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Articles 31741 - 31770 of 34607

Full-Text Articles in Physical Sciences and Mathematics

Effect Of Nitrogen Rates On The Copper Concentration, Dry Matter Production And Grain Yield Of Wheat Grown On A Residual Copper Trial., R F. Brennan Jan 1987

Effect Of Nitrogen Rates On The Copper Concentration, Dry Matter Production And Grain Yield Of Wheat Grown On A Residual Copper Trial., R F. Brennan

Experimental Summaries - Plant Research

Trial 67E8

Location: Esperance Downs Research Station.

The trial was originally designed to measure the residual effectiveness of rates of copper sulphate drilled in 1967.


Deep Placement Of Manganese For Lupins, R F. Brennan Jan 1987

Deep Placement Of Manganese For Lupins, R F. Brennan

Experimental Summaries - Plant Research

Trial 87E44

Location: Esperance Downs Research Station

To determine the effect of deep placement of manganese and foliar applied manganese on lupin plant tissue levels, split seed incidence and grain yield.
.


Matricaria/Globe Chamomile (Pentzia Globifera) Density And Seed Production, J. Dodd Jan 1987

Matricaria/Globe Chamomile (Pentzia Globifera) Density And Seed Production, J. Dodd

Experimental Summaries - Plant Research

Location: Muckinbudin.

Preliminary measurement of plant density and seed production were made in November 1987 at two infested properties near Muckinbudin.


Vermin fence herbicide trials (Established by J. R. Peirce 85ME63, 65, 68, 69, 70)


During assessment of the vermin fence herbicide trials in November 1987, certain plants in the sprayed plots were noted as being undamaged, even by the highest rates of herbicides used.


Trace Element Nutrition. Tissue Testing Programme 1987, R. F. Brennan Jan 1987

Trace Element Nutrition. Tissue Testing Programme 1987, R. F. Brennan

Experimental Summaries - Plant Research

Project title: Evaluation of existing diagnostic procedures for the recommendation of trace element fertilizers.

Aim: To compare the accuracy and reliability of a range of tissue and soil tests being variously promoted for use to farmers for the diagnosis and prognosis of zinc and copper deficiencies in wheat crops on Western Australian farms.

Trial 87N23

Nitrogen rates on the main copper plots of the long term copper residual trial at Newdegate Research Station.

Location: Newdegate Research Station

To determine the effects of rates of nitrogen on the copper status of plants.

Trial 87LG33

Effects of rates of nitrogen on the …


The Aperiodic Crystal Picture And Free Energy Barriers In Glasses, Randall W. Hall, Peter G. Wolynes Jan 1987

The Aperiodic Crystal Picture And Free Energy Barriers In Glasses, Randall W. Hall, Peter G. Wolynes

Collected Faculty and Staff Scholarship

The aperiodic crystal picture associates the glass transition with freezing into a nonperiodic structure. Dynamics in the glassy state involves activated jumps between different aperiodic free energy minima. Activation barriers may be estimated through the use of freezing theory and the theory of dense solids. The results resemble, but are distinct from, free volume theory. Reasonable fits to experimental data are obtained.


The Further Geometry Of Grain Boundaries In Hexagonal Close-Packed Metals, Fu-Rong Chen, Alexander H. King Jan 1987

The Further Geometry Of Grain Boundaries In Hexagonal Close-Packed Metals, Fu-Rong Chen, Alexander H. King

Alexander H. King

A technique is given for finding partial DSC vectors appropriate to crystals with more than one atom per lattice site. The DSC lattice is made up of vectors that represent displacements of one crystal with respect to the other that leave the boundary structure shifted, but not complete. A new, rapid method for finding the step vectors associated with perfect DSC dislocations is described. Partial DSC vectors and step vectors for perfect DSC dislocations in hexagonal close-packed crystals are determined. The availability of reactions between lattice partial dislocations and grain boundaries in hexagonal close-packed crystals is also assessed.


Esr Study Of Optically Induced Phase Transitions, Juana Vivó Acrivos, H. P. Hughes, S. S.P. Parkin Jan 1987

Esr Study Of Optically Induced Phase Transitions, Juana Vivó Acrivos, H. P. Hughes, S. S.P. Parkin

Faculty Publications, Chemistry

We have identified an optically enhanced magnetic phase transition in the newly synthesized organic molecular charge transfer salt, (BEDT-TTF)3Ta2F11 (BEDT-TTF bisethylenedithiolotetrathiafulvalene) by ESR absorption measurements in the X band microwave region. At room temperature, only a doublet state ESR absorption is observed, but below 30 K severa~ tripl~t E.SR absorpti_ons appear. The orientation dependence of the ESR absorption under lllummat10n at energies near the band gaps in the material ( 640 nm, T = 12 to 5 K H0 < 0.34 T) indicates that there are rapid spin exchange processes with times r < w-s; near 7 ~o 5 K.along cert~in ~rystallographic directions with a temperature dependen~e suggesting spm-lattlce relaxation times which proceed via Van Vleck "direct processes." This, to our knowledge, is the first case where the magnetic properties of a charge transfer salt are altered by the interaction with photons of energy equal to the band gaps in a low dimensional solid providing a new, interesting way to investigate these materials.


A New Science, And A New Profession: Sugar Chemistry In Louisiana, 1885-1895, John Alfred Heitmann Jan 1987

A New Science, And A New Profession: Sugar Chemistry In Louisiana, 1885-1895, John Alfred Heitmann

History Faculty Publications

Between 1885 and 1895 the Louisiana sugar industry experienced a scientific and technological revolution in methods, process apparatus, and scale of operations. The animal-powered mills and open kettles characteristic of the antebellum period were supplanted by large, technically designed, and scientifically controlled central factories . In 1880 there were approximately 1,000 sugar houses in Louisiana with an average annual production of 110 long tons of sugar per house. By 1900 fewer than 300 factories constituted the state's sugar industry, but yearly production averaged over 980 long tons for each sugar house. One commentator of the period, Mark Twain, described a …


Esr Study Of Optically Induced Phase Transitions, Juana Vivó Acrivos, H. P. Hughes, S. S.P. Parkin Jan 1987

Esr Study Of Optically Induced Phase Transitions, Juana Vivó Acrivos, H. P. Hughes, S. S.P. Parkin

Juana Vivó Acrivos

We have identified an optically enhanced magnetic phase transition in the newly synthesized organic molecular charge transfer salt, (BEDT-TTF)3Ta2F11 (BEDT-TTF bisethylenedithiolotetrathiafulvalene) by ESR absorption measurements in the X band microwave region. At room temperature, only a doublet state ESR absorption is observed, but below 30 K severa~ tripl~t E.SR absorpti_ons appear. The orientation dependence of the ESR absorption under lllummat10n at energies near the band gaps in the material ( 640 nm, T = 12 to 5 K H0 < 0.34 T) indicates that there are rapid spin exchange processes with times r < w-s; near 7 ~o 5 K.along cert~in ~rystallographic directions with a temperature dependen~e suggesting spm-lattlce relaxation times which proceed via Van Vleck "direct processes." This, to our knowledge, is the first case where the magnetic properties of a charge transfer salt are altered by the interaction with photons of energy equal to the band gaps in a low dimensional solid providing a new, interesting way to investigate these materials.


A Theoretical Investigation Of Some Low-Lying Singlet States Of 1,3-Butadiene, Robert J. Cave, Ernest R. Davidson Jan 1987

A Theoretical Investigation Of Some Low-Lying Singlet States Of 1,3-Butadiene, Robert J. Cave, Ernest R. Davidson

All HMC Faculty Publications and Research

Results are presented from extensive ab initio calculations on several low-lying singlet states of cis- and trans-1,3-butadiene. The results indicate a qualitative difference between the cis and trans isomers for the lowest π → π* transition. For the cis isomer, the first excited singlet state of the same symmetry as the ground state is found to lie above the lowest π → π* transition, and we estimate that this is also the case for the trans isomer.


Fourier Transform Nmr Self-Diffusion Studies Of A Nonaqueous Microemulsion System, K. P. Das, A. Ceglie, B. Lindman, Stig Friberg Jan 1987

Fourier Transform Nmr Self-Diffusion Studies Of A Nonaqueous Microemulsion System, K. P. Das, A. Ceglie, B. Lindman, Stig Friberg

Chemistry Faculty Research & Creative Works

Self-diffusion coefficients of the components of the microemulsion system glycerol/hexanol/sodium dodecyl sulfate (SDS) were determined in the presence and absence of an oil, p-xylene, and the results were compared with those from corresponding aqueous systems (i.e., glycerol replaced by water). In the aqueous system, the water in the hexanol rich isotropic liquid showed a diffusion coefficient less than 10% of that of free water, while that of hexanol was roughly 80% of that of free hexanol; such restricted motion of the water is consistent with the presence of water as discrete droplets. Partial substitution of p-xylene for hexanol did not …


Conductivity Study Of The Microemulsion System Sodium Dodecyl Sulfate-Hexylamine-Heptane-Water, Jiafu Fang, Raymond L. Venable Jan 1987

Conductivity Study Of The Microemulsion System Sodium Dodecyl Sulfate-Hexylamine-Heptane-Water, Jiafu Fang, Raymond L. Venable

Chemistry Faculty Research & Creative Works

Conductivity measurements on this system are interpreted in terms of the percolation and effective medium theories. From this interpretation, the ratio of hexylamine to sodium dodecyl sulfate in the microemulsion droplet surfaces can be deduced. Following that determination, it is possible to obtain approximate values for the radius of the water pools and the number and surface area of droplets per unit volume of the microemulsion system. © 1987.


Interobserver Reliability In The Interpretation Of Computed Tomographic Scans Of Stroke Patients, David Shinar, Cynthia R. Gross, Daniel B. Hier, Louis R. Caplan, Jay P. Mohr, Thomas R. Price, Philip A. Wolf, Carlos S. Kase, Irene G. Fishman, Joshua A. Barwick, Selma C. Kunitz Jan 1987

Interobserver Reliability In The Interpretation Of Computed Tomographic Scans Of Stroke Patients, David Shinar, Cynthia R. Gross, Daniel B. Hier, Louis R. Caplan, Jay P. Mohr, Thomas R. Price, Philip A. Wolf, Carlos S. Kase, Irene G. Fishman, Joshua A. Barwick, Selma C. Kunitz

Chemistry Faculty Research & Creative Works

Interobserver Reliability in Interpretation of Computed Tomographic Images Was Studied by Six Senior Neurologists Who Independently Evaluated on a Standardized Stroke Data Bank Form the Brain Lesions of 17 Patients. the Results Analyzed with K Statistics Yielded Moderate to Substantial Agreement on Most Items of Interest Including the Stroke Pathology and Anatomy. in General, the Levels of Agreement Were as High as Previously Reported for the Diagnosis of the Mechanism of the Stroke, and Much Higher Than on Many Stroke History Items and Items of Neurologic Examination. Excellent Agreement Was Obtained for the Detection of Infarcts and Intracerebral Hemorrhage, and …


Interaction Of Calcium With Hema/Maa Copolymers., Michael R. Van De Mark, N. D. Lian, M. Brandon, E. C. Eckstein Jan 1987

Interaction Of Calcium With Hema/Maa Copolymers., Michael R. Van De Mark, N. D. Lian, M. Brandon, E. C. Eckstein

Chemistry Faculty Research & Creative Works

Polymeric materials based upon 2-hydroxyethyl methacrylate (HEMA) have been extensively used, especially in biomedical applications. Several reports have appeared in the literature during the past 20 years regarding the behavior of these materials upon exposure to body fluids. The results of these studies have ranged from good biocompatibility to calcification. The presence of methacrylic acid (MAA), in HEMA-based copolymers gives rise to a swelling transition at pH 7. The present study relates the swollen volume of HEMA/MAA gels to the concentrations of calcium salts at a pH where the MAA is ionized, as would occur for implanted gels. This swollen …


Foams From Aqueous Systems Of Polymerizable Surfactants, Stig Friberg, Jia Hwa Fang Jan 1987

Foams From Aqueous Systems Of Polymerizable Surfactants, Stig Friberg, Jia Hwa Fang

Chemistry Faculty Research & Creative Works

Polymerization was made in aqueous foams stabilized by a combination of a polymerizable surfactant, sodium (ω)-acrylamidoundecanoate (NaAAU), and oleyl alcohol. The common two-phase foams stabilized by a monomolecular layer of surfactant were not sufficiently stable to allow polymerization in foamed form, nor were such foams obtained in the two-phase region of aqueous solution and the liquid crystalline phase of hexagonally packed cylinders. Sufficient foam stability was found first when the lamellar liquid crystal formed by the combination of oleyl alcohol, the NaAAU, and the water. These foams were polymerized and shown to retain the liquid crystalline structure after polymerization. © …


Critical Phenomena In Nonaqueous Microemulsions, Stig Friberg, Yuh Chirn Liang Jan 1987

Critical Phenomena In Nonaqueous Microemulsions, Stig Friberg, Yuh Chirn Liang

Chemistry Faculty Research & Creative Works

The pseudo ternary phase diagrams of the four-component system glycerol, sodium dodecyl sulfate, hexanol and decane with the weight ratio of hexanol to decane equal to 100/0, 90/10, 75/25, 50/50, and 25/75 were determined at 30°C. The systems gave only isotropic solutions and no liquid crystalline phases. The nonaqueous regions corresponding to the W/O microemulsion region in aqueous systems suggested critical behavior as demonstrated by the convergence of tie lines and by light scattering intensity which gave a pronounced maximum at the point of converging tie lines. This maximum was transferred to higher glycerol/hexanol ratios with added surfactant and to …


The Synthesis Of 2-Aryl-3-Fluoroalkoxy-1-Propenes And Some Potentially Useful Reaction Of These Systems, Joan E. Brown Jan 1987

The Synthesis Of 2-Aryl-3-Fluoroalkoxy-1-Propenes And Some Potentially Useful Reaction Of These Systems, Joan E. Brown

Retrospective Theses and Dissertations

This report discusses research involving the fluoroalkoxylation of 2-arylprop-1-en-3-yltrimethylammonium iodides and the useful synthetic application of the adducts formed. The present work includes: 1) reactions of several 2-arylprop-1-en-3-yltrimethylammonium iodides with the sodium salt of 2,2,2-trifluoroethanol; 2) reactions of several fluoroalkoxy alcohols with 2-(4-bromophenyl)prop-1-en-3-yltrimethylammonium iodide; and 3) the oxidation of 2-(4-chlorophenyl)-3-(2,2,2-trifluoroethyoxy)-1-propene using the Lemieux/von Rudloff reagent. This report reveals the experimental conditions and procedures used as well as spectral and physical data of all new compounds synthesized. Explanation is offered for a possible mechanism for the formation of these compounds and recommendations for future research are given.


Structure Of L,L-Diphenylarsenanium Bromide Monohydrate, J. A. Campbell, R. Larsen, C. Campana, Sheldon E. Cremer, A. Gamliel Jan 1987

Structure Of L,L-Diphenylarsenanium Bromide Monohydrate, J. A. Campbell, R. Larsen, C. Campana, Sheldon E. Cremer, A. Gamliel

Chemistry Faculty Research and Publications

No abstract provided.


Phosphorus Levels And Disease On Lupins, J W. Bowden Jan 1987

Phosphorus Levels And Disease On Lupins, J W. Bowden

Experimental Summaries - Plant Research

Trial 87LG39 (81LG29) 87ME62

Location: Pingaring.

It has been suggested that high levels of phosphorus application to lupins can reduce the impact of leaf and root diseases. Two old rotation trials provided a range of disease burdens, across which phosphate rates on lupins were applied. Disease scores, vegetative yields, phosphorus concentration and seed yields were measured.

(Details in Mark Sweetingham's report)


Hydration Of Propylene To Isopropanol, Nehemiah Diala Jan 1987

Hydration Of Propylene To Isopropanol, Nehemiah Diala

Retrospective Theses and Dissertations

The hydration of propylene to isopropanol was investigated. The first part of this study concerned the direct hydration reaction in various liquid phase systems in the presence of sulfuric acid or p-toluenesulfonic acid. The second part in a two-stage process in which propylene was contacted with excess acetic acid to form isopropyl acetate; the ester was then hydrolyzed to isopropyl alcohol and acetic acid.


Measurement Of The Condensation Coefficient Of Water In The Umr Simulation Chamber, Daniel R. White, James L. Kassner, John C. Carstens, Donald E. Hagen, John L. Schmitt, Darryl J. Alofs, Alfred R. Hopkins, Max B. Trueblood, Max W. Alcorn, William L. Walker Jan 1987

Measurement Of The Condensation Coefficient Of Water In The Umr Simulation Chamber, Daniel R. White, James L. Kassner, John C. Carstens, Donald E. Hagen, John L. Schmitt, Darryl J. Alofs, Alfred R. Hopkins, Max B. Trueblood, Max W. Alcorn, William L. Walker

Physics Faculty Research & Creative Works

The UMR Cloud Simulation Facility is described. The facility is designed to provide a controlled environment simulating the conditions of natural atmospheric processes. It consists of two cooled-wall expansion cloud chambers and peripheral instrumentation for generation and characterization of aerosols used for cloud formation studies. Results of initial studies of the growth of warm cloud droplets and inferred measurements of the condensation coefficient are described.


Reversible Oxygenation Of Oxygen Transport Proteins, Charles Michael Drain, Barry B. Cordon Jan 1987

Reversible Oxygenation Of Oxygen Transport Proteins, Charles Michael Drain, Barry B. Cordon

Publications and Research

A lecture demonstration illustrating changes in the visible spectra of oxygen transport proteins upon reversihle oxygen binding is reported. The coloration upon exposure to oxygen is dramatic. Deoxyhemoglobin changes from purple to red, deoxyhemocyanin is transformed from colorless to blue, while colorless deoxyhemerythrin turns red. This demonstration illustrates an interesting example of a chemically reversible reaction and is used in the discussion of basic thermodynamic properties. A comparison of the physical characteristics of these oxveen storaee and transn.o rt ~ro- A teins is provided to illustrate the stru&ral diversity associated with these proteins having a similar biological role.


Evaluation Of Existing Diagnostic Procedures For The Recommendation Of Trace Element Fertilisers, R F. Brennan Jan 1987

Evaluation Of Existing Diagnostic Procedures For The Recommendation Of Trace Element Fertilisers, R F. Brennan

Experimental Summaries - Plant Research

Trial 87N23

Location: Newdegate Research Station.

To compare the accuracy and reliability of a range of tissue and soil tests being variously promoted for use to farmers for the diagnosis and prognosis of zinc and copper deficiencies in wheat crops on Western Australian farms.


N X P X Irrigation On Wheat - South Carabin, J W. Bowden Jan 1987

N X P X Irrigation On Wheat - South Carabin, J W. Bowden

Experimental Summaries - Plant Research

Trial 87M7.

Nx P x irrigation on wheat

Although no major effects of fertilizer on average seed size were noted, it was found that phosphate level had an effect on the distribution of seed sizes.

Location: South Carrabin.


Trial 87WH51

1987 rainfall.

Location: Wongan Hills Research Station.


Harvested And Grazed Lupin Stubbles On Following Wheat South Carrabin., J W. Bowden Jan 1987

Harvested And Grazed Lupin Stubbles On Following Wheat South Carrabin., J W. Bowden

Experimental Summaries - Plant Research

Location: South Carrabin lease block

Harvested and grazed lupin stubbles on following wheat. Trial 86M8

This trial is difficult to analyze statistically because of the treatment changes induced by sheep breaking in to some of the plots. Further, lupin grain yields were not very high and so differences between harvested and unharvested treatments are not large. Also the grazing intensity was not very severe (except on the unintentionally grazed plots) and so the effect of grazing is also relatively small.

Trial 87M7

Nitrogen phosphorus and irrigation of wheat.

Location: South Carrabin.

This trial was designed to give a nitrogen/phosphorus response …


Residual Value Of Phosphate Fertilizers., M D A Bolland, M Baker, C. H. Phillips, D. Proudmore Jan 1987

Residual Value Of Phosphate Fertilizers., M D A Bolland, M Baker, C. H. Phillips, D. Proudmore

Experimental Summaries - Plant Research

Trial 84M63

Residual value of phosphate fertilizers.

Location: South Carrabin Block of Merredin Research Station.

4th successive crop on new land. Trial has shown that the effectiveness of the different types of rock phosphate were about the fifth to one tenth as effective as the fresh (triple) superphosphate applied in 1984. The effectiveness of the superphosphate, decreased by 60 between year 1 and 2, and by a further 10-15% by 1987. This experiment will continue as pasture for 1988 and 1989, and will be re-cropped in 1990. The experiment is also assessing soil testing for P. but soil test data …


Primary And Secondary Basis Set Superposition Error At The Scf And Mp2 Levels. H3n‐‐Li+ And H2o‐‐Li+, Zdzisław Latajka, Steve Scheiner Jan 1987

Primary And Secondary Basis Set Superposition Error At The Scf And Mp2 Levels. H3n‐‐Li+ And H2o‐‐Li+, Zdzisław Latajka, Steve Scheiner

Steve Scheiner

The primary basis set superposition error (BSSE) results from the artificial lowering of the energy of each subunit of a pair by the presence of ‘‘ghost orbitals’’ of its partner. In addition, these ghost orbitals perturb the one‐electron properties of the molecule, causing a change in the interaction energy, an effect known as secondary BSSE which is not corrected by the counterpoise procedure. The primary and secondary BSSE are calculated for the interactions of NH3 and H2O with Li+, using a variety of different basis sets. It is found that the 2° BSSE can be …


Vibrational Frequencies And Intensities Of H-Bonded Systems. 1:1 And 1:2 Complexes Of Nh3 And Ph3 With Hf, I. J. Kurnig, M. M. Szczesniak, Steve Scheiner Jan 1987

Vibrational Frequencies And Intensities Of H-Bonded Systems. 1:1 And 1:2 Complexes Of Nh3 And Ph3 With Hf, I. J. Kurnig, M. M. Szczesniak, Steve Scheiner

Steve Scheiner

Frequencies and intensities are calculated by ab initio methods for all vibrational modes of the 1:1 H3X–HF and 1:2 H3X–HF–HF complexes (X=N,P). The HF stretching frequencies are subject to red shifts, roughly proportional to the strength of the H bond, and to manyfold increases in intensity. Although the intramolecular frequency shifts within the proton acceptors are relatively modest, the intensities of the NH3 stretches are magnified by several orders of magnitude as a result of H bonding (in contrast to PH3 which exhibits little sensitivity in this regard). …


Simple Scheme For Variable High Power Laser Beam Attenuation, Stephen E. Bialkowski Jan 1987

Simple Scheme For Variable High Power Laser Beam Attenuation, Stephen E. Bialkowski

Stephen E. Bialkowski

A venetian style infrared attenuator placed prior to a pinhole spatial filter results in variable high‐power laser attenuation. This attenuation scheme has a wide dynamic range, results in high‐quality Gaussian beams, does not introduce beam walk‐off error, and is independent of polarization.


Optimal Estimation Of Impulse‐Response Signals Through Digital Innovations And Matched Filtersmoothing, Stephen E. Bialkowski Jan 1987

Optimal Estimation Of Impulse‐Response Signals Through Digital Innovations And Matched Filtersmoothing, Stephen E. Bialkowski

Stephen E. Bialkowski

A real‐time digital filter is described which may be most useful for optimal determination of the magnitude of impulse‐response functions found in pulsed, repetitive experiments of low duty cycle. This filter is based on a matched filter but employs an interference orthogonalization step. This results in a signal magnitude estimate which is independent of coherent interference. The filter updates the signal magnitude estimate upon each repetition of the experimental cycle. Comparisons to signal estimation using gated sampling devices are given.