Oven drying study

Oven drying study — 30 minutes. (Photograph courtesy of DuPont and Co.)... 

Carbon represents about 50% of the total oven-dried biomass present in forests [32]. Estimation of carbon pools in forests necessarily involves studying the different strata of biomass present in them. In the different studies, the following carbon pools and variables were measured ... 

A more recent study of the effect of drying on various species of phosphate in soil showed that drying had little effect on some species while having a pronounced effect on others [13]. In nature, soil is never heated to the temperatures used in oven drying, and thus the results of analysis of oven-dried soils are not considered representative of the soils natural conditions. 

In any study of the moisture sorption-desorption properties of modified wood, the moisture content of the samples is determined using gravimetric methods. Invariably, the EMC of the sample is based upon the oven-dry weight of the modified wood ... 

The residual content of immiscible liquids can be defined by the amount of NAPL remaining in the subsurface when pore geometry permits NAPL flow greater than the retention capacity. In an outdoor pilot experiment. Fine and Yaron (1993) studied the effect of soil constituents and soil moisture contents on the retention of kerosene in the subsurface. This retention is termed the kerosene residual content (KRC). Ten soils were studied, with a broad spectrum of clay and organic matter contents, together with four soil moisture contents corresponding to oven-dried, air-dried. 

Soil Moisture Effect The effects of soil moisture content and soil texture and pore size distribution on kerosene conductivity were studied by Gerstl et al. (1994). Figure 12.13B shows the kerosene conductivity in sand, loam, and clay soil columns, as the initial moisture content varies from 0% (oven dried) to field capacity. 

In Canada, InterGroup Consulting Economists (O estimated wood procurement costs in 62 forest zones across the country and generated cost data for the 20 zones having sufficient surplus roundwood to sustain a minimum 18,000 tonne per year methanol plant operation, based on a biomass recovery of 30%. The procurement costs shown in Table II represent the delivered chip cost, as in the Battelle study, but include capital and operating costs on an undiscounted cost basis. Unlike the Battelle study, the estimate is based on oven dry wood. The final results are very similar. 

The 55% ethanol extracted 6.91% of the weight of average oven-dry American oak (Table III). In flavoring 1 liter of California port wine for one taster, an average of 575 mg of this wood, 38 mg of its solid, or 13 mg of its phenols extractable by 55% alcohol produced a just detectable difference. A series of five samples of European oak in comparable analyses averaged 11.37% extractable solids, and 1 liter of the same port wine was just detectably flavored by 515 mg of oven-dry wood, 51 mg of extractable solid, or 30 mg of phenol. The fact that European oak contributes more extract and more tannin to wine and yet, per unit of extract or phenol, less flavor is clear from these data. This agrees with tasters opinions and is believed to be because American oak contributes considerably more oak odor per unit of tannin. The amount of flavor per unit of wood is about the same, but the European oak counteracts less flavor per unit of extract by its high extract content. In other tests, 12% alcohol removed 49% as much extract as did 55% alcohol from American oak and 71% as much from French. In earlier tests (47) about 63% as much extract was obtained from American oak by 12% alcohol as by 55% alcohol. Whether these extracts would have the same flavor value has not yet been studied. 

An alternative method was also studied. This involved ratioing the intensity of the 698 cm 1 styrene band to the intensity of the 2921 cm-1 C-H stretching vibration. Since oils and other additives would interfere with this approach they were extracted with acetone. Vacuum oven drying was then necessary to remove all traces of acetone prior to PA analysis. Otherwise the PA spectrum would be that of acetone rather than that of the rubber since the gas phase spectrum of the acetone would overwhelm that of the solid phase rubber. This technique allowed both solution and emulsion SBR to be analysed by a common method. The results can be expressed by a least squares linear regression equation over the range of 5%-40% styrene in SBR. 

Two species, chir (Pinus roxburghii Sargent.) size 7.5 x 2.75 x 1.25 cm3and mango (Mangifera indica Linn.) size 7.5 x 1.25 x 1.25 cm3 were studied to establish different reaction variables. Four replicates were taken for each treatment and experiments were carried out with oven-dried samples except in case of those where effect of moisture content was studied. Samples were placed in a reaction chamber and reaction was carried out under reflux conditions at 93+1 C, the boiling point of thioacetic acid. Experimental set-up for vapor phase acetylation is shown in Figure 1. 

In a number of experiments studying the incorporation of S3504 into seromucoid fractions 10-/il. samples of plasma were applied to paper strips and subjected to electrophoresis in the Beckman-Spinco paper electrophoresis apparatus. The resultant oven-dried paper strips were attached to an 8 x 10 sheet of paper and applied directly to a sheet of Eastman No-screen x-ray film. Exposure extended over a period of 1 month. At the end of this time the film was developed in the usual manner (see Figure 2). The paper strips were then stained with bromophe-nol blue to demonstrate the major protein fractions. 

Yano et al. [53] studied acoustic properties of acetylated Sitka spruce by specific dynamic Young s modulus and by logarithmic decrement. For oven-dried specimens, both the modulus and the decrement have been found to increase. Meanwhile, mechanical properties are generally unchanged and adhesive strength is reduced by acetylation [2]. Furthermore, creep deformation of wood under humidity change is remarkably reduced by acetylation [54]. 

In this section, representative experimental details of the synthesis and photochemical study of the [(Ti -C5H5)Fe(CO)2] (Fp) disilanes and the Fp- and [( T] -C5H5)Fe( T] -C5H4)] (Fc)-substituted polysilanes are presented. All manipulations were performed under dry nitrogen or argon atmosphere in oven-dried glassware with dry solvents. 

Bleached, soda pulp contained about the same amount of resistant xylan as bleached, sulfate pulp, and a bleached, sulfite pulp contained only a small amount (Table X). In this same study," it was observed that the resistant-xylan content was greater in an air-dried or oven-dried pulp than in the same pulp before drying (see Table XI). In agreement with the work of Meller," a reduction in resistant xylan resulted from mechanical beating or grinding. 

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