The through-diffusion and membrane behavior testing procedure using a closed-system apparatus has been widely used for concurrent measurement of diffusion and membrane efficiency coefficients of low-permeability clay-...The through-diffusion and membrane behavior testing procedure using a closed-system apparatus has been widely used for concurrent measurement of diffusion and membrane efficiency coefficients of low-permeability clay-based barrier materials.However,the common assumption of perfectly flushing conditions at the specimen boundaries could induce errors in analyses of the diffusion coefficients and membrane efficiencies.In this study,an innovative pseudo three-dimensional(3D)analytical method was proposed to evaluate solute distribution along the boundary surfaces of the soil-porous disks system,considering the non-perfectly flushing conditions.The results were consistent with numerical models under two scenarios considering different inflow/outflow positions.The proposed model has been demonstrated to be an accurate and reliable method to estimate solute distributions along the bound-aries.The calculated membrane efficiency coefficient and diffusion coefficient based on the proposed analytical method are more accurate,resulting in up to 50%less relative error than the traditional approach that adopts the arithmetic mean value of the influent and effluent concentrations.The retar-dation factor of the clay specimen also can be calculated with a revised cumulative mass approach.Finally,the simulated transient solute transport matched with experimental data from a multi-stage through-diffusion and membrane behavior test,validating the accuracy of the proposed method.展开更多
BACKGROUND Sulongga-4(SL-4)is a herbal formula used in traditional Mongolian medical clinics for the treatment of peptic ulcers and gastroenteritis,even though its pharmacological mechanism has not been well character...BACKGROUND Sulongga-4(SL-4)is a herbal formula used in traditional Mongolian medical clinics for the treatment of peptic ulcers and gastroenteritis,even though its pharmacological mechanism has not been well characterized.AIM To evaluate the protective effect and identify the mechanisms of action of SL-4 on gastroduodenal ulcer induced by pyloric ligation(PL)in rats.METHODS PL was performed to induce gastric and duodenal ulcers in rats,which were then treated with oral SL-4(1.3,2.6,or 3.9 g/kg per day)for 15 d.PL-induced gastroduodenal ulceration.Therapeutic effects were characterized by pathological and histological evaluations and inflammatory indicators were analyzed by enzyme-linked immunosorbent assay.Microarray analyses were conducted to identify gene expression profiles of gastroduodenal tissue in PL rats with or without SL-4 treatment.The candidate target genes were selected and verified by quantitative reverse transcription polymerase chain reaction(qRT-PCR).RESULTS SL-4 decreased histopathological features in the PL-induced ulcerated rats.SL-4 significantly (P < 0.05) decreased expression of tumor necrosis factor-α,interleukin (IL)-1β, IL-6, endotoxin, platelet-activating factor, and increasedprostaglandin E2 and epidermal growth factor in ulcer tissue. Microarray analysiswas used to identify a panel of candidate target genes for SL-4 acting on PLinducedulceration. Genes included some complement and coagulation cascadeand retinol metabolism pathways that are closely associated with inflammatoryresponses and gastric mucosal protective mechanisms. qRT-PCR showed thataltered expression of the selected genes, such as CYP2b2, UGT2b1, A2m, andMASP1 was consistent with the microarray results.CONCLUSIONSL-4 exerts protective effects against PL-induced gastroduodenal ulcers viareducing inflammatory cytokines and elevating expression of gastric acidinhibitory factors. Downregulation of CYP2b2 and UGT2b1 genes in retinolmetabolism and upregulation of A2m and MASP1 genes in the complement andcoagulation cascades pathways are possibly involved in SL-4-mediated protectionagainst gastroduodenal ulcer.展开更多
为了解决Kumada催化剂转移缩聚(Kumada catalyst transfer polycondensation,KCTP)反应构建的聚噻吩材料结构单一、能级较高等问题,通过KCTP法成功实现了含有4个噻吩单元与硫醚侧链单体的聚合,构建了含有硫代烷基侧链的新型聚噻吩材料(P...为了解决Kumada催化剂转移缩聚(Kumada catalyst transfer polycondensation,KCTP)反应构建的聚噻吩材料结构单一、能级较高等问题,通过KCTP法成功实现了含有4个噻吩单元与硫醚侧链单体的聚合,构建了含有硫代烷基侧链的新型聚噻吩材料(PtTSBO),并通过控制氧化剂间氯过氧苯甲酸(m-CPBA)的用量和反应温度,将侧链上的硫醚选择性地氧化为亚砜或砜基,制备了含有亚砜或砜基的PtTSBO(PtTSOBO或PtTSOOBO)。通过核磁共振氢(1H-NMR)谱、元素分析(EA)、紫外-可见分光(UV-Vis)光谱和电化学(CV)曲线对聚合物的结构、吸光和电学性能进行了表征,并对所制备的光伏器件进行了光电性质研究。结果表明,这种后修饰策略有效地将硫醚官能团转变为强吸电子基团,相比于PtTSBO,聚合物PtTSOBO和PtTSOOBO的能级显著降低,相应光伏器件的开路电压(Voc)得到了提升。展开更多
A composite liner consisting of a geomembrane(GMB)and a geosynthetic clay liner(GCL)can be compromised by inorganic contaminants because of a defective GMB.When the composite liner with defective GMB is exposed to agg...A composite liner consisting of a geomembrane(GMB)and a geosynthetic clay liner(GCL)can be compromised by inorganic contaminants because of a defective GMB.When the composite liner with defective GMB is exposed to aggressive leachate conditions,the neglect of the chemical incompatibility of the GCL can potentially result in an underestimation of the leakage rate and flux through the composite liner.This paper proposed a numerical investigation on the effect of chemical incompatibility of GCL on the barrier performance of the composite liner with hole defect.Four cases with leachate solutions having varied cation valencies and ionic strengths were analyzed,in which the hydraulic conductivity of GCL was concentrationdependent.Both the effect of the chemical incompatibility of GCL and the mechanisms were analyzed.The incompatibility of GCL resulted in significant increases in leakage rate and flux through the composite liner by factors of up to 4.9 and 5.0,respectively.The incompatibility-affected area in GCL is located within 0.1 m from the center of the hole in the GMB.The coupled increase in the hydraulic conductivity of GCL and pore water concentration impacts the flux and leakage in a short period of time.With GCL chemical incompatibility considered,advection may dominate the contaminant transport through GCL.展开更多
基金The financial support received from the Ministry of Science and Technology of the People’s Republic of China(Grant No.2019YFC1806002)National Natural Science Foundation of China(Grant Nos.42107174,42077241)is gratefully acknowledged.
文摘The through-diffusion and membrane behavior testing procedure using a closed-system apparatus has been widely used for concurrent measurement of diffusion and membrane efficiency coefficients of low-permeability clay-based barrier materials.However,the common assumption of perfectly flushing conditions at the specimen boundaries could induce errors in analyses of the diffusion coefficients and membrane efficiencies.In this study,an innovative pseudo three-dimensional(3D)analytical method was proposed to evaluate solute distribution along the boundary surfaces of the soil-porous disks system,considering the non-perfectly flushing conditions.The results were consistent with numerical models under two scenarios considering different inflow/outflow positions.The proposed model has been demonstrated to be an accurate and reliable method to estimate solute distributions along the bound-aries.The calculated membrane efficiency coefficient and diffusion coefficient based on the proposed analytical method are more accurate,resulting in up to 50%less relative error than the traditional approach that adopts the arithmetic mean value of the influent and effluent concentrations.The retar-dation factor of the clay specimen also can be calculated with a revised cumulative mass approach.Finally,the simulated transient solute transport matched with experimental data from a multi-stage through-diffusion and membrane behavior test,validating the accuracy of the proposed method.
基金Mongolian Medicine Food and Drug Source Protection and Utilization Innovation Team Construction Project,No.190301National Natural Science Foundation of China,No.81760765+2 种基金Inner Mongolia University for Nationalities Doctoral Start-up Grant,No.BS412 and No.BS413Mongolian Medicine Engineering Technology Research Centre Open Fund Project,No.MDK2017072Inner Mongolia Autonomous Region Talent Development Fund Project,No.RC201802.
文摘BACKGROUND Sulongga-4(SL-4)is a herbal formula used in traditional Mongolian medical clinics for the treatment of peptic ulcers and gastroenteritis,even though its pharmacological mechanism has not been well characterized.AIM To evaluate the protective effect and identify the mechanisms of action of SL-4 on gastroduodenal ulcer induced by pyloric ligation(PL)in rats.METHODS PL was performed to induce gastric and duodenal ulcers in rats,which were then treated with oral SL-4(1.3,2.6,or 3.9 g/kg per day)for 15 d.PL-induced gastroduodenal ulceration.Therapeutic effects were characterized by pathological and histological evaluations and inflammatory indicators were analyzed by enzyme-linked immunosorbent assay.Microarray analyses were conducted to identify gene expression profiles of gastroduodenal tissue in PL rats with or without SL-4 treatment.The candidate target genes were selected and verified by quantitative reverse transcription polymerase chain reaction(qRT-PCR).RESULTS SL-4 decreased histopathological features in the PL-induced ulcerated rats.SL-4 significantly (P < 0.05) decreased expression of tumor necrosis factor-α,interleukin (IL)-1β, IL-6, endotoxin, platelet-activating factor, and increasedprostaglandin E2 and epidermal growth factor in ulcer tissue. Microarray analysiswas used to identify a panel of candidate target genes for SL-4 acting on PLinducedulceration. Genes included some complement and coagulation cascadeand retinol metabolism pathways that are closely associated with inflammatoryresponses and gastric mucosal protective mechanisms. qRT-PCR showed thataltered expression of the selected genes, such as CYP2b2, UGT2b1, A2m, andMASP1 was consistent with the microarray results.CONCLUSIONSL-4 exerts protective effects against PL-induced gastroduodenal ulcers viareducing inflammatory cytokines and elevating expression of gastric acidinhibitory factors. Downregulation of CYP2b2 and UGT2b1 genes in retinolmetabolism and upregulation of A2m and MASP1 genes in the complement andcoagulation cascades pathways are possibly involved in SL-4-mediated protectionagainst gastroduodenal ulcer.
文摘为了解决Kumada催化剂转移缩聚(Kumada catalyst transfer polycondensation,KCTP)反应构建的聚噻吩材料结构单一、能级较高等问题,通过KCTP法成功实现了含有4个噻吩单元与硫醚侧链单体的聚合,构建了含有硫代烷基侧链的新型聚噻吩材料(PtTSBO),并通过控制氧化剂间氯过氧苯甲酸(m-CPBA)的用量和反应温度,将侧链上的硫醚选择性地氧化为亚砜或砜基,制备了含有亚砜或砜基的PtTSBO(PtTSOBO或PtTSOOBO)。通过核磁共振氢(1H-NMR)谱、元素分析(EA)、紫外-可见分光(UV-Vis)光谱和电化学(CV)曲线对聚合物的结构、吸光和电学性能进行了表征,并对所制备的光伏器件进行了光电性质研究。结果表明,这种后修饰策略有效地将硫醚官能团转变为强吸电子基团,相比于PtTSBO,聚合物PtTSOBO和PtTSOOBO的能级显著降低,相应光伏器件的开路电压(Voc)得到了提升。
基金supported by the National Key Research and Development Program of China(Nos.2018YFC1802304 and 2019YFC1806002)the National Natural Science Foundation of China(Nos.42077241 and 51988101)。
文摘A composite liner consisting of a geomembrane(GMB)and a geosynthetic clay liner(GCL)can be compromised by inorganic contaminants because of a defective GMB.When the composite liner with defective GMB is exposed to aggressive leachate conditions,the neglect of the chemical incompatibility of the GCL can potentially result in an underestimation of the leakage rate and flux through the composite liner.This paper proposed a numerical investigation on the effect of chemical incompatibility of GCL on the barrier performance of the composite liner with hole defect.Four cases with leachate solutions having varied cation valencies and ionic strengths were analyzed,in which the hydraulic conductivity of GCL was concentrationdependent.Both the effect of the chemical incompatibility of GCL and the mechanisms were analyzed.The incompatibility of GCL resulted in significant increases in leakage rate and flux through the composite liner by factors of up to 4.9 and 5.0,respectively.The incompatibility-affected area in GCL is located within 0.1 m from the center of the hole in the GMB.The coupled increase in the hydraulic conductivity of GCL and pore water concentration impacts the flux and leakage in a short period of time.With GCL chemical incompatibility considered,advection may dominate the contaminant transport through GCL.
