Sodium cellulose carbonate (CC-Na) dissolved in 8.5 wt% NaOH/ZnO (100/2–3, w/w) aqueous solution was spun into some acidic
coagulant systems. Diameter of regenerated cellulose fibers obtained was in the range of 15–50μm. Serrated or circular cross sectional views were obtained by controlling salt concentration or acidity in the acid/salt/water
coagulant systems. Velocity ratio of take-up to spinning was controlled up to 4/1 with increasing spinning velocity from 5
to 40 m/min. Skin structure of was developed at lower acidity or higher concentration of coagulants. Fineness, tenacity and
elongation of the regenerated cellulose fibers were in the range of 1.5–27 denier, 1.2–2.2 g/d, and 8–11.3%, respectively.
All of CC-Na and cellulose fibers spun from CC-Na exhibited cellulose II crystalline structure. Crystallinity index was increased
with increasing take-up speed. 相似文献
Abstract Wastewater treatment with reactive filters and recycling the phosphorus (P)‐saturated materials as fertilizers in plant production is a suitable concept for a sustainable society. The objective of the present study was to evaluate the ability of the Hedley P fractionation scheme to separate different P fractions, including inorganic and organic P, in soils and sorbent materials used to reduce the P content of waste water. An additional aim was to determine changes in P fractions after storage for 8 months under different humidity regimes. This was to evaluate whether extractability of P is dependent on storage conditions between sorption of P and the subsequent use of the sorbent materials as P fertilizers. This study is the first one showing that in sorbent materials used for treatment of wastewater, the Hedley fractionation scheme separated Ca phosphates in the HC1 extract from Al and Fe phosphates in the NaOH extract. The different fractions could also be used to characterize soils of different origins, to separate liming treatments, and to approximately document soil P fertility, but could not assess differences in soil P status caused by different P fertilization in a single year. No significant influence of moisture regimes during storage on resin‐exchangeable P was detected. This increases the suitability of the studied sorbent materials for recycling P from wastewater to agricultural crops, because it indicates that plant availability of sorbed P does not change drasticaIly during the studied storage conditions. 相似文献
The effect of three wheat grain treatments on the zootechnical performance (feed intake, milk production and milk fat and protein production) of dairy cattle was studied with 18 Holstein cows in each of two feeding trials (both a 3 × 3 Latin square design). Rolled wheat, NaOH treated wheat and immature wheat ensiled with Graintona-Plus (Vee-lik, Zuienkerke, Belgium) were compared in a ration with fixed DM proportions of wheat, maize silage and prewilted grass silage. The nutritive value of the three wheat treatments was derived from in situ rumen degradability studies and from in vivo digestibility experiments.
In situ rumen incubations showed that NaOH treatment strongly decreased protein and starch degradability of the wheat. Due to that importantly decreased starch degradability NaOH treated wheat may be a source of starch with a reduced risk of rumen acidosis as compared to rolled wheat. On the other hand, due to the ensiling, immature wheat had a very high washable starch fraction, despite the Graintona-Plus treatment. The protein value differed importantly, with the DPI (true protein digested in the small intestine; [Tamminga, S., van Straalen, W.M., Subnel, A.P.J., Meijer, R.G.M., Steg, A., Wever, C.J.G., Blok, M.C., 1994. The Dutch protein evaluation system: the DVE/OEB-system. Livest. Prod. Sci. 40, 139–155]) value being 103, 125 and 76 g/kg DM for rolled, NaOH treated and ensiled wheat, respectively. The RDPB (degraded protein balance; [Tamminga, S., van Straalen, W.M., Subnel, A.P.J., Meijer, R.G.M., Steg, A., Wever, C.J.G., Blok, M.C., 1994. The Dutch protein evaluation system: the DVE/OEB-system. Livest. Prod. Sci. 40, 139–155]) value of the NaOH treated wheat was − 51 vs. − 37 and− 33 g/kg DM for rolled and ensiled wheat. In vivo digestibility trials with Holstein cows indicated that the net energy value of the wheat treatments was not significantly different.
In Trial 1, all diets were formulated to supply 105% of the requirements of DPI and net energy lactation (NEL; [Van Es, A.J.H., 1978. Feed evaluation for ruminants: I. The system in use from May 1977 onwards in the Netherlands. Livest. Prod. Sci. 5, 331–345]) and a safe RDPB level (± 200 g/day). On average 4.6 kg wheat DM was fed daily. Following trial 1, trial 2 was carried out, with the maize silage, grass silage and wheat fed in the same proportions as in trial 1, but fed ad libitum, to compare the intake level of the three diets. In both trials, the NaOH treated wheat resulted in the best performance with importantly increased milk yield and the highest yield of fat and protein corrected milk. Ensiled immature wheat resulted in a significant lower milk production and milk protein yield and in a higher milk fat content. In trial 1, DM-intake of the three groups was comparable due to the experimental design. In trial 2 intake of the cows fed NaOH treated wheat was significantly higher (23.5 vs. 21.1 kg/day for the other two groups). 相似文献
This study investigates the effect of NaOH and NaOCl treatments on chemical composition, morphology and crystalline structure of Agave americana L. fibers. These fibers have been subjected to NaOCl and NaOH alkali treatments at different concentrations.The percentages of lignin and hemicellulose show a decrease with alkaline treatments which, in turn, induces a modification of both morphological and crystalline structures.Unit cell dimensions and crystallite size were more affected with NaOH treatment than NaOCl one. This may result from the mercerisation process which occurs with caustic soda treatment.The observed defibrillization on the treated fiber surface proves the dissolution of the non-cellulosic components present in the fiber cell wall by NaOH and NaOCl treatments. These morphological changes may improve the interaction between matrix and fiber in composites. 相似文献
