1,004 research outputs found
Fertilizer-Insecticide Mixtures on Corn
Soil fertility and insects are major factors that affect corn yields. The proper kinds and amounts of fertilizers and insecticides properly placed will make corn production more economical on fields where either or both are needed
Fertilizer-Insecticide Mixtures on Tobacco Plant Beds and Fields
Fertility and insect control programs have a major influence on tobacco production. The proper amounts and kinds of fertilizers and insecticides properly placed will make production more economical on beds and fields if either or both are needed.
Is a fertilizer-insecticide mix the best way to meet the fertility needs and t he insecticide needs on tobacco? The following questions and answers should help show how the decision was reached that this method is not recommended
Fertilizer-Insecticide Mixtures on Corn
Soil fertility and insects are major factors that affect corn yields. The proper kinds and amounts of fertilizers and insecticides when used properly will make corn production more economical on fields where either or both are needed
Oxidative stress participates in the breakdown of neuronal phenotype in experimental diabetic neuropathy
Ultrafast extreme ultraviolet photoemission without space charge
Time- and Angle-resolved photoelectron spectroscopy from surfaces can be used
to record the dynamics of electrons and holes in condensed matter on ultrafast
time scales. However, ultrafast photoemission experiments using
extreme-ultraviolet (XUV) light have previously been limited by either
space-charge effects, low photon flux, or limited tuning range. In this
article, we describe space-charge-free XUV photoelectron spectroscopy
experiments with up to 5 nA of average sample current using a tunable
cavity-enhanced high-harmonic source operating at 88 MHz repetition rate. The
source delivers photons/s in isolated harmonics to the sample over
a broad photon energy range from 18 to 37 eV with a spot size of m. From photoelectron spectroscopy data, we place conservative upper
limits on the XUV pulse duration and photon energy bandwidth of 93 fs and 65
meV, respectively. The high photocurrent, lack of space charge distortions of
the photoelectron spectra, and excellent isolation of individual harmonic
orders allow us to observe the laser-assisted photoelectric effect with
sideband amplitudes as low as , enabling time-resolved XUV
photoemission experiments in a qualitatively new regime
Observing the Sun with Atacama Large Millimeter/submillimeter Array (ALMA): High Resolution Interferometric Imaging
Observations of the Sun at millimeter and submillimeter wavelengths offer a
unique probe into the structure, dynamics, and heating of the chromosphere; the
structure of sunspots; the formation and eruption of prominences and filaments;
and energetic phenomena such as jets and flares. High-resolution observations
of the Sun at millimeter and submillimeter wavelengths are challenging due to
the intense, extended, low- contrast, and dynamic nature of emission from the
quiet Sun, and the extremely intense and variable nature of emissions
associated with energetic phenomena. The Atacama Large Millimeter/submillimeter
Array (ALMA) was designed with solar observations in mind. The requirements for
solar observations are significantly different from observations of sidereal
sources and special measures are necessary to successfully carry out this type
of observations. We describe the commissioning efforts that enable the use of
two frequency bands, the 3 mm band (Band 3) and the 1.25 mm band (Band 6), for
continuum interferometric-imaging observations of the Sun with ALMA. Examples
of high-resolution synthesized images obtained using the newly commissioned
modes during the solar commissioning campaign held in December 2015 are
presented. Although only 30 of the eventual 66 ALMA antennas were used for the
campaign, the solar images synthesized from the ALMA commissioning data reveal
new features of the solar atmosphere that demonstrate the potential power of
ALMA solar observations. The ongoing expansion of ALMA and solar-commissioning
efforts will continue to enable new and unique solar observing capabilities.Comment: 22 pages, 12 figures, accepted for publication in Solar Physic
Observing the Sun with the Atacama Large Millimeter-submillimeter Array (ALMA): Fast-Scan Single-Dish Mapping
The Atacama Large Millimeter-submillimeter Array (ALMA) radio telescope has
commenced science observations of the Sun starting in late 2016. Since the Sun
is much larger than the field of view of individual ALMA dishes, the ALMA
interferometer is unable to measure the background level of solar emission when
observing the solar disk. The absolute temperature scale is a critical
measurement for much of ALMA solar science, including the understanding of
energy transfer through the solar atmosphere, the properties of prominences,
and the study of shock heating in the chromosphere. In order to provide an
absolute temperature scale, ALMA solar observing will take advantage of the
remarkable fast-scanning capabilities of the ALMA 12m dishes to make
single-dish maps of the full Sun. This article reports on the results of an
extensive commissioning effort to optimize the mapping procedure, and it
describes the nature of the resulting data. Amplitude calibration is discussed
in detail: a path that utilizes the two loads in the ALMA calibration system as
well as sky measurements is described and applied to commissioning data.
Inspection of a large number of single-dish datasets shows significant
variation in the resulting temperatures, and based on the temperature
distributions we derive quiet-Sun values at disk center of 7300 K at lambda=3
mm and 5900 K at lambda=1.3 mm. These values have statistical uncertainties of
order 100 K, but systematic uncertainties in the temperature scale that may be
significantly larger. Example images are presented from two periods with very
different levels of solar activity. At a resolution of order 25 arcsec, the 1.3
mm wavelength images show temperatures on the disk that vary over about a 2000
K range.Comment: Solar Physics, accepted: 24 pages, 13 figure
Proplyds and Massive Disks in the Orion Nebula Cluster Imaged with CARMA and SMA
[Abridged] We imaged a 2' x 2' region of the Orion Nebula cluster in 1.3 mm
wavelength continuum emission with the recently commissioned Combined Array for
Research in Millimeter Astronomy (CARMA) and with the Submillimeter Array
(SMA). Our mosaics include >250 known near-IR cluster members, of which 36 are
so-called "proplyds" that have been imaged previously with the Hubble Space
Telescope. We detected 40 sources in 1 mm continuum emission, and several of
them are spatially resolved with our observations. Dust masses inferred for
detected sources range from 0.01 to 0.5 Msun, and the average disk mass for
undetected sources is estimated to be ~0.001 Msun, approximately an order of
magnitude smaller than the minimum mass solar nebula. Most stars in the ONC
thus do not appear to currently possess sufficient mass in small dust grains to
form Jupiter-mass (or larger) planets. Comparison with previous results for
younger and older regions indicates that massive disks evolve significantly on
~Myr timescales. We also show that the percentage of stars in Orion surrounded
by disks more massive than ~0.01 Msun is substantially lower than in Taurus,
indicating that environment has an impact on the disk mass distribution.
Finally, we explore potential correlations of disk mass with stellar mass and
location within the cluster.Comment: 45 pages, 11 figures. Accepted for publication in Ap
Australian Opportunities in a Circular Economy for Metals: Findings of the Wealth from Waste Cluster
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