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The IX symposium of applied chemistry and the first international conference of Nanochemistry, Nanophysics and Nanomedicine were held at the Metropolitan Cultural Convention Center in Armenia, Colombia between august 21-23 (2019). Both were organized by Universidad del Quindio in collaboration with the Colombian Society of Chemical Sciences (SCCQ) and the Colombian Society of Engineering Physics (SCIF). The interdisciplinary meeting aimed to generate collaborations and connect different professionals framed in the chemical sciences intersected with physics, material science, agricultural sciences, maths, biology, medicine, engineering among others. 80 students and professionals registered to 5 pre-congress courses and 450 participants from 6 countries attended 3 days of multidisciplinary discussions with 10 plenary talks, 90 oral presentations and 200 posters.

In the 9^th version of the symposium, researchers focused of Chemistry as a discipline that studies matter, what it consists of (atoms, molecules, ions), what its properties are, and how it changes or it could be transformed that conducted at the nanoscale intersects with nanotechnology. The design of devices, sensors, processes and products can be designed, functionalized and implemented from building blocks either atoms or nanomaterials. In the conference projects, ideas and results were discussed around green chemical and physical synthesis (Microwave assisted synthesis) of Nanoparticles, how nanomaterial´s ligand coatings could be modified for improved detection, modification of Surface charge distributions, to improve Nanomaterials (NMs) characteristics such as stability, and selectivity; the studies of metal-ligand cooperation phenomena that can occur in organometallic complexes and impact the election of ligands for selective and efficient catalysis. In addition to the design of shells to form interface layers that combined all the possibilities from inorganic to organic, to the embedding of NMs into polymer networks and their integration with large of Networks and Nanostructures for the design of functional materials. Scientist highlighted experimental evidence for the different materials Nms can be made of and sizes and shapes there could be produced at and the need to understand the potential hazards and risk in all the activities that involved the creation, use and disposing of Nms and residues. A debate kept the questions of the regional production of these nanomaterials to supply the needs of the current industry in Colombia and the human protection for the unknown hazards. Researchers also include discussion around the Nms fusion with living matter for applications on cancer detection and other Terminal illnesses.

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All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

In this work, we analyze the charge localization in DNA molecules using an effective tight-binding approach that includes the backbone onsite energies. The localization length and participation number are examined as a function of energy dependence. We see that for specific energy ranges, the electronic states spread out into all sites, while in other energy ranges, the probability density is highly concentrated on either the backbone sites or the nucleotide like sites.

In this study, the electrochemical behavior of diclofenac (DCF), a widely used NSAID drug, was undertaken at a modified glassy carbon electrode (GCE). A low-cost, sensitive, stable, and selective electrochemical sensor is proposed for the determination of this analyte by using differential pulse voltammetry in 0.10 M phosphate buffer solution, pH 8.00. At the Surface of GCE, EDOT (3,4-Ethylenedioxythiophene) was electropolymerized by chronocoulometry, the charge injected was carefully controlled. The polymerization parameters were 20.0 mM EDOT, H₂SO₄ pH 1.50, step potential from 0.0 V to 1.1 V vs Ag/AgCl/KCl(sat), for 60 ms. The modified GCE displayed a significant enhancement of the anodic peak current compared to the bare electrode, measured by DPV. A calibration graph of the modified electrode exhibited an increase of the peak current about 63% with respect to the bare. The electropolymerized sensor was applied to DCF quantitation in pharmaceutical preparations with a relative standard deviation of 0.40%. It was also used in urine analysis. The limit of detection of this sensor was 9.06 nM compared to 1.37 μM for the bare electrode.

Silver nanoparticles (AgNps) are known for their antimicrobial activity and other physicochemical properties that can be applied in several fields. Most of their synthesis methods include chemical reduction and the use of stabilizing agents such as starch. In recent years, several green methods have been developed such as using carbohydrates as reducing agents. On the other hand, starch is a semi crystalline structure formed by mixtures of the linear glucan, amylose and the branched glucan amylopectin. In this work we studied the effect of the semi crystalline structure on the physicochemical properties (particle size and surface plasmon resonance). Three types of starch were selected (corn, potato and banana) representing the three types of semi crystalline structures of the starch granule (A, B and C). Results showed that banana starch allowed larger particle sizes and broader size distribution, while there was not significant difference between nanoparticles stabilized with A and B type starches.

Chitosan is a biopolymer extracted from the shell of crustaceans. It is currently possible that this be modified to improve its bacterial properties. In this context, in the present work new materials were synthesized as electro-spun films, where the best conditions were establish that led to biocidal activity against to Staphylococcus aureus ATCC 6538. The addition of PVA to chitosan improves electrospun conditions since the chitosan alone cannot stabilize the voltage. The best interaction with water was resolved at 16 % PVA, increasing the hydrophobic capacity of the film. The ion metallic interacts with chitosan matrix through acetyl group, and the alcohol and ammine group do not participate in electronic interaction. Finally, this work shows that the metal ion increases the biocidal properties of chitosan as a thin film.

Ecological awareness as an ethical obligation is conceived. A product, a prototype or a process must culminate efficiently when incorporated into a production chain; its life cycle will depend, therefore; of its use, reuse and recycling. This project presents an industrial vision in conjunction with agriculture. For this, a general problem of interaction between products (agribusiness chain of the banana plant and reuse of conventional polymeric waste) that work within the same context has been addressed. Colombia has climatic conditions that weigh this country as one of the major producers in the banana zone. Today Colombia is recognized for its quality and for its exports, which reach a figure of 1,578,112 Tons of Banana as of December 31, 2017, and amount to 86.99 million boxes of approximately 18.14 Kg. Once the fruit is harvested, it is packed and exported; at the end of this process, the leaves and stems of the plant become waste. This residue called pseudostem has a mass percentage of about 51% with respect to the total plant. In economic terms, 1,667,000 metric tons per year correspond to this waste, an important economic factor in regions where bananas are high, as is the case in Risaralda. In response to this situation, we find that the banana pseudostem is a low-cost fiber, which increases its mechanical strength when mixed with medium density polymers. These characteristics allow mixing cellulosic residues with residual polymers such as polypropylene, the incorporation of load and reinforcement elements in thermoplastics has been a common practice in the plastics industry whose purpose is the reduction of production costs of molded products, and the improvement of thermo-mechanical properties of polymers. In this context, new materials are proposed based on the mixture of polypropylene and fiber with percentages of 10%, 20% and 30%. For these materials, the process variables were evaluated based on obtaining the pellets by extrusion and finally the samples to which the mechanical properties were estimated. On the other hand, the 3D design of the potential application in roof tiles for construction is reported and it is concluded that at 20 % fiber the degradation. There is a good consistency of pellets, but there is a drastic detriment of traction.

The research reports the synthesis of α- MnO₂ and CuO nanoparticles obtained from laser ablation method. Based on the properties as semiconductors, the oxides as bactericity systems for Escherichia coli ATCC 11229 and Staphylococcus aureus ATCC 6538 have been tested. The influence on plasmon was evaluated, in relationship to the energy, time and wavelength of the laser used. The dispersion of nanoparticles for manganese oxide were in function of the energy, and its frequency oscillation is greater than copper oxide, due to the effects of charge transfer. The effect of a chiral organic compound was estimated in situ, generating stability and reproducible biocidal properties. Finally, it is important to mention that the biological activity was mediated by the semiconductor capacity. Control experiments will be necessary for to continue for the understanding of the mechanism.

The scientific community is focused on the development and use of new nanomaterials to create novel devices and systems that can be useful to solve problems or provide services. Among all nanomaterials, semiconductors allow improving optical, electrical, and catalytic properties of several surfaces, including the corrosion resistance of the materials; corrosion causes several problems and economic losses in the food, pharmaceutical, and hospital industries because the materials selected must be durable, economic, and as innocuous as possible. Zinc oxide (ZnO) is one of the most interesting materials, is a photo-chemically active n-type semiconductor and has particular defects into intrinsic lattices, such as Zn and O vacancies. Herein, we use electrophoretic deposition (EPD) for the synthesis of nanostructured films composed of ZnO nanoparticles (ZnONPs) as a protective coating on low-alloy carbon steel. The electrochemical stability of the coated steel was evaluated and compared with the response of the bare steel. This work used NPs formed in homogeneous media and in reverse micelles (RMs) formed in our previous published report. The coatings were synthesized on the surface of SAE 1020 carbon steel electrodes with 12 mm diameter. As results, two different colloidal systems were formed, by RMs we synthesized high mono-dispersed and spherical 3-5 nm ZnONPs, and by homogeneous media anisotropic 20-100 nm ZnONPs, both systems with excellent fluorescence emission at different excitation wavelengths. The electrochemical evaluation confirms the stability of the coatings obtained, improving the corrosion resistance of the low-alloy carbon steel. We found that the coating obtained with the smallest particles shows better protective properties; the difference between both coatings could be related to the force balance during the electrophoretic deposition, where the friction force, that is against the electrophoretic movement, is proportional to the particle size, reducing the amount of deposited material.

The formation of thin films based on TiO₂ plays a fundamental role in research involving solar energy (solar cell and solar thermal collectors) and from the part environmental (photocatalysis-artificial photosynthesis as a source of clean energy). In this sense, our work has focused on the experimental details directed towards the method of obtaining, for which as a precursor salt Titanium Oxyacetylacetonate (IV) (Sigma Aldrich with 90 % purity) it has been used dissolved in methyl alcohol (Fisher Chemical with 99.8% purity) in 0.05 M molar concentration. The effect on deposited films was studied by varying airflow (2 L/min - 6 L/min) and substrate temperature (150 °C - 450 °C). For the Optical and structural characterization was used UV-VIS spectroscopy and X-ray diffraction techniques. From the analysis of the results was determined the energy band gap with values around 3.5 eV for all films. The Anatase phase with tetragonal structure was find it, refined using the Rietveld method that determined network parameters of a = 3.807617 Å, b = 3.807617 Å, c = 9.547797 Å, the thickness of the films ranged in a range between 70 nm - 150 nm whose values depended on the deposit conditions. The previous evidence allows concluding that this material can be used as an anti-reflective layer to be implemented in solar collectors.

This study describes the determination of Polynuclear aromatic hydrocarbons in water using a new modification for the commercial SPME-HPLC interface which incorporates a dynamic SPME-HPLC extraction and vibration in the desorption chamber during the extraction and desorption steps. Extraction and desorption parameters were investigated using fourteen PAHs of different volatilities (naphthalene, acenaphthalene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene) as test compounds and fluorimetric detection. Regression coefficients close to 0.99 with RSD < 8.1% and detection limits in the range 0.004-0.59 µg/L were found. A method was applied to determine the above PAHs in water samples. The results were compared with the 550.1 EPA method at the 0.05 significance level.

In this work, we calculated the band structure for the monolayer black phosphorus (phosphorene) from the slater-Koster tight-binding method, where the effect of s-p mixing is considered. Using the new parameters, we studied the electronic properties of phosphorene. The electronic properties were calculated using the recursive Green's Function method. From the resistance calculation, we showed that electrons in the ZZ directions had an effective mass ten times larger than those in the AC direction, which agrees with experimental results. We investigated the effect of disorder on the anisotropy of the effective mass and we showed that the intrinsic anisotropy is robust to the presence of disorder.

We have theoretically investigated the structural stability of the predicted polar phase on the layered Tungsten-based oxide BaWO₄ at high pressure. Although the energy vs. volume curves report a non-centrosymetric Cmc2₁ phase in BaWO₄ oxide under pressure, we found that such a phase is dynamically unstable when the phonon-dispersions are considered. Additionally, we have observed that the polar eigendisplacements, related to WO₆ octahedral rotations, are destroyed once the internal coordinates are allowed to fully relax. Thus, the symmetry of the crystalline material is transformed into a Cmcm phase, where we found a dynamically stable layered structure.

Here, we present the study of the ferroelectricity in the ABF₄ materials with A = (Sr, Ba) and B = (Mg, Zn). This theoretical study was performed based-on first-principles calculations within the density-functional theory, DFT, formalism. We found that the geometric ferroelectricity in ABF₄ layered compounds can be tuned by changing the A-site with Sr and Ba cations and B-sites with Mg and Zn atoms. Additionally, we studied the stability of the phases as a function of the A and B cations' occupation preference. We observed a layer-by-layer disposition, as a ground state, when the A-site has different compositions of Sr/Ba.

In the present work we report the synthesis of mixed ferrites doped with Co²⁺, Cu²⁺ and Ba²⁺ cations, using citrate sol–gel combustion route in air atmosphere, at 950 °C for 3 hours, produced substituted M-type barium ferrites powders particles with crystallite sizes varying between 145 and 155 nm. The percentages of yield obtained were on average 42%. The synthesized ferrites were characterized by techniques such as powder X-ray diffraction, evidencing the formation of M-type barium hexaferrite and copper and cobalt substituted M-type barium ferrite with hematite in smaller proportion. The possible growth of M-type barium ferrite with copper and cobalt may be due to a larger size of the cobalt atom with respect to copper and that a higher proportion of cobalt salt was used in the synthesis route. Increase in the metal ion substituted content leads to a decrease in the lattice strain and may be responsible for an increase in the crystallite size because greater tensile strain leads to elongation of the particles. The particle size of the synthesized ferrites differs significantly when they are doped, with Ferrite doped with copper having the smallest particle size compared to Ferrite doped with cobalt. We also performed spectroscopic analyses, RAMAN that showed, the substitution of cooper or cobalt in the M-type barium ferrite powders particle leads to a minor intensity of resonance band when compared with the parent compound and the differences between Fe³⁺, Cu2⁺ and Co²⁺ ions in a tetrahedral coordination is their ionic radii. The increase in the ionic radii causes a local distortion and vibrational bands of distorted polyhedra in substituted M-type barium ferrites. The chemical composition of this sample was determined as Ba_1.0Fe_11.83O_19.22, Ba_1.0Co_1.02Fe_11.01O_18.35 and Ba_1.02Cu_0.56Fe_11.35O_18.26 using an AAS device. Both are very close to the theoretical formula. The influence of the synthesized ferrite samples was explored in the ozonation of a dye of unknown chemical structure. The effect was evidenced by visible ultraviolet spectroscopy technique. The results obtained show that the ink could be decolorized by applying oxidation by ozonation, however, when substituted M-type barium ferrite is added, the discoloration increases when this is doped with copper and cobalt, being higher using this last ferrite. The degradation process by ozonation presented in this work, carried out in the presence of copper and cobalt substituted M-type barium ferrites, would constitute an example of technology for the environment.

Fe_0.70Al_0.30 alloy is a bcc and ferromagnetic phase, being the Al atoms magnetic dilutor. In this work, we study the effect of the Nb on the structural and hyperfine behavior of the Fe_0.70Al_0.30 alloy when atoms of Nb substitute atoms of Fe or Al. The nanostructured system of (Fe_0.70Al_0.30)_1-xNb_x (x = 0, 0.05, 0.10, 0.20, at. %) was obtained by alloying Fe, Al and Nb powders in a planetary ball mill during 12 h, 24 h and 36 h, and a ball mass to powder mass relation of 10:1. The magnetic and hyperfine properties of the samples were studied by X-ray diffraction (XRD) and Mössbauer Spectrometry (MS) at room temperature, respectively. The X-ray diffraction patterns for x=0 showed the bcc-α FeAl structure and its lattice parameter is approximately constant with milling times (∼ 2.91 Å). For x=0.05, 0.10 and 0.20 the patterns showed the coexistence of the α-FeAl, Nb(Fe,Al)₂ structural phases with an amorphous component. The Mössbauer spectra of x=0 samples were fitted using hyperfine magnetic field distributions (HMFDs), and the obtained mean hyperfine fields (MHF) were 23.4, 24.2, and 24.3 T for 12, 24, and 36 h of milling time, respectively, which correspond to the α-FeAl structure. The spectra of the samples with x=0.05 and 0.10 were fitted using a model with two components, the first one is a HMFD attributed to the bcc-FeAlNb structure and the second with two doublets attributed to the Nb(Fe,Al)₂ structure. When atomic percentage of Nb increases up to 20 at. % the ferromagnetic behavior is diluted due to substitution of Fe-atoms by Nb and Al atoms in the bcc-FeAlNb structure. The magnetic behavior becomes paramagnetic at x=0.20, the spectra were fitted with three doublets, one of them related with bcc-FeAlNb structure and the others to the Nb(Fe,Al)₂ structural phase. The alloying of Nb to the Fe_0.70Al_0.30 system destroyed the magnetism due the substitution of Fe by Nb atoms and generates an amorphization into the system.

A chemical synthesis route for facile, fast and economical production of reduced graphene oxide/zinc oxide composites (rGO/ZnO) via a microwave-assisted hydrothermal method is presented. For a particular concentration (124 mM) of zinc acetate di-hydrate (Zn(CH3COO)2.2H2O) acting as precursor of Zn, different microwave irradiation times of the order of seconds were tested in order to select the more adequate time. Furthermore, with the selected irradiation time (40 s), different concentrations (31, 62 and 124 mM) were then considered and chemical and morphological properties of the obtained composites were evaluated. For their characterizations SEM, EDS, FTIR, Raman spectroscopy and XRD were employed. Experimental results confirm that the proposed synthesis route for the fabrication of rGO/ZnO is efficient, environmentally friendly and cost-effective.

Titanium dioxide (TiO₂) is a very stable semiconductor physically and chemically, it is an abundant material and harmless to nature. Currently, TiO₂ is one of the most used photocatalysts to degrade organic molecules in both water and air during purification processes. In this work, we fabricated Nitrogen-doped TiO₂ powders by the Sol-Gel method, the Titanium tetraisopropoxide and urea were as reagents; subsequently, the materials were supported as thin films on glass using the technique of Doctor Blade. The materials were characterized by using different analytical techniques such as Raman spectroscopy, X-Ray Diffraction (XRD), and diffuse reflectance spectroscopy (DRS). The XRD results indicated that TiO₂ films presented a single crystalline phase, corresponding to the anatase. Besides, Raman spectroscopy verified the nitrogen incorporation in the crystal lattice of TiO₂ after the doping process. Furthermore, DRS results showed an improvement in optical photo-response at the visible region of the electromagnetic spectrum, the band-gap narrowing was verified from 3.25 eV for unmodified TiO₂ thin films until 2.84 eV TiO₂–N(5%) thin films. Finally, the photocatalytic activity of materials was studied during methylene blue (MB) degradation, the photocatalytic degradation results indicated the doping process enhanced photocatalytic activity under visible irradiation.

Silver nanoparticles have been obtained by colloidal synthesis using two different reducing agents: ascorbic acid and ethylene glycol. The colloids have been characterized by UV-Vis Spectroscopy, atomic absorption and transmission electron microscopy (TEM). The UV-visible spectra show the typical peak with a maximum ranging between 390-420 nm, due to the plasmon resonance of spherical silver nanoparticles. TEM micrographs show non-aggregated spherical silver nanoparticles whit diameters between 30 and 50 nm. The antibacterial effect was tested in three different bacteria cultures: Escherichia coli (gram negative), Staphylococcus epidermidis (gram positive) and dental plaque, which were grown in Mueller-Hinton agar. For comparative purposes the bactericidal effect of silver nitrate was also evaluated. Inhibition index (IIC) was calculated, obtaining satisfactory results for the three kinds of microorganism when silver nanoparticles are used.

A voltammetric method optimized for the sensitive and reliable study of the UV/H₂O₂ oxidation of glyphosate (N- (phosphonomethyl) glycine) (GPS). The cell consisted of three electrodes in a compartment, silver wire coated with silver chloride as a pseudo reference electrode, platinum electrode as working electrode and stainless steel as auxiliary electrode. GPS cyclic voltammetric analysis suggests the formation of a GPS-Pt complex on the electrode surface, with an enhanced signal in perchloric acid between 1.3 to -1.3V; sensitive to protonation of the amino group, no response observed at pH values greater than 5.00. The oxidative degradation of GPS with UV/H₂O₂ is evident at pH 3.0, it exhibits first order pseudo kinetics with a half-life of 40 ± 4min. Two degradative routes are estimated depending on the concentration of H₂O₂: at low concentrations (H₂O₂/GPS 1: 100 ratio), the formation of sarcosine and then glycine is favored; at H₂O₂/GPS 1:20 and 1:10 ratios predominate the formation of glycine.

Pulsed laser ablation in liquids (PLAL) synthesis of Nanoparticles (NPs) is a bottom-up process with the advantage of the absence of chemical reagents in the solutions. In this process, NPs shape and diameter distributions on PLAL experimental parameters. We research the hydrodynamic diameter of the ZnO Nps correlation to media, wavelength, fluence, and irradiation time. Nine solutions, five in methanol and four in ultra-pure water were processed with fluences ranged from 4 to 15 J cm⁻², target irradiation times from 8 to 15 min, and for wavelength of 532 nm and 1064 nm. We characterized the morphology and diameter distribution using Scanning Electron Microscopy (SEM) and Dynamic Light Scattering (DLS). Results showed that prolonging the irradiation time, reduces the diameter of the ZnO NPs by 41.4 % in methanol and increases it by 19.8 % in ultra-pure water. Change of medium from ultra-pure water to methanol revealed a maximum decrease of 84.2 % in NPs diameter while lowering the fluence resulted in a 62.6 % diameter reduction. The experimental results indicate that the medium and fluence were the most relevant parameters to obtain small NPs in methanol media with 80 nm diameter at 5 J cm⁻², a wavelength of 1064 nm, and 20 min irradiation time and the diameter was less dependent on wavelength. Understanding the synthesis parameters and their effect on Nps diameter dispersion is critical for the scaling-up production to meet the PLAL's promise of several grams per hour.