Nautilus

Natural sensitizers Natural tannins Natural vs synthetic dyes Nature ofinvention Nausea N.S. Nautilus Naval brass... 

The Atomic Energy Commission designated Argonne National Laboratory as the first national lab-oratoi-y on July 1, 1946. Ai-gonne was the lead labora-toiy for nuclear reactors, instrumental in designing and building the first nuclear powered submarine, the USS Nautilus in 19.54, and the first nuclear reactor that completely powered the town of Arco, Idaho, m 1955. 

U.S. Navy latinchs the first titiclcar-pow-ered submarine, U.S.S. Nautilus, the first use of nuclear propulsion. It could cruise 62,500 miles before refueling. 

Moreover, coincidence was measured between resonant bar detectors Nautilus and Explorer [55] in 2001. 

With analogy to electric circuits, a transfer function of the antenna can be calculated and the response of the antenna to an incoming wave obtained. The output signal is usually expressed as antenna cross-section. It is defined as the ratio between the total energy absorbed by the antenna and the incident spectral density function of the incident wave. In the case of Nautilus antenna (2300 kg, 3 x 0.6 m) the cross-section is of the order of 10 25m2 Hz. 

Another innovative aspect of the cryogenics for MiniGRAIL is the cooling down to 77 K with a forced helium flow. Nautilus and Auriga experiments need about 20 days to cool a 2.3 ton A15056 antenna with a surface area of about 6 m2 from room temperature... 

The enthalpy of copper at nitrogen temperature is H77K = 6 J/g, so the total entropy of the sphere will be about 6 x 106 J. The time needed to cool from 77 K down to 4K is of the order of 4h. The total helium consumption from room temperature to 4.2 K would be about 6001. The temperatures reached in a test run are reported in Table 16.2. The expected final sphere temperature is about 20 mK. A comparison of MiniGRAIL and Nautilus cool down is made in Table 16.2. The high power leak on the sphere has been attributed to a time-dependent heat leak caused by the ortho-para conversion (see Section 2.2) of molecular hydrogen present in the copper of the sphere (see Fig. 16.5) (the Nautilus bar instead is made by Al). A similar problem has been found in the cool down of the CUORICINO Frame (see Section 16.6). 

Taking into account the temperature of operation of the detectors and the total mass to cool, a powerful DR (similar to that of the Nautilus Collaboration that cools a 2-ton gravitational antenna) will be needed. 

Pip, E. 1990. Copper, lead and cadmium concentrations in a sample of Lake Winnipeg Anodonta grandis. Nautilus 103 140-142. 

The synthesis can be carried out manually or automated using a Symphony/Multiplex multiple peptide synthesizer or an Argonaut Nautilus. 

Although it is possible to carry out the cleavage of the resins directly on the Nautilus, the delivery of the HMDS standard solution is not sufficiently accurate to allow determination of loadings by H NMR. After removal of the vessels from the reaction module, 1.00 mL of the HMDS solution was carefully added by gas tight syringe. 

The U.S. Navy has had an admirable performance record with its fleet of nuclear surface ships and submarines. There are major differences in the size of the nuclear systems used by the U.S. Navy. The Nautilus submarine used a 60 megawatt reactor which was scaled up to 600, 900 and then over 1000 megawatts for commercial power plants. 

Figure 19.7 Molecular correspondence of the inorganic-organic interface in the nacreous shell layer of Nautilus repertus. (a) Structural relationships between protein sheets, aragonite crystals and chitin fibres, (b) Possible complementarity of Ca binding. (From Mann et al., 1989. Reproduced with permission from John Wiley Sons., Inc.)...

Are you ready for the answer Here is the list of terms sorted in order of beauty as determined by my little survey of scientists and colleagues. The numbers in parentheses indicate the number of times the term was an individual s first choice dancing flames (31), snow crystal (20), mist-covered swamp (17), spiral nautilus shell (10), mossy cavern (5), kaleidoscope image (5), avalanche (4), computer chip (3), seagull s cry (3), tears on a little girl (3), trilobite fossil (2), glimmer of mercury (2), wine (2), asphalt (1). 

Suzuki, T. Fukuta, H. Nagato, H. Umekawa, M. Arginine kinase from Nautilus pompilius, a living fossil. Site-directed mutagenesis studies on the role of amino acid residues in the guanidino specificity region. J. Biol. Chem., 275, 23884-23890 (2000)... 

The carbohydrate components of hard-pieces of invertebrates have been reviewed recently416. Sulfated polysaccharides have been identified as Ca-binding sites of septal nacre from Nautilus pompilius430 This indicates that the site is a sulfated polysaccharide (s), and may be a sulfated, calcium-binding glycoprotein similar to the one isolated from Mercenaria mercenaria414 ... 

Mutvei, H. Ultrastructural relationships between the prismatic and nacreous layers in Nautilus (Cephalopoda). Biomineralisation 4, 81 (1972)... 

Voss-Foucart, M. F. Essais de solubilisation et de fractionnement d une conchioline (nacre murale de Nautilus pompilius, mollusque cephalopode). Comp. Biochem. Physiol. 26, 877 (1968)... 

Crenshaw, M. A., Ristedt, H. The histochemical localization of reactive groups in septal nacre from Nautilus pompilius L. In The mechanisms of mineralization in the invertebrates and plants. Watabe, N., Wilbur, K. M. (eds). The Belle W. Baruch Library in Marine Science, Vol 5, pp. 355. University South Carolina Press 1976... 

N.S. Nautilus -nuclear reactors for [NUCLEAR REACTORS - REACTOR TYPES] (Vol 17)... 

To test this supposition the shell of Nautilus pompilius (mollusc) containing almost 3% organic matter was subjected to pyrolysis at temperatures of up to 500 °C for periods of several hours and days. The experiments were performed under dry conditions and in the presence of distilled water. Sortie of the data are compiled in Table 1. 

Nautilus pompilius deposits a shell composed entirely of aragonite. Experiments95-97 conducted at temperatures between 150° and 900 °C showed the shell aragonite to be stable for a few hours at temperatures of up to 300 °C even under aqueous conditions. Above 300 °C a rapid transformation into calcite was observed... 

Fig. 7. Thermal decomposition rate of shell organic matrix (Nautilus pompilius) at 150 °C in the presence of water. Individual amino acids are reported in residues/1000 and total amino acid concentration in pmol/g numbers on the ordinate are residues/1000 and pmol/g, respectively. Graph on the left is hydrolyzed fraction of total shell material after thermal treatment and graph on the right the unhydrolyzed fraction in the water...

In conclusion thermal degradation studies on Nautilus pompilius indicate that mineralizing matrix and aragonite shell represent a true structural entity. By the sharing of oxygens in protein and mineral lattices we will generate phase boundaries of the type that are present, for instance, in the common clay mineral kaolinite. Here, aluminum octahedra and silica tetrahedra incorporate the same oxygens and hydroxyls, and layers composed of octahedra and tetrahedra arise (Fig. 13). 

Heating experiments on Nautilus shell material (see page 10) indicates a retardation in the rates of thermal decomposition of mineral and organic phase. This has been attributed to the development of a topochemical boundary at the contact protein-mineral. X-ray diffraction analysis gives no evidence for structural alteration of the original aragonite during the thermal treatment up to 200 °C. 

Chemical studies on Nautilus pompilius (a cephalopod) and Mercenaria mercenaria (a clam) indicate that matrix proteins are composed of two structural units (1) a polypeptide with a strong affinity to Ca2+ ions which is soluble in strong CaCl2 solutions, and (2) a high molecular weight protein insoluble in CaCl2 with no affinity to calcium and which is arranged in the form of sheets and layers. 

In Nautilus, the CP has a ratio of GLY ALA SER = 3 2 1. This ratio is identical to that described for the -configuration of silk fibroin, where serine supplants alanine in the layer structure in concentrations up to 15 mole %229. In silk, polypeptide chains are arranged in a zig-zag configuration and so-called pleated sheets are generated (Fig. 26). 

Gregoire, Ch., Gisbourne, C. M., and Hardy, A. Ober experimenteile Diagenese der Nautilus-schale. Beitr. elektronenmikroskop. Dir. Oberfl. 2, 223-238 (1969). 

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