Based on strengthening mechanism of microalloy element Nb and productive technology of bar steel,effect of the composition and rolling parameters on the mechanical properties was investigated. The optimal parameters are:w(C_(eq))≥0.39%,w(Nb)=0.02%-0.04% and water-cooling after rolling for slit rolled rebars. For one-strand rolling process,water-cooling is not necessary.
The main meteorological limit factor of forage grass production was precipitation,the thermal productive potential increased by 3 080 kg/hm~2,and the precipitation productive potential reduced by 841 kg/hm~2.The thermal and water did not match well during the period of grass growth,and the really productivity is coming down.
Recursive utility, productive government expenditure and optimal fiscal policy
The fraction of xylanase in most productive strains amounted to 30-50% of the total secreted protein.
This model makes it possible to minimize general productive expenditures that are made up of the expenditures for the storage of components and the penalties for the incomplete supply of finished products.
In our experiments, the inverse orientation stimulated dry matter accumulation by plants and development of productive tillering shoots, as well as increased the shoot-root dry weight ratio.
The functional roles of phenylalanine and ATP in productive binding of the tRNAPhe acceptor end have been studied by photoaffinity labeling (cross-linking) of T.