37 research outputs found
Processed Drug Classification and Temporal Analysis by Technical Chemometrics for Quality Controlling Using Spectroscopy of FT-IR and X-Ray Diffraction
The aim of the present study was to analyze samples of the industrialized drugs, topiramate and levothyroxine sodium by FT-IR and XRD for a period of five months. Cluster chemometrics and principal component analysis were used to plot the samples in this time series and to compare FT-IR and XRD techniques for drug classification. By means of the chemometric analyzes of the time series it was possible to separate the two drugs in different groups satisfactorily. The analysis of PCA showed great homogeneity between samples, explaining 99.8% of the variability of the data, confirming the integrity of the sample matrices during the period. The comparison between FT-IR and XRD techniques showed great efficiency for drug classification. The FT-IR technique explained 99.9% of the variability of the data from the sample set while the XRD technique explained 98.6%. Given the above, you can prove the integrity of topiramate medication and levothyroxine sodium over time by means of spectroscopic analyzes associated with chemometric analysis, as well as prove the efficiency of mid-infrared techniques, and diffraction X-ray coupled to chemometric analysis Quality control in the pharmaceutical segment.
DOI: http://dx.doi.org/10.17807/orbital.v10i7.113
MULTIVARIATE ANALYSIS FOR CLASSIFICATION OF DENDROMETRIC AND ENERGETIC VARIABLES OF Eucalyptus benthamii
The objective of this study was to evaluate dendrometric data and energetic properties of E. benthamii, based on evaluations in plantations of different ages and regions of production, in Guarapuava-PR, through multivariate statistical analysis. The data refer to three regions (R1, R2 and R3) and ages (5, 6 and 7 years), were submitted to multivariate techniques: factor analysis, analysis of the main components and analysis of hierarchical grouping. The reduction in the dimensionality of the data was found containing only 5 attributes of the initial 13, which are (average DBH, average height, volume per hectare, basic density of wood and energy density), associated with two main components, capable of representing 95.22% of the data variance. The plantations in the R1 region with seven years of age showed excellent energetic properties, while the plantations in R2 region with seven years and R3 region with six years represent more productive areas, evaluated by dendrometric variables. It was also observed that plantations with older age and higher basic wood density have higher quality for energy use. It can be concluded that the cluster analysis was adequate to efficiently stratify regions and ages with higher and lower productivity, as well as those with better energetic properties
DETERMINATION OF E. benthamii PROPERTIES BY INFRARED SPECTROSCOPY AND PLS
Considering the interest in the Eucalyptus benthamii species and the search for alternatives to determine some physical properties in a fast and reliable way, the objective of this study was to build multivariate calibration models through the near infrared spectroscopy (NIR) technique and partial least squares regression (PLS) for wood basic density (BD) and chip moisture (U). Trees were sampled in five diametric classes and used to evaluate DB, as a function of 3 ages and 3 production regions of E. benthamii. We considered only plantations at 7 years of age in the harvest phase and chip samples considering pre-defined intervals of ten days, from the date of tree harvest to 90 days, in two seasons of the year (winter and spring) for moisture analysis. For DB and U, NIR models were calibrated and validated using partial least squares (PLS) regression. Calibration models were evaluated by correlation coefficients (R²), root mean square error (RMSE), and variance performance ratio (RPD). The models for near infrared (NIR) spectroscopy showed R² values ranging from 0.60 to 0.68 for basic density and 0.72 for moisture. The best model for DB observed was the one that considered only the DAP samples. It was concluded that the NIR technique was suitable for estimating the properties of moisture and wood density in this evaluated species, E. benthamii.
Remaining Capacity Estimation of Lead-acid Batteries Using Exponential Decay Equations
The precise capacity estimation of batteries can extend their lifespan and is necessary to ensure reliability and safety of operation. Many methods have been developed with this objective in the last decades. However, there is still research for more accurate and less complex methods in order to estimate the state of charge of operating batteries. This article presents exponential decay equations that model the behavior of the battery capacity drop with the discharge current. Experimental data for different application batteries showed that these equations have a superior accuracy compared to the empirical Peukert equation. Their parameters are dimensionally coherent and make the characterization and categorization of batteries possible, besides, they give insights about the behavior of the electrodes under different discharge rates. Due to the low complexity and easy adaptability to the currently employed methods, these equations can be easily employed in battery management systems without the need for great computational power.
DOI: http://dx.doi.org/10.17807/orbital.v13i5.155
Data Preprocessing and Homogeneity: The Influence on Robustness and Modeling by PLS Via NIR of Fish Burgers
Fish burgers as new products require their shelf life investigated. Sensory results usually do not follow a homogeneous profile, as it measures human perception. Once the sensory and physicochemical monitoring of the shelf life takes time and considerable investment, the Near Infrared spectroscopy comes as a fast instrumental technique, which can access multiple parameters from the sample at the same time. In order to replace traditional methods improving mathematical modeling, the objective of this study is the estimation of the data preprocessing and homogeneity (Kolmogorov–Smirnov) influence in the quality parameters of Partial Least Squares modeling. Calibration and validation models were evaluated by means of correlation coefficient, Rank, robustness and Residual Prediction Deviation. All the preprocessing available on the software Opus Lab® were tested and compared. 72 readings/8 samples of refrigerated grass carp burgers originated the data regarding its water activity, rancid taste, pH and reactive substances of thiobarbituric acid results. The preprocessing methods accessible were Standard Normal Variate, Multiplicative Scatter Correction, 2nd derivative, 1st derivative, Straight Line Subtraction and Min/Max. Each chosen preprocessing generated a model with different parameters. The homogeneity of data proved to have a direct influence on the robustness, confirming the challenge to fit sensory results in Partial Least Squares prediction models. New possibilities to investigate meat products were shown.
DOI: http://dx.doi.org/10.17807/orbital.v11i6.123
Remaining Capacity Estimation of Lead-acid Batteries Using Exponential Decay Equations
The precise capacity estimation of batteries can extend their lifespan and is necessary to ensure reliability and safety of operation. Many methods have been developed with this objective in the last decades. However, there is still research for more accurate and less complex methods in order to estimate the state of charge of operating batteries. This article presents exponential decay equations that model the behavior of the battery capacity drop with the discharge current. Experimental data for different application batteries showed that these equations have a superior accuracy compared to the empirical Peukert equation. Their parameters are dimensionally coherent and make the characterization and categorization of batteries possible, besides, they give insights about the behavior of the electrodes under different discharge rates. Due to the low complexity and easy adaptability to the currently employed methods, these equations can be easily employed in battery management systems without the need for great computational power.
DOI: http://dx.doi.org/10.17807/orbital.v13i5.155
Data Preprocessing and Homogeneity: The Influence on Robustness and Modeling by PLS Via NIR of Fish Burgers
Fish burgers as new products require their shelf life investigated. Sensory results usually do not follow a homogeneous profile, as it measures human perception. Once the sensory and physicochemical monitoring of the shelf life takes time and considerable investment, the Near Infrared spectroscopy comes as a fast instrumental technique, which can access multiple parameters from the sample at the same time. In order to replace traditional methods improving mathematical modeling, the objective of this study is the estimation of the data preprocessing and homogeneity (Kolmogorov–Smirnov) influence in the quality parameters of Partial Least Squares modeling. Calibration and validation models were evaluated by means of correlation coefficient, Rank, robustness and Residual Prediction Deviation. All the preprocessing available on the software Opus Lab® were tested and compared. 72 readings/8 samples of refrigerated grass carp burgers originated the data regarding its water activity, rancid taste, pH and reactive substances of thiobarbituric acid results. The preprocessing methods accessible were Standard Normal Variate, Multiplicative Scatter Correction, 2nd derivative, 1st derivative, Straight Line Subtraction and Min/Max. Each chosen preprocessing generated a model with different parameters. The homogeneity of data proved to have a direct influence on the robustness, confirming the challenge to fit sensory results in Partial Least Squares prediction models. New possibilities to investigate meat products were shown.
DOI: http://dx.doi.org/10.17807/orbital.v11i6.123
COLORAÇÕES ANÔMALAS EM DIDELPHIS ALBIVENTRIS (DIDELPHIMORPHIA, DIDELPHIDAE) EM UM FRAGMENTO DE MATA ATLÂNTICA DE INTERIOR NO OESTE DO ESTADO DO PARANÁ, BRASIL
Apresenta-se um registro de colorações anômalas, provável caso de leucismo, em dois indivíduos de Didelphis albiventris pertencentes a uma mesma população em um fragmento de Mata Atlântica de Interior, no oeste do estado do Paraná, contribuindo desta maneira a história natural desta espécie
Seasonal Effect on Milk Composition, Somatic Cell Content and Milk Coagulation Properties of Italian Holstein-Friesian Cows
This study investigated the seasonal effect on composition, somatic cell content and coagulation properties of bovine milk during two different periods of the year (summer and autumn). 592 samples of raw milk from Italian Holstein-Friesian cows from different locations in the Veneto region, Italy, were collected. The samples were submitted to the following analyses: fat, protein, casein and lactose percentages and pH by infrared spectroscopy; somatic cell counting by optical fluorescence and milk coagulation properties expressed in rennet coagulation time (RCT, min) and curd firmness or consistency 30 minutes after the addition of rennet (a30, mm) by lactodinamography. The index of the aptitude of milk to coagulate (IAC) was also determined from the lactodinamographic parameters that were obtained. To verify the environmental conditions, the temperature humidity index (THI) was calculated for each collection period. No significant difference (p <0.05) was observed between protein, casein, lactose and pH in the samples collected in the summer and the autumn. However, the results for somatic cells, RCT, a30 and IAC were significantly different, with lower results in the summer. Over all the total samples analysed, 41.2% showed a milk that did not coagulate in the 30 minutes, with a higher percentage for samples collected in the summer and during this period presented lower results to of RCT, a30 and IAC; the THI values, as expected, were higher in the summer than in the autumn. The THI presented statistically different means (p <0.05), which were 73.24 in the summer and 57.43 in the autumn. Milk with this characteristic is not suitable for cheese production; however, it is suitable to produce fluid milk, or for other derivatives where enzymatic coagulation is not part of the process