为提高风光等新能源利用效率,促进新型能源的多元化利用,构建绿色清洁、安全可控的能源系统,助力“双碳”目标的实现,以电氢综合能源系统(Electric hydrogen integrated energy system,EHIES)为研究对象,构建了考虑氢能系统热回收利用...为提高风光等新能源利用效率,促进新型能源的多元化利用,构建绿色清洁、安全可控的能源系统,助力“双碳”目标的实现,以电氢综合能源系统(Electric hydrogen integrated energy system,EHIES)为研究对象,构建了考虑氢能系统热回收利用的综合运行模型。该模型的氢能系统包含电解槽、储氢罐、甲烷化设备及氢燃料电池等,针对新能源出力的不确定性,建立了多面体不确定性数据集模型及EHIES两阶段鲁棒运行优化模型,并采用列和约束算法进行求解和仿真分析。模拟结果表明,氢能系统余热回收可有效降低约6.7%的运行成本,所提模型能有效提升系统鲁棒性和能源利用效率,可为氢能源的多元化利用提供一定的参考。展开更多
Background:Oleic acid is an abundant free fatty acid present in livestock that are in a negative energy-balance state,and it may have detrimental effects on female reproduction and fertility.Oleic acid induces lipid a...Background:Oleic acid is an abundant free fatty acid present in livestock that are in a negative energy-balance state,and it may have detrimental effects on female reproduction and fertility.Oleic acid induces lipid accumulation in bovine granulosa cells,which leads to a foam cell-like morphology and reduced steroidogenesis.However,why oleic acid increases lipid accumulation but decreases steroidogenesis remains unclear.This study focused on oleic acid’s effects on lipid type and steroidogenesis.Results:Oleic acid increased the lipid accumulation in a concentration-dependent manner and mainly increased the triglyceride level and decreased the cholesterol ester level.Oleic acid also led to a decline in estradiol and progesterone production in porcine granulosa cells in vitro.In addition,oleic acid up-regulated the expression of CD36 and diacylglycerol acyltransferase 2,but down-regulated the expression of 3-hydroxy-3-methylglutarylcoenzyme A reductase,scavenger receptor class B member 1 and acetyl-Coenzyme A acetyltransferase 2,as well as steroidogenesis-related genes,including cytochrome P450 family 11 subfamily A member 1,cytochrome P450family 19 subfamily A member 1 and 3 as well as steroidogenic acute regulatory protein at the mRNA and protein levels.An oleic acid-rich diet also enhanced the triglyceride levels and reduced the cholesterol levels in ovarian tissues of female mice,which resulted in lower estradiol levels than in control-fed mice.Compared with the control,decreases in estrus days and the numbers of antral follicles and corpora lutea,as well as an increase in the numbers of the atretic follicles,were found in the oleic acid-fed female mice.Conclusions:Oleic acid changed the lipid type stored in lipid droplets of ovarian granulosa cells,and led to a decrease in steroidogenesis.These results improve our understanding of fertility decline in livestock that are in a negative energy-balance state.展开更多
A new industrial production method of 2, 3-butanediol is discussed in this paper. C2-4 bio-polyol is prepared by combining biological fermentation and chemical cleavage, with corn starch as raw material. In this indus...A new industrial production method of 2, 3-butanediol is discussed in this paper. C2-4 bio-polyol is prepared by combining biological fermentation and chemical cleavage, with corn starch as raw material. In this industrial method, high purity 2,3-butanediol can be obtained after distillation and purification. Low production cost of this method provides an effective support for 2, 3-butanediol large-scaled application.展开更多
Modeling a system in engineering applications is a time-consuming and labor-intensive task,as system parameters may change with temperature,component aging,etc.In this paper,a novel data-driven model-free optimal cont...Modeling a system in engineering applications is a time-consuming and labor-intensive task,as system parameters may change with temperature,component aging,etc.In this paper,a novel data-driven model-free optimal controller based on deep deterministic policy gradient(DDPG)is proposed to address the problem of continuous-time leader-following multi-agent consensus.To deal with the problem of the dimensional explosion of state space and action space,two different types of neural nets are utilized to fit them instead of the time-consuming state iteration process.With minimal energy consumption,the proposed controller achieves consensus only based on the consensus error and does not require any initial admissible policies.Besides,the controller is self-learning,which means it can achieve optimal control by learning in real time as the system parameters change.Finally,the proofs of convergence and stability,as well as some simulation experiments,are provided to verify the algorithm’s effectiveness.展开更多
文摘为提高风光等新能源利用效率,促进新型能源的多元化利用,构建绿色清洁、安全可控的能源系统,助力“双碳”目标的实现,以电氢综合能源系统(Electric hydrogen integrated energy system,EHIES)为研究对象,构建了考虑氢能系统热回收利用的综合运行模型。该模型的氢能系统包含电解槽、储氢罐、甲烷化设备及氢燃料电池等,针对新能源出力的不确定性,建立了多面体不确定性数据集模型及EHIES两阶段鲁棒运行优化模型,并采用列和约束算法进行求解和仿真分析。模拟结果表明,氢能系统余热回收可有效降低约6.7%的运行成本,所提模型能有效提升系统鲁棒性和能源利用效率,可为氢能源的多元化利用提供一定的参考。
基金supported by grants from the National Natural Science Foundation(No.31802047)the National Science and Technology Major Project of China(No.2016ZX08006003)。
文摘Background:Oleic acid is an abundant free fatty acid present in livestock that are in a negative energy-balance state,and it may have detrimental effects on female reproduction and fertility.Oleic acid induces lipid accumulation in bovine granulosa cells,which leads to a foam cell-like morphology and reduced steroidogenesis.However,why oleic acid increases lipid accumulation but decreases steroidogenesis remains unclear.This study focused on oleic acid’s effects on lipid type and steroidogenesis.Results:Oleic acid increased the lipid accumulation in a concentration-dependent manner and mainly increased the triglyceride level and decreased the cholesterol ester level.Oleic acid also led to a decline in estradiol and progesterone production in porcine granulosa cells in vitro.In addition,oleic acid up-regulated the expression of CD36 and diacylglycerol acyltransferase 2,but down-regulated the expression of 3-hydroxy-3-methylglutarylcoenzyme A reductase,scavenger receptor class B member 1 and acetyl-Coenzyme A acetyltransferase 2,as well as steroidogenesis-related genes,including cytochrome P450 family 11 subfamily A member 1,cytochrome P450family 19 subfamily A member 1 and 3 as well as steroidogenic acute regulatory protein at the mRNA and protein levels.An oleic acid-rich diet also enhanced the triglyceride levels and reduced the cholesterol levels in ovarian tissues of female mice,which resulted in lower estradiol levels than in control-fed mice.Compared with the control,decreases in estrus days and the numbers of antral follicles and corpora lutea,as well as an increase in the numbers of the atretic follicles,were found in the oleic acid-fed female mice.Conclusions:Oleic acid changed the lipid type stored in lipid droplets of ovarian granulosa cells,and led to a decrease in steroidogenesis.These results improve our understanding of fertility decline in livestock that are in a negative energy-balance state.
文摘A new industrial production method of 2, 3-butanediol is discussed in this paper. C2-4 bio-polyol is prepared by combining biological fermentation and chemical cleavage, with corn starch as raw material. In this industrial method, high purity 2,3-butanediol can be obtained after distillation and purification. Low production cost of this method provides an effective support for 2, 3-butanediol large-scaled application.
基金supported by the Tianjin Natural Science Foundation of China(Grant No.20JCYBJC01060)the National Natural Science Foundation of China(Grant Nos.62103203 and 61973175)the Fundamental Research Funds for the Central Universities,Nankai University(Grant No.63221218)。
文摘Modeling a system in engineering applications is a time-consuming and labor-intensive task,as system parameters may change with temperature,component aging,etc.In this paper,a novel data-driven model-free optimal controller based on deep deterministic policy gradient(DDPG)is proposed to address the problem of continuous-time leader-following multi-agent consensus.To deal with the problem of the dimensional explosion of state space and action space,two different types of neural nets are utilized to fit them instead of the time-consuming state iteration process.With minimal energy consumption,the proposed controller achieves consensus only based on the consensus error and does not require any initial admissible policies.Besides,the controller is self-learning,which means it can achieve optimal control by learning in real time as the system parameters change.Finally,the proofs of convergence and stability,as well as some simulation experiments,are provided to verify the algorithm’s effectiveness.
