An experiment was conducted to study the effects of seedling age on theil ability to harden, and to determine whether cultivar x seedling age interaction could be identified for frost resistance. In the present study, 6-to 24-d-old alfalfa (Medicago sativaL.) seedlings were significantly more freezing-tolerant after cold-hardening than unhardened controls. Cold-hardened seedlings of age varying from 8 to 24
Contrihution no. 96, regue le 2l Sept. 1976Sept. , acceptie le I dlc. 1976 WrLrEMor, C., Hope, H. J., Par-r-errER, L., Lrncrors, J. rr MrcHnuD, R. 1977 For personal use only.
The correlation between accumulation of linolenic acid in the crowns and roots of winter wheat and its frost hardening at low temperature is indirect. It results from their common requirement for light and low temperature. Light mainly produces energy and carbon reserves. The partial hardening obtained in darkness could be eliminated by preetiolation. The high levels of linolenic acid and frost resistance reached after hardening were maintained for a long time in darkness. The levels of linolenic acid and frost hardiness decreased faster at low temperature in hardened plants after treatment with BASF 13-338, a substituted pyridazinone, than in plants deprived of light. The mode of action of BASF 13-338 is apparently not limited to the inhibition of photosynthesis.
Depending on the process strategy employed, implementation of the biorefinery into an existing pulp and paper mill can often help with process debottlenecking, and enable increased pulp and paper production capacity. Many biorefinery process options also offer the opportunity for bioproducts manufacturing and/or fossil fuel replacement. In this paper, the implementation of two biorefinery processes is examined from the perspective of process debottlenecking at a sodium carbonate-based semichemical pulp and paper mill: (a) lignin precipitation from black liquor by acidification with CO2, and (b) the near-neutral hemicellulose pre-extraction process. The recovery cycle, which includes a Copeland fluidized bed reactor, is the main pulp production bottleneck. Also, pulp quality improvements are possible, which would be achieved by lowering pulp yield.
In Part I of this paper, biorefinery implementation uncertainties were identified and the potential for recovery debottlenecking and maximum paper production attainable were evaluated. In Part II, the economic evaluation and comparison of the selected biorefinery process options in the context of process debottlenecking are presented. The results show that for the case study mill, the hemicellulose pre-extraction process gives opportunity for higher paper production and paper quality improvement. It allows for a production increase of about 20%, as well as lowering the pulp yield from 85% to 79%. With lignin precipitation, it was found that a 15% paper production increase could be possible if the pulp yield is kept constant.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.