Recrystallization behavior of cellulose and lignocellulose from Pinus massoniana

Summary In an X-ray diffraction investigation, the recrystallization behavior of ball-milled Chinese southern pine wood was found to differ from that of cellulose. The crystallinity of lignocellulose milled for a very long time and recrystallized by wetting in water did not decrease with increasing milling time as was the case with milled cellulose. In addition, it appeared that the presence of lignin tended to restrict the amorphous cellulose produced by milling from recrystallizing into Cellulose II, whereas it had no influence on the recrystallization into Cellulose I. These results were discussed in the context of the mechanism of the conversion of Cellulose I to Cellulose II.     

SBELTS: A model of soybean production under tree shelter

Farmers in the North Central region of the United States often are reluctant to use shelterbelts because of inadequate information clearly showing their benefits. We developed a computer model, called SBELTS for ShelterBELT and Soybeans, that simulates the influence of a shelterbelt on soybean (Glycine max L.) production across an agricultural field in the midwestern United States. Objectives of this study were to 1) describe the structure of SBELTS, 2) present model simulations, and 3) discuss model limitations. SBELTS is composed of three submodels. The first submodel produces characteristics of a shelterbelt that are passed to the second submodel that estimates daily windrun at user-specified distances leeward (away from the prevailing wind) of the shelterbelt. Estimated daily windruns are merged with other microclimatic information to produce weather files for each specified distance. Finally, the third submodel uses a soybean growth/yield model to estimate soybean yield at specified distances, and the yields are averaged. Data collection was not a part of the present project, so SBELTS was evaluated by comparing predicted results with published information. SBELTS was used to predict soybean yield across a field leeward of a 7.6 m tall shelterbelt, and the predicted yield curve compared well with published yield curves. The sensitivity of SBELTS to variation in rainfall was evaluated by predicting yields for 3.8 m tall and 7.6 m tall shelterbelts in wet, normal, and dry years. Results showed no shelterbelt influence in wet years, some influence in normal years, and a sizable influence in dry years. Results showed that the 7.6 m shelterbelt had more influence than the 3.8 m shelterbelt. Although SBELTS has limited use, it is the first step in the development of more advanced models that will be able to simulate production of soybeans and other crops under the influence of shelterbelts on a variety of soil types.This revised version was published online in November 2005 with corrections to the Cover Date.     

Armillaramide, a new sphingolipid from the fungus Armillaria mellea.

A new C(18)-phytosphingosine ceramide containing non-hydroxy fatty acid, armillaramide (1), has been isolated together with ergosterol peroxide from the fruiting bodies of the basidiomycete Armillaria mellea. Its structure was established as (2S,3S,4R)-2-hexadecanoylamino-octadecane-1,3,4-triol by spectroscopic and chemical methods.     

Soil properties under a Pinus radiata – ryegrass silvopastoral system in New Zealand. Part II. C and N of soil microbial biomass, and soil N dynamics

At present, our understanding of the dynamics of microbial biomass and soil N in silvopastoral systems is very limited. In this paper, the effects of understorey management on soil microbial C and N, net N mineralization, and net nitrification were studied in two seven-year-old radiata pine (Pinus radiata D. Don) – pasture systems, consisting of plots with and without ryegrass (Lolium perenne) as an understorey. Mini-plots (1 × 1 m) with animals excluded and herbage repeatedly clipped and removed were used for soil sampling. Three mini-plots formed a transect at each of two positions: 0.9 and 3.5 m north of the tree rows. Measurements were taken from July 1997 to June 1998 about once every 40 days. One composite sample was collected from each of two sampling depths (0–10 and 10–20 cm) at each transect position on each sampling date. Temporal and spatial variability of N mineralization rates and microbial biomass C and N was large. Net mineralization and nitrification rates were higher in the bare ground than in the ryegrass plots for a major part of the year, particularly from late spring to early fall. Net N mineralization and nitrification rates were higher in the 0–10 than in the 10–20 cm soil layers in both the ryegrass and bare ground treatments; however, the depth effect on microbial biomass C and N was only significant in the ryegrass treatment. In the surface soil layer, microbial biomass C and N were substantially greater in the ryegrass than in the bare ground plots. Soil microbial properties and activities were closely linked to pasture root activities, soil depth, and site biophysical conditions. This revised version was published online in June 2006 with corrections to the Cover Date.     

Cucubalugenin A, a new triterpenoid from Cucubalus baccifer.

A new triterpenoid, cucubalugenin A (1), has been isolated from the whole plant of Cucubalus baccifer. Its structure was elucidated by spectral methods.     

Application of modal analysis by transfer function to nondestructive testing of wood II: modulus of elasticity evaluation of sections of differing quality in a wooden beam by the curvature of the flexural vibration wave

 The shape of the flexural vibration wave of wooden beams at the first mode was detected using the transfer function. The dynamic modulus of elasticity (MOE) of beam sections of differing quality was estimated from the ratio of the curvature of the wave shape in this section to that of a clear beam. The results were as follows: (1) If a section with a lower dynamic MOE was introduced into a clear wooden beam, the curvature of the wave shape in that section became higher. (2) The ratio of the MOE and the reciprocal of the curvature ratio were highly correlated. (3) The MOE of a defect could be estimated, and the position of the defect could be determined accurately by examining the curvature of the flexural vibration wave shapes. Received: March 22, 2002 / Accepted: May 15, 2002 Part of this report was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April 2000. This article is translated from the Japanese version, which was published in Mokuzai Gakkaishi 47(5), 2001 Correspondence to:Y. Ishimaru     

Consumer willingness to pay price premiums for environmentally certified wood products in the U.S.

Since its inception nearly 15 years ago, environmental certification has become an important issue in the wood products industry. One research question that has been examined is the potential willingness for supply chain participants to pay a premium for certified products or raw materials to offset certification costs. This study examines stated willingness to pay for four wood products from the perspective of U.S. consumers. Data was collected in 1995 and 2005 from the population of U.S. residential consumers to detect changes in willingness to pay for certified wood products along time and increase the statistical strength of the model. Results of an ordered probit model suggest that higher probabilities of paying a premium are associated to consumers who seek out certified products and who believe certification can lessen environmental impacts such as tropical deforestation. There is also a strong relationship between respondent income and willingness-to-pay. Despite the current industry structure in the U.S. that has adopted a mass-certification strategy that does not place price premiums on certified products, results suggest that such premiums may exist for imported certified tropical wood products. Analysis of marginal effects suggests consumers' willingness to pay a 10% premium for three of the four certified items studied. Niche markets may potentially be exploited in the U.S. and price premiums captured by wood products manufacturers in tropical regions and/or American importers.