The reactions pertaining to zinc-silver and cadmium-silver batteries Quarterly report

Electrochemical oxidation of zinc, thermal decomposition of silver oxide, and solubility determinations of silver oxides in potassium hydroxide

The reactions pertaining to zinc-silver and cadmium-silver batteries First quarterly report

Zinc precipitates and thermogravimetric studies of silver oxide for zinc-silver and cadmium-zinc batterie

Investigation of electrode materials for alkaline batteries

A number of amalgam electrode systems were investigated for possible use as high rate anodes and cathodes. The systems examined include: lithium, sodium, and potassium in Group 1, magnesium, calcium, and barium in Group 2, aluminum in Group 3, lead in Group 4, copper in Group 1b, and zinc and cadmium in Group 2b. The K(Hg) and Na(Hg) anodes in 10 VF and 15 VF (an unambiguous expression of concentration that indicates the number of formula weights of solute dissolved in a liter of solution) hydroxide solutions have proven satisfactory; some of these have produced current densities of more than 8 A/sq cm. None of the amalgam cathodes have approached this performance although the TI(Hg) has delivered 1 A/sq cm. Se(Hg) and Te(Hg) cathodes have given very stable discharges. Zn(Hg) and Cd(Hg) electrodes did not show good high rate characteristics, 200 to 300 mA/sq cm being about the maximum current densities obtainable. Both anodes are charged through a two-step process in which M(Hg) is first formed electrochemically and subsequently reduces Zn(II or Cd(II) to form the corresponding amalgam. The second step is extremely rapid for zinc and very slow for cadmium

Improving green manure quality with phosphate rocks in Ontario Canada

Phosphate rock (PR) was applied to one conventional and two organic dairy fields and planted with buckwheat (Fagopyrum esculentum) as a green manure crop. In total, five types of PR were applied at three application rates in order to determine the yield, concentration of P in the aboveground tissue and the P uptake of buckwheat. It was found that PR of relatively high carbonate substitution and small particle diameter could increase buckwheat tissue concentrations to a quality such that mineralization of the buckwheat mulch could occur. Buckwheat mulch and residual PR increased soil P flux as determined by anion exchange membranes in situ in the following spring. This provides evidence that buckwheat of high P quality has the potential to supply P to a subsequent crop

Differences in soil microbial communities in organic and conventional management systems alter soil nutrient dynamics

Non-Peer Reviewe

Nitrogen supply from belowground residues of lentil and wheat to a subsequent wheat crop

Non-Peer ReviewedLentil (Lens culinaris) plants can form an association with rhizobia and thereby biologically fix much of the nitrogen (N) required for their growth. This not only reduces the need for expensive N fertilizer when the lentil crop is grown, but there is a potential to contribute a net increment of N to the soil that can be utilized by the subsequent crop. However, estimating this net increment of N remains a challenge, because of the difficulty in estimating the amount of root and root-derived N. The purpose of this greenhouse study was to quantify the belowground N (BGN) of lentil and wheat (Triticum aestivum) using shoot 15N labeling and to trace the 15N from BGN into subsequently grown wheat plants. Belowground N comprised 34 and 51 % of total plant N in lentil and wheat, respectively. Biomass production and N uptake by wheat grown on lentil belowground residues (BGR) were 49 and 14 % higher than wheat grown on wheat BGR. Moreover, a higher proportion of added 15N from lentil BGN was recovered in the succeeding wheat crop, indicating that lentil BGN was more readily mineralized than wheat BGN. The disproportionately high increase in yield vs. N uptake for wheat grown on lentil BGR, however, indicates that non-N factors also contributed to the increase in wheat yield. This study highlights the importance of including estimates of BGN when evaluating the positive effects of including lentil crops in rotation with cereals

Determining soil nitrogen (N) processes using enzymology in response to varying N treatments across four diverse Brassica napus (canola) lines

Non-Peer ReviewedNitrogen (N) is an important plant nutrient, and it is the primary constituent of plant nucleotides and proteins, but it is usually the most limiting nutrient in the soil. Improving N use efficiency in agricultural crops has become an important goal in sustainable agriculture. Accordingly, understanding enzymes involved in N reactions is increasingly critical as they are important in controlling N in the environment. The objective of this study is to determine N transformation after varying rates of urea fertilizer is applied to a field; and how N transformation may differ between diverse Brassica napus L. (canola) lines. Two diverse B. napus parent lines and two hybrid lines were grown on Dark Brown Chernozemic soil in Saskatchewan, Canada. Root-associated soils were collected from each line at bolting and flowering, and analyzed for urease and ammonium oxidation enzymes, as well, soil nitrate and ammonium content was determined. Both urease and ammonium oxidation enzyme results showed significant differences between B. napus growth stages (bolting and flowering), and N fertilizer rate after mixed effect models were used to analyze the results. We predict that both nitrate-N and ammonium-N will have significant differences between the canola lines and N rate application. Mixed effect analyses will be used to analyze soil nitrate-N and ammonium-N, with regards to canola line differences, and growth stage differences, and N fertilizer rate differences. By characterizing soil N transformations, this research will advance our knowledge in improving N availability for B. napus lines

Nitrogen cycling in root associated soils at bolting, flowering and seed pod filling across eight diverse Brassica napus (canola) genotypes

Non-Peer ReviewedNitrogen (N) mineralization and nitrification can be used predict the amount of N that is available to crops. Brassica napus L. (canola) production is N intensive; therefore, to improve and sustain yields, a better understanding of N cycling patterns for fertilization application is needed. The objective of this study is to examine N cycling after urea fertilization at the three major canola growth stages: bolting, flowering and seed pod filling; and how N cycling may differ between diverse canola lines grown in different soil types. Eight diverse B. napus lines were grown on Dark Brown Chernozemic soil and Black Chernozemic soil in Saskatchewan, Canada. Root-associated soils were collected from each line at bolting, flowering and seed pod filling, and this soil was analyzed for potential nitrification and mineralization, as well as soil nitrate and ammonium content. We predict that potential nitrification will be higher during the bolting and flowering stages of canola growth because the urea fertilizer that was applied to the field would have been converted to nitrate-N, which is plant available. We predict that potential mineralization will be higher during flowering and seed pod filling, because the demand for N to make protein-rich seeds is high enough to deplete much of the inorganic fertilizer N. We also predict that both nitrate-N and ammonium-N will decrease over the growing season, with significant differences between the canola lines and the soil environments. Mixed effect analyses and ANOVA will be used to analyze N cycling in the soil in relation to soil type differences, canola line differences, and growth stage differences. By characterizing soil N processes, this research will advance efforts to understand and improve N uptake for B. napus lines

Microbial Metropolis: Understanding how legume pasture systems interact with soil microbial communities, and subsequent greenhouse gas emissions

Non-Peer ReviewedCattle producers may graze animals on mixed pastures of non-bloat legumes and grasses. This approach can increase dietary protein uptake, improve animal value, and reduce cattle methane emissions by decreasing pasture bloat. The introduction of legumes to a grass pasture can also affect greenhouse gas (GHG) fluxes from the soil by shifting the structure of the microbial communities responsible for nitrous oxide (N2O) emissions and methane consumption, and by altering mineralization rates and soil nutrient content. Two novel forage legume-grass mixes and a grass-alfalfa control were sampled throughout the 2017 and 2018 grazing seasons and analyzed for microbial community structure, nutrient cycling rates, as well as for N2O and methane GHG fluxes. Results suggest microbial community structure, rather than microbial abundance, as one factor regulating GHG emissions. Reduced phosphorous and nitrogen supply rates were key factors limiting microbial abundance, and communities experiencing these environmental stressors were correlated with reduced N2O fluxes. Increasing microbial abundance in response to substrate availability results in depletion of soil phosphorous and nitrogen. This in turn upregulates the carbon and nitrogen cycling activities of communities. Nitrogen and soil moisture content were correlated with increasing nitrous oxide emissions, suggesting that denitrification processes are the major contributor to pasture N2O emissions. In addition, decreasing moisture increased methane consumption, providing a partial sink for cattle-derived methane emissions. Sainfoin treatments had lower cumulative methane consumption when compared to cicer milkvetch and control treatments. Further analysis suggests that different interactions between environmental factors may be involved in shaping microbial communities within each legume treatment, and that local environmental conditions at each sampling point were more important than plant cover treatments in determining daily GHG fluxes. Understanding the microbial processes at play when considering net GHG emissions within a pasture system will contribute to the future sustainability of beef production systems