On the Curious Resemblance Between Fly Ash and Meteoritic Dust

This paper is a discussion of W. J. Thomsen\u27s prize-winning paper presented to the Geology Section of the Iowa Academy of Science in 1952 and entitled The Annual Contribution of Meteoritic Dust to the Mass of the Earth (1). The present paper presents evidence that Thomsen\u27s unusually high estimate for the annual deposition of meteoritic dust may be due to the presence of fly-ash in the magnetic dust samples he collected

Depth Studies of the Wisconsin Loess in Southwestern Iowa: I. Particle-Size and In-Place Density

The Soil Research Laboratory of the Iowa Engineering Experiment Station has been studying areal and stratigraphic variations in properties of the Wisconsin (Peorian) loess in southwestern Iowa since September, 1950. The information on loess properties is being utilized in soil stabilization studies now in progress. A paper presented before the Geology Section of the Iowa Academy of Science in 1952 (1) discussed the distribution of and some property variations in the Wisconsin loess in the southwestern Iowa area shown by Figure 1. While last year\u27s paper presented some depth data, the main emphasis was on areal property variations. More detailed studies of selected Wisconsin loess sections are now in progress to determine the variations in properties with depth. The present paper, Part I of two parts, presents particle-size, field moisture, and in-place density data. Part II will cover chemical, mineralogical, and additional physical property data

Variation of Loess Thickness and Clay Content in Southern Iowa

This report summarizes two aspects of the Wisconsin loess in southern Iowa and presents some information on the sandy-silt immediately underlying the loess and overlying the till in southcentral Iowa. The data has originated from project work done over the last five year on the loess and glacial till of Iowa (Project 283-S) in .an attempt to solve the problem of stabilization of loess and till for roads. This paper incorporates data procured to date on the loess of southwest, southern and east-central Iowa and present studies in progress in south-central Iowa. (See references 1, 2, 3 and 4.

The haemolytic effect of verapamil on erythrocytes exposed to varying osmolarity

The haemolytic effect of verapamil on red blood cells (RBCs) exposed to varying osmolarity was investigated. The experimental approach used a modified red cell haemolysis assay with concentrations of verapamil ranging from 50–1500 lM compared to drug free controls. The timecourse of haemolytic effects was also investigated. We also briefly determined the haemolytic effects of verapamil in Ca2+-free conditions (with added EGTA). In conditions representing decreasing osmolarity (dilution from 140–0 mM NaCl) there was a significant increase in erythrocyte haemolysis that was also dependent on verapamil concentration (ANOVA, p < 0.05). The red cells also showed a significantly increased rate of haemolysis over 5 h with increasing verapamil concentration (ANOVA, p < 0.05). The degree of RBC hypotonic haemolysis was significantly increased in a Ca2+-free medium (+EGTA) compared to normal saline and this effect was exacerbated by additions of verapamil (ANOVA, p < 0.05). Overall the data suggested that verapamil can cause haemolysis of RBCs in a predictable time- and concentration-dependent manner, and that verapamil increases the fragility of the erythrocytes further during hypotonic osmotic stress and Ca2+-free conditions. The mechanism of verapamildependent haemolysis could be directly related to the observed biphasic concentration-effect and could consequently involve several ion transport pathways

Dynamics of the solar chromosphere. V. High-frequency modulation in ultraviolet image sequences from TRACE

We search for signatures of high-frequency oscillations in the upper solar photosphere and low chromosphere in the context of acoustic heating of outer stellar atmospheres. We use ultraviolet image sequences of a quiet center-disk area from the Transition Region and Coronal Explorer (TRACE) mission which were taken with strict cadence regularity. The latter permits more reliable high-frequency diagnosis than in earlier work. Spatial Fourier power maps, spatially averaged coherence and phase-difference spectra, and spatio-temporal k-f decompositions all contain high-frequency features that at first sight seem of considerable intrinsic interest but actually are more likely to represent artifacts of different nature. Spatially averaged phase difference measurement provides the most sensitive diagnostic and indicates the presence of acoustic modulation up to f=20 mHz (periods down to 50 seconds) in internetwork areas.Comment: 9 pages, 8 figure

Portland Cement Contents Required to Stabilize Eastern and Western Iowa Loess

Because of existing and predicted future shortages of road-building aggregates, the Iowa State Highway Commission has for several years sponsored research programs to find satisfactory substitutes. A major part of these investigations has been to investigate possible chemical treatments to waterproof and harden natural soils. In locations of most critical aggregate shortages in Iowa, loess, a fine silt soil, is often the major surficial material, and present investigations have been concerned mainly with loess in Iowa. During successive project years different loess soil areas in Iowa have been studied, first to determine petrographic and engineering properties of the soils and second to systematically examine various soil stabilizers with the object of selecting the most promising through laboratory tests. Considering the extremely wide variety of chemicals tried and the various stabilization principles involved, it is significant that one, treatment has remained consistently near the head of the list-that of stabilizing soil by adding water and Portland cement. Compacted mixtures of cement and water and soil, termed soilcement , have been used as road base materials since about 1935, and many roads using this material have long and successful service records. The growth in. nationwide utilization of soil-cement has been most rapid in recent years, but perhaps as important is the fact that the advent of soil-cement marked the beginning of modern chemical soil stabilization, and field and laboratory procedures adopted for soil-cement have strongly influenced the investigations of other chemicals

Space of State Vectors in PT Symmetrical Quantum Mechanics

Space of states of PT symmetrical quantum mechanics is examined. Requirement that eigenstates with different eigenvalues must be orthogonal leads to the conclusion that eigenfunctions belong to the space with an indefinite metric. The self consistent expressions for the probability amplitude and average value of operator are suggested. Further specification of space of state vectors yield the superselection rule, redefining notion of the superposition principle. The expression for the probability current density, satisfying equation of continuity and vanishing for the bound state, is proposed.Comment: Revised version, explicit expressions for average values and probability amplitude adde

Effect of Ca-Montmorilionite Expansion on X-ray Diffraction lntensities

The most abundant clay mineral group in Iowa soils is montmorillonite, most commonly calcium-saturated (Hanway et al. 1960). The calcium montmorillonite-water system was therefore selected for detailed X-ray study. Montmorillonite is unusual among minerals in that it has an expansible lattice in the c direction. That is, upon wetting with water, the individual silicate layers separate to allow entry of water, and the mineral expands. Characteristics of expansion are readily studied by means of X-ray diffraction: the X-ray diffraction angle gives the average layer-to-layer d001 spacing for any given moisture condition; the sharpness of the diffraction peak is a measure of uniformity of the d001 spacing; and the intensity of the peak relates to uniformity of the d001 spacing and in addition to the electron density distribution within the repeating elements. The latter is embodied in the structure factor . The variation of d001 structure factor caused by montmorillonite expansion is the subject of this paper

Property Variations in the Wisconsin Loess of East-Central Iowa

As part of a long-range project to investigate the stabilization of loess and glacial till for low cost road construction, property studies of the Wisconsin loess of east-central Iowa were carried on at the Engineering Experiment Station of Iowa State College during the year 1952-1953. Previous work 1,2,3,4 1950-1952, dealt with the properties of the Wisconsin loess of southwestern Iowa; stabilization studies are now under way with the loess from that area. In east-central Iowa, the loess was studied with a two-fold objective: to determine the variations in properties pertinent to stabilization, and to compare these properties with those of the southwestern Iowa loess. This paper reports only on the property variations

Analyses of Wind-Blown Silt-March, 1954

Recent project work in the Soil Research Laboratory of the Iowa Engineering Experiment Station has been focused on studies of loess in Iowa. Since most geologists believe that loess was carried and deposited by the wind, members of the Engineering Experiment Station have long been interested in seeing silt-laden winds in action. This means visiting dust storms, and opportunities for study have been infrequent during the past 15 years. Recent developments in the southwest have changed this somewhat, and dust storms are once again plentiful. The combination of drought and strong winds has sent dust from Kansas and Colorado into many Mid-Western states, and recently an average depth of one-sixteenth inch was deposited in Iowa from one storm. In addition to studying dust which settled in Ames, two of the authors visited the most severe dust areas of southwestern Kansas and the Oklahoma and Texas panhandles.· The purpose of the trip was to obtain some sand samples for a separate stabilization study, and incidentally to try to locate some dust storms. Both efforts were eminently successful