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Universities are an example of institutions that aggregate people around work/study who consume water, energy and produce waste daily in their activities, generating an impact on the environment. The purpose of this study is to determine the quantity, composition and recycling potential of waste generated at the Faculdade UnB Planaltina (FUP) campus, of the University of Brasilia in the Federal District, Brazil, to develop a waste management strategy compatible with national legislation and sustainable global practices.

This study was based on conducting on-site visits to identify the sources of generation, hazardousness, management and gravimetric characteristics of residual waste from 2015 to 2016. In 2016, a selective collection was implemented on the FUP campus, and since then, actions to raise awareness for the selective disposal and monitoring of waste were conducted with the academic community.

The results showed that the campus generates 148 kg of waste/day, whereas the per capita generation is 92 g/day. The production of hazardous waste is related to campus laboratories which manage it under a specific program. The campus restaurant is the place that generates the most waste, of which organic waste is the most representative. When categorizing the waste generated on campus, the authors found that the majority are recyclables at 67% of the total. This category includes material composed of cardboard, paper and plastic, all able to be recycled in the Federal District.

The recyclable waste generated at the FUP campus is being diverted from the city’s landfill because they are donated to a recycling cooperative. These actions promote income generation, social inclusion of waste pickers and a circular economy, all in compliance with the National Solid Waste Policy. As a result, the FUP campus is more in line with Brazilian legislation and the global context of adopting sustainable waste management amongst higher education institutions.

This paper contributes to the literature on sustainability in higher education by reporting the process of implementation of a waste management strategy in a university campus. Further, it presents tools and methods that can be used to achieve sustainability in waste management. The study also identifies that the crucial factor for the success of such actions is the mobilization and participation of the academic community in the process. It does so by presenting findings demonstrating how the University of Brasilia has been concerned with adopting pro-environmental measures for sustainable development.

The purpose of this paper is to evaluate how improvements in municipal solid waste management systems (MSWMS) can contribute to a transition toward circular economy (CE) in urban areas, outlining actions and guidelines for public policies.

The research was carried out in three municipalities located in the state of São Paulo in terms of: diagnosis; elaboration of more positive scenarios in terms of CE and scaling of economic and environmental benefits; and outline actions and guidelines for public policies of MSWMS.

In developing countries like Brazil, MSWMS can contribute to a transition toward a CE through new public policies and management practices, or even through the improvement of those that already exist. Examples of this are the integration of the informal sector of the recycling chain and service sector related to repairs of clothing, shoes, furniture and electronics as well as composting at the food production site. This could be strengthened by legal and financial mechanisms, training and carbon credit projects. Moreover, there is a need for integration of public policies between different levels of governments and sectoral policies.

This paper developed a methodology to examine the potential for a transition toward a CE through the MSWMS in different scenarios and cities. This methodology allows to advance the implementation of the concept of CE in urban areas of developing countries and generating co-benefits to the local economy and the global environment.

The purpose of this paper is to evaluate local biodegradable oils with long chain fatty acids namely: castor (Ricinus communis L.), jojoba (Simmondsia chinensis L.), olive (Oleo europaea L.), and sunflower (Helianthus annuus L.) oils for lubrication candidacy as a substitute to petroleum mineral oils.

Evaluation criteria includes antiwear, lubricity, and extreme pressure (load carrying capacity) using the four‐ball configuration, oxidation induction by pressure differential scanning calorimetry, thermal stability by thermo‐gravimetric analyses, and viscometry using relevant American Society of Testing and Materials (ASTM) standards.

The results show that the lubrication films at the interface failed by the decomposition of the metallic soaps formed by the chemical reaction of the constituent fatty acid molecules and the rubbing surfaces. The biodegradable oils show superior lubricant performance compared to the paraffin‐based mineral oil, despite their poor oxidation stability. Oxidation induction and thermo‐gravimetric characteristics of the biodegradable oils are closely related to their polyunsaturated and monounsaturated fatty acid composition.

The paper shows how these biodegradable oils could be used as good substitute for petroleum mineral oils in as‐received state or little antioxidant additives.

The purpose of this paper is to compare the performance of X‐ray fluorescence (XRF) instruments with different detector systems (proportional counter, positive intrinsic negative and Si drift detectors) for measuring thin Au and Pd coatings on printed circuit boards and to investigate different ways of background treatment. It also aims to provide and certify suitable reference materials which are similar to samples used in production.

XRF measurements were performed with different instruments and detector types. The quantification of the reference materials is based on XRF, gravimetric analysis and Rutherford backscattering (RBS).

The well‐established X‐ray instrumentation for coating thickness measurement, with proportional counter detectors, are not very suitable for measuring thin ( < approx. 100 nm) coatings of gold and palladium due to the poor energy resolution of the proportional counter‐tubes. Systems with semiconductor detectors achieve results that are more reliable with a significantly higher accuracy. A correct background treatment is especially important for very thin coatings. The composition of the base material has to be taken into account by the software evaluation algorithm for each measurement. A global base subtraction performed prior to the measurement can achieve better repeatability, but can also lead to incorrect absolute values.

If small measuring spots (e.g. 150 μm) have to be realized with semiconductor detector systems, special X‐ray optics (polycapillaries) have to be used to obtain an intensity comparable to that offered by proportional counter devices. This will be the subject of a further publication.

The paper provides an overall review and results for different types of instruments (detectors) and compares different background treatments. Suitable reference materials have been developed for precise and traceable measurements. Their quantification is based on gravimetric analysis and RBS. The standard‐free energy dispersive X‐ray fluorescence (ED‐X‐ray fluorescence analysis (XRFA)) was used for interpolation of the gravimetric data for thin coatings. For the region below 100 nm, measurement uncertainties of less than 1 nm can be achieved.

The purpose of this study was to investigate cimetidine as corrosion inhibitor of aluminium in hydrochloric acid medium.

Cimetidine was characterized by gas chromatography mass spectrophotometer and Fourier transform infrared spectroscopy to determine its chemical composition and functional groups, respectively. Gravimetric, potentiodynamic polarization and electrochemical impedance spectroscopic techniques were used in the corrosion inhibition process. Thermodynamic and adsorption parameters were evaluated. And response surface methodology was used to optimize the corrosion inhibition process.

Analysis of the results revealed that major constituents of cimetidine include metronidazole, n-hexadecanoic acid cyclohexane and methyl ester. It has C-H stretch, C = N stretch, CH₃C-H bend, ring C = C stretch, -C-O-O stretch, N-H bend, C-O stretch and C-H bend as predominant functional groups. Adsorption of molecules of the inhibitor on the aluminium surface was spontaneous, and it followed mechanism of physical adsorption. Response surface methodology revealed that quadratic model adequately described the inhibition efficiency of cimetidine as function of inhibitor concentration, temperature and time. Chemical and electrochemical results are in agreement that the cimetidine is a viable corrosion inhibitor. Cimetidine was revealed as mixed-type inhibitor because it controlled both cathodic and anodic reactions.

Empirical and optimization studies of cimetidine drug as corrosion inhibitor of aluminium in hydrochloric acid medium were carried out. The research results can provide the basis for deploying drugs (with mucosal protective and antacid properties) for corrosion control of metallic structures.

This paper aims to investigate influence of extraction solvent on the efficacy of apricot pomace extract (APE) as a sustainable corrosion inhibitor for mild steel in sodium chloride solution.

The chemical profiles of the extracts were analyzed using gas chromatography–mass spectrometry. Total phenolic, total flavonoid content and antioxidant properties of the extracts were determined. Besides, gravimetric, potentiodynamic polarization and atomic force microscopy were used to study the corrosion inhibition. The effect of immersion period on inhibition efficiency was evaluated. The reaction mechanism of the inhibitor was also discussed.

Corrosion inhibition decreasing is in the following order: solution of 2-propanol/ethanol apricot pomace (E/PAPE) extract > ethanol (EAPE) > 2-propanol (PAPE). The gravimetric, polarization measurements and surface analysis revealed that the growth of inhibitory properties is prolonged, and corrosion rate reduction after 40–48 h of exposure was studied.

APEs play an important role in the corrosion inhibition of mild steel in sodium chloride solution. Moreover, its application is potentially possible in industries.

The results contribute to the integrated valorization of food waste.

The different compositions of the conversion/oxidation products of organic substances in solution were studied. The formation of polymerized flavanol-aldehyde adducts and oxidized quinone compounds or tautomers structures because of extract transformation in water causes main corrosion reduction in 40–48 h.

As there is a strong inducement to develop new colored inorganic materials to substitute the current industrial pigments that are based on toxic metals hazardous to health and the environment, the purpose of this paper is to invent environmentally benign rare earth-based colorants as viable alternatives to the traditional toxic pigment formulations. Herein, the authors developed a series of rare earth pigments having the general formula Ca0.1 Ln0.9 PO4 ( Ln = Y , Pr , mixed rare earth oxides, RE and Di). After studying all the optical properties, the authors have gone for some coloring application in plastic like PMMA.

The designed pigments were synthesized by traditional solid-state method. Stoichiometric amounts of each reagent were mixed in an agate mortar and the mixtures were calcined at optimized temperature 1000 °C for 4 h in electric furnace followed by auto–cooling. The samples were characterized by X-ray diffraction diffraction, UV–vis spectroscopy, scanning electron microscope (SEM), particle size distribution, color coordinates determination, acid/alkali test, thermo gravimetric (TG) analysis and CIE–1976 L*a*b* color scales. Among the various lanthanide ions and calcium ion as dopant, the pigment composition shows various hues ranges from green to yellow. The designed pigments consist of non–toxic elements and were further found to possess high thermal and chemical stability. The pigments were also found to be appropriate candidates for the coloration of polymer substrates like PMMA.

The present investigations establish that various color hues can be achieved by the incorporation of suitable chromophore metal ions like calcium in various rare earth host lattice by tuning of the band gaps. The coloring mechanism is based on the strong absorption of the pigments in the blue and red regions due to electronic transitions of the micro states of rare earth ion. The pigment composition shows various hues ranges from green to yellow. The coloring mechanism is based on the tuning of band gap by the dopant like calcium in various rare earth host lattice. In addition, this pigment was chemically and thermally stable. Finally, it has applied in plastics like PMMA.

Mechanism of the color appearance using band calculations and on possible applications of rare earth phosphate powders as pigments in plastics and paints have not been explored much. However, the properties of the Ca-doped rare earth phosphate implies that this material has a potential to be applied as a satisfactory pigment for coating or coloring except for glaze, which may cause a side reaction at high temperatures, especially taking into consideration the economics and ecologies. The possibility of Ca2+ incorporation in CePO4 with monazite structure-type has been established.

The designed pigments consist of non-toxic elements and were further found to possess high thermal and chemical stability. The pigments were also found to be appropriate candidates for the coloration of polymer substrates. Thus, the present environmental friendly pigment powders may find potential alternative to the classical toxic inorganic pigments for various applications.

There is a strong incentive to design new colorants based on inorganic materials to substitute for industrial pigments that are based on heavy elements hazardous to health and the environment. However, several industrial yellow pigments such as cadmium yellow (CdS), chrome yellow (PbCrO4) and nickel titanium yellow (TiO2-NiO-Sb2O3) contain the harmful elements (e.g. Cd, Pb, Cr and Sb) for the human body as well as the environment. The designed pigments consist of non-toxic elements and were further found to possess high thermal and chemical stability. The pigments were also found to be appropriate candidates for the coloration of polymer substrates. Thus, the present environmental friendly pigment powders may find potential alternative to the classical toxic inorganic pigments for various applications.

There is a strong incentive to design new colorants based on inorganic materials to substitute for industrial pigments that are based on heavy elements hazardous to health and the environment. However, several industrial yellow pigments such as cadmium yellow (CdS), chrome yellow (PbCrO4) and nickel titanium yellow (TiO2-NiO-Sb2O3) contain the harmful elements (e.g. Cd, Pb, Cr and Sb) for the human body as well as the environment. So, the authors have developed new class of inorganic pigments that are both non-toxic and environmentally unimpeachable, while preserving or even exceeding the optical, thermal and chemical characteristics of the existing commercial pigments. The developed colorants find practical applications in polymer matrix like PMMA.

This paper aims to introduce a high-temperature grease design method assisted by back propagation neural network (BPNN) and verify its application value.

First, the grease data sets were built by sorting out the base data of greases in a large number of literatures and textbooks. Second, the BPNN model was built, trained and tested. Then, the optimized BPNN model was used to search the unknown data space and find the composition of greases with excellent high-temperature performance. Finally, a grease was prepared according to the selected composition predicted by the model and the high-temperature physicochemical performance, high-temperature stability and tribological properties under different friction conditions were investigated.

Through high temperature tribology experiments, thermal gravimetric analysis and differential scanning calorimetry experiments, it is proved that the high temperature grease prepared based on BPNN has good high-temperature performance.

To the best of the authors’ knowledge, a new method of designing and exploring high-temperature greases is successfully proposed, which is useful and important for the industrial applications.

In Brazil, studies on dietary fiber consumption are scarce. The greatest difficulty is to obtain reliable data on the fiber content of foods that are part of Brazilians’ eating habits, which involves adjusting laboratory methodology. It is extremely important to evaluate the average daily fiber intake on a regional basis, considering the heterogeneous eating habits of the Brazilians. The study aims to estimate the average dietary fiber content of meals eaten in “by‐the‐kilo” restaurants.

The foods used in the preparation of 1,907 meals consumed during one month in four restaurants in the city of São Paulo were studied. Intake, nutritional composition, and fiber analyses focusing on average lunch intakes were performed based on the RDA and SBAN (Brazilian Food and Nutrition Society) recommendations. Intake and nutritional composition results were compared with the values of a control meal theoretically prepared. A total of 40 samples of preparations using fiber‐rich foods were analyzed and their dietary fibers and soluble and insoluble fiber fractions were determined by enzymatic‐gravimetric method.

The results showed that a lunch meal alone accounts for 69.2 per cent of the SBAN recommendation and 39.5 per cent of the maximum RDA for dietary fiber.

Foods served in “by‐the‐kilo” restaurants proved to be good sources of fiber, and their insoluble‐to‐soluble fiber ratios were similar to the recommendations.

The purpose of this paper is to investigate the inhibitive properties of black pepper extract (BPE) for aluminium in 1M hydrochloric acid (HCl) medium.

Gravimetric, electrochemical impedance spectroscopy, galvanostatic polarization, scanning electron microscopy with energy dispersive X-ray examinations (SEM-EDX) techniques were used to study the corrosion inhibitive study.

The gravimetric measurement indicates that inhibition efficiency shows direct proportional relation with concentration of inhibitor. The impedance results illustrates that there was a presence of protective layer of inhibitor adsorbed on the metal/solution interface. Polarization outcome showed that BPE is mixed type inhibitor. The existence of adherent layer of inhibitor on the Al surface was confirmed by SEM-EDX. Quantum chemical calculations were performed using the density functional theory at B3LYP/6-31G(d) level of theory to evaluate the activity of inhibitor molecules present in extract towards the corrosion inhibition of Al.

Due to the presence of large number of compounds in the extract, it becomes difficult to understand the most active compound responsible for inhibition. However, from gas chromatography mass spectrometry and quantum data, the approximation has been made that the major compound piperine present in the extract can be most probable component responsible for the inhibition activity. Further calculation of binding energy between Al and inhibitor molecules can be performed using Material Studio software.

The extract can be used in cleaning and etching solutions. It can be used to limit the loss of Al metal during etching process.

BPE can be used as a potential source of eco-friendly corrosion inhibitor for Al in HCl medium.