Controlled atmospheres manufactured from technically pure nitrogen and natural gas

1964 ◽  
Vol 6 (9) ◽  
pp. 551-554
Author(s):  
N. A. Titov
Keyword(s):  
Natural Gas ◽  
Pure Nitrogen ◽  
Controlled Atmospheres

A Pure Nitrogen Natural Gas Well

Science ◽  
1942 ◽  
Vol 95 (2461) ◽  
pp. 223-224
Author(s):  
Harold J. Cook
Keyword(s):  
Natural Gas ◽  
Pure Nitrogen ◽  
Gas Well

Ammonia dilution during nitriding and carbonitridingin a fluidized bed of 41CrAlMo7 constructional steel

2019 ◽  
Vol 24 (3) ◽  
pp. 34-41
Author(s):  
Tadeusz Żółciak ◽  
Zbigniew Łataś
Keyword(s):  
Carbon Dioxide ◽  
Natural Gas ◽  
Aluminum Oxide ◽  
Fluidized Bed ◽  
Constant Temperature ◽  
Nitrided Layer ◽  
High Surface ◽  
Surface Hardness ◽  
Constructional Steel ◽  
Pure Nitrogen

Nitriding of 41CrAlMo7 steel was carried out in a fluidized bed of aluminum oxide at a constant temperature of 570oC/4h in ammonia with technical nitrogen or with nitrogen-hydrogen mixture. Carbonitriding was carried out in ammonia with technical nitrogen for two different carbon carriers. In addition, one process was carried out in ammonia with the addition of 5% propane. The influence of diluting ammonia with pure and technical nitrogen upon the hardness and thickness of the nitrided layer was investigated. The hardness and thickness of the carbonitrided layer in ammonia with technical nitrogen and natural gas or carbon dioxide were compared with the parameters of the layer carbonitrided in ammonia and propan. High surface hardness and thickness of the nitrided layer were obtained with the participation of 70% of pure nitrogen or 30% of technical nitrogen in a mixture with ammonia after preliminary oxidation at 350oC/ 30min in air. In case of carbonitriding, the highest hardness and thickness of the nitrided layer were obtained in a mixture of ammonia with and the addition of 5% propane, and the highest thickness of the nitride compound zone in a mixture of ammonia and technical nitrogen with the addition of natural gas or carbon dioxide.

Apparatus for producing pure nitrogen ? hydrogen atmosphere from natural gas

1976 ◽  
Vol 18 (3) ◽  
pp. 268-270
Author(s):  
B. M. �strin ◽  
V. N. Bryzgalin ◽  
V. E. Bakhirev
Keyword(s):  
Natural Gas ◽  
Hydrogen Atmosphere ◽  
Pure Nitrogen

A PURE NITROGEN NATURAL GAS WELL

Science ◽  
1942 ◽  
Vol 95 (2461) ◽  
pp. 223-224
Author(s):  
H. J. COOK
Keyword(s):  
Natural Gas ◽  
Pure Nitrogen ◽  
Gas Well

A Pure Nitrogen Natural Gas Well

Science ◽  
1942 ◽  
Vol 95 (2461) ◽  
pp. 223-224
Author(s):  
Harold J. Cook
Keyword(s):  
Natural Gas ◽  
Pure Nitrogen ◽  
Gas Well

Effects of Ion Beam Milling on Surface Topography

1973 ◽  
Vol 31 ◽  
pp. 84-85
Author(s):  
P.G. Pawar ◽  
P. Duhamel ◽  
G.W. Monk
Keyword(s):  
Surface Topography ◽  
Ion Beam ◽  
Solid Material ◽  
Beam Current ◽  
Atomic Mass ◽  
Micro Milling ◽  
Ion Milling ◽  
Controlled Atmospheres ◽  
Milling Operations ◽  
Sufficient Energy

A beam of ions of mass greater than a few atomic mass units and with sufficient energy can remove atoms from the surface of a solid material at a useful rate. A system used to achieve this purpose under controlled atmospheres is called an ion miliing machine. An ion milling apparatus presently available as IMMI-III with a IMMIAC was used in this investigation. Unless otherwise stated, all the micro milling operations were done with Ar+ at 6kv using a beam current of 100 μA for each of the two guns, with a specimen tilt of 15° from the horizontal plane.It is fairly well established that ion bombardment of the surface of homogeneous materials can produce surface topography which resembles geological erosional features.

Conformation of eukaryotic ribosomal RNAs

1983 ◽  
Vol 41 ◽  
pp. 592-593
Author(s):  
M. Boublik ◽  
G. Thornton ◽  
G. Oostergetel ◽  
J.F. Hainfeld ◽  
J.S. Wall
Keyword(s):  
Molecular Weight ◽  
Mass Measurement ◽  
Carbon Film ◽  
Structural Complexity ◽  
Scanning Transmission Electron Microscope ◽  
Electron Microscopic ◽  
Pure Nitrogen ◽  
Freeze Dried ◽  
Scanning Transmission ◽  
Partially Unfolded

Understanding the structural complexity of ribosomes and their role in protein synthesis requires knowledge of the conformation of their components - rRNAs and proteins. Application of dedicated scanning transmission electron microscope (STEM), electrical discharge of the support carbon film in an atmosphere of pure nitrogen, and determination of the molecular weight of individual rRNAs enabled us to obtain high resolution electron microscopic images of unstained freeze-dried rRNA molecules from BHK cells in a form suitable for evaluation of their 3-D structure. Preliminary values for the molecular weight of 28S RNA from the large and 18S RNA from the small ribosomal subunits as obtained by mass measurement were 1.84 x 106 and 0.97 x 106, respectively. Conformation of rRNAs consists, in general, of alternating segments of intramolecular hairpin stems and single stranded loops in a proportion which depends on their ionic environment, the Mg++ concentration in particular. Molecules of 28S RNA (Fig. 1) and 18S RNA (not shown) obtained by freeze-drying from a solution of 60 mM NH+4 acetate and 2 mM Mg++ acetate, pH 7, appear as partially unfolded coils with compact cores suggesting a high degree of ordered secondary structure.

Microstructural Evolution in Reduced TiO2

1981 ◽  
Vol 39 ◽  
pp. 74-75
Author(s):  
W. T. Donlon ◽  
S. Shinozaki ◽  
E. M. Logothetis ◽  
W. Kaizer
Keyword(s):  
Microstructural Evolution ◽  
Point Defects ◽  
Extended Defects ◽  
Small Deviations ◽  
Controlled Atmospheres ◽  
Limited Solubility ◽  
Thin Foils ◽  
Heat Treated ◽  
Porous Polycrystalline ◽  
Crystallographic Shear

Since point defects have a limited solubility in the rutile (TiO2) lattice, small deviations from stoichiometry are known to produce crystallographic shear (CS) planes which accomodate local variations in composition. The material used in this study was porous polycrystalline TiO2 (60% dense), in the form of 3mm. diameter disks, 1mm thick. Samples were mechanically polished, ion-milled by conventional techniques, and initially examined with the use of a Siemens EM102. The electron transparent thin foils were then heat-treated under controlled atmospheres of CO/CO2 and H2 and reexamined in the same manner.The “as-received” material contained mostly TiO2 grains (∼5μm diameter) which had no extended defects. Several grains however, aid exhibit a structure similar to micro-twinned grains observed in reduced rutile. Lattice fringe images (Fig. 1) of these grains reveal that the adjoining layers are not simply twin related variants of a single TinO2n-1 compound. Rather these layers (100 - 250 Å wide) are alternately comprised of stoichiometric TiO2 (rutile) and reduced TiO2 in the form of Ti8O15, with the Ti8O15 layers on either side of the TiO2 being twin related.

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