Narrative of Chain cruise #43 : February - August 1964

Originally issued as Reference No. 65-9, series later renamed WHOI-.On CHAIN Cruise 43, 15 February to 21 August 1964, geophysical and geological observations were made in the North Atlantic Ocean, the Mediterranean and Red Seas, and the Western part of the Indian Ocean, along the track Woods Hole - Ceuta (Spanish Africa) - La Spezia - Port Said - Aden - Victoria (Seychelles Islands) - Port Louis (Mauritius) - Victoria (Seychelles Islands) - Port Said - Beirut - La Spezia - Monaco - Plymouth (England) - Woods Hole. This report contains (1) a narrative of the cruise, (2) a list of stations, (3) statements of the scientific objectives of the cruise, (4) a summary of the geological and geophysical observations, (5) end-of-cruise reports on equipment and some phases of the research program, and (6) a selection of bottom photographs. WHOI Ref. No. 64-51 contains a detailed navigational plot of the entire cruise, including soundings and the locations of other observations.This cruise was supported by the National Science Foundation under Grant GP-2370 and Submitted to the Office of Naval Research under Contract Nonr-4029(00) NR 260-101

Crystal structure of bis(triphenylphosphonium) hexabromadigallate(II) in the correct space group: conformational complexity in a heteroethan

Sherpa Romeo green journal. Open access article. Creative Commons Attribution 4.0 License (CC-BY) appliesThe crystal structure of [Ph3PH]2[Ga2Br6], previously described as having a disordered anion in the space group R̄ 3, has been re-determined in the correct space group P̄ 3, where it is fully ordered. Interestingly, two-thirds of the [Ga2Br6]2− dianions have an intermediate conformation with a Br–Ga–Ga–Br torsion angle of 36.91 (1)°, while the remaining is staggered as required from adopting a site with inversion symmetry. In the lattice, [Ph3PH]+ ions lie along the same threefold axes as the dianions and are oriented such that the P–H bond is directed towards a gallium atom. The phosphonium ions lie back-to-back and interact with relatively strong T-interactions between phenyl rings on adjacent cations. DFT calculations at the B3LYP/6–311+G(fd,) level have been used to determine the barriers to rotation in [Ga2X6]2− ions. For X = Cl and X = Br, the barriers are found to be very small, with values of 4.3 and 5.1 kJ mol−1 for the two halogens.Ye

Part I. A continuous configuration hydrophone array for broadband continuous seismic profiling : Part II. A comparison between the responses of a continuous line array and a discrete linear array

The signal-to-noise ratio of towed receivers employed in seismic reflection profiling is significantly improved by using a hydrophone array whose broadband directional response approaches that of a theoretically continuous sensor. Within a broad pass band all secondary lobes of an array of continuous configuration are less sensitive than the main lobe. This design improves upon the directivity and thus the signal-to -noise ratio realized in broadband work by those linear arrays in common use whose transducers are spaced widely compared to the wavelength and duration of transients of acoustical noise projected along the array from all angles of reception. Sensitivity equal to that of the main lobe is developed by the secondary lobes of these commonly used arrays at various frequencies and angles to the array. The 30 -meter arrays of 200 equally-sensitive transducers described here have a broadband response approaching that of a continuous configuration. In order to obtain uniform sensitivity along the array all transducers are calibrated and chosen to be equal in sensitivity within ±0. 4 dB. Long term stability in sensitivity is attained by the use of small, rugged, cylindrical ceramic transducers. The ratio of seismic signal-to-noise from all sources in a 20 to 1000 Hz passband is about+ 6dB while deep-ocean profiling with a 90 k joule sparker at 8 kts in a moderate sea state. The average seismic signal received 1 second after the onset of the bottom reflections during a 0. 5 second period is compared with the average noise received in the same passband for a similar period just prior to the bottom reflections.The Office of Naval Research under Contract Nonr-4029(00), NR 260-101

Instruction manual for Precision Graphic Recorder (PGR)

This manual describes the objectives, design, operation, and maintenance of the Precision Graphic Recorder (PGR), emphasizing its application to echo-sounding. The words "precision graphic recording" describe a method for displaying data by means of successive, precisely-timed rectilinear sweeps of a recording point or "stylus" across a long, moving strip of sensitized paper (Veatch and Smith, 1939, p. 61-63). The recorded data appear as dye-markings, shaded in proportion to signal amplitude along the sweep of the moving recording point.The Bureau of Ships Under Contract NObsr-72521 and Office of Naval Research Under Contract Nonr-1367 (00) (NR-261-102

Ping-through-the-hull 3.5 kHz echo-sounding systems on the research vessels CHAIN, ATLANTIS II, and KNORR

This report documents the 3.5. kHz sounding systems currently in use on Woods Hole research vessels. To help others to install similar facilities, we discuss the history, installation technique, performance and calibrations of our various systems.Prepared for the 0ffice of Naval Research under Contract N00014-74-C-0262; NR 083-004