Biomineralization has garnered significant attention in the field of wastewater treatment due to its notable cost reduction compared to conventional methods.The reinjection water from oilfields containing an exceeding...Biomineralization has garnered significant attention in the field of wastewater treatment due to its notable cost reduction compared to conventional methods.The reinjection water from oilfields containing an exceedingly high concentration of calcium and ferric ions will pose amajor hazard in production.However,the utilization of biomineralization for precipitating these ions has been scarcely investigated due to limited tolerance among halophiles towards such extreme conditions.In this study,free and immobilized halophiles Virgibacillus dokdonensis were used to precipitate these ions and the effects were compared,at the same time,biomineralizationmechanisms and mineral characteristicswere further explored.The results showthat bacterial concentration and carbonic anhydrase activitywere higher when additionally adding ferric ion based on calcium ion;the content of protein,polysaccharides,deoxyribonucleic acid and humic substances in the extracellular polymers also increased compared to control.Calcium ions were biomineralized into calcite and vaterite with mul-tiple morphology.Due to iron doping,the crystallinity and thermal stability of calcium carbonate decreased,the content of O-C=O,N-C=OandC-O-PO_(3) increased,the stable carbon isotope values became much more negative,andβ-sheet in minerals disappeared.Higher calcium concentrations facilitated ferric ion precipitation,while ferric ions hindered calcium precipitation.The immobilized bacteria performed better in ferric ion removal,with a precipitation ratio exceeding 90%.Free bacteria performed better in calcium removal,and the precipitation ratio reached a maximum of 56%.This research maybe provides some reference for the co-removal of calcium and ferric ions from the oilfield wastewater.展开更多
Biomineralization has become a research focus in wastewater treatment due to its much lower costs compared to traditional methods.However,the low sodium chloride(NaCl)-tolerance of bacteria limits applications to only...Biomineralization has become a research focus in wastewater treatment due to its much lower costs compared to traditional methods.However,the low sodium chloride(NaCl)-tolerance of bacteria limits applications to only water with low NaCl concentrations.Here,calcium ions in hypersaline wastewater(10%NaCl)were precipitated by free and immobilized Halovibrio mesolongii HMY2 bacteria and the differences between them were determined.The results show that calcium ions can be transformed into several types of calcium carbonate with a range of morphologies,abundant organic functional groups(C-H,C-O-C,C=O,etc),protein secondary structures(β-sheet,α-helix,3_(10)helix,andβ-turn),P=O and S-H indicated by P2p and S2p,and more negativeδ^(13)C_(PDB)(‰)values(-16.8‰to-18.4‰).The optimal conditions for the immobilized bacteria were determined by doing experiments with six factors and five levels and using response surface method.Under the action of two groups of immobilized bacteria prepared under the optimal conditions,by the 10^(th)day,Ca^(2+)ion precipitation ratios had increased to 79%-89%and 80%-88%with changes in magnesium ion cencentrations.Magnesium ions can significantly inhibit the calcium ion precipitation,and this inhibitory effect can be decreased under the action of immobilized bacteria.Minerals induced by immobilized bacteria always aggregated together,had higher contents of Mg,P,and S,lower stable carbon isotope values and less well-developed protein secondary structures.This study demonstrates an economic and eco-friendly method for recycling calcium ions in hypersaline wastewater,providing an easy step in the process of desalination.展开更多
Globally elevated temperatures during the Cretaceous extreme greenhouse climate interval were punctuated by the Valanginian cooling event,which was characterized by a positive carbon isotope excursion,global cooling,a...Globally elevated temperatures during the Cretaceous extreme greenhouse climate interval were punctuated by the Valanginian cooling event,which was characterized by a positive carbon isotope excursion,global cooling,and a glacial event approximately at 135 Ma.Disentangling ocean temperature and continental ice volume trends enables us to better understand climate fluctuations over deep time.We investigated the ocean temperature-ice sheet dynamics of glaciation events that occurred in the Cretaceous greenhouse world.New clumped isotope andδ^(18) O data from sites in the Tethyan Ocean show that seawater temperatures decreased by 5-6°C,consistent with the development of glacial periods,and maximum ice volumes about half the size of present-day Antarctica.This cooling event provides a counter-example to other Mesozoic climate transitions driven by changes in atmospheric greenhouse gas contents.Our results emphasize the importance of quantitatively reconstructing continental ice volume,providing further support for exploring deep-time Earth climate dynamics.展开更多
基金supported by the National Natural Science Foundation of China(Nos.42072136,41972108,and 42106144)the Natural Science Foundation of Shandong Province(Nos.ZR2023MD063,ZR2020MC041,and ZR2020QD089)+1 种基金the Key Laboratory of Marine Biogenetic Resources,Third Institute of Oceanography,Ministry of Natural Resources(No.SKDZK20230127)the Foreign visiting scholar funded by Shandong Provincial government.
文摘Biomineralization has garnered significant attention in the field of wastewater treatment due to its notable cost reduction compared to conventional methods.The reinjection water from oilfields containing an exceedingly high concentration of calcium and ferric ions will pose amajor hazard in production.However,the utilization of biomineralization for precipitating these ions has been scarcely investigated due to limited tolerance among halophiles towards such extreme conditions.In this study,free and immobilized halophiles Virgibacillus dokdonensis were used to precipitate these ions and the effects were compared,at the same time,biomineralizationmechanisms and mineral characteristicswere further explored.The results showthat bacterial concentration and carbonic anhydrase activitywere higher when additionally adding ferric ion based on calcium ion;the content of protein,polysaccharides,deoxyribonucleic acid and humic substances in the extracellular polymers also increased compared to control.Calcium ions were biomineralized into calcite and vaterite with mul-tiple morphology.Due to iron doping,the crystallinity and thermal stability of calcium carbonate decreased,the content of O-C=O,N-C=OandC-O-PO_(3) increased,the stable carbon isotope values became much more negative,andβ-sheet in minerals disappeared.Higher calcium concentrations facilitated ferric ion precipitation,while ferric ions hindered calcium precipitation.The immobilized bacteria performed better in ferric ion removal,with a precipitation ratio exceeding 90%.Free bacteria performed better in calcium removal,and the precipitation ratio reached a maximum of 56%.This research maybe provides some reference for the co-removal of calcium and ferric ions from the oilfield wastewater.
基金supported by the National Natural Science Foundation of China(Nos.41772095,42072136,41972108,42106144)the Natural Science Foundation of Shandong Province(Nos.ZR2019MD027,ZR2020QD089,ZR2021QE125)+4 种基金SDUST Research Fund(No.2015TDJH101)Scientific and Technological Innovation Project Financially Supported by Qingdao National Laboratory for Marine Science and Technology(No.2016ASKJ13)Major Innovation Projects of Key R&D Program of Shandong Province(No.2019JZZY020808)the Foundation of SINOPEC(No.P20059-7)Innovation and Entrepreneurship Training program for College students(Nos.202110424157,202110424158)。
文摘Biomineralization has become a research focus in wastewater treatment due to its much lower costs compared to traditional methods.However,the low sodium chloride(NaCl)-tolerance of bacteria limits applications to only water with low NaCl concentrations.Here,calcium ions in hypersaline wastewater(10%NaCl)were precipitated by free and immobilized Halovibrio mesolongii HMY2 bacteria and the differences between them were determined.The results show that calcium ions can be transformed into several types of calcium carbonate with a range of morphologies,abundant organic functional groups(C-H,C-O-C,C=O,etc),protein secondary structures(β-sheet,α-helix,3_(10)helix,andβ-turn),P=O and S-H indicated by P2p and S2p,and more negativeδ^(13)C_(PDB)(‰)values(-16.8‰to-18.4‰).The optimal conditions for the immobilized bacteria were determined by doing experiments with six factors and five levels and using response surface method.Under the action of two groups of immobilized bacteria prepared under the optimal conditions,by the 10^(th)day,Ca^(2+)ion precipitation ratios had increased to 79%-89%and 80%-88%with changes in magnesium ion cencentrations.Magnesium ions can significantly inhibit the calcium ion precipitation,and this inhibitory effect can be decreased under the action of immobilized bacteria.Minerals induced by immobilized bacteria always aggregated together,had higher contents of Mg,P,and S,lower stable carbon isotope values and less well-developed protein secondary structures.This study demonstrates an economic and eco-friendly method for recycling calcium ions in hypersaline wastewater,providing an easy step in the process of desalination.
基金supported by the National Natural Science Foundation of China BSCTPES project(41988101)Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0708)+1 种基金the National Natural Science Foundation of China(42102021),the Chinese Academy of Sciences,Strategic Priority Research Program(XDA20070301)the Special Research Assistant Funding Project of Chinese Academy of Sciences(2021000015).
文摘Globally elevated temperatures during the Cretaceous extreme greenhouse climate interval were punctuated by the Valanginian cooling event,which was characterized by a positive carbon isotope excursion,global cooling,and a glacial event approximately at 135 Ma.Disentangling ocean temperature and continental ice volume trends enables us to better understand climate fluctuations over deep time.We investigated the ocean temperature-ice sheet dynamics of glaciation events that occurred in the Cretaceous greenhouse world.New clumped isotope andδ^(18) O data from sites in the Tethyan Ocean show that seawater temperatures decreased by 5-6°C,consistent with the development of glacial periods,and maximum ice volumes about half the size of present-day Antarctica.This cooling event provides a counter-example to other Mesozoic climate transitions driven by changes in atmospheric greenhouse gas contents.Our results emphasize the importance of quantitatively reconstructing continental ice volume,providing further support for exploring deep-time Earth climate dynamics.
