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Hops' (Humulus lupulus L.) phytochemicals are well known for their bioactivity. In the present study, the functional properties of hop extract rich in β-acids, as potassium-salts structures (KBA), were investigated to develop a sustainable active food packaging. Polylactic acid (PLA)-based sheets were incorporated with increasing concentrations of hop extract (0.1-5 % w/w in terms of KBA) and characterized through performance and bioactive properties. KBA-added sheets presented decreased crystallinity and affected mechanical and thermal properties, especially with higher KBA amounts. The sheets' surface hydrophobicity gradually decreased by KBA-extract addition, while the water vapor permeability was not affected. A Fickian diffuse behavior and a better fit to application in fatty foods were observed during release tests. UV-blocking and antioxidant properties were improved by KBA incorporation. Furthermore, results from antibacterial assays revealed great susceptibility of Staphylococcus aureus and Listeria monocytogenes towards sheets added with 5 % of KBA. Moreover, the atomic force microscopy (AFM) observations revealed that KBA led to strong effects on the cell membranes of both bacteria, including disruption of membrane integrity and cell death. Therefore, this study is a sign of great prospects of hop β-acids use, as KBA compound, in the production of sustainable active packaging for safe food shelf-life extension.

Semiconductors structures with high quality and low cost have been developed and applied in industry on a large scale. The knowledge of basic properties of semiconductor materials growth is important for many technological applications. Cd 1-x Mn x Te films have been used successfully in optoelectronic, solar cells and high energy detectors applications. However, despite the high potential for application of these films, fundamental growth studies on Si(1 1 1) substrate are not extensively explored. In this study, two Cd 1−x Mn x Te (CMT) films (with different Mn concentrations) were successfully prepared on Si(1 1 1) substrate employing molecular beam epitaxy. The morphology and surface roughness of the films were investigated using atomic force microscopy (AFM). X-ray diffraction was used to investigate the structural quality and to determine the Mn concentration of the samples. It shows that the films have only (1 1 1) orientation despite a lattice mismatch of almost 19%. Room temperature micro-photoluminescence (µ-PL) spectra shows a high intensity band edge emission and very low intensity defect related emission. Raman spectroscopy of the samples was carried out in order to obtain the vibrational modes. First, second and third order CdTe-like and MnTe-like longitudinal-optical (LO) phonon modes were observed. These results demonstrate the potential of these structures for room temperature applications.

The complex crystals of the family of the Tutton's salt have been investigated through the numerous experimental and theoretical studies to understand their physical properties and their potential technological applications. In spite of the more than 60 years of research, there are very few studies about the electronic properties of Tutton's salt. In our present work, we have calculated the stability, electronic properties and the first theoretical study of band structure of the three different crystals of the Tutton's salt, ammonium nickel sulfate hexahydrate ((NH4)2Ni(SO4)2·6H2O), ammonium nickel‐copper sulfate hexahydrate ((NH4)2Ni0.5Cu0.5(SO4)2·6H2O) and ammonium copper sulfate hexahydrate ((NH4)2Ni(SO4)2·6H2O) with the help of periodic ab-initio calculations based on density functional theory (DFT). In addition to this, the internal Raman and FTIR modes of the ionic fragments [Ni(H2O)6]2+, [Cu(H2O)6]2+ NH4+ and SO42− of the sample crystals were obtained by employing the ab initio and the orientation of the molecular vibrations of the ionic fragments have been presented in picturized form. Furthermore, the Raman and FTIR spectroscopy of the sample crystals were measured in the range 100–4000 cm−1 and 400–4000 cm−1 respectively, and the internal vibrational modes obtained from experimental measurement have been compared with those obtained from DFT calculations.

In this work, phosphomolybdic acid salts were synthesized exchanging their protons by the Sn(II) cations (i.e., H3-xSnx/2PMo12O40; x = 0.0, 1.0, 2.0, 3.0), and evaluated in the etherification reactions of glycerol with tert-butyl alcohol (TBA). The catalytic activity of the phosphomolybdate salts containing a variable load of Sn(II) ions was further compared to phosphotungstic and silicotungstic acid salts (i.e., H3-xSnx/2PW12O40; x = 0.0, 1.0, 2.0, 3.0 and H4-xSnx/2PW12O40; x = 0.0, 1.0, 2.0, 4.0, respectively). The integrity of the Keggin anion after the synthesis was confirmed by infrared spectroscopy analysis. Physical properties were determined through thermal analyses, powder X-Rays diffraction patterns, N2 adsorption-desorption isotherms, and scanning electron microscopy. The acidity properties were analyzed by adsorbed pyridine FT-IR spectroscopy, NH3-programmed-temperature desorption, and potentiometric titration. Among all the Sn(II) heteropoly salts tested, the Sn3PMo12O40 was the most active and selective catalyst toward glyceryl ethers. The highest activity of Sn3PMo12O40 was assigned to the greater Lewis acidity strength. Modeling, simulation, and economic analysis allowed to evaluate the viability of the process. An annual capacity of 30,000 metric tons was developed, and the process is feasible with a return on investment (ROI) of 30.7%.

Dengue virus (DENV) is an arbovirus that belongs to the Flaviviridae family. Studies reveal that peptides secreted by amphibians have many functions, such as antiviral and antimicrobial activities. As there is no antiviral drug effective against the DENV, the antiviral activity of a synthetic peptide called HS-1, derived from the secretion of the anuran Hypsiboas semilineatus, has been evaluated. The assays of neutralization in the Vero cells show a complete inhibition of infection of the serotypes 2 and 3. Furthermore, the direct action of peptides on the viral particle can be observed through atomic force microscopy. In vivo tests display 80% protection against the dengue-2 virus due to the presence of HS-1, which reveals its potential as an antiviral against the DENV.

Hydrocalumite (CaAl-LDH) was prepared by the co-precipitation method with different Ca2+/Al3+ molar ratios. Hydrocalumite at the molar ratio of 4:1 Ca2+/Al3+ (4HC) showed to be efficient in the removal of Cu2+, Ni2+ or Zn2+ from the aqueous solution. The products formed between 4HC and the Cu2+, Ni2+ or Zn2+ cations were characterized by atomic absorption, SEM, XRD and IR. The effect of several factors such as pH, dose, contact time and metal concentration were evaluated. The maximum removal capacity was 7.0 mmol g−1 for Cu2+ and Ni2+, and 6.3 mmol g−1 for Zn2+. X-ray diffraction analyses showed that the products formed were CuAl, NiAl and ZnAl LDHs. The 4HC also was applied for removal of metal cations and the oxyanions Cr(VI) or phosphate from the same solution. In solutions containing 400 mg L−1 of Cu2+, Ni2+ or Zn2+ and 200 mg L−1 of Cr(VI) or phosphate (expressed as phosphorus), and in the presence of 1 g L−1 of 4HC, 100% of the metals and 60, 57 and 52% of Cr (VI) or 93, 80 and 92% of phosphate were removed, respectively. The results showed that 4HC has great potential to be used in the treatment of effluents containing metal cations and oxyanions.

Energy-efficient Heating Ventilating and Air Conditioning (HVAC) system utilization is necessary to reduce energy consumption in buildings amid the supply difficulties of energy sources and the environmental impacts of high energy use. This study aims to investigate the utilization of a finned U-shaped heat pipe heat exchanger (HPHE) in a vertical configuration to reduce cooling and reheating energy in an HVAC system. The effectiveness of the U-shaped HPHE, coefficient of performance (COP) of the HVAC system coupled with U-shaped HPHE, and dehumidification capability are presented in this paper. The U-shaped HPHE was installed at the inlet fresh airstream ducts wrapped around the cooling coil, and tests were carried out with one-and two-row configurations arranged in eight heat pipes per row. The fresh air temperature and velocity across the evaporator section were varied at the ranges from 30 to 45 °C and 1.5 to 2.5 m/s, respectively. The results show that the two-row U-shaped HPHE significantly affects the precooling and reheating processes in the HVAC system compared with the one-row configuration. The two-row U-shaped HPHE can enhance the coefficient of performance (COP) by 39.9% over the HVAC without HPHE. The highest energy saving for precooling and reheating was 288.1 and 340.2 W, respectively, at 0.080 m3/s air volume and can reduce relative humidity by 21.6%. The investigation implies that the U-shaped heat pipe succeeded in becoming a solution to an HVAC system that requires cooling to reheat the HVAC system.

Intermittent gas lift is one of injection techniques for mature wells with low-productivity. This technique has two periods i.e. shut-in and production periods. During shut-in period the choke is closed, and the gas flows from the compressor into the gas-line. Furthermore, production period takes place when the choke is open to allow the gas flows into the tubing-casing. This process is similar to line-pack and line-draft in transient gas flow. It is known that the upstream choke pressure should be high enough to lift the oil. Hence, it is very important to control the shut-in period. In this paper, a line-pack model for an intermittent gas lift is constructed. The model is used to predict high-pressure performance at the upstream choke. Moreover, the model is compared with field data from literature. The effect of opened-closed choke to the pressure and the gas rate is analyzed. Sensitivity analysis with respect to gas-line length, gas rate, discharge pressure, and duration of shut-in are shown. The results show that the pressure at the upstream choke can be estimated as well as the duration of shut-in which are critical in increasing the pressure. This model is important for avoiding production operation failure.

Household lifestyle is increasingly influenced by income level, flexibility of work, family pattern and daily life of electric appliance usage that affect residential energy consumption. The aim of this research is to investigate the effects of household lifestyle on residential energy consumption. This research used cross-section analysis and on-site measurement methods focusing on household lifestyle using life schedule data. The results have pointed out that household lifestyles were closely related to energy consumption. Cooking activities consumed more energy compared to the other four activities due to number of electric appliances usage, included permanently used appliances and intermittently used appliances. In terms of family patterns, households with big families are expected to have, higher the energy consumption, but the average energy consumption per person is smaller due to the sharing of equipment. Household with retired or housewife and government employee generally consume more energy due to longer hours spent at home. This study also found that power consumption (operation and standby mode), number of appliances and operating hours are the three aspect that will plays an important role to decrease residential energy consumption in the future.

A series of TiO 2 /MgZnAl photocatalysts were successfully synthesized from ternary (Mg, Zn and Al) layered double hydroxides impregnated with TiO 2 nanoparticles by the co-precipitation method at variable pH with different Zn 2+ /Mg 2+ molar ratios. The composite photocatalysts were calcined at 500 °C resulting in the incorporation of oxide zinc, in the calcined MgZnAl LDH structure. Synergistic effect between ZnO and TiO 2 lead to significant enhancement of TiO 2 /MgZnAl photocatalytic activity. Composite photocatalysts were characterized by ICP-MS, N 2 adsorption-desorption, XRD, SEM, EDS, IR and UV–vis DRS. Phenol in aqueous solution (50 mg/L) was used as a model compound for evaluation of UV–vis (filter cut-off for λ > 300 nm) photocatalytic activity. The most efficient photocatalyst composite was obtained at a 5% Zn 2+ /Mg 2+ molar ratio, in the catalyst identified as TiO 2 /MgZnAl-5. This composite catalyst had high photocatalytic activity, completely destroying phenol and removing 80% of total organic carbon in solution after 360 min. The TiO 2 /MgZnAl-5 catalyst remained relatively stable, presenting a 15% decrease in phenol degradation efficiency after five consecutive photocatalytic cycles.

The magnetic adsorbent iron oxide-hydrotalcite modified with the surfactant dodecylsulfate (DS) and β-cyclodextrin (β-CD) was evaluated in the removal of phenol (PHE), p-nitrophenol (PNP) and p-cresol (PCS) from aqueous solution. The magnetic adsorbent was named Fe/HT-DS/β-CD and has the advantage of being easily removed from aqueous solution through application of a magnetic field. The adsorbent was characterized by Infrared Spectroscopy (IR), X-ray diffractometry (XRD), Raman spectroscopy, Scanning Electron Microscopy (SEM), Energy Dispersion Spectroscopy (EDS), Atomic Absorption Spectroscopy (AAS), zeta potential and elemental analysis (CHNS). The effect of pH, dosage, contact time, kinetics, temperature and adsorption thermodynamics were evaluated by phenolic compounds removal. The maximum adsorption capacity of the PHE, PNP and PCS by the adsorbent were 216.08 mg g−1, 255.63 mg g−1 and 272.48 mg g−1, respectively, at 180 min, pH 6 and 25 °C. The thermodynamic parameters indicate that the adsorption is spontaneous and endothermic. This adsorbent showed satisfactory results when applied in the treatment of pulp and paper industry effluent that naturally contains phenol, p-nitrophenol and p-cresol and fortified river water samples.

Biodegradable polymers can produce sustainable films to substitute regular food packaging as an answer to environmental concerns and food preservation. Nisin Z (NIS Z) bioactive compound can be embedded into biodegradable polymers, such as polyvinyl alcohol (PVA) and starch, to produce antimicrobial eco-friendly active films. Cellulose nanocrystals (CNC) and maleic anhydride (MA) have been added into matrix films, as reinforcement compounds, to improve polymer’s performance. For this reason, Corn Starch-PVA biodegradable film blends were produced by the incorporation of CNC, MA and NIS Z according the concentration values obtained from the Central Composite Designs. Desirability function was stablished promoting a maximization of antimicrobial effects and mechanical features and a minimization of barrier responses. Film topographies were examined using a profilometer and a scanning electron microscopic and a heterogeneous surface patterns were observed. Moreover, the active films were also evaluated by X-ray diffraction and color analysis. L. monocytogenes control efficiency by the films highlighted the potential to produce active biodegradable films as an alternative to the addition of food preservatives against this bacteria’s growth.

Producing paint using waste and soil is an efficient way of contributing to sustainable development and reducing costs in the finishing and protection of buildings. Although there are numerous studies related to paints of natural land base, there remain certain technical limitations to be overcome. Moreover, no research has been found in the literature on the use of marble waste as an active or inert pigment in the production of paint, although this waste has several pertinent properties and basic constituents. Thus, the aim of this study was to evaluate whether the use of untreated marble waste as an active pigment in building paint enables a product to be developed which meets specifications and whether the performance of soil pigment-based paints can be improved by incorporating marble waste as a mineral filler. The only preparation for using the waste and the soils as pigments was to sieve them to remove coarser impurities. The samples were formulated based on mix planning using the simplex network and consisted of: marble waste pigment (MWP), soil pigment (SP) and polyvinyl acetate resin (PVA). The amount of water varied according to the ideal viscosity range for paint application. The formulas were analyzed for hiding power (HP), abrasion resistance (AR), microbiological attack and resistance to weathering. The results showed that, for paints produced with MWP as the only pigment, the performance set out in ABNT NBR 15079:2011 was achieved above a percentage of 30% resin in solution. Furthermore, the addition of MWP to SP-based paints provided a film with higher HP and, together with the increased resin content, increased the AR of the samples. Five formulas met both HP and AR performance specifications. The percentages in the mixture were as follows: 0.3 PVA and 0.7 MWP; and 0.4 PVA and 0.6 MWP, with MWP as the sole pigment; 0.25 PVA, 0.175 YSP (yellow soil pigment) and 0.575 MWP; and 0.35 PVA, 0.175 YSP and 0.475 MWP, of YSP and MWP; and 0.25 PVA, 0.175 RSP (red soil pigment) and 0.575 MWP, of RSP and MWP. The weatherability test showed that MWP addition to the paint formula contributed to increased paint durability and improved photolytic stability. Thus, the results indicate that marble waste, as an active pigment or mineral filler, is a promising alternative for producing building paint.

Layered double hydroxide (LDH) of calcium and aluminum (HC) intercalated with the dodecyl sulfate (DS) was examined in the simultaneous removal of divalent metal (Cu2+) and anionic (methyl orange - MO) and cationic (methylene blue - MB) dyes, as compound model in aqueous solutions. The HC-DS was characterized by infrared spectroscopy (IR), Raman spectroscopy, X-ray diffractometry (XRD) and atomic absorption spectrometry. The effects of the contact time, pH, Cu2+ and dyes concentration were evaluated. The 104−HC-DS allowed the complete removal (100%) of Cu2+ (0.75 mmol L−1) by layered reconstruction, forming the CuAl-LDH containing DS what simultaneously removes 92% of MO and 90% of the MB (0.05 mmol L−1) contained in the same solution. The results obtained showed that HC-DS has great potential to be used in treatment of solutions containing divalent metals and/or dyes.

In this work, monolacunary Keggin heteropolyacid salts containing sodium as the countercation were synthesized and evaluated as catalysts on the camphene oxidation with hydrogen peroxide. Under reaction conditions (i.e., 333 K, air atmosphere, CH3CN solution), camphene (1) was selectively oxidized by H2O2, generating two rare products; camphene aldehyde (1a) and camphenylic acid (1b), which have attractive olfactive properties. Notably, these uncommon compounds were obtained with the camphene preserving their carbon skeletal. Among the lacunar Keggin heteropolyacid salts, the Na7PW11O39 lacunar salt was the most active and selective toward oxidation products, completely converting the camphene to (1a) and (1b) products. The catalyst load, the oxidant: camphene molar ratio and the reaction temperature allowed to control the (1a)/ (1b) proportion.

In this work, the activity of Sn(II)-Keggin heteropolyacid salts (i.e., Sn3/2PW12O40 and Sn3/2PMo12O40) was investigated on the etherification reactions of glycerol with tert-butyl alcohol. Tin(II) heteropoly catalysts were easily synthesized and characterized by analyses of FT-IR/ATR, TG/DSC, MEV/EDS, XRD, BET, and potentiometric titration with n-butylamine. The activity of heteropoly salts was compared to the precursor heteropolyacids and SnSO4 catalysts. The Sn3/2PW12O40-catalyzed etherification achieved the highest tert-butyl glycerol ethers selectivity (ca. 90%) after 4 h of reaction at 363 K. The selectivity toward mono-glyceryl tert-butyl ether (i.e., an efficient surfactant) or di-tert-butyl glyceryl ether (i.e., a fuel bioadditive) can be tailored by an adequate adjustment of the reaction parameters (i.e., catalyst loading, reactant stoichiometry). Glycerol ethers were characterized by 1H and 13C NMR and infrared spectroscopy and mass spectrometry.

Adhesion of Salmonella Enteritidis to lettuce leaves cultivated in hydroponic or conventional systems was evaluated in the context of competitive microflora and physicochemical characteristics of leaves. A thermodynamic study based on the determination of the total free energy of surface interactions was conducted to predict pathogen leaf adhesion. A higher number of S. Enteritidis adhered to the lettuce leaves cultivated in a hydroponic system (p Δ G sws > 0 ). Lettuce cultivated in a hydroponic system presented a negative (hydrophobic) free energy value ( Δ G sws 0 ). Adhesion of S. Enteritidis to lettuce surfaces was thermodynamically unfavourable, independent of the cultivation method ( Δ G adhesion > 0 ). Thus, the thermodynamic evaluation explains the low number of S. Enteritidis cells that adhered to the lettuce leaves. There was a relationship between the number of S. Enteritidis adhering to the lettuce leaves and the physicochemical characteristics of the microbial and vegetable surfaces. Higher numbers of endogenous microorganisms found in the lettuce leaves from conventional system reduced S. Enteritidis adhesion. The study of the factors involved in bacterial adhesion to food surfaces is of great importance for contamination control and safe food maintenance.