bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Neutron Bombardment Reduction of Transistor Current Gain
Authors: Easley J. W. , Dooley J. A. 
Published: April 2005

Detailed measurements of the fast-neutron and gamma-ray bombardment behavior of germanium-alloy-transistor current-gain have been obtained concurrent with exposure. These data indicate that previously reported analyses, which lead to a linear dependence of common-base current-gain on fast neutron exposure, yield a good approximation for the npn device, but are not of general validity for the pnp germanium transistor. The extent of departure from the linear approximation depends on the width and conductivity of the base-region and can be appreciable in many cases of practical interest.For the pnp germanium transistor it is necessary to take additional account of both changes during bombardment of the minority-carrier recombination rate at bombardment introduced and initially present recombination centers and changes in the width of the collector junction depletion layer. Observed bombardment curves are in good agreement with an analysis which includes these effects. From initial slopes of the current-gain bombardment curves, values of the product of fast-neutron-exposure times minority-carrier-lifetime at bombardment introduced recombination centers are 9.7×107 for 2.7 ohm-cm p-type and 14.2×107, 6.0×107, and 1.3×107, for 3.6 ohm-cm, 1.2 ohm-cm, and 0.2 ohm-cm n-type germanium, respectively, in units of sec-neutrons/cm2.
Simple Radiant Heating Method for Determining the Thermal Diffusivity of Cellulosic Materials
Authors: Martin Stanley B. 
Published: April 2005

A simple radiometric method for the determination of the thermal diffusivity of poorly conducting sheet-form materials such as cellulosic kindling fuels is described. The method is a dynamic one based on the ``long time'' solution of the heat-conduction equation for the infinite slab with constant heat-input rate, and utilizes fine-wire thermocouples laminated between sheets of the material (whose diffusivity is required) to measure rates of temperature rise at various depths. The geometry of the system is designed to satisfy as many as possible of the boundary conditions imposed on the mathematical model. The magnitude of errors introduced by violating the other boundary conditions is discussed in connection with the results of measurements on α-cellulose.
The value of the thermal diffusivity of α-cellulose containing two percent carbon black and whose density is 0.68 g/cm3 was found to be 1.06±0.06×10−3 cm2/sec.
Transport of Noise at Microwave Frequencies through a Space-Charge-Limited Diode
Authors: Vivian W. E. 
Published: April 2005

Several analyses of the transport of cathode shot noise through a space-charge-limited diode at microwave frequencies have been published to date. Each of these analyses has been beset by inconsistencies arising from assumptions of monovelocity perturbation flow, direct or reflected. A new method of analysis of diode flow eliminating this problem has been developed. Numerical results based on this method are presented here. Attention is restricted to the now classical problem of one-dimensional longitudinal confined flow.
The magnitude and variation with distance of the so-called beam noise invariants is shown for a range of diode operating conditions. These calculated results, based for economy on an approximate static flow model, essentially substantiate the qualitative expectations suggested by prior analyses, and fit what little experimental data are available.
The method of analysis employed in the calculation of the numerical results comprises a linear multistream formulation, based on representation or approximation of the perturbation particle density for the noise flow as a composite of singular impulse streams, N in number, along characteristic trajectories in the velocity-distance phase space. The set of N coupled first-order linear differential equations resulting is solved by simultaneous numerical extrapolation.
Power Flow and Stored Energy in Thin Electron Beams
Authors: Rigrod W. W. 
Published: April 2005

The kinetic and electromagnetic components of ac power and stored energy are evaluated for space-charge waves along thin drifting beams of simple geometry. It is found that: (a) when a modulated beam is decelerated, it radiates power into the surrounding space; (b) when both fast and slow waves are excited by a common source, the real kinetic power varies periodically with distance, exchanging energy with the electromagnetic field; and (c) when a finite-area beam is current modulated with zero ac velocity, the total power need not be zero.The energy transport velocity of a space-charge wave is shown to equal its group velocity, when the time-average stored energy is properly evaluated. A small portion of the stored kinetic energy propagates, together with the field energy, as an electromechanical wave along the beam. The larger part of the kinetic energy, which can be positive or negative, is transported by the motion of the beam itself.
Uniform Silicon p-n Junctions. II. Ionization Rates for Electrons
Authors: Chynoweth A. G. 
Published: April 2005

Charge multiplication as a function of reverse bias has been studied in a number of uniform silicon p-n junctions (junctions free from defects which promote local avalanche breakdown sites). From the multiplication characteristics new data have been derived for the field dependence of the ionization rate (α) for electrons. As previously found in junctions containing dislocations, α obeys the empirical relation α=α∞ exp (−b/E), where α∞ and b are constants and E is the field. Thus, this law is not simply a consequence of distortions to the junction introduced by dislocations or other microplasma-inducing defects.
The ionization rates and breakdown voltages for the uniform junctions can be made consistent with older data (for nonuniform junctions) if the junction fields, as determined from capacitance measurements, in the new junctions are multiplied by 0.65. The most obvious interpretation of this experimental fact is that breakdown is made relatively easier at defects because the field is actually higher by a factor of 1.55. Possible causes of such an enhancement are discussed together with alternative hypotheses for the different ionization rates.
On the Kinetics and Mechanism of the Precipitation of Lithium from Germanium
Authors: Carter J. R. , Swalin R. A. 
Published: April 2005

The kinetics of precipitation of lithium from germanium have been investigated and the following variables have been studied: (a) crystal source; (b) preannealing treatments prior to the introduction of lithium; (c) the effect of selective impurity additions, namely, oxygen and copper. The precipitation process can be described as following the law given below: logC/C0=exp[−(t/τ)n].
Upon saturation at elevated temperatures, (about 425°C), n is found to be 32 for the first part of the process and 1 for the later part of the process. Upon saturation at low temperatures, however, n is found to be ½. It is suggested that this results from the nonuniform distribution of lithium in the crystal prior to precipitation.
Nucleus number densities varying by orders of magnitude were obtained from different crystals. It was found that a preannealing treatment at 900°C was sufficient to increase the nuclei number densities for all crystals and the differences tend to disappear upon the preannealing treatment.
Doping with oxygen tended to increase very markedly the number density of nuclei whereas doping with small amounts of copper (several orders of magnitude less than lithium present) decreased the number density of nuclei by about an order of magnitude. Interpretation of these results suggests that an impurity, consisting either of particles or oxygen-vacancy pairs, is catalyzing the precipitation process.
Beam Refrigeration by Means of Large Magnetic Fields
Authors: Adler Robert , Wade Glen 
Published: April 2005

The resistive loading which an electron beam produces in an adjacent structure can be made to exhibit a very low noise temperature. This is achieved by coupling to the fast cyclotron wave in a large magnetic field; the noise temperature at a given signal frequency is shown to be equal to the cathode temperature times the ratio of signal frequency to cyclotron frequency.An experiment is described in which this ratio is 19. The coupling structure interacts with the fast cyclotron wave but rejects the slow cyclotron wave. A noise temperature of 186°K is measured.In conclusion, it is shown that the large magnetic field required for beam cooling need not extend throughout the tube.
Low-Temperature Transport Properties of Commercial Metals and Alloys. IV. Reactor Grade Be, Mo, and W
Authors: Powell Robert L. , Harden James L. , Gibson Edward F. 
Published: April 2005

The thermal conductivity, electrical resistivity, Lorenz ratio, and thermoelectric power are given in the temperature range 4°–120°K for four reactor grade metals: beryllium with sample axis parallel to the pressing axis, beryllium with sample axis perpendicular to the pressing axis, molybdenum, and tungsten, the latter two doped with ThO2. Within the given temperature range the molybdenum and tungsten show slight maxima in thermal conductivity, the beryllium does not. The various components of the electronic and lattice thermal conductivities and resistivities are resolved. The residual electrical resistivities are, respectively, 0.64, 1.01, 0.57, and 0.16×10−6 ohm-cm.
The Lorenz ratios for molybdenum and tungsten show both maxima and minima and are always below the Sommerfeld value. The ratios for the beryllium samples have broad maxima and generally are above the Sommerfeld value. The thermoelectric powers of the samples with respect to pure copper are negative for the higher temperatures and positive for the lower temperatures.
Microwave Properties of Nonstoichiometric Polycrystalline Yttrium Iron Garnet
Authors: Seiden P. E. , Kooi C. F. , Katz J. M. 
Published: April 2005

An investigation has been made of the microwave properties of nonstoichiometric yttrium iron garnet ranging from 31% iron excess through stoichiometric to 12% yttrium excess. No ion substitution in the garnet lattice is observed. All material in excess of stoichiometric proportions goes into ceramic second phases. The phases observed are perovskite (YFeO3) for yttrium excess, hematite (Fe2O3) for iron-excess samples fired in oxidizing atmospheres, and magnetite (Fe3O4) for iron-excess samples fired in neutral atmospheres.
On the basis of the assumption that all excess material goes into the appropriate ceramic second phase, we may account for the behavior of the saturation magnetization, spectroscopic splitting factor, and linewidth as a function of composition.
It is found that the linewidth is strongly narrowed by the large magnetization as predicted by Geschwind and Clogston. The behavior of the dielectric constant can be explained, at least qualitatively, by a theory of Wagner and Sillars which considers particles of one dielectric material imbedded in a matrix of another. The behavior of the dielectric loss tangent is not understood and cannot be accounted for by this theory.
Spiral Dislocations on Glass Fracture Surfaces
Authors: Levengood W. C. , Vong T. S. 
Published: April 2005

Within a certain range of composition spiral defects were observed on etched soda-lime-silica glasses. The patterns described spirals of Archimedes and appeared to originate from interstitial defects in the glass. Mutual stress influence effects were observed. The hypothesis of an existing torque field around the interstitial defects was useful in explaining the spiral mechanism. Application of mechanical torque stresses produced the spiral effect. In some cases it appeared feasible to apply stress energy relationships developed from dislocation theories to these minute flaw patterns.
A dynamic spherical indenter technique was developed to study structural variations in these glasses. The lengths of flaws produced by a rolling indenter were found to be sensitive to changes in the silica content of the glasses and less affected by variations in the soda-lime ratio. The effects of heating and crystallization were also studied.
Plasma Propulsion by a Rapidly Varying Magnetic Field
Authors: Klein Milton M. , Brueckner Keith A. 
Published: April 2005

An investigation has been made of the motion of a plasma under the action of a rapidly varying magnetic field from a stationary coil. The analysis has been done for two cases: (1) the plasma is assumed completely diamagnetic so that the ionization history of the plasma may be ignored and (2) the nondiamagnetic case where the ionization process is considered in detail. For the diamagnetic case the analysis yields a coupled set of nonlinear ordinary differential equations which have been put in similarity form and solved for a wide range of the similarity parameters. An illustrative example is given to show how to use the results to obtain detailed information for a given physical system. The calculations indicate that, for field frequencies of about one megacycle, velocities of the order 107 cm/sec may be attained, but the efficiency of conversion of stored energy into kinetic energy is rather low (about 5–10%) and cannot be varied much by possible changes in the physical and geometrical parameters of the system.
Because of the complexity of the analysis, a systematic series of solutions has not been made for the nondiamagnetic case. Instead, a typical example has been worked out to indicate the major differences to be expected. The results show that the nondiamagnetic plasma yields an efficiency slightly less than that obtained for the corresponding diamagnetic plasma. The ionization process inside the plasma levels off very rapidly so that the electron density increases by only a few percent during the motion of the plasma, but the amount of ionization has very little effect upon the efficiency of the system. The indications are that the efficiency of a plasma driven by a magnetic field from a stationary coil is probably too low for practical applications.
Optical Observations Concerning the Polymorphic Transition in the Potassium Halides
Authors: Wiederhorn S. , Drickamer H. G. 
Published: April 2005

At approximately 20 000 atm the potassium halides undergo a phase transition from the FCC (NaCl) structure to the SC (CsCl) structure. Using optical equipment developed in this laboratory various optical effects were observed including the rate of cutoff of the light and the wavelength dependence of the scattered light. The phase transition is apparently initiated by shear involving a large cutoff of light with little or no volume change. At the beginning and end of the transition the scattering is largely small particle scattering, with large particles dominating the middle region. Rb+ impurity has little effect on the transition. Na+ impurity apparently inhibits the nucleation strongly, and, to some extent, the growth.
From the absorption spectra of Pb++ ion impurity it is apparent the nuclei consist of hundreds of ions, rather than smaller units.
Production of Single-Crystal Copper Films at Low Temperatures
Authors: Yelon Arthur , Hoffman R. W. 
Published: April 2005

A method is described for the production of single-crystal films of copper at temperatures as low as −40°C. This method utilizes the epitaxy of copper on rocksalt. A thin layer of copper is evaporated on a single crystal of salt at 350°C. Then a thick layer is evaporated at the low temperature.
Films grown by this method have been examined using x-ray and etching techniques. It was found that some of these films had single-crystal regions of 1 mm diameter and larger. These crystallites had [100] directions within 1° to a normal to the film surface.
Antisense Suppression of a (+)-δ-Cadinene Synthase Gene in Cotton Prevents the Induction of This Defense Response Gene during Bacterial Blight Infection But Not Its Constitutive Expression
Authors: Townsend Belinda J. , Poole Andrew , Blake Christopher J. , Llewellyn Danny J. 
Published: April 2005

Abstract
In cotton (Gossypium hirsutum) the enzyme (+)-δ-cadinene synthase (CDNS) catalyzes the first committed step in the biosynthesis of cadinane-type sesquiterpenes, such as gossypol, that provide constitutive and inducible protection against pests and diseases. A cotton cDNA clone encoding CDNS (cdn1-C4) was isolated from developing embryos and functionally characterized. Southern analysis showed that CDNS genes belong to a large multigene family, of which five genomic clones were studied, including three pseudogenes and one gene that may represent another subfamily of CDNS. CDNS expression was shown to be induced in cotton infected with either the bacterial blight or verticillium wilt pathogens. Constructs for the constitutive or seed-specific antisense suppression of cdn1-C4 were introduced into cotton by Agrobacterium-mediated transformation. Gossypol levels were not reduced in the seeds of transformants with either construct, nor was the induction of CDNS expression affected in stems of the constitutive antisense plants infected with Verticillium dahliae Kleb. However, the induction of CDNS mRNA and protein in response to bacterial blight infection of cotyledons was completely blocked in the constitutive antisense plants. These results suggest that cdn1-C4 may be involved specifically in the bacterial blight response and that the CDNS multigene family comprises a complex set of genes differing in their temporal and spatial regulation and responsible for different branches of the cotton sesquiterpene pathway.
Cloning and Characterization of GLOSSY1, a Maize Gene Involved in Cuticle Membrane and Wax Production
Authors: Sturaro Monica , Hartings Hans , Schmelzer Elmon , Velasco Riccardo , Salamini Francesco , Motto Mario 
Published: April 2005

Abstract
The cuticle covering the aerial organs of land plants plays a protective role against several biotic and abiotic stresses and, in addition, participates in a variety of plant-insect interactions. Here, we describe the molecular cloning and characterization of the maize (Zea mays) GLOSSY1 (GL1) gene, a component of the pathway leading to cuticular wax biosynthesis in seedling leaves. The genomic and cDNA sequences we isolated differ significantly in length and in most of the coding region from those previously identified. The predicted GL1 protein includes three histidine-rich domains, the landmark of a family of membrane-bound desaturases/hydroxylases, including fatty acid-modifying enzymes. GL1 expression is not restricted to the juvenile developmental stage of the maize plant, pointing to a broader function of the gene product than anticipated on the basis of the mutant phenotype. Indeed, in addition to affecting cuticular wax biosynthesis, gl1 mutations have a pleiotropic effect on epidermis development, altering trichome size and impairing cutin structure. Of the many wax biosynthetic genes identified so far, only a few from Arabidopsis (Arabidopsis thaliana) were found to be essential for normal cutin formation. Among these is WAX2, which shares 62% identity with GL1 at the protein level. In wax2-defective plants, cutin alterations induce postgenital organ fusion. This trait is not displayed by gl1 mutants, suggesting a different role of the maize and Arabidopsis cuticle in plant development.
Identification and Characterization of Endoplasmic Reticulum-Associated Degradation Proteins Differentially Affected by Endoplasmic Reticulum Stress
Authors: Kirst Mariana E. , Meyer David J. , Gibbon Bryan C. , Jung Rudolf , Boston Rebecca S. 
Published: April 2005

Abstract
The disposal of misfolded proteins from the lumen of the endoplasmic reticulum (ER) is one of the quality control mechanisms present in the protein secretory pathway. Through ER-associated degradation, misfolded substrates are targeted to the cytosol where they are degraded by the proteasome. We have identified four maize (Zea mays) Der1-like genes (Zm Derlins) that encode homologs of Der1p, a yeast (Saccharomyces cerevisiae) protein implicated in ER-associated degradation. Zm Derlins are capable of functionally complementing a yeast Der1 deletion mutant. Such complementation indicates that the Der1p function is conserved among species. Zm Derlin genes are expressed at low levels throughout the plant, but appear prevalent in tissues with high activity of secretory protein accumulation, including developing endosperm cells. Expression of three of the four Zm Derlin genes increases during ER stress, with Zm Derlin1-1 showing the strongest induction. Subcellular fractionation experiments localized Zm Derlin proteins to the membrane fraction of microsomes. In maize endosperm, Zm Derlin proteins were found primarily associated with ER-derived protein bodies regardless of the presence of an ER stress response.
The perception of ward‐based nurses seconded into an Outreach Service
Authors: Plowright Catherine , O'Riordan Bernadette , Scott Glyn 
Published: April 2005

AbstractA group of ward nurses were seconded into an Outreach Service for a 2‐week period. Following this, the group took part in an evaluation of the placement using a focus group methodology. The aim of this project was to explore the perceptions of a ward‐based nurse recruited into the Outreach Service so that they could function effectively and efficiently in that role.The intended outcomes of the project were:– to explore the needs of the new Outreach nurse who was recruited from the ward environment– to enable the participants of the project to have a better understanding of the role of the Outreach team– to enable the participants to develop their skills in assessing critically ill patients– to make recommendations to the Kent Critical Care Network regarding the recruitment of ward staff to Outreach
Assessment of practice using the National Health Service Knowledge and Skills Framework
Authors: McLean Christopher , Monger Eloise , Lally Isabella 
Published: April 2005

AbstractCurrent difficulties in the assessment of practice of qualified nurses undertaking courses in critical care nursing are outlined and discussed. The evaluation and development of previously identified core competencies for intensive care nurses is discussed.The use of the National Health Service Knowledge and Skills Framework as a framework for the assessment of practice of nurses undertaking courses in intensive care nursing within one higher education Institution is presented and examined. The potential implications of these developments for practice and education are outlined.
Organ and tissue donation: a trustwide perspective or critical care concern?
Authors: Elding Christine , Scholes Julie 
Published: April 2005

AbstractOrgan donation has become an accepted practice within the critical care setting; however, tissue donation is seldom considered within the ICU environment and even less in other hospital departments.This study describes the results from an early base line audit performed as the first stage in a larger action research project following the implementation of the Donor Liaison Scheme in an NHS trust. It was designed to assess the current level of knowledge, confidence and value system staff have, working in all areas of the hospital setting in relation to organ and tissue donation.The results from this audit highlight key areas for practice development across all areas of this NHS trust.Many healthcare professionals working within this trust are unaware that donation can be considered. The respondents identified a lack of knowledge and confidence to be able to identify and discuss the options of donation with a family, yet the majority believe strongly that a person's wishes should be respected after death.People who have signed on the NHS ODR anticipate that healthcare professionals will access the ODR and support their family in following through their wishes; therefore, all healthcare professionals should receive education on donation issues as an integral part of bereavement and end of life decision training.Education strategies that adopt an experiential approach should be developed in order to create confidence in healthcare professionals to offer choice in donation options