Based on the“three box”exergy analysis model,a black box-gray box hierarchical exergy analysis and evaluation method is put forward in this paper,which is applied to evaluate the power generation technology of diffe...Based on the“three box”exergy analysis model,a black box-gray box hierarchical exergy analysis and evaluation method is put forward in this paper,which is applied to evaluate the power generation technology of differential pressure produced by natural gas expansion.By using the exergy analysis theory,the black box-gray box hierarchical exergy analysis models of three differential pressure power generation technologies are established respectively.Firstly,the“black box”analysis models of main energy consuming equipment are established,and then the“gray box”analysis model of the total system is established.Based on the calculation results of exergy analysis indexes,the weak energy consumption equipment in the whole power generation process is accurately located.Taking a gas field in southwest China as an example,the comprehensive energy consumption evaluation of the three power generation technologies is carried out,and the technology with the best energy consumption condition among the three technologies is determined.Finally,the rationalization improvement measures are put forward from improving the air tightness,replacing the deflector and reducing the flow loss.展开更多
The singularly perturbed nonlinear boundary value problems are considered.Using the stretched variable and the method of boundary layer correction,the formal asymptotic expansion of solution is obtained.And then the u...The singularly perturbed nonlinear boundary value problems are considered.Using the stretched variable and the method of boundary layer correction,the formal asymptotic expansion of solution is obtained.And then the uniform validity of solution is proved by using the differential inequalities.展开更多
In this paper,a class of singular perturbation of nonlocal boundary value problems for elliptic partial differential equations of higher order is considered by using the differential inequalities.The uniformly valid a...In this paper,a class of singular perturbation of nonlocal boundary value problems for elliptic partial differential equations of higher order is considered by using the differential inequalities.The uniformly valid asymptotic expansion of solution is obtained.展开更多
Studying the regulatory mechanisms that drive nitrogen-use efficiency(NUE)in crops is important for sustainable agriculture and environmental protection.In this study,we generated a high-quality genome assembly for th...Studying the regulatory mechanisms that drive nitrogen-use efficiency(NUE)in crops is important for sustainable agriculture and environmental protection.In this study,we generated a high-quality genome assembly for the high-NUE wheat cultivar Kenong 9204 and systematically analyzed genes related to nitrogen uptake and metabolism.By comparative analyses,we found that the high-affinity nitrate transporter gene family had expanded in Triticeae.Further studies showed that subsequent functional differentiation endowed the expanded family members with saline inducibility,providing a genetic basis for improving the adaptability of wheat to nitrogen deficiency in various habitats.To explore the genetic and molecular mechanisms of high NUE,we compared genomic and transcriptomic data from the high-NUE cultivar Kenong 9204(KN9204)and the low-NUE cultivar Jing 411 and quantified their nitrogen accumulation under high-and low-nitrogen conditions.Compared with Jing 411,KN9204 absorbed significantly more nitrogen at the reproductive stage after shooting and accumulated it in the shoots and seeds.Transcriptome data analysis revealed that nitrogen deficiency clearly suppressed the expression of genes related to cell division in the young spike of Jing 411,whereas this suppression of gene expression was much lower in KN9204.In addition,KN9204 maintained relatively high expression of NPF genes for a longer time than Jing 411 during seed maturity.Physiological and transcriptome data revealed that KN9204 was more tolerant of nitrogen deficiency than Jing 411,especially at the reproductive stage.The high NUE of KN9204 is an integrated effect controlled at different levels.Taken together,our data provide new insights into the molecular mechanisms of NUE and important gene resources for improving wheat cultivars with a higher NUE trait.展开更多
基金financially supported by the National Natural Science Foundation of China(52074089 and 51534004)Natural Science Foundation of Heilongjiang Province of China(LH2019E019)。
文摘Based on the“three box”exergy analysis model,a black box-gray box hierarchical exergy analysis and evaluation method is put forward in this paper,which is applied to evaluate the power generation technology of differential pressure produced by natural gas expansion.By using the exergy analysis theory,the black box-gray box hierarchical exergy analysis models of three differential pressure power generation technologies are established respectively.Firstly,the“black box”analysis models of main energy consuming equipment are established,and then the“gray box”analysis model of the total system is established.Based on the calculation results of exergy analysis indexes,the weak energy consumption equipment in the whole power generation process is accurately located.Taking a gas field in southwest China as an example,the comprehensive energy consumption evaluation of the three power generation technologies is carried out,and the technology with the best energy consumption condition among the three technologies is determined.Finally,the rationalization improvement measures are put forward from improving the air tightness,replacing the deflector and reducing the flow loss.
文摘The singularly perturbed nonlinear boundary value problems are considered.Using the stretched variable and the method of boundary layer correction,the formal asymptotic expansion of solution is obtained.And then the uniform validity of solution is proved by using the differential inequalities.
文摘In this paper,a class of singular perturbation of nonlocal boundary value problems for elliptic partial differential equations of higher order is considered by using the differential inequalities.The uniformly valid asymptotic expansion of solution is obtained.
基金supported by the National Natural Science Foundation of China(grant nos.31921005 and 31991211)the Strategic Priority Research Program of the Chinese Academy of Sciences(grant nos.XDA24010104,XDA24010204,and XDA24030102)+1 种基金the Special Information Program of the Chinese Academy of Sciences(grant no.XXH13506-408)the China Agricultural Research System(grant no.CARS-03).
文摘Studying the regulatory mechanisms that drive nitrogen-use efficiency(NUE)in crops is important for sustainable agriculture and environmental protection.In this study,we generated a high-quality genome assembly for the high-NUE wheat cultivar Kenong 9204 and systematically analyzed genes related to nitrogen uptake and metabolism.By comparative analyses,we found that the high-affinity nitrate transporter gene family had expanded in Triticeae.Further studies showed that subsequent functional differentiation endowed the expanded family members with saline inducibility,providing a genetic basis for improving the adaptability of wheat to nitrogen deficiency in various habitats.To explore the genetic and molecular mechanisms of high NUE,we compared genomic and transcriptomic data from the high-NUE cultivar Kenong 9204(KN9204)and the low-NUE cultivar Jing 411 and quantified their nitrogen accumulation under high-and low-nitrogen conditions.Compared with Jing 411,KN9204 absorbed significantly more nitrogen at the reproductive stage after shooting and accumulated it in the shoots and seeds.Transcriptome data analysis revealed that nitrogen deficiency clearly suppressed the expression of genes related to cell division in the young spike of Jing 411,whereas this suppression of gene expression was much lower in KN9204.In addition,KN9204 maintained relatively high expression of NPF genes for a longer time than Jing 411 during seed maturity.Physiological and transcriptome data revealed that KN9204 was more tolerant of nitrogen deficiency than Jing 411,especially at the reproductive stage.The high NUE of KN9204 is an integrated effect controlled at different levels.Taken together,our data provide new insights into the molecular mechanisms of NUE and important gene resources for improving wheat cultivars with a higher NUE trait.