bluuebunny/crossref_metadata_2025 huggingface dataset:
The seafloor swells and Superswell in French Polynesia
Authors: Sichoix L. , Bonneville A. , McNutt M. K.
Published: February 2004

High‐quality ship soundings obtained since 1967 in French Polynesia are used to better define the pattern of depth anomalies in French Polynesia and to test the accuracy of previous results based on ETOPO5 gridded data. The modes of the differences between the ship data and ETOPO5 demonstrate that the latter database is accurate to ±250 m for nearly 70% of the observations in the region, although there is a tendency for ETOPO5 to be of the order of 35 m too shallow. The ship depth versus age distribution shows that the South Pacific's unusually shallow seafloor, termed the “Superswell,” cannot simply be described as the cooling of a hotter or thinner thermal plate. Rather, the seafloor rises between the ages of ∼40 and 80 million years before resuming thermal subsidence. The Superswell appears to be bounded to the north by the Marquesas Fracture Zone, and the depth anomaly tapers down to smaller values south of the Austral Fracture Zone. Its modal‐depth‐versus‐age relation cannot be mimicked easily by classical steady state thermal cooling models, leading us to prefer dynamic explanations for the depth anomaly. Modal depth analysis aids in the isolation of the individual swells superimposed on the Superswell. Whereas the Marquesas swell, just north of the Superswell, is similar to other swells worldwide in its width (>1000 km) and amplitude (∼1 km), both the Society and Austral swells are narrower and lower than global norms. We explain the small size of the Society and Austral swells as the reduced thermal buoyancy of these hotspots entrained in a broader mantle upwelling.
A model for the origin of Himalayan anatexis and inverted metamorphism
Authors: Harrison T. Mark , Grove Marty , Lovera Oscar M. , Catlos E. J.
Published: February 2004

The origin of the paired granite belts and inverted metamorphic sequences of the Himalaya has generally been ascribed to development of the Main Central Thrust (MCT). Although a variety of models have been proposed that link early Miocene anatexis with inverted metamorphism, recent dating studies indicate that recrystallization of elements of the MCT footwall occurred in the central Himalaya as recently as ∼6 Ma. The recognition that hanging wall magmatism and footwall metamorphism are not spatially and temporally related renders unnecessary the need for exceptional physical conditions to explain generation of the High Himalayan leucogranites and North Himalayan granites, which differ in age, petrogenesis, and emplacement style. We suggest that their origin is linked to shear heating on a continuously active thrust that cuts through Indian supracrustal rocks that had previously experienced low degrees of partial melting. Numerical simulations assuming a shear stress of 30 MPa indicate that continuous slip on the Himalayan decollement beginning at 25 Ma could trigger partial melting reactions leading to formation of the High Himalayan granite chain between 25 and 20 Ma and the North Himalayan belt between 17 and 8 Ma. The ramp‐flat geometry we apply to model the Himalayan thrust system requires that the presently exposed rocks of the hanging wall resided at middle crustal levels above the decollement throughout the early and middle Miocene. Late Miocene, out‐of‐sequence thrusting within the broad shear zone beneath the MCT provides a mechanism to bring these rocks to the surface in their present location (i.e., well to the north of the present tectonic front) and has the additional benefit of explaining how the inverted metamorphic sequences formed beneath the MCT. We envision that formation of the MCT Zone involved successive accretion of tectonic slivers of the Lesser Himalayan Formations to the hanging wall and incorporate these effects into the model. The model predicts continued anatexis up to 400 km north of the Himalayan range, consistent with the timing and geochemistry of leucogranites exhumed on the flank of a south Tibetan rift.
Wavelet analysis of the Chandler wobble
Authors: Gibert Dominique , Holschneider Matthias , Le Mouël Jean‐Louis
Published: February 2004

Wavelet analysis is applied to analyze polar motion spanning the years 1890–1997. First, the wavelet transform is used to identify the components (prograde and retrograde) present in the data. This wavelet transform is subsequently used to filter and reconstruct each component. Then we define the ridge of the wavelet transform and show how it can be used to detect rapid phase jumps in a signal. This technique is applied to the reconstructed prograde Chandler wobble component, and several features characteristic of phase jumps are identified. Synthetic signals with adjustable phase jumps (in terms of their dates, durations, and amplitudes) are constructed to produce ridge functions similar to the one obtained for the Chandler wobble. We find that less than 10 phase jumps are necessary to reproduce the observed features. All but one phase jump have durations between 1 and 2 years, and their dates are found to remarkably follow those of geomagnetic jerks with a delay not exceeding 3 years. Elementary statistical tests assign a high probability to the correlation between the dates of the phase jumps and those of the jerks. Simple physical models of core‐mantle coupling show that the observed phase jumps can be recovered with torques of about 1020Nm.
Low‐frequency shear attenuation in polycrystalline olivine: Grain boundary diffusion and the physical significance of the Andrade model for viscoelastic rheology
Authors: Gribb Tye T. , Cooper Reid F.
Published: February 2004

The high‐temperature (1200–1285°C) torsional dynamic attenuation (10−3–100 Hz) and unidirectional creep behavior of a fine, uniform grain sized (d ≈ 3 μm) olivine (∼Fo92) aggregate have been measured. In all cases, the material is found to be mechanically linear (i.e., γ(t), γ ∝ σxy1), indicating that diffusional processes dominate the deformation kinetics in these experiments. The creep response displays a large decelerating transient in the strain rate leading to a nominally constant “steady state.” The attenuation behavior displays a band in QG−1 that is moderately dependent on frequency (QG−1 ≈ f−0.35) and temperature with −1.5<log(QG−1)<0.5. The creep and attenuation behaviors are accurately represented by a compliance function based on the Andrade model of viscoelasticity, which incorporates a power law description of anelastic strain (i.e., γα ∝ tn with n ≈ ½), and its Laplace transform, respectively. The uniformity of the material and the nature of its dynamic response allow the argument that the power law transient has a physical interpretation: because the attenuation band is not associated with a range of grain sizes or a distribution of lattice dislocations, the transient term describes the intrinsic transient in diffusional creep, which arises due to the evolution of tractions on the grain boundaries and is effected by chemical diffusion within a diminishing potential. Employing the rheological model of Raj [1975] for the intrinsic transient, we demonstrate that the “high‐temperature background” absorption can be predicted from the creep response; a master curve description of the attenuation results. Comparison of these data to those of previous investigators, and contemplating their application to the upper mantle, raises the suggestion, explored in this paper, that the subgrain size may prove the critical microstructural variable effecting the broad attenuation band seen in all experiments as well as in the upper mantle.
The thermal history of the New York basement determined from 40Ar/39Ar K‐feldspar studies
Authors: Heizler Matthew T. , Harrison T. Mark
Published: February 2004

Constraints on the thermochronologic evolution of the New York crystalline basement are mainly restricted to the high‐temperature early cooling history following 1.1 Ga Grenville metamorphism (U‐Pb methods) and the late cooling history (fission track methods). The thermal history for the ∼one billion years between these intervals is herein assessed using 40Ar/39Ar hornblende, muscovite, biotite and K‐feldspar thermochronology. Hornblende preferred ages suggest cooling below ∼450–500°C between ca. 900 and 950 Ma. Total gas ages of biotites range from ∼746–1060 Ma, and their age spectra complexity is probably related to younger thermal events and/or excess argon. A single muscovite analysis yields a preferred age of 854 Ma. Argon isotope analyses of K‐feldspar provide a quantitative evaluation of the thermal history between ∼175 and 350°C. Multi‐diffusion domain thermochronology on highly variable K‐feldspar results yield internally consistent thermal histories and, along with geologic constraints, suggest thermal maxima of 275–350°C at ca. 700, 470–450 and 300 Ma. Combining all of the K‐feldspar analyses provides an internally consistent thermal history for the region and allows for the following inferences. Reheating at ∼700 Ma associated with Late Precambrian rifting during the formation of the Iapetus ocean apparently affected the entire Adirondack region with the highest temperatures occurring in the eastern part of New York. Local reheating in the Ordovician is inferred to have affected the eastern Adirondack Mountains and probably resulted from the combined effects of burial during the Early Paleozoic, emplacement of Taconic thrust sheets and migration of hot fluids along normal faults during the Taconic orogeny. High paleotemperatures for the Devonian section of eastern New York are related to maximum burial of the basement during the Carboniferous at ca. 300 Ma.
Does reducing malaria improve household living standards?
Authors: Laxminarayan Ramanan
Published: February 2004

Living in malaria‐endemic regions places an economic burden on households even if they do not actually suffer an episode of malaria. Households living in endemic malarial regions are less likely to have access to economic opportunities and may have to modify agricultural practices and other household behaviour to adapt to their disease environment. Data from Vietnam demonstrate that reductions in malaria incidence through government‐financed malaria control programmes can contribute to higher household income for all households in endemic areas. Empirically, the roughly 60% decline in malaria cases over the 1990s in Vietnam translated to a $12.60 average improvement in annual consumption of all households, or a roughly $180 million annual economic benefit in the form of improved living standards.
Efficacy of chloroquine, amodiaquine, sulphadoxine–pyrimethamine and combination therapy with artesunate in Mozambican children with non‐complicated malaria
Authors: Abacassamo F. , Enosse S. , Aponte J. J. , Gómez‐Olivé F. X. , Quintó L. , Mabunda S. , Barreto A. , Magnussen P. , Rønn A. M. , Thompson R. , Alonso P. L.
Published: February 2004

This paper reports a two‐phase study in Manhiça district, Mozambique: first we assessed the clinical efficacy and parasitological response of Plasmodium falciparum to chloroquine (CQ), sulphadoxine–pyrimethamine (SP) and amodiaquine (AQ), then we tested the safety and efficacy in the treatment of uncomplicated malaria, of three combinations: AQ + SP, artesunate (AR) + SP and AQ + AR. Based on the WHO (1996, WHO/MAL/96.1077) in vivo protocol, we conducted two open, randomized, clinical trials. Children aged 6–59 months with axillary body temperature ≥37.5 °C and non‐complicated malaria were randomly allocated to treatment groups and followed up for 21 days (first and second trial) and 28 days (first trial). The therapeutic efficacy of AQ (91.6%) was better than that of SP (82.7%) and CQ (47.1%). After 14 days, 69% of the strains were parasitologically resistant to CQ, 21.4% to SP and 26% to AQ. Co‐administration of AQ + SP, AR + SP and AQ + AR was safe and had 100% clinical efficacy at 14‐day follow‐up. The combination therapies affected rapid fever clearance time and reduced the incidence of gametocytaemia during follow‐up.
Efficacy of sulphadoxine–pyrimethamine alone or combined with amodiaquine or chloroquine for the treatment of uncomplicated falciparum malaria in Ugandan children
Authors: Talisuna Ambrose O. , Nalunkuma‐Kazibwe Anne , Bakyaita Nathan , Langi Peter , Mutabingwa Theonest K. , Watkins William W. , Van Marck Eric , D'Alessandro Umberto , Egwang Thomas G.
Published: February 2004

The rapid development of falciparum resistance to sulphadoxine–pyrimethamine (SP) in East and Central Africa has raised concerns as to the efficacy of combining it with another drug. In 2002, we assessed the efficacy of SP alone and combined with amodiaquine (AQ/SP) or chloroquine (CQ/SP) in Ugandan children with uncomplicated falciparum malaria. At day 14, adequate clinical response was 100% (84/84) for AQ/SP, 93% (92/101) for CQ/SP and 91% (73/80) for SP. At day 28, parasitological failure (RI–RIII) occurred in 16% (13/80) of children treated with AQ/SP, in 48% (48/100) of those treated with CQ/SP and in 61% (48/79) of those treated with SP alone. Compared with the AQ/SP arm, the odds for parasitological failure at day 28 were five times higher (95% CI, 2–10) in the CQ/SP group and sevenfold higher (95% CI, 3–17) in that of SP alone. CQ/SP does not offer any significant added benefit over SP alone while AQ/SP is an efficacious low‐cost combination. These findings have important policy implications for Uganda and other resource‐constrained African countries faced with the problematic choice of a new first‐line antimalarial treatment in a context of high CQ resistance.
Post‐injury malaria: a risk factor for wound infection and protracted recovery
Authors: Sundet Mads , Heger Tove , Husum Hans
Published: February 2004

Objective  To assess the impact of post‐injury falciparum malaria on morbidity parameters in Cambodia.

Method  Retrospective study of 227 trauma patients managed at a surgical centre in Battambang, Cambodia.

Results  Within 10 days of the injury, 42.7% of the study population developed symptomatic malaria. In patients with post‐injury malaria, the rate of wound infection was 36.1% compared with 10.0% in patients without symptomatic malaria (95% confidence interval for difference 15.2–36.9%). The average hospital stay in the post‐injury malaria group was 31.2 days compared with 19.4 days in the patients without the complication (95% confidence interval for difference 7.2–16.4 days).

Conclusion  Symptomatic malaria after trauma is common in Cambodia. Post‐injury malaria seems to increase the risk of wound infection, delays postoperative recovery, and thus adds to the burden of trauma.
Out‐of‐pocket health expenditure and debt in poor households: evidence from Cambodia
Authors: Damme Wim Van , Leemput Luc Van , Por Ir , Hardeman Wim , Meessen Bruno
Published: February 2004

Objectives  To document how out‐of‐pocket health expenditure can lead to debt in a poor rural area in Cambodia.

Methods  After a dengue epidemic, 72 households with a dengue patient were interviewed to document health‐seeking behaviour, out‐of‐pocket expenditure, and how they financed such expenditure. One year later, a follow‐up visit investigated how the 26 households with an initial debt had coped with it.

Results  The amount of out‐of‐pocket health expenditure depended mostly on where households sought care. Those who had used exclusively private providers paid on average US$103; those who combined private and public providers paid US$32, and those who used only the public hospital US$8. The households used a combination of savings, selling consumables, selling assets and borrowing money to finance this expenditure. One year later, most families with initial debts had been unable to settle these debts, and continued to pay high interest rates (range between 2.5 and 15% per month). Several households had to sell their land.

Conclusions  In Cambodia, even relatively modest out‐of‐pocket health expenditure frequently causes indebtedness and can lead to poverty. A credible and accessible public health system is needed to prevent catastrophic health expenditure, and to allow for other strategies, such as safety nets for the poor, to be fully effective.
IgE‐binding components of cultured human keratinocytes in atopic eczema/dermatitis syndrome and their crossreactivity with Malassezia furfur
Authors: Kortekangas‐Savolainen O. , Peltonen S. , Pummi K. , Kalimo K. , Savolainen J.
Published: February 2004

Background:  Atopic eczema/dermatitis syndrome (AEDS) patients display immunoglobulin E (IgE) reactivity to several antigens, e.g. saprophytic yeasts as Malassezia furfur. AEDS patients also show IgE autoreactivity towards cells of their own tissue including epidermis.

Purpose of the study:  The aim of this study was to investigate the IgE autoreactivity of AEDS patients to cultured keratinocytes and to reveal potential crossreacting epitopes in cultured keratinocytes and M. furfur.

Material and methods:  Serum samples of 27 AEDS patients were analyzed, of these 13 were M. furfur radioallergosorbent test (RAST) positive and 14 negative. Four urticaria, three psoriasis, and seven nonatopic patients were included as controls. The studies were performed by using IgE immunoblotting and immunoblotting inhibition methods.

Results:  Ten IgE‐binding protein bands were detected in cultured human keratinocytes by IgE immunoblotting using sera from adult AEDS patients. Anti‐keratinocyte IgE antibodies were more associated with elevated S‐IgE level than M. furfur RAST. Clear crossreactivity with M. furfur could not be shown.

Conclusions:  The possible pathomechanism of anti‐keratinocyte IgE antibodies is not due to IgE epitope mimicry of saprophytic yeast and local tissue in AEDS skin.
Molecular analysis of sequence variants in the Fcɛ receptor I β gene and IL‐4 gene promoter in Italian atopic families
Authors: Rigoli L. , Di Bella C. , Procopio V. , Barberio G. , Barberi I. , Caminiti L. , La Grutta S. , Briuglia S. , Salpietro C. D. , Pajno G. B.
Published: February 2004

Background:  The genetic variants in the Fcɛ receptor I β gene (Glu237Gly) and the T allele of the (C590T) polymorphism of interleukin (IL)‐4 gene promoter were reported to be associated with atopy. But the data of the studies in different populations are contrasting with one another.

Methods:  A group of 25 Italian nuclear families were studied. In each family at least two allergic subjects were present. The allergic children were 65 and the allergic relatives were 35. One hundred and three nonallergic unrelated controls included outpatiens with no history of atopy. The (C590T) promoter polymorphism of the IL‐4 and the genetic variant Glu237Gly of Fcɛ RI β genes were analysed by the polymerase chain reaction‐restriction fragment length polymorphism method.

Results:  A significant difference was observed in the genotype frequency at codon 237 of the Fcɛ RI β gene between allergic children and nonatopic control (P < 0.01) and in the allergic relatives (P < 0.001). In the children, the Glu237Gly polymorphism was also associated with elevated circulating levels of immunoglobulin E. The ‐590C/T allele of IL‐4 promoter gene showed no association with atopy.

Conclusions:  In our study, the Glu237Gly polymorphism of the Fcɛ RI β gene was associated with atopy. Our results have not pointed out an association between the (C590T) promoter polymorphism of the IL‐4 gene and atopy. These data suggest the potential role of the Fc RI β gene in the development of the allergy.
DYE LASER STIMULATION WITH A PULSED N2 LASER LINE AT 3371 Å
Authors: Myer James A. , Johnson C. L. , Kierstead E. , Sharma R. D. , Itzkan Irving
Published: February 2004

Dye laser action has been achieved with a pulsed N2 laser as the pumping source. The dye laser pulses vary in length from 2 to 10 nsec for the various dyes used and have been tuned to cover the entire visible spectrum with the proper choice of dyes and cavity optics. The system is capable, for some dyes, of repetition rates as high as 100 pulses/sec with reasonably good efficiencies.
SWITCHING AND NEGATIVE RESISTANCE IN THIN FILMS OF NICKEL OXIDE
Authors: Bruyere J. C. , Chakraverty B. K.
Published: February 2004

A pronounced negative resistance and ultrarapid switching between an initial insulating state and a conducting state has been observed in thin films of NiO at room temperature. The switching is reversible with respect to polarity change and quite stable even after repeated cycling.
OBSERVATION OF MICROWAVE REPOPULATION MODULATION IN n-Si AT 77 °K
Authors: Holm-Kennedy James W. , Champlin K. S.
Published: February 2004

The microwave (9.61 GHz, dielectric constant of n-Si was measured as a function of crystallographic orientation and as a function of applied dc electric field (warm electron conditions) at 77 °K lattice temperature. The dielectric constant was found to be anisotropic. An analysis of the results correlated with the observed free carrier repopulation shows a new contribution to the microwave properties. This contribution arises from a repopulation modulation at the microwave frequency.
EXPERIMENTS WITH A CO2 GAS-DYNAMIC LASER
Authors: Kuehn Donald M. , Monson Daryl J.
Published: February 2004

Experiments with a CO2 gas-dynamic laser were run in a shock-tube facility. Population inversion of the CO2 molecule was achieved by expansion of heated test gas through a supersonic nozzle. Measurements included shape, time, and energy of the laser output, and beam diameter. Beam divergence and mirror deterioration were reduced by changes in optical cavity geometry. Laser power was optimized for temperature, fraction of He in the test gas, and output-mirror transmissivity. Maximum laser power was 250 W for a 100-cm3 cavity with a 20-cm gain path.
MAGNETOPLASMA RESONANCE IN SEMICONDUCTOR POWDERS
Authors: Chen K. K. , Galeener F. L. , Furdyna J. K.
Published: February 2004

We report a new class of resonant interactions of circularly polarized microwaves with powdered n-type InSb, which is observed only in the cyclotron resonance inactive polarization, at magnetic fields independent of particle size. The new powder resonance is a multiparticle analog of the single-particle magnetoplasma resonance first reported by Dresselhaus, Kip, and Kittel. Both the position and strength of the observed powder resonance are discussed quantitatively using the Rayleigh extinction cross section for a single particle.
DOUBLE INJECTION IN LONG p-i-n DIODES WITH DEEP DOUBLE-ACCEPTOR IMPURITIES
Authors: Weber Willes H.
Published: February 2004

Double injection in long p-i-n diodes heavily doped with deep double-acceptor impurities is discussed. Expressions for the current-voltage relations in various regimes are derived, and an expression is given for the breakdown voltage characterizing the onset of the negative resistance. As an example, results for Zn-doped Si are given using estimates of the capture coefficients.
NEAR uv TO YELLOW TUNABLE LASER EMISSION FROM AN ORGANIC DYE
Authors: Shank C. V. , Dienes A. , Trozzolo A. M. , Myer J. A.
Published: February 2004

Tunable laser emission from 3850 to 5740 Å has been observed from three solvate forms of 4-Methylumbelliferone. The three distinct lasing forms basic, neutral, and acid, with tuning ranges of 1070, 720, and 1150 Å, respectively, were obtained by adjusting the solvent pH. A tuning range of 1760 Å (from 3910 to 5670 Å) has been obtained in a critically adjusted, slightly acidic solution. The various chemical structures responsible for the broad tuning have been identified. Evidence that the acid form lases from an exciplex (excited complex) state is presented.
TRACER EXPERIMENTS ON THE GROWTH OF TIN WHISKERS
Authors: Kehrer H.-P. , Kadereit H. G.
Published: February 2004

Tracer experiments on the growth of proper whiskers from evaporated tin layers indicate the existence of solid or nearly solid as well as hollow whiskers. The presence of oxygen during evaporation, resulting in a rapid whisker growth, inhibits large scale diffusion. This inhibition effect must be released, however, at small regions, corresponding to the roots of the whiskers.
A 964-GHz TRAVELING-WAVE ELECTRO-OPTIC LIGHT MODULATOR
Authors: Kaminow I. P. , Bridges T. J. , Pollack M. A.
Published: February 2004

A 0.633-μ m laser has been modulated at 964 GHz (311 μ m) and 891 GHz (337 μ m) by a novel phase-matched LiNbO3 electro-optic modulator driven by an HCN laser. The performance of the modulator agrees with calculations based on the radio-frequency electro-optic coefficient. Similar experiments with a CdS modulator were unsuccessful presumably because of the generation of photocarriers.
ROOM-TEMPERATURE CO LASER
Authors: Mann M. M. , Bhaumik M. L. , Lacina W. B.
Published: February 2004

High-power cw operation of a carbon monoxide laser at room temperature (20 °C) has been achieved by introducing mercury vapor into the discharge. In the initial experiments, a cw output power of 1.4 W corresponding to an efficiency of 1.8 % was obtained with a nonoptimized cavity.
CONTINUOUS-WAVE NONSPIKING SINGLE-MODE RUBY LASERS
Authors: Birnbaum Milton , Wendzikowski Paul H. , Fincher Curtis L.
Published: February 2004

Continuous-wave nonspiking single-mode operation of ruby lasers cooled to 77 and 4.2 °K was obtained by end pumping the ruby with the 5145 Å output of a cw argon ion laser. Measurements of the output of the cw ruby laser showed single mode (TEM00q) operation with a full spectral width of approximately 35 kHz.
EPITAXIAL ZnO ON SAPPHIRE
Authors: Galli G. , Coker J. E.
Published: February 2004

Epitaxial layers of ZnO have been deposited by chemical vapor transport on single-crystal sapphire substrates. The ZnO layers have been deposited up to thicknesses of 100μ. X-ray analysis showed that the c axis of the ZnO could be made to lie parallel to the (0112)-oriented sapphire substrate. Resistivities were generally from 1 to 10 Ω-cm but could be significantly increased by diffusion of lithium or sodium.
INSTANTANEOUS VIDEO DISPLAY OF X-RAY TOPOGRAPHIC IMAGES WITH RESOLVING CAPABILITIES BETTER THAN 15μ
Authors: Rozgonyi G. A. , Haszko S. E. , Statile J. L.
Published: February 2004

A silicon diode array target has been used as an image transducer for x rays in a closed-circuit television system. It is shown that x-ray topographs of images smaller than 15μ can be displayed essentially instantaneously on a television monitor. In addition, the magnification of the topograph can be controlled electronically and individual video scan lines can be presented on an oscilloscope to give an intensity plot across the x-ray topograph.
OPTICALLY PUMPED Cd3P2 LASER
Authors: Bishop S.G. , Moore W.J. , Swiggard E.M.
Published: February 2004

Coherent laser oscillation with wavelength near 2.12μ has been achieved in as-grown crystal of Cd3P2 at 4.2°K using pulsed optical excitation from a Q-switched Nd-doped YAG laser.
PHOTOELECTRONIC PROPERTIES OF ION-IMPLANTED CdS
Authors: Hou S. L. , Marley J. A.
Published: February 2004

The photoelectronic properties of CdS successively implanted with 1.0-, 0.5-, and 0.3-MeV P+ ions versus annealing cycles were studied. Diodes thus formed were highly photosensitive, with photoconductive gains between 102 and 104. Yellow electroluminescence was observed at 77°K. Short annealing creates centers with a sheet resistance thermal activation energy of 0.13 eV. Prolonged annealing creates states 0.75–0.8 eV below the band edge.
SIMPLE TEST FOR DOUBLE INJECTION INITIATION OF SWITCHING
Authors: Balberg I.
Published: February 2004

A simple pulse measurement is suggested to check whether the switching phenomena in materials and devices is due to double injection. In the Ovshinsky Threshold Switch used in the present measurement, it is found that this model cannot account for the observation. The results seem to support the ``thermal models'' for the initiation of the switching in this device.
TRANSVERSELY EXCITED ATMOSPHERIC PRESSURE CO2 LASERS
Authors: Beaulieu A. J.
Published: February 2004

Laser action at 10. 6 μm has been achieved in CO2–N2–He gas mixtures at all pressures up to atmospheric by means of fast electrical discharges transverse to the laser axis. The atmospheric pressure of operation is very promising as the laser energy per pulse increases with pressure and the average power per unit volume is proportional to the square of the operating pressure. A brief description of a simple laser of this type, operating at atmospheric pressure is given along with some of the major achievements to date using this technique.
GRATING COUPLER FOR EFFICIENT EXCITATION OF OPTICAL GUIDED WAVES IN THIN FILMS
Authors: Dakss M. L. , Kuhn L. , Heidrich P. F. , Scott B. A.
Published: February 2004

We report a new method of coupling a laser beam to thin-film optical guided waves which utilizes an optical grating that is made from photoresist and fabricated directly on the film. High efficiency coupling (∼40 %) into a single mode in a glass film is observed.
MEASUREMENT OF ION IMPLANTATION LATTICE DAMAGE IN (111) GaAs USING THE SCANNING ELECTRON MICROSCOPE
Authors: Wolf E. D. , Hunsperger R. G.
Published: February 2004

We have measured the Coates-Kikuchi pattern degradation of (111) GaAs in the 5- to 30-keV incident electron energy range as a function of 60-keV cadmium ion dose (1012 to 1015 Cd+/cm2) at room temperature. Pattern degradation is greater for a given dose at 5-keV than it is at 30-keV incident electron energy. Agreement is found between the pattern degradation and measurements of lattice disorder as determined by backscattering of 1-MeV helium ions. Annealing of the ion-bombarded samples at temperatures up to 450°C restores the Coates-Kikuchi pattern quality as the lattice damage is reduced.
EQUILIBRIUM GAS SCATTERING FROM CLEAVED LiF
Authors: Palmer R. L. , O'Keefe D. R.
Published: February 2004

The equilibrium scattering behaviors of He, H2, and Ar from the cleavage plane of LiF have been measured in order to provide a critical test of the cosine law of total scattering for cases where this result is not the redundant result of Knudsen law (diffuse) scattering. These results confirm the general validity of the cosine law and suggest certain symmetry properties of gas-surface scattering which apparently have not heretofore been recognized.
EFFICIENT PURELY CHEMICAL cw LASER OPERATION
Authors: Cool Terrill A. , Stephens Ronald R.
Published: February 2004

Continuous-wave laser operation at 10.6μ has been achieved in the DF–CO2 and HF–CO2 molecular systems by purely chemical means. No external energy sources are required; both lasers operate solely by the simple mixing of bottled gases. Experimental results are presented which demonstrate that cw chemical laser operation at high power and high efficiency is realizable in the DF–CO2 system.
DYNAMIC SCATTERING IN A ROOM-TEMPERATURE NEMATIC LIQUID CRYSTAL
Authors: Jones Derick , Creagh Linda , Lu Sun
Published: February 2004

The dynamic scattering characteristic of a room-temperature nematic liquid crystal is described. This electro-optic effect has been observed in many high-temperature nematic liquid crystals. The material described here has a mesomorphic phase from 11 to 41 °C. A contrast ratio of 30 to 1 is observed with a field of 3.7×104V/cm.
SELECTIVE PERTURBATION OF A MERCURY INFRARED TRANSITION BY A FAST Nd-LASER PULSE
Authors: Platz Peter
Published: February 2004

Fast pulses from a Nd: glass laser (10 600 Å), with a rise time of 0.7 nsec and a length of 1.3 nsec at half-intensity interact with mercury atoms via the 73S1 − 73P2 transition (11 287 Å). The 73S1 level shifts instantaneously to higher energies by 0.29 × 10−6 eV for a laser power of 1 MW/cm2. Theoretical behavior of the 73S1 level is given. The absorption oscillator strength of the 73S1 − 73P2 transition is deduced to be 0.32±0.06.
HIGHER ELECTRIC FIELDS FOR STARK-INDUCED INFRARED SPECTRA
Authors: Boyd W. J. , Brannon P. J. , Gailar N. M.
Published: February 2004

A Stark cell to study the normally inactive infrared spectrum of homonuclear diatomic molecules has been built. This cell utilizes parallel metal plates to apply high electric fields across the sample gas. Fields of 240 000 V/cm in H2 and 350 000 V/cm in N2 have been achieved at 400 psi using the new cell. The electric-field-induced pure rotation infrared spectra of H2 was observed. The frequencies of the S0(2), and S0(3) pure rotation lines were measured, and the molecular constants B0, D0, and H2 were calculated from these data.
TECHNIQUE OF MAPPING ACOUSTIC FIELDS BY MEANS OF A POLAROID FILM
Authors: Iizuka Keigo
Published: February 2004

A standard Polaroid film was proved to be applicable to a quick and easy direct mapping of an acoustic field. The method utilizes the effect of an acoustic field on the developing process of a uniformly pre-exposed Polaroid film. The method would be most useful for visualization of acoustic field as well as preparing acoustic holograms.
DIRECT OBSERVATION OF A DYNAMIC BURSTEIN SHIFT IN A GaAs:Ge PLATELET LASER
Authors: Dapkus P. D. , Holonyak N. , Burnham R. D. , Keune D. L.
Published: February 2004

Data (77°K) are presented showing a dynamic Burstein shift of the absorption edge during spontaneous and laser operation of GaAs:Ge platelets. This is indicated directly by an increase in the relative transmission of the pump power through the sample with increased pump excitation. By the use of pumps with photon energies (1.527 eV) closely matched to the GaAs absorption edge (1. 513 eV), changes in the relative transmission of from 4 to 30% have been achieved. The data presented also show a change in the rate of decrease of the absorption with the onset of stimulated emission by the platelet.
ON THE PROPAGATION OF HIGH-CURRENT BEAMS OF RELATIVISTIC ELECTRONS IN GASES
Authors: Andrews M. L. , Davitian H. , Hammer D. A. , Fleischmann H. H. , Nation J. A. , Rostoker N.
Published: February 2004

The transit time of high current beams of relativistic electrons (40–50 kA, 350 keV) through an air filled (0.2–2.5 Torr) drift tube has been measured. It is longer than expected, even allowing for the loss of beam front electrons and for orbiting of the electrons in the beam self-magnetic field. Also, a pressure-dependent nonuniformity in the beam motion was observed which may account for this delay.
ELECTRIC FIELD HYSTERESIS EFFECTS IN CHOLESTERIC LIQUID CRYSTALS
Authors: Melamed L. , Rubin D.
Published: February 2004

Certain room-temperature cholesteric liquid crystals are capable of retaining information on their past history of electric field excitation by exhibiting marked changes in their optical transmission properties. The information retention slowly decays but in many cases persists for at least several days following the removal of excitation. Thus 100 V applied across a 25 μ sample for 10 min caused a change in transmission at 5000 Å from 75 to about 22%. Sixty hours later, the transmission was about 48%.
ORIENTATIONAL OSCILLATIONS IN NEMATIC LIQUID CRYSTALS
Authors: Heilmeier G. H. , Helfrich W.
Published: February 2004

It is shown that ac electric fields can produce orientational oscillations in nematic liquid crystals. The oscillations are observed in thin sandwich cells and probably due to parametric excitation. They are associated with a strong electro-optic effect, similar to dynamic scattering, but with faster turn-off times (< 5 msec).
OPTICAL DAMAGE IN KDP
Authors: Wax S. I. , Chodorow M. , Puthoff H. E.
Published: February 2004

We report a reversible optical damage effect when KDP is illuminated in the presence of an applied electric fieid. The damage is slight and has a relaxation time of seconds, but it produces a substantial reflection when the illumination takes the form of a standing wave. An experiment to observe this phenomenon, using a ring laser, is described. The damage is attributed to trapping of photoexcited electrons.
IONIZATION SPECTROSCOPY OF SURFACES
Authors: Gerlach Robert L. , Houston J. E. , Park Robert L.
Published: February 2004

A technique is described for the analysis of surface composition on the basis of characteristic loss features associated with electron impact ionization of inner atomic levels. The method involves separating the characteristic loss spectrum from the total secondary emission spectrum by superimposing a small oscillation on the primary beam energy and detecting only those features which fluctuate at the same frequency. Ionization spectroscopy is shown to have a number of inherent advantages over conventional Auger spectroscopy.
DIRECT GAIN MEASUREMENTS OF AN ORGANIC DYE AMPLIFIER
Authors: Huth B. G.
Published: February 2004

Amplifier gain measurements were made on the dye rhodamine 6G in ethanol. Gain was measured as a function of wavelength and time for a 1 × 10−4 M solution. The peak gain coefficient was measured to be 95 dB/m at a pump energy of 21.5 J. This same pump energy produced 55 mJ of laser output from a 3.8-cm-long cell in a mode diameter of 3.6 mm.
DIFFUSION OF ELECTRONS IN SILICON TRANSVERSE TO A HIGH ELECTRIC FIELD
Authors: Bartelink D. J. , Persky G.
Published: February 2004

A new method for directly measuring diffusion coefficients transverse to a high electric field has been applied to electrons in silicon at 300°K. For fields ranging up to 24 kV/cm, the transverse diffusion coefficient, as measured and determined by Monte Carlo calculation, indicates a drop from the zero field value D0 to approximately D0/2. The present results are subject to some uncertainty, but improved resolution appears to be attainable with maximum use of present technology.
THE ``EPICON'' ARRAY: A NEW SEMICONDUCTOR ARRAY-TYPE CAMERA TUBE STRUCTURE
Authors: Engeler W. E. , Blumenfeld M. , Taft E. A.
Published: February 2004

A new target structure for a television camera tube consisting of an array of capacitors and p-n junctions, formed by a deposited epitaxial layer, is described. The epitaxial growth forms a series of pyramidal shaped structures on top of the patterned oxidized wafer. These silicon structures form an array of capacitors with the substrate and cover much of the oxide layer. They are separated by micron-size gaps and project several microns above the oxide surface. Contact to the substrate is made through an array of apertures where p-n junctions are formed. By intercepting the electron beam, these structures obviate the need for a resistive sea and are expected to minimize material compatibility and thermal processing problems.
THERMAL LASER EXCITATION BY MIXING IN A HIGHLY CONVECTIVE FLOW
Authors: Bronfin Barry R. , Boedeker Laurence R. , Cheyer John P.
Published: February 2004

Population inversion has been generated through the mixing of CO2 or N2O into a supersonic N2 flow, vibrationally excited by thermal means. Gain at 10.6μ, corresponding to the 001 → 100 transition in CO2, equal to 0.8%/cm has been measured in this medium. Using an optical cavity, oriented transverse to the flow, up to 60-W cw laser power at 10.6μ from CO2 was extracted from a 5-cm length by 1.2-cm2 cross-section active volume. When N2O was substituted for CO2 in the mixing region, cw laser emission was demonstrated at 10.8μ, corresponding to the 001 → 100 transition in N2O.
SINGLE-FREQUENCY OSCILLATION USING TWO COUPLED CAVITIES INCORPORATING A FABRY-PEROT ELECTRO-OPTIC MODULATOR
Authors: Kobayashi T. , Matsuo Y.
Published: February 2004

A single-frequency laser oscillation was obtained by using two coupled cavities incorporating a Fabry-Perot electro-optic modulator. Although the modulation frequency was as low as 1.0 MHz, the variation of the output power was negligibly small. The output power obtained in the single-frequency oscillation was about 80% of the total power in multifrequency oscillation. This method requires fewer mirrors than that of Smith; therefore, it is expected that the output frequency and power may be easily stabilized.
MAGNETOELASTIC LOVE WAVES IN A MAGNETIC LAYERED NONMAGNETIC SUBSTRATE
Authors: van de Vaart H. , Matthews H.
Published: February 2004

The dispersion relation for magnetoelastic Love waves propagating in a magnetic thin film supported by a nonmagnetic substrate is derived. It is shown that the interaction between elastic Love waves and magnetostatic surface waves is nonreciprocal and depends on the mode number of the Love wave.
HOLOGRAPHY OF RANDOMLY MOVING OBJECTS
Authors: Caulfield H. J.
Published: February 2004

Mottier's technique of matching the reference beam modulation to the object beam modulation is shown to be a special case of local reference beam (LRB) holography. A hand-held object beam mirror is used to produce a good LRB hologram. A new form of LRB holographic interferometry, which measures the changes with respect to a preselected part of the object, is discussed.
PRELIMINARY PERFORMANCE OF A cw CHEMICAL LASER
Authors: Spencer D. J. , Mirels H. , Jacobs T. A. , Gross R. W. E.
Published: February 2004

Preliminary performance of a cw chemical laser is presented. Hydrogen is diffused into a supersonic stream containing F atoms. Population inversion is due to the reaction H2+F→ HF(v)+H, ΔH=−31.7 kcal/mole, v=1, 2. An atomic F flow rate of 0.030 moles/sec has produced 475 W of laser power in the 3-μ region. This represents 12% of the chemical energy involved in the above reaction. Zero power gain is 8%/cm. Spectroscopic observations of laser transitions are included.
CARBON MONOXIDE FORMATION IN CO2 LASERS
Authors: Wiegand W. J. , Fowler M. C. , Benda J. A.
Published: February 2004

The rate of CO2 dissociation in a flowing CO2 laser discharge has been measured. This rate is consistent with published cross sections for direct electron impact dissociation when averaged over the appropriate electron energy distribution. The dissociation process in the flowing gas discharge is found to result in an axial variation of plasma properties and of the laser medium. Implications of the CO variation for many conventionally operated CO2 lasers are discussed.
SPONTANEOUS PARAMETRIC SCATTERING OF LIGHT IN LiIO3
Authors: Campillo A. J. , Tang C. L.
Published: February 2004

cw spontaneous parametric scattering in LiIO3 has been observed. The results show that the nonlinear coefficient d31 for LiIO3 is ∼18×10−9 esu. The ordinary index of refraction curve for this crystal has also been determined from 1.2μ past the ir-absorption edge at 5.4μ to near 7μ; no resonance in the nonlinear susceptibility was found near this particular absorption band.
BEHAVIOR OF SOLENOIDS IN TYPE I SUPERCONDUCTING SHIELD TUBES
Authors: Schweitzer Donald G. , Garber M.
Published: February 2004

A model is described which accounts for the observed properties of solenoids in superconducting shield tubes.
ABSOLUTE FREQUENCY MEASUREMENTS OF THE CO2 cw LASER AT 28 THz (10.6μm)
Authors: Evenson K. M. , Wells J. S. , Matarrese L. M.
Published: February 2004

The two highest cw absolute frequency measurements as yet reported are described. Frequencies of the P(18) and P(20) 10.6-μm lines from a cwCO2 laser were found to be 28.359800 THz and 28.306251 THz±0.000025 THz, respectively. The frequencies were measured by beating each of these lines with 3.8-THz (78μm) and 10.7-THz (28μm) radiation from a water vapor laser and a 26- to 28-GHz klystron in a tungsten-on-nickel point contact diode.
LONG PULSE LASER EMISSION FROM RHODAMINE 6 G USING CYCLOOCTATETRAENE
Authors: Pappalardo R. , Samelson H. , Lempicki A.
Published: February 2004

Long pulse laser emission is obtained from Rhodamine 6 G using cyclooctatetraene to quench the triplet state of the dye. It is found that cyclooctatetraene is at least as effective as molecular oxygen.
SATURATION OF THE SELF-INDUCED THERMAL DISTORTION OF LASER RADIATION IN A WIND
Authors: Smith David C. , Gebhardt Frederick G.
Published: February 2004

When a laser beam propagates in an absorbing medium flowing transverse to the direction of propagation, the beam may be deflected and distorted by the self-induced thermal lens, which results from the absorbed laser beam energy. Experiments have been carried out examining the thermal bending and distortion of a cw CO2 laser beam in a 1-m-long wind tunnel. At the onset of the convection-controlled thermal distortion, the peak intensity of the laser beam is reduced and shifted into the wind. For experimental conditions leading to severe thermal distortion of the beam shape, it is observed that the deflection and decrease in the peak laser beam intensity tend to approach a constant value. This result is interpreted as a saturation of the convection-controlled, self-induced thermal lens which occurs when the thermal distortion is large and accompanied by a significant reduction in the minimum characteristic beam dimension. In the experiments reported, the path length and minimum characteristic beam dimensions associated with the thermal distortion were such that diffraction effects may be involved together with the thermal lens process in producing the observed saturation effect.
RADIATIVE RECOMBINATION FROM FIELD-EXCITED HOT CARRIERS IN n-GaAs
Authors: Southgate P. D. , Hall D. S.
Published: February 2004

Photoluminescent spectra have been measured in n-GaAs with applied fields of up to 2100 V cm−1. Hot electron distributions derived from the spectra are compared with drifted Maxwellian distributions having electron temperature equal to the lattice temperature.
ELASTIC WAVES GUIDED BY A FLUID LAYER: A NEW TYPE OF ULTRASONIC WAVE PROPAGATION
Authors: Wang W. C. , Staecker P. , Li R. C. M.
Published: February 2004

A new type of guided ultrasonic wave bound to a fluid layer between two elastic solids has been observed. Quantitative agreement has been obtained between experiment and theory.
OPTICAL NONLINEAR SUSCEPTIBILITIES OF LITHIUM IODATE
Authors: Jerphagnon J.
Published: February 2004

The nonlinear coefficients of lithium iodate have been measured, relative to quartz, by the Maker fringe technique. d31(LiIO3) = 15.5 ± 0.8 d11(SiO2),  d33(LiIO3) = 16.1 ± 1 [d11(SiO2)]for the fundamental wavelength 1.064μ. It has also been determined that d31 and d33 have the same sign.
THE LATTICE LOCATION OF BORON IONS IMPLANTED INTO SILICON
Authors: Fladda G. , Björkqvist K. , Eriksson L. , Sigurd D.
Published: February 2004

Channeling-effect measurements have been used to investigate the lattice location of boron atoms implanted into silicon at an energy of 56 keV and with doses in the interval 1014–1015 ions/cm2. Measurements have been made as a function of implantation temperature and subsequent anneal treatment. The effect of post-bombardment with different doses of 680-keV protons has also been investigated.
n-p JUNCTION PHOTODETECTORS IN InSb FABRICATED BY PROTON BOMBARDMENT
Authors: Foyt A. G. , Lindley W. T. , Donnelly J. P.
Published: February 2004

We have fabricated n-p junction photovoltaic detectors in InSb using proton bombardment to create the n-type layer. At 77 °K, diodes which were 20 mils in diameter had zero-bias resistances of several hundred thousand ohms. The peak detectivity at 4.9 μ of these diodes with a 2π, 300 °K background was typically greater than 3×1010 cm Hz1/2/W with the largest value observed being 1011 cm Hz1/2/W. Diode quantum efficiencies near 35% were observed.
RED-ORANGE PHOTOLUMINESCENCE IN TiO2: W
Authors: Lauer R. B. , Ghosh Amal K.
Published: February 2004

A red-orange photoluminescence emission band which peaks at approximately 2.02 eV was found in TiO2: W. The excitation and emission spectra for this band are presented. The previously reported 1.46-eV photoluminescence emission band which was attributed to interstitial Ti3+ ions is found to be quenched in the presence of tungsten. This result is interpreted in terms of the reduction of interstitial Ti3+ ions in the presence of tungsten. The 2.02-eV band is tentatively identified as an electron transition from states at or just below the conduction-band edge to an acceptorlike level approximately 1 eV above the edge of the valence band.
AN OPTOELECTRONIC COLD CATHODE USING AN AlxGa1−xAs HETEROJUNCTION STRUCTURE
Authors: Kressel H. , Kohn E. S. , Nelson H. , Tietjen J. J. , Weisberg L. R.
Published: February 2004

An efficient optoelectronic cold cathode has been made which includes a Si-compensated AlxGa1−xAs electroluminescent diode covered with an absorbing p-type GaAs layer having a negative electron affinity surface. This structure is designed to minimize current crowding in the vicinity of the Ohmic contact. An over-all efficiency of 1.1×10−3 (current emitted into vacuum/diode current) has been achieved. This represents a factor of 102–103 improvement over previous p-n junction or optically coupled cold cathode structures.