Background Reduction of the particle size of corn increases energy digestibility and concentrations of digestible and metabolizable energy.Pelleting may also reduce particle size of grain,but it is not known if there ...Background Reduction of the particle size of corn increases energy digestibility and concentrations of digestible and metabolizable energy.Pelleting may also reduce particle size of grain,but it is not known if there are interactions between particle size reduction and pelleting.The objective of this experiment was to test the hypothesis that particle size reduction and pelleting,separately or in combination,increase N balance,apparent total tract digestibility(ATTD)of fiber and fat,and net energy(NE)in corn-soybean meal diets fed to group-housed pigs.Methods Six corn-soybean meal-based diets were used in a 3×2 factorial design with 3 particle sizes of corn(i.e.,700,500,or 300μm)and 2 diet forms(i.e.,meal or pelleted).Pigs were allowed ad libitum access to feed and water.Twenty-four castrated male pigs(initial weight:29.52 kg;standard diviation:1.40)were allotted to the 6 diets using a 6×6 Latin square design with 6 calorimeter chambers(i.e.,4 pigs/chamber)and 6 periods.Oxygen consumption and CO_(2)and CH_(4)productions were measured during fed and fasting states and fecal and urine samples were collected.Results Regardless of particle size of corn,the ATTD of gross energy(GE),N,and acid-hydrolyzed ether extract(AEE),and the concentration of NE were greater(P<0.05)in pelleted diets than in meal diets.Regardless of diet form,the ATTD of GE,N,and AEE,and the concentration of NE were increased(linear;P<0.05)by reducing the particle size of corn,but the increase was greater in meal diets than in pelleted diets(interaction;P<0.05).Conclusions Both pelleting and reduction of corn particle size increased nutrient digestibility and NE,but increases were greater in meal diets than in pelleted diets.展开更多
Ultrasonic waves have a lot of use in the particle surface cleaning.As flotation is one of the methods associated with surface properties,this paper investigates the effect of these waves on performance,particle size,...Ultrasonic waves have a lot of use in the particle surface cleaning.As flotation is one of the methods associated with surface properties,this paper investigates the effect of these waves on performance,particle size,reagents,and feed ash content in coal flotation.To accomplish this goal,coal samples in three size fractions,including coarse(-800 to+400μm),medium(-400 to+100 μm)and fine(-100μm)with various feed ash content.The flotation experiments were evaluated by process indexes such as yield,combustible recovery,and selectivity index.The results indicated the increasing of yield.The increasing was significant in medium size.Furthermore,the results showed that in presence of ultrasonic waves,the collector and frother consumption decreased.And also,applying ultrasonic waves would result more combustible recovery and selectivity index.The ash selectivity index had the highest impact for high feed ash content.展开更多
Background: In rumen fermentation, fumaric acid(FA) could competitively utilize hydrogen with methanogenesis to enhance propionate production and suppress methane emission, but both effects were diet-dependent. This s...Background: In rumen fermentation, fumaric acid(FA) could competitively utilize hydrogen with methanogenesis to enhance propionate production and suppress methane emission, but both effects were diet-dependent. This study aimed to explore the effects of FA supplementation on methanogenesis and rumen fermentation in goats fed diets varying in forage and concentrate particle size.Methods: Four rumen-cannulated goats were used in a 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments: low or high ratio of forage particle size: concentrate particle size(Fps:Cps), without or with FA supplementation(24 g/d). Fps:Cps was higher in the diet with chopped alfalfa hay plus ground corn than in that with ground alfalfa hay plus crushed corn.Results: Both increasing dietary Fps:Cps and FA supplementation shifted ruminal volatile fatty acid(VFA) patterns toward more propionate and less acetate in goats. An interaction between dietary Fps:Cps and FA supplementation was observed for the ratio of acetate to propionate(A:P), which was more predominant when FA was supplemented in the low-Fps:Cps diet. Methane production was reduced by FA, and the reduction was larger in the low-Fps:Cps diet(31.72%) than in the high-Fps:Cps diet(17.91%). Fumaric acid decreased ruminal total VFA concentration and increased ruminal p H. No difference was found in ruminal DM degradation of concentrate or alfalfa hay by dietary Fps:Cps or FA. Goats presented a lower ruminal methanogen abundance with FA supplementation and a higher B. fibrisolvens abundance with high dietary Fps:Cps.Conclusions: Adjusting dietary Fps:Cps is an alternative dietary model for studying diet-dependent effects without changing dietary chemical composition. Fumaric acid supplementation in the low-Fps:Cps diet showed greater responses in methane mitigation and propionate increase.展开更多
This study was conducted to evaluate the effects of feed form(mash and crumble-pellet) and feed particle size(fine, medium and coarse) on growth performance, carcass characteristics and digestive tract development of ...This study was conducted to evaluate the effects of feed form(mash and crumble-pellet) and feed particle size(fine, medium and coarse) on growth performance, carcass characteristics and digestive tract development of broilers. A total of 1,152 one day-old Ross 308 mixed-sex broilers were used in a factorial arrangement(2×3) based on a completely randomized design with six replicates of 32 birds each.Higher average daily gain(ADG) and average daily feed intake(ADFI) were observed(P < 0.01) for birds fed the crumble-pellet diets(CPD) than for those fed the mash diets(MD) during starter, grower and the entire experiment period. From d 1 to 40, birds fed CPD had a higher(P < 0.01) body weight(BW) than those fed MD. Birds fed CPD had a lower(P < 0.01) feed:gain ratio(F:G) during the starter phase than those fed MD. Medium or coarse particle size increased(P < 0.01) ADG and ADFI during the starter phase, but birds fed fine particle size diets had lower(P < 0.01) F:G during the grower phase. In MD,medium and coarse particle sizes resulted in higher(P < 0.05) BW, ADG and ADFI than fine particle size during the whole experiment. In CPD, particle size had no significant effect on growth performance, as indicated by a feed form × particle size interaction(P < 0.05). At 41 days of age, ten birds per treatment were randomly selected and killed for slaughter yields and digestive tract characteristics determination.It was shown that particle size and feed form alone had no significant effect on slaughter yields, so changes was the feed form × particle size interaction. The relative empty weight of the gizzard was greater(P < 0.01) and the relative length of the ileum was longer(P < 0.05) in birds fed MD than in those fed CPD. Overall, CPD improved growth performance during the entire period of the study with effects being less evident during the finisher phase than during the starter and grower phases, and the effect of feed particle size varied depending on feed form.展开更多
Modern industrial technologies call for the development of novel materials with improved surface properties, lower costs and environmentally suitable processes. Plasma spray coating process has become a subject of int...Modern industrial technologies call for the development of novel materials with improved surface properties, lower costs and environmentally suitable processes. Plasma spray coating process has become a subject of intense research which attempts to create functional layers on the surface is obviously the most economical way to provide high per- formance to machinery and industrial equipments. The present work aims at developing and studying the industrial wastes (Flay-ash, Quartz and illmenite composite mixture) as the coating material, which is to be deposited on Mild Steel and Copper substrates. To study and evaluate Coating deposition efficiency, artificial neural network analysis (ANN) technique is used. By this quality control technique, it is sufficient to describe approximation complex of in- ter-relationships of operating parameters in atmospheric plasma spray process. ANN technique helps in saving time and resources for experimental trials. The aim of this work is to outline a procedure for selecting an appropriate input vec- tors in ANN coating efficiency models, based on statistical pre-processing of the experimental data set. This methodology can provide deep understanding of various co-relationships across multiple scales of length and time, which could be essential for improvement of product and process performance. The deposition efficiency of coatings has a strong dependence on input power level, particle size of the feed material, powder feed rate and torch to substrate distance. ANN experimental results indicate that the projection network has good generalization capability to optimize the deposition efficiency, when an appropriate size of training set and network is utilized.展开更多
基金The financial support from the National Pork Board,Des Moines,IA,USA,is greatly appreciated。
文摘Background Reduction of the particle size of corn increases energy digestibility and concentrations of digestible and metabolizable energy.Pelleting may also reduce particle size of grain,but it is not known if there are interactions between particle size reduction and pelleting.The objective of this experiment was to test the hypothesis that particle size reduction and pelleting,separately or in combination,increase N balance,apparent total tract digestibility(ATTD)of fiber and fat,and net energy(NE)in corn-soybean meal diets fed to group-housed pigs.Methods Six corn-soybean meal-based diets were used in a 3×2 factorial design with 3 particle sizes of corn(i.e.,700,500,or 300μm)and 2 diet forms(i.e.,meal or pelleted).Pigs were allowed ad libitum access to feed and water.Twenty-four castrated male pigs(initial weight:29.52 kg;standard diviation:1.40)were allotted to the 6 diets using a 6×6 Latin square design with 6 calorimeter chambers(i.e.,4 pigs/chamber)and 6 periods.Oxygen consumption and CO_(2)and CH_(4)productions were measured during fed and fasting states and fecal and urine samples were collected.Results Regardless of particle size of corn,the ATTD of gross energy(GE),N,and acid-hydrolyzed ether extract(AEE),and the concentration of NE were greater(P<0.05)in pelleted diets than in meal diets.Regardless of diet form,the ATTD of GE,N,and AEE,and the concentration of NE were increased(linear;P<0.05)by reducing the particle size of corn,but the increase was greater in meal diets than in pelleted diets(interaction;P<0.05).Conclusions Both pelleting and reduction of corn particle size increased nutrient digestibility and NE,but increases were greater in meal diets than in pelleted diets.
文摘Ultrasonic waves have a lot of use in the particle surface cleaning.As flotation is one of the methods associated with surface properties,this paper investigates the effect of these waves on performance,particle size,reagents,and feed ash content in coal flotation.To accomplish this goal,coal samples in three size fractions,including coarse(-800 to+400μm),medium(-400 to+100 μm)and fine(-100μm)with various feed ash content.The flotation experiments were evaluated by process indexes such as yield,combustible recovery,and selectivity index.The results indicated the increasing of yield.The increasing was significant in medium size.Furthermore,the results showed that in presence of ultrasonic waves,the collector and frother consumption decreased.And also,applying ultrasonic waves would result more combustible recovery and selectivity index.The ash selectivity index had the highest impact for high feed ash content.
基金supported by the National Key Research and Development Program of China(2017YFD0500500)Key Research and Development Program of Shaanxi Province(2017ZDXM-NY-086)
文摘Background: In rumen fermentation, fumaric acid(FA) could competitively utilize hydrogen with methanogenesis to enhance propionate production and suppress methane emission, but both effects were diet-dependent. This study aimed to explore the effects of FA supplementation on methanogenesis and rumen fermentation in goats fed diets varying in forage and concentrate particle size.Methods: Four rumen-cannulated goats were used in a 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments: low or high ratio of forage particle size: concentrate particle size(Fps:Cps), without or with FA supplementation(24 g/d). Fps:Cps was higher in the diet with chopped alfalfa hay plus ground corn than in that with ground alfalfa hay plus crushed corn.Results: Both increasing dietary Fps:Cps and FA supplementation shifted ruminal volatile fatty acid(VFA) patterns toward more propionate and less acetate in goats. An interaction between dietary Fps:Cps and FA supplementation was observed for the ratio of acetate to propionate(A:P), which was more predominant when FA was supplemented in the low-Fps:Cps diet. Methane production was reduced by FA, and the reduction was larger in the low-Fps:Cps diet(31.72%) than in the high-Fps:Cps diet(17.91%). Fumaric acid decreased ruminal total VFA concentration and increased ruminal p H. No difference was found in ruminal DM degradation of concentrate or alfalfa hay by dietary Fps:Cps or FA. Goats presented a lower ruminal methanogen abundance with FA supplementation and a higher B. fibrisolvens abundance with high dietary Fps:Cps.Conclusions: Adjusting dietary Fps:Cps is an alternative dietary model for studying diet-dependent effects without changing dietary chemical composition. Fumaric acid supplementation in the low-Fps:Cps diet showed greater responses in methane mitigation and propionate increase.
文摘This study was conducted to evaluate the effects of feed form(mash and crumble-pellet) and feed particle size(fine, medium and coarse) on growth performance, carcass characteristics and digestive tract development of broilers. A total of 1,152 one day-old Ross 308 mixed-sex broilers were used in a factorial arrangement(2×3) based on a completely randomized design with six replicates of 32 birds each.Higher average daily gain(ADG) and average daily feed intake(ADFI) were observed(P < 0.01) for birds fed the crumble-pellet diets(CPD) than for those fed the mash diets(MD) during starter, grower and the entire experiment period. From d 1 to 40, birds fed CPD had a higher(P < 0.01) body weight(BW) than those fed MD. Birds fed CPD had a lower(P < 0.01) feed:gain ratio(F:G) during the starter phase than those fed MD. Medium or coarse particle size increased(P < 0.01) ADG and ADFI during the starter phase, but birds fed fine particle size diets had lower(P < 0.01) F:G during the grower phase. In MD,medium and coarse particle sizes resulted in higher(P < 0.05) BW, ADG and ADFI than fine particle size during the whole experiment. In CPD, particle size had no significant effect on growth performance, as indicated by a feed form × particle size interaction(P < 0.05). At 41 days of age, ten birds per treatment were randomly selected and killed for slaughter yields and digestive tract characteristics determination.It was shown that particle size and feed form alone had no significant effect on slaughter yields, so changes was the feed form × particle size interaction. The relative empty weight of the gizzard was greater(P < 0.01) and the relative length of the ileum was longer(P < 0.05) in birds fed MD than in those fed CPD. Overall, CPD improved growth performance during the entire period of the study with effects being less evident during the finisher phase than during the starter and grower phases, and the effect of feed particle size varied depending on feed form.
文摘Modern industrial technologies call for the development of novel materials with improved surface properties, lower costs and environmentally suitable processes. Plasma spray coating process has become a subject of intense research which attempts to create functional layers on the surface is obviously the most economical way to provide high per- formance to machinery and industrial equipments. The present work aims at developing and studying the industrial wastes (Flay-ash, Quartz and illmenite composite mixture) as the coating material, which is to be deposited on Mild Steel and Copper substrates. To study and evaluate Coating deposition efficiency, artificial neural network analysis (ANN) technique is used. By this quality control technique, it is sufficient to describe approximation complex of in- ter-relationships of operating parameters in atmospheric plasma spray process. ANN technique helps in saving time and resources for experimental trials. The aim of this work is to outline a procedure for selecting an appropriate input vec- tors in ANN coating efficiency models, based on statistical pre-processing of the experimental data set. This methodology can provide deep understanding of various co-relationships across multiple scales of length and time, which could be essential for improvement of product and process performance. The deposition efficiency of coatings has a strong dependence on input power level, particle size of the feed material, powder feed rate and torch to substrate distance. ANN experimental results indicate that the projection network has good generalization capability to optimize the deposition efficiency, when an appropriate size of training set and network is utilized.
