with aluminum electrodes. The influence of the voltage, the distance between the electrodes and the hydraulic residence time (HRT) on the process performance was assessed, by measuring the removal of color, turbidity, total organic carbon (TOC) and chemical oxygen demand (COD). The optimum voltage, distance between the electrodes and HRT were 10 V, 1 cm and 90 min, respectively, yielding a current density of 13.3 A.m(-2). Under these conditions, removal of color, turbidity, TOC and COD were 94%, 93%, 65% and 69%, respectively, after a steady state was reached in the continuous flow reactor.

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This paper aim to evaluate the ultrafiltration (UF) process for constituents recovery from whey. Sequences of factorial designs were performed by varying temperature (5 to 40°C) and pressure (1 to 3 bar), to maximize the proteins concentration using membrane of 100kDa in dead end system. Based on the best result new experiments were performed with membrane of 50kDa and 10kDa. With the membrane of 50 the protein retention was about 3 times higher than the membrane of 100kDa. The concentrated obtained by UF membrane of 10kDa, 10°C and 2 bar in laboratory scale showed a mean protein retention of 80 %, greater protein solubility, emulsion stability and the identification of β-lactoglobulins (18.3 kDa) and α-lactalbumin fractions (14.2kDa). Therefore, the use of membrane of 100 and 50kDa are became a industrially recommendable alternatives to concentration of whey proteins, and/or as a previous step to the fractionation of whey constituents using membrane ≤10kDa, aiming at future applications in different areas (food, pharmaceutical, chemical, etc.).

Semiochemicals are chemical compounds that are released by many species as a means of intra- and interspecific communication. Insects have extremely advanced olfactory systems; indeed, they rely on smell when performing many of their main behaviors, such as oviposition, breeding, prey location, and defense. This characteristic of insects implies that semiochemicals could be used for various applications, including in agriculture, where they could be employed along with other tools to control pest insects. The aim of this review is to present the main techniques used and the state of the art in the detection of semiochemicals, focusing on pheromones. In addition to the traditional methods of identifying semiochemicals, such as gas chromatography coupled to a high-resolution detection mode (e.g., flame ionization (FID), electron capture (ECD), photoionization (PID), or mass spectrometry (MS)), other tools are addressed in this review, including sensors and biosensors. While these new technologies may be used under laboratory conditions to improve or complement technologies that are already being used, they are mainly intended for use as new agricultural tools for detecting and controlling pest insects in the field.

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Soybean (Glycine max (L.) Merrill) is a crop of world economic importance. Conventional soybean cultivars, in general are for the oil extraction industries and its subproduct for animal feeding. However, there are some cultivars genetically modified, that present characteristics adapted for different utilizations, including human food. The objective of this work was to evaluate, three soybean cultivars, Vmax (conventional), and BR 257 and 267 (human food uses). Chemical composition was evaluated in grains with tegument (WT) and without tegument (WIT) heat treated (HT) and non-heat treated (NHT). For characterization, it was observed: humidity, proteins, lipids, minerals, nitrogen solubility index (NSI), protein dispersability index (PDI), isoflavones, Kunitz trypsin inhibitor and lipoxygenases. The heat treatment promoted reduction of the protein solubility, reduction of glucosidic and malonyl isoflavones, and of Kunitz trypsin inhibitor, in grains WIT. Lipoxygenases were also inactivated in BRS 267 and Vmax cultivars. Potassium was the mineral present in higher amount in all cultivars. BRS 267 cultivar showed the highest content of protein, but the lowest content of isoflavones. Vmax cultivar showed the highest content of lipids and isoflavones. Heat treatments, although decreasing protein solubility, are necessary for conventional soybeans to improve flavor and to reduce anti nutritional factors. Depending on the objective of soybean utilization, different cultivars and treatments should be applied. Genetic breeding to obtain soybean cultivars with special characters is important to process high quality soybean products.  Index Terms-soybean grains, isoflavones, Kunitz trypsin inhibitor, protein solubility, lipoxygenases, heat treatment I. INTRODUCTION Soybean is one of the protein source most used in the world. However, its organoleptic characteristics are not well accepted for human consumption [1]. Therefore, the development of soybean cultivars more suitable for food utilization is important to attend the demand of the niche market that requires special cultivars with better quality characteristics [2]. Considering the need for soybean products with better flavor and high nutritive value, Brazilian Agriculture Manuscript