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The molecular weights of both the lignosulphonate and carbohydrate fractions leached from sulphite chemimechanical pulps Increased as the leaching proceeded. Lignosulphonate molecular weights rose from 11000 to 61000. Values for the carbohydrate fractions were lower, ranging from 6000 to 17000. For the lignin, the diameter of the equivalent sphere corresponding to the whole sample leached was considerably Higher then the medium-pore diameter of the fiber. This discrepancy Indicated that the lignosulphonate macromolecule in the fiber wall adopted a flat conformation.

Posté sur engrXiv le 13 juin 2021.; The incidence of several respiratory viral infections has been shown to be related to climate. Because humans spend most of their time indoors, measures of indoor climate, rather than outdoor climate, may be better predictors of disease incidence and transmission. Therefore, understanding the relationship between indoor and outdoor climate will help illuminate their influence on the seasonality of diseases caused by respiratory viruses. Indoor-outdoor relationships between temperature and humidity have been documented in temperate regions, but little information is available for tropical regions, where seasonal patterns of respiratory viral diseases differ. We have examined indoor-outdoor correlations of temperature, relative humidity (RH), and absolute humidity (AH) over a 1-year period in each of seven tropical cities. Across all cities, the average monthly indoor temperature was 25±3°C (mean ± standard deviation) with a range of 20–30°C. The average monthly indoor RH was 669% with a range of 50–78%, and the average monthly indoor AH was 153 g/m3 with a range of 10–23 g/m3. Indoor AH and RH were linearly correlated with outdoor AH when the air-conditioning (AC) was off, suggesting that outdoor AH may be a good proxy of indoor humidity in the absence of AC. All indoor measurements were more strongly correlated with outdoor measurements as distance from the equator increased. Such correlations were weaker during the wet season, especially when AC was in operation. These correlations will provide insight for assessing the seasonality of respiratory viral infections using outdoor climate data, which is more widely available than indoor data, even though transmission of these diseases mainly occurs indoors.

International audience; Miscanthus represents a key candidate energy crop for use in biomass-to-liquid fuel-conversion processes and biorefineries to produce a range of liquid fuels and chemicals; it has recently attracted considerable attention. Its yield, elemental composition, carbohydrate and lignin content and composition are of high importance to be reviewed for future biofuel production and development. Starting from Miscanthus, various pre-treatment technologies have recently been developed in the literature to break down the lignin structure, disrupt the crystalline structure of cellulose, and enhance its enzyme digestibility. These technologies included chemical, physicochemical, and biological pre-treatments. Due to its significantly lower concentrations of moisture and ash, Miscanthus also represents a key candidate crop for use in biomass-to-liquid conversion processes to produce a range of liquid fuels and chemicals by thermochemical conversion. The goal of this paper is to review the current status of the technology for biofuel production from this crop within a biorefinery context.

Mulberry wood (Morus alba L.) is traditionally used in Iran to manufacture music instruments such as tar and setar. But little is know and contradictory statements are found on the natural durability of Morus alba. Moreover, in many cases, Iranian instrument makers leave freshly cut Mulberry timber into water (cold or hot) for a time period depending on the craftsman habit, without any real knowledge or rationalization of the process. It is believed that this step induces a better acoustic behaviour of the wood. It also has to be underline that the leaching waters are very aggressive and contribute to severe skin disorders amongst the wood workers. In this study, the natural durability of leached (according to EN84) and un-leached Morus alba was evaluated against both fungi and termites. The fungal tests followed the guidelines of XP Cen/TS 15083-1, and the wood was exposed to temperate and tropical fungal strains. The termite tests were performed according to EN 117 and the mass loss of the samples was measured along with the visual rating. As a second step, wood powder was extracted using different solvents (including water) and preliminary tests on the activity of these extracts on termites were conducted. The chemical analysis of these extractives is still on going.