Two 3×3 factorial design trials with 1 080 of Yorkshire×Landrace×Duroc barrows were conducted to investigate the effects of dietary net energy （NE） density and standardized ileal digestible （SID） ly...Two 3×3 factorial design trials with 1 080 of Yorkshire×Landrace×Duroc barrows were conducted to investigate the effects of dietary net energy （NE） density and standardized ileal digestible （SID） lysine：NE ratio on the performance of growing- finishing pigs and carcass characteristic of finishing pigs fed low crude protein （CP） supplemented with crystalline amino acids （CAA） diets. Low CP corn-soybean meal basal diets （14% for Exp. 1 and 11% for Exp. 2） supplemented with crystalline lysine, methionine, threonine, and tryptophan were formulated. Nine treatments with increasing NE density and SID lysine：NE ratio were used in each trial （Exp. 1： 9.66, 9.87, and 10.08 MJ kg-1 NE, 0.89, 0.96, and 1.03 g MJ-1 SID lysine： NE; Exp. 2： 9.83, 10.04, and 10.25 MJ kg-1 NE, 0.69, 0.76, and 0.83 g MJ-1 SID lysine：NE）. In Exp. 1, we observed that the average daily gain （ADG） for barrows that received the diet containing 9.87 MJ kg-1 NE was significantly higher than that of barrows fed a 9.66 MJ kg-1 NE diet （P0.05）, but no difference was observed when compared with barrows that received a diet containing 10.08 MJ kg-1 NE （P0.05）. The ADG was affected both linearly （P0.05） and quadratically （P0.05） as the SID lysine：NE ratio increased. The NE density or SID lysine：NE ratio and their interaction had no effect on the average daily feed intake （ADFI） and serum urea nitrogen （SUN） （P0.05）. The feed to gain ratio （F：G） decreased （linearly, P0.05; quadratically, P0.05） as the NE density or SID lysine：NE ratio increased, but no interaction of NE density and SID lysine： NE ratio on the F：G. In Exp. 2, the dietary NE density both linearly （P0.05） and quadratically （P0.05） affected the ADG and F：G. Barrows that received a diet containing 10.04 MJ kg-1 NE had a greater ADG （P0.05） than barrows that received a 9.83 MJ kg-1 diet, but there was no difference （P0.05） as compared with barrows that received a diet containing 10.25 MJ kg-1 NE. F：G was significantly higher （P0.05） for barrows that received a 9.83 MJ kg-1 diet when compared with barrows that received the other two diets. The ADG was significantly decreased （P0.05） for pigs that received a diet containing 0.69 g MJ-1 SID lysine：NE ratio when compared with pigs fed a diet containing 0.76 or 0.83 g MJ-1 SID lysine：NE ratio. The NE density or SID lysine：NE ratio and their interaction had no effect on the average daily feed intake, SUN, and carcass characteristic for finishing barrows （P0.05）. The overall results of the two experiments indicated that barrows that received the diet with the dietary CP level reduced 4 percentage units compared the NRC （1998） recommendations. Maximized the best performance with NE density and SID lysine：NE ratio were 9.87 MJ kg-1, 1.03 g MJ-1 NE for 20-50 kg pigs, and 10.04 MJ kg-1, 0.76 g MJ-1 NE for 60-100 kg pigs, respectively.展开更多
Performance of automotive engine oils at low temperature has been extensively investigated in the last 50 years.The resulting understanding of engine oil rheology has been used to devise bench tests that predict their...Performance of automotive engine oils at low temperature has been extensively investigated in the last 50 years.The resulting understanding of engine oil rheology has been used to devise bench tests that predict their per- formance under cold starting conditions.Cold starting the engine has been essentially overcome for passenger car en- gines with fuel injection but pumpability of the engine oil has grown more demanding.Two tests(MRV TP1 and the Scanning Brookfield Technique with Gelation Index measurement)have become the measures of quality in pumpabili- ty response at low temperatures.As such they have become ASTM Methods and are included in a number of interna- tional specifications such as SAE J300 and ILSAC/API GF-1,2,3,and 4 accompanied by appropriate limits. For a number of years,the Institute of Materials(IOM) has generated a database for Asia-Pacific engine oils for IOM Subscribers.This database can be used to assess and compare the performance of Chinese engine oils at low temperature to one another and to the larger world of engine oils also covered by the IOM database.This IOM survey of Asia-Pacific provides a complete 36-test analysis of 300 passenger car engine oils from the region including a wide range of chemical analysis,rheological measurements and performance assessments.In this paper we concen- trate on the low temperature analysis of the rheology of samples collected in China since 2000. The important factors affecting formulation of engine oils in China today are: 1.The recent inclusion of the MRV TP-1 and Scanning Brookfield Gelation Index requirements in China's National Standards for engine oil quality; 2.The availability of higher quality oils; 3.The higher treat rate of additives will require increased attention from the formulators in the selection of VI Improvers and Pour Point Depressants(PPDs). In the latter case,new PPDs are likely to be required to provide formulators with robust and economical solu- tions to face these new challenges.Some examples will be given to illustrate the important effects of type and concen- tration of PPD on engine oil pumpability.展开更多
基金supported by the National Key Tech-nology R&D Program of China (2006BAD12B02)
文摘Two 3×3 factorial design trials with 1 080 of Yorkshire×Landrace×Duroc barrows were conducted to investigate the effects of dietary net energy （NE） density and standardized ileal digestible （SID） lysine：NE ratio on the performance of growing- finishing pigs and carcass characteristic of finishing pigs fed low crude protein （CP） supplemented with crystalline amino acids （CAA） diets. Low CP corn-soybean meal basal diets （14% for Exp. 1 and 11% for Exp. 2） supplemented with crystalline lysine, methionine, threonine, and tryptophan were formulated. Nine treatments with increasing NE density and SID lysine：NE ratio were used in each trial （Exp. 1： 9.66, 9.87, and 10.08 MJ kg-1 NE, 0.89, 0.96, and 1.03 g MJ-1 SID lysine： NE; Exp. 2： 9.83, 10.04, and 10.25 MJ kg-1 NE, 0.69, 0.76, and 0.83 g MJ-1 SID lysine：NE）. In Exp. 1, we observed that the average daily gain （ADG） for barrows that received the diet containing 9.87 MJ kg-1 NE was significantly higher than that of barrows fed a 9.66 MJ kg-1 NE diet （P0.05）, but no difference was observed when compared with barrows that received a diet containing 10.08 MJ kg-1 NE （P0.05）. The ADG was affected both linearly （P0.05） and quadratically （P0.05） as the SID lysine：NE ratio increased. The NE density or SID lysine：NE ratio and their interaction had no effect on the average daily feed intake （ADFI） and serum urea nitrogen （SUN） （P0.05）. The feed to gain ratio （F：G） decreased （linearly, P0.05; quadratically, P0.05） as the NE density or SID lysine：NE ratio increased, but no interaction of NE density and SID lysine： NE ratio on the F：G. In Exp. 2, the dietary NE density both linearly （P0.05） and quadratically （P0.05） affected the ADG and F：G. Barrows that received a diet containing 10.04 MJ kg-1 NE had a greater ADG （P0.05） than barrows that received a 9.83 MJ kg-1 diet, but there was no difference （P0.05） as compared with barrows that received a diet containing 10.25 MJ kg-1 NE. F：G was significantly higher （P0.05） for barrows that received a 9.83 MJ kg-1 diet when compared with barrows that received the other two diets. The ADG was significantly decreased （P0.05） for pigs that received a diet containing 0.69 g MJ-1 SID lysine：NE ratio when compared with pigs fed a diet containing 0.76 or 0.83 g MJ-1 SID lysine：NE ratio. The NE density or SID lysine：NE ratio and their interaction had no effect on the average daily feed intake, SUN, and carcass characteristic for finishing barrows （P0.05）. The overall results of the two experiments indicated that barrows that received the diet with the dietary CP level reduced 4 percentage units compared the NRC （1998） recommendations. Maximized the best performance with NE density and SID lysine：NE ratio were 9.87 MJ kg-1, 1.03 g MJ-1 NE for 20-50 kg pigs, and 10.04 MJ kg-1, 0.76 g MJ-1 NE for 60-100 kg pigs, respectively.
文摘Performance of automotive engine oils at low temperature has been extensively investigated in the last 50 years.The resulting understanding of engine oil rheology has been used to devise bench tests that predict their per- formance under cold starting conditions.Cold starting the engine has been essentially overcome for passenger car en- gines with fuel injection but pumpability of the engine oil has grown more demanding.Two tests(MRV TP1 and the Scanning Brookfield Technique with Gelation Index measurement)have become the measures of quality in pumpabili- ty response at low temperatures.As such they have become ASTM Methods and are included in a number of interna- tional specifications such as SAE J300 and ILSAC/API GF-1,2,3,and 4 accompanied by appropriate limits. For a number of years,the Institute of Materials(IOM) has generated a database for Asia-Pacific engine oils for IOM Subscribers.This database can be used to assess and compare the performance of Chinese engine oils at low temperature to one another and to the larger world of engine oils also covered by the IOM database.This IOM survey of Asia-Pacific provides a complete 36-test analysis of 300 passenger car engine oils from the region including a wide range of chemical analysis,rheological measurements and performance assessments.In this paper we concen- trate on the low temperature analysis of the rheology of samples collected in China since 2000. The important factors affecting formulation of engine oils in China today are: 1.The recent inclusion of the MRV TP-1 and Scanning Brookfield Gelation Index requirements in China's National Standards for engine oil quality; 2.The availability of higher quality oils; 3.The higher treat rate of additives will require increased attention from the formulators in the selection of VI Improvers and Pour Point Depressants(PPDs). In the latter case,new PPDs are likely to be required to provide formulators with robust and economical solu- tions to face these new challenges.Some examples will be given to illustrate the important effects of type and concen- tration of PPD on engine oil pumpability.
