Dark-line laser

In a general way the conclusions arrived at from the discussion of the spectra obtained in 1898 are amply confirmed and extended by the present results. It is now shown that every strong dark line of the solar spectrum exceeding Rowland’s intensity 7 is found in these spectra as a bright line; and the great majority of the bright lines of the flash spectrum, excluding hydrogen and helium lines, coincide with dark lines of intensity not less than 3. Most of the bright arcs of the flash spectrum are well-defined narrow lines admitting of considerable accuracy in the measures, and the present determinations of wave-length indicate that the coincidence of the bright lines with the dark lines is exact within ·05 t. m. for all the well-defined lines.

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Dark-line-resistant diode laser at 0.8 mu m comprising InAlGaAs strained quantum well

IEEE Photonics Technology Letters ◽

10.1109/68.93861 ◽

1991 ◽

Vol 3 (5) ◽

pp. 409-411 ◽

Cited By ~ 36

Author(s):

R.G. Waters ◽

R.J. Dalby ◽

J.A. Baumann ◽

J.L. De Sanctis ◽

A.H. Shepard

Keyword(s):

Quantum Well ◽

Diode Laser ◽

Dark Line ◽

Strained Quantum Well

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Stress‐Induced Dark Line Defect Formation in GaAlAs : Si LED's

Journal of The Electrochemical Society ◽

10.1149/1.2127477 ◽

1981 ◽

Vol 128 (3) ◽

pp. 661-669 ◽

Cited By ~ 10

Author(s):

A. K. Chin ◽

W. C. King ◽

T. J. Leonard ◽

R. J. Roedel ◽

C. L. Zipfel ◽

...

Keyword(s):

Defect Formation ◽

Line Defect ◽

Dark Line

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What causes edge fixation in walking flies?

Journal of Experimental Biology ◽

10.1242/jeb.149.1.281 ◽

1990 ◽

Vol 149 (1) ◽

pp. 281-292 ◽

Cited By ~ 5

Author(s):

D. Osorio ◽

M. V. Srinivasan ◽

R. B. Pinter

Keyword(s):

Visual Field ◽

Lateral Inhibition ◽

Lucilia Cuprina ◽

Dark Side ◽

Dark Line ◽

Dark Region ◽

Dark Background ◽

Mach Band ◽

Eye Region

The orientation of freely walking flies (female Lucilia cuprina) to lines and stripes in a circular arena is described. The following observations were made. 1. The flies walked straight towards a dark line using the frontal eye region, but a pale line on a dark background was only weakly attractive. 2. In bright conditions flies walked in a curved line towards a black-white edge, the path being convex towards the dark side of the border. The curves indicated that the flies were heading for a point about 5–10 degrees to the dark side of the edge. 3. In dim conditions the edge of a dark region was not especially attractive and flies headed towards any point in the dark area. These observations can be accounted for by assuming that the fly walks towards the darkest region in its visual field (scototaxis). In bright conditions the edges of a dark region become more attractive than its centre. This change could be explained if lateral inhibition creates a ‘Mach-band’ effect, making the edges appear darker than the centre. Thus, fixation behaviour in walking Lucilia females seems to be a simple taxis.

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NEW TEXAN MOTHS

The Canadian Entomologist ◽

10.4039/ent85-1 ◽

1876 ◽

Vol 8 (1) ◽

pp. 5-7 ◽

Cited By ~ 1

Author(s):

Leon F. Harvey

Keyword(s):

Dark Line

♂.This species has the fore wings and thorax of a soft brown. The primary is covered by a pea-green patch, which does not reach the margins and is defined outwardly by a narow dark line running once deeply inwardly below vein 2 and slightly opposite the cell. Hind wings light yellowish. It appears to be allied to paenulata Clem., unknown to me, but differs by the shape of the green patch and in its not being bordered with white.

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A Histological Study of the Development of the Scales of the Largemouth Black Bass (Micropterus salmoides)

Journal of Cell Science ◽

10.1242/jcs.s3-94.25.71 ◽

1953 ◽

Vol s3-94 (25) ◽

pp. 71-82

Author(s):

MARY ALICE DIETRICH

Keyword(s):

Micropterus Salmoides ◽

Histological Study ◽

Age Determination ◽

Wide Band ◽

Careful Study ◽

Dark Line ◽

Slowing Down ◽

Dermal Bone ◽

Black Bass ◽

Fibroblastic Cells

1. The scale method of age determination in largemouth black bass, Micropterus salmoides, is valid at least up to and probably including the third year of the fish's life. A more careful study of older fish might reveal that it was valid beyond that point. 2. The annulus in a largemouth black bass is formed by a brief but gradual slowing down of growth and then its quick resumption. The annulus appears as a wide band on the anterior edge of the scale, and as a dark line (circulus) cutting across some inner dark lines (also circuli) on the lateral edges. 3. The scale is mesodermal in origin, and lies in a pocket surrounded by dermal tissue, which in turn is covered externally by a thin layer of epidermis. 4. The bony layer is formed by osteoblastic cells on its outer surface in a manner similar to the formation of dermal bone. Excess bony material is accumulated in ridges or circuli. 5. The fibrillary plate is formed by the fibroblastic cells on its inner surface.

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dark line spectra

Dictionary of Gems and Gemology ◽

10.1007/978-3-540-72816-0_5831 ◽

2009 ◽

pp. 235-235

Keyword(s):

Dark Line

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Waveguides Fabricated in LiNbO3 by Proton Implantation

MRS Proceedings ◽

10.1557/proc-244-323 ◽

1991 ◽

Vol 244 ◽

Cited By ~ 8

Author(s):

P. Moretti ◽

P. Thevenard ◽

K. Wirl ◽

P. Hertel

Keyword(s):

Refractive Index ◽

Refractive Index Profile ◽

Planar Waveguides ◽

Optical Barrier ◽

Dark Line ◽

Wide Range ◽

Ion Energies ◽

Optical Planar Waveguides ◽

Proton Implantation ◽

Mode Spectroscopy

ABSTRACTOptical planar waveguides, with a controllable thickness in a very wide range, typically from 3 to 20 μm, can be fabricated by thermally controlled proton implantation in LiNbO3. In the nuclear stopping region at the end of the ion's tracks a sufficient decrease in refractive index is obtained, thus forming an adequate optical barrier. The mode confinement was investigated by dark line mode spectroscopy, and the refractive index profiles were reconstructed. The effects of different ion fluences and ion energies in the Mev range on the refractive index profile at 300 K have been investigated.

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Native Point Defect Densities and Dark Line Defects in ZnSe

MRS Proceedings ◽

10.1557/proc-408-503 ◽

1995 ◽

Vol 408 ◽

Author(s):

M. A. Berding ◽

A. Sher ◽

M. Van Schilfgaarde

Keyword(s):

Free Energy ◽

Point Defect ◽

Defect Formation ◽

Local Density ◽

Full Potential ◽

Nonradiative Recombination ◽

Dark Line ◽

Frenkel Defect ◽

Native Point Defect ◽

Defect Densities

AbstractNative point defect densities (including vacancies, antisites and interstitials) in ZnSe are calculated using a quasichemical formalism, including both vibrational and electronic contributions to the defect free energy. The electronic contribution to the defect formation free energy is calculated using the self-consistent first-principles full-potential linearized muffin-tin orbital (FP-LMTO) method and the local-density approximation (LDA). Gradient corrections are included so that absolute reference to zinc atoms in the vapor phase can be made. We find that the Frenkel defect formation energy is ∼0.3 eV lower at a stacking fault than in the bulk lattice. Nonradiative-recombination-induced Frenkel defect generation at stacking faults is proposed as a mechanism responsible for the limited device lifetimes.

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