Effect of Lignin Content and Extractives on the Higher Heating Value of Wood

As part of a study of the charring rate of wood, I determined the higher heating values (gross heat of combustion) and the chemical composition of samples from four hardwoods and four softwoods. The higher heating value of wood was correlated with lignin and extractive contents. There was a highly significant linear correlation between the higher heating value of the extractive-free wood and lignin content. Equations are presented that can be used to determine the higher heating value of extractive-free wood when the Klason lignin content is known. The equations should be useful to those interested in using a variety of species of wood as fuel

Analysis of dimethyl sulfonium compounds in marine algae

A method is described for the quantitation of the dimethyl sulfide which is released from marine algae by treatment with alkali. Results show that this dimethyl sulfide originates from at least two separate pools of dimethyl sulfonium compounds present in the algae...

Hubble Advanced Camera for Surveys Observations of the z=6.42 Quasar SDSS 1148+5251: A Leak in the Gunn-Peterson Trough

The Hubble Advanced Camera for Surveys has been used to obtain a narrow-band image of the weak emission peak seen at lambda=7205 A in the Gunn-Peterson Ly beta absorption trough of the highest redshift quasar, SDSS J1148+5251. The emission looks perfectly point-like; there is no evidence for the intervening galaxy that we previously suggested might be contaminating the quasar spectrum. We derive a more accurate astrometric position for the quasar in the two filters and see no indication of gravitational lensing. We conclude that the light in the Ly beta trough is leaking through two unusually transparent, overlapping windows in the IGM absorption, one in the Ly beta forest at z ~ 6 and one in the Ly alpha forest at z ~ 5. If there are significant optical depth variations on velocity scales small compared with our spectral resolution (~150 km/s), the Ly alpha trough becomes more transparent for a given Ly beta optical depth. Such variations can only strengthen our conclusion that the fraction of neutral hydrogen in the IGM increases dramatically at z>6. We argue that the transmission in the Ly beta trough is not only a more sensitive measure of the neutral fraction than is Ly alpha, it also provides a less biased estimator of the neutral hydrogen fraction than does the Ly alpha transmission.Comment: Submitted to the Astronomical Journa

Clinical validation and cognitive elaboration: signs that encourage sustained recycling

Journal ArticleThree field experiments coupled the clinical psychology concept of validation with Elaboration Likelihood Model-Heuristic-Systematic Model theorizing to increase the influence of persuasive messages on aluminum can recycling. Signs that validated students' complaints that aluminum can recycling was inconvenient, but persuaded them to recycle anyhow (validate-persuade) were expected to reduce reactance, increase scrutiny and cognitive elaboration, and result in longer term behavior change. Across these 3 experiments, signs influenced recycling relative to baseline; a persuasive message was more influential than convenience; and clinical validation received support as a way to increase message scrutiny, cognitive elaboration, and sustained behavior change. [ABSTRACT FROM AUTHOR