Ultrafine polycaprolactone(PCL)fibers containing watersoluble drug tetracycline hydrochloride(Tet)were prepared by emulsion electrospinning.Sorbitan monooleate(Span80)was added as an essential additive to form stable ...Ultrafine polycaprolactone(PCL)fibers containing watersoluble drug tetracycline hydrochloride(Tet)were prepared by emulsion electrospinning.Sorbitan monooleate(Span80)was added as an essential additive to form stable water/oil emulsions and fabricate fibers with core-sheath structure.Different concentrations of Span80(0-40 g/L)were used to investigate the stability of emulsion and size of dispersed droplets.The scanning electron microscope(SEM)images indicated that the morphology of the fibers with Span80 were beaded-free with diameters of 200-400 nm,and Span80 enhanced the spinnability of electrospinning solution.The laser scanning confocal microscope(LSCM)images indicated that Tet was well encapsulated into the core region of the PCL fibers.The transmission electron microscope(TEM)image showed the formation of core-sheath structure.The loading efficiency(LE)and entrapment efficiency(EE)of Tet were calculated and release profiles in artificial saliva buffer solution(pH=6.8)were also analyzed.The results revealed that LE and EE of fibers with Span80decreased with the increase of its concentration.Fibers with coresheath structure had a longer effective release lifetime than without Span80.The increase of Span80 resulted in higher hydrophilicity of fibers and faster release rate of Tet.展开更多
Bowl-like poly (styrene-co-glycidyl methacrylate) was synthesized by swollen seeded emulsion polymerization. The polymerization was carried out in PS seed emulsion swollen by toluene, whereby the bowl-like particles f...Bowl-like poly (styrene-co-glycidyl methacrylate) was synthesized by swollen seeded emulsion polymerization. The polymerization was carried out in PS seed emulsion swollen by toluene, whereby the bowl-like particles formed at last. The shape was observed by SEM. These particles became ball-like when swollen by toluene, observed by optical microscope, and the release behavior of solvent from them was examined.展开更多
Co-pyrolysis of coal and seaweed can not only effectively decrease the carbon footprint but also improve the quality and output of coal pyrolysis products,however,the influence of seaweed on thermal releasing behavior...Co-pyrolysis of coal and seaweed can not only effectively decrease the carbon footprint but also improve the quality and output of coal pyrolysis products,however,the influence of seaweed on thermal releasing behaviors of mercury during co-pyrolysis process are still unclear.In this work,the chlorella and Guizhou bituminous coal were mixed and used to reveal the mercury release behavior during co-pyrolysis by the temperature programmed pyrolysis experiments,thermogravimetric and differential thermogravimetric analysis(TG-DTG)and thermogravimetry-mass spectrometry(TG-MS)methods,offering a sufficient explanation on the control technology of mercury pollutants in co-pyrolysis.The results exhibited that a large amount of reducing gases such as CO,H_(2) and H_(2)O were generated in chlorella at the temperature range of 100-500℃,which was favorable for the transformation from oxidized mercury to elemental mercury,thus remarkably increased the release of elemental mercury in the raw coal sample.The mixed chlorella also significantly lowered the decomposition temperature range(from 400-600 to 300-400℃)of pyrite-bound mercury and decreased the decomposition temperatures of the pyrite-bound mercury species.Additionally,in the copyrolysis about 91.82%of mercury was released into the gas phase below 400℃ and was 13.77% higher than that of in individual pyrolysis of coal.展开更多
The concentrations and chemical forms of copper(Cu) and zinc(Zn) in surface soils directly influence the movement of Cu and Zn. In this study, thirteen sandy soil samples with a wide range of total Cu and Zn concentra...The concentrations and chemical forms of copper(Cu) and zinc(Zn) in surface soils directly influence the movement of Cu and Zn. In this study, thirteen sandy soil samples with a wide range of total Cu and Zn concentrations were collected for evaluating the relationships between Cu and Zn release and extraction time, ratio of soil to water, pH and electrolyte types. The results indicated that Cu released in batch extraction that represents long-term leaching was mainly from exchangeable, and carbonate bound Cu fractions, and Zn released in the batch extraction was mainly from its carbonate bound fraction. However, the Cu and Zn leached from the soils using the column leaching that represents short-term leaching were mainly from their exchangeable fractions. Soil column leaching at different pH values indicated that the amounts of leached Zn and Cu were greatly affected by pH. The Cu and Zn release experiments with varying extraction times and ratio of soil to water suggest that long-term water-logging in the soils after rain may increase contact time of the soils with water and the release of Cu and Zn to water from the soils, and total amounts of Cu or Zn released from the soils increase, but the Cu or Zn concentration in the surface runoff decrease with increasing rainfall intensity. The increased Ca concentration in soil solution increased stability of organic matter-mineral complexes and might decrease the dissolution of organic matter, and thus decreased the release of Cu-binding component of organic matter. However, high concentration of Na in the soil solution increased the dispersion of the organic matter-mineral complexes and increased dissolution of organic matter and the release of Cu from the soils.展开更多
Poly(styrene-glycidyl methacrylate) particles having bowl-shaped hollow structures were synthesized by swollen seed emulsion polymerization. The PS emulsion synthesized through soap-free emulsion polymerization was sw...Poly(styrene-glycidyl methacrylate) particles having bowl-shaped hollow structures were synthesized by swollen seed emulsion polymerization. The PS emulsion synthesized through soap-free emulsion polymerization was swollen by toluene, and then the mixture of second monomers was added under polymerization condition. So a thin shell of poly(styrene-glycidyl methacrylate) cross-linked by triethylene glycol diacrylate was formed around the swollen PS particle. The bowl-shaped particles were obtained after the collapsing of the thin shell when the toluene emanated from the particles, but the shapes were effected by the degrees of cross-linking. The shape of the particles was observed by SEM. The release behavior of solvent from the particles was examined by TG.展开更多
Due to the harsh conditions in the Qinghai-Tibetan Plateau in China,indigenous people have deep compassion on lives.Therefore,animal release has become a traditional activity praying for blessings.However,irrational r...Due to the harsh conditions in the Qinghai-Tibetan Plateau in China,indigenous people have deep compassion on lives.Therefore,animal release has become a traditional activity praying for blessings.However,irrational release behaviors have become increasingly commonthey blindly pursue the number and species of animals to be released while ignoring their adaptability to the release habitats,creating a vicious cycle of"release-capture-sell"and raising people's and human-nature conflicts.This study focuses on the lower Lhasa River valley in south-central Xizang in China and proposed a collaborative life protection plan with respect of local culture.Through in-depth analysis of the needs of different stakeholders,this study established a new cooperative relationship,where the Tibetan Farmers'and Herdsmen's Economic Cooperatives would function as the core to standardize the trading process and promote scientific animal release.Based on the habitat suitability evaluation,this study developed release process optimization,habitat planning for released species,and ecological restoration planning to build the landscape structure of"vegetation-sacred place-life release spots"for environmental sustainability.This collaborative life protection plan contributes to establishing a healthier,harmonious,equal,and loving values on life and interpersonal relationships,thereby bringing about more profound social,economic,and environmental benefits.展开更多
AIM： To investigate the effect of release behavior of sustained-release dosage forms of sinomenine hydrochloride （SM·HCl） on its pharmacokinetics in beagle dogs. METHODS： The in vitro release behavior of two ...AIM： To investigate the effect of release behavior of sustained-release dosage forms of sinomenine hydrochloride （SM·HCl） on its pharmacokinetics in beagle dogs. METHODS： The in vitro release behavior of two SM·HCl dosage forms, including commercial 12-h sustained-release tablets and 24-h sustained-release pellets prepared in our laboratory, was examined. The two dosage forms were orally administrated to beagle dogs, and then the in vivo SM.HCI pharmacokinetics was investigated and compared. RESULTS： The optimal SM·HCl sustained-release formulation was achieved by mixing slow- and rapidrelease pellets （9：1, w/w）. The SM·HCl release profiles of the sustained-release pellets were scarcely influenced by the pH of the dissolution medium. Release from the 12-h sustained-release tablets was markedly quicker than that from the 24-h sustained-release pellets, the cumulative release up to 12-h was 99.9% vs68.7%. From a pharmacokinetic standpoint, the 24-h SM.HCI sustainedrelease pellets had longer tmax and lower Cmax compared to the 12-h sustained-release tablets, the tmax being 2.67±0.52 h vs 9.83±0.98 h and the Cmax being 1334.45±368.76 ng/mL vs 893.12±292.55 ng/mL, respectively. However, the AUC0-tn of two SM·HCl dosage forms was comparable and both preparations were statistically bioequivalent. Furthermore, the two preparations had good correlations between SM·HCl percentage absorption in vivoand the cumulative percentage release in vitro. CONCLUSION： The in vitro release properties of the dosage forms strongly affect their pharmacokinetic behavior in vivo. Therefore, managing the in vitro release behavior of dosage forms is a promising strategy for obtaining the optimal in vivo pharmacokinetic characteristics and safe therapeutic drug concentration-time curves.展开更多
Special attention was drawn to the heavy metals contained in coal,due to it will cause harm to the environment during coal processing and utilization.The sequential chemical extraction of Shanxi coal(SX coal)and Wulan...Special attention was drawn to the heavy metals contained in coal,due to it will cause harm to the environment during coal processing and utilization.The sequential chemical extraction of Shanxi coal(SX coal)and Wulanchabu coal(WLCB coal)was carried out to investigate the distribution of arsenic(As)in coals.Two raw coals were pyrolyzed at 300-900℃ in horizontal tubular furnace to investigate release behavior of As during pyrolysis process.The results showed that As in SX coal mainly existed in aluminosilicate-bound state(40.25%)and disulfide-bound state(32.51%),followed by carbonate-bound state and organic-bound state.The As in WLCB coal mainly existed in aluminosilicate-bound state(62.50%),followed by disulfide-bound state(19.10%).The As contents of water-soluble,ion-exchange and residue states in the two coals were less than others.The modes of occurrence of As had great infuence on its volatilization behavior.As in organic part was easy to volatilize at low temperature.Sulfide-bound state would escape with the decomposition of pyrite.Because SX coal contained higher organic state and sulfide-bound state,the volatilization rate of As was higher than WLCB coal at any temperature,and the difference was more obvious at low temperature.In addition,FactSage simulation value was basically consistent with the experimental value.展开更多
Lead(Pb) coprecipitation with jarosite is common in natural and engineered environments,such as acid mine drainage(AMD) sites and hydrometallurgical industry. Despite the high relevance for environmental impact, few s...Lead(Pb) coprecipitation with jarosite is common in natural and engineered environments,such as acid mine drainage(AMD) sites and hydrometallurgical industry. Despite the high relevance for environmental impact, few studies have examined the exact interaction of Pb with jarosite and the dissolution behavior of each phase. In the present work, we demonstrate that Pb mainly interacts with jarosite in four modes, namely incorporation, occlusion,physically mixing, and chemically mixing. For comparison, the four modes of Pb-bearing natrojarosite were synthesized and characterized separately. Batch dissolution experiments were undertaken on these synthetic Pb-bearing natrojarosites under pH_(2) to simulate the AMD environments. The introduction of Pb decreases the final Fe releasing efficiency of jarosite-type compounds from 18.18% to 3.45%-5.01%, showing a remarkable inhibition of their dissolution. For Pb releasing behavior, PbSO_(4) dissolves in preference to Pb-substituted natrojarosite, i.e.,(Na, Pb)-jarosite, which primarily results in the sharp increase of Pb releasing concentration(> 40 mg/L). PbSO_(4) occlusion by jarosite-type compounds can significantly reduce the release of Pb. The results of this study could provide useful information regarding Fe and Pb cycling in acidic natural and engineered environments.展开更多
Measurements of free surface velocity profiles of high-purity Zr samples under shock-wave loading are performed to study the dynamic strength and phase transition parameters. The peak pressure of the compression waves...Measurements of free surface velocity profiles of high-purity Zr samples under shock-wave loading are performed to study the dynamic strength and phase transition parameters. The peak pressure of the compression waves is within the range from 9 to 14 GPa, and the Hugoniot elastic limit is 0.5 GPa. An anomalous structure of shock waves is observed due to the α - ω phase transition in Zr. Shock pressure has effects on transition pressure which increases with increasing compression strength, and the stronger shocks have a lower transit time.展开更多
This study investigates the use of struviterient-loaded magnesium-modified biochar beads(Ca/MgBC+NP)as a slow-release fertilizer and soil amendment,comparing its performance with commercially available slow-release fe...This study investigates the use of struviterient-loaded magnesium-modified biochar beads(Ca/MgBC+NP)as a slow-release fertilizer and soil amendment,comparing its performance with commercially available slow-release fertilizers(SRF)in different soils and crop types.The results demonstrate that Ca/MgBC+NP exhibited satisfying swelling,water retention,and slow-release properties in all tested soils.In sandy soil,which showed the most significant differences(p<0.05),Ca/MgBC+NP enhanced the growth of Brassica chinensis L.and Spinacia oleracea L.after 90 d,with shoot and root lengths,as well as fresh and dry weights,1.25-2.84 times higher than those treated with SRF.The cation exchange capacity and organic carbon content of sandy soil were significantly improved(by 38.55%and 265.38%),overcoming its natural limitations in water and fertilizer retention.Principal Component Analysis(PCA)confirmed that soil properties played a crucial role in crop growth(52.67%variance explained).Spectroscopic analysis indicated that magnesium-related compounds,including struvite and Mg(PO_(4))_(3),contributed to the observed growth promotion.Furthermore,Ca/MgBC+NP effectively immobilized heavy metals,particularly Cr and Hg,with immobilization rates exceeding 80%.This study highlights the potential of Ca/MgBC+NP as a sustainable,low-cost fertilizer that not only enhances crop growth but also improves soil health and remediates heavy metal contamination,providing a promising alternative for green agriculture.展开更多
The control ofblack and odorous substances in sediments is of crucial importance to improve the urban ecological landscape and to restore water environments accordingly.In this study,chemical oxidation by the oxidants...The control ofblack and odorous substances in sediments is of crucial importance to improve the urban ecological landscape and to restore water environments accordingly.In this study,chemical oxidation by the oxidants NaClO,H2O2,and KMnO4 was proposed to achieve rapid control of black and odorous substances in heavily-polluted sediments.Results indicate that NaClO and KMnO4 are effective at removing Fe(II)and acid volatile sulfides.The removal efficiencies of Fe(II)and AVS were determined to be 45.2%,94.1%,and 93.7%,89.5%after 24-h exposure to NaClO and KMnO4 at 0.2 mmol/g,respectively.Additionally,rapid oxidation might accelerate the release of pollutants from sediment.The release of organic matters and phosphorus with the maximum ratios of 22.1%and 51.2%was observed upon NaClO oxidation at 0.4 mmol/g.Moreover,the introduction of oxidants contributed to changes in the microbial community composition in sediment.After oxidation by NaClO and KMnO4 at 0.4 mmol/g,the Shannon index decreased from 6.72 to 5.19 and 4.95,whereas the OTU numbers decreased from 2904 to 1677 and 1553,respectively.Comparatively,H2O2 showed a lower effect on the removal of black and odorous substances,pollutant release,and changes in sediment microorganisms.This study illustrates the effects of oxidant addition on the characteristics of heavily polluted sediments and shows that chemical oxidants may be an option to achieve rapid control of black and odorous substances prior to remediation of water environments.展开更多
Edible film combined with nanotechnology is one of the strategies of food intelligent packaging to extend food shelf life.Herein,eugenol-loaded sodium caseinate and trimethyl chitosan composite nanoparticles(ESTNPs)we...Edible film combined with nanotechnology is one of the strategies of food intelligent packaging to extend food shelf life.Herein,eugenol-loaded sodium caseinate and trimethyl chitosan composite nanoparticles(ESTNPs)were firstly prepared to improve bioavailability and stability.Subsequently,gelatin films loaded with ESTNPs were fabricated,and microscopic results showed good biocompatibility between nanoparticles and gelatin.The incorporation of ESTNPs significantly improved the light/water/oxygen barrier properties and thermal stability of the film(p<0.05),while it weakened the mechanical performance.ESTNPs endowed the film with excellent antibacterial efficiency(exceeded 99.99%)and enhanced its antioxidant activity.The ESTNPs/gelatin composite film exhibited good storage stability.The release behavior of eugenol from the film indicated that the composite film was more suitable for acidic foods,which could be used for meat packaging.Results in the antibacterial and preservation tests on chicken breast meat confirmed that the composite film could indeed serve as an active food packaging film for extending the shelf life of the meat without side-effect on the chroma,texture and sense quality.Hence,the prepared edible film combined with ESTNPs has great potential in extending food shelf life and provide a strategy for the preparation of active packaging.展开更多
基金“111 Project” Biomedical Textile Materials Science and Technology,China(No.B07024)
文摘Ultrafine polycaprolactone(PCL)fibers containing watersoluble drug tetracycline hydrochloride(Tet)were prepared by emulsion electrospinning.Sorbitan monooleate(Span80)was added as an essential additive to form stable water/oil emulsions and fabricate fibers with core-sheath structure.Different concentrations of Span80(0-40 g/L)were used to investigate the stability of emulsion and size of dispersed droplets.The scanning electron microscope(SEM)images indicated that the morphology of the fibers with Span80 were beaded-free with diameters of 200-400 nm,and Span80 enhanced the spinnability of electrospinning solution.The laser scanning confocal microscope(LSCM)images indicated that Tet was well encapsulated into the core region of the PCL fibers.The transmission electron microscope(TEM)image showed the formation of core-sheath structure.The loading efficiency(LE)and entrapment efficiency(EE)of Tet were calculated and release profiles in artificial saliva buffer solution(pH=6.8)were also analyzed.The results revealed that LE and EE of fibers with Span80decreased with the increase of its concentration.Fibers with coresheath structure had a longer effective release lifetime than without Span80.The increase of Span80 resulted in higher hydrophilicity of fibers and faster release rate of Tet.
文摘Bowl-like poly (styrene-co-glycidyl methacrylate) was synthesized by swollen seeded emulsion polymerization. The polymerization was carried out in PS seed emulsion swollen by toluene, whereby the bowl-like particles formed at last. The shape was observed by SEM. These particles became ball-like when swollen by toluene, observed by optical microscope, and the release behavior of solvent from them was examined.
基金supported by the Natural Science Foundation of Shandong Province (No. ZR2019MEE023)the Qingchuang Science and Technology Program of Shandong Province University (No. 2019KJD004)the National Natural Science Foundation of China (Nos. 22078168 and 21776164)。
文摘Co-pyrolysis of coal and seaweed can not only effectively decrease the carbon footprint but also improve the quality and output of coal pyrolysis products,however,the influence of seaweed on thermal releasing behaviors of mercury during co-pyrolysis process are still unclear.In this work,the chlorella and Guizhou bituminous coal were mixed and used to reveal the mercury release behavior during co-pyrolysis by the temperature programmed pyrolysis experiments,thermogravimetric and differential thermogravimetric analysis(TG-DTG)and thermogravimetry-mass spectrometry(TG-MS)methods,offering a sufficient explanation on the control technology of mercury pollutants in co-pyrolysis.The results exhibited that a large amount of reducing gases such as CO,H_(2) and H_(2)O were generated in chlorella at the temperature range of 100-500℃,which was favorable for the transformation from oxidized mercury to elemental mercury,thus remarkably increased the release of elemental mercury in the raw coal sample.The mixed chlorella also significantly lowered the decomposition temperature range(from 400-600 to 300-400℃)of pyrite-bound mercury and decreased the decomposition temperatures of the pyrite-bound mercury species.Additionally,in the copyrolysis about 91.82%of mercury was released into the gas phase below 400℃ and was 13.77% higher than that of in individual pyrolysis of coal.
文摘The concentrations and chemical forms of copper(Cu) and zinc(Zn) in surface soils directly influence the movement of Cu and Zn. In this study, thirteen sandy soil samples with a wide range of total Cu and Zn concentrations were collected for evaluating the relationships between Cu and Zn release and extraction time, ratio of soil to water, pH and electrolyte types. The results indicated that Cu released in batch extraction that represents long-term leaching was mainly from exchangeable, and carbonate bound Cu fractions, and Zn released in the batch extraction was mainly from its carbonate bound fraction. However, the Cu and Zn leached from the soils using the column leaching that represents short-term leaching were mainly from their exchangeable fractions. Soil column leaching at different pH values indicated that the amounts of leached Zn and Cu were greatly affected by pH. The Cu and Zn release experiments with varying extraction times and ratio of soil to water suggest that long-term water-logging in the soils after rain may increase contact time of the soils with water and the release of Cu and Zn to water from the soils, and total amounts of Cu or Zn released from the soils increase, but the Cu or Zn concentration in the surface runoff decrease with increasing rainfall intensity. The increased Ca concentration in soil solution increased stability of organic matter-mineral complexes and might decrease the dissolution of organic matter, and thus decreased the release of Cu-binding component of organic matter. However, high concentration of Na in the soil solution increased the dispersion of the organic matter-mineral complexes and increased dissolution of organic matter and the release of Cu from the soils.
文摘Poly(styrene-glycidyl methacrylate) particles having bowl-shaped hollow structures were synthesized by swollen seed emulsion polymerization. The PS emulsion synthesized through soap-free emulsion polymerization was swollen by toluene, and then the mixture of second monomers was added under polymerization condition. So a thin shell of poly(styrene-glycidyl methacrylate) cross-linked by triethylene glycol diacrylate was formed around the swollen PS particle. The bowl-shaped particles were obtained after the collapsing of the thin shell when the toluene emanated from the particles, but the shapes were effected by the degrees of cross-linking. The shape of the particles was observed by SEM. The release behavior of solvent from the particles was examined by TG.
文摘Due to the harsh conditions in the Qinghai-Tibetan Plateau in China,indigenous people have deep compassion on lives.Therefore,animal release has become a traditional activity praying for blessings.However,irrational release behaviors have become increasingly commonthey blindly pursue the number and species of animals to be released while ignoring their adaptability to the release habitats,creating a vicious cycle of"release-capture-sell"and raising people's and human-nature conflicts.This study focuses on the lower Lhasa River valley in south-central Xizang in China and proposed a collaborative life protection plan with respect of local culture.Through in-depth analysis of the needs of different stakeholders,this study established a new cooperative relationship,where the Tibetan Farmers'and Herdsmen's Economic Cooperatives would function as the core to standardize the trading process and promote scientific animal release.Based on the habitat suitability evaluation,this study developed release process optimization,habitat planning for released species,and ecological restoration planning to build the landscape structure of"vegetation-sacred place-life release spots"for environmental sustainability.This collaborative life protection plan contributes to establishing a healthier,harmonious,equal,and loving values on life and interpersonal relationships,thereby bringing about more profound social,economic,and environmental benefits.
文摘AIM： To investigate the effect of release behavior of sustained-release dosage forms of sinomenine hydrochloride （SM·HCl） on its pharmacokinetics in beagle dogs. METHODS： The in vitro release behavior of two SM·HCl dosage forms, including commercial 12-h sustained-release tablets and 24-h sustained-release pellets prepared in our laboratory, was examined. The two dosage forms were orally administrated to beagle dogs, and then the in vivo SM.HCI pharmacokinetics was investigated and compared. RESULTS： The optimal SM·HCl sustained-release formulation was achieved by mixing slow- and rapidrelease pellets （9：1, w/w）. The SM·HCl release profiles of the sustained-release pellets were scarcely influenced by the pH of the dissolution medium. Release from the 12-h sustained-release tablets was markedly quicker than that from the 24-h sustained-release pellets, the cumulative release up to 12-h was 99.9% vs68.7%. From a pharmacokinetic standpoint, the 24-h SM.HCI sustainedrelease pellets had longer tmax and lower Cmax compared to the 12-h sustained-release tablets, the tmax being 2.67±0.52 h vs 9.83±0.98 h and the Cmax being 1334.45±368.76 ng/mL vs 893.12±292.55 ng/mL, respectively. However, the AUC0-tn of two SM·HCl dosage forms was comparable and both preparations were statistically bioequivalent. Furthermore, the two preparations had good correlations between SM·HCl percentage absorption in vivoand the cumulative percentage release in vitro. CONCLUSION： The in vitro release properties of the dosage forms strongly affect their pharmacokinetic behavior in vivo. Therefore, managing the in vitro release behavior of dosage forms is a promising strategy for obtaining the optimal in vivo pharmacokinetic characteristics and safe therapeutic drug concentration-time curves.
基金supported by the National Natural Science Foundation of China(52304311 and 52274282)Yue Qi Young Scholar Project,China University of Mining&Technology,Beijing(2020QN10).
文摘Special attention was drawn to the heavy metals contained in coal,due to it will cause harm to the environment during coal processing and utilization.The sequential chemical extraction of Shanxi coal(SX coal)and Wulanchabu coal(WLCB coal)was carried out to investigate the distribution of arsenic(As)in coals.Two raw coals were pyrolyzed at 300-900℃ in horizontal tubular furnace to investigate release behavior of As during pyrolysis process.The results showed that As in SX coal mainly existed in aluminosilicate-bound state(40.25%)and disulfide-bound state(32.51%),followed by carbonate-bound state and organic-bound state.The As in WLCB coal mainly existed in aluminosilicate-bound state(62.50%),followed by disulfide-bound state(19.10%).The As contents of water-soluble,ion-exchange and residue states in the two coals were less than others.The modes of occurrence of As had great infuence on its volatilization behavior.As in organic part was easy to volatilize at low temperature.Sulfide-bound state would escape with the decomposition of pyrite.Because SX coal contained higher organic state and sulfide-bound state,the volatilization rate of As was higher than WLCB coal at any temperature,and the difference was more obvious at low temperature.In addition,FactSage simulation value was basically consistent with the experimental value.
基金supported by the National Natural Science Foundation of China for Distinguished Young Scholars (No. 51825403)the National Natural Science Foundation of China (No. 51904355)the National Key R&D Program of China (No. 2020YFC1909201)。
文摘Lead(Pb) coprecipitation with jarosite is common in natural and engineered environments,such as acid mine drainage(AMD) sites and hydrometallurgical industry. Despite the high relevance for environmental impact, few studies have examined the exact interaction of Pb with jarosite and the dissolution behavior of each phase. In the present work, we demonstrate that Pb mainly interacts with jarosite in four modes, namely incorporation, occlusion,physically mixing, and chemically mixing. For comparison, the four modes of Pb-bearing natrojarosite were synthesized and characterized separately. Batch dissolution experiments were undertaken on these synthetic Pb-bearing natrojarosites under pH_(2) to simulate the AMD environments. The introduction of Pb decreases the final Fe releasing efficiency of jarosite-type compounds from 18.18% to 3.45%-5.01%, showing a remarkable inhibition of their dissolution. For Pb releasing behavior, PbSO_(4) dissolves in preference to Pb-substituted natrojarosite, i.e.,(Na, Pb)-jarosite, which primarily results in the sharp increase of Pb releasing concentration(> 40 mg/L). PbSO_(4) occlusion by jarosite-type compounds can significantly reduce the release of Pb. The results of this study could provide useful information regarding Fe and Pb cycling in acidic natural and engineered environments.
文摘Measurements of free surface velocity profiles of high-purity Zr samples under shock-wave loading are performed to study the dynamic strength and phase transition parameters. The peak pressure of the compression waves is within the range from 9 to 14 GPa, and the Hugoniot elastic limit is 0.5 GPa. An anomalous structure of shock waves is observed due to the α - ω phase transition in Zr. Shock pressure has effects on transition pressure which increases with increasing compression strength, and the stronger shocks have a lower transit time.
基金supported by the National Natural Science Foundation of China(Nos.51908457 and 52070155).
文摘This study investigates the use of struviterient-loaded magnesium-modified biochar beads(Ca/MgBC+NP)as a slow-release fertilizer and soil amendment,comparing its performance with commercially available slow-release fertilizers(SRF)in different soils and crop types.The results demonstrate that Ca/MgBC+NP exhibited satisfying swelling,water retention,and slow-release properties in all tested soils.In sandy soil,which showed the most significant differences(p<0.05),Ca/MgBC+NP enhanced the growth of Brassica chinensis L.and Spinacia oleracea L.after 90 d,with shoot and root lengths,as well as fresh and dry weights,1.25-2.84 times higher than those treated with SRF.The cation exchange capacity and organic carbon content of sandy soil were significantly improved(by 38.55%and 265.38%),overcoming its natural limitations in water and fertilizer retention.Principal Component Analysis(PCA)confirmed that soil properties played a crucial role in crop growth(52.67%variance explained).Spectroscopic analysis indicated that magnesium-related compounds,including struvite and Mg(PO_(4))_(3),contributed to the observed growth promotion.Furthermore,Ca/MgBC+NP effectively immobilized heavy metals,particularly Cr and Hg,with immobilization rates exceeding 80%.This study highlights the potential of Ca/MgBC+NP as a sustainable,low-cost fertilizer that not only enhances crop growth but also improves soil health and remediates heavy metal contamination,providing a promising alternative for green agriculture.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.51820105011,51578537 and 51778603)the Chinese Academy of Sciences(No.QYZDY-SSWDQC004).
文摘The control ofblack and odorous substances in sediments is of crucial importance to improve the urban ecological landscape and to restore water environments accordingly.In this study,chemical oxidation by the oxidants NaClO,H2O2,and KMnO4 was proposed to achieve rapid control of black and odorous substances in heavily-polluted sediments.Results indicate that NaClO and KMnO4 are effective at removing Fe(II)and acid volatile sulfides.The removal efficiencies of Fe(II)and AVS were determined to be 45.2%,94.1%,and 93.7%,89.5%after 24-h exposure to NaClO and KMnO4 at 0.2 mmol/g,respectively.Additionally,rapid oxidation might accelerate the release of pollutants from sediment.The release of organic matters and phosphorus with the maximum ratios of 22.1%and 51.2%was observed upon NaClO oxidation at 0.4 mmol/g.Moreover,the introduction of oxidants contributed to changes in the microbial community composition in sediment.After oxidation by NaClO and KMnO4 at 0.4 mmol/g,the Shannon index decreased from 6.72 to 5.19 and 4.95,whereas the OTU numbers decreased from 2904 to 1677 and 1553,respectively.Comparatively,H2O2 showed a lower effect on the removal of black and odorous substances,pollutant release,and changes in sediment microorganisms.This study illustrates the effects of oxidant addition on the characteristics of heavily polluted sediments and shows that chemical oxidants may be an option to achieve rapid control of black and odorous substances prior to remediation of water environments.
基金The State Key Laboratory of Utilization of Woody Oil Resource(Grant no.2019XK 2002)National Natural Science Foundation of China(Grant no.31972172)+1 种基金Natural Science Foundation of Jiangsu Province(Grant no.BK20201417 and BK20220522)Jiangsu Province Research Fund(Grant no.JNHB-131)funded this research.
文摘Edible film combined with nanotechnology is one of the strategies of food intelligent packaging to extend food shelf life.Herein,eugenol-loaded sodium caseinate and trimethyl chitosan composite nanoparticles(ESTNPs)were firstly prepared to improve bioavailability and stability.Subsequently,gelatin films loaded with ESTNPs were fabricated,and microscopic results showed good biocompatibility between nanoparticles and gelatin.The incorporation of ESTNPs significantly improved the light/water/oxygen barrier properties and thermal stability of the film(p<0.05),while it weakened the mechanical performance.ESTNPs endowed the film with excellent antibacterial efficiency(exceeded 99.99%)and enhanced its antioxidant activity.The ESTNPs/gelatin composite film exhibited good storage stability.The release behavior of eugenol from the film indicated that the composite film was more suitable for acidic foods,which could be used for meat packaging.Results in the antibacterial and preservation tests on chicken breast meat confirmed that the composite film could indeed serve as an active food packaging film for extending the shelf life of the meat without side-effect on the chroma,texture and sense quality.Hence,the prepared edible film combined with ESTNPs has great potential in extending food shelf life and provide a strategy for the preparation of active packaging.
