Nitrogen Type

Respiratory protective devices - Self-contained closed-circuit breathing apparatus, compressed oxygen or compressed oxygen-nitrogen type. Requirements, testing, marking. Supersedes BS 7170 1990 and BS EN 145-2 1993... 

Our current ionization and tautomer model encodes biased and balanced equilibria with 108 and 35 rules respectively. Extensive use is made of atom typing to specify chemistry in as generic a manner as possible, which reduces the number of rules required, for example, a number of heteroaromatic nitrogen types, including selected 2-aminopyridines and imidazoles, are aggregated into a definition of bases with pK ... 

Aromatic nitrogen (Type 2) Delocalized TYPE 2 fragments Potential interact, 3.69 used see text... 

Chelate nitrogen type ligands (i) Chelate imine-type ligands Cu(phen)3](C104)2 (196)... 

Our first study of reaction (342) kinetics (124) was done in a flow system under atmospheric pressure at 400, 450, and 500°C on a Fe304 catalyst without any additions and also on a mixed oxide catalyst of the nitrogen type, the active component of which is Fe304. 

Nitrogen Concentrates. Table III lists the recovery of the heavy oil nitrogen in the two Florisil concentrates and also the concentration of nitrogen types in each of these two concentrates. The weak base and very weak base types are determined by nonaqueous potentiometric... 

Recovery (Wt % of Nitrogen in the Heavy Oil) Nitrogen Type (Wt %of Nitrogen in Concentrate) ... 

Table V. Summary of Nitrogen Types in the Very Weak Base Nitrogen Concentrate...

Fig. 12 Asymmetric alkylation of C3 carbon (type 1) and of a side-chain carbon bonding to the P-lactam nitrogen (type 2) E+ X Ar Ui ft V R X Ar E Li -crxiR ...

Phosphorus-nitrogen type Alkali metal thermionic Alkali metal flame detection, RbS04 and KBr at top of flame [406]... 

Phosphorus- nitrogen type Combined RbCI flame thermionic and electrolytic conductivity detector [408]... 

Corrections are applied to 15 structural types (e.g., alcohols/acids selected phenols, nitros, amines, alkyl pyridines, amino acids, PAHs, multi-nitrogen types, etc.). Application and magnitude depend on available MP. 

Previous analysis of Uinta Basin bitumens (6,10) have shown that the predominant nitrogen types are pyrollic, amide, and aromatic nitrogen. Predominant sulfur types are sulfide, sulfoxide, and thiophenic sulfur predominant oxygen types are ketones, phenols, carboxylic acids, and possibly appreciable concentrations of furans. The aromatic (basic) nitrogen is expected to participate in irreversible adsorption on acidcracking catalysts (13) and it could require an increased cat-to-oil ratio. Previous analyses (10) have indicated also that Uinta Basin bitumen is high in naphthenic hydrocarbon and low in free paraffins. This is illustrated by the results given in Table II in which over 60% of the saturates... 

The samples used were a standard Na-A zeolite and five nitrogeneous types of zeolite A, or N-A.(18) The N-A zeolites are siliceous analogues of zeolite A, synthesized with tetramethyl-ammonium cation. The Si Al ratio varied from 0.94 (NaA) to 3.54 for the most siliceous N-A sample.t The ratios were determined by wet chemical analysis, and the structure type and absence of impurity phases were confirmed by X-ray powder diffraction techniques. Adsorption measurements (oxygen, -183°C) showed a zeolite A content of greater than 90%. 

Table IV. Total Nitrogen, Type II Nitrogen, Vanadium and Nickel Contents in Several Residues...

Element Total Nitrogen Type II Total Type II Nitrogen Sulfur Sulfur Vanadium Nickel... 

Compound type analysis was not conducted in this work, but it is instructive to look at some literature results. With respect to heteroatoms, tar sand bitumen and petroleum asphaltenes have been variously reported as containing predominantly polar heteroatoms, principally oxygen types (18) or nonpolar heteroatoms, principally nitrogen types (14). The difference in these reported results apparently relates to the method of analysis in which the former is a direct determination, the latter an indirect determination. 

Saturated Hydro nitrogens (Type formula NnHn+2). Ammonia NH3 Hydrazine (diamide) H2N.NH2 Triazane (prozane) 1J2 N.NH.NH2 Tetrazane(buzane, liydrotetrazane) H2N.NH.NH. NH2. Ammonia and Hydrazine are known in the free state the Triazanes are rather poorly defined as a class, whereas Tetrazanes exhibit a tendency towards instability by undergoing dissociation in solution to yield hydrazyl radicals... 

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