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2.
Sci Rep ; 11(1): 4899, 2021 03 01.
Article in English | MEDLINE | ID: mdl-33649387

ABSTRACT

The use of wood panel residues as biomass for energy production is feasible. Heat treatments can improve energy properties while minimizing the emission of toxic gases due to thermoset polymers used in Medium Density Fiberboard (MDF) panels. Torrefaction or pre-carbonization, a heat treatment between 200 and 300 °C with low oxygen availability accumulates carbon and lignin, decreases hygroscopicity, and increases energy efficiency. The objective of this work was to evaluate the energy parameters (immediate, structural, and elementary chemical composition, moisture content, and yield) and density in torrefied MDF panels. The torrefaction improved the energetic features of coated MDF, decreasing the moisture content, volatile matter, and consequently, concentrating the carbon with better results in the samples torrefied for 40 min. The densitometric profiles of the torrefied MDF, obtained by X-ray densitometry, showed a decrease in the apparent density as torrefaction time increased. The digital X-ray images in gray and rainbow scale enabled the most detailed study of the density variation of MDF residues.

3.
Sci Rep ; 11(1): 900, 2021 01 13.
Article in English | MEDLINE | ID: mdl-33441628

ABSTRACT

Pellets are widely used for power generation because they use renewable raw material with easy storage, transport and high energy density. However, the structural fragility, disintegrating during handling, transport and storage, is one of the main problems of pellets, but the addition of binders/additives can minimize this fragility. The objective of this study was to evaluate the properties of wood pellets with the addition of starch (corn and wheat) and kraft lignin in different proportions. Pellets were produced with the addition of starch (wheat and corn) and kraft lignin in the proportions of 1, 2, 3, 4 and 5% in relation to the mass of wood particles of Pinus sp., with 12% moisture (dry basis), classified in 3 and 1 mm sieves and compacted in a pelleting press in the laboratory, according to European standard EN 14961-2. Physical and mechanical properties of the pellets were evaluated and their densitometric profiles obtained from the Faxitron LX-60 X-ray equipment. Corn starch and kraft lignin additives at 4% improved pellet properties (density, fines and hardness), reducing their losses during handling, storage and transport.

4.
ACS Appl Energy Mater ; 4(11): 12789-12797, 2021 Nov 22.
Article in English | MEDLINE | ID: mdl-35128339

ABSTRACT

Microcapsules loaded with n-docosane as phase change material (mPCMs) for thermal energy storage with a phase change transition temperature in the range of 36-45 °C have been employed to impregnate cotton fabrics. Fabrics impregnated with 8 wt % of mPCMs provided 11 °C of temperature buffering effect during heating. On the cooling step, impregnated fabrics demonstrated 6 °C temperature increase for over 100 cycles of switching on/off of the heating source. Similar thermoregulating performance was observed for impregnated fabrics stored for 4 years (1500 days) at room temperature. Temperature buffering effect increased to 14 °C during heating cycle and temperature increase effect reached 9 °C during cooling cycle in the aged fabric composites. Both effects remained stable in aged fabrics for more than 100 heating/cooling cycles. Our study demonstrates high potential use of the microencapsulated n-docosane for thermal management applications, including high-technical textiles, footwear materials, and building thermoregulating covers and paints with high potential for commercial applications.

5.
J Gerontol Nurs ; 46(11): 37-47, 2020 Nov 01.
Article in English | MEDLINE | ID: mdl-33095891

ABSTRACT

The aim of the current study was to analyze the effectiveness and feasibility of a training program for care professionals at two nursing homes, investigating the impact on their beliefs, attitudes, and knowledge regarding aging. Twenty-three formal caregivers at a private nursing home and 10 formal caregivers at a philanthropic nursing home participated in the training program, which consisted of five weekly meetings, each lasting 1.5 hours. Characterization of the sample was performed and effectiveness and feasibility of the intervention were analyzed. The training program improved participants' knowledge about older adults; however, their attitudes and beliefs regarding old age were not affected. Results also indicated that the intervention program was feasible at both nursing homes. The positive results of the study underscore the importance of training and continuing education of professionals who work with older adults, especially staff at nursing homes. [Journal of Gerontological Nursing, 46(11), 37-47.].


Subject(s)
Geriatric Nursing , Nursing Care , Aged , Aging , Feasibility Studies , Humans , Nursing Homes
6.
Ecosyst People (Abingdon) ; 16(1): 197-211, 2020 Jul 13.
Article in English | MEDLINE | ID: mdl-32984823

ABSTRACT

The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services(IPBES) strengthens the science-policy interface by producing scientific assessments on biodiversity and ecosystem services to inform policy. IPBES fosters knowledge exchange across disciplines, between researchers and other knowledge holders, practitioners, societal actors and decision makers working at different geographic scales. A number of avenues for participation of stakeholders across the four functions if IPBES exist. Stakeholders come from diverse backgrounds, including Indigenous Peoples and local communities, businesses, and non-governmental organization. They represent multiple sources of information, data, knowledge, and perspectives on biodiversity. Stakeholder engagement in IPBES seeks to 1. communicate, disseminate, and implement the findings of IPBES products; 2. Develop guidelines for biodiversity conservation within member countries; and 3. create linkages between global policy and local actors - all key to the implementation of global agreements on biodiversity. This paper reflects on the role of stakeholders in the first work programme of IPBES (2014-2018). It provides an overview of IPBES processes and products relevant to stakeholders, examines the motivation of stakeholders to engage with IPBES, and explores reflections by the authors (all active participants on the platform) for improved stakeholder engagement and contributions to future work of the platform.

7.
Chemistry ; 22(13): 4389-94, 2016 Mar 18.
Article in English | MEDLINE | ID: mdl-26864874

ABSTRACT

We have encapsulated the heat exchange material, n-docosane, into polyurethane capsules of different sizes. Decreasing the size of the capsules leads to changes of the crystallinity of phase-change material as well as melting/crystallization temperature. The novelty of the paper includes 1) protection of the nanostructured energy-enriched materials against environment during storage and controlled release of the encapsulated energy on demand and 2) study of the structure and surface-to-volume properties of the energy-enriched materials dispersed in capsules of different sizes. The stability of energy nanomaterials, influence of capsule diameter on their energy capacity, homogeneity and operation lifetime are investigated.

8.
Chemistry ; 21(31): 11174-9, 2015 Jul 27.
Article in English | MEDLINE | ID: mdl-26119217

ABSTRACT

Polyurethane microcapsules were prepared by mini-emulsion interfacial polymerization for encapsulation of phase-change material (n-docosane) for energy storage. Three steps were followed with the aim to optimize synthesis conditions of the microcapsules. First, polyurethane microcapsules based on silicone oil core as an inert template with different silicone oil/poly(ethylene glycol)/4,4'-diphenylmethane diisocyanate wt % ratio were synthesized. The surface morphology of the capsules was analyzed by scanning electronic microscopy (SEM) and the chemical nature of the shell was monitored by Fourier transform infrared spectroscopy (FT-IR). Capsules with the silicone oil/poly(ethylene glycol)/4,4'-diphenylmethane diisocyanate 10/20/20 wt % ratio showed the best morphological features and shell stability with average particle size about 4 µm, and were selected for the microencapsulation of the n-docosane. In the second stage, half of the composition of silicone oil was replaced with n-docosane and, finally, the whole silicone oil content was replaced with docosane following the same synthetic procedure used for silicone oil containing capsules. Thermal and cycling stability of the capsules were investigated by thermal gravimetric analysis (TGA) and the phase-change behavior was evaluated by differential scanning calorimetry (DSC).


Subject(s)
Alkanes/chemistry , Capsules/chemistry , Polyurethanes/chemistry , Drug Compounding , Isocyanates/chemistry , Phase Transition , Silicone Oils/chemistry , Temperature
9.
Ann Clin Microbiol Antimicrob ; 13: 41, 2014 Aug 20.
Article in English | MEDLINE | ID: mdl-25139679

ABSTRACT

BACKGROUND: The use of antimicrobial solutions has been recommended to disinfect demineralized dentin prior to placing the filling material. The aim of this study was to evaluate the ability of several antimicrobials in controlling Streptococcus mutans (SM) biofilm formed in dentin. METHODS: Antimicrobial activity of 0.2% and 2% chlorhexidine (CHX), 0.2% cetrimide (CTR) and 0.2%, 0.5%, 1% and 2% alexidine (ALX) was assayed on 1-week SM biofilm formed on standardized coronal dentin blocks. Results of SM biofilm antimicrobial activity by different protocols were expressed as the kill percentage of biofilm and the term "eradication" was used to denote the kill of 100% of the bacterial population. To compare the efficacies of the different protocols the Student t test was used, previously subjecting data to the Anscombe transformation. RESULTS: All ALX concentrations tested and 0.2% CTR achieved a kill percentage higher than 99%, followed by 2% CHX with percentages above 96% (no statistically significant difference among them). Whereas 2% ALX and 0.2% CTR respectively showed eradication in 10 and 9 of the twelve specimens, 0.2% CHX did not produce eradication in any case. CONCLUSIONS: The present study shows that, when used for one minute, 2% and 1% alexidine, and 0.2% cetrimide, achieve eradication of Streptococcus mutans biofilm in most specimens when applied to a dentin-volumetric model.


Subject(s)
Anti-Bacterial Agents/pharmacology , Biguanides/pharmacology , Biofilms/drug effects , Cetrimonium Compounds/pharmacology , Chlorhexidine/pharmacology , Streptococcus mutans/drug effects , Streptococcus mutans/physiology , Cetrimonium , Dentin/microbiology , Dose-Response Relationship, Drug , Humans , Microbial Viability/drug effects , Time Factors
10.
Cien Saude Colet ; 18(4): 1009-18, 2013 Apr.
Article in Portuguese | MEDLINE | ID: mdl-23670378

ABSTRACT

This article analyzes the experience of the Permanent Workshop on Nutrition and Health Education, which provides ongoing education on health and nutrition for school nutritionists and educators. In 2009, nutritionists, principals/management assistants, pedagogical coordinators, teachers and nutrition undergraduates attended 10 workshops, which were based on Freire and Pichon-Rivière´s framework theories. Data analysis was performed using the Discourse of the Collective Subject method. At the beginning of their participation in the OPEAS, the relationship between educators and nutritionists was distant and few interdisciplinary activities were conducted. Communication among the school team, collaborative work with involvement of the whole school community, inclusion of food and nutrition education in the curricula, and provision of food as the central pedagogical tool were considered central to the promotion of healthy nutrition. In the final evaluation four central ideas were highlighted defining OPEAS as being important for knowledge acquisition, a setting for reflection, an opportunity for integration and a platform for putting ideas into practice. Ongoing education should be implemented with school professionals aiming to foster actions to promote healthy nutrition at school.


Subject(s)
Food Services , Health Education , Nutritional Sciences/education , Schools , Brazil , Education
11.
J Biomed Nanotechnol ; 7(3): 446-9, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21830487

ABSTRACT

The aim of the present study was the characterization of a polymeric blend composed of PVP/PVAL that can be used to obtain a biocompatible hydrogel, appropriate as a controlled drug release system. Polymeric blends could be the solution for the creation of new hydrogel, due to the improvement of individual polymer properties. The PVP and PVAL are used as a biocompatible hydrogel because they present high water absorption the main required characteristics for the formation of a hydrogel. This absorption is favored by the presence of the nitrogen of PVP and the hydroxyl of PVAL, and also by the formation of cross-links. Although the PVAL is a synthetic polymer, it is used as a basic material for different applications in biomedicine, once it is non toxic and also not carcinogenic. For this reason, PVP and PVAL were chosen combining the high flexibility of PVP with the mechanical resistance of PVAL, since it will able to form more resistant films. The characterization of the films obtained by mixing mechanically PVP and PVAL at different concentration was carried through several tests as spectroscopy in the infrared region (FTIR), differential scanning calorimetry (DSC) and tensile strength. Increasing the PVAL concentration increases the interaction between the polymers. This can be justified by the results obtained with the tensile test and with the spectrum obtained with the film which contain 0.9 g of PVAL and 0.1 g of PVP that shows the bonds between the polymers.


Subject(s)
Drug Delivery Systems , Lactic Acid/chemistry , Polymers/chemistry , Polyvinyls/chemistry , Pyrrolidines/chemistry , Calorimetry, Differential Scanning , Polyesters
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