This research project is concerned with liquid-liquid extraction. Specifically, it is a study of the mechanisms of solute transfer in spray towers. A theory is proposed which postulates the existence of three separate stages of solute transfer. These stages of extraction and the operating variables which seem to affect them are discussed.
In recent years, the spectrum of stress phenomena, ranging from the tragic to the mundane, has received a great deal of attention in the research literature. Research has found that exposure to a broad range of stress phenomena increases the risk for subsequent psychopathology (Kanner, Coyne, Schaefer, & Lazarus, 1981; Lewinsohn, Mermelstein, Alexander & MacPhillamy, 1985). The assumption that stress phenomena vary along a continuum from mild to severe underlies much of this research (Dohrenwend & Dohrenwend, 1978). Trauma has been understood to constitute the class labelled severe, life event stress (LES) the moderate, and daily hassles (DH) the mild. In empirical studies, these classes have thus been assumed to vary in terms of degree (i.e., quantity) rather than in terms of qualitative differences.
In unhairing operations, the tanner desires a dis-solution of the epidermis with a minimum breakdown of hair and corium tissues. Comparatively little is known about the chemical structure of epidermis, due to practical difficulties in obtaining relatively complete, unmodified, uncontaminated samples of this tissue. Epidermis for this work was obtained from three animals by two methods calculated to yield a minimum of modification. These methods were (1) removal at less than 10°C with dilute sodium chloride solutions, with precautions taken against bacterial action, and (2) removal by the action of distilled water at 60°C. for a period of ten minutes.
Metaplastic charges due to vitamin A-deficiency and overstimulation with estrogen were studied in the uterus of the rat. The investigation was concerned with the following problems: (1) the role of the ovaries in producing uterine metaplasia in vitamin A-deficient rats; (2) whether uterine metaplasia which is induced by estrogen is a gradual process or a rapid one, which takes place a short time after the beginning of treatment; (3) whether the age of the animal at the start of estrogen treatment has any effect on the production of metaplasia; and (4) a cytologic comparison of the metaplastic processes resulting from vitamin A-deficiency with those resulting from overstimulation with estrogen.
Empathy was investigated as a multidimensional construct, including affective, cognitive, and communication processes. Observer subjects, who were administered the Interpersonal Reactivity Index (Davis, 1980), the State-Trait Anxiety Inventory (Spielberger, 1983), and the Social Skills Inventory (Riggio, 1989), rated the level of Expresser nervousness in anxious and comfortable videotapes. Those Observers reporting high affective empathy and high cognitive empathy also reported higher skill in nonverbal communication decoding and interpretation. However, highly empathic Observers did not report higher verbal communication decoding and interpretation skills. Contrary to previous research, those Observers low in affective empathy and high in trait anxiety showed significant increases in their state anxiety level after watching the anxious Expressers' videotape. The Observers, regardless of their reported level of cognitive empathy and trait anxiety, were able to differentiate anxious versus comfortable Expresser videotapes. The results are discussed in terms of their implications for empathy theory.
This paper consists of three parts. Part I is gravity wave growth, saturation and decay with height; part II reflection of gravity waves from critical layer using realistic background atmosphere and background wind; part III perturbation treatment of minor species' response to gravity waves. In part I by using Newtonian cooling and Rayleigh friction approximations and by considering only the average effects of turbulence on gravity waves we have derived an optical potential, with which we have studied the propagation of gravity waves and their reflections at every height level. We have found that reflections from higher level due to viscosity and heat conduction is so small that no ducting can be sustained. part II is the continuation of He Fan's work. In our work we adopt the same two parameter optical potential to model the gravity wave--critical layer interaction but we relaxed the conduction of isothermalness of the background and the linearity of the wind profile and we use the more realistic wind models, so our results should be more meaningful. We have found that the reflection coefficients of gravity waves from critical layer range from 5% to 25%, which should be measurable. In part III we develop a perturbation scheme with which it is possible to calculate the minor species response to any order in the linear gravity wave, including a secular component of the response which leads to wave-induced diffusion of minor species. Calculations to third order over a wide range of wave parameters show that the nonlinear effects can be substantial. A result is that care must be taken when analyzing data from minor species fluctuations, so that frequencies due solely to the nonlinear nature of the minor species response are not attributed to gravity waves.
I conducted melting experiments with a basanite, two hawaiites (DVDP2 and 83415), and a phonolite from Mt. Erebus, Antarctic. All experiments were carried out a 1 atmosphere from 1224$\sp\circ$ to 1049$\sp\circ$C at oxygen fugacity near QFM buffer. I have tested two hypothesis: (1) can a basanite parent magma differentiate at low pressures to produce hawaiite and phonolite magmas, and (2) do the Mt. Erebus rocks represent low pressure differentiation of a parental basanitic magma. Microprobe analyses of glasses and coexisting crystals were used to test these hypotheses.
The purpose of this dissertation were threefold: (1) to develop a taphonomically-based facies (taphofacies) model for a classic, modern carbonate system, the south Florida shelf; (2) to compare and contrast the south Florida taphofacies model to the only other published modern carbonate taphofacies model, that of Parsons (1992) study of the northeastern Caribbean; (3) to compare and contrast a taphofacies model developed from the total mollusc assemblage (pooled sample approach) to models that only evaluate taphonomic changes within a single taxon as it occurs in different environments.
Metamorphism in the Ollo de Sapo Antiform, part of the Variscan Orogen in NW Spain, was controlled by local, complex interactions of deformation, granitoid intrusions, and regional low pressure metamorphic (LPM) gradient. Detailed analysis of mineral parageneses, in conjunction with geothermobarometry and one-dimensional thermal modeling, have been used to constrain pressure-temperature-deformation (P-T-D) paths for rocks in the antiform.
The Richmond Group (Late Ordovician) in the tristate region of southwestern Ohio, north-central Kentucky, and southeastern Indiana consists of a succession of clastic and carbonate sediments deposited on a prograding intracratonic ramp and distal clastic fan. Six regional depositional facies have been delineated during a detailed examination of cores, outcrops, and geophysical logs across a 325 by 350 km study area. The facies, informally designated Facies A through F, are assigned to depositional environments consisting of: a shale-dominated shale distal intracratonic ramp; mixed carbonate and shale proximal intracratonic ramp; shallow subtidal to supratidal intracratonic ramp, and shallow-water, distal clastic wedge; based on their sedimentologic and paleontologic characteristics. Regional cross sections of these facies indicate that the distal clastic wedge prograded from the east and that the intracratonic ramp prograded from the south. In addition, isopach maps indicate that the depocenter of the basin was located southeastern Indiana and southwestern Ohio.
The Coalinga, California region contains massive amounts of diapirically emplaced deposits of serpentinite. The largest deposit, the New Idria Formation, forms the core of the Joaquin Ridge Anticline and outcrops over an elliptically-shaped 48-square mile area in a mountainous area 17 miles northwest of Coalinga and 15 miles west of the California Aqueduct constructed along the western margin of the San Joaquin Valley. The serpentinite deposit is in faulted diapiric contact with Cretaceous-aged sandstones and shales and became emergent approximately 17 to 20 million years ago in the Miocene era. Eroded asbestos-bearing sediment from this ultramafic deposit has been incorporated in late-Miocene and younger sedimentary formations in the central San Joaquin Valley region.
The Miamitown shale has been considered an enigmatic unit in the upper part of an Edenian-Maysvillian sequence. A new look at Cincinnatian sequences reveals that this unit is actually an integral part of a complex sequence architecture. Three fourth-order sequences at the base of the Upper Ordovician in the Cincinnati area are formally named in stratigraphic order: (1) the Brent Sequence, comprising the Edenian Kope Formation; (2) the Riedlin Sequence comprising the Maysvillian Fairview, Miamitown and Bellevue formations; and (3) the Stonelick Sequence comprising the Maysvillian Corryville and Mt Auburn formations. A detailed study of the Riedlin Sequence in outcrops, cores and well logs between Cincinnati, Ohio, Ft Wayne, Indiana, and Indianapolis, Indiana, (13,000 km$\sp2$), reveals stacking patterns within the Riedlin Sequence that are comparable to those of a type-2 sequence. This interpretation contrasts with previous interpretations wherein Cincinnatian third- and fourth-order cycles are dominated by highstand systems tracts with thin or absent lowstand and transgressive deposits, or where these cycles are interpreted as parasequences or parasequence sets rather than sequences. The Miamitown Shale provides a testing ground for a new integrated cyclic, lithologic, and quantitative faunal method of correlating meter-scale fifth-order cycles. This has been accomplished within the 12 m interval surrounding the Miamitown Shale in the upper part of the Riedlin Sequence. First, using lithologic criteria alone, six shale-to-limestone cycles bounded by flooding surfaces were delineated and correlated between seven 12 m outcrop sections within a 30 km radius. Unusual fossil occurrences constrained correlations of cycles 3 & 4, and the presence of a dalmanellid, Heterorthina fairmountensis, showed that the flooding surface above cycle 3 lay 10 cm below the lithologic contact. Quantitatively-defined faunal clusters constrained correlations between all cycles, and revealed a major transition at the top of cycle 2, again below the lithologic contact. Finally, depth gradient fluctuations interpreted from ordination of faunal data suggest that the major transition at the top of cycle 2 is a transgressive surface, and that the middle part of cycle 3 includes the interval of maximum depth.
Filtration theory was developed by engineers to model the removal of particulate matter from industrial gases. Recently, it has been used by biologists and paleo-biologists to model the capture of food particles by filter feeding organisms. The purpose of this study was to test paleosynecologic (biofacies-level) and paleoautecologic (species-level) models of crinoid distribution utilizing filtration theory. These models were tested by analyzing the crinoid faunas of three transgressive-regressive sequences from the Upper Pennsylvanian Lansing Group of midcontinent North America.
Stratigraphic, sedimentologic and petrographic studies of the Lower and Upper Cretaceous in northwest Sonora show that deposition of the Bisbee Group occurred at the northern margin of a back-arc marine basin, and of the El Chanate Group and El Charro volcanic complex in a closed continental foreland basin. This study also finds that the Proterozoic-Paleozoic formations in northwest Sonora (Caborca terrane) were not part of the Cretaceous landscape, thus raising doubts about the existence of the Mojave-Sonora megashear.
Stylolites in twelve stratigraphic sections of the Salem Limestone, distributed throughout the Illinois Basin, provide clues to their origin and development. Chemical and X-ray diffraction analyses reveal that stylolite seam material contains organic matter and clay minerals too sparse or absent in the host limestone to be considered solely as insoluble residue. Stylolite distribution in various lithofacies suggests that stylolites develop along thin sedimentary layers rich in organic matter and clay minerals. Stylolite density (vertical distribution) mimics the distribution of organic-rich sedimentary layers: sparse but thick in grainstone, and abundant but thin in packstone and wackestone. Many stylolites grade laterally into organic-rich layers, or hummocky seams. Thicknesses of stylolite caps and hummocky seams are approximately equal in the same host rock, but hummocky seams tend to be more laterally continuous. Stylolite density in packstone increases with burial depth, whereas hummocky seam density decreases. Hummocky seam thickness does not change with depth. Stylolite column height in grainstone, which is sparse in hummocky seams, increases with depth, whereas stylolite density does not increase. This list of observations supports the hypothesis that stylolites develop along pre-existing, organic-rich layers, or hummocky seams, rather than nucleating in pure host rock and creating organic-rich seams as accumulations of insoluble residue. Volumetric calculations indicate that the contribution of stylolites to pore-filling cement is 5 to 25 percent throughout the Illinois Basin.