The receiver is an important element in solar energy plants.The principal receiver’s tubes in power plants are devised to work under extremely severe conditions,including excessive heat fluxes.Half of the tube’s cir...The receiver is an important element in solar energy plants.The principal receiver’s tubes in power plants are devised to work under extremely severe conditions,including excessive heat fluxes.Half of the tube’s circumference is heated whilst the other half is insulated.This study aims to improve the heat transfer process and reinforce the tubes’structure by designing a new receiver;by including longitudinal fins of triangular,circular and square shapes.The research is conducted experimentally using Reynolds numbers ranging from 28,000 to 78,000.Triangular fins have demonstrated the best improvement for heat transfer.For Reynolds number value near 43,000 Nusselt number(Nu)is higher by 3.5%and 7.5%,sequentially,compared to circular and square tube fins,but varies up to 6.5%near Re=61000.The lowest friction factor is seen in a triangular fin receiver;where it deviates from circular fins by 4.6%,and square fin tubes by 3.2%.Adding fins makes the temperature decrease gradually,and in the case of no fins,the temperature gradient between the hot tube and water drops sharply in the planed tube by 7%.展开更多
DNA hypermethylation is an epigenetic modification that plays a critical role in the oncogenesis of myelodysplastic syndromes(MDS).Aberrant DNA methylation represses the transcription of promotors of tumor suppressor ...DNA hypermethylation is an epigenetic modification that plays a critical role in the oncogenesis of myelodysplastic syndromes(MDS).Aberrant DNA methylation represses the transcription of promotors of tumor suppressor genes,inducing gene silencing.Realgar(α-As_(4)S_(4))is a traditional medicine used for the treatment of various diseases in the ancient time.Realgar was reported to have efficacy for acute promyelocytic leukemia(APL).It has been demonstrated that realgar could efficiently reduce DNA hypermethylation of MDS.This review discusses the mechanisms of realgar on inhibiting DNA hypermethylation of MDS,as well as the species and metabolisms of arsenic in vivo.展开更多
文摘The receiver is an important element in solar energy plants.The principal receiver’s tubes in power plants are devised to work under extremely severe conditions,including excessive heat fluxes.Half of the tube’s circumference is heated whilst the other half is insulated.This study aims to improve the heat transfer process and reinforce the tubes’structure by designing a new receiver;by including longitudinal fins of triangular,circular and square shapes.The research is conducted experimentally using Reynolds numbers ranging from 28,000 to 78,000.Triangular fins have demonstrated the best improvement for heat transfer.For Reynolds number value near 43,000 Nusselt number(Nu)is higher by 3.5%and 7.5%,sequentially,compared to circular and square tube fins,but varies up to 6.5%near Re=61000.The lowest friction factor is seen in a triangular fin receiver;where it deviates from circular fins by 4.6%,and square fin tubes by 3.2%.Adding fins makes the temperature decrease gradually,and in the case of no fins,the temperature gradient between the hot tube and water drops sharply in the planed tube by 7%.
文摘DNA hypermethylation is an epigenetic modification that plays a critical role in the oncogenesis of myelodysplastic syndromes(MDS).Aberrant DNA methylation represses the transcription of promotors of tumor suppressor genes,inducing gene silencing.Realgar(α-As_(4)S_(4))is a traditional medicine used for the treatment of various diseases in the ancient time.Realgar was reported to have efficacy for acute promyelocytic leukemia(APL).It has been demonstrated that realgar could efficiently reduce DNA hypermethylation of MDS.This review discusses the mechanisms of realgar on inhibiting DNA hypermethylation of MDS,as well as the species and metabolisms of arsenic in vivo.
