N/P molar ratios

Station ALOHA (see Figure 23.4 for location information). Three-point running mean observations of N/P molar ratios in (a) total dissolved inorganic plus organic pool, (b) total suspended particulate matter in the upper 0-100 m, (c) in exported particulate matter at 150 m depth, and (d) cycling in nutrient limitation (described in text). Source From Karl, D. M. (2002). Trends in Microbiology 10(9), 410-418. 

Hoffman et al. (18) conducted a parametric study to determine the effect of bacterial strain, N/P molar ratio, the partial pressure of CO2, the coal source and the total reactive surface area on the rate and extent of oxidative dissolution of iron pyrite at a fixed oxygen pressure. The bacterial desulfurization of high pyritic sulfur coal could be achieved in 8 to 12 days for pulp densities upto 20% and particle size of less than 7 um. The most effective strains of T. ferrooxidans were isolated from the natural systems, and the most effective nutrient medium contained low phosphate levels, with an optimal N/P molar ratio of 90 1. 

Shake-Flask Experiments with T ferrooxidans. A limited number of experiments were conducted using T.ferrooxidans to determine the influence of process variables on the rate and extent of pyritic sulfur release from the coal samples in shake-flask experiments using a mechanical shaker. No attempt was made to optimize the mineral salts medium composition since the influence of NtfJ, N/P molar ratio and the nitrogen requirements for the growth of T. ferrooxidans have been thoroughly investigated by other workers (4,7,8,10). A mineral salts medium with the composition described earlier in the Microbial Procedures section was used in all the experiments with T. ferrooxidans. 

Glycerophosphoserine. The water-soluble fraction from the above procedure should contain only sn-glycero-3-phospho-L-serine. Analysis for total lipid P and total N should give an N/P molar ratio of 1.0. In addition to these assays, proof for the presence of serine is very important and can be proven by the analytical procedure(s) described later in this section. A serine (N)/P molar ratio of 1.0 would be expected. 

All 10 PF resins were produced with Ba(OH)2 catalyst for 300 min with varying F/P molar ratio, OH/P wt %, and reaction temperatureffable 1). The resins were stored frozen at -18H until analysis. Molecular species in resol were analyzed by GO after trimethylsilylation of sample with N,0-bis(trimethylsilyl)trifluoracetamide in pyridine[2]. A glass column (3 m x 2 mm I.D.) packed with 3% OV-1 on 100-120 mesh Chromosorh W HP was applied. Injection... 

Alkylation of ammonia with n-propanol over different Raney nickel catalysts (P=2.1 MPa, WHSV=1.5 h K NH3/n-propanol molar ratio)... 

The molar ratio of the III compound to the V compound is typically l/lO.t ] To obtain the desired semiconductor properties, dopants are added such as zinc (from diethyl zinc) or magnesium (from bis(cyclopentadienyl) magnesium) for p doping, and silicon (from silane) or selenium (from hydrogen selenide) for n doping. 

The heavy alkaline earth metals Ca, Sr, and Ba react with 2 equivalents of NJ -bis(2,6-diisopropylphenyl)formamidine in the presence of bis(pentafluorophenyl)-mercury to afford the bis(formamidinato) species as THF adducts in good to moderate yield (Scheme 23). When the same reactions are carried out in a 1 1 molar ratio, N-p-tetrafluorophenyl-N,N -bis(2,6-diisopropylphenyl)formamidine is isolated as the sole product in all cases (Scheme 23). Other substituted N -bis(aryl)formamidinate complexes of the heavy alkaline earth metals were synthesized accordingly. ... 

The above selectivities are affected by changes in the molar ratio between the guests and between guest and host in the solution mixture. They show, however, consistent trends. Qualitatively similar results of guest selectivity were obtained with N,N -bis(tri-p-tolylmethyl)urea and a number of related hosts47. Additional experiments using ureas substituted with chiral spacers are readily envisioned. 

FIGURE 16.9 Model fits at the standard process conditions (T = 230°C, P = 20 bar, H2/CO feed molar ratio = 2.1, GHSV = 5,000 cm3(STP)/h/gcat) in terms of n-paraffins, a-olefins, and total hydrocarbons. 

Basset and co-workers (91) found that amino olefins such as allyl amine and the /V.N-dimethyl derivative failed to undergo metathesis, but that unsaturated quaternary ammonium salts were active at 25°C with zero-valent tungsten and molybdenum catalysts when activated with molecular oxygen. Molar ratios of olefin/(mesitylene)W(CO)3/C2H5AlCl2/02 and olefin/Mo(NO)2Cl2[P(Ph)3]/C2H5AlCl2 were 20/1/24/80 and 20/1/24, respectively. Yields were in the 8-23% range. 

Depending on the molar ratio, the reactions of p-phenylenediamines and EMME gave N-(4-aminophenyl)aminomethylenemalonates (167) (86-EUP174832) or l,4-bis(aminomethyIenemalonates) (168) (49JCS1017 86-EUP174832). 

A simplified conceptualization of oceanic DOM pools based on a two-pool model showing carbon concentrations and elemental C N P ratios of the DOM pools. In reality, the reactivity of DOM probably spans a continuum that is presented herein as two pools, labile and refractory, for the purposes of simplification. Molar elemental ratios are in the format of C N P. Source-. From Hopkinson, C. S., and J. J. Vallino (2005). Nature 433, 142-145. 

An alternative route to heterocycles of type 5 is the reaction of Si Ni with trivalent phosphorus compounds containing P-Cl bonds (16). For example, the reaction of Ph2PCl with Sl,N in a 3 1 molar ratio in CH3CN for 3h at reflux produces an 83% yield of (Ph2PU)2NSCl as moisture-sensitive, pale yellow crystals. 

The reactions of o-, m-, and p-tritolylphosphines (L) with [Mo(CO)g] and [W(CO)6] under a variety of conditions of temperature, u.v. irradiation, and molar ratios have been investigated. The products obtained were of the general formula [M(CO)5L] and cis- and trans-[M(CO)4,L2], and their i.r. and n.m.r. spectra showed interesting trends for variation of the ligands. In addition, the novel derivatives [(n-L)M(CO)3] were obtained with o-tritolylphosphine and characterized by their i.r., n.m.r., and mass spectra. The reactions of... 

Miller et al., 1989 n = 6 children n = 3 n — 3 Age range 11-17 years 250 mg Ca as CCM enriched with tracer in form of chewable tablets Stable dual isotope tracers used to quantify CaAbs in urine and serum. Comparison of CCM chewable versus CCM swallowable supplements and CaCOa from data collected previously in same subjects Based on urinary excretion which correlated with serum data (r = 0.85) x SD% CaAbs from chewable CCM for molar ratio 6 2 3 (41.4 8.2%) > swallowable CCM for molar ratio 5 1 1 (39.5 10.6%) > CaCOa (26.7 7.8%) Chewable CCM > CaCOa (p =. 047) and swallowable CCM > CaCO (p =. 094)... 

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