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91.
Maize, soft wheat and barley diets were compiled to have similar crude fibre (CF) concentration by addition of purified cellulose. Protein-free diets, with purified cellulose included at 60 g kg?1 dry matter (DM) (PF1) and 90 g kg?1 DM (PF2), were formulated. Each of four littermate, male pigs (22 kg liveweight) was surgically modified to create an ileo-rectal anastomosis with complete isolation of the large intestine. Diets were fed, and the ileal digesta, excreted via the anus, were collected. Endogenous amino acid output was higher after feeding PF2 than PF1. The choice of factor for correction of apparent digestibility (AD) to true digestibility (TD) was based upon CF intake of cereal diet. AD of most essential amino acids was greater in wheat than in maize or barley, although AD of lysine in barley (67.1%) was higher than in maize (56.8%) or wheat (63.4%). TD of most essential amino acids was higher for wheat and maize than for barley, although TD of lysine was similar for all cereals. Lysine and threonine were the most poorly digested essential amino acids in all cereals.  相似文献   
92.
Wetlands can collect contaminated runoff from agricultural catchments and retain dissolved and particle-laden pesticides. However, knowledge about the capacity and functioning of wetland systems with respect to the removal of pesticides is very limited. Here we show that stormwater wetlands can efficiently remove pesticides in runoff from vineyard catchments during the period of pesticide application, although flow and hydrochemical conditions of the wetland largely vary over time. During the entire agricultural season, the inflowing load of nine fungicides, six herbicides, one insecticide and four degradation products was 8.039 g whereas the outflowing load was 2.181 g. Removal rates of dissolved loads by the wetland ranged from 39% (simazine) to 100% (cymoxanil, gluphosinate, kresoxim methyl and terbuthylazine). Dimethomorph, diuron, glyphosate, metalaxyl and tetraconazole were more efficiently removed in spring than in summer. More than 88% of the input mass of suspended solids was retained, underscoring the capability of the wetland to trap pesticide-laden particles via sedimentation. Only the insecticide flufenoxuron was frequently detected in the wetland sediments. Our results demonstrate that stormwater wetlands can efficiently remove pesticide mixtures in agricultural runoff during critical periods of pesticide application, although fluctuations in the runoff regime and hydrochemical characteristics can affect the removal rates of individual pesticides.  相似文献   
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A new type of organotin chloride catalyst supported on a highly porous polymer has been prepared by polymerisation of a highly concentrated reverse emulsion the organic phase of which contains several monomers. This polymer‐supported organotin chloride shows a good activity and good stability towards dehalogenation and radical cyclisation.  相似文献   
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