The integration of interfacial solar steam generation and photocatalytic degradation technology has pro-vided a promising platform to simultaneously produce freshwater and degrade pollutants.However,con-structing low-...The integration of interfacial solar steam generation and photocatalytic degradation technology has pro-vided a promising platform to simultaneously produce freshwater and degrade pollutants.However,con-structing low-cost,multi-functional evaporators for treating Cr(Ⅵ)-polluted water remains challenging,and the synergistic mechanism on Cr(Ⅵ)reduction is fuzzy.Herein,we propose the combined strategy of ball milling and solution mixing for the sustainable production of Bi-MOF microrod from waste poly(ethylene terephthalate),and construct Bi-MOF-based solar evaporators for simultaneous photo-Fenton Cr(Ⅵ)reduction and freshwater production.Firstly,the evaporator comprised of Bi-MOF microrod and graphene nanosheet possesses high light absorption,efficient photothermal conversion,and good hydro-philic property.Attributing to the advantages,the hybrid evaporator exhibits the evaporation rate of 2.16 kg m^(-2) h^(-1) and evaporation efficiency of 87.5%under 1 kW m^(-2) of irradiation.When integrating with photo-Fenton reaction,the Cr(Ⅵ)reduction efficiency is 91.3%,along with the reaction kinetics of 0.0548 min^(-1),surpassing many advanced catalysts.In the outdoor freshwater production and Cr(Ⅵ)reduction,the daily accumulative water yield is 5.17 kg m^(-2) h^(-1),and the Cr(Ⅵ)reduction efficiency is 99.9%.Furthermore,we prove that the localization effect derived from the interfacial solar-driven evap-oration enhances H_(2)O_(2) activation for the photo-Fenton reduction of Cr(Ⅵ).Based on the result of density functional theory,Bi-MOF microrod provides rich active centers for H_(2)O_(2) activation to produce active sites such as e-or-O_(2).This study not only proposes a new strategy to construct multi-functional solar evaporators for freshwater production and catalytic reduction of pollutants,but also advances the chem-ical upcycling of waste polyesters.展开更多
Specific and sustained release of nutrients from capsules to the gastrointestinal tract has attracted many attentions in the field of food and drug delivery.In this work,we reported a monoaxial dispersion electrospray...Specific and sustained release of nutrients from capsules to the gastrointestinal tract has attracted many attentions in the field of food and drug delivery.In this work,we reported a monoaxial dispersion electrospraying-ionotropic gelation technique to prepare multicore millimeter-sized spherical capsules for specific and sustained release of fish oil.The spherical capsules had diameters from 2.05 mm to 0.35 mm with the increased applied voltages.The capsules consisted of uniform(at applied voltages of≤10 k V)or nonuniform(at applied voltages of>10 k V)multicores.The obtained capsules had reasonable loading ratios(9.7%-6.3%)due to the multicore structure.In addition,the obtained capsules had specific and sustained release behaviors of fish oil into the small intestinal phase of in vitro gastrointestinal tract and small intestinal tract models.The simple monoaxial dispersion electrospraying-ionotropic gelatin technique does not involve complicated preparation formulations and polymer modification,which makes the technique has a potential application prospect for the fish oil preparations and the encapsulation of functional active substances in the field of food and drug industries.展开更多
Noise pollution is a major hazardous factor to human health and is likely harmful for vulnerable groups such as pre-term infants under lifesupport system in an intensive care unit. Previous studies have suggested that...Noise pollution is a major hazardous factor to human health and is likely harmful for vulnerable groups such as pre-term infants under lifesupport system in an intensive care unit. Previous studies have suggested that noise exposure impairs children’s learning ability and cognitive performance and cognitive functions in animal models in which the effect is mainly attributed to the oxidant stress of noise on the cognitive brain. The potential role of noise induced hearing loss(NIHL), rather than the oxidant stress, has also been indicated by a depression of neurogenesis in the hippocampus long after a brief noise exposure, which produces only a tentative oxidant stress. It is not clear if noise exposure and NIHL during early development exerts a long term impact on cognitive function and neurogenesis towards adulthood. In the present study, a brief noise exposure at high sound level was performed in neonatal C57BL/6J mice(15 days after birth) to produce a significant amount of permanent hearing loss as proved 2 months after the noise. At this age, the noise-exposed animals showed deteriorated spatial learning and memory abilities and a reduction of hippocampal neurogenesis as compared with the control. The averaged hearing threshold was found to be strongly correlated with the scores for spatial learning and memory. We consider the effects observed are largely due to the loss of hearing sensitivity, rather than the oxidant stress, due to the long interval between noise exposure and the observations.展开更多
A novel thiazolothiazole-bridged imidazole derivative(1) was found to exhibit blue fluorescence in gaseous state or in methanol and yellow fluorescence in solid state. The N-alkylation of imidazole subunit(s) in 1 usi...A novel thiazolothiazole-bridged imidazole derivative(1) was found to exhibit blue fluorescence in gaseous state or in methanol and yellow fluorescence in solid state. The N-alkylation of imidazole subunit(s) in 1 using n-propyl iodide generated unsymmetrically or symmetrically alkylated thiazolothiazolebridged imidazolium salts with good water solubility and remarkably strong emission in solution. Furthermore, the replacement of iodide counter-anion by triflate or bis(trifluoromethane sulfonyl)imide achieved remarkably strong emission in solid state and in solution as well as good water solubility. The strong fluorescence of dicationic salts with triflate and NTf_(2)^(-)counter-anions in solid state can be ascribed to their twisted and rigid structures induced by interionic C-H···F hydrogen bonding.展开更多
To understand the function of phosphoenolpyruvate carboxylase kinase,we introduced PtPEPCK1 gene under the control of 35S promoter into 84K poplar(Populus alba×P.glandulosa).PtPEPCK1 gene is well-known for its ro...To understand the function of phosphoenolpyruvate carboxylase kinase,we introduced PtPEPCK1 gene under the control of 35S promoter into 84K poplar(Populus alba×P.glandulosa).PtPEPCK1 gene is well-known for its role in gluconeogenesis.However,our data confi rmed that it has signifi cant eff ects on amino acid biosynthesis and nitrogen metabolism.Immunohistochemistry and fl uorescence microscopy indicate that PtPEPCK1 is specifi cally expressed in the cytoplasm of the spongy and palisade tissues.Overexpression of PtPEPCK1 was characterized through transcriptomics and metabolomics.The metabolites concentration of the ornithine cycle and its precursors also increased,of which N-acetylornithine was up-regulated almost 50-fold and ornithine 33.7-fold.These were accompanied by a massive increase in levels of several amino acids.Therefore,overexpression of PtPEPCK1 increases amino acid levels with urea cycle disorder.展开更多
Ginseng planting in Northeast China brings economic benefits but affects forest landscape integrity and native ecological processes.In order to quantify the impacts of ginseng planting on the forest landscape,Fusong C...Ginseng planting in Northeast China brings economic benefits but affects forest landscape integrity and native ecological processes.In order to quantify the impacts of ginseng planting on the forest landscape,Fusong County in Jilin Province was selected as a study area.The number and distribution of ginseng fields over different time was quantified based on remote sensing and ground surveys.Grid analysis and multiple regression analysis were used to study the impacts of ginseng planting on the landscape.The results showed that altitudes and slopes of ginseng fields increased and became increasingly scattered and smaller closer to the Changbai Mountain Nature Reserve.Ginseng fields and abandoned fields increased total patches and total area of the local forested landscape,and shared edge lengths between ginseng fields and forests,resulting in continuous fragmentation of the landscape.Although the total area of existing and abandoned ginseng fields accounts for a small fraction of the total landscape,their negative impacts on ecosystem conservation is significant.The local government needs to rationally plan ginseng planting,scientifically implement the restoration of abandoned ginseng lands,and enhance awareness of ginseng farmers to environmental stewardship.Our study has important significance for maintaining the healthy and stable development of the local ginseng industry and for improving the quality of regional ecological environment.展开更多
Correction to:J.For.Res.https://doi.org/10.1007/s11676-019-01042-4 In the Original publication,the author has found that C1 and C4 in Fig.3 have been published with errors.The corrected Fig.3 C1 and C4 are provided be...Correction to:J.For.Res.https://doi.org/10.1007/s11676-019-01042-4 In the Original publication,the author has found that C1 and C4 in Fig.3 have been published with errors.The corrected Fig.3 C1 and C4 are provided below.展开更多
The theoretical relationship between water injection multiple(i.e.injected pore volume)and water saturation is inferred from theoretical concepts of reservoir engineering.A mathematical model based on core displacemen...The theoretical relationship between water injection multiple(i.e.injected pore volume)and water saturation is inferred from theoretical concepts of reservoir engineering.A mathematical model based on core displacement tests is established for the entire injection process that satisfies both initial displacement and extreme displacement,simultaneously.The results show that prior to the flooding,the water injection multiple has a linear relationship with the water saturation,and the utilization rate of the injected water is the highest.As water breakthrough at the production end,the water-cut increases,and the injection multiple increases exponentially while the utilization efficiency of the injected water gradually decreases.When the injection multiple approaches infinity,the utilization efficiency of the injected water gradually decreases to 0,by which time the water-cut at the production end is always 1.At this time,the water saturation no longer changes,and the water flooding recovery rate reaches its limit.Based on the experimental test data,a mathematical model of the entire process of injection multiple and water saturation is established,which has high fitting accuracy that can predict the injection multiple in the different stages of development of a mature oil reservoir.The dynamically changing index of the injection water utilization efficiency in reservoir development by reactive water flooding can be obtained through reasonable transformation of the mathematical model.This is of great significance in guiding evaluations of the effects of reservoir development and formulating countermeasures.展开更多
Improving the complete ethanol electrooxidation on Pd-based catalysts in alkaline media has drawn widely attention due to the high mass energy density.However,the weak adsorption energy of CH_(3)CO^(*) on Pd restricts...Improving the complete ethanol electrooxidation on Pd-based catalysts in alkaline media has drawn widely attention due to the high mass energy density.However,the weak adsorption energy of CH_(3)CO^(*) on Pd restricts the C–C bond cleavage.Inspired by the molecular orbital theory,we proposed the d-state-editing strategy to construct more unoccupied d-states of Pd for the enhanced interaction with CH_(3)CO^(*) to break C–C bonds.As expected,the reduced number of e_g electrons and more unoccupied d-states of Pd successfully formed on as-prepared porous Rh Au–Pd Cu nanosheets(PNSs).Theoretical calculations show that the optimized d-states of Rh Au–Pd Cu PNS can effectively improve the adsorption of CH_(3)CO^(*) and drastically reduce the energy barrier of C–C bond cleavage,thus boosting the complete oxidation of ethanol.The charge ratio of C_1 pathway on Rh Au–Pd Cu PNSs is 51.5%,more than 2 times higher than that of Pd NSs.Our finding provides an innovative perspective for the design of highly-efficient noble-based electrocatalysts.展开更多
A new class of near-infrared(NIR)fluorescent organoboron AIEgens was successfully developed for latent fingerprints(LFPs)imaging.They exhibit real-time and in situ high-resolution imaging performance at 1-3 levels of ...A new class of near-infrared(NIR)fluorescent organoboron AIEgens was successfully developed for latent fingerprints(LFPs)imaging.They exhibit real-time and in situ high-resolution imaging performance at 1-3 levels of LFPs by spraying method.In addition,we systematically elucidate the fingerprint imaging mechanism of these AIEgens.Significantly,the excellent level 3 structural imaging capabilities enable the application of them for analyzing incomplete LFPs and identifying individuals in different scenarios.展开更多
Biochar shows significant potential to serve as a globally applicable material to remediate water and soil owing to the extensive availability of feedstocks and conducive physio-chemical surface characteristics.This r...Biochar shows significant potential to serve as a globally applicable material to remediate water and soil owing to the extensive availability of feedstocks and conducive physio-chemical surface characteristics.This review aims to highlight biochar production technologies,characteristics of biochar,and the latest advancements in immobilizing and eliminating heavy metal ions and organic pollutants in soil and water.Pyrolysis temperature,heat transfer rate,residence time,and type of feedstock are critical influential parameters.Biochar’s efficacy in managing contaminants relies on the pore size distribution,surface groups,and ion-exchange capacity.The molecular composition and physical architecture of biochar may be crucial when practically applied to water and soil.In general,biochar produced at relatively high pyrolysis temperatures can effectively manage organic pollutants via increasing surface area,hydrophobicity and microporosity.Biochar generated at lower temperatures is deemed to be more suitable for removing polar organic and inorganic pollutants through oxygen-containing functional groups,precipitation and electrostatic attraction.This review also presents the existing obstacles and future research direction related to biochar-based materials in immobilizing organic contaminants and heavy metal ions in effluents and soil.展开更多
Silk materials with different nanostructures have been developed without the understanding of the inherent transformation mechanism. Here we attempt to reveal the conversion road of the various nanostructures and dete...Silk materials with different nanostructures have been developed without the understanding of the inherent transformation mechanism. Here we attempt to reveal the conversion road of the various nanostructures and determine the critical regulating factors. The regulating conversion processes influenced by a hierarchical charge distribution were investigated, showing different transformations between molecules, nanoparticles and nanofibers. Various repulsion and compressive forces existed among silk fibroin molecules and aggregates due to the exterior and interior distribution of charge, which further controlled their aggregating and deaggregating behaviors and finally formed nanofibers with different sizes. Synergistic action derived from molecular mobility and concentrations could also tune the assembly process and final nanostructures, it is suggested that the complicated silk fibroin assembly processes comply a same rule based on charge distribution, offering a promising way to develop silk-based materials with designed nanostructures.展开更多
Dear Editor,Approximately 500 million individuals suffer from hearing loss worldwide. The number of hearing-impaired individuals is estimated to increase to 900 million by 2050. The etiology of hearing loss is complex.
基金supported by the National Natural Science Foundation of China(52373099)the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(B21003)。
文摘The integration of interfacial solar steam generation and photocatalytic degradation technology has pro-vided a promising platform to simultaneously produce freshwater and degrade pollutants.However,con-structing low-cost,multi-functional evaporators for treating Cr(Ⅵ)-polluted water remains challenging,and the synergistic mechanism on Cr(Ⅵ)reduction is fuzzy.Herein,we propose the combined strategy of ball milling and solution mixing for the sustainable production of Bi-MOF microrod from waste poly(ethylene terephthalate),and construct Bi-MOF-based solar evaporators for simultaneous photo-Fenton Cr(Ⅵ)reduction and freshwater production.Firstly,the evaporator comprised of Bi-MOF microrod and graphene nanosheet possesses high light absorption,efficient photothermal conversion,and good hydro-philic property.Attributing to the advantages,the hybrid evaporator exhibits the evaporation rate of 2.16 kg m^(-2) h^(-1) and evaporation efficiency of 87.5%under 1 kW m^(-2) of irradiation.When integrating with photo-Fenton reaction,the Cr(Ⅵ)reduction efficiency is 91.3%,along with the reaction kinetics of 0.0548 min^(-1),surpassing many advanced catalysts.In the outdoor freshwater production and Cr(Ⅵ)reduction,the daily accumulative water yield is 5.17 kg m^(-2) h^(-1),and the Cr(Ⅵ)reduction efficiency is 99.9%.Furthermore,we prove that the localization effect derived from the interfacial solar-driven evap-oration enhances H_(2)O_(2) activation for the photo-Fenton reduction of Cr(Ⅵ).Based on the result of density functional theory,Bi-MOF microrod provides rich active centers for H_(2)O_(2) activation to produce active sites such as e-or-O_(2).This study not only proposes a new strategy to construct multi-functional solar evaporators for freshwater production and catalytic reduction of pollutants,but also advances the chem-ical upcycling of waste polyesters.
基金supported by research grants from the National Key R&D Program(2019YFD0902003)。
文摘Specific and sustained release of nutrients from capsules to the gastrointestinal tract has attracted many attentions in the field of food and drug delivery.In this work,we reported a monoaxial dispersion electrospraying-ionotropic gelation technique to prepare multicore millimeter-sized spherical capsules for specific and sustained release of fish oil.The spherical capsules had diameters from 2.05 mm to 0.35 mm with the increased applied voltages.The capsules consisted of uniform(at applied voltages of≤10 k V)or nonuniform(at applied voltages of>10 k V)multicores.The obtained capsules had reasonable loading ratios(9.7%-6.3%)due to the multicore structure.In addition,the obtained capsules had specific and sustained release behaviors of fish oil into the small intestinal phase of in vitro gastrointestinal tract and small intestinal tract models.The simple monoaxial dispersion electrospraying-ionotropic gelatin technique does not involve complicated preparation formulations and polymer modification,which makes the technique has a potential application prospect for the fish oil preparations and the encapsulation of functional active substances in the field of food and drug industries.
基金supported by a grant from Nature Science Foundation of China (Grant#:81272086)
文摘Noise pollution is a major hazardous factor to human health and is likely harmful for vulnerable groups such as pre-term infants under lifesupport system in an intensive care unit. Previous studies have suggested that noise exposure impairs children’s learning ability and cognitive performance and cognitive functions in animal models in which the effect is mainly attributed to the oxidant stress of noise on the cognitive brain. The potential role of noise induced hearing loss(NIHL), rather than the oxidant stress, has also been indicated by a depression of neurogenesis in the hippocampus long after a brief noise exposure, which produces only a tentative oxidant stress. It is not clear if noise exposure and NIHL during early development exerts a long term impact on cognitive function and neurogenesis towards adulthood. In the present study, a brief noise exposure at high sound level was performed in neonatal C57BL/6J mice(15 days after birth) to produce a significant amount of permanent hearing loss as proved 2 months after the noise. At this age, the noise-exposed animals showed deteriorated spatial learning and memory abilities and a reduction of hippocampal neurogenesis as compared with the control. The averaged hearing threshold was found to be strongly correlated with the scores for spatial learning and memory. We consider the effects observed are largely due to the loss of hearing sensitivity, rather than the oxidant stress, due to the long interval between noise exposure and the observations.
基金National Natural Science Foundation of China(Nos.U20041101,21772034,U1704251)the Top-notch Personnel Fund of Henan Agricultural University(No.30500418)for financial support。
文摘A novel thiazolothiazole-bridged imidazole derivative(1) was found to exhibit blue fluorescence in gaseous state or in methanol and yellow fluorescence in solid state. The N-alkylation of imidazole subunit(s) in 1 using n-propyl iodide generated unsymmetrically or symmetrically alkylated thiazolothiazolebridged imidazolium salts with good water solubility and remarkably strong emission in solution. Furthermore, the replacement of iodide counter-anion by triflate or bis(trifluoromethane sulfonyl)imide achieved remarkably strong emission in solid state and in solution as well as good water solubility. The strong fluorescence of dicationic salts with triflate and NTf_(2)^(-)counter-anions in solid state can be ascribed to their twisted and rigid structures induced by interionic C-H···F hydrogen bonding.
基金supported by the grants from the National Natural Science Foundation of China(No.3180030530)the Fundamental Research Funds for the Central Universities(2572019BA14)
文摘To understand the function of phosphoenolpyruvate carboxylase kinase,we introduced PtPEPCK1 gene under the control of 35S promoter into 84K poplar(Populus alba×P.glandulosa).PtPEPCK1 gene is well-known for its role in gluconeogenesis.However,our data confi rmed that it has signifi cant eff ects on amino acid biosynthesis and nitrogen metabolism.Immunohistochemistry and fl uorescence microscopy indicate that PtPEPCK1 is specifi cally expressed in the cytoplasm of the spongy and palisade tissues.Overexpression of PtPEPCK1 was characterized through transcriptomics and metabolomics.The metabolites concentration of the ornithine cycle and its precursors also increased,of which N-acetylornithine was up-regulated almost 50-fold and ornithine 33.7-fold.These were accompanied by a massive increase in levels of several amino acids.Therefore,overexpression of PtPEPCK1 increases amino acid levels with urea cycle disorder.
基金funded by National Key Research and Development Program of China(No.2016YFC0503603)。
文摘Ginseng planting in Northeast China brings economic benefits but affects forest landscape integrity and native ecological processes.In order to quantify the impacts of ginseng planting on the forest landscape,Fusong County in Jilin Province was selected as a study area.The number and distribution of ginseng fields over different time was quantified based on remote sensing and ground surveys.Grid analysis and multiple regression analysis were used to study the impacts of ginseng planting on the landscape.The results showed that altitudes and slopes of ginseng fields increased and became increasingly scattered and smaller closer to the Changbai Mountain Nature Reserve.Ginseng fields and abandoned fields increased total patches and total area of the local forested landscape,and shared edge lengths between ginseng fields and forests,resulting in continuous fragmentation of the landscape.Although the total area of existing and abandoned ginseng fields accounts for a small fraction of the total landscape,their negative impacts on ecosystem conservation is significant.The local government needs to rationally plan ginseng planting,scientifically implement the restoration of abandoned ginseng lands,and enhance awareness of ginseng farmers to environmental stewardship.Our study has important significance for maintaining the healthy and stable development of the local ginseng industry and for improving the quality of regional ecological environment.
文摘Correction to:J.For.Res.https://doi.org/10.1007/s11676-019-01042-4 In the Original publication,the author has found that C1 and C4 in Fig.3 have been published with errors.The corrected Fig.3 C1 and C4 are provided below.
文摘The theoretical relationship between water injection multiple(i.e.injected pore volume)and water saturation is inferred from theoretical concepts of reservoir engineering.A mathematical model based on core displacement tests is established for the entire injection process that satisfies both initial displacement and extreme displacement,simultaneously.The results show that prior to the flooding,the water injection multiple has a linear relationship with the water saturation,and the utilization rate of the injected water is the highest.As water breakthrough at the production end,the water-cut increases,and the injection multiple increases exponentially while the utilization efficiency of the injected water gradually decreases.When the injection multiple approaches infinity,the utilization efficiency of the injected water gradually decreases to 0,by which time the water-cut at the production end is always 1.At this time,the water saturation no longer changes,and the water flooding recovery rate reaches its limit.Based on the experimental test data,a mathematical model of the entire process of injection multiple and water saturation is established,which has high fitting accuracy that can predict the injection multiple in the different stages of development of a mature oil reservoir.The dynamically changing index of the injection water utilization efficiency in reservoir development by reactive water flooding can be obtained through reasonable transformation of the mathematical model.This is of great significance in guiding evaluations of the effects of reservoir development and formulating countermeasures.
基金financially supported by the National Natural Science Foundation of China (22209039)Top-notch Personnel Fund of Henan Agricultural University (30500682)。
文摘Improving the complete ethanol electrooxidation on Pd-based catalysts in alkaline media has drawn widely attention due to the high mass energy density.However,the weak adsorption energy of CH_(3)CO^(*) on Pd restricts the C–C bond cleavage.Inspired by the molecular orbital theory,we proposed the d-state-editing strategy to construct more unoccupied d-states of Pd for the enhanced interaction with CH_(3)CO^(*) to break C–C bonds.As expected,the reduced number of e_g electrons and more unoccupied d-states of Pd successfully formed on as-prepared porous Rh Au–Pd Cu nanosheets(PNSs).Theoretical calculations show that the optimized d-states of Rh Au–Pd Cu PNS can effectively improve the adsorption of CH_(3)CO^(*) and drastically reduce the energy barrier of C–C bond cleavage,thus boosting the complete oxidation of ethanol.The charge ratio of C_1 pathway on Rh Au–Pd Cu PNSs is 51.5%,more than 2 times higher than that of Pd NSs.Our finding provides an innovative perspective for the design of highly-efficient noble-based electrocatalysts.
基金supported by the Topnotch Talents Program of Henan Agricultural University(30501032)the National Natural Science Foundation of China(52003228 and 52273197)+2 种基金the Science,Technology and Innovation Commission of Shenzhen Municipality(JCYJ2021324134613038)the Shenzhen Key Laboratory of Functional Aggregate Materials(ZDSYS20211021111400001)Shenzhen Peacock Team Project(KQTD20210811090142053).
文摘A new class of near-infrared(NIR)fluorescent organoboron AIEgens was successfully developed for latent fingerprints(LFPs)imaging.They exhibit real-time and in situ high-resolution imaging performance at 1-3 levels of LFPs by spraying method.In addition,we systematically elucidate the fingerprint imaging mechanism of these AIEgens.Significantly,the excellent level 3 structural imaging capabilities enable the application of them for analyzing incomplete LFPs and identifying individuals in different scenarios.
基金National Key Research and Development Program of China(2017YFA0207002)the National Natural Science Foundation of China(21906052,U2067215)Beijing Outstanding Young Scientist Program.
文摘Biochar shows significant potential to serve as a globally applicable material to remediate water and soil owing to the extensive availability of feedstocks and conducive physio-chemical surface characteristics.This review aims to highlight biochar production technologies,characteristics of biochar,and the latest advancements in immobilizing and eliminating heavy metal ions and organic pollutants in soil and water.Pyrolysis temperature,heat transfer rate,residence time,and type of feedstock are critical influential parameters.Biochar’s efficacy in managing contaminants relies on the pore size distribution,surface groups,and ion-exchange capacity.The molecular composition and physical architecture of biochar may be crucial when practically applied to water and soil.In general,biochar produced at relatively high pyrolysis temperatures can effectively manage organic pollutants via increasing surface area,hydrophobicity and microporosity.Biochar generated at lower temperatures is deemed to be more suitable for removing polar organic and inorganic pollutants through oxygen-containing functional groups,precipitation and electrostatic attraction.This review also presents the existing obstacles and future research direction related to biochar-based materials in immobilizing organic contaminants and heavy metal ions in effluents and soil.
基金Acknowledgements We thank the National Basic Research Program of China (973 Program, Grant No. 2013CB934400), the National Natural Science Foundation of China (Grant Nos. 21174097, 81272106 and 81271412), and the NIH (R01 DE017207). We also thank the PriorityAcademic Program Development of Jiangsu Higher Education Institutions (PAPD), the Excellent Youth Foundation of Jiangsu Province (BK2012009), International S&T Cooperation Project of the Ministry of S&T of China (2010DFR30850), the Key Natural Science Foundation of the Jiangsu Higher Education Institutions of China (11KGA430002) and Jiangsu Provincial Special Program of Medical Science (BL2012004) for support of this work.
文摘Silk materials with different nanostructures have been developed without the understanding of the inherent transformation mechanism. Here we attempt to reveal the conversion road of the various nanostructures and determine the critical regulating factors. The regulating conversion processes influenced by a hierarchical charge distribution were investigated, showing different transformations between molecules, nanoparticles and nanofibers. Various repulsion and compressive forces existed among silk fibroin molecules and aggregates due to the exterior and interior distribution of charge, which further controlled their aggregating and deaggregating behaviors and finally formed nanofibers with different sizes. Synergistic action derived from molecular mobility and concentrations could also tune the assembly process and final nanostructures, it is suggested that the complicated silk fibroin assembly processes comply a same rule based on charge distribution, offering a promising way to develop silk-based materials with designed nanostructures.
基金supported by the National Natural Science Foundation of China (81520108015)。
文摘Dear Editor,Approximately 500 million individuals suffer from hearing loss worldwide. The number of hearing-impaired individuals is estimated to increase to 900 million by 2050. The etiology of hearing loss is complex.