Hydraulic asphalt concrete(HAC)has been increasingly employed as an appropriate impervious structure in hydraulic and hydropower engineering.However,asphalt mortar,usually seen as the matrix of HAC composite,is partic...Hydraulic asphalt concrete(HAC)has been increasingly employed as an appropriate impervious structure in hydraulic and hydropower engineering.However,asphalt mortar,usually seen as the matrix of HAC composite,is particularly prone to damage under combined stress and seepage interactions,and the mesoscale investigations on the damage-seepage coupling behavior of HAC under complex stress states remain limited.This research develops a numerical three-dimensional mesoscale model composed of asphalt mortar and polyhedral aggregate to investigate the stress-damage-seepage coupling behavior in HAC.In this model,asphalt mortar yields the viscoelastic continuum damage law and aggregate obeys the Mazars’elastic-brittle damage law;simultaneously,the effective permeability coefficient of asphalt mortar is assumed to follow an exponential function of damage.The predicted deviatoric stress-strain and hydraulic gradient-seepage curves both are in good agreement with the reported experimental results,which shows the proposed model is valid and reasonable.The simulated results indicate that the damaged asphalt mortar can induce localized areas of high permeability,which in turn affects the overall impervious performance of HAC.展开更多
Although traditional gamma-gamma density(GGD)logging technology is widely utilized,its potential environmental risks have prompted the development of more environmentally friendly neutron-gamma density(NGD)logging tec...Although traditional gamma-gamma density(GGD)logging technology is widely utilized,its potential environmental risks have prompted the development of more environmentally friendly neutron-gamma density(NGD)logging technology.However,NGD measurements are influenced by both neutron and gamma radiations.In the logging environment,variations in the formation composition indicate different elemental compositions,which affect the neutron-gamma reaction cross-sections and gamma generation.Compared to traditional gamma sources such as Cs-137,these changes significantly affect the generation and transport of neutron-induced inelastic gamma rays and hinder accurate measurements.To address this,a novel method is proposed that incorporates the mass attenuation coefficient function to account for the effects of various lithologies and pore contents on gamma-ray attenuation,thereby achieving more accurate density measurements by clarifying the transport processes of inelastic gamma rays with varying energies and spatial distributions in varied logging environments.The proposed method avoids the complex correction of neutron transport and is verified through Monte Carlo simulations for its applicability across various lithologies and pore contents,demonstrating absolute density errors that are less than 0.02 g/cm^(3)in clean formations and indicating good accuracy.This study clarifies the NGD mechanism and provides theoretical guidance for the application of NGD logging methods.Further studies will be conducted on extreme environmental conditions and tool calibration.展开更多
目的研究昆明地区RhD初筛阴性献血者RHD基因的多态性及其分子机制,为建立区域性献血者RHD基因数据库提供数据支持。方法选择昆明地区2023年11月-2024年8月初筛RhD阴性标本218例,采用间接抗球蛋白试验法(IAT)进行RhD阴性确认,采用盐水试...目的研究昆明地区RhD初筛阴性献血者RHD基因的多态性及其分子机制,为建立区域性献血者RHD基因数据库提供数据支持。方法选择昆明地区2023年11月-2024年8月初筛RhD阴性标本218例,采用间接抗球蛋白试验法(IAT)进行RhD阴性确认,采用盐水试管法进行RhCE表型鉴定。提取全血基因组DNA,采用PCR-SSP法/SSP荧光PCR染料法进行RHD基因分型,对无法确定基因型的标本进行RHD基因1~10外显子Sanger测序分析。结果检出RhD真阴性表型179例(82.11%),其中RHD*01N.01(RHD全缺失)型154例(86.03%),表型以ccee为主(87.01%);携带非功能性RHD等位基因25例(13.97%),包括RHD*01N.0320例、RHD*01N.163例、RHD*01N.051例、RHD*01N.591例,表型以Ccee为主(64%)。检出D变异型39例(15.89%),其中RHD*DEL1(c.1227G>A)型34例,表型均为C抗原阳性(Ccee 27例,CCee 7例);弱D/部分D型4例,包括RHD*DVI.32例、RHD*weak D type 711例、RHD*weak D type1081例;另检出1例RHD*01/RHD*01N.01,基因型与血清学表型结果不一致。RHD*01N.01女性献血者不规则抗体(主要为抗-D)阳性率9.84%。结论昆明地区RhD初筛阴性献血者RHD基因多态性显著,RhD真阴性比例高于国内部分地区,D变异型以“亚洲型”DEL为主,比例低于国内部分地区。研究结果为本地区RhD阴性和D变异型个体精准输血提供了理论和数据支持。展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2022YFC3005603-01)the Natural Science Foundation Science of Anhui Province(Grant No.2308085US02).
文摘Hydraulic asphalt concrete(HAC)has been increasingly employed as an appropriate impervious structure in hydraulic and hydropower engineering.However,asphalt mortar,usually seen as the matrix of HAC composite,is particularly prone to damage under combined stress and seepage interactions,and the mesoscale investigations on the damage-seepage coupling behavior of HAC under complex stress states remain limited.This research develops a numerical three-dimensional mesoscale model composed of asphalt mortar and polyhedral aggregate to investigate the stress-damage-seepage coupling behavior in HAC.In this model,asphalt mortar yields the viscoelastic continuum damage law and aggregate obeys the Mazars’elastic-brittle damage law;simultaneously,the effective permeability coefficient of asphalt mortar is assumed to follow an exponential function of damage.The predicted deviatoric stress-strain and hydraulic gradient-seepage curves both are in good agreement with the reported experimental results,which shows the proposed model is valid and reasonable.The simulated results indicate that the damaged asphalt mortar can induce localized areas of high permeability,which in turn affects the overall impervious performance of HAC.
基金supported by the National Natural Science Foundation of China(U23B20151 and 52171253).
文摘Although traditional gamma-gamma density(GGD)logging technology is widely utilized,its potential environmental risks have prompted the development of more environmentally friendly neutron-gamma density(NGD)logging technology.However,NGD measurements are influenced by both neutron and gamma radiations.In the logging environment,variations in the formation composition indicate different elemental compositions,which affect the neutron-gamma reaction cross-sections and gamma generation.Compared to traditional gamma sources such as Cs-137,these changes significantly affect the generation and transport of neutron-induced inelastic gamma rays and hinder accurate measurements.To address this,a novel method is proposed that incorporates the mass attenuation coefficient function to account for the effects of various lithologies and pore contents on gamma-ray attenuation,thereby achieving more accurate density measurements by clarifying the transport processes of inelastic gamma rays with varying energies and spatial distributions in varied logging environments.The proposed method avoids the complex correction of neutron transport and is verified through Monte Carlo simulations for its applicability across various lithologies and pore contents,demonstrating absolute density errors that are less than 0.02 g/cm^(3)in clean formations and indicating good accuracy.This study clarifies the NGD mechanism and provides theoretical guidance for the application of NGD logging methods.Further studies will be conducted on extreme environmental conditions and tool calibration.
文摘目的研究昆明地区RhD初筛阴性献血者RHD基因的多态性及其分子机制,为建立区域性献血者RHD基因数据库提供数据支持。方法选择昆明地区2023年11月-2024年8月初筛RhD阴性标本218例,采用间接抗球蛋白试验法(IAT)进行RhD阴性确认,采用盐水试管法进行RhCE表型鉴定。提取全血基因组DNA,采用PCR-SSP法/SSP荧光PCR染料法进行RHD基因分型,对无法确定基因型的标本进行RHD基因1~10外显子Sanger测序分析。结果检出RhD真阴性表型179例(82.11%),其中RHD*01N.01(RHD全缺失)型154例(86.03%),表型以ccee为主(87.01%);携带非功能性RHD等位基因25例(13.97%),包括RHD*01N.0320例、RHD*01N.163例、RHD*01N.051例、RHD*01N.591例,表型以Ccee为主(64%)。检出D变异型39例(15.89%),其中RHD*DEL1(c.1227G>A)型34例,表型均为C抗原阳性(Ccee 27例,CCee 7例);弱D/部分D型4例,包括RHD*DVI.32例、RHD*weak D type 711例、RHD*weak D type1081例;另检出1例RHD*01/RHD*01N.01,基因型与血清学表型结果不一致。RHD*01N.01女性献血者不规则抗体(主要为抗-D)阳性率9.84%。结论昆明地区RhD初筛阴性献血者RHD基因多态性显著,RhD真阴性比例高于国内部分地区,D变异型以“亚洲型”DEL为主,比例低于国内部分地区。研究结果为本地区RhD阴性和D变异型个体精准输血提供了理论和数据支持。
