Location of uronic acid group in Japanese cedar and Japanese beech wood cell walls as evaluated by the influences of minerals on thermal reactivity

The thermal reactivities of cellulose and hemicellulose are significantly different in cell walls when compared with isolated components and differ in Japanese cedar (softwood) and Japanese beech (hardwood). Uronic acid bound to xylan promotes the thermal degradation of cellulose and hemicellulose, and its effect is different depending on the form of free acid (acting as an acid catalyst) or metal uronate (acting as a base catalyst). We evaluated the location of uronic acid in the cell wall by identifying the components affected by demineralization in pyrolysis of cedar and beech wood. The thermal reactivities of xylan and glucomannan in beech were changed by demineralization, but in cedar, glucomannan and cellulose reactivities were changed. Therefore, the location of uronic acid in the cell wall was established and differed between cedar and beech; close to glucomannan and xylan in beech, but close to glucomannan and cellulose in cedar. Such information is important for understanding the ultrastructure and pyrolysis behavior of softwood and hardwood cell walls

Effects of solvent on pyrolysis-assisted catalytic hydrogenolysis of softwood lignin for high-yield production of monomers and phenols, as studied using coniferyl alcohol as a major primary pyrolysis product

Pyrolysis-assisted catalytic hydrogenolysis over Pd/C in anisole (phenyl methyl ether) at relatively high temperatures (>300 °C) can convert softwood lignin into aromatic monomers in >60 mol% yield (based on lignin aromatic rings). In this process, lignin is pyrolytically degraded to soluble intermediates prior to catalytic conversion, therefore the pyrolysis stage plays an important role in determining the yield and monomer composition. In this study, pyrolysis-assisted hydrogenolysis of coniferyl alcohol, which is a major pyrolysis product, and milled wood lignin isolated from Japanese cedar was investigated in various solvents, including water, methanol, toluene, hexane, and anisole, to clarify the solvent effects. The effects of the solvent on undesired side reactions were also explored. The results show that anisole is the best solvent for aromatic monomer production, but hexane is the best solvent for phenol production via demethoxylation. These findings provide insights that will facilitate the development of efficient methods for monomer production from lignin

Effect of process parameters on woody biomass fractionation in a methanol/water mixture in a semi-flow reactor

The degradation of woody biomass in methanol/water mixtures at elevated temperatures and pressures is a promising candidate for chemical production from renewable resources, combining the wood-degrading ability of water with the product-dissolving capacity of methanol. However, the effects of water and methanol on wood degradation remain unclear. In the present study, the effect of process parameters on the degradation of Japanese cedar in methanol/water at 270 ℃ and 10-30 MPa was investigated using a semi-flow reactor in which pressure and temperature can be controlled independently. At 270 ℃, hemicelluloses were degraded and solubilized more preferentially at 10 MPa, but delignification was more preferred at 20 and 30 MPa. In the resulting products, methylation of coniferyl alcohol from lignin and methyl esterification of methyl glucuronopentosan from hemicellulose were more advanced at 20 and 30 MPa than at 10 MPa. These results suggest that at 10 MPa the influence of water is dominant and promotes polysaccharide degradation, whereas at 20 and 30 MPa the influence of methanol is dominant and promotes delignification. Our findings will provide insight into the establishment of efficient chemical production from woody biomass with solvolysis technology

Stable Oligomer Formation from Lignin by Pyrolysis of Softwood in an Aprotic Solvent with a Hydrogen Donor

Pyrolysis of Japanese cedar wood in diphenoxybenzene (an aprotic solvent) with a hydrogen donor was investigated between 270–380 °C. Under these conditions, re-condensation via radical and quinone methide intermediates was efficiently suppressed and a thermally stable oligomer was obtained. The oligomer was stable even after the treatment time was extended. Yields of lignin-derived products at 270 °C were limited to approximately 20 wt %, but increased to >80 wt % (lignin basis) at the higher temperatures. The oligomer yield increased directly with the extent of the cellulose degradation at 350 °C. Based on the NMR analysis results, the ether bonds in lignin were largely cleaved, but condensed linkages such as β-aryl and β-β and 5-5’ types remained. The γ-hydroxypropyl group was identified as a typical side chain, formed by hydrogenation of the double bond of a coniferyl alcohol-type structure

An overview of accessibility measures

This paper presents a review of accessibility measures in transportation studies by addressing its conceptual framework, data requirements, and applications. Depending on the theoretical basis, the accessibility measures are classified, in infrastructure, location, gravity, space-time and utility-based measure. A system approach is applied to identify the relations among the interacting variables: land use, transportation, temporal and individual. The criteria, including theoretical basis, interpretability, and data requirements are used to evaluate these measures. Recent progress in accessibility studies point towards the inclusion of more individual's spatial-temporal accessibility measure (using the space-time prism concept) but the data requirements, and interpretability of this measure remains as a problem. Furthermore, most of the measures for not considering the competition for opportunities (e.g. jobs on the employment market), and it seems to be the main issue for the development of more realistic accessibility measures

Influence of Proteins on the Lignin Decomposition Behavior of Japanese Cedar (Cryptomeria japonica) Wood by Supercritical Methanol Treatment

The effect of adding protein on the decomposition behavior of lignin in Japanese cedar under supercritical methanol conditions (270 °C/27 MPa) was studied. The Klason method was used to detect the lignin content in the insoluble residue following to a 30 min treatment. Adding either an animal (bovine serum albumin) or plant (soy) protein enhanced delignification from 50 to 65% of the lignin-based wt %. This result was attributed to enhanced lignin depolymerization owing to inhibited lignin recondensation and/or the suppressed formation of polysaccharide-derived char via reactions between the protein and polysaccharides. Although the solubilization of lignin was promoted and the yield of lignin-derived low-molecular-weight compounds increased, the selectivity of major monomers such as coniferyl alcohol (CA) and γ-methylated CA decreased. The addition of proteins has a substantial impact on the decomposition behavior of cell wall components under supercritical methanol conditions. This information provides insights into the use of protein-rich lignocelluloses

TiO2-supported Ni-Sn as an effective hydrogenation catalyst for aqueous acetic acid to ethanol

Various Ni and Ni-Sn catalysts supported on TiO2 were prepared and the catalytic activities were evaluated for ethanol formation from aqueous acetic acid. Although catalytic activities of the Ni/TiO2 catalysts were limited, the addition of Sn improved the activity dramatically, and the optimum Ni/Sn ratio was approximately 1:1 (w/w). SnO2, the precursor of Sn, could not be reduced into metal Sn in pure form but did reduce into Ni-Sn alloys in the presence of NiO, the precursor of Ni. Analyses with XRD and SEM-EDS revealed that the Ni-Sn alloys were homogeneously dispersed on the TiO2 surface. Furthermore, IR analysis indicated that the Ti atoms in the catalyst act as a Lewis acid, which coordinates to the oxygen atoms of acetic acid, enhancing the attack of hydrogens activated on neighboring Ni-Sn alloys. Based on these results, Ni-Sn/TiO2 is proposed as an effective hydrogenation catalyst for converting aqueous acetic acid into ethanol

Robot Motion and Grasping for Blindfold Handover

Autonomous robots in human-robot interaction (HRI) recently are becoming part of human life as the number of services or personal robots increasingly used in our home. In order to fulfill the gap of HRI merit, we would like to propose a system of the autonomous robot motion and grasping creation for assisting the disabled person such as the blind people for handover tasks to help blind people in pick and place tasks. In this paper, we develop the robot motion to receive the object by handing over from the blindfold human to represent the blindness. To determine the target of the object and human hand, we implement the 6DOF pose detection using a point cloud and hand detection using the Single Shot Detection model in Deep learning for planning motion using 9DOF arm robot with hand. We finally experiment and evaluate the tasks from blindfold-robot handover tasks

MENSURAÇAO DA UTILIDADE DOS MEIOS DE TRANSPORTES:: UMA ABORDAGEM PSICOFISICA

The objective of this paper is to develop a mathematicalequation that expresses, in terms of cardinal indices, the relative utilities of the means of transportation. We discussed about men's necessities anddesires, men's tendencies of avoiding pain and searching welfare, andalso the utilities perceived by them in ways that can aliviate such anxieties.In the specific case of passenger transportation, in a situation where thetravel is seen as an intermediate activity, we proposed that intrinsical utilityof the means of transportation can be foundamented on the followingprinciple: all of us, independently of our socieconomic situation, seek toabbreviating the time and physical effort spent by transposition of the distancefrom origin to destination. For this reason we propose that relativeutility of each transportation mode be evaluated as a function of these parameters.The literature on Psychophysics and Ergonomics was reviewedsearching ways by which the sensation elicited by a set of physical orsocioeconomic stimuli are usually quantified. We concluded that the travelmode utility index can be obtained through a multiplicative function whosefactors are powers of the following physical stimuli: straight line distancefrom origin to destination, time, and energy spent by time unity.O objetivo deste trabalho é propor uma expressão matemáti­ca que possa traduzir, em termos de índices cardinais, as utilidades rela­tivas dos meios de locomoção. Discorremos sobre necessidades e de­sejos, tendência do homem de afastar-se do sofrimento e de buscar o bem-estar, e também sobre a utilidade que o homem vê nas coisas capa­zes de aliviar essa ansiedade. No caso específico de transporte de pes­soas, na situação onde a viagem é vista como uma atividade intermediá­ria, sugerimos que a utilidade intrínseca dos meios de locomoção seja fundamentada no princípio de que todos nós, independente da nossa si­tuação sócio-econômica, procuramos abreviar o tempo e o esforço físico dispendidos na transposição da distância que separa o destino da origem. Propomos então que a utilidade relativa de um meio de transporte seja estimada em função destas variáveis. Na literatura de psicofísica e ergo­nomia buscamos a maneira como usualmente são quantificadas as sen­sações eliciadas por um conjunto de estímulos físicos ou sócio-econômi-cos. Concluímos que o índice de utilidade de um modo de transporte de passageiros pode ser obtido mediante uso de função multiplicativa cujos fatores são potências dos seguintes estímulos físicos: distância em linha reta entre a origem e o destino da viagem, duração da mesma, e energia média consumida por unidade de tempo