Foliar application of the phytotoxic herbicide diquat dibromide was made to twenty tuliptree seedlings actively growing under field conditions on October 6, 1973, at the Purdue Davis farm in Randolph County, Indiana. Herbicidal extraction was accomplished by two extraction procedures: Langlois, et. al., (1963), and a method described in the Pesticide Analytical Manual (9/1/67). Herbicidal application methods utilized two concentrations and three time periods for translocation to occur.Results from the herbicidal application to the tuliptree seedlings indicate that diquat dibromide is present in all parts of the seedling trees within a two hour time period, and that relative amounts of diquat per plant organ are time dependent.Ball State UniversityMuncie, IN 47306

Klíčová A.: Alkaloids from wood of the species Liriodendron tulipifera L. and their biological activity. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department: Pharmaceutical Botany, Hradec Králové, 2018. Supervisor: PharmDr. Anna Hošťálková, Ph.D. Key words: Liriodendron tulipifera, secondary metabolites, alkaloids, biological activity Alzheimer's disease (AD) is the most common type of dementia. It is neurodegenerative disorder. Patients suffer from cognitive disorder in combination with aphasia, apraxia or disorders of executive functions, which leads to exacerbation of working or social skills. Nowadays, there exist no casual treatment for AD, and that is why the intense research is still waging. Currently there are available remedies, which can slow down progress of AD. These drugs includes also natural substances. An alkaloid extract of Liriodendron tulipifera L. wood showed promising inhibition of human cholinesterases in a preliminary testing. These results were the reason why this extract has been chosen for further isolation of single alkaloids and identification of their biological activity. Isolation was made by column chromatography with step gradient elution. Then was used preparative TLC to isolate single alkaloids. Identification of alkaloids was...

Water and alkali extracted steam exploded yellow poplar fiber (log R₀ 4.25) was purified through a multi-stage process. The initial stage consisted of peralkanoic acid treatment, either formic or acetic acid, at atmospheric pressure. Subsequent bleaching was achieved through treatment with alkaline peroxide in several stages. Performic acid experiments were performed by researchers at the Finnish Pulp and Paper Research Institute: K. Poppius, I. Tuominen and J. Sundquist. Peracetic experiments were conducted at Virginia Tech. The alkanoic acid stage process parameters examined included time (3 and 6 hours primarily), temperature (40 and 60° for the peracetic trials, 80° for the performic trials), acid concentration (25, 50, and 80% for the peracetic trials), and initial peroxide charge (10 and 20 % for the peracetic trials; 2,5, and 10% for the performic trials). The bleached fiber was analyzed on the basis of brightness (diffuse reflectance of hand sheets at 457nm), Kappa number, molecular weight (carbanilation followed by GPC), and carbohydrate composition (complete hydrolysis followed by HPLC). Peroxide concentration was monitored through iodometric titration. The results indicated that the purified fiber may be useful as a microcrystalline cellulose. The purification process occurred in three phases: lignin activation, followed by dissolution, followed by alkaline peroxide bleaching. Brightness correlated well with Kappa number. Molecular weight loss (as weight average) averaged 43%. Glucose purity of 93% was realized for the peracetic trials with residual lignin of approximately 1%. Residual hemicellulose content was approximately 1.5%. Final brightness levels of nearly 90% MgO were attained by the performic acid samples. In terms of percent gain in brightness per percent peroxide consumed, higher temperature resulted in greater efficiency. An alkaline extraction (no peroxide) following the initial acid stage improved efficiency. Initial peracetic peroxide charge of 20% was inefficient compared to an initial charge of 10%. Molecular weight loss was affected by water concentration of the acid stage, but unaffected by an increase in the acid stage temperature from 40° to 60°. Molecular weight loss appeared to increase with acid stage peroxide charge up to 10%, but 20% charge did not result in greater losses. Further research using higher temperatures and a sulfuric acid catalyst are suggested. / Master of Science

This study has been conducted in order to determine whether yellow-poplar (Liriodendron tulipifera Michx.), has the economic and technical potential to be manufactured and marketed as oriented strandboard (OSB) in Elkins, West Virginia and Frederick, Maryland. The estimated annual excess growth of yellow-poplar near Elkins could provide more than enough timber to supply a 120 MMSF OSB facility (3/8-inch basis); however, the estimated annual excess growth of yellow-poplar available near Frederick is insufficient to provide the total wood requirement for a facility of this size. Yellow-poplar is a relatively low density species, and is suitable for the production of OSB. The manufacture of yellow-poplar OSB is viable, employing commercially available technology. OSB is a suitable substitute for softwood plywood sheathing. The panel markets within radii of approximately 300 miles of both Elkins, West Virginia and Frederick, Maryland are sufficient to support the addition of a 120 MMSF OSB facility at either location. Equipment and operating requirements and costs have been estimated for 1982. Using a USDA Forest Service computer program, EVALUE, an internal rate of return on investment (IRR) of 15.2 percent was calculated for Elkins, and 14.3 percent for Frederick. The sensitivity of facility productivity to an increase of 10 percent in the cost of wood, and resin, and to a 10 percent decrease in the price of panels has also been calculated. / M.S.

Wood with a uniform moisture distribution is known to have different mechanical properties compared to wood with a non-uniform moisture distribution. Moisture gradients are likely to develop in full-size members tested in the In-Grade Testing Program and might therefore affect the test results. The purpose of this study was to mathematically model the effect of desorption moisture gradients on the stiffness and strength of yellow-poplar beams. An additional objective was to experimentally determine gradient effects in yellow-poplar beams. Three-dimensional finite-element modeling was employed and several subsidiary models were developed. Among these was a three-parameter segmented model for fitting digitized tension and compression stress-strain curves. Unlike previous models (such as the Ramberg-Osgood model), this model has a linear slope up to the point approximately corresponding to the proportional limit. A methodology was also devised whereby most hardwood and softwood elastic constants can be estimated at any moisture content. Data are required at one moisture content. Equilibrated uniaxial testing was conducted at four moisture contents to acquire data for the finite-element model. It was found that the longitudinal Young's moduli in tension and compression were approximately equal at 6% and 18% moisture content; the compression modulus was greater at 12%, but the tension modulus was greater for green specimens. Intersection points for tension and compression mechanical properties may be different. Tests of small clear yellow-poplar beams indicated that moisture gradients induced at 12% equilibrium moisture content had little effect on the modulus of rupture up to 19% average moisture content. At higher moisture contents, gradient-containing beams were significantly stronger than equilibrated beams when comparisons were made at identical moisture contents. Modulus of elasticity data exhibited a similar trend, although differences between equilibrated and non-equilibrated beams were observed below 19% moisture content. The finite-element program was moderately successful in predicting the effects of moisture gradients on the strength and stiffness of yellow-poplar beams. Computer time and storage constraints limited the accuracy of the solutions. Predicted trends were verified by the experimental data. Modeling of full-size lumber indicated that significant moisture gradients will likely influence the stiffness and strength of higher quality lumber. / Ph. D.

Nine-week-old yellow-poplar and green and white ash were exposed to various concentrations of O₃ (0.00 to 0.15 ppm) and/or SO₂ (0.08 ppm), 4 hr/d, 5d/wk in combination with simulated rain (pHs 5.6, 4.3, 3.0), 1 hr/d, 2 d/wk, for 5 or 6 wk under controlled laboratory conditions. Pollutant exposures resulted in alterations in seedling biomass accumulation, growth rates, changes in carbon allocation among plant parts and modification in physiological processes associated with gas exchange. Ozone (0.010 ppm) and SO₂ together caused a significant decrease in height growth and biomass and an increase in leaf area ratio (LAR) in yellow-poplar. Ozone and SO₂ exposures resulted in linear decreases and increases, respectively, in root dry weight, leaf area increase, relative growth rates of all yellow-poplar plant parts and unit leaf rate with decreasing rain pH. Chlorophyll content increased in both O₃ and SO₂ treatments with increasing rain acidity. In green and white ash experiments height growth was inhibited by O₃, SO₂ and O₃ + SO₂ for green ash, whereas only leaf dry weight was decreased by O₃ exposure in white ash. Decreasing rain pH resulted in linear decreases in root/shoot ratio (RSR) and LAR, for white ash. In green ash, a quadratic response to rain pH occurred with these growth variables. Ozone and O₃ + SO₂-treated green ash exhibited a significant quadratic response in leaf weight ratio with increasing rain acidity. Leaf area ratio and RSR exhibited linear increases and decreases, respectively, for O₃ and rain acidity. In SO₂-treated white ash with increasing white ash and yellow-poplar seedlings exposed to various O₃ concentrations and simulated rain for 5 and 6 weeks, respectively, increasing O₃ concentrations caused linear decreases in height and biomass of white ash. Linear decreases in root growth rate and biomass and RSR occurred with decreasing rain pH, across O₃ treatments. Ozone (0.05 or 0.10 ppm) caused linear decreases in these variables in combination with increasing rain acidity. For yellow-poplar, increasing O₃ concentrations caused linear increases in RSR and specific leaf area. At 0.05 and 0.10 ppm O₃, stem and leaf biomass, their relative growth rates and leaf area all decreased with decreasing rain pH. Ozone (0.10 ppm) exposure caused a decrease in stomatal conductance, and decreasing variable. rain pH resulted in a linear decrease in this A linear decrease in net photosynthesis also occurred with increasing rain acidity in O₃-treated (0.10 ppm) plants. These results demonstrate that gaseous pollutants in combination with simulated acid rain can have detrimental effects on growth of three forest tree species, under controlled laboratory conditions. / Ph. D.

No description available.

Several researchers have concluded that there is little or no relationship between specific gravity and ring width or growth rate in yellow-poplar (Liriodendron tulipifera L.). Because most mechanical properties of wood are also closely related to specific gravity, it would thus be of interest to learn how minimum suppression and maximum release years' evidence that can be extracted from radial growth patterns based on a modified radial growth averaging (RGA) technique's influence the compression parallel to grain strength and specific gravity of wood. This study is designed to evaluate the effects of growth suppression and release on ultimate crushing stress and specific gravity for small-sized yellow-poplar specimens. Additionally, the relationship between specific gravity and ultimate crushing stress is investigated. Twenty-three yellow-poplar cores were examined for their growth ring widths. Minimum suppression and maximum release years were identified based on the modified RGA criteria method. From each increment core, three 1 Ã 1 Ã 4 mm specimens from both minimum suppression and maximum release years were tested for their ultimate crushing stresses using a micro-mechanical test system. The specific gravity of each specimen was also recorded. These data were analyzed using a paired samples t test and a simple linear regression. The results indicate that the mean ultimate crushing stress and specific gravity of maximum release years were significantly higher than that of minimum suppression years. Furthermore, the ultimate crushing stress was linearly related to the specific gravity of the specimens. / Master of Science