Insecticides Evaluated in Field Tests Against Cotton Insects in Central Texas, 197012

1972 ◽  
Vol 65 (4) ◽  
pp. 1111-1112 ◽  
Author(s):  
C. B. Cowan ◽  
J. W. Davis
Keyword(s):  
Field Tests ◽  
Central Texas ◽  
Cotton Insects

BEAM FORMING WITH VIBRATOR ARRAYS

Geophysics ◽  
1977 ◽  
Vol 42 (7) ◽  
pp. 1321-1338 ◽  
Author(s):  
M. E. Arnold
Keyword(s):  
Time Delays ◽  
Visual Inspection ◽  
Random Noise ◽  
Field Tests ◽  
Beam Forming ◽  
Sound Waves ◽  
North Central ◽  
Linear Arrays ◽  
Central Texas ◽  
Theoretical Advantage

Seismic field tests conducted near Tulsa, Oklahoma, and the Handy area in north‐central Texas used linear arrays of vibrators to concentrate sound waves into a beam, which is directed vertically when all vibrators operate in‐phase or at an angle from the vertical when relative time delays are introduced to each vibrator. The sound wave directivity was verified in the Tulsa area by recordings from subsurface seismometers, and at the same time reflection enhancement by wave beaming was exhibited from surface seismometers. Visual inspection and statistical analysis of reflection continuity indicated that it makes no difference in the Handy area whether beam‐forming techniques are used in the field or are applied later in processing. This result was anticipated, since previous seismic work in the Handy area indicated that the random noise level was low enough to minimize the theoretical advantage of field summing.

Field Tests with Insecticides against Cotton Insects at Tallulah, La., in 19541

1956 ◽  
Vol 49 (1) ◽  
pp. 72-74
Author(s):  
T. R. Pfrimmer ◽  
R. C. Gaines
Keyword(s):  
Field Tests ◽  
Cotton Insects

Architecture of Radiolitid Rudist (Mollusca) Shell-Wall Structures and its Phylogenetic Implications

1975 ◽  
Vol 33 ◽  
pp. 686-687
Author(s):  
David H. Sturm ◽  
Bob F. Perkins
Keyword(s):  
Phylogenetic Relationships ◽  
Outer Wall ◽  
Shell Microstructure ◽  
Shell Wall ◽  
Wall Structures ◽  
Phylogenetic Implications ◽  
Cellular Wall ◽  
Superfamily Analysis ◽  
Central Texas

Each of the seven families of rudists (Mollusca, Bivalvia, Hippuritacea) is characterized by distinctive shell-wall architectures which reflect phylogenetic relationships within the superfamily. Analysis of the complex, calcareous, cellular wall of the attached valve of the radiolite rudist Eoradiolites davidsoni (Hill) from the Comanche Cretaceous of Central Texas indicates that its wall architecture is an elaboration of the simpler monopleurid rudist wall and supports possible radiolite-monopleurid relationships.Several well-preserved specimens of E. davidsoni were sectioned, polished, etched, and carbon and gold coated for SEM examination. Maximum shell microstructure detail was displayed by etching with a 0.7% HC1 solution from 80 to 100 seconds.The shell of E. davidsoni comprises a large, thick-walled, conical, attached valve (AV) and a small, very thin, operculate, free valve (FV) (Fig. 1a). The AV shell is two-layered with a thin inner wall, in which original structures are usually obliterated by recrystallization, and a thick, cellular, outer wall.

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