22 research outputs found
Mogućnost primjene ekološki prihvatljivoga anhidrida limunske kiseline, taninskolimunske kiseline i ricinoleinske kiseline kao ljepila za proizvodnju iverica srednje gustoće (MDP) bez formaldehida
Particles of flooded gum (Eucalyptus grandis) were bonded using three bio-based adhesives - anhydrous citric acid (CA), tannin-citric acid (TCA) and ricinoleic acid (RA) - from renewable sources and hot pressed to produce medium density particleboard (MDP). The bonding capacity of such adhesives and properties of the MDP were evaluated and compared to the requirements of seven grades of particleboards, according to the EN 312 (2010) standard. The RA did not create adhesion reaction with the wood particles. Adhesives formulated with CA and TCA presented capacity to bond eucalyptus particles into MDP confirmed by esterification reactions of the FTIRS analysis. MDP bonded with CA met requirements as high as grade P5 of the EN 312 (2010) standard for static modulus of elasticity (MOE) and internal bond (IB) and P2 for modulus of rupture (MOR). Panels bonded with TCA met requirements up to grade P3 for MOE, however, did not withstand water absorption.Za izradu iverice srednje gustoće (MDP) upotrijebljeno je iverje drva eukalipta (Eucalyptus grandis) lijepljeno trima ekološki prihvatljivim ljepilima dobivenim iz obnovljivih izvora na bazi anhidrida limunske kiseline (CA), taninsko-limunske kiseline (TCA) i ricinoleinske kiseline (RA) te prešano u vrućoj preši. Kvaliteta lijepljenja tim ljepilima i svojstva iverice ocijenjeni su usporedbom sa sedam klasa uporabe prema normi EN 312 (2010). Ljepilo RA nije uspjelo povezati drvno iverje. Ljepila CA i TCA pokazala su sposobnost lijepljenja eukaliptova iverja pri izradi MDP ploče, što je potvrđeno reakcijom esterifikacije u FTIR analizi. MDP ploča izrađena primjenom CA ljepila udovoljava visokim zahtjevima klase uporabe P5 prema EN 312 (2010) za modul elastičnosti (MOE) i čvrstoću na raslojavanje (IB) te klase P2 za modul loma (MOR). Ploče izrađene uporabom TCA ljepila ispunile su zahtjeve klase uporabe P3 za modul elastičnosti (MOE), ali nisu zadovoljile zahtjeve o upijanju vode
Obtaining hydrochar via hydrothermal carbonization of Magonia pubescens A. St. Hil. Sapindaceae fruit bark : characterization and evaluation of its adsorptive properties
A Carbonização hidrotermal (HTC) de cascas do fruto de Magonia pubescens A. St. Hil. Sapindaceae (Tingui do cerrado) é apresentada como uma proposta inédita na produção de hydrochars a partir de precursores de espécies do Cerrado Brasileiro, onde se verificou a influência da temperatura nas propriedades dos materiais obtidos. Os hyrochar obtidos foram caracterizados em termos de rendimento em peso, análise elementar e estimativa do poder calorífico superior (PCS), análise de espectroscopia na região do infravermelho (FT-IR), difratometria de raios-x (DRX) e avaliação da capacidade de adsorção. O aumento da temperatura afetou negativamente o rendimento do hydrochar, o qual variou entre 46,25 % e 27,42%, nas temperaturas de 170 e 190 °C, respectivamente. Hydrochars com maior teor de carbono (64,10%) foram obtidos em baixa temperatura (170 °C), o qual também apresentou maior poder calorífico superior (23,94 MJ kg-1) e área superficial específica (44,0 m2.g-1). A evolução das razões atômicas H/C e O/C indicou processos de desidratação e descarboxilação durante a carbonização hidrotérmica. As isotermas de adsorção-dessorção de N2 a -176 ºC, resultantes da análise das propriedades texturais e estruturais, demonstraram a presença de mesoporos na estrutura dos hydrochars. Na avaliação da capacidade de adsorção com azul de metileno, a isoterma de Langmuir foi a que melhor explicou o comportamento de adsorção, tendo os hydrochars obtidos a 170 e 180 °C as maiores capacidades de adsorção (139,38 e 202,40 mg g-1, respectivamente). Os resultados indicaram a carbonização hidrotermal de cascas do fruto de tingui como uma nova estratégia para o desenvolvimento de hydrochars com alto rendimento, teor de carbono elevado e alta eficiência de adsorção, valores superiores a diversos trabalhos encontrados na literatura.The hydrothermal carbonization (HTC) of bark of the fruit of Magonia pubescens A. St. Hil. Sapindaceae (Tingui do Cerrado) presents as an unprecedented proposal for the production of hydrochars from precursors of Brazilian Cerrado species, where the influence of temperature on the properties of the obtained materials is verified. The obtained hydrochar were characterized in terms of yield, elemental analysis, estimation of the higher calorific value, infrared spectroscopy, X-ray diffractometry, and methylene blue adsorption. The temperature increases affected negatively hydrochar yield, which varied between 46,25% and 27,42%, at temperatures of 170 and 190 °C, respectively. Hydrochar with higher carbon content (64,10%), higher calorific value (23,94 MJ kg-1) and specific surface area (44,0 m2 g-1) were obtained at 170 °C. The evolution of the atomic ratios H/C and O/C indicated processes of dehydration and decarboxylation during hydrothermal carbonization. The adsorption-desorption isotherms of N2 at -176º C resulting from the analysis of the textural and structural properties demonstrated the presence of mesopores in the structure of the hydrochars. In the evaluation of the adsorption capacity with methylene blue, the adsorption data correlated well with the Langmuir isotherm. In this analysis, the hydrochars obtained at 170 and 180 °C demonstrated the highest adsorption capacity (Qmax = 139,38 and 202,40 mg g-1, respectively). The results indicated the hydrothermal carbonization of the bark of the tingui fruit as a new strategy for the development of hydrochars with high yield, high carbon content and high adsorption efficiency, higher values than several papers found in the literature
Obtenção de hydrochar a partir de carbonização hidrotérmica de cascas do fruto de Magonia pubescens A. St. Hil. Sapindaceae: Caracterização e avaliação em processo de adsorção
A Carbonização hidrotermal (HTC) de cascas do fruto de Magonia pubescens A. St. Hil. Sapindaceae (Tinguido cerrado) é apresentada como uma proposta inédita na produção de hydrochars a partir de precursoresde espécies do Cerrado Brasileiro, onde se verificou a influência da temperatura nas propriedades dos materiaisobtidos. Os hyrochar obtidos foram caracterizados em termos de rendimento em peso, análise elementar eestimativa do poder calorífico superior (PCS), análise de espectroscopia na região do infravermelho (FT-IR),difratometria de raios-x (DRX) e avaliação da capacidade de adsorção. O aumento da temperatura afetounegativamente o rendimento do hydrochar, o qual variou entre 46,25 % e 27,42%, nas temperaturas de 170 e190 °C, respectivamente. Hydrochars com maior teor de carbono (64,10%) foram obtidos em baixa temperatura(170 °C), o qual também apresentou maior poder calorífico superior (23,94 MJ kg-1) e área superficialespecífica (44,0 m2.g-1). A evolução das razões atômicas H/C e O/C indicou processos de desidratação e descarboxilaçãodurante a carbonização hidrotérmica. As isotermas de adsorção-dessorção de N2 a -176 ºC, resultantesda análise das propriedades texturais e estruturais, demonstraram a presença de mesoporos na estruturados hydrochars. Na avaliação da capacidade de adsorção com azul de metileno, a isoterma de Langmuirfoi a que melhor explicou o comportamento de adsorção, tendo os hydrochars obtidos a 170 e 180 °C as maiorescapacidades de adsorção (139,38 e 202,40 mg g-1, respectivamente). Os resultados indicaram a carbonizaçãohidrotermal de cascas do fruto de tingui como uma nova estratégia para o desenvolvimento de hydrocharscom alto rendimento, teor de carbono elevado e alta eficiência de adsorção, valores superiores a diversostrabalhos encontrados na literatura.Palavras-chave: Carbonização hidrotermal. Tingui do Cerrado. Adsorventes alternativos. Azul de metilen
Viral to metazoan marine plankton nucleotide sequences from the Tara Oceans expedition
A unique collection of oceanic samples was gathered by the Tara Oceans expeditions (2009–2013), targeting plankton organisms ranging from viruses to metazoans, and providing rich environmental context measurements. Thanks to recent advances in the field of genomics, extensive sequencing has been performed for a deep genomic analysis of this huge collection of samples. A strategy based on different approaches, such as metabarcoding, metagenomics, single-cell genomics and metatranscriptomics, has been chosen for analysis of size-fractionated plankton communities. Here, we provide detailed procedures applied for genomic data generation, from nucleic acids extraction to sequence production, and we describe registries of genomics datasets available at the European Nucleotide Archive (ENA, www.ebi.ac.uk/ena). The association of these metadata to the experimental procedures applied for their generation will help the scientific community to access these data and facilitate their analysis. This paper complements other efforts to provide a full description of experiments and open science resources generated from the Tara Oceans project, further extending their value for the study of the world’s planktonic ecosystems
Viral to metazoan marine plankton nucleotide sequences from the Tara Oceans expedition
A unique collection of oceanic samples was gathered by the Tara Oceans expeditions (2009-2013), targeting plankton organisms ranging from viruses to metazoans, and providing rich environmental context measurements. Thanks to recent advances in the field of genomics, extensive sequencing has been performed for a deep genomic analysis of this huge collection of samples. A strategy based on different approaches, such as metabarcoding, metagenomics, single-cell genomics and metatranscriptomics, has been chosen for analysis of size-fractionated plankton communities. Here, we provide detailed procedures applied for genomic data generation, from nucleic acids extraction to sequence production, and we describe registries of genomics datasets available at the European Nucleotide Archive (ENA, www.ebi.ac.uk/ena). The association of these metadata to the experimental procedures applied for their generation will help the scientific community to access these data and facilitate their analysis. This paper complements other efforts to provide a full description of experiments and open science resources generated from the Tara Oceans project, further extending their value for the study of the world's planktonic ecosystems
Community-Level Responses to Iron Availability in Open Ocean Plankton Ecosystems
Predicting responses of plankton to variations in essential nutrients is hampered by limited in situ measurements, a poor understanding of community composition, and the lack of reference gene catalogs for key taxa. Iron is a key driver of plankton dynamics and, therefore, of global biogeochemical cycles and climate. To assess the impact of iron availability on plankton communities, we explored the comprehensive bio-oceanographic and bio-omics data sets from Tara Oceans in the context of the iron products from two state-of-the-art global scale biogeochemical models. We obtained novel information about adaptation and acclimation toward iron in a range of phytoplankton, including picocyanobacteria and diatoms, and identified whole subcommunities covarying with iron. Many of the observed global patterns were recapitulated in the Marquesas archipelago, where frequent plankton blooms are believed to be caused by natural iron fertilization, although they are not captured in large-scale biogeochemical models. This work provides a proof of concept that integrative analyses, spanning from genes to ecosystems and viruses to zooplankton, can disentangle the complexity of plankton communities and can lead to more accurate formulations of resource bioavailability in biogeochemical models, thus improving our understanding of plankton resilience in a changing environment
Efeito de frações tânicas sobre parâmetros biológicos e nutricionais de Spodoptera frugiperda (Lepidoptera: Noctuidae)
EVALUATION OF SORGHUM SILAGES OF DIFFERENT GENOTYPES WITH AND WITHOUT CONDENSED TANNINS
A total of 10 Sorghum cultivar: two lines (CMSXS114, T ) and (CMSXS165, WT ), six hybrids ( 9953101,T; 9953130,T; BR601, WT; BR701, T; BR700, T; and AG2005, WT and two varieties (BR501, WT; and BR506, WT) with 8 replications were ensiled in PVC silos of 3 kg per silo for 60 days and then analyzed for condensed tannins (CT) (colorimetric analysis by the butanol-HCl method), CP, NDF, ADF, and in vitro (IVDMD-24 and 48hs) digestibilities. Condensed tannins (CT) fromquebracho were purified using affinity chromatography with sephadex LH-20 and used as a standard. Low concentrations of CT have been defined as 10 g kg-1 DM or less and medium as 10 to 40 g kg-1 DM, and levels exceeding 40 g kg-1 DM as high. Hybrid 9953130 had the highest concentration of CT among the sorghum silages (P 0.09). The highest CP content was noted for line CMSXS165 (97.4 g kg-1; P < 0.05). Concentrations of CP in CMSXS114 (83.2 g kg-1), BR 700 (76.4 g kg-1), BR701 (80.5 g kg-1), and AG2005 (79.2 g kg-1) were above the overall mean (74.0 g kg-1). The in vitro digestibilities (24 and 48 hours) of the two isogenics lines CMSXS114 (T) and CMSXS165 (WT) were not different. We concluded that the CT level did not affect digestibility; however, relative CT concentrations were low. Therefore, we could not suggest significant effects of CT content on DM intake, digestibility levels or performance in cattle fed with any of these sorghum silages
Challenges and alternatives for the adequacy of hydrothermal carbonization of lignocellulosic biomass in cleaner production systems:a review
Abstract
Hydrothermal carbonization (HTC) is considered an attractive and constantly expanding eco-friendly methodology for thermochemical processing of different types of biomass in energy, carbonaceous materials, structured hybrids, and other chemical products. However, some challenges for the technique to be adequate in clean production need to be overcome. In this way, a comprehensive review is presented regarding the process variables, fundamentals, properties, possible uses of the products obtained and the challenges for cleaner production. This paper stands out in relation to those available in the literature when gathering exclusive information on hydrothermal carbonization with a focus on lignocellulosic biomass, the possibility of reusing the wastewater from HTC in recirculation processes and the challenges of the technique aiming at the sustainability of the process. Initially, we discuss the general concepts and reactional mechanisms involved in the methodology and then it explored the physical-chemical properties and possible applications of hydrochar, the modification methodologies and activation processes to obtain activated carbon in an eco-friendly approach. Current knowledge gaps and the overcoming of challenges such as the recirculation of the aqueous phase of hydrothermal carbonization are also discussed together with new perspectives and alternatives for the technique based on a biorefinery system, in order to enable a wider exploration of hydrothermal carbonization of its great potential in a cleaner production concept