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Item Análisis estructural y supramolecular del compuesto (e)-3',6'-dihidroxi-2-((pyridina-2-yl metileno) amino) spiro[isoidolina-1,9'-xanteno]-3-ona(Universidad Santiago de Cali, 2019) Cardona Restrepo, Camila; Fernando D¨vries, RichardThe crystalline structure of the compound (E) -3 ',6'-dihydroxy-2-((pyridine-2-and methylene) amino) spiro [iso-idoline-1,9'-xanthene] -3-one was solved and refined, using single crystal X-ray diffraction data. It was found that the compound crystallized in the triclinic P-1 space group. its unit cell present two molecules per asymmetric unit, which correspond to molecular conformers. Moreover, an analysis to determine the intermolecular interactions from the crystalline system was performed. It was observed that the crystal packing is formed mainly by hydrogen interactions type O-H••• N, and C-H•••O. Finally, the supramolecular interactions of the dimer were quantified using fingerprint plots, obtaining values of 41.4%, 12.9%, 11.1% and 10.4% for interactions type H•••H, C•••H, O•••H, H•••C respectively. The aforementioned diagrams were compared with the obtained for structurally similar molecules; their forms confirmed the differences at the supramolecular level of the compounds analyzed. With this project, it was possible to determine the structural and supramolecular characteristics of the compound. In addition, were acquired the basic concepts related to crystallography and supramolecular chemistry, both at a theoretical and experimental level.Item Aplicación de la ecuación de Schrödinger en el estudio del movimiento de moléculas diatómicas(Universidad Santiago de Cali, 2019) Bueno Barbosa, Douglas Andrés; Parada Valencia, AlexanderUnderstanding the physiochemical phenomenon at the subatomic level is very important in order to know the behaviour of the matter these energy scales. It is necessary to use the Schrödinger equation in the order to describe chemical and physically the molecules. Throughout of the development of this work, we addressed the study of the Schrödinger equation and applications in the movement of diatomic molecules. The interaction potential is described by this equation, as well as the translational, rotational and vibrational energies of each molecule. Likewise, the Hamiltonian is studied in a general way, and particularly for the hydrogen molecule. We learned the main knowledge relating with Quantum Chemical and after that we focus in the study of some diatomic molecules no studied in the literature until now. Then, a phenomenological study was carried out for the BrCl molecule.Item Aplicación de la espectroscopia de infrarrojo cercano (NIRS) en productos cárnicos(Universidad Santiago de Cali, 2024) Rosero Martínez, José Miguel; Castro Narváez, Sandra Patricia (Director)An approximation is made to near infrared spectroscopy (NIRS) as a tool for evaluating the quality and authenticity of meat products. Given the growing demand for organic meat products and the need to guarantee their integrity, NIRS stands out as an effective alternative to traditional methods. The methodology employed included literature review, data analysis and method comparison, highlighting the importance of developing more robust calibration and standardization techniques. Quality parameters that NIRS can assess, such as moisture, fat, protein, color and pH, were identified, demonstrating its ability to provide rapid and non-destructive results. Comparison between NIRS and traditional techniques such as proximate analysis revealed that NIRS offers significant advantages in terms of speed and reduced need for sample preparation. However, limitations have been identified, including the need for specific calibrations for each type of meat and the dependence on the quality of the equipment used. Recommendations include advancing the development of calibration techniques and exploring the integration of NIRS technology in real-time computing environments.Item Aplicación de la espectroscopia en el infrarrojo cercano (NIRS), en el análisis de aceites esenciales para aplicación industrial (cosmética y farmacéutica): Revisión sistemática(Universidad Santiago de Cali, 2024) Vasquez Obando, Sergio; Orduña Ortega, Julieth (Directora); Vargas, Yaneth (Directora)This review presents the application of Near Infrared Spectroscopy (NIR) in the analysis of essential oils, specifically in the cosmetic, pharmaceutical and phytotherapeutic industries. This is a vibrational technique that uses light in the range of 780 to 2500 nm, allowing the qualitative and quantitative evaluation of biological samples. Among the most notable advantages are the minimal sample preparation and the ability to perform rapid and noninvasive analysis, however, the low sensitivity and complexity in the interpretation of spectra is a major disadvantage. The article highlights the use of NIR in quality control and in determining the chemical composition of essential oils, which are obtained by various extraction methods. The NIR technique is effective in identifying the purity and taxonomy of essential oils and in quantifying specific compounds such as terpenes. The present review also mentions the growing interest in essential oils due to their antioxidant and antimicrobial properties, and their use in natural and safe products compared to synthetic antioxidants. In the pharmaceutical industry, NIR could be used in the analysis of compounds in the pharmaceutical industry, while in the cosmetic industry, it could verify lipid oxidation and emulsion quality. NIR spectroscopy is a great tool in the analysis of essential oils, as it offers an efficient and accurate method to ensure the quality and safety of products in the cosmetic and pharmaceutical industries.Item Aplicación de la espectroscopia infrarroja cercana (NIRS) en la calidad de la caña de azúcar durante la cosecha y postcosecha: Una revisión(Universidad Santiago de Cali, 2024) Bravo España, Gefersoon; Orduña Ortega, Julieth (Directora)Near infrared spectroscopy (NIRS) has established itself as a crucial technique in the sugarcane industry, in the evaluation of quality parameters at different stages of the raw material to product conversion process. This article aims to review and compare the different recent research on the application of NIRS in determining crucial parameters in sugarcane quality at different stages of the process from identification in the cane stem to cane juice, such as fiber, Pol, total soluble solids, brix, the different linear regression techniques, the equipment used throughout this review. The most widely used NIRS analysis methodology is reflectance and transmittance since it provides sufficiently robust predictive models for the prediction of the factors already mentioned. The NIRS technique offers rapid and non-destructive evaluations, with great potential for the optimization of quality parameters in cane growth.Item Aplicación del diseño de mezclas en la formulación de sidra de manzana (Malus domestica)(Universidad Santiago de Cali, 2020) Ramírez Naranjo, Nathalia; Sinisterra Amú, Diana; Ramirez Navas, Juan Sebastián (Director)Cider is a drink with very marked characteristics with respect to other spirits; It has abundant carbon dioxide, but produces less foam than a regular beer, acquires shades of yellow in transparent and bright appearance. (Drilleau, 2005). Cider. 2. The objective of this research was to evaluate the ratio of cider mixtures from three varieties of apple (Malus Domestica): Gala, Golden and Green. This mixing design consisted of applying a planning and analysis methodology which could ensure that we obtain the knowledge and solutions. The adoption of this methodology aims to assess the influence of each component of the formulation on the selected response varieties. For this purpose, different physicochemical tests were performed on each mixture obtained: (pH, Density, Volatile Acidity, alcoholic Strength and Sugar Percentage) and from which the expected results were obtained with an average of pH between 3.6 - 3.8; Density between 0.99-1.02 g/mL; Volatile Acidity between 0.04 -0.09 g/L; Alcohol content between 0.73 - 2.4 %V; Microbiological: (Count of aerobic bacteria and mesophylls, mold count, yeast count and total coliforms) whose result of each test was <10 UCF/mL and Sensory Analysis in which preference was found for the sample called B, corresponding to the mixture 0,1/2,1/2 being this the mixture between green apple and gallium apple. The results obtained in each test were expected indicating that the drink does meet the requirements established by the Colombian technical standard NTC 222 and NTC 708, concerning alcoholic beverages and their general definitions, alcoholic beverages (Fruit wines) respectively.Item Aplicaciones de NIRS en muestras de forraje para el análisis de los principales parámetros de calidad nutricional: Revisión sistemática(Universidad Santiago de Cali, 2024) Jaramillo Zapata, Sergio Alejandro; Orduña Ortega, Julieth (Directora)Near-infrared spectroscopy (NIRS) has become established over the past decades as a rapid and non-destructive analytical technique for evaluating the chemical composition of forages. This method is based on the absorption of light in the near-infrared region of the electromagnetic spectrum and allows for the determination of various critical nutritional parameters in forage used for ruminant feed. Assessing these parameters is crucial for improving the quality of forage intended for animal feed, which directly impacts the productivity and health of ruminants. Tropical grasses, frequently used as forage, exhibit considerable variability in their nutritional quality due to environmental factors. In this context, the application of NIRS offers an invaluable tool for the rapid and accurate determination of key components, such as crude protein, fiber, and minerals, among others. This review focuses on the bibliographic search of recent studies on the applications of NIRS in forage samples, with a special emphasis on tropical grasses. The main nutritional quality parameters of forage are discussed, the NIRS technique is described, sample preparation is addressed, and the methodologies applied to obtain results in various studies are reviewed.Item Aprovechamiento de alcohol fusel en la obtención de productos de valor agregado utilizando perovskitas como catalizadores(Universidad Santiago de Cali, 2024) Valencia Castro, Jessica Andrea; Orduña Ortega, Julieth (Directora); Mora Vargas, Jorge Andrés (Codirector)At present, the quest for renewable carbon sources to generate energy and high-value products has seen a significant rise, particularly those enabling the extraction of chemical components traditionally derived from fossil fuels. Industrial processing of sugarcane yields various renewable materials, including fusel alcohol, offering the potential for conversion into valuable compounds. The catalytic conversion of fusel alcohol (mixture of different alcohols with C3 to C5) using the Guerbet reaction has not yet been widely explored, however, some of its components have already been used as starting material for this reaction using different catalysts. Thus, this work was aimed at the conversion of fusel alcohol by the Guerbet reaction using perovskite-type oxides of La (III) as cation A and Zn (II) or Ni (II) as cation B. The oxides were obtained by the calcination of their precursors synthesized by the coprecipitation method and were well characterized by infrared spectroscopy (IR), X-ray diffraction (DRX), and thermogravimetric analysis (TGA). The TGA curves showed the complete decomposition of the precursors at 900 °C in 4 hours. XRD patterns confirm the formation of the perovskite phase. In addition, IR spectra of the synthesized materials show vibrations indicating the presence of Ni-O and Zn-O bonds. In the catalytic conversion of fusel alcohol, different groups of compounds were obtained, such as alcohols, esters, ethers, and ketones.Item Aprovechamiento de los lodos de salmuera de una planta cloro-soda para la producción de carbonato de sodio(Universidad Santiago de Cali, 2018) Luna Gómez, José Luis; Ayala Cruz, Martha Isabel; Franco, Jaime Martín (Director)A methodology was carried out to obtain sodium carbonate from the brine sludge, previously characterized by ICP-OES plasma spectroscopy. The treatment consisted of adding hydrochloric acid to the sludge to generate carbon dioxide which was absorbed in sodium hydroxide solution at different concentrations to produce sodium carbonate, with a maximum yield of 62,2%.Item Aprovechamiento del alcohol fusel utilizando la reacción de Guerbet catalizada por óxidos metálicos mixtos modificados con Zn2+/Co2+ y Zn2+/Fe2+(Universidad Santiago de Cali, 2024) López Gómez, Angie Lorena; Orduña Ortega, Julieth (Directora); Mora Vargas, Jorge Andrés (Codirector)The search for methods for synthesizing value-added chemicals using renewable raw materials is constantly increasing, so the use of products and by-products derived from the industrial processing of sugar cane is of particular interest, such as fusel oil, which has been little studied as a substrate in the Guerbet reaction, which allows the synthesis of alcohols from longer chains and other products through parallel reactions. In this work, the catalytic conversion of fusel alcohol with mixed metal oxides (MMOs) derived from hydrotalcites (HDLs) modified with Zn2+/Fe2+ and Zn2+/Co2+.Zn2+/Fe2+ and Zn2+/Co2+ . The HDLs were synthesized by the coprecipitation method and through a subsequent heat treatment their respective OMMs were obtained. The materials obtained were characterized by infrared (IR) and Raman spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (DRX) and scanning electron microscopy (SEM), where their correct synthesis was confirmed. The catalytic conversion of the fusel alcohol was performed in a Bach-type reactor. Different physicochemical parameters were studied in the reaction and their products were identified by gas chromatography coupled to mass spectrometry detector. It was mainly evidenced the formation of families of alcohols and esters, followed by aldehydes, ketones and olefins, which was probably influenced mainly by the degree of acidity of MMOs according to the literature.Item Avances en las aplicaciones de espectroscopía de infrarrojo cercano (NIRS) en el análisis de los parámetros de calidad de la cerveza: Revisión sistemática(Universidad Santiago de Cali, 2024) Posada Cabrera, Javier Mauricio; Illicachi Romero, Luis Alberto (Director)In the review of beer quality management, the complexity and resources required to assess its components, such as alcohol, phenols, pH, sugars, amino acids, gases, colour, and turbidity, are addressed. Integrating physicochemical, microbiological, sensory, and spectroscopic methods is effective and efficient. Among the spectroscopic techniques, near-infrared spectroscopy (NIRS) stands out for its ability to measure multiple components quickly and non-destructively. Studies have demonstrated its effectiveness in precisely determining alcohol and other fermented compounds, reducing the reliance on slower and more expensive traditional methods. NIRS is used at different stages of the brewing process and allows for real-time monitoring that facilitates production adjustments. Experiments have validated its applicability in evaluating specific components in complex fermentations. Furthermore, the combination of NIRS with artificial intelligence and machine learning models has enhanced its precision, enabling early fault detection and optimization of the fermentation process.Item Avances en materiales electrocrómicos: Perspectiva industrial en Colombia(Universidad Santiago de Cali, 2021) Hurtado Palacios, Luis Felipe; Castro Narváez, Sandra Patricia (Directora)Item Calibración en harina de arroz blanco para la determinación de las variables de SB y BD del perfil de viscosidad por la técnica espectroscopía de reflectancia en el infrarrojo cercano (NIRS)(Universidad Santiago de Cali, 2023) Giraldo Ossa, Erika Fernanda; Orduña Ortega, Julieth (Directora); Loaiza de la Pava, Jhoana Katerine (Codirectora)Currently, the importance has increased for the genetic improvement program of the Latin American Irrigated Rice Fund (FLAR) to evaluate the quality of rice through quick, economical, environmentally friendly tools that require a minimum of preparation for your analysis. Given the above, the possibility of using the NIRS near-infrared spectroscopy technique (400-250nm) was studied through the development of a calibration equation to measure the Breakdown (BD) and Setback (SB) variables, which currently are evaluated in the Rapid Visco Analyzer RVA equipment (by its name in English), these viscosity variables of rice starch allow us to associate the cooking quality of the grain. The implementation of this technique seeks to facilitate the analysis of early generation rice lines, since currently, due to the capabilities of the RVA, it is only possible to evaluate advanced lines. The calibration was carried out on a set of 196 samples with a mathematical treatment “2,16,32,1”, an MPLS partial least squares regression model and SNV and Detrend smoothing, where the following statistical data of the variables were obtained. viscosity of BD and SB which were RSQ calibration (0.864 and 0.853), SEC (129.580 and 234.552), 1-VR (0.786 and 0.761), SECV (350.939 and 635.427) and RPD (2.168 and 2.049) respectively. Subsequently, the developed equation was verified through internal and external validation, obtaining the following internal RSQ statistics (0.822 and 0.808) and a SEP (151.909 and 309.770), RSQ external (0.791 and 0.531) and a SEP (210.444 and 944.374) respectively for the BD and SB variables. The calibration equation presents a good prediction for routine evaluation in early generation samples for the BD variable.Item Calificación de un dispositivo de inmersión para así realizar recubrimientos de TiO2/Hidroxiapatita sobre superficies metálicas(Universidad Santiago de Cali, 2019) Martínez Bellaiza, Daniela; Morales Morales, Jimmy Alexander; Castillo Ayala, Jorge EnriqueEl método de inmersión o “Dip-Coating” es utilizado para la obtención de películas delgadas sobre diferentes superficies y con un amplio rango de aplicación; este consiste en la inmersión y posterior extracción de un sustrato dentro de una solución precursora para la formación de la película. En este trabajo se realizó la calificación de un dispositivo de inmersión de bajo costo elaborado en la Universidad Santiago de Cali y se ejecutaron recubrimientos sobre sustratos de acero inoxidable con TiO2/Hidroxiapatita por la técnica de química húmeda. Para la calificación se evaluaron parámetros de velocidad y tiempo de inmersión, abordando la calificación de instalación, desempeño y diseño (IQ, PQ y QD respectivamente); la síntesis de Hidroxiapatita se realizó por precipitación controlada y se analizaron las muestras secas por IR/ATR y TGA-DSC obteniendo unos picos característicos del compuesto y un buen comportamiento térmico, además se analizaron los revestimientos realizados utilizando técnicas espectroscópicas obteniendo los depósitos esperados en los sustratos y obteniendo una relación de Ca/P de 1,57.Item Capacidad antioxidante de la semilla de aguacate (Persea Americana Mill) variedad Hass en distintos grados de germinación(Universidad Santiago de Cali, 2020) Rodríguez Sánchez, Yuly; Ramírez Navas, Juan Sebastián (Director)The avocado seed has in its chemical composition active phytocomposites; but the food industry has been limited only to the use of pulp, discarding the avocado seed. Increasing volumes of this agroindustrial remnant are expected to be generated inevitably; as a result of the growing interest in products derived from the fruit. In this study, the total phenolic content and antioxidant activity in 4 stages of avocado germination were analyzed using spectrophotometric reference methods. The total phenolic content was determined by an internal reference material of gallic acid. The antioxidant activity is referred to as the stable free radical 1,1-diphenyl-2-picrilhydrazil. The results obtained show that the antioxidant capacity increases in each stage of germination.Item Características y beneficios de los métodos de extracción de la Capsaicina en los chiles(Universidad Santiago de Cali, 2022) Ramírez Cortés, María Mercedes; Ramírez Navas, Juan Sebastián (Director)Capsaicin is the cause of the spicy sensation in peppers and likewise it can be a topical analgesic. Capsaicin is a compound made up of a phenol, an ether, and amides. It is a substance of alkaloid nature. As a technique, the bibliographic review is used and it is proposed to analyze the characteristics and benefits of the methods of its extraction in the chilies. Research studies will be extracted from academic databases such as: ACS, SciELO, Elsevier, Science Direct, Redylac, EV and USDA. At the methodological level, a descriptive study with a mixed approach is used: qualitative and quantitative; the results will allow the reader to identify the findings that indicate the most efficient and viable method for the extraction of capsaicin in chilies.Item Caracterización físico-química y funcional del almidón extraído de la papa china (Colocasia esculenta) cultivada en el Pacífico Colombiano(Universidad Santiago de Cali, 2020) Hurtado Herrera, Janer Guillermo; Castillo Ayala, Jorge Enrique (Director)The evaluation of the physicochemical and functional properties of the starch extracted from the Chinese potato tubers (Colocasia esculenta) from the municipality of Timbiquí and López de micay – Cauca was carried out. The granules had particle size around (3.5-7.8 μm in diameter for sample 1 and 3.5-7.0 μm in diameter for sample 2); a high content of % amylose (67.6 and 70.7 respectively for M1 and M2) was found compared to other botanical sources, through the colorimetric method recommended by ISO 6647. The gelatinization temperatures were (78, 6 and 81.9 ° C, respectively) by heating a solution of the starch until a stable paste formed for a few seconds. The samples showed low water solubility (0.13 M1 and 0.23 M2 g / 100 mL) and a high water retention capacity (280.3 and 391.7% at 60 ° C) compared to 226% of the cassava and 162.8% for sago: which makes it a good quality starch. The gel pastes when subjected to a % processing of light at 650 nm in a Thermo Evo 201 UV spectrophotometer was (3.4 and 4.1%) respectively. Comparing these characteristics found in this tuber with other sources of starch commonly used in the industry, it is concluded that it can be used as a promising alternative in the food industry; In addition to having a high amylose content, it is a resistant starch, providing physiological health benefits.Item Caracterización fisicoquímica de tres aceites de cocina usados para freír diferentes alimentos y los respectivos biodiesel obtenidos por transesterificación en la ciudad Santiago de Cali, Colombia(Universidad Santiago de Cali, 2024) Guerra Cuaran, Lina Alexandra; Bonilla Ramírez, Luis Fernando; Tusso Pinzón, Ricardo Andrés (Director); Zambrano Salgado, Yesid Fabián (Director)The increase in global energy demand and the environmental concerns related to the use of fossil fuels, creates the need to find more sustainable alternatives, highlighting the relevance of biofuels to reduce dependence on oil. This study focuses on obtaining three types of biodiesel from Used Cooking Oils (UCO), from the frying of empanadas, fritters, breaded chicken and a new palm oil biodiesel used as a reference. Physicochemical tests were carried out to characterize the oils and biodiesel obtained to evaluate their potential as biofuel. Their yield was determined and 93.1% fritters, 87.5% empanadas and 90.6% breaded chicken were obtained. Based on the results of the characterization and their yield, it was determined that the biodiesel from the breaded chicken ACU has the greatest potential as biofuel and the biodiesel from the breaded chicken ACU proved to be the least suitable for such use.Item Caracterización química y evaluación de un esquema tecnológico para la obtención de compuestos bioactivos de la cáscara de banano en dos estados de maduración(Universidad Santiago de Cali, 2024) Rodallega Rodallega, Esperanza; Álvarez Álvarez, Derly Natalia; Suarez Osorio, Liseth (Directora); Tusso Pinzón, Ricardo Andrés (Director)Bananas are a high-yielding crop that generates a wide variety of by-products, most notably the peels, which, depending on their bromatological characteristics, can have a variety of industrial and food applications. Likewise, phenolic compounds and flavonoids, which are common biological substances in nature, are used to treat cardiovascular problems and other pathologies associated with radical oxidation. In this research, the chemical characterization and evaluation of a technological scheme for obtaining these compounds in banana peel was carried out. This was done first by determining the percentage yield, taking into account the ripening stage, temperature, extraction time and solvent concentration. After this, a phytochemical march of the extract was developed, followed by the quantification of phenols and flavonoids by ultraviolet visible spectroscopy, the determination of the antioxidant capacity by the DPPH method, the identification of compounds by infrared spectroscopy and the evaluation of a technological scheme for obtaining phenolic compounds by means of Aspen Plus. As results, it was obtained that the most effective extraction was with 50% industrial ethanol at 50 ºC and 30 minutes of extraction, for the mature peel a percentage yield of 37% was obtained and in the green peel it was 9.78%, also, the content of total phenols was 59,590 EAG/L in the mature peel and 49,291 EAG/L in the green peel, with concentrations of flavonoids of 296 ppm and 40 ppm, respectively. On the other hand, the functional groups identified in the infrared spectrum are related to flavonoids of the flavonol type, which is estimated to be a galactocatechin, requiring 2.8 ppm of extract to inhibit 50% of the free radicals of DPPH. In addition, the aspen pluss simulation shows that the extraction of the compounds is not economically feasible.Item Caracterización química y térmica de fibras de bagazo de caña de azúcar funcionalizadas con anhídrido maleico mediante radiación de microondas(Universidad Santiago de Cali, 2022) Leal Agudelo, Francisco Javier; Caicedo Cano, Carolina (Directora); Gálvez Narváez, Jaime Alberto (Director)This work was carried out with the objective of functionalizing sugarcane bagasse with maleic anhydride to improve its compatibility with polymeric matrices, transforming its polar and hygroscopic nature. A Soxhlet wash was first performed on the cane bagasse fibers; After the fiber was washed, mixtures with maleic anhydride were prepared in the proportions 1:0.3, 1:0.5 and 1:1, where only the amount of maleic anhydride was changed in the reactions under microwave radiation. The functionalized fibers were characterized by infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and determination of the degree of acidity. The spectrum (FTIR) showed characteristic bands of the C-OH and C=O groups that indicated the formation of intermolecular interactions (hydrogen bonds), the formation of esters and carboxylic acids. Thermogravimetric analysis (TGA) showed a decrease in the thermal stability of the fibers, indicating restriction in intermolecular interactions and a decrease in the melting point compared to the unfunctionalized fiber. The determination of the degree of acidity in the functionalized fibers showed the formation of carboxylic acids. These results contributed to fulfill the objective of functionalizing lignocellulosic fibers under microwave radiation, confirming the formation of carboxylic acid molecules and esterifications, although no improvements in thermal properties were evidenced.