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A Crystalline Fragment Of The Double Helix: The Structure Of The Dinucleoside Phosphate Guanylyl-3',5'-Cytidine, Roberta Ogilvie Day, Nadrian C. Seeman, John M. Rosenberg, Alexander Rich

Department of Chemistry: Faculty Publications

The sodium silt of guanylyl-3',5'-cytidine crystallizes in a monoclinic unit cell with one molecule in the asymmetric unit. Each molecule is related to another molecule by a 2-fold rotation axis which results in the formation of an antiparallel; right-handed .double helix with complementary hydrogen bonding between the guanine and cytosine residues. The crystal is heavily hydrated with 36 water molecules in the unit cell. The geometry of this crystalline double helix is. very similar to those which have been derived from studies of fiber x-ray diffraction patterns of double-stranded RNA; even though the latter do not yield data at atomic …

Production And Decay Of Double L Vacancies In Argon And Phosphorus, M. Eugene Rudd, B. Fastrup, P. Dahl, F. D. Schowengerdt

M. Eugene Rudd Publications

Measurements have been made at two laboratories which indicate that the structure reported at 450-550eV in the electron spectrum from Ar⁺-Ar collisions by Ogurtsov, Flaks, and Avakyan is spurious. It is argued that the double L vacancies which they invoke to explain the structure are more likely to decay by the two-step Auger process L ²→LM²→M⁴ than by the one-step process L²→M³ suggested by these authors. Evidence supporting this is found in our electron spectra from P⁺-Ar collisions, where it is known from energy-loss and charge-state measurements that double …

Photochemical Rearrangements Of 6/5 -Fused Cross-Conjugated Cyclohexadiensnes In Protic Solvents, Drury Caine, John T. Gupton, Ko Ming, William J. Powers Iii

Chemistry Faculty Publications

Irradiation of the ring A unsubstituted 6/5-fused cross-conjugated cyclohexadienone (1a) and its 2-methyl derivative (1b) in methanolic acetic acid yields, in addition to other products, novel tricyclononane derivatives which have been assigned the structures (3a) and (3b).

Tchebycheff Approximation On A Discrete Point Set: Algorithms Old And New, William Edward Mcbride

Doctoral Dissertations

"Several linear and nonlinear algorithms for solving the discrete Tchebycheff problem are compared in this study. The Lawson algorithm is compared with two more well-known methods of linear Tchebycheff approximation. A new acceleration scheme for the Lawson algorithm is introduced and its performance is tested with an already existing acceleration technique. The new version is found to be better than the previous one but not as effective as the traditional Exchange method.

A nonlinear version of Lawson's algorithm is proposed for the solution of problems having approximating functions which are varisolvent. Some linear theorems of Lawson are extended to the …

Hall Effect Measurements Of The Net Ionic Mobility In Nacl, Nabr And Nai, Suman Kumar Hukku

Doctoral Dissertations

"Ac Hall effect measurements of the net ionic mobility, µ_H, in "pure" NaCl, NaBr and Nal were made over their intrinsic temperature ranges extending up to about 250⁰ C below the crystal melting point. A well characterized detector system was employed which provided a mobility sensitivity ≥ 2 x 10^-4 cm² · V^-1 · s^-1. Complementary electrical conductivity, σ, data was also collected. The charge transport was assumed to be due to Schottky defects and both cation and anion contributions were considered. The high temperature anion contribution to mobility was clearly demonstrated by …

Giant Loops As Fossil Stromgren Spheres: Their Radio And X-Ray Emission, Menas Kafatos, P. Morrison

Mathematics, Physics, and Computer Science Faculty Articles and Research

The loops are examined as radio and soft X-ray sources under the assumption that they are objects related to the Gum Nebula but much older than it. The loop diameters are likely on the scale of 100 pc or more, as reported recently. This is naturally understood with the fossil Stromgen sphere model. Further progress in understanding the origin of the loops depends on the resolution of certain observational issues.

Corals Of The St. Louis Limestone In The Area Of Calhoun County, Illinois And St. Louis County, Missouri, William Earl Collins

Masters Theses

"The St. Louis Limestone and its equivalent formations crop out from Alaska south to Sonora and from Arizona east to Virginia. The St. Louis, in most cases, is fossiliferous and contains numerous species of foraminifers, echinoderms, bryozoans, molluscans, brachipods, arthropods and coelenterates. Algal mounds and mats are common. The rugose coral fauna of the Middle Mississippian (Meramecian) St. Louis Limestone of southern Calhoun County, Illinois and northern St. Louis County, Missouri was studied to determine first what corals were present and second the validity of the names assigned to the previously described species. It was found that the binomen for …

Scavenging Of Atmospheric Particles By Water Drops, Ming-Shian Wu

Doctoral Dissertations

"In the first paper, the mechanisms of particle capture and coalescence of aerosols by a moving water drop in the atmosphere are studied using the boundary-layer flow approximation. The particle trajectory is computed by solving the equations of motion of the particle both outside and inside the boundary layer using the Adams-Moulton method. The grazing trajectory is found by a trial-and-error technique. The collision and collection efficiencies of scavenging due to particle inertia and to the velocity gradient of the flow field are then computed for water drops ranging from 0.1 to 1.0 mm in radius and for particle of …

Model Correction For The Formation Of Amorphous Silicon By Ion Implantation, John Robert Dennis

Masters Theses

"ESR has been used to study the formation of an amorphous layer in silicon by ion implantation. The room temperature implants were done at 20 keV with low dose rates. The critical dose was determined as a function of ion mass for six different ion species. Our experimental heavy ion results agree with those found by other ESR investigators at higher energy, but are not the same for light ions. However, our light and heavy ion results agree with electron microscope measurements for low energy implants. An energy-independent model for the formation of amorphous silicon by ion implantation has …

The Prairie Naturalist Volume 4, Nos. 3 And 4. September–December 1972

The Prairie Naturalist

THE SANDHILL CRANE WITH EMPHASIS ON ASPECTS

RELATED TO NORTH DAKOTA ▪ Douglas H. Johnson and Robert E. Stewart

SIZE AND COLORATION CHARACTERISTICS OF NEOTENIC SALAMANDERS IN DEVILS LAKE, N. D. ▪ Douglas W. Larson

BIRDS' EGGS: AN AID TO NATURE APPRECIATION ▪ S. O. Kolstoe

BIRD MORTALITY AT FOUR TOWERS IN EASTERN NORTH DAKOTA — FALL 1972 ▪ Michael Avery and Tom Clement

POPULATION IRRUPTION OF THE LEAST WEASEL (Mustela nivalis) IN EAST CENTRAL NORTH DAKOTA ▪ John T. Lokemoen and Kenneth F. Higgins

On Improved Wkb (Uniform Asymptotic) Quantum Conditions, Dunham Corrections, The Langer Modification, And Rkr Potentials, Russell T. Pack

Faculty Publications

An improvement to the WKB quantum condition for the rotation-vibration levels of diatomic molecules, known empirically to give RKR potentials of increased accuracy and to account for the Dunham correction Y00, is derived using uniform asymptotic methods. The role of the Langer transformation in this problem is also discussed.

Decay Of Multiple Spin Echoes In Dipolar Solids, C. H. Wang, John D. Ramshaw

Physics Faculty Publications and Presentations

In this paper we derive a general expression describing the evolution of the transverse nuclear-spin magnetization for the Ostroff-Waugh multiple-spin-echo experiment in dipolar solids. Our approach consists of expressing the formula for the magnetization at even echoes in a form resembling an ordinary time-correlation function, and then evaluating this quantity by means of Zwanzig's projection-operator technique. For long times, we show that under certain conditions the echo envelope decays exponentially, in agreement with experiment. A general expression is obtained for the time constant T^* associated with the decay. This result may be used to generate an expansion of 1T …

Water Resources News, Volume 4, No. 9, November 1972

Water Current Newsletter

Conference Proceedings Available
Assistance Grants for Nebraska
Niobrara, Nebraska - Moving
Congress Heaps CEQ Report
Bureau Studies Saline Water
New Administrative Regions for USGS
Unfair Attacks on Pesticide Pollution
Numerical Designation of Bureau Regional Offices Obsolete
Water Pollution Control Measure Becomes Law
Gavins Point Dam
Water Dollars Down the Drain
Federal Pollution Laws
New Food Industry Uses Heated Water
War Between the Worlds
Waste Discharge Exceptions Banned
National Water Commission Report

Magnetic And Thermometric Properties Of Na3[Ce(C7h3no4)3] ·15h2o In The Millikelvin Range, Richard A. Webb, J. C. Wheatley

Faculty Publications

Measurements of the 16-Hz susceptibility of a powdered Na₃[Ce(C₇H₃NO₄)₃] · 15H₂O (CDP) sample, in the shape of a right-circular cylinder with diameter equal to height, have been made as a function of the Johnson noise temperature T_J of a resistor in the range 2 to 20 mK. Pure liquid ³He was used for thermal contact between the CDP and the noise thermometer in a demagnetization cell. The results are compared with similar data for cerium magnesium nitrate (CMN). CDP appears, like CMN, to have an anomalously …

Linear Estimation: The Kalman-Bucy Filter, William Douglas Schindel

Graduate Theses - Mathematics

The problem of linear dynamic estimation, its solution as developed by Kalman and Bucy, and interpretations, properties and illustrations of that solution are discussed. The central problem considered is the estimation of the system state vector X, describing a linear dynamic system governed by

dx/dt = F(t)X(t) + G(t)U(t)

Y(t) = H(t)X(t) + V(t)

for observations of Y (system output), where V is a random observation-corrupting process, and U is a random system driving process.

An extension of the Kalman-Bucy filter to estimation in the absence of priori knowledge of the random process U and V is developed and illustrated.

Press Reports, Walter A. Lawrance

Walter Lawrance Papers

No abstract provided.

Existence Of The Dielectric Constant In Rigid-Dipole Fluids: The Direct Correlation Function, John D. Ramshaw

Physics Faculty Publications and Presentations

The question of whether the dielectric constant ε exists (is well defined) for a finite fluid system of rigid dipolar molecules is reconsidered and reformulated. It is found that this question can most simply be expressed in terms of the behavior of the position‐ and orientation‐dependent direct correlation function c(r₁,ω₁; r₂, ω₂). It is shown that ε exists if c satisfies the following two conditions: (a) c~–φ/kT for |r₁–r₂|>σ, where φ is the dipole‐dipole potential and σ is a length which is large microscopically but small macroscopically. …

Nebraska Tractor Test 1110 John Deere 4430 Quad -Range Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

All lest result s were determined from observed data obtained in accordance with SAE and ASAE test code or official Nebraska test procedure. First and second gears were not run as it was necessary to limit the pull in third gear to avoid excessive slippage. Fourth, tenth, eleventh, twelfth, thirteenth, fourteenth , fifteenth and sixteenth gears were not run as test procedure requires only six travel speeds. During maximum drawbar run in 3rd gear the transmission came out of gear twice making it necessary to hold the shift lever in place to complete the run.

Morphologic Time Series From A Submarine Sand Ridge On The South Virginia Coast, John F. Mchone Jr.

OES Theses and Dissertations

Submarine sand ridges several km long locally merge southward into the U. S. Atlantic coastline. Shallow (< 8m) observations of -such a ridge at False Cape, Virginia, favor a modern hydraulic origin. Time series maps show the ridge to be paralleled by a landward trough of approximately equal volume. Ridge flanks are usually steeper on the trough side.

Northeasterly winds and waves generate a coast-parallel current which funnels southward into the trough scouring it out and providing sediments for ridge aggradation. The current may be organized as a helical flow cell or cells. Bottom currents converge southward along the ridge crest causing landward transport of traction load along the crest. The trough current eventually breaches the confining ridge at the head of the trough, cutting saddles with steeper seaward slopes and producing outlying sediment fans.

The ridge and trough rest obliquely …

Air Bubbles In An Oceanic Mixed Layer: Effect On Gas Concentrations And Air-Sea Gas Exchange, Larry P. Atkinson

CCPO Publications

This thesis attempts to determine the effect of air bubbles that are entrapped into the surface layers of the ocean by breaking waves on gas concentrations in the ocean and gas exchange across the air-sea interface. N₂ and Ar data gathered during the Hudson-70 expedition produced indications of the magnitude and nature of the effect. A mathematical model is developed that equates the input of gas via bubble solution with the vertical eddy diffusion. Published values for bubble spectra and solution rates are used and assumptions are made concerning the effect of wind on bubble spectra. The model predicts …

Bulletin No 3867 - Water For Agriculture. Clearing Cloudy Or Coloured Water, N. E. Platell

Bulletins - 3000 - 3999

THE suspended material in most water supplies is generally clay, although sometimes organic matter and materials precipitated from solution, such as hydrated iron oxides, may be present. Coloured waters are those waters that are still coloured, due to dissolved coloured matter, after suspended material has been removed. Some coloured waters such as those found in swampy areas may be entirely free of suspended material.

The amount of clay or colour present is mainly of concern where the water is used for household purposes. Only rarely is the clay or colour present in such quantities that the water is undrinkable for …

Terminal Talk - The Wofford Connection - September 1972, Wofford College Computer Center

Terminal Talk

No abstract provided.

A Preliminary Bibliography And Lake Index Of The Inland Mineral Waters Of The World, D. B. Mccarraher

Nebraska Game and Parks Commission: Staff Research Publications

This preliminary- bibliography and lake index has been prepared by the author on the basis of information available in the Office of Limnology, Hastings College, Nebraska. Although all source material available there has been searched, it is recognized that many papers, especially those published in regional languages may have been left out. Readers are requested to point out such omissions and any inaccuracies that require correction.

This preliminary bibliography will be circulated among specialists in the subject for corrections to the citations and for suggested additions to the list. It is planned that the paper will then be revised to …

New Method For Generating Density Expansions, John D. Ramshaw

Physics Faculty Publications and Presentations

The calculus of finite differences is used to develop a new method for expressing the thermodynamic limit of a reasonably arbitrary statistical?mechanical average as a power series in the number density ?. The method is simple, straightforward, and purely analytic: it involves no intermediate expansion in powers of the activity and it avoids the use of graph theory. Moreover, the method is developed independently of the prescription for computing the statistical average, a fact which lends to the results an especially wide range of applicability. In particular, these results may be used in classical or quantum statistical mechanics, for intermolecular …

X-Ray Diffraction Studies On Liquids At Very High Pressures Along The Melting Curve. I. Methods And Techniques, Keith H. Brown, J. Dean Barnett

Faculty Publications

A technique using the tetrahedral anvil high-pressure x-ray system has been developed to extract coherent x-ray intensity patterns of liquids near melting from measured scattering curves in the presence of high-background counts. Radial distribution functions for liquids along the melting curve to pressures of at least 50 kbar can be obtained. At each pressure scattering curves are recorded for the liquid and solid on opposite sides of the melting curve and a subtraction is made to eliminate background and incoherent scattering. Theoretical estimates of the thermal diffuse scattering from the solid are added to the appropriately corrected difference patterns to …

Kinetics Of The Cope Rearrangement Of 3,4-Diphenylhexa-1,5-Diene, Harlan Albert Jerome Berg

Dissertations and Theses

Kinetics investigations of the thermal Cope rearrangement of meso- and dl-3,4-diphenylhexa-1,5-dienes were undertaken in order to gain information about the transition states for these reactions by determining the appropriate enthalpies and entropies of activation. Of particular interest were the activation parameters for the meso compounds' rearrangement as it represents the only known example in which both four- and six-centered transition states are of comparable energy.

Kinetics of the dl isomers' rearrangement in the temperature range 90-110° were determined using 5 X 10^-5 M solutions of the olefin in heptane contained within sealed Pyrex ampules. Extents of reaction …

Measurements Of The Mössbauer Fraction In Chromium, B. Frederick Brace Jr.

Dissertations and Theses

Precision measurements of the Mossbauer fraction of Fe57 in chromium were made using the black absorber technique over a range of temperatures from 78K to 792K. Because of uncertainty in corrections at high temperatures, only the data collected from 78K to 600K was used in analyzing the results.

The f values were analyzed in terms of a Debye approximmation. This analysis of the data yielded a theoretical fit which was based on two adjustable parameters (a Debye temperature of 438K and an anharmonicity parameter of 2 x 10^-4K^-1).

The f measurements were also analyzed using a …

Frenkel Defects In Alkali Halides, Paul Schulze, John Hardy

John R. Hardy Papers

The method of lattice statics and the deformation dipole model have been applied to Frenkel defects in ionic crystals. For isolated interstitials, all short-ranged repulsive and Coulomb-defect host-lattice ion forces were evaluated at the relaxed configuration. The zero-order Coulomb force was allowed to act on the remainder of the host-lattice ions past first neighbors. We have calculated Frenkel-pair formation energies, ionic displacements, and ionic polarizations in the twelve Na, K, Rb halides. Our results show over all that, in ionic crystals of the rocksalt structure, Schottky defect pairs are more likely to be present than Frenkel defect pairs.

Nuclear-Magnetic-Resonance Study Of Co2+ In Cds, David C. Look, Donald R. Locker

Physics Faculty Publications

Nuclear spin-lattice relaxation times, T₁, have been measured over a temperature range T=(1.1-300) °K and frequency range ν=2-15 MHz in a single crystal of CdS doped with 13-ppm cobalt. Minima in T₁ vs T are observed, and absolute values of the effective electron relaxation time, τ_e, may be calculated at the temperatures of the minima, e.g., at 14 °K, τ_e=8.0×10^-8 sec. At low temperatures, T≲5 °K, τ_e is dominated by a resonant Orbach process involving the two ground-state Kramers doublets (S=±3/2 and S=±1/2) which, according to our measurements, are split by …

Hydrostatic Pressure Effects On The Epr Spectrum Of V2+: A1203 And Cr3+: A120, Charles J. Wilcox

Masters Theses

No abstract provided.