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The organomercury reagents PhHgCCl 2 SO 2 Ph, PhHgCBr 2 SO 2 Ph, PhHgCClICO 2 Me, cyclo-C 6 H 11 HgCCl 2 CO 2 Me, PhCH 2 CH 2 HgCCl 2 CO 2 Me, PhHgCHClCO 2 -Et and PhHgCCl 2 CONMe 2 have been prepared and their application as divalent carbon transfer reagents has been examined.

Presented is a mathematical model for the continuous-flow steady-state bacterial culture which permits the experimental determination of carbon transfer rates within the system by use of radioactive tracer techniques. The transfer rates are specific for hydraulic loading rates, feed concentrations, type of organism, and substrate, and were incorporated within the existing theoretical description of the growth kinetics in order to elucidate the yield relationships. The carbon transfer rate of cells to soluble organic substrate was observed to exhibit a minimum value at or near dilution rate D = 0.5 hr.−1. A maximum effective yield coefficient, Y, was observed at the same value of D. At dilution rates greater and less than D = 0.5 hr.−1, the cell–substrate transfer rate increased, and effective yield coefficient was observed to decrease. The former showed increases of 50–200%, and the latter exhibited decreases of the order of 10%. The magnitude of these variations would seem to be significant in industrial fermentation processes which utilize continuous microbiological cultures. In light of these findings, the results of other researchers were shown to exhibit maximum effective yield at similar dilution rates or process loadings.

SUMMARY 14CO2 was fed to the bloom node leaf subtending 30-35-day-old broad bean pods, and the leaf, pod and seeds harvested during 19 hours. An immediate transfer of label from leaf to fruit was observed. During the night, a second peak of activity occurred in the fruit owing to an influx of labelled carbohydrate into the seed, but this was not at the expense of leaf carbon. Possible sources of this carbohydrate are discussed.

Methods for labelling growing plants by exposing them to C14O2 under a cellulose acetate-butyrate canopy have been developed for laboratory and field use. The length of labelling ranged from 2 to 33 days and the C14O2 content of the atmosphere was automatically controlled. This made it possible to measure carbon assimilation by the plants, transfer of photosynthates beneath ground and respiration of the roots.

Estimates of the rate of translocation of carbon, T, from sugar beet leaves were made from simultaneous determinations of CO2 exchange and dry weight change. For an illuminated leaf in a constant environment, T increased to a maximum during the first 2 h and was constant for the next 10 h. On darkening, T decreased rapidly in the first 2 to 4 h to a constant minimal value which could continue for as long as 24 h. The average value of T for nine leaves in the light was 4.2 ± 0.4 mg C dm−2 leaf surface h−1, while in the dark the average value for five leaves over 10 h was 1.2 ± 0.2 mg C dm−2 h−1. Generally T was about three-quarters of the net rate of photosynthetic carbon fixation.

A mass transfer model was developed for the prediction of melting times of various sized steel scrap additions made to stagnant pig iron baths operating below the scrap melting temperature range. it was shown that turbulent natural convection currents set up as a result of carbon transfer from the high carbon bath to the scrap surfaces played an impor,ant role in enhancing melting rates, but that predicted mass transfer coefficients sometimes had to be adjusted to take into account the effects of a shrinking interface.Experimental results obtained for melting rates of steel rods immersed in a 500 lb induction furnace and plant results involving scrap melting in hot metal transfer ladles correlated well with the mass transfer analysis. Resume Un modele fonde sur la theorie du transfert de masse a ete developpe dans le but de predire le temps necessaire a la fusion d'additions de ferrailles de dimensions variees dans des bains de fonte en gueuse. Ces bains n'etaient soumis a aucune agitation et leur...

The 14C incorporation into purine bases of fetal brains was investigated when DL-serine-3-14C, L-histidine-2-14C, or formate-14C was injected intraperitoneally to dams with or without pre-treatment with aminopterin. The radioactivity of 14C in fetal brain tissues was estimated on the 18th day of gestation. On the 11th day of gestation, DL-serine-3-14C, L-histidine-2-14C, or formate-14C was injected to dams intraperitoneally. In the case of aminopterin treatment, aminopterin, 0.076mg/kg, was injected intraperitoneally to dams on the 10th day of gestation. The results in these experimental conditions showed that the 14C incorporation from formate-14C into adenine of fetal brains and that from DL-serine-3-14C into guanine of fetal brains were impaired significantly by aminopterin injection to dams prior to injections of the labeled materials.