Bubble defects of glass were studied by Ruman spectrum, C equivalent of glass raw materials were analyzed by chemical method, and the solubility of sulphur in glass was determined with SC-132 Sulphur Determination.. T...Bubble defects of glass were studied by Ruman spectrum, C equivalent of glass raw materials were analyzed by chemical method, and the solubility of sulphur in glass was determined with SC-132 Sulphur Determination.. Then, the relationship between glass bubble, the redox numbers of glass batch and the solubility of sulphur in float glass were discussed. The way that can improve the quality of float glass was found.展开更多
In ruminant field of digestive research, the appeal to methods of less invasive studies and reproducing the in vivo conditions is essential. The objective of the present study was to determine whether the conditions c...In ruminant field of digestive research, the appeal to methods of less invasive studies and reproducing the in vivo conditions is essential. The objective of the present study was to determine whether the conditions created with the proposed in vitro batch culture was an accurate reproduction of the physico-chemical and fermentative ruminal conditions observed in vivo. Two experiments were conducted to compare ruminal reducing power measured in vitro, i.e. in batch cultures or, in vivo i.e. in live animals: dairy cows at maintenance (Experiment 1) and lactating dairy cows (Experiment 2). In Experiment 1, at the beginning of incubation period, in vitro redox potential (Eh), pH and Clark’s exponent (rH) values were significantly higher than in vivo (+42 mV, +0.25 and +1.9, respectively) whereas volatile fatty acids (VFA) contents were 2.6 fold lower on average. At the end of incubation, Eh, rH values and VFA contents were similar between both methods whereas pH still remained different. In Experiment 2, at the beginning and at the end of incubation period, in vitro Eh, pH and rH values differed significantly than in vivo. As a result, the in vitro method did not provide a tool to evaluate accurately the level of the reducing status of ruminal milieu compared with in vivo measurement. Nonetheless, it provided strong reducing conditions after 8 h of incubation with levels of rH relatively closed to those observed in vivo. In vitro batch culture could be a good alternative to in vivo trials for a screening approach from an ethic and economic point of view in ruminant field of research.展开更多
文摘Bubble defects of glass were studied by Ruman spectrum, C equivalent of glass raw materials were analyzed by chemical method, and the solubility of sulphur in glass was determined with SC-132 Sulphur Determination.. Then, the relationship between glass bubble, the redox numbers of glass batch and the solubility of sulphur in float glass were discussed. The way that can improve the quality of float glass was found.
文摘In ruminant field of digestive research, the appeal to methods of less invasive studies and reproducing the in vivo conditions is essential. The objective of the present study was to determine whether the conditions created with the proposed in vitro batch culture was an accurate reproduction of the physico-chemical and fermentative ruminal conditions observed in vivo. Two experiments were conducted to compare ruminal reducing power measured in vitro, i.e. in batch cultures or, in vivo i.e. in live animals: dairy cows at maintenance (Experiment 1) and lactating dairy cows (Experiment 2). In Experiment 1, at the beginning of incubation period, in vitro redox potential (Eh), pH and Clark’s exponent (rH) values were significantly higher than in vivo (+42 mV, +0.25 and +1.9, respectively) whereas volatile fatty acids (VFA) contents were 2.6 fold lower on average. At the end of incubation, Eh, rH values and VFA contents were similar between both methods whereas pH still remained different. In Experiment 2, at the beginning and at the end of incubation period, in vitro Eh, pH and rH values differed significantly than in vivo. As a result, the in vitro method did not provide a tool to evaluate accurately the level of the reducing status of ruminal milieu compared with in vivo measurement. Nonetheless, it provided strong reducing conditions after 8 h of incubation with levels of rH relatively closed to those observed in vivo. In vitro batch culture could be a good alternative to in vivo trials for a screening approach from an ethic and economic point of view in ruminant field of research.