Electrolytic manganese metal residue(EMMR)harmless treatment has always lacked a low-cost and quick processing technology.In this study,surfactants,namely tetradecyl trimethylammonium chloride(TTC),sodium dodecyl benz...Electrolytic manganese metal residue(EMMR)harmless treatment has always lacked a low-cost and quick processing technology.In this study,surfactants,namely tetradecyl trimethylammonium chloride(TTC),sodium dodecyl benzene sulfonate(SDBS),sodium lignin sulfonate(SLS),and octadecyl trimethylammonium chloride(OTC),were used in the solidification of Mn^(2+)and removal of NH_(4)^(+)-N from EMMR.The Mn^(2+)and NH_(4)^(+)-N concentrations under different reaction conditions,Mn^(2+)solidification and NH_(4)^(+)-N removal mechanisms,and leaching behavior were studied.The results revealed that the surfactants could enhance the Mn^(2+)solidification and NH_(4)^(+)-N removal from EMMR,and the order of enhancement was as follows:TTC>SDBS>OTC>SLS.The NH_(4)^(+)-N and Mn^(2+)concentrations were 12.3 and 0.05 mg·L^(-1)with the use of 60.0 mg·kg^(-1)TTC under optimum conditions(solid–liquid ratio of 1.5:1,EMMR to BRM mass ratio of 100:8,temperature of 20℃,and reaction duration of 12 h),which met the integrated wastewater discharge standard(GB8978-1996).Mn^(2+)was mainly solidified as Mn(OH)_(2),MnOOH and MnSiO_(3),and NH_(4)^(+)-N in EMMR was mostly removed in the form of ammonia.The results of this study could provide a new idea for cost-effective EMMR harmless treatment.展开更多
Effective and mild activation of O_(2) is essential but challenging for aerobic oxidation. In heterogeneous catalysis, high-valence manganese oxide(e.g., +4) is known to be active for the oxidation, whereas divalent M...Effective and mild activation of O_(2) is essential but challenging for aerobic oxidation. In heterogeneous catalysis, high-valence manganese oxide(e.g., +4) is known to be active for the oxidation, whereas divalent MnO is ineffective due to its limited capacity to supply surface oxygen and its thermodynamically unstable structure when binding O_(2) in reaction conditions. Inspired by natural enzymes that rely on divalent Mn^(2+), we discovered that confining Mn^(2+) onto the Mn_(2)O_(3) surface through a dedicated calcination process creates highly active catalysts for the aerobic oxidation of 5-hydroxymethylfurfural, benzyl alcohol, and CO.The Mn_(2)O_(3)-confined Mn^(2+) is undercoordinated and efficiently mediates O_(2) activation, resulting in 2–3 orders of magnitude higher activity than Mn_(2)O_(3) alone. Through low-temperature infrared spectroscopy, we distinguished low-content Mn^(2+) sites at Mn_(2)O_(3) surface, which are difficult to be differentiated by X-ray photoelectron spectroscopy. The combination of in-situ energydispersive X-ray absorption spectroscopy and X-ray diffraction further provides insights into the formation of the newly identified active Mn^(2+) sites. By optimizing the calcination step, we were able to increase the catalytic activity threefold further.The finding offers promising frontiers for exploring active oxidation catalysts by utilizing the confinement of Mn^(2+)and oftenignored calcination skills.展开更多
Aluminum-containing adjuvants have been used for nearly 100 years to enhance immune responses in billions of doses of vaccines.To date,only a few adjuvants have been approved for use in humans,among which aluminum-con...Aluminum-containing adjuvants have been used for nearly 100 years to enhance immune responses in billions of doses of vaccines.To date,only a few adjuvants have been approved for use in humans,among which aluminum-containing adjuvants are the only ones widely used.However,the medical need for potent and safe adjuvants is currently continuously increasing,especially those triggering cellular immune responses for cytotoxic T lymphocyte activation,which are urgently needed for the development of efficient virus and cancer vaccines.Manganese is an essential micronutrient required for diverse biological activities,but its functions in immunity remain undefined.We previously reported that Mn^(2+) is important in the host defense against cytosolic dsDNA by facilitating cGAS-STING activation and that Mn^(2+)alone directly activates cGAS independent of dsDNA,leading to an unconventional catalytic synthesis of 2′3′-cGAMP.Herein,we found that Mn^(2+) strongly promoted immune responses by facilitating antigen uptake,presentation,and germinal center formation via both cGAS-STING and NLRP3 activation.Accordingly,a colloidal manganese salt(Mn jelly,MnJ)was formulated to act not only as an immune potentiator but also as a delivery system to stimulate humoral and cellular immune responses,inducing antibody production and CD4^(+)/CD8^(+)T-cell proliferation and activation by either intramuscular or intranasal immunization.When administered intranasally,MnJ also worked as a mucosal adjuvant,inducing high levels of secretory IgA.MnJ showed good adjuvant effects for all tested antigens,including T cell-dependent and T cell-independent antigens,such as bacterial capsular polysaccharides,thus indicating that it is a promising adjuvant candidate.展开更多
基金supported by National Natural Science Foundation of China(52174386,21806132)the National Key Research and Development Program of China(2018YFC1903500)+1 种基金the Science and Technology Plan Project of Sichuan Province(2021YFH0058)the Key Research and Development Program of Guangxi Province(AB18126088)。
文摘Electrolytic manganese metal residue(EMMR)harmless treatment has always lacked a low-cost and quick processing technology.In this study,surfactants,namely tetradecyl trimethylammonium chloride(TTC),sodium dodecyl benzene sulfonate(SDBS),sodium lignin sulfonate(SLS),and octadecyl trimethylammonium chloride(OTC),were used in the solidification of Mn^(2+)and removal of NH_(4)^(+)-N from EMMR.The Mn^(2+)and NH_(4)^(+)-N concentrations under different reaction conditions,Mn^(2+)solidification and NH_(4)^(+)-N removal mechanisms,and leaching behavior were studied.The results revealed that the surfactants could enhance the Mn^(2+)solidification and NH_(4)^(+)-N removal from EMMR,and the order of enhancement was as follows:TTC>SDBS>OTC>SLS.The NH_(4)^(+)-N and Mn^(2+)concentrations were 12.3 and 0.05 mg·L^(-1)with the use of 60.0 mg·kg^(-1)TTC under optimum conditions(solid–liquid ratio of 1.5:1,EMMR to BRM mass ratio of 100:8,temperature of 20℃,and reaction duration of 12 h),which met the integrated wastewater discharge standard(GB8978-1996).Mn^(2+)was mainly solidified as Mn(OH)_(2),MnOOH and MnSiO_(3),and NH_(4)^(+)-N in EMMR was mostly removed in the form of ammonia.The results of this study could provide a new idea for cost-effective EMMR harmless treatment.
基金supported by the Ministry of Science and Technology of China (2022YFA1503804)National Natural Science Foundation of China (22272031, 22102033)+1 种基金Science&Technology Commission of Shanghai Municipality (22ZR1408000, 22QA1401300)the Fundamental Research Funds for the Central Universities (20720220008)。
文摘Effective and mild activation of O_(2) is essential but challenging for aerobic oxidation. In heterogeneous catalysis, high-valence manganese oxide(e.g., +4) is known to be active for the oxidation, whereas divalent MnO is ineffective due to its limited capacity to supply surface oxygen and its thermodynamically unstable structure when binding O_(2) in reaction conditions. Inspired by natural enzymes that rely on divalent Mn^(2+), we discovered that confining Mn^(2+) onto the Mn_(2)O_(3) surface through a dedicated calcination process creates highly active catalysts for the aerobic oxidation of 5-hydroxymethylfurfural, benzyl alcohol, and CO.The Mn_(2)O_(3)-confined Mn^(2+) is undercoordinated and efficiently mediates O_(2) activation, resulting in 2–3 orders of magnitude higher activity than Mn_(2)O_(3) alone. Through low-temperature infrared spectroscopy, we distinguished low-content Mn^(2+) sites at Mn_(2)O_(3) surface, which are difficult to be differentiated by X-ray photoelectron spectroscopy. The combination of in-situ energydispersive X-ray absorption spectroscopy and X-ray diffraction further provides insights into the formation of the newly identified active Mn^(2+) sites. By optimizing the calcination step, we were able to increase the catalytic activity threefold further.The finding offers promising frontiers for exploring active oxidation catalysts by utilizing the confinement of Mn^(2+)and oftenignored calcination skills.
基金supported by the National Natural Science Foundation of China(31830022 and 81621001)the Chinese Ministry of Science and Technology(2019YFA0508500).
文摘Aluminum-containing adjuvants have been used for nearly 100 years to enhance immune responses in billions of doses of vaccines.To date,only a few adjuvants have been approved for use in humans,among which aluminum-containing adjuvants are the only ones widely used.However,the medical need for potent and safe adjuvants is currently continuously increasing,especially those triggering cellular immune responses for cytotoxic T lymphocyte activation,which are urgently needed for the development of efficient virus and cancer vaccines.Manganese is an essential micronutrient required for diverse biological activities,but its functions in immunity remain undefined.We previously reported that Mn^(2+) is important in the host defense against cytosolic dsDNA by facilitating cGAS-STING activation and that Mn^(2+)alone directly activates cGAS independent of dsDNA,leading to an unconventional catalytic synthesis of 2′3′-cGAMP.Herein,we found that Mn^(2+) strongly promoted immune responses by facilitating antigen uptake,presentation,and germinal center formation via both cGAS-STING and NLRP3 activation.Accordingly,a colloidal manganese salt(Mn jelly,MnJ)was formulated to act not only as an immune potentiator but also as a delivery system to stimulate humoral and cellular immune responses,inducing antibody production and CD4^(+)/CD8^(+)T-cell proliferation and activation by either intramuscular or intranasal immunization.When administered intranasally,MnJ also worked as a mucosal adjuvant,inducing high levels of secretory IgA.MnJ showed good adjuvant effects for all tested antigens,including T cell-dependent and T cell-independent antigens,such as bacterial capsular polysaccharides,thus indicating that it is a promising adjuvant candidate.
