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Neotropical woody bamboos can be growing in a heterogeneous and diversifying forest, including mountain to lowland. Its a resource widely available that remains underutilised use. Brazil has about 165 species that can be found in its various biomes, but the presence of woody bamboo extends from Mexico to Argentina. Woody bamboo offers an opportunity to the diversification of biomass and develop new supply chains such as biobased products, advanced biofuels, and efficient biorefineries. The tropical Americas have great potential to develop productive systems of bioenergy and industrial materials through biomass conversion techniques from high-productivity woody bamboos obtained through agroforestry and/or in degraded areas under recovery. A review of the current status of neotropical bamboo value chains, and the potential of some native and exotic species is included, considering the implementation of environmental protection and restoration initiatives and biodiversity conservation. Conversion technologies are discussed based on physicochemical properties of primary and residual biomass from bamboo species. The knowledge about neotropical woody bamboo is discussed, highlighting the advantages, limitations and gaps, besides the technological challenges, to consolidate a point of view that can represent the potential of these native species of bamboo as bio-based products and bioenergy feedstock.

Biochar materials have been applied in energy storage due to their unique properties, such as high storage of ions, high conductivity, chemical stability and ease of production. Combining it with the high specific capacitance could be a promising strategy to develop devices and improve the properties. Through a hydrothermal technique the biochar powders were synthesized from sugarcane biomass. An acid pretreatment was carried out before and after the graphitization process aiming to obtain carbon materials with high surface area and porosity. The morphological characterization reveals powders with pores of submicrometer diameter. For the pure biochar it was determined a superficial area of 477.66 m2.g−1 with a median pore size of 42.92 Å and a pore volume of 0.21 cm3.g−1. A carbon-based paste was then prepared to deposit on nickel foam and obtain the electrodes. In a 3-electrode system characterization, biochar has showed higher specific capacitance than the metal oxide composites due to higher surface area and higher medium pore diameter. It was calculated a resistance of 2.7 Ω, a capacitance of 446 mF.g−1, a power density of 46.2 W.kg−1 and an energy density of 1.8 W.h.kg−1. These results indicate the potential use of biochar-based electrodes with high electrical conductivity and improved surface area to obtain higher capacitance properties for development of advanced devices.

Transformers can produce gases dissolved in oil that can cause damage to their structures, and preventing failures caused by these gases is a goal to be reached. There is a demand for wireless sensors to monitor those gases. Alongside its development, there is a growing interest in new energy sources enabling these technologies. Triboelectric nanogenerators can gather energy from the environment, such as mechanical energy from vibrations, and convert it into electricity from the contact of two dielectric materials. In this work, the authors propose the study of a low-cost and straightforward triboelectric nanogenerator (TENG) based on ZnO nanorods as a positive dielectric material, with PDMS:GO composites at different concentrations as the negative dielectric material. All the studies were carried out in a wide frequency range varying from 45 to 250 Hz. Additionally, an analysis of the addition of a steel spring into the TENG to improve the device’s generating output is shown. A power density of 246 mV m−2 and 4 V of the output voltage was obtained using a PDMS:GO 4% (w/w) composite and a steel spring. A correlation between the “mass-spring” system and the better performance of the triboelectric device is presented. Further, vibration frequencies in several external points of the transformer walls and the device’s performance in these frequencies are shown, and the results gathered from this data are discussed.

Resumo Os modelos de sistemas de gestão de responsabilidade social foram desenvolvidos para atender às demandas de organizações na implantação de práticas de gestão que sejam efetivas nas melhorias das relações com as partes interessadas, na melhoria da performance organizacional na dimensão da responsabilidade social e na promoção da sustentabilidade organizacional. Neste trabalho são analisados os principais modelos de gestão de responsabilidade social, desenvolvidos na forma de normas, certificáveis ou não, que foram comparadas quanto a origens, objetivos e conteúdo, incluindo uma análise da contribuição destas na melhoria da qualidade de vida no trabalho.

As discussões sobre a utilização de tecnologias mais limpas em todos os segmentos de mercado vêm ganhando força no mundo atual. A indústria de embalagens, por estar relacionada ao aumento crescente na geração de resíduos sólidos, torna-se um foco importante na busca pelo desenvolvimento sustentável. A indústria de bebidas vem sofrendo profundas transformações quanto à escolha da matéria-prima utilizada nas embalagens, em que vasilhames retornáveis vêm sendo substituídos por descartáveis. Daí a necessidade de estudos de Avaliação de Ciclo de Vida, a fim de orientar a própria indústria, consumidores e políticas governamentais na busca de embalagens ambientalmente mais adequadas. Neste trabalho se buscou a comparação entre as garrafas de vidro e de PET, com volume de 600 ml, quanto ao gasto energético relativo ao transporte no estado de São Paulo, incluindo-se a distribuição do produto e a destinação final. Concluiu-se que as garrafas plásticas, apesar de seu baixo peso, têm um gasto energético no transporte maior que as de vidro, quando adicionados os gastos com a destinação final da embalagem, para uma distância de distribuição do produto de até 175 km.

Purpose: Thermal and Physicochemical evaluation of açaí seeds for its use in thermochemical conversion processes for clean energy generation. Methodology: Experimental and qualitative research, using analyzes such as: Thermal analysis (TG/DTG and DTA curves) and Calorimetry, Ultimate and Proximate analyzes, Scanning Electron Microscopy, Energy Dispersive Spectroscopy, X-Ray Diffraction, Fourier Transform Infrared Spectroscopy and Optical Emission Spectroscopy - Inductively Coupled Plasma. Findings: It was noted that the açaí seeds presented carbon, hydrogen, and oxygen contents as majority elements and a Higher Heating Value (HHV) of 19.8 MJ kg-1. Nitrogen and lead elements were found as trace elements. However, highly polluting elements, e.g., sulfur, cadmium and arsenic were not detected in the samples. Originality: The utilization of açaí seeds by means of thermoconversion processes for bioenergetic purposes can be an attractive socioenvironmental, reducing disposal in inappropriate places, adding considerable value to waste and still protecting the environment.