Laminarin oligosaccharides(LOSs)with a specific degree of polymerization prepared through the laminarin degradation via laminarinase present more significant nutritional functions and application values.Human intestin...Laminarin oligosaccharides(LOSs)with a specific degree of polymerization prepared through the laminarin degradation via laminarinase present more significant nutritional functions and application values.Human intestinal bacteria are promising potential producers of novel carbohydrate-active enzymes with unique properties.Here,a novel glycoside hydrolase family 128(GH128)laminarinase OUC-BsLam26 from the intestinal bacterium Bacteroides sp.CBA7301 was heterologously expressed and characterized.The recombinant OUC-BsLam26 with a molecular mass of 49.86 kDa exhibits highest activity(6.60 U/mg)at 45℃ and pH 6.0,which shows noticeable temperature and pH stability.The purified OUC-BsLam26 could degrade laminarin via an endo-type mode with the generation of laminaripentaose,laminaritetraose,laminaritriose,and laminaribiose,among them,laminaritetraose is the principal product,which accounts for 45.25% of the total products,which is significantly different from the reported GH128 laminarinases.The minimum recognition substrate of OUC-BsLam26 is laminarihexaose.Furthermore,OUC-BsLam26 also could catalyze the transglycosylation process with the production of some novel glycosides.Altogether,the intestinal bacterium Bacteroides sp.CBA7301 contains laminarinase with unique product composition and OUC-BsLam26 is a hopeful bio-catalyst with the potential to produce laminaritetraose and some novel glycosides.展开更多
Membrane desalination is an economical and energy-efficient method to meet the current worldwide water scarcity.However,state-of-the-art reverse osmosis membranes are gradually being replaced by novel membrane materia...Membrane desalination is an economical and energy-efficient method to meet the current worldwide water scarcity.However,state-of-the-art reverse osmosis membranes are gradually being replaced by novel membrane materials as a result of ongoing technological advancements.These novel materials possess intrinsic pore structures or can be assembled to form lamellar membrane channels for selective transport of water or solutes(e.g.,NaCl).Still,in real applications,the results fall below the theoretical predictions,and a few properties,including large-scale fabrication,mechanical strength,and chemical stability,also have an impact on the overall effectiveness of those materials.In view of this,we develop a new evaluation framework in the form of radar charts with five dimensions(i.e.,water permeance,water/NaCl selectivity,membrane cost,scale of development,and stability)to assess the advantages,disadvantages,and potential of state-of-the-art and newly developed desalination membranes.In this framework,the reported thin film nanocomposite membranes and membranes developed from novel materials were compared with the state-of-the-art thin film composite membranes.This review will demonstrate the current advancements in novel membrane materials and bridge the gap between different desalination membranes.In this review,we also point out the prospects and challenges of next-generation membranes for desalination applications.We believe that this comprehensive framework may be used as a future reference for designing next-generation desalination membranes and will encourage further research and development in the field of membrane technology,leading to new insights and advancements.展开更多
Effectively separating bastnaesite from calcium-bearing gangue minerals(particularly calcite)presents a formidable challenge,making the development of efficient collectors crucial.To achieve this,we have designed and ...Effectively separating bastnaesite from calcium-bearing gangue minerals(particularly calcite)presents a formidable challenge,making the development of efficient collectors crucial.To achieve this,we have designed and synthesized a novel,highly efficient,water-soluble cationic collector,N-dodecylisopropanolamine(NDIA),for use in the bastnaesite-calcite flotation process.Density functional theory(DFT)calculations identified the amine nitrogen atom in NDIA as the site most susceptible to electrophilic attack and electron loss.By introducing an OH group into the traditional collector dodecylamine(DDA)structure,NDIA provided additional adsorption sites,enabling synergistic adsorption on the surface of bastnaesite,thereby significantly enhancing both the floatability and selectivity of these minerals.The recovery of bastnaesite was 76.02%,while the calcite was 1.26%.The NDIA markedly affected the zeta potential of bastnaesite,while its impact on calcite was relatively minor.Detailed Fourier-transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS)results elucidated that the―NH―and―OH groups in NDIA anchored onto the bastnaesite surface through robust electrostatic and hydrogen bonding interactions,thereby enhancing bastnaesite's affinity for NDIA.Furthermore,in situ atomic force microscopy(AFM)provided conclusive evidence of NDIA aggregation on the bastnaesite surface,improving contact angle and hydrophobicity,and significantly boosting the flotation recovery of bastnaesite.展开更多
A novel small molecule depressant(M-DEP)was used to separate chalcopyrite and molybdenite via flotation.The results showed that M-DEP had an excellent selective depression on molybdenite,while had little effect on the...A novel small molecule depressant(M-DEP)was used to separate chalcopyrite and molybdenite via flotation.The results showed that M-DEP had an excellent selective depression on molybdenite,while had little effect on the flotation of chalcopyrite.The adsorption capacity of M-DEP on the surface of molybdenite was greater than that on chalcopyrite surface.The adsorption of M-DEP reduced the floatability of molybdenite and had less effect on the floatability of chalcopyrite,which was due to its different adsorption modes on the surface of the two minerals.Furthermore,the interaction between chalcopyrite and M-DEP was mainly chemical interaction,and almost all of the adsorbed M-DEP molecules were removed and replaced by sodium butyl xanthate(SBX).By contrast,hydrophobic interaction was the main way in which M-DEP was adsorbed on the molybdenite surface with little chemical interaction,which was less interfered by SBX addition.Therefore,M-DEP had a super selective depression on molybdenite.The study provided a novel depressant and approach for the deep separation of chalcopyrite and molybdenite via flotation.展开更多
Addressing the ongoing challenge of enhancing propulsion efficiency in rim-driven thrusters(RDTs),a novel energy-saving appendage was designed to mitigate energy dissipation and improve efficiency.Computational fluid ...Addressing the ongoing challenge of enhancing propulsion efficiency in rim-driven thrusters(RDTs),a novel energy-saving appendage was designed to mitigate energy dissipation and improve efficiency.Computational fluid dynamics was utilized to examine the disparities in openwater performance between RDTs with and without this appendage.The Reynolds-Averaged Navier–Stokes equations were solved using the Moving Reference Frame approach within the established STAR-CCM+software.The accuracy of these methodologies was confirmed through a comparison of numerical simulations with experimental data.A meticulous analysis evaluated the alterations in propulsion efficiency of RDTs pre-and post-appendage integration across various advance coefficients.Additionally,a comprehensive assessment of thrust and torque coefficient distributions facilitated a comprehensive understanding of the appendage’s energy-saving potential.Results demonstrated that the new appendage diminishes the diffusive wake behind the rotor disk,fostering a more uniform flow distribution.A notable reduction in the lowpressure zone on the rotor blade’s thrust side was observed,accompanied by an elevation in the high-pressure area.This generated a distinct pressure disparity between the blade’s thrust and suction sides,mitigating the low-pressure region at the blade tip and reducing the likelihood of cavitation.The manuscript further elucidates the rationale behind these alterations,providing detailed insights into flow field dynamics.展开更多
基金supported by the National Natural Science Foundation of China(32072159)Natural Science Foundation of Hainan Province(322QN338)+4 种基金Young Talent of Lifting Engineering for Science and Technology in Shandong,China(SDAST2021qt18)Qingdao Science and Technology Plan Key Research and Development Project(22-3-3-hygg-28-hy)Fundamental Research Funds for the Central Universities(202262003)Taishan Scholar Project of Shandong Province(tsqn202312099)Support Program for Youth Innovation Technology in Colleges and Universities of Shandong Province(2023KJ041)。
文摘Laminarin oligosaccharides(LOSs)with a specific degree of polymerization prepared through the laminarin degradation via laminarinase present more significant nutritional functions and application values.Human intestinal bacteria are promising potential producers of novel carbohydrate-active enzymes with unique properties.Here,a novel glycoside hydrolase family 128(GH128)laminarinase OUC-BsLam26 from the intestinal bacterium Bacteroides sp.CBA7301 was heterologously expressed and characterized.The recombinant OUC-BsLam26 with a molecular mass of 49.86 kDa exhibits highest activity(6.60 U/mg)at 45℃ and pH 6.0,which shows noticeable temperature and pH stability.The purified OUC-BsLam26 could degrade laminarin via an endo-type mode with the generation of laminaripentaose,laminaritetraose,laminaritriose,and laminaribiose,among them,laminaritetraose is the principal product,which accounts for 45.25% of the total products,which is significantly different from the reported GH128 laminarinases.The minimum recognition substrate of OUC-BsLam26 is laminarihexaose.Furthermore,OUC-BsLam26 also could catalyze the transglycosylation process with the production of some novel glycosides.Altogether,the intestinal bacterium Bacteroides sp.CBA7301 contains laminarinase with unique product composition and OUC-BsLam26 is a hopeful bio-catalyst with the potential to produce laminaritetraose and some novel glycosides.
基金supported by a grant from the Research Grants Council of the Hong Kong Special Administration Region,China(SRFS2021-7S04)Partial support was also received from the Seed Funding for Strategic Interdisciplinary Research Scheme(102010174)+1 种基金Seed Fund for Basic Research(202111159075)of The University of Hong KongIn addition,part of this work was supported by the European Union’s Horizon 2020 research and innovation programme under grant agreement INTELWAT(No 958454).
文摘Membrane desalination is an economical and energy-efficient method to meet the current worldwide water scarcity.However,state-of-the-art reverse osmosis membranes are gradually being replaced by novel membrane materials as a result of ongoing technological advancements.These novel materials possess intrinsic pore structures or can be assembled to form lamellar membrane channels for selective transport of water or solutes(e.g.,NaCl).Still,in real applications,the results fall below the theoretical predictions,and a few properties,including large-scale fabrication,mechanical strength,and chemical stability,also have an impact on the overall effectiveness of those materials.In view of this,we develop a new evaluation framework in the form of radar charts with five dimensions(i.e.,water permeance,water/NaCl selectivity,membrane cost,scale of development,and stability)to assess the advantages,disadvantages,and potential of state-of-the-art and newly developed desalination membranes.In this framework,the reported thin film nanocomposite membranes and membranes developed from novel materials were compared with the state-of-the-art thin film composite membranes.This review will demonstrate the current advancements in novel membrane materials and bridge the gap between different desalination membranes.In this review,we also point out the prospects and challenges of next-generation membranes for desalination applications.We believe that this comprehensive framework may be used as a future reference for designing next-generation desalination membranes and will encourage further research and development in the field of membrane technology,leading to new insights and advancements.
基金supported by the the National Key R&D Program of China(No.2021YFC2900800)National Natural Science Foundation of China(Nos.52425406,51874247,51922091,and 52204285)+4 种基金the Open Research Fund of State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization(No.CNMRCUKF2001)Science and Technology Major Project of Ordos City-Iconic Innovation Team and “Rejuvenating Inner Mongolia through Science and Technology”(No.202204/2023)Yueqi Outstanding Scholar Award of CUMTB(No.202022)Funded by Open Foundation of State Key Laboratory of Mineral Processing(No.BGRIMM-KJSKL-2023-05)Fundamental Research Funds for the Central Universities(Ph.D.Top Innovative Talents Fund of CUMT BBJ2024048)。
文摘Effectively separating bastnaesite from calcium-bearing gangue minerals(particularly calcite)presents a formidable challenge,making the development of efficient collectors crucial.To achieve this,we have designed and synthesized a novel,highly efficient,water-soluble cationic collector,N-dodecylisopropanolamine(NDIA),for use in the bastnaesite-calcite flotation process.Density functional theory(DFT)calculations identified the amine nitrogen atom in NDIA as the site most susceptible to electrophilic attack and electron loss.By introducing an OH group into the traditional collector dodecylamine(DDA)structure,NDIA provided additional adsorption sites,enabling synergistic adsorption on the surface of bastnaesite,thereby significantly enhancing both the floatability and selectivity of these minerals.The recovery of bastnaesite was 76.02%,while the calcite was 1.26%.The NDIA markedly affected the zeta potential of bastnaesite,while its impact on calcite was relatively minor.Detailed Fourier-transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS)results elucidated that the―NH―and―OH groups in NDIA anchored onto the bastnaesite surface through robust electrostatic and hydrogen bonding interactions,thereby enhancing bastnaesite's affinity for NDIA.Furthermore,in situ atomic force microscopy(AFM)provided conclusive evidence of NDIA aggregation on the bastnaesite surface,improving contact angle and hydrophobicity,and significantly boosting the flotation recovery of bastnaesite.
基金support from the Project of Zhongyuan Critical Metals Laboratory(No.GJJSGFYQ202334)Natural Science Foundation of Henan Province(No.242300420002)+1 种基金National key research and development program(No.2020YFC1908804)National Natural Science Foundation of China(No.51804275).Moreover,we also thank Modern Analysis and Gene Sequencing Centre in Zhengzhou University.
文摘A novel small molecule depressant(M-DEP)was used to separate chalcopyrite and molybdenite via flotation.The results showed that M-DEP had an excellent selective depression on molybdenite,while had little effect on the flotation of chalcopyrite.The adsorption capacity of M-DEP on the surface of molybdenite was greater than that on chalcopyrite surface.The adsorption of M-DEP reduced the floatability of molybdenite and had less effect on the floatability of chalcopyrite,which was due to its different adsorption modes on the surface of the two minerals.Furthermore,the interaction between chalcopyrite and M-DEP was mainly chemical interaction,and almost all of the adsorbed M-DEP molecules were removed and replaced by sodium butyl xanthate(SBX).By contrast,hydrophobic interaction was the main way in which M-DEP was adsorbed on the molybdenite surface with little chemical interaction,which was less interfered by SBX addition.Therefore,M-DEP had a super selective depression on molybdenite.The study provided a novel depressant and approach for the deep separation of chalcopyrite and molybdenite via flotation.
文摘Addressing the ongoing challenge of enhancing propulsion efficiency in rim-driven thrusters(RDTs),a novel energy-saving appendage was designed to mitigate energy dissipation and improve efficiency.Computational fluid dynamics was utilized to examine the disparities in openwater performance between RDTs with and without this appendage.The Reynolds-Averaged Navier–Stokes equations were solved using the Moving Reference Frame approach within the established STAR-CCM+software.The accuracy of these methodologies was confirmed through a comparison of numerical simulations with experimental data.A meticulous analysis evaluated the alterations in propulsion efficiency of RDTs pre-and post-appendage integration across various advance coefficients.Additionally,a comprehensive assessment of thrust and torque coefficient distributions facilitated a comprehensive understanding of the appendage’s energy-saving potential.Results demonstrated that the new appendage diminishes the diffusive wake behind the rotor disk,fostering a more uniform flow distribution.A notable reduction in the lowpressure zone on the rotor blade’s thrust side was observed,accompanied by an elevation in the high-pressure area.This generated a distinct pressure disparity between the blade’s thrust and suction sides,mitigating the low-pressure region at the blade tip and reducing the likelihood of cavitation.The manuscript further elucidates the rationale behind these alterations,providing detailed insights into flow field dynamics.
