The modelling and optimization for the alkaline sulphide leaching of a complex copper concentrate containing 1.69% Sb and 0.14% Sn were studied.Response surface methodology,in combination with central composite face-c...The modelling and optimization for the alkaline sulphide leaching of a complex copper concentrate containing 1.69% Sb and 0.14% Sn were studied.Response surface methodology,in combination with central composite face-centred design（RSM-CCF）,was used to optimise the operating parameters.The leaching temperature,sulphide ion concentration and solid concentration were chosen as the variables,and the response parameters were antimony and tin recovery,and the time required to achieve 90% Sb dissolution.It was confirmed that the leaching process was strongly dependent on the reaction temperature as well as the sulphide ion concentration without any significant dependence on the solid concentration.Furthermore,a mathematical model was constructed to characterise the leaching behaviour.The results from the model allow identification of the most favourable leaching conditions.The model was validated experimentally,and the results show that the model is reliable and accurate in predicting the leaching process.展开更多
Doxorubicin(DOX)is a widely employed tumor therapy,yet its substantial toxic side effects pose a considerable challenge.Bletilla striata has demonstrated efficacy in preventing and treating these toxic side effects in...Doxorubicin(DOX)is a widely employed tumor therapy,yet its substantial toxic side effects pose a considerable challenge.Bletilla striata has demonstrated efficacy in preventing and treating these toxic side effects in clinical practice,with polysaccharides identified as the principal active component.In the present study,16 fractions of B.striata polysaccharides(BsPs)were extracted using diverse methods,including hot-water extraction(HWE),ultrasonic-assisted extraction(UAE),enzyme-assisted extraction(EAE),dilute acid-water extraction(ACWE),and dilute alkali-water extraction(ALWE).These extractions were subsequently precipitated at final ethanol concentrations of 80%and 95%,respectively.The investigation encompassed yields,total carbohydrate content(TCC),total protein content(TPC),preliminary structural properties,and anti-DOX myocardial cytotoxic activity.Results indicated that the extraction method significantly influenced the physicochemical properties,associated functional properties,and anti-DOX myocardial cytotoxic activity of BsPs.HWE and UAE yielded higher BsPs quantities.The relative molecular weight(RMW)distribution of BsPs differed notably between HWE or UAE,EAE,ACWE,and ALWE.The RMW of primary BsPs obtained from HWE and UAE(1.9×10^(7)-1.7×10^(7) Da)exceeded that from EAE(7.5×10^(3)-2.8×10^(4) Da)and ALWE(5.1×10^(4)-1.7×10^(4) Da),with smaller molecular weights primarily precipitated by higher ethanol concentrations.BsPs were composed of Man and Glu,with partial fractions containing small amounts of Gal or Ara,displaying varying molar ratios.Notably,BsPs from ACWE exhibited the most significant structural differences,lacking 1,4-α-D-Glcp and a triple-helical structure.Furthermore,BsPs obtained from HWE,UAE,and EAE demonstrated heightened anti-DOX myocardial cytotoxic activity compared to other methods.This study underscored the influence of extraction methods on BsPs’structure and myocardial protective activity,offering a foundation for exploring structural diversity and employing specific extraction methods to extract polysaccharides with robust myocardial protective properties efficiently.展开更多
文摘The modelling and optimization for the alkaline sulphide leaching of a complex copper concentrate containing 1.69% Sb and 0.14% Sn were studied.Response surface methodology,in combination with central composite face-centred design（RSM-CCF）,was used to optimise the operating parameters.The leaching temperature,sulphide ion concentration and solid concentration were chosen as the variables,and the response parameters were antimony and tin recovery,and the time required to achieve 90% Sb dissolution.It was confirmed that the leaching process was strongly dependent on the reaction temperature as well as the sulphide ion concentration without any significant dependence on the solid concentration.Furthermore,a mathematical model was constructed to characterise the leaching behaviour.The results from the model allow identification of the most favourable leaching conditions.The model was validated experimentally,and the results show that the model is reliable and accurate in predicting the leaching process.
基金Science and Technology Foundation of Guizhou Province(Grant No.QKHJC-ZK[2023]YB524)Science and Technology Plan Project of Guizhou,China(Grant No.QKPTRC[2019]035)+2 种基金Science and Technology Foundation of Guizhou Province(Grant No.QKH[2019]1346)Science and Technology Department of Zunyi city of Guizhou province of China(Grant No.[2020]7)Undergraduate Training Program for Innovation and Entrepreneurship of Zunyi Medical University(Grant No.S202310661248).
文摘Doxorubicin(DOX)is a widely employed tumor therapy,yet its substantial toxic side effects pose a considerable challenge.Bletilla striata has demonstrated efficacy in preventing and treating these toxic side effects in clinical practice,with polysaccharides identified as the principal active component.In the present study,16 fractions of B.striata polysaccharides(BsPs)were extracted using diverse methods,including hot-water extraction(HWE),ultrasonic-assisted extraction(UAE),enzyme-assisted extraction(EAE),dilute acid-water extraction(ACWE),and dilute alkali-water extraction(ALWE).These extractions were subsequently precipitated at final ethanol concentrations of 80%and 95%,respectively.The investigation encompassed yields,total carbohydrate content(TCC),total protein content(TPC),preliminary structural properties,and anti-DOX myocardial cytotoxic activity.Results indicated that the extraction method significantly influenced the physicochemical properties,associated functional properties,and anti-DOX myocardial cytotoxic activity of BsPs.HWE and UAE yielded higher BsPs quantities.The relative molecular weight(RMW)distribution of BsPs differed notably between HWE or UAE,EAE,ACWE,and ALWE.The RMW of primary BsPs obtained from HWE and UAE(1.9×10^(7)-1.7×10^(7) Da)exceeded that from EAE(7.5×10^(3)-2.8×10^(4) Da)and ALWE(5.1×10^(4)-1.7×10^(4) Da),with smaller molecular weights primarily precipitated by higher ethanol concentrations.BsPs were composed of Man and Glu,with partial fractions containing small amounts of Gal or Ara,displaying varying molar ratios.Notably,BsPs from ACWE exhibited the most significant structural differences,lacking 1,4-α-D-Glcp and a triple-helical structure.Furthermore,BsPs obtained from HWE,UAE,and EAE demonstrated heightened anti-DOX myocardial cytotoxic activity compared to other methods.This study underscored the influence of extraction methods on BsPs’structure and myocardial protective activity,offering a foundation for exploring structural diversity and employing specific extraction methods to extract polysaccharides with robust myocardial protective properties efficiently.
