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1994

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Articles 1 - 30 of 2008

Full-Text Articles in Life Sciences

Effects Of 17Β-Estradiol On Distribution Of Pituitary Isoforms Of Luteinizing Hormone And Follicle-Stimulating Hormone During The Follicular Phase Of The Bovine Estrous Cycle, F. N. Kojima, Andrea S. Cupp, T. T. Stumpf, D. D. Zalesky, M. S. Roberson, L. A. Werth, M. W. Wolfe, Roger J. Kittok, H. E. Grotjan, J. E. Kinder Dec 1994

Effects Of 17Β-Estradiol On Distribution Of Pituitary Isoforms Of Luteinizing Hormone And Follicle-Stimulating Hormone During The Follicular Phase Of The Bovine Estrous Cycle, F. N. Kojima, Andrea S. Cupp, T. T. Stumpf, D. D. Zalesky, M. S. Roberson, L. A. Werth, M. W. Wolfe, Roger J. Kittok, H. E. Grotjan, J. E. Kinder

Faculty Papers and Publications in Animal Science

The objective of this study was to examine the influence of 17β-estradiol (E2) on distribution of LH and FSH isoforms during the follicular phase of the bovine estrous cycle prior to the preovulatory surges of LH and FSH. On Day 16 of the estrous cycle (Day 0 = estrus), intact controls (CONT; n = 4) were treated with prostaglandin F (PGF) to induce luteal regression and initiation of the follicular phase. Other cows were also treated with PGF and either ovariectomized (OVX; n = 5) or ovariectomized and given E2 implants (OVXE; n = 6) to mimic the pattern ...


Changes In Plant Variety Protection, Neil Harl Dec 1994

Changes In Plant Variety Protection, Neil Harl

Agricultural Law Digest

Since enactment in 1970, the Plant Variety Protection Act had received relatively little attention until the litigation relating to the "saved seed" exception commenced in 1991. That case, Asgrow Seed Co. v. Winterboer, is before the U.S. Supreme Court with a decision expected some time in 1995.

The Congress has now passed and the President has signed legislation amending the 1970 act which reverses, statutorily, the U.S. Court of Appeals decision in Asgrow Seed Co. v. Winterboer and makes several other changes in the Plant Variety Protection Act.


Cases, Regulations And Statutes, Robert P. Achenbach Jr. Dec 1994

Cases, Regulations And Statutes, Robert P. Achenbach Jr.

Agricultural Law Digest

No abstract provided.


Strain Relaxation In Compositionally Graded Ingaas/Gaas Heterostructures, Karen L. Kavanagh, Rachel S. Goldman, Jessica C. P. Chang Dec 1994

Strain Relaxation In Compositionally Graded Ingaas/Gaas Heterostructures, Karen L. Kavanagh, Rachel S. Goldman, Jessica C. P. Chang

Scanning Microscopy

Epilayer strain relaxation in the InGaAs/GaAs system occurs via two mechanisms, plastic deformation and/or surface roughening. Under conditions of two-dimensional growth, we find that compositionally graded InGaAs/GaAs (001) multi-layer buffer structures will plastically deform with < 110 > misfit dislocations approaching 100% strain relaxation. At higher growth temperatures, large-amplitude roughening is observed preferentially along the [110] direction, and the strain relaxation becomes asymmetric in the < 110 > directions. In single epilayers, the symmetry of the strain relaxation is dependent on the magnitude of the substrate offcut angle. In all cases, the epilayers develop a tilt about an in-plane axis in proportion to ...


Atomic Step Organization In Homoepitaxial Growth On Gaas(111)B Substrates, Leo J. Schowalter, Kai Yang, Thomas Thundat Dec 1994

Atomic Step Organization In Homoepitaxial Growth On Gaas(111)B Substrates, Leo J. Schowalter, Kai Yang, Thomas Thundat

Scanning Microscopy

When homoepitaxial growth is performed on exactly oriented (singular) (111) GaAs substrates, while maintaining the √19 x √19 surface reconstruction, the originally flat surface spontaneously evolves vicinal (111) facets that are tilted approximately 2.5° toward the < 211 > azimuthal directions. These facets form pyramid-like structures where the distance between adjacent peaks can be varied from as little as 1 μm to tens of μm. When these surfaces are observed with atomic force microscopy (AFM), we find that they are extremely smooth with the observed tilt resulting from atomic steps which are spaced at approximately 7.5 nm. We have also studied ...


Strain Relaxation In Graded Ingaas And Inp Buffer Layers On Gaas (001), K. Eberl, K. Häusler, T. Shitara, Y. Kershaw, W. Sigle Dec 1994

Strain Relaxation In Graded Ingaas And Inp Buffer Layers On Gaas (001), K. Eberl, K. Häusler, T. Shitara, Y. Kershaw, W. Sigle

Scanning Microscopy

We investigate compositionally graded Inxo≤x≤0.5Ga1-xAs and InP buffer layers which are prepared by molecular beam epitaxy on (001) GaAs substrate. The initial In content xo is equal to 0, 0.12, 0.18, 0.24, and 0.5 for the different samples. The In composition of the graded buffer increases linearly between xo and 0.5 with a fixed slope of 50% In-content per μm. The idea was to combine the advantage of surface flatness in homogeneous buffer layers and the reduced density of threading dislocations on the surface for graded ...


Transmission Electron Microscopy, High Resolution X-Ray Diffraction And Rutherford Backscattering Study Of Strain Release In Ingaas/Gaas Buffer Layers, G. Salviati, L. Lazzarini, C. Ferrari, P. Franzosi, S. Milita, F. Romanato, M. Berti, M. Mazzer, A. V. Drigo, M. R. Bruni, M. G. Simeone, N. Gambacorti Dec 1994

Transmission Electron Microscopy, High Resolution X-Ray Diffraction And Rutherford Backscattering Study Of Strain Release In Ingaas/Gaas Buffer Layers, G. Salviati, L. Lazzarini, C. Ferrari, P. Franzosi, S. Milita, F. Romanato, M. Berti, M. Mazzer, A. V. Drigo, M. R. Bruni, M. G. Simeone, N. Gambacorti

Scanning Microscopy

Strain release and dislocation distribution in InGaAs/GaAs double heterostructures, step-graded and linear-graded buffer layers have been studied. A higher misfit dislocation density at the inner interface between the InGaAs layer and the substrate was found in all the samples. This corresponded to a strain release of the inner ternary layers much larger than predicted by equilibrium theories. The residual parallel strain of the external layers as a function of their thickness was found to follow a curve approximately of slope -0.5, in agreement with previous investigations on single InGaAs layers. This result has been interpreted as evidence that ...


Reconstructions Of C60 On The Ag(111)1x1 Surface, X. -D. Wang, S. Yamazaki, J. -L. Li, T. Hashizume, H. Shinohara, T. Sakurai Dec 1994

Reconstructions Of C60 On The Ag(111)1x1 Surface, X. -D. Wang, S. Yamazaki, J. -L. Li, T. Hashizume, H. Shinohara, T. Sakurai

Scanning Microscopy

We report the scanning tunneling microscope (STM) study of the C60 adsorption on the Ag(111)1x1 surface. The well-ordered C60 monolayer with good quality was obtained by briefly annealing the multilayer C60 at approximately 300°C. It is concluded that the (23)x(23)R30° reconstruction is energetically the most stable phase, while two other phases, "hex-a" and "hex-b" phases, are also observed, rotated by approximately 12.5 ± 1.5° and 47.5 ± 1.5° with respect to the stable (23)x(23)R30° phase. It is suggested that some specific stable ...


Bias Dependence Of The Depletion Layer Width In Semi-Insulating Gaas By Charge Collection Scanning Microscopy, A. Castaldini, A. Cavallini, C. Del Papa, M. Alietti, C. Canali, F. Nava, C. Lanzieri Dec 1994

Bias Dependence Of The Depletion Layer Width In Semi-Insulating Gaas By Charge Collection Scanning Microscopy, A. Castaldini, A. Cavallini, C. Del Papa, M. Alietti, C. Canali, F. Nava, C. Lanzieri

Scanning Microscopy

A procedure for the evaluation of the depletion region width of a Schottky barrier diode made on semi-insulating materials has been assessed and applied to gallium arsenide nuclear detectors. This procedure, which makes use of the optical beam induced current method of charge collection scanning microscopy, allows the direct measurement of the depletion layer width. By taking into account the high resistivity of the material under examination and measuring the diode reverse current, it is possible to evaluate the actual voltage applied at the depletion layer boundaries. It was found that, at low actual bias values, the voltage dependence of ...


Principles Of Semiconductor Surface Reconstruction, C. B. Duke Dec 1994

Principles Of Semiconductor Surface Reconstruction, C. B. Duke

Scanning Microscopy

Semiconductor surfaces are known to reconstruct, i.e., their surface atomic geometries differ from those of the corresponding surface planes in the bulk material. For clean tetrahedrally coordinated semiconductors, these reconstructed geometries are shown to be predicted by five simple principles. These principles are illustrated by the specific examples of Si(100)-(2x1), Si(111)-(2x1), GaAs(100)-c(2x8), GaAs(111)-(2x2), and relaxed zincblende (110) surfaces. The concept of universal (i.e., material independent) semiconductor surface structures is introduced and shown to be characteristic of the cleavage surfaces of tetrahedrally coordinated compound semiconductors. The role of scanning tunneling ...


Mapping Metal Distributions In Thin Cryosections Without Scanning Transmission Electron Microscope With The Philips Electron Beam And Image Deflection (Ebid) Unit, A. J. Morgan, J. M. Brock, C. Winters, G. H. J. Lewis Dec 1994

Mapping Metal Distributions In Thin Cryosections Without Scanning Transmission Electron Microscope With The Philips Electron Beam And Image Deflection (Ebid) Unit, A. J. Morgan, J. M. Brock, C. Winters, G. H. J. Lewis

Scanning Microscopy

The purpose of the present paper was to describe the use of a commercially-available, and relatively inexpensive, beam and image deflection unit that can facilitate digital X-ray (element) mapping in a standard transmission electron microscope not furnished with a STEM attachment. The test specimen was a thin freeze-dried section of the metal-sequestering chloragogenous tissue from the earthworm, Lumbricus rubellus, inhabiting a soil naturally contaminated with Pb, Zn and Cd. Qualitative maps obtained from this material confirmed the efficacy of the deflection unit, and revealed the presence of three compositionally distinct metal-accumulating compartments within the chloragocytes: (i) ovoid, electron-dense, phosphate-bearing and ...


Role Of Surface Interactions In Determining Surface Structure And State Formation In Iii-V Semiconductors, H. E. Ruda, G. P. Jiang Dec 1994

Role Of Surface Interactions In Determining Surface Structure And State Formation In Iii-V Semiconductors, H. E. Ruda, G. P. Jiang

Scanning Microscopy

GaAs(100), (110), and (111) surfaces are chosen as a vehicle to explain the plethora of surface relaxation and reconstruction phenomena seen for III-V compound semiconductors. These relaxation and reconstruction processes directly affect the formation of surface states. The occupation of these states, in turn, can have a profound influence on device performance. The purpose of this work is to attempt to provide a unified description of the phenomena responsible for surface relaxation and reconstruction on these surfaces. Our work makes use of an ab initio effective core potential scheme based on the Hartree Fock approximation. We discuss the critical ...


Surface Stress, Morphological Development, And Dislocation Nucleation During Sixge1-X Epitaxy, D. E. Jesson, S. J. Pennycook, J. -M. Baribeau, D. C. Houghton Dec 1994

Surface Stress, Morphological Development, And Dislocation Nucleation During Sixge1-X Epitaxy, D. E. Jesson, S. J. Pennycook, J. -M. Baribeau, D. C. Houghton

Scanning Microscopy

Utilizing Ge marker layer experiments combined with atomic number contrast (Z-contrast) imaging, we have studied the evolving surface morphology of SixGe1-x alloys during growth by molecular beam epitaxy. The marker layers map out the instability transition between planar two-dimensional (2D) growth and three-dimensional (3D) growth. The transition occurs via the gradual formation of a surface ripple as anticipated from instability theory. However, these undulations rapidly develop into crack-like surface instabilities which we simulate and explain by the mechanism of stress-driven surface diffusion. Finally, we model the large stresses associated with these features within a fracture mechanics formalism ...


Dislocation Nucleation And Propagation In Semiconductor Heterostructures, D. Cherns, S. Mylonas, C. T. Chou, J. Wu, D. E. Ashenford, B. Lunn Dec 1994

Dislocation Nucleation And Propagation In Semiconductor Heterostructures, D. Cherns, S. Mylonas, C. T. Chou, J. Wu, D. E. Ashenford, B. Lunn

Scanning Microscopy

This paper considers misfit dislocation nucleation and propagation in dilute magnetic semiconductor heterostructures in the CdTe-ZnTe-MnTe system. It is shown that, where the deposit is in tension, 1/2 < 110 > dislocations with inclined Burgers vectors propagate by glide along interfacial < 110 > directions and may dissociate giving intrinsic stacking faults. In cases where the deposit is in compression, 1/2 < 110 > dislocations show no evidence of dissociation and propagate by extensive cross-slip to give networks of dislocations close to interfacial < 100 > directions.

Evidence for dislocation sources in ZnTe/GaSb films is presented. ZnTe films contained stacking fault pyramids, single Frank faults and a new type ...


Light Scattering And Electron Microscopy Study Of The Surface Morphology Of Gaas Films Grown By Molecular Beam Epitaxy, M. K. Nissen, C. Lavoie, S. Eisebitt, T. Pinnington, T. Tiedje Dec 1994

Light Scattering And Electron Microscopy Study Of The Surface Morphology Of Gaas Films Grown By Molecular Beam Epitaxy, M. K. Nissen, C. Lavoie, S. Eisebitt, T. Pinnington, T. Tiedje

Scanning Microscopy

The surface morphology of thermally quenched GaAs films grown by molecular beam epitaxy on GaAs substrates has been studied by elastic light scattering, by scanning electron microscopy and by scanning tunneling microscopy (STM) in air. STM shows that the oxide-desorbed surface of GaAs is pitted, but smooths after deposition of a few hundred nanometers of material. Light scattering shows that, after the surface has smoothed, the power spectral density of the surface approaches a q-2 dependence on spatial frequency over the spatial frequency range 0.2 μm-1 < q < 20 μm-1 that is accessible to the light scattering measurements at 488 ...


Ionoluminescence: A New Tool For Nuclear Microprobes In Geology, C. Yang, N. P. -O. Homman, K. G. Malmqvist, L. Johansson, N. M. Halden, V. Barbin Dec 1994

Ionoluminescence: A New Tool For Nuclear Microprobes In Geology, C. Yang, N. P. -O. Homman, K. G. Malmqvist, L. Johansson, N. M. Halden, V. Barbin

Scanning Microscopy

When an ion beam in the energy range of a few MeV/amu impacts on a mineral, visible light can often be observed. This light, induced by energetic ions, is termed ionoluminescence (IL). The intensity and wavelength of the ionoluminescent light provide information concerning the nature of luminescence centers, such as trace substituents and structural defects, found in the mineral. This makes IL a useful complement to other methods of ion beam analysis (IBA), such as particle induced X-ray emission (PIXE) and Rutherford backscattering (RBS), in characterizing geological samples. In the present study, a proton or alpha particle beam was ...


The Morphology And Misfit Dislocation Formation Characteristics Of Strained Heteroepitaxial Layers: Ex Situ And In Situ Growth Studies, A. G. Cullis Dec 1994

The Morphology And Misfit Dislocation Formation Characteristics Of Strained Heteroepitaxial Layers: Ex Situ And In Situ Growth Studies, A. G. Cullis

Scanning Microscopy

Under certain regimes of heteroepitaxial layer growth, misfit stresses can lead to very significant distortions in interface morphology, which can influence strain relief and subsequent misfit dislocation introduction. These phenomena have been clearly demonstrated in the case of SiGe/Si heteroepitaxy and the way in which surface SiGe growth ripples are accompanied by strain waves has been established. The ripples provide partial elastic relief of the layer misfit stress in a manner which has been correlated with theoretical expectations. The local stress variations ultimately may influence the formation and disposition of misfit dislocations in the strained layer structures. The present ...


Ultrastructure Of Dentin Matrix In Heritable Dentin Defects, J. Waltimo, H. Ranta, P. -L. Lukinmaa Dec 1994

Ultrastructure Of Dentin Matrix In Heritable Dentin Defects, J. Waltimo, H. Ranta, P. -L. Lukinmaa

Scanning Microscopy

Heritable dentin defects form a group of diseases which exclusively affect dentin among the various dental tissues. While one type is associated with the generalized connective tissue disorder, osteogenesis imperfecta, other types occur as single traits. The clinical manifestations of the dentin defects vary from insignificant to severe enough to cause aesthetical and functional failure of the teeth. Scanning and transmission electron microscopic studies, reviewed in this paper, have markedly clarified the ultrastructure of the aberrant dentin matrix. Both similar and different changes seem to occur in the various forms of heritable dentin defects. Abnormalities in the appearance and organization ...


Metastable Reconstructions On Si(111), Y. -N. Yang, E. D. Williams Dec 1994

Metastable Reconstructions On Si(111), Y. -N. Yang, E. D. Williams

Scanning Microscopy

We report unambiguous atomic scale evidence demonstrating that the atom density in the high temperature "1x1" phase of Si(111) is ~6% higher than the 7x7. Such evidence is provided by scanning tunneling microscopy (STM) observation of excess adatom density, and related island formation, on surfaces with very large terraces. The unusually large terraces were produced by heating the sample with DC current in the step-down direction at 1200°C. By trapping adatoms on the terraces through a quench, we have also created areas of metastable reconstructions, i.e., 9x9, 2x2, c2x4 and 3x3, much larger than previously reported ...


Boron Reconstructed Si(111) Surfaces Produced By B2o3 Decomposition, J. Nogami, S. Yoshikawa, J. C. Glueckstein, P. Pianetta Dec 1994

Boron Reconstructed Si(111) Surfaces Produced By B2o3 Decomposition, J. Nogami, S. Yoshikawa, J. C. Glueckstein, P. Pianetta

Scanning Microscopy

Scanning tunneling microscopy has been used to study the growth of boron on the Si(111) surface. Boron was deposited in the form of B2O3 which was decomposed by heating the substrate. With this technique, it is possible to control the B coverage, and also to produce the well known 3 x 3 reconstruction at annealing temperatures as low as 600°C. The optimal conditions for the formation of the 3 x 3 surface by B2O3 decomposition are given. In addition, the nature of the 3 x 3 surface over a range of B ...


Observations On Interactions Between Metal Clusters And Iii-V Semiconductor Substrates, Theodore D. Lowes Dec 1994

Observations On Interactions Between Metal Clusters And Iii-V Semiconductor Substrates, Theodore D. Lowes

Scanning Microscopy

Interfacial reactions between deposited indium and gallium metals with GaAs(001) substrates are discussed. After Knudsen cell molecular beam epitaxy (MBE) deposition, samples were annealed in ultrahigh vacuum (UHV) and examined by ex situ electron microscopy. The resulting microstructure was compared to the microstructure of GaAs(001) substrates without metal deposition. It is shown that significant interactions occur between the deposited metal and substrate and that the final microstructure is consistent with the model for thermal decomposition of III-V compound semiconductor substrates.


Reflection High Energy Electron Diffraction (Rheed) Intensity Oscillations: Growth Modes And Growth Rates: A Critique, B. A. Joyce, X. M. Zhang, J. H. Neave, P. N. Fawcett, M. R. Fahy, K. Sato, I. Kamiya Dec 1994

Reflection High Energy Electron Diffraction (Rheed) Intensity Oscillations: Growth Modes And Growth Rates: A Critique, B. A. Joyce, X. M. Zhang, J. H. Neave, P. N. Fawcett, M. R. Fahy, K. Sato, I. Kamiya

Scanning Microscopy

The origin of and diffraction effects associated with reflection high energy electron diffraction (RHEED) intensity oscillations which occur during layer-by-layer growth of epitaxial thin films of III-V compounds by molecular beam epitaxy (MBE) are explained. It is shown that on (001) oriented substrates the period of the oscillations is in general a direct measure of the film growth rate which corresponds to the group III element flux. There are, however, exceptions to this simple concept including growth under group III rich-conditions, vicinal plane growth and growth from pulsed beams; each is considered.

On non-(001) low index orientations, the RHEED ...


Microdissection And Measurement Of Polytene Chromosomes Using The Atomic Force Microscope, Curtis Mosher, Daniel Jondle, Linda Ambrosio, James Vesenka, Eric Henderson Dec 1994

Microdissection And Measurement Of Polytene Chromosomes Using The Atomic Force Microscope, Curtis Mosher, Daniel Jondle, Linda Ambrosio, James Vesenka, Eric Henderson

Scanning Microscopy

A method to isolate specific regions of the Drosophila polytene chromosome using an atomic force microscope (AFM) was explored. The AFM was used for the microdissection of the locus of interest with much greater precision than standard microdissection techniques. The amplification of DNA isolated in this fashion by the polymerase chain reaction (PCR) is discussed. A study of the effect of hydration level on gross chromosome structure was carried out. It was shown that chromosome swelling is dependent upon humidity or the buffered medium. The significance of this swelling with respect to studies of chromosome structure under physiological conditions is ...


Epitaxial Growth Studies By Low Energy Electron Microscopy, E. Bauer Dec 1994

Epitaxial Growth Studies By Low Energy Electron Microscopy, E. Bauer

Scanning Microscopy

In spite of being a surface sensitive tool, low energy electron microscopy (LEEM) can also give information on interfaces. An example is the CoSi2/Si(111) interface. Most of the work discussed in this paper, however, makes use of the high surface sensitivity of LEEM which makes this method an ideal tool for the study of the early growth stages in epitaxy, in particular of the growth dynamics and of the influence of misfit on the growth mode. Two prototype substrates, Mo(110) and Si(111), and three representative deposit metals, Cu, Au and Co, are used to illustrate ...


Meeting Minutes, December 20th, 1994, National Smokejumper Association Executive Committee Dec 1994

Meeting Minutes, December 20th, 1994, National Smokejumper Association Executive Committee

National Smokejumper Association Meeting Minutes

Agenda: Old Business; Board Walk Travel; Travel From Washington Dc To Missoula; Ronald Young National Agriculture Library; Hotel/Motel; Camping At Fairgrounds. Restrooms Open?; Day Trips; News Letter; Motels, Car Rental, Airlines, And Listing Of Day Trips; Work Study Student; Membership Rosters; Rent Vs Direct Payment; Nsa To Pay Earl; Reunion; Planning Meetings; Invite Charter;


The Principles Of Proton Probe Microanalysis In Biology, G. J. F. Legge, M. Cholewa Dec 1994

The Principles Of Proton Probe Microanalysis In Biology, G. J. F. Legge, M. Cholewa

Scanning Microscopy

The proton microprobe, more correctly described as an ion microprobe which operates at MeV energies, complements its parent instrument the electron microprobe. This paper compares the basic principles and performance of the two instruments and relates the evolution of biological analysis on such ion microprobes to that on electron microprobes, covering the development of sample handling techniques and of data handling techniques and comparing beam damage studies. The paper describes the variety of techniques available to the ion microprobe - the initial techniques of Energy Dispersive X-ray analysis, Rutherford Back Scattering and Nuclear Reaction Analysis and the rapid evolution of new ...


X-Ray Absorption Studies Of Strain In Epitaxial (Si-Ge) Atomic Layer Superlattice And Alloy Films, T. Tyliszczak, A. P. Hitchcock, Z. H. Lu, J. -M. Baribeau, T. E. Jackman Dec 1994

X-Ray Absorption Studies Of Strain In Epitaxial (Si-Ge) Atomic Layer Superlattice And Alloy Films, T. Tyliszczak, A. P. Hitchcock, Z. H. Lu, J. -M. Baribeau, T. E. Jackman

Scanning Microscopy

The Si 1s (K-shell) X-ray absorption spectra of a series of strained SixGe100-x alloy thin films and several {(Si)m(Ge)n}p atomic layer superlattices (ALS) grown epitaxially on Si(100) and Ge(100) substrates have been investigated using plane polarized synchrotron radiation. Polarization dependent components of the signal are attributed to anisotropic states associated with strain-induced tetragonal distortions. The sense of the polarization is shown to be identical for all compositions (x = 25 to 92) of SiGe alloys grown on Si(100) substrates. The opposite polarization dependence is found to occur for all Six ...


Interfacial Studies In Semiconductor Heterostructures By X-Ray Diffraction Techniques, J. -M. Baribeau, R. L. Headrick, P. Maigné Dec 1994

Interfacial Studies In Semiconductor Heterostructures By X-Ray Diffraction Techniques, J. -M. Baribeau, R. L. Headrick, P. Maigné

Scanning Microscopy

X-ray radiation is a non-destructive probe well suited to assess structural perfection of semiconductor material. Three techniques are used to study the interfacial roughness, period fluctuations and annealing-induced interdiffusion in various superlattice structures. Reflectivity of long period Si/Si1-xGex multiple quantum wells reveals an asymmetry oriented along the direction of miscut in the interface roughness with the Si1-xGex to Si interfaces being about twice as rough (0.5 versus 0.3 nm) as the Si to Si1-xGex interfaces. For Si-Si0.65Ge0.35 multiple quantum wells, diffuse scattering is ...


Cropwatch No. 94-24-2, Dec. 16, 1994, Lisa Brown Jasa Dec 1994

Cropwatch No. 94-24-2, Dec. 16, 1994, Lisa Brown Jasa

Crop Watch

Inside

1994 index .......................... 164

Grants for producers .......... 166

CropWatch order form........ 167

Annual survey .................... 167


Agricultural And Food Policy Preferences: The 1994 Perspectives Of South Dakota Agricultural Producers, Bashir Qasmi, John A. Sondey Dec 1994

Agricultural And Food Policy Preferences: The 1994 Perspectives Of South Dakota Agricultural Producers, Bashir Qasmi, John A. Sondey

Economics Research Reports

U.S. farm policies are reviewed, every five years concurrent with the drafting of new farm legislation. The present farm bill expires in 1995, and a new bill will be debated and enacted in 1995. Since farm and food policies have a major impact on farmers, information on their preferences with regard to these policies are invaluable to legislators as well as to different advocacy groups (working for farmers). The research was completed as a part of a 15 state study to document the agricultural and food policy preferences by agricultural producers. This report deals with the policy preferences of ...