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Full-Text Articles in Chemistry

Soil Acidity In The Eastern Wheatbelt, W M. Porter, I. R. Wilson Jan 1984

Soil Acidity In The Eastern Wheatbelt, W M. Porter, I. R. Wilson

Journal of the Department of Agriculture, Western Australia, Series 4

In Western Australia parts of the sandplain of the eastern wheatbelt are very acid and produce poor crops, It was not until the late 1970s that the effect of soil acidity on the productivity of the sandplain soils was examined in any detail.

Since then researchers have learnt a great deal about the nature of soil acidity in the eastern wheatbelt sandplain soils and can suggest management options for farmers.

This article discisses the problem of the very acid soils. It does not deal with the moderately acid, medium textured soils of the eastern wheatbelt. Although the acidity of these …


Soil Acidity And Liming In The Lower Great Southern, R N. Glencross, M. G. Clarke Jan 1984

Soil Acidity And Liming In The Lower Great Southern, R N. Glencross, M. G. Clarke

Journal of the Department of Agriculture, Western Australia, Series 4

In the 375 to 750 millimetre rainfall area of the Lower Great Southern, reports of loss of subterranean clover from established pastures, reduced carrying capacity for sheep and increasing soil acidity lead to the establishment in 1981 of a research programme into the effects of soil acidity on pasture productivity in that region.


Comparison Of Three Methods For Sampling Fishes And Macroinvertebrates In A Vegetated Wetland, B. J. Freeman, H. S. Greening, J. Douglas Oliver Jan 1984

Comparison Of Three Methods For Sampling Fishes And Macroinvertebrates In A Vegetated Wetland, B. J. Freeman, H. S. Greening, J. Douglas Oliver

Faculty Publications and Presentations

Three methods of sampling fishes, two seining methods and a drop trap method, were evaluated in heavily vegetated freshwater habitats. The portable drop trap method, which utilized a 1 x 1 m-sq. trap, collected significantly more macroinvertebrates and fish per unit area than did the seining methods. The meter square drop trap offered the additional advantages of a greater number of animals per unit effort and an integrated sample of vegetation, macroinvertebrates and fish in a given area. A 90% (s.d.= 7.4%) recovery of tagged fishes released into the traps in different habitats showed the m2 drop trap to be …


Sulphur Needs Of Crops And Pastures, J S. Yeates Jan 1984

Sulphur Needs Of Crops And Pastures, J S. Yeates

Journal of the Department of Agriculture, Western Australia, Series 4

Sulphur deficiency has long been recognised as a potential problem of legume pastures in the higher rainfall areas (over 750 mm a year) of south-west Western Australia. Before the introduction of granulated superphosphate (about 1970), sulfer deficiencies commonly developed in spring on susceptible soils despite autumn applications of superphosphate (containing about 10.5 per cent sulphur).

In loww and medium rainfall areas sulphur deficiency is rarely reported, at least partly because of annual superphosphate applications. However large areas of the sandy-surfaced soils of Western Australia would become sulphur deficient for pastures and crops if sulphur inputsd in fertilisers were substantially reduced. …


The Synthesis Of Various Substituted 3-Amino-7-Hydroxy-2,2-Dimethyltetralins And Their Opioid-Related Activities, David Alan Lippman Jan 1984

The Synthesis Of Various Substituted 3-Amino-7-Hydroxy-2,2-Dimethyltetralins And Their Opioid-Related Activities, David Alan Lippman

University of the Pacific Theses and Dissertations

A series of aminotetralones and aminotetralins were synthesized from the common intermediate F, 3-amino-2,2-dimethyl-7-methoxy- 1-tetralone. The final compounds derived from F were simple substituted and/or reduced analogues. The products would allow a progressive structure activity relationship to be drawn based on pharmacological testing.

The common intermediate F was synthesized utilizing a six step procedure starting with p-methoxyphenylacetic acid. The overall yield from the precursor to the F:HC1 was 25%. Compound F was either O-demethylated to form 3-amino-2,2-dimethyl-7-hydroxy-l-tetralone (I) or was dimethylated on the amine and subsequently O-demethylated to yield the 3-dimethylamino-7-hydroxy-2,2-dimethyl-l-tetralone (J). The last major modification was the reduction of …


Determination Of N,N'-Diphenylguanidine In Biological Tissues And Fluids Using High Pressure Liquid Chromatography, Edward Sidney Hunter Iii Oct 1983

Determination Of N,N'-Diphenylguanidine In Biological Tissues And Fluids Using High Pressure Liquid Chromatography, Edward Sidney Hunter Iii

Chemistry & Biochemistry Theses & Dissertations

N,N'-Diphenylguanidine (DPG) is a potentially toxic compound used in the vulcanization of rubber products. Distribution of DPG in hybrid mice (C57BL/6J interbred with DAB2) was determined following intraperitoneal injection. Urine, fecal material, whole blood and tissues were collected at various times after administration of DPG and the extracts analyzed for DPG by high pressure liquid chromatography. Recovery of DPG from spiked urine and whole blood exceed 90%, however, the recovery of DPG from spiked tissue samples was approximately 70%.

DPG concentration in whole blood reached a maximum within ten minutes and rapidly decreased through 180 minutes after administration …


The Combined Effect Of Cu And Zn On Selenastrum Capricornutum, Helmer Colonia-Roque May 1983

The Combined Effect Of Cu And Zn On Selenastrum Capricornutum, Helmer Colonia-Roque

Dissertations and Theses

It has been demonstrated that the toxicity of heavy metals depends on their chemical speciation and can be related to their free ion activities, rather than the total metal concentrations. The objective of this study was to determine the effect of combined free ions of zinc and copper on the toxicity to the green alga Selenastrum capricornutum. This alga was grown in a defined medium, under controlled laboratory conditions, with a varying range of zinc and copper concentrations. The growth rate of the alga was inhibited at pZn = 5.93 or at pCu = 7.24. The results suggest that …


Use Of Hydroelectric Dams To Control Evaporation And Salinity In The Colorado River System, Larry J. Paulson Jan 1983

Use Of Hydroelectric Dams To Control Evaporation And Salinity In The Colorado River System, Larry J. Paulson

Publications (WR)

The main stem reservoirs on the Colorado River comprise one of the largest and most heavily used freshwater bodies in the nation. These reservoirs (Lake Powell, Lake Mead, Lake Mohave and Lake Havasu) can store up to 53,590,400 acre-feet of water at their maximum capacities. Nonetheless, local water shortages still exist in some areas of the Colorado River Basin. There is also concern that salt concentrations are approaching levels that could severely affect municipal and agricultural uses. Water shortages will become even more acute as demands for water increase with continued urban and agricultural development in the basin. Water conservation …


Analysis Of The Surface Polysaccharides Of R. Trifolii Su843 And Its Sym Plasmid Alterated Mutants, Jauh-Lin Duh Jan 1983

Analysis Of The Surface Polysaccharides Of R. Trifolii Su843 And Its Sym Plasmid Alterated Mutants, Jauh-Lin Duh

Masters Theses

The Rhizobium trifolii polysaccharides from SU843 and mutants--HC843(pBR1AN), HC843, 8002--in which the sym plasmid is replaced, absent, or mutated by transposon Tn5 were isolated. The surface polysaccharides of genetically altered mutants were compared quantitatively and qualitatively with one another and with the parent strain. The interpretation of these results is discussed in relation to the function of Rhizobium surface polysaccharides in the symbiotic process. The symbiotic ability of SU843 and mutant strains is as follows: (a) SU843, nod+, fix+; (b) mutant 8002, roa+ (still attaches to root hair), hac-, nod-; (c) …


Spermidine-Condensed Phi X174 Dna Cleavage By Micrococcal Nuclease: Torus Cleavage Model And Evidence For Unidirectional Circumferential Dna Wrapping., Kenneth A. Marx, Thomas C. Reynolds Nov 1982

Spermidine-Condensed Phi X174 Dna Cleavage By Micrococcal Nuclease: Torus Cleavage Model And Evidence For Unidirectional Circumferential Dna Wrapping., Kenneth A. Marx, Thomas C. Reynolds

Dartmouth Scholarship

Spermidine-condensed phi X174 replicative form (RF) II DNA was digested with micrococcal nuclease to yield seven identifiable DNA bands forming an arithmetic fragment-length series. The DNA monomer unit length was found to be 780 +/- 80 base pairs. This result is most consistent with a proposed model for micrococcal nuclease cleavage of a DNA torus organized by the unidirectional, circumferential wrapping of B-geometry DNA. By a topological consideration, the blunt-end-rod-fusion model for torus formation [Eickbush, T. H. & Moudrianakis, E. N. (1978) Cell 13, 295-306] is shown to be inconsistent with our empirical solution results. We propose a continuous, circumferential …


Development Of An On-Line Computer System For Enzyme Kinetics Studies, Jacqueline R. Thweatt Jul 1982

Development Of An On-Line Computer System For Enzyme Kinetics Studies, Jacqueline R. Thweatt

Chemistry & Biochemistry Theses & Dissertations

The PDP-11/10 minicomputer was interfaced to the Beckman 25 ultraviolet/visible spectrophotometer and this on-line computer system was applied to enzyme kinetics studies. This interface involved hardware equipment to locate, amplify, and transmit the analog signal to an analog-to-digital converter, and software to acquire and store the digital data. Data processing programs were used to calculate kinetic parameters and statistical information from the acquired data.

The Varian Cary 219 ultraviolet/visible spectrophotometer can be readily interfaced to the Apple II Plus microcomputer by hardware equipment which can be purchased from the manufacturer. Various software may also be purchased for use in enzyme …


Ortho Cyclization Reactions Of Catecholamines, Robert Lee Hudkins Apr 1982

Ortho Cyclization Reactions Of Catecholamines, Robert Lee Hudkins

Chemistry & Biochemistry Theses & Dissertations

A study was undertaken to examine the potential for ortho cyclization associated with the synthesis of 1,2,3,4,-tetrahydroisoquinolines using the Pictet-Spengler reaction. Specif1cally, the condensation of the biogenic amines, dopamine, norepinephrine and epinephrine were carefully examined in light of current literature and the facility and extent of ortho cyclization in each case. The para isomers of these three biogenic amine condensation products were isolated and characterized, while only the ortho isomer derived from dopamine was found stable and could be isolated, and structurally identified. These studies demonstrate that a second cyclization product does, in fact, form in each instance and that …


High-Temperature Battery Calorimeter, L. D. Hansen, R. H. Hart, D. M. Chen, H. F. Gibbard Apr 1982

High-Temperature Battery Calorimeter, L. D. Hansen, R. H. Hart, D. M. Chen, H. F. Gibbard

Faculty Publications

A battery calorimeter was built for the measurement of thermal energy generation of high-temperature lithium–aluminum/iron sulfide battery cells, which are under development for electric vehicle propulsion and other energy storage applications. The calorimeter was designed with a temperature range of 400˚–500˚C, a detection limit of 1 mW, and an upper limit of heat flow of 50 W. The results of measurements on 200-Ah LiAl/FeS cells were in excellent agreement with the predictions of thermodynamic calculations based on precise measurements of the total cell polarization and the temperature coefficient of the emf. Details of the construction and operation principles of this …


Organic N-Chloramines: Chemistry And Toxicology, Frank E. Scully, Jr., Maxwell A. Bempong Jan 1982

Organic N-Chloramines: Chemistry And Toxicology, Frank E. Scully, Jr., Maxwell A. Bempong

Chemistry & Biochemistry Faculty Publications

The stability of aqueous solutions of organic N-chloramines, suspected of contaminating chlorinated water, has been studied. Two factors influence the decomposition of solutions of N-chloropiperidine and N-chlorodiethylamine: a spontaneous decomposition and photodecomposition. Since solutions of these compounds are relatively long-lived, a need for an analytical method for their identification is discussed. A new method is described which involves reaction of organic N-chloramines with arenesulfinic acid salts. The method gives high yields of stable arenesulfonamides. Several toxicological studies of N-chloropiperidine are described. The compound is mutagenic by Ames assay in Salmonella typhimurium strain TA 100 and does not require metabolic activation …


Diagenesis Of Organic Matter In Las Vegas Bay And Bonelli Bay, Lake Mead, James W. Murray, Carolyn J. Jones, Kathy Kuivila, Jeff Sawlan Jul 1981

Diagenesis Of Organic Matter In Las Vegas Bay And Bonelli Bay, Lake Mead, James W. Murray, Carolyn J. Jones, Kathy Kuivila, Jeff Sawlan

Publications (WR)

The interstitial water chemistry of the sediments of Las Vegas Bay and Bonelli Bay in Lake Mead has been studied as part of a comprehensive water quality study of those locations. Pore water and solid phase analyses were completed from four stations in Las Vegas Bay and two stations in Bonelli Bay. At both locations the pore water compositions and organic matter diagenesis in the sediments are dominated by sulfate reduction. This major role of sulfate reduction is unusual for lake sediments and reflects the fact that SO4 is the major anion in the lake water. In addition, gypsum …


The Transport And Intracellular Distribution Of Iron In The Basidiomycete, Ustilago Sphaerogena, Charles W. Passavant May 1981

The Transport And Intracellular Distribution Of Iron In The Basidiomycete, Ustilago Sphaerogena, Charles W. Passavant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The transport and intracellular distribution of iron in Ustilago sphaerogena via the native siderochrome ferrichrome A has been examined. Evidence is presented which suggests the involvement of deferriferrichrome in iron transport when the metal is supplied to the cell as ferrichrome A. This process requires both oxygen and ATP synthesis and may require a transmembrane electrochemical gradient. Once inside the cell, iron derived from ferrichrome A is rapidly distributed, with a major fraction found in the mitochondria, presumably as heme.

The kinetics of ferrichrome and ferrichrome A uptake have also been investigated. The Km of transport of ferrichrome was …


High Performance Liquid Chromatographic Analysis Of Biogenic Amines, Thais Edwina Ahrendt Keegan Apr 1981

High Performance Liquid Chromatographic Analysis Of Biogenic Amines, Thais Edwina Ahrendt Keegan

Chemistry & Biochemistry Theses & Dissertations

The objectives of this research were to develop a sensitive method for separation and quantitation of biogenic amines and to apply that procedure by monitoring neurochemical changes resulting from stimuli to the test system.

Primary aromatic amines were derivatized with o-phthalaldehyde-mercaptoethanol prior to chromatography, Separation of the fluorescent adduct was achieved using a μBondapak/ phenyl reversed-phase column and a two-step gradient of methanol:0.08 M acetic acid, pH J.O. Fluorescence was monitored using a J40 nm excitation energy and an emission filter which transmits radiation greater than 400 nm (50% T at 418 nanometers).

Following optimization of the chromatographic conditions, studies …


Influence Of Las Vegas Wash Density Current On Nutrient Availability And Phytoplankton Growth In Lake Mead, John R. Baker, Larry J. Paulson Jun 1980

Influence Of Las Vegas Wash Density Current On Nutrient Availability And Phytoplankton Growth In Lake Mead, John R. Baker, Larry J. Paulson

Publications (WR)

Density currents are commonly formed in reservoirs because of temperature or salinity induced density differences between inflowing and receiving waters. Anderson and Pritchard (1951) were among the first to demonstrate this in their investigations of density currents in Lake Mead. They found that the Colorado River formed an underflow in Lake Mead during the winter, an overflow in the spring and an interflow in the summer and fall. Wunderlich and Elder (1973) have since described the hydromechanics of these types of flow patterns, and density currents have been reported for several other large reservoirs (Carmack et al. 1979, Johnson and …


Studies Of The Reorientational Relaxation Of Pyridine In Water By Depolarized Rayleigh Light Scattering, C. H. Wang, Scott L. Whittenburg, P. A. Lund, D. H. Christensen Apr 1980

Studies Of The Reorientational Relaxation Of Pyridine In Water By Depolarized Rayleigh Light Scattering, C. H. Wang, Scott L. Whittenburg, P. A. Lund, D. H. Christensen

Chemistry and Biochemistry Faculty Publications

The depolarized Rayleigh spectra of aqueous solutions of pyridine have been studied using a high‐finesse Fabry–Perot interferometer as a function of temperature and concentration. The Rayleigh relaxation times are found to have a complex concentration and viscosity dependence. The classical Stokes–Einstein–Debye equation for molecular reorientation breaks down in this system. The Rayleigh relaxation time of pyridine molecules is not determined by the macroscopic shear viscosity of the solution. The specific interaction due to the formation of hydrogen bonds between pyridine and water molecules plays a very important role in affecting the relaxation time. At a fixed temperature the plot of …


Adaptative Alteration In Phospholipid Composition Of Plasma Membranes From A Somatic Cell Mutant Defective In The Regulation Of Cholesterol Biosynthesis, Michael Sinensky Jan 1980

Adaptative Alteration In Phospholipid Composition Of Plasma Membranes From A Somatic Cell Mutant Defective In The Regulation Of Cholesterol Biosynthesis, Michael Sinensky

Faculty Publications, Biological Sciences

A somatic cell mutant (CR1) of a Chinese hamster ovary cell (CHO-K1) which has previously been shown to be defective in the regulation of cholesterol biosynthesis accumulates more cholesterol than the parental cell line in plasma membranes. Although such an increase in membrane cholesterol should lead to an increase in the order parameter of these membranes, as measured with an electron spin resonance spin probe, the order parameters of mutant and wild-type plasma membranes are identical--apparently because of an adaptive alteration in membrane phospholipid composition. The phospholipid compositions of mutant and wild-type cell plasma membranes are compared and the mutant …


The Association Of 5.8 S With 28s Ribosomal Rna, Nandita Banerjee Jan 1980

The Association Of 5.8 S With 28s Ribosomal Rna, Nandita Banerjee

Chemistry & Biochemistry Theses & Dissertations

5.8S rRNA is a low molecular weight ribosomal RNA which is noncovalently bonded to the larger ribosomal subunit 28S rRNA; through its 3' end and through its 5' end. This interaction is an integral part of the ribosome, and plays an important role in the ribosome structure and function.

There is a high degree of homology between the 5.8S rRNA primary structures of rat, turtle and chicken. The base sequence of rat 5.8S rRNA differs only in one position from that of turtle and in three positions fr.om that of cl1.icken. Tl1ere is a single purine substitution at the 5' …


Heating-Effect Minimization In Dye Lasers, Kenneth Lee Matheson, James M. Thorne Aug 1979

Heating-Effect Minimization In Dye Lasers, Kenneth Lee Matheson, James M. Thorne

Faculty Publications

Optical pumping of dye lasers deposits heat nonuniformly in the active medium. Because the refractive index of a liquid or gas is a function of temperature, gradients are created which refract the laser beam. This effect is sometimes serious enough to quench laser action. In this paper, we evaluate the effects caused by optical pumping with a coaxial flashlamp and suggest ultraviolet absorbers and wavelength shifters as materials for minimizing the problem


Bulletin 3992 - Nitrogenous Fertilisers For Cereal Production, M. G. Mason Apr 1979

Bulletin 3992 - Nitrogenous Fertilisers For Cereal Production, M. G. Mason

Bulletins - 3000 - 3999

Because fertiliser prices continue to rise, it is becoming increasingly important to understand what affects the response to fertilisers by crops.

Among the many factors influencing crop response to nitrogen applications, the most important are the season, soil type, paddock history, time of application and source of nitrogen. Before deciding whether to use nitrogen on a cereal crop, which source to use and at what rate, the farmer needs some understanding of how these factors work.


Pulling The Wool Off, Department Of Agriculture, Western Australia Jan 1979

Pulling The Wool Off, Department Of Agriculture, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

The Department of Agriculture has begun a three year project to study the potential for "chemical shearing" or, more correctly, biological defleecing.


An Emulsion Dye Laser, Kenneth Lee Matheson, James M. Thorne Nov 1978

An Emulsion Dye Laser, Kenneth Lee Matheson, James M. Thorne

Faculty Publications

A laser dye which is insoluble in water has been dissolved in hexane and emulsified in a water matrix. When pumped with a nitrogen laser, this mixture was observed to lase. The emulsion is superior to a simple hexane solution because the excellent thermo-optical properties of the water matrix help prevent refractive-index gradients from degrading laser performance. This is a useful characteristic for flash-pumped dye lasers, laser-pumped dye lasers, and liquid filters. Another type of solvent system, a critical solution, is also discussed. For certain dyes, a critical solution has even better thermo-optical properties because of its ability to absorb …


The Kinetics Of Solvent Reorientation In Hydroxylated Solvents From The Exciting-Wavelength Dependence Of Chromophore Emission Spectra, John Milton, Robert M. Purkey, William C. Galley Jun 1978

The Kinetics Of Solvent Reorientation In Hydroxylated Solvents From The Exciting-Wavelength Dependence Of Chromophore Emission Spectra, John Milton, Robert M. Purkey, William C. Galley

WM Keck Science Faculty Papers

The disappearance of the exciting-wavelength dependence of the phosphorescence spectra of polar, aromatic chromophores in supercooled glycol–water mixtures is utilized to monitor the kinetics of solvent reorientation. Reorientation times in the nanosecond to second range are obtained for (3:2 v/v) glycerol–water and (1:1 v/v) ethylene glycol–water at 140–240 °K. The results suggest that the process is one involving a cluster of solvent molecules and in which the chromophore plays a relatively passive role. Steady-state data and direct measurements of phosphorescence shifts as a function of time indicate that the solvent reorientation process is nonexponential in nature. The decay function derived …


New Header Treatment Aids Weevil Control, J H. Moulden Jan 1978

New Header Treatment Aids Weevil Control, J H. Moulden

Journal of the Department of Agriculture, Western Australia, Series 4

A new insecticide formulation supplied in high pressure cylinders simplifies weevil control in headers.


Light Scattering Studies Of Transverse Sound Wave And Molecular Motion In Benzonitrile, Scott L. Whittenburg, C. H. Wang Jun 1977

Light Scattering Studies Of Transverse Sound Wave And Molecular Motion In Benzonitrile, Scott L. Whittenburg, C. H. Wang

Chemistry and Biochemistry Faculty Publications

The zero‐frequency shear wave dip appearing in the depolarized Rayleigh spectrum in benzonitrile has been studied as a function of concentration and temperature. The solution study was carried out at constant viscosity equal to the viscosity of liquid benzonitrile at each temperature. The result indicates that the presence of shear wave fine structure does not depend on the collective orientational fluctuations. The orientational and vibrational relaxation times of benzonitrile were measured at various concentrations and temperatures. The orientational relaxation times show no concentration dependence at any temperature, suggesting that the pair correlation is negligible at all concentrations. The orientational relaxation …


Light Scattering Studies Of Rotational And Vibrational Relaxations Of Acetonitrile In Carbon Tetrachloride, Scott L. Whittenburg, C. H. Wang May 1977

Light Scattering Studies Of Rotational And Vibrational Relaxations Of Acetonitrile In Carbon Tetrachloride, Scott L. Whittenburg, C. H. Wang

Chemistry and Biochemistry Faculty Publications

The rotational and vibrational relaxation times of acetonitrile–carbon tetrachloride solutions were investigated as a function of concentration, viscosity, and temperature using depolarized Rayleigh and Raman scattering. Using a Fabry‐Perot interferometer and single frequency laser source, we have shown that reliable results for the single particle orientational correlation times (τs) for CH3CN can be obtained by carrying out a concentration dependent depolarized Rayleigh scattering study. Raman scattering was shown to yield inconsistent results for τs in CH3CN. At constant viscosity, it was found that the Rayleigh scatteringrelaxation time (τRay) of CH3 …


Intermolecular Potential Surfaces From Electron Gas Methods. Ii. Angle And Distance Dependence Of The A’ And A” Ar–No(X^2ii) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack Feb 1977

Intermolecular Potential Surfaces From Electron Gas Methods. Ii. Angle And Distance Dependence Of The A’ And A” Ar–No(X^2ii) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack

Faculty Publications

Angle dependent intermolecular potential energy surfaces for the two states (2A’ and 2A”) that arise from the interaction of ground (X^2II) state NO with Ar are calculated using the electron gas model to obtain the short range interactions. The average and difference of the two interaction energies are fit to analytic forms convenient for use in scattering calculations and joined smoothly onto the long range van der Waals potential previously determined. The results, which appear to be of useful accuracy, and the applicability of the electron gas model to such open shell–closed shell interactions are discussed.