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ABSTRACT Polyurethanes (PU) were synthesized from lignin by first preparing a prepolymer from esterified sugar-based trihydroxyl compound xylaric acid and a 20 mol % excess of methylene diphenyl diisocyanate. The prepolymer was crosslinked with 5, 10, and 15 wt % of an industrial soda lignin, and polyethylene glycol was used to bring soft segments into the material structure. The total amount of bio-based starting materials was as high as 35%. Evidence for the reaction between the prepolymer and lignin was observed using Fourier transform infrared spectroscopic analysis and 13C nuclear magnetic resonance spectroscopy. The thermal properties of the materials were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The mechanical and viscoelastic properties of the materials were determined by dynamic mechanical analysis (DMA). The glass transition temperatures ( Tg) obtained from DSC and DMA showed a trend of increasing Tg with the increasing amount of lignin. A similar trend was observed with TGA for the increasing thermal stability up to 550oC with the increasing amount of lignin. The lignin-polyurethanes obtained were stiff materials showing high Young's modulus values. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39714. [ABSTRACT FROM AUTHOR]

This study provides an extensive investigation on the kinetics, combustion characteristics, and thermodynamic parameters of the thermal degradation of guinea grass (Megathyrsus maximus) in N2-pyrolytic and oxidative atmospheres. A model-fitting technique and three different iso-conversional techniques were used to investigate the kinetics of the thermal process, after which an analysis of the combustion characteristics and thermodynamic parameters was undertaken. Prior to this, experiments on the physico-chemical characterization, thermogravimetric, and spectroscopic analyses were carried out to provide insight into the compositional structure of the guinea grass. The volatile matter, fixed carbon, and total lignin contents by mass were 73.0%, 16.1%, and 21.5%, respectively, while the higher heating value was 15.46 MJ/kg. The cellulose crystallinity index, determined by XRD, was 0.43. The conversion of the GG in air proceeded at a relatively much higher rate as the maximum mass-loss rate peak in a 20 K/min read was −23.1 and −12.3%/min for the oxidative and the pyrolytic, respectively. The kinetics investigation revealed three distinctive stages of decomposition with their corresponding values of activation energy. The average values of activation energy (FWO) at the latter stages of decomposition in the pyrolytic processes (165 kJ/mol) were higher than those in the oxidative processes (125 kJ/mol)—an indication of the distinctive phenomenon at this stage of the reaction. The Coats–Redfern kinetic model revealed that chemical reactions and diffusional models played a predominant role in the thermal decomposition process of the GG. This study showed that the thermodynamic parameters varied with the conversion ratio, and the combustion performance increased with the heating rates. The use of GG as an energy feedstock is recommended based on the findings from this work. [ABSTRACT FROM AUTHOR]

Visual appeal of wood is as important as its structural integrity in outdoor applications. Discoloration and checking of wood favor the utilization of alternative materials for outdoor cladding and decking. Lignin depolymerization is one of the critical processes leading to weathering. In the present paper, the potential of different classes of surface protection agents has been assessed on loblolly pine ( Pinus taeda) impregnated with water repellents, organic UV inhibitors, and an organic biocide. The treated samples were exposed to predetermined doses of solar radiation in Eastern Oregon, and the chemical changes occurring on the surfaces were evaluated by FTIR spectroscopy. After 1-year exposure, lignin loss was complete on all surfaces; however, some treatments provided longer term protection than others. Organic UV light inhibitors were most effective in this regard. A petroleum-based water repellent with a melting point of 54-58°C also provided protection against lignin degradation. [ABSTRACT FROM AUTHOR]

Abstract: The preparation of hyperbranched polymers from a unique combination of commercially available A2, B3 and CB1 3-type monomers is presented. Direct melt condensation of aliphatic dicarboxylic acid (A2) to compounds having trihydroxy groups ((B3), triethanolamine) and trihydroxy-monoamino groups ((CB1 3), tris(hydroxymethyl)aminomethane) led to a series of hyperbranched polyesters with amine cores and amide linkages. Because of the monomers availability and simplicity of the synthetic process, hyperbranched poly(ester-amine-amide) (HBPEAA) materials can be readily scaled up. This approach was used to synthesize series of prepolymers with varying degree of branching (DB) and distance between branching points. Taking the advantage of reactivity differences of COOH with the NH2 and OH groups, the hyperbranched polymer with different arrangement of amide linkage along the network was synthesized. The influence of reaction conditions such as monomer compositions, temperature and mode of mixing on the polymerization was examined. The DB of the HBPEAA (0.46–0.63) was dependant on the synthetic route. The HBPEAA exhibited moderate molecular weights as determined by NMR and ESI-MS. Thermogravimetric analysis revealed that the prepolymers exhibit reasonable thermal stability. The synthesized prepolymer was successfully utilized to copolymerize with 40% lignin to form toughened elastomeric materials with tensile strength of 12 MPa, Young''s modulus of 33 MPa and 149% elongation. [Copyright &y& Elsevier]

Abstract: Combined characteristics of hydrogen bonded/cross-linked polymer networks based on lignin motifs have been developed. This new type of polymeric material was prepared from an industrial lignin and a highly branched poly(ester-amine) (HBPEA) obtained by melt polycondensation of 1,1,1-triethanolamine (TEA) and adipic acid (AA). The lignin-HBPEA polymers were shown to be insoluble in common organic solvents and were characterized by FTIR and NMR spectroscopies. Thermo-mechanical measurements showed that melt mixing HBPEA with 40% lignin results in a flexible and tough material (T g; 7.7 °C and E′ 3.5 GPa). The hydrogen bonding recognition was based on various hydroxyl groups in lignin and aliphatic ester groups from HBPEA. The extent of interactions could be controlled by varying the amount of lignin added. These networks were thermally reversible and have highly tunable mechanical properties that were controlled by the extent of interactions. High level of mechanical properties could be achieved through the addition of lignin-poly(ester-amine) covalent cross-links. This study shows that the poly(ester-amine) structure plays an important role in the thermo-mechanical properties. By varying the spacer length between lignin and tertiary amine unit, materials with various thermo-mechanical properties were also obtained from the same parent polymer backbone. [ABSTRACT FROM AUTHOR]

This study investigated weathering effects on polyvinyl chloride (PVC) based wood plastic composites (WPC), with a focus on the color and structure that is attributed to the material composition. It is directed towards quantifying the main chemical modifications, such as carbonyl and vinyl groups which are formed during weathering. These composites were subjected to three weathering regimes: exterior, accelerated xenon-arc, and accelerated UVA. The change in color was monitored using colorimetry. Fourier transform infrared spectroscopy was used to identify and quantify the chemical modifications (carbonyl formation and vinyl propagation) due to weathering. Additionally, scanning electron microscopy was employed to observe the physical morphological changes that occurred. The results showed that exterior and accelerated xenon-arc and UVA weathering regimes increased the degree of lightness, total color change, carbonyl concentration, and wood loss on the surfaces of the weathered composites. The increased carbonyl concentration during weathering implied that degradation had occurred by oxidation process. Also, oxidation and lignin (from the wood) degradation influenced the color (lightness) of PVC based WPC upon weathering. [ABSTRACT FROM AUTHOR]

The effects of weathering on the constituents of wood and polymer matrix behavior in wood plastic composites (WPCs) were investigated. WPCs were produced from pine, extractives-free pine, and pine holocellulose fibers (60%) together with HDPE (40%). These composites were subjected to xenon-arc accelerated and outside weathering for a total of 1200 h and 120 days, respectively. The color and chemical changes that occurred on the surface of the WPCs were analyzed using a set of analytical techniques. For pine and extractive-free pine filled composites, the results showed that the total color change, lightness, and oxidation increased, while the lignin content decreased. In addition, the weight average molecular weight ( Mw) and number average molecular weight ( Mn) of extracted HDPE decreased with an increase in exposure time of the composites. However, HDPE crystallinity increased with longer exposure time. Lightness of holocellulose-based WPC changed the least while the change in its HDPE crystallinity was not significant compared to the other composite types. Therefore, holocellulose-based WPC may be preferred for applications where color stability is of high priority. [ABSTRACT FROM AUTHOR]

New approaches for assessing wood durability are needed to help categorize decay resistance as timber utilization shifts towards plantations or native forest regrowth that may be less durable than original native forest resources. This study evaluated attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy combined with principal component analysis (PCA) for distinguishing between groups of Alaska yellow cedar (Cupressus nootkatensis) wood for susceptibility to two decay fungi (Gloeophyllum trabeum and Rhodonia placenta) and the eastern subterranean termite (Reticulitermes flavipes). Alaska yellow cedar durability varied with test organisms, but the majority of samples were highly resistant to fungal and termite attack. Weight losses and extractives yield using sequential extractions (toluene:ethanol > ethanol > hot water) showed moderate to weak relationships. PCA analysis revealed limited ability to distinguish amongst levels of wood durability to all tested organisms. The absence of non-resistant samples may have influenced the ability of the chemometric methods to accurately categorize durability. [ABSTRACT FROM AUTHOR]

Global demand for transportation fuels is projected to increase 40% by 2040, and biomass-derived fuels (biofuels) play a crucial role in substituting fossil fuels and mitigating greenhouse gas emissions. Currently, biofuels are mainly consumed as blendstocks combined with petroleum-based fuels, and effective conversion technologies can address the quality challenges for offering standalone biofuels. Thermochemical conversion process is one of the most promising pathways among existing technologies for biofuel production. However, the major barriers are unwanted characteristics (e.g., thermal instability) of intermediate products, such as bio-oil, and required upgrading treatments for producing compatible fuels. This study highlights the merits and critical challenges of thermochemical conversion and physicochemical upgrading technologies for bio-blendstock production from lignocellulosic biomass. The novelty of this study lies in potential directions for future research through both critical and systematic literature reviews, and the proposed intensified process for lignocellulosic-based fuel blendstocks production. It is concluded that recovery and fractionation strategies (e.g., quenching and stripping) can maximize process yields and add values in the efficient conversion pathways. Effective quenching can stop secondary free radical reactions and improve liquid yields over gas and solid yields. Stripping process can improve process yield, catalyst lifespan, and thermal stability. It is further concluded that physicochemical treatments are not as effective as thermochemical treatments, but have advantages of mild operating conditions and potential for integrated solutions in conjunction with other treatments. [Display omitted] • This study reviews biomass conversion and bio-oil upgrading advancements. • Current thermochemical technologies and techniques are analyzed. • Process challenges are identified, and potential solutions are provided. • An intensified conversion and upgrading process is proposed. [ABSTRACT FROM AUTHOR]

Abstract: The effects of outside and accelerated (xenon-arc and UVA) weathering on the visual appearance and chemical changes of wood plastic composite (WPC) formulations based on high density polyethylene (HDPE) and polypropylene (PP) were investigated. Colorimetry, scanning electron microscopy, Fourier transform infrared spectroscopy (FT-IR), and pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS) were employed in this study. The study showed that for both outside and accelerated weathering, longer exposure time increased the degree of color change (and lightness), carbonyl concentrations, and wood loss on weathered WPC surfaces. HDPE-based WPC exhibited decreased lightening, carbonyl concentrations, and wood content loss when compared to PP-based WPC. From this study, relationships between chemical and color changes that occurred during exterior weathering of HDPE-based WPC were established. Oxidation and degradation of wood lignin influenced WPC color changes (lightening) during weathering. [Copyright &y& Elsevier]

Biologically derived polyesters known as polyhydroxyalkanoates (PHAs) represent a potentially "sustainable" replacement to fossil‐fuel‐based thermoplastics. However, current commercial practices that produce PHA with pure microbial cultures grown on renewable, but refined, feedstocks (i.e., glucose) under sterile conditions do not represent a sustainable commodity. Here, we report on PHA production with a mixed microbial consortium indigenous to an activated sludge process on carbon present in municipal wastewaters. Reactors operated under anaerobic/aerobic and aerobic‐only mode and fed primary solids fermenter liquor maintained a mixed microbial consortium capable of synthesizing PHA at 10 to 25% (w/w), while reducing soluble COD by approximately 62 to 71%. More critically, an aerobic batch reactor seeded from the anaerobic/aerobic reactor and fed fermenter liquor achieved approximately 53% PHA (w/w). Results presented suggest that environmentally benign production of biodegradable polymers is feasible. We further used PHA‐rich biomass to produce a natural fiber‐reinforced thermoplastic composite that can be used to offset advanced wastewater treatment costs. [ABSTRACT FROM AUTHOR]

Tracheid and sclereid differentiation was induced in callus cultures of Pinus radiata D. Don by culturing on a basal medium containing activated charcoal but no phytohormones; sclereids differentiated in callus derived from xylem strips, but not in callus derived from hypocotyl segments. The tracheids differentiated in hypocotyl-derived callus had helical, scalariform, reticulated or pitted secondary cell-wall patterns, but those differentiated in xylem-derived callus had a reticulate or pitted pattern. The thickened tracheid and sclereid walls contained lignin as indicated by the red colour reaction given with phloroglucinol-HCI. The presence of lignin in the cell walls of differentiated callus was confirmed using pyrolysis gas chromatography- mass spectrometry by the detection of phenylpropanoid components derived from lignin. Lignin was also detected using solid-state 13C cross-polarisation/magic-angle spinning nuclear magnetic resonance spectroscopy and quantified as thioglycolic acid lignin. Monosaccharide analyses of the cell walls isolated from differentiated and undifferentiated calli showed that the cell walls of the differentiated calli contained higher proportions of glucose and mannose, consistent with the presence of greater proportions of gluco- and/or galactoglucomannans in the secondary cell walls of the differentiated cells. A protocol for the stable transformation of undifferentiated, xylem-derived cultures was successfully developed. Transgenic cell lines were established following Biolistic particle bombardment with a plasmid containing the coding region of the nptII gene and the coding region of the cad gene from P. radiata. Expression of the nptII gene in transgenic lines was confirmed by an NPTII-enzyme-linked immunosorbent assay. The overexpression of cad in the transgenic lines resulted in a down-regulation of cinnamyl alcohol dehydrogenase (EC 1.1.1.195) expression. [ABSTRACT FROM AUTHOR]

More than 23 million tonnes of lignin are produced annually in the US from wood pulping and 98% of this lignin is burnt. Therefore, creating products from lignin, such as plastics, offers an approach for obtaining sustainable materials in a circular economy. Lignin-based copolymers were synthesized using a single pot, solvent free, melt condensation reaction. The synthesis occurred in two stages. In the first stage, a biobased prepolymer consisting of butanediol (BD, 0.8–1 molar content) and a diacid (succinic (SA), adipic (AA) and suberic acids (SuA), with varying amounts of diaminobutane (DAB, 0–0.2 molar content) was heated under vacuum and monitored by Fourier transform infra-red (FTIR) spectroscopy and electrospray ionization-mass spectrometry (ESI-MS). In the second stage, prepolymer was mixed with a softwood kraft lignin (0–50 wt.%) and further reacted under vacuum at elevated temperature. Progression of the polymerization reaction was monitored using FTIR spectroscopy. The lignin-copolyester/amide properties were characterized using tensile testing, X-ray diffraction (XRD), dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques. Lignin co-polymer tensile (strength 0.1–2.1 MPa and modulus 2 to 338 MPa) properties were found to be influenced by the diacid chain length, lignin, and DAB contents. The lignin-copolymers were shown to be semi-crystalline polymer and have thermoplastic behavior. The SA based copolyesters/amides were relatively stiff and brittle materials while the AA based copolyesters/amides were flexible and the SuA based copolyesters/amides fell in-between. Additionally, > 30 wt.% lignin the lignin- copolyesters/amides did not exhibit melt behavior. Lignin-co-polyester/amides can be generated using green synthesis methods from biobased building blocks. The lignin- copolyesters/amides properties could be tuned based on the lignin content, DAB content and diacid chain length. This approach shows that undervalued lignin can be used in as a macromonomer in producing thermoplastic materials. [ABSTRACT FROM AUTHOR]

Discusses the separation of lipopolysaccharides from phenol-water extraction of cells of Campylobacter jejuni serotype O:19 into a water-soluble component. Acetic acid hydrolysis of the ketosidic linkages to lipid A; Structural investigations of O-deacetylated lipopolysaccharides.

Examines the liberation of an O antigenic polysaccharide from the lipopolysaccharide extracted from Campylobacter jejuni serotype O:19 by acetic acid hydrolysis of the ketosidic linkage to lipid A. Techniques used to establish the structure of the polysaccharide; Glycan as a derivative of hyaluronic acid; Parallel experiments on O antigens.

Complete structures, including the location of N-acetylneuraminic acid (Neu5Ac) residues, were assigned for the core regions of Campylobacter jejuni serotypes O:1, O:4, and O:23 and O:36 lipopolysaccharides (LPS). In continuation of earlier studies, structure determinations of liberated oligosaccharides and, where necessary, of intact LPS, were by [sup1]H-NMR spectroscopy, Smith degradation, chromium trioxide and enzymic degradations, in conjunction with methylation studies supported by fast-atom-bombardment mass spectrometry and linkage analyses by gas chromatography/mass spectrometry. It was concluded on the basis of the following structures, in which each was linked 1→5 to a terminal 3-deoxy-D-manno-octulosonic acid residue, that the core regions with qualitatively similar sugar compositions showed serotypic differences in one or more of their sequences, linkage types, and anomeric configurations: (formula???).The outer regions of each structure carry Neu5Ac residues linked 2→3 to available β-D-Galp residues and show striking similarities with various glycosphingolipids of the ganglioside family. However, Neu5Ac epitopes are not apparently involved in determining serospecificity. [ABSTRACT FROM AUTHOR]

Stalk lodging contributes to significant crop yield losses. Therefore, understanding the biomechanical strength and structural rigidity of grain stalks can contribute to improving stalk lodging resistance in crops. From the structural constituents of the stalk, the rind provides the principal structure, supporting cells against tension and bending loads. In this work, the biomechanical and viscoelastic behavior of the rind from the internodes of two sweet sorghum varieties (Della and REDforGREEN (RG)), grown in two different growing seasons, were evaluated by three-point micro-bending tests using a dynamic mechanical analyzer (DMA). In addition, the chemical composition of rinds and the microfibril angle (MFA) of the cell wall were determined using XRD. The results revealed that the biomechanical behavior of Della varieties was stiffer and more resistant to loads than that of RG varieties. Two features of the rind biomechanical properties, flexural modulus (FM) and flexural strength (FS), showed a significant reduction for RG. Particularly, a reduction in FS of 16–37% and in FM of 22–41% were detected for RG1. Changes in the stalks' rind biomechanical properties were attributed to cell wall components. Total lignin and glucan/cellulose contents were positively correlated with the FM and FS of the rind. Subsequently, an increase in the two cell wall components drove an increase in stiffness. Furthermore, the MFA of the rind was also found to influence the rind strength. [ABSTRACT FROM AUTHOR]

Peas are an underutilized crop that do not require allergen labeling and are rarely genetically modified. Peas contain less protein than soy and vary in protein composition. Because peas contain more starch than soy and less lipids, an alternative procedure for pea tofu production needs to be developed to prevent excessive starch gelatinization while promoting curd development. To accomplish this, a response surface model design was utilized to determine optimal oil addition, cook time, and salt concentration. Treatment ranges were from 0.0% to 4.2% for oil addition, 60–134 min for cook time, and 5.0%–9.2% for MgCl2 addition. Treatments had varying effects on tofu texture. Cook time was directly proportional to the hardness and could be used to match the soft, firm, and extra firm texture targets of conventional soy tofu. Protein secondary structure was not related to gel strength, indicating a system with synergies between multiple components other than protein. This research will help satisfy the growing demand for alternatives to soy‐based foods. [ABSTRACT FROM AUTHOR]

Tofu, made by coagulating soy milk, is a nutritious food originating in China and is widely consumed globally. Due to allergenicity and consumer perceptions of genetically modified organisms, consumer demand for soy alternatives is increasing. In this study, tofu was made from yellow split peas (Pisum sativum). Effects of pasteurization, fat addition, and curd disruption followed by repressing were studied. Here, disruption was not a chemical disruption, rather a physical disruption of protein curds. Pasteurization alone led to increased uptake of water and nonviable tofus. Disrupted samples became firmer with pasteurization. Texture profile analysis indicated that disruption followed by pasteurization improved hardness from approximately 175 g force from the control, to approximately 325 g force for disrupted + pasteurizated samples without fat addition. A similar trend was observed for samples with fat added, where hardness increased from approximately 50 g force to approximately 75 g force. Fourier‐transform infrared spectroscopy of the amide I region showed that an increase of β‐sheet structures led to increased hardness. The shifts in β‐sheet structures followed the same trends as surface hydrophobicity. Surface hydrophobicity decreased with pasteurization and increased with disruption. Molecular weight analysis showed that shear (from disruption) and heat separately degraded the proteins into smaller polypeptides exposing hydrophobic interiors. Changes to biochemical parameters, such as protein secondary structure and exposure of protein hydrophobic regions, allowed for tofu to be made from yellow field peas. Practical Application: This study provides critical information and a means to produce pea‐based soy‐free tofu. [ABSTRACT FROM AUTHOR]

Biomass and its interactions for heat generation have received little attention. In this study, the woody biomass materials were Prosopis africana (PA), Harungana madascariences (HM), Vitrllaria paradoxa (VP), and Afzelia africana (AA). The composition (extractives, carbohydrate, and lignin) of the biomass was determined. The biomass was converted to charcoal in a traditional kiln. A thermo-kinetic examination of the charcoal samples was carried out. The kinetic parameters and potential reaction mechanisms involved in the decomposition process were both obtained using the integral (Flynn–Wall Ozawa) isoconversional methods in conjunction with the Coats-Redfern approach. The activation energy profiles for the charcoal samples in oxidizing atmospheres were 548 kJ/mol for AA, 274 kJ/mol for VP, 548 kJ/mol for PA, and 274 kJ/mol for HM. All charcoal samples underwent comprehensive, multi-step, complex reaction pathways for thermal degradation. The charcoal samples exhibit not only great potential for biochemical extraction but also for bioenergy applications. The significant amount of combustion characteristics in the raw biomass and charcoal samples indicates that each type of wood charcoal produced has more fixed carbon, less ash, and less volatile matter, all of which are desirable for the thermo-chemical conversion of biomass for the production of heat. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Grown field cultured algae that was fed with diary manure waste water. • Compared field cultured to food grade commercial algae by their chemical and thermal properties. • Bio-oil, biochar and gas products were produced by pyrolysis and yields were temperature dependent. • Pyrolysis bio-oil mainly contained lipid derived compounds. Abstract Chlorella vulgaris algae is comprised of a complex mixture of compounds such as carbohydrates, lipids, and proteins and is a suitable feedstock for biofuels. The aim of this study was to convert commercial and a low cost field cultivated algae, via pyrolysis, to produce bio-oil, synthesis gas, and biochar products. The thermal degradation behaviour of algae was investigated by thermogravimetric analysis. Proximate, ultimate, fatty acid methyl ester and carbohydrates analyses, and pyrolysis–GCMS were further employed to characterize the chemical components of algae. Commercial and field cultured C. vulgaris algae was pyrolyzed (450, 500, and 550 °C) and their pyrolysis products were collected and characterized. The highest biochar yield was 42% at 450 °C and the highest bio-oil yield was 47.7% at 550 °C. The biochar physical and chemical properties were assessed using proximate and ultimate analysis, calorific value, specific surface area, butane absorption activity, Raman spectroscopy, and electron microscopy. Algae biochar was found to be mostly composed of condensed phenolic compounds and majorly disordered amorphous carbon. The bio-oils were characterized by the combination of GC–MS, high-pressure liquid chromatography, and electrospray ionization mass spectrometry. Fatty acids, carbohydrates, nitrogen-containing compounds, and aromatic hydrocarbons were abundantly found in the algae bio-oil. [ABSTRACT FROM AUTHOR]

Brewer’s spent grains, major by-products of the beverage industries, were obtained from a Nigerian brewery and subjected to pyrolysis at 500 °C. Analytical pyrolysis (Py-GC/MS) was conducted on the original BSG, extractive-free BSG and BSG CH 2 Cl 2 extract. There was a marked difference in the concentration of levoglucosan between the extractive-free BSG (40.5%) and the original BSG (11.5%). The Py-GC/MS detected significant amount of palmitic and oleic acids in the three samples. Prior to pyrolysis, the extractives content were isolated through methanolysis, transesterified and subjected to GC/MS analysis. The analysis revealed the presence of linoleic, oleic and palmitic acids in an appreciable quantity. The BSG and its biochar were also characterised according to Fourier transform infrared and Raman spectroscopic, and thermogravimetric analyses alongside some conventional physico-chemical analysis. The total crystallinity and condensation indices were evaluated from specific FTIR spectra peaks so as to monitor structural transformations in the bio-char. Kinetic data were deduced from TGA measurements and it was apparent that thermal decomposition of BSG is better modelled as a multi-step reaction mechanism. The nitrogen content of the bio-char was relatively high making it a suitable feedstock for the production of in situ nitrogenised activated bio-carbon. There was a significant variation between the structural configuration of the original BSG and the bio-char as revealed by the change in the value of the condensation index as well as the cellulose crystallinity content. It may thus be concluded that the BSG biomass would be a viable feedstock for thermal decomposition and other valorisation processes. [ABSTRACT FROM AUTHOR]

Despite its massive potential, Raman imaging represents just a modest fraction of all research and clinical microscopy to date. This is due to the ultralow Raman scattering cross-sections of most biomolecules that impose low-light or photon-sparse conditions. Bioimaging under such conditions is suboptimal, as it either results in ultralow frame rates or requires increased levels of irradiance. Here, we overcome this tradeoff by introducing Raman imaging that operates at both video rates and 1,000-fold lower irradiance than state-of-the-art methods. To accomplish this, we deployed a judicially designed Airy light-sheet microscope to efficiently image large specimen regions. Further, we implemented subphoton per pixel image acquisition and reconstruction to confront issues arising from photon sparsity at just millisecond integrations. We demonstrate the versatility of our approach by imaging a variety of samples, including the three-dimensional (3D) metabolic activity of single microbial cells and the underlying cell-to-cell variability. To image such small-scale targets, we again harnessed photon sparsity to increase magnification without a field-of-view penalty, thus, overcoming another key limitation in modern light-sheet microscopy [ABSTRACT FROM AUTHOR]

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with various 3-hydroxyvalerate (3HV) contents biosynthesized by mixed microbial consortia (MMC) fed fermented dairy manure at the large-scale level was assessed over a 3-month period. The thermal, mechanical, and rheological behavior and the chemical structure of the extracted PHBV biopolymers were studied. The recovery of crude PHBV extracted in a large Soxhlet extractor with CHCl3 for 24 h ranged between 20.6% to 31.8% and purified to yield between 8.9% to 26.9% all based on original biomass. 13C-NMR spectroscopy revealed that the extracted PHBVs have a random distribution of 3HV and 3-hydroxybutyrate (3HB) units and with 3HV content between 16% and 24%. The glass transition temperature (Tg) of the extracted PHBVs varied between −0.7 and −7.4 °C. Some of the extracted PHBVs showed two melting temperatures (Tm) which the lower Tm1 ranged between 126.1 °C and 159.7 °C and the higher Tm2 varied between 152.1 °C and 170.1 °C. The weight average molar mass of extracted PHBVs was wide ranging from 6.49 × 105 g·mol−1 to 28.0 × 105 g·mol−1. The flexural and tensile properties were also determined. The extracted polymers showed a reverse relationship between the 3HV content and Young's modulus, tensile strength, flexural modulus, and flexural strength properties. [ABSTRACT FROM AUTHOR]

Nickel (Ni) and ruthenium (Ru) decorated nanosprings (Ni-NS and Ru-NS) were prepared for use as potential hydrodeoxygenation (HDO) catalysts. The nanocatalysts were characterized by BET surface area measurements, electron microscopy and X-ray diffraction (XRD) and showed the NSs had a helical and mesoporous structure. The Ni and Ru decorated NSs showed good metal dispersity at the NS surface. Catalytic HDO conversion of phenol (model bio-oil compound) using NS were compared to conventional alumina (Al 2 O 3 ) and silica (SiO 2 ) gel catalyst supports. Ni–Al 2 O 3 was easily deactivated in the presence of water while the Ni-NS catalysts performed very well irrespective of water being present. An increase in Ni loading (up to 50%) increased the Ni-NS activity while the high loading resulted in a detrimental effect on the activity of silica gel based catalysts. Ru based catalysts showed better activity and conversion on phenol HDO than Ni based catalysts, even in the presence of water. Ponderosa pine pyrolysis bio-oil was fractionated into water-soluble (WS) and water-insoluble (WI) fractions. The bio-oil WI fraction was first hydrocracked to lower its molar mass and then HDO treated with Ni-NS to successfully form cycloalkanes products. These NS based HDO catalysts show promise for upgrading pyrolysis bio-oils to biofuels. [ABSTRACT FROM AUTHOR]

Polyhydroxybutyrate (PHB) is a bioplastic biosynthesized by microorganisms as an intracellular granule. In this study, PHB was produced by a mixed microbial culture fed crude glycerol in a sequencing batch bioreactor. Bioreactor operations were monitored by near infrared (NIR) spectroscopy (908–1708 nm) with a direct insertion probe to develop a model for predicting microbial PHB concentration. Multivariate statistical methods, principal component analysis (PCA) and partial least squares (PLS), were applied for modeling of the NIR spectral data. The results showed that NIR spectra can (i) be used to predict PHB content in-situ, with a calibration model and prediction model exhibiting a good fit (R 2 = 0.88 and R 2 = 0.89, respectively) and (ii) also be used to monitor substrate, glycerol, concentration. [ABSTRACT FROM AUTHOR]

Stalk lodging (mechanical failure of stalks or stems before harvest) is a major problem in grain production that significantly reduces yield. Efforts to improve stalk lodging are hampered by a limited understanding of the determinants of stalk failure. This study examined the structural bending properties and material bending properties of maize (Zea mays L.) stalks. First, an in-field phenotyping device known as DARLING (Device for Assessing Resistance to Lodging In Grains) was used to determine structural properties of maize stalks. Stalks were then subjected to a rind penetration protocol and morphological measurements were acquired. Finally, small strips of rind tissue were excised from the stalks and micro three-point bending tests were conducted to determine the material properties of the rind tissue. Results showed that the material bending strength of the rind tissue was approximately twice as large as the bending stresses present in the rind tissue when failure occurred during field testing. This indicates that stalks ultimately fail due to some form of buckling (i.e., structural failure) as opposed to material failure. This result is relevant to genetic and breeding studies seeking to address the problem of stalk lodging. In particular, these results suggest that improvements in stalk lodging resistance should focus on the stalk's geometric features, such as the ratio of rind thickness to diameter, rather than solely on enhancing material strength. For the samples in this study, material strength ranged between 64 and 197 MPa whereas material stiffness ranged between 4 and 12 GPa. Rind penetration resistance was found to be a good predictor of material properties but a poor predictor of structural properties. • Structural and material bending properties measured for each maize stalk. • Material strength of the rind was twice as large as the structural stress at failure. • Maize stalks lodged due to local buckling (structural failure) not material failure. • Geometrical properties primarily influenced stalk bending strength. • Rind penetration resistance was a poor predictor of structural bending properties. [ABSTRACT FROM AUTHOR]

Plastic waste accumulation has been growing due to the increase in plastic generation and the lack of infrastructure for recycling. One of the approaches is to treat the mixed plastic waste (MPW) through thermal processes to produce feedstocks for other applications. However, the presence of polyvinyl chloride (PVC) in MPW would produce HCl during processing and has negative impacts (emission, catalyst poisoning, etc.). In addition, due to the high heterogeneity of MPW, it is difficult to generate consistent experimental data. In this study, MPW was homogenized through double compounding–extrusion and then formed into a sheet to be treated at 400 °C. The solid products at various mass losses were characterized by heat and chlorine content, Fourier-transform infrared (FTIR) spectroscopy, and elemental composition analysis. It was found that the thermal degradation of MPW started at ~260 °C. The chlorine removal efficiency increased with mass loss and reached an asymptotic value of ~84% at ~28% mass loss, and the remaining chlorine can be attributed to inorganic sources. A PVC de-chlorination model was developed for MPW using TGA data for PVC and MPW to determine organic chlorine removal efficiency. These results show that PVC de-chlorination was not affected by other plastics at this temperature. As the mass loss increases, the heat content first increases and then decreases. It was found that mass loss is a universal parameter for organic chlorine removal efficiency and heat content. The elemental composition analysis and FTIR spectroscopy also shed more light into the chemical changes during MPW thermal degradation. [ABSTRACT FROM AUTHOR]

Torrefaction experiments were carried out on some Nigerian woody ( Albizia pedicellaris (AP), Tectona grandis (TK), Terminalia ivorensis (TI)) and non-woody ( Sorghum bicolour glume (SBG) and stalk (SBS)) biomass resources. The influence of process conditions and consequent change in the elemental configuration of the biomass samples were observed. Biomass type played a dominant role in the solid yield recording 71% for woody and 58% for non-woody samples at 270 °C, while temperature showed the greatest influence with solid yield dropping from an average of 80% (at 240 °C) to 50% (at 300 °C). Both volatile matter and fixed carbon contents experienced significant changes after torrefaction and a decline in O/C ratio from 0.6 to 0.3 was noted. Among the woody biomass, TI experienced the highest increase in higher heating value (HHV) of approximately 38% as compared to AP (32%) and TK (32%), and was subsequently selected for decomposition kinetic study. The decomposition kinetics showed that activation energy ( E ( α )) for the hemicellulose degradation stage ranged between 137 and 197 kJ mol −1 for conversion ( α ) between 0.1 and 0.24 implying that biomass kinetics within this decomposition region is a multi-step reaction. The GC/MS analytical technique revealed that the presence of levoglucosan was highest (7.1%) in woody biomass, while phenolic compounds made up more than one-third of the group of compounds identified. [ABSTRACT FROM AUTHOR]

A non-isothermal decomposition of Moringa oleifera husk and Delonix regia seed pod was carried out in an N2 pyrolytic condition with the primary objective of undertaking the kinetics modeling, thermodynamics and thermal performance analyses of the identified samples. Three different isoconversional models, namely, differential Friedman, Flynn–Wall–Ozawa, and Starink techniques were utilized for the deduction of the kinetics data. The thermodynamic parameters were deduced from the kinetic data based on a first-order chemical reaction model. In the kinetics study, a strong correlation (R2 > 0.9) was observed throughout the conversion range for all the kinetic models. The activation energy profiles showed two distinctive regions. In the first region, the average activation energy values were relatively higher—a typical example is in the Flynn–Wall–Ozawa technique—MH (199 kJ/mol) and RP (194 kJ/mol), while in the second region, MH (292 kJ/mol) and RP (234 kJ/mol). It was also demonstrated that the thermal process for the samples experienced endothermic reactions thought the conversion range. In summary, both the kinetic and thermodynamic parameters vary significantly with conversion—underscoring the complexity associated with the thermal conversion of lignocellulosic biomass samples. [ABSTRACT FROM AUTHOR]

Few multinational companies worldwide can claim to be able to equal the communicative power of Coca-Cola: every advertising and marketing device conceived by the drinks company is a masterpiece of brand image construction and promotion, and of course of corporate storytelling. One of the purposes of corporate storytelling is indeed to build consumer loyalty through brand reputation in order to implicitly reinforce people's opinions about corporate values; considering sustainability, for example, many companies are now including environmental concerns in their promotional strategies. Coca-Cola's most recent advertising campaign, Open Like Never Before, provides an excellent yet controversial example of emotional storytelling. This paper aims to observe the characteristics of Coca Cola's strategies from the theoretical/methodological frameworks of multimodal critical discourse analysis and ecolinguistics - the "ecological analysis of discourse" (Alexander/Stibbe 2014: 104). Drawing also from other disciplines such as social semiotics, and from theories of emotional capitalism, the present study considers both verbal and visual elements to the purpose of deconstructing the sophisticated storytelling techniques employed by Coca-Cola in the Open Like Never Before advertisement. By examining corporate reports and communications via official website and social media, the company's actual commitment to change and sustainability will also be examined so as to yield further relevant information. Ultimately, the discrepancies between the core message of positive change and the negative performances of sustainability reported by the company will be outlined, thus vouching for a multitude of intertwining research perspectives. [ABSTRACT FROM AUTHOR]

• Successful extrusion of torrefied paper-plastic waste blends. • Extrusion of torrefied waste blend reduced variability by a factor of 7. • The plastic layer formed around the extruded fiber prevents water absorption. • The extent of torrefaction influences the combustion properties. With the continued growing U.S. population, solid waste generation will increase, which will lead to undesired and significant growth in landfilling. Thermal treatment can turn these high calorific value wastes into fuels that can be used in small-to-large power plants. This article focuses on using blends with 40% plastic and 60% fiber wastes and converting them into densified solid fuel by torrefaction and extrusion. The material was torrefied at 300 °C to obtain torrefied samples with different mass losses, ranging from 0% to a maximum of 51%. The torrefaction results showed a clear synergy between plastics and fibers. The torrefied material was then extruded into 9 mm diameter rods and the products were characterized by molecular functional group analysis, thermomechanical analysis, dynamic mechanical analysis, dynamic rheological measurement, density measurement, flexural testing, water absorption test, size distribution measurement, heat content test, and combustion test. The fiber content in the material decreased as mass loss increased, and the process reduced significantly the variability of the material. The heat content increased as the mass loss increased. The plastic in the feedstock acted as a process enabler as it imparted properties like bindability, water resistance, high heat content, and increased degradation reaction rate. [ABSTRACT FROM AUTHOR]