Influence of stage of growth at cutting on lucerne production
Abstract A 5-year field trial confirmed that for maximum production lucerne should not be mown frequently when it is growing vigorously. Lucerne repeatedly cut when 20 cm high had 73% of the yield and 115% of the percentage leaf of lucerne cut at early flowering, but continuous mowing at a vigorous growth stage caused severe reduction in lucerne vigour and delayed its recovery growth. This in turn reduced lucerne stand longevity and favoured ingress of weeds.
Yields of protein extracted from irrigated lucerne
Abstract When grown under irrigation in Canterbury, New Zealand, lucerne whole herbage gave total nitrogen yields and leaf and stem percentages which were similar for 5-weekJy (preflowering) harvests and early-flowenng harvests. Yields of extractable protem were also similar. although total herbage dry-matter yields were significantly higher from the longer intervals between harvests (195q kg/ha protein from 17 200 kg/ha dry herbage at preflowenng stage; 1880 kg/ha protem from 21 340 kg/ha dry herbage at early-flowering stage). Extractable protein yielded by herbage cut at 4-weekly intervals to a stubble of 10 em length was similar to that obtained from a crop cut less frequently and to a shorter stubble. Total N yield of lucerne was higher when the crop was grazed at 5-weekly intervals than when it was cut at the same mtervals. The yield of extractable protein from a treatment which was cut at 5-weekly intervals, then stocked. with sheep fed chopped green lucerne ad lib. on the. same area for the subsequ...
Preparation and performance evaluation of swine manure bio-oil modified rubber asphalt binder
Abstract In order to study the effect of the preparation process of swine manure bio-oil modified rubber asphalt binder on the rheological properties of the binder, the matrix asphalt and asphalt rubber were used as the control group, and swine manure bio-oil modified rubber asphalt binders were obtained by three preparation processes. Then the rheological properties of five binders were evaluated by rotational viscosity, DSR, MSCR and BBR tests. The results show that the addition of swine manure bio-oil to asphalt rubber is beneficial to the workability, but cause negative effect on its high temperature performance, fatigue performance and low temperature crack resistance. The preparation method of premixing bio-oil and rubber powder can reduce the degradation of high-temperature performance of asphalt rubber caused by addition of swine manure bio-oil to a certain extent. The fatigue properties of the three bio-binders are close, and the critical temperature is less than 25 °C. The process of premixing bio-oil and rubber powder will increase the creep stiffness and reduce the low-temperature performance. However, the low-temperature performance of the binder obtained by this process is still better than that of the matrix asphalt and can meet the requirements of use. Therefore, it is recommended to use the preparation process of premixing bio-oil and rubber powder to prepare swine manure bio-oil modified asphalt rubber.