A5013940523- Analytical chemistry methods development
- Composting and Vermicomposting Techniques
- Pesticide Residue Analysis and Safety
- Heavy metals in environment
- Mass Spectrometry Techniques and Applications
- Mercury impact and mitigation studies
- Electrochemical Analysis and Applications
- Radioactive element chemistry and processing
- Recycling and Waste Management Techniques
- Environmental Toxicology and Ecotoxicology
- Chemical Synthesis and Characterization
- Advanced materials and composites
- Marine Bivalve and Aquaculture Studies
- Aquatic Ecosystems and Phytoplankton Dynamics
- Radiation Effects and Dosimetry
- Microwave-Assisted Synthesis and Applications
- Radioactivity and Radon Measurements
- Orthopaedic implants and arthroplasty
- Diatoms and Algae Research
- Heavy Metal Exposure and Toxicity
- Advanced Chemical Sensor Technologies
- Environmental and Social Impact Assessments
- Heavy Metals in Plants
- Electrokinetic Soil Remediation Techniques
- Agricultural Science and Fertilization
Universidade Federal de São Carlos
2013-2025
Brazilian Agricultural Research Corporation
2009-2010
Universidade de São Paulo
2009-2010
Universidade Federal de Viçosa
2006-2007
Chemical and spectroscopic methods were used to characterize organic matter transformations during the composting process. Four different residue mixtures studied: P1--garden trimmings (GT) only, P2 - GT plus fresh cattle manure, P3--GT orange pomace P4--GT filter cake. The thermophilic phase was not reached in P1 compost, but P2, P3 P4 composts showed all three typical process phases. CEC/C ratio stabilized after 90 days, while C/N ash content 60 days. increasing E(4)/E(6) indicated...
Advancements in sample preparation for performing trace analysis of inorganic analytes are coming from the dissemination microwave-assisted procedures, but there is still room improvements by looking simple and easily applied procedures. Recently it was proposed a new approach called single reaction chamber with capability digestions at high pressures temperatures using vials racks. This limitation former cavity microwave ovens closed vessels. It demonstrated here that use allows...
The feasibility of inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) to overcome polyatomic interferents in severely affected isotope determination is demonstrated here.
Microalgae can be exposed to a gradual copper (Cu) increase over wide concentration range in the environment, but most studies focus on punctual increases. This research investigates effects of quasi-continuous Cu exposure Kirchneriella obesa, providing new insights thresholds healthy and unhealthy cellular responses. Photosynthesis, cell density, biomolecules were measured at 20 free levels, from environmental toxic (3x10−9 4 x 10−5 mol L−1). Using nonlinear Bayesian regression models, we...
Trace element determination exploiting MS/MS mode and reaction with oxygen gas.
A multinebulizer based on the Flow Blurring® nebulization principle for analysis of acid digested samples using on-line standard addition calibration in ICP-OES and ICP-MS.
The combination of dilute nitric acid digestion followed by recovery the digests, represents steps towards green chemistry approaches: “reduce use, recycle and reuse”, strictly following major recommendations.
Nowadays, microwave-assisted procedures using closed vessels with thermal, chemical, and mechanical resistance are the state-of-the-art for efficient digestion of samples. Safety issues related to sample reactivity should be considered analytical throughput is also a critical parameter. The choice specific vessel target application not trivial simple experiments presented here rice flour bovine liver samples illustrate effects design on performance. Despite same heating program, residual...
Microwave-assisted sample digestion using closed vessels is becoming the standard for trace analysis because contamination and losses can be better controlled. Gases are generated during there an increment of internal vessel pressure. Consequently, venting may occur depending on design maximum pressure it stand for. In present work was observed that possible to allow without losing volatile analytes, such as As, when properly controlling heating chemical conditions. Recoveries As in...
COMPOSTING.In this work was studied composts and their humic acids (HA) to evaluate the use of EPR in monitoring humification.It observed increase concentration organic free radical (OFR) all composts, but L1 more significant than L2 L3.Research detailed showed that lignin is main source OFR.Then determination these radicals material nature contains high amount isn't a good indicator monitor humification process composting yes fraction HA composts.
The fatty acid methyl ester and triacylglyceride content of the oils seven microalgae species were analyzed by gas chromatography in order to predict influence on physicochemical properties biodiesel. Among examined, Chlorella minutissima Arthrospira platensis showed biodiesel production potential, while acids from vulgaris, Cyclotella sp., Cylindrotheca closterium, Entomoneis alata, A. have great economic values, with application pharmaceutical food industries. oxidative stability produced...
FLAME ATOMIC ABSORPTION SPECTROMETRY (FAAS).Simple and sensitive procedures for the extraction/ preconcentration of molybdenum based on vortex-assisted solidified floating organic drop microextraction (VA-SFODME) cloud point combined with flame absorption atomic spectrometry (FAAS) discrete nebulization were developed.The influence sensitivity processes was studied.An injection volume 200 µL resulted in a lower relative standard deviation both procedures.Enrichment factors 31 67 limits...
In this study, two laser-based techniques, laser-induced breakdown spectroscopy (LIBS) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) were used for analytical signal evaluation of Ti, Al, V investigation possible harmful elements eventually present as minor in Ti alloys.Due to the lack certified reference materials, samples also analyzed by wavelength dispersive X-ray fluorescence (WDXRF) inductively plasma optical emission (ICP OES) after microwave-assisted...