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The fate of carbon resulting from pore water exchange in a mangrove and Spartina alterniflora ecozone
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作者 Weizhen Jiang Guizhi Wang +4 位作者 Qing Li Manab Kumar Dutta Shilei Jin Guiyuan Dai Yi Xu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期61-76,共16页
Mangrove and salt-marsh wetlands are important coastal carbon sinks.In order to quantify carbon export via pore water exchange and to evaluate subsequent fate of the exported carbon,we carried out continuous observati... Mangrove and salt-marsh wetlands are important coastal carbon sinks.In order to quantify carbon export via pore water exchange and to evaluate subsequent fate of the exported carbon,we carried out continuous observations in a mangrove-Spartina alterniflora ecozone in the Zhangjiang River Estuary,China.The carbon fluxes via pore water exchange were estimated using^(222)Rn and^(228)Ra as tracers to be(2.15±0.63)mol/(m^(2)∙d)for dissolved inorganic carbon(DIC)and(-0.008±0.07)mol/(m^(2)∙d)for dissolved organic carbon(DOC)in the wet season and(3.02±0.65)mol/(m^(2)∙d)for DIC and(-0.15±0.007)mol/(m^(2)∙d)for DOC in the dry season in the mangrove-dominated creek(M-creek),while(2.52±0.82)mol/(m^(2)∙d)for DIC and(0.02±0.09)mol/(m^(2)∙d)for DOC in the dry season in the S.alterniflora-dominated creek(SA-creek).The negative value means that pore water was a sink of DOC in the creek.The total carbon via pore water exchange in the tidal creeks in the mangroves accounted for 41%-55%of the net carbon fixed by mangrove vegetation and was 3-4 times as much as the soil carbon accretion in the mangroves.The exported carbon in the form of DIC contributed all of the carbon outwelling from the M-creek and 79%of the carbon outwelling from the SA-creek,implying effective fixation of carbon by the wetland ecosystem.Moreover,it resulted in 54%in the dry season,75%in the wet season of the carbon dioxide released from the M-creek to the atmosphere,and 84%of the release from the SA-creek.Therefore,quantification of pore water exchange and related soil carbon loss is essential to trace the fate of carbon fixed in intertidal wetlands. 展开更多
关键词 MANGROVE SALT-MARSH carbon dioxide carbon accretion carbon outwelling pore water exchange
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Temporal Dynamics and Performance Association of the Tetrasphaera-Enriched Microbiome for Enhanced Biological Phosphorus Removal
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作者 Hui Wang Yubo Wang +2 位作者 Guoqing Zhang Ze Zhao Feng Ju 《Engineering》 SCIE EI CAS CSCD 2023年第10期168-178,共11页
Tetrasphaera have been recently identified based on the 16S ribosomal RNA(rRNA)gene as among the most abundant polyphosphate-accumulating organisms(PAOs)in global full-scale wastewater treatment plants(WWTPs)with enha... Tetrasphaera have been recently identified based on the 16S ribosomal RNA(rRNA)gene as among the most abundant polyphosphate-accumulating organisms(PAOs)in global full-scale wastewater treatment plants(WWTPs)with enhanced biological phosphorus removal(EBPR).However,it is unclear how Tetrasphaera PAOs are selectively enriched in the context of the EBPR microbiome.In this study,an EBPR microbiome enriched with Tetrasphaera(accounting for 40%of 16S sequences on day 113)was built using a top-down design approach featuring multicarbon sources and a low dosage of allylthiourea.The microbiome showed enhanced nutrient removal(phosphorus removal~85%and nitrogen removal~80%)and increased phosphorus recovery(up to 23.2 times)compared with the seeding activated sludge from a local full-scale WWTP.The supply of 1 mg·L^(-1)allylthiourea promoted the coselection of Tetrasphaera PAOs and Microlunatus PAOs and sharply reduced the relative abundance of both ammonia oxidizer Nitrosomonas and putative competitors Brevundimonas and Paracoccus,facilitating the establishment of the EBPR microbiome.Based on 16S rRNA gene analysis,a putative novel PAO species,EBPR-ASV0001,was identified with Tetrasphaera japonica as its closest relative.This study provides new knowledge on the establishment of a Tetrasphaera-enriched microbiome facilitated by allylthiourea,which can be further exploited to guide future process upgrading and optimization to achieve and/or enhance simultaneous biological phosphorus and nitrogen removal from high-strength wastewater. 展开更多
关键词 Enhanced biological phosphorus removal(EBPR) Polyphosphate-accumulating organisms(PAOs) Tetrasphaera MICROBIOME Phosphorus recovery
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Seasonal metal fluxes derived by the interaction of surface water and groundwater in an aquaculture estuary
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作者 Xiaoxiong Wang Jordi Garcia-Orellana +5 位作者 Xiaogang Chen Jianan Liu Fenfen Zhang Jianguo Qu Zhuoyi Zhu Jinzhou Du 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期113-124,共12页
Submarine groundwater discharge(SGD)plays a major role as a conveyor of metals to coastal waters.However,the seasonal change of metal fluxes derived through SGD is unclear.Here,we evaluated the behaviours and fluxes o... Submarine groundwater discharge(SGD)plays a major role as a conveyor of metals to coastal waters.However,the seasonal change of metal fluxes derived through SGD is unclear.Here,we evaluated the behaviours and fluxes of trace metals(Mn,Fe,Ba,Pb,U,Cr,Zn,Cu)in an estuary under different seasonal conditions.The behaviours of trace metals revealed that SGD was the source of Mn(3.51 mmol/(m^(2)·d)),Fe(0.174 mmol/(m^(2)·d))and Ba(0.024 mmol/(m^(2)·d)),but the Cu sink(−0.55μmol/(m^(2)·d))and other metals exhibited a seasonal source‒sink conversion.The seasonal variation of dissolved organic matter and the fresh groundwater proportion in subterranean estuaries may have an important effect on metals fluxes especially for the Fe,Mn and Ba.Our result shows that the single seasonal metal fluxes estimation applied to the annual scale will cause a large deviation,up to 3.6 times for Fe,5.5 times for Mn,and 15 times for Ba.Therefore,the influence of seasonal fluctuations on SGDderived metal fluxes cannot be ignored,and our findings will be important for comprehending the metal budget and cycle in nearshore environment. 展开更多
关键词 subterranean estuary seawater intrusion heavy metals seasonal changes coastal management
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Recycling of ironmaking and steelmaking slags in Japan and China 被引量:5
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作者 Hiroyuki Matsuura Xiao Yang +2 位作者 Guangqiang Li Zhangfu Yuan Fumitaka Tsukihashi 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第4期739-749,共11页
The mass production of steel is inevitably accompanied by large quantities of slags.The treatment of ironmaking and steelmaking slags is a great challenge in the sustainable development of the steel industry.Japan and... The mass production of steel is inevitably accompanied by large quantities of slags.The treatment of ironmaking and steelmaking slags is a great challenge in the sustainable development of the steel industry.Japan and China are two major steel producing countries that have placed a large emphasis on developing new technologies to decrease slag emission or promote slag valorization.Slags are almost completely reused or recycled in Japan.However,due to stagnant infrastructural investments,future applications of slags in conventional sectors are expected to be difficult.Exploring new functions or applications of slags has become a research priority in Japan.For example,the utilization of steelmaking slags in offshore seabeds to create marine forests is under development.China is the top steel producer in the world.The utilization ratios of ironmaking and steelmaking slags have risen steadily in recent years,driven largely by technological advances.For example,hot stage processing of slags for materials as well as heat recovery techniques has been widely applied in steel plants with good results.However,increasing the utilization ratio of basic oxygen furnace slags remains a major challenge.Technological innovations in slag recycling are crucial for the steel industries in Japan and China.Here,the current status and developing trends of utilization technologies of slags in both countries are reviewed. 展开更多
关键词 IRONMAKING STEELMAKING SLAG RECYCLING seawater STABILIZATION
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Linking bacterial and archaeal community dynamics to related hydrological,geochemical and environmental characteristics between surface water and groundwater in a karstic estuary
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作者 Xiaogang Chen Qi Ye +5 位作者 Jinzhou Du Neven Cukrov Nuša Cukrov Yan Zhang Ling Li Jing Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期158-170,共13页
Subterranean estuaries(STEs)are characterized by the mixing of terrestrial fresh groundwater and seawater in coastal aquifers.Although microorganisms are important components of coastal groundwater ecosystems and play... Subterranean estuaries(STEs)are characterized by the mixing of terrestrial fresh groundwater and seawater in coastal aquifers.Although microorganisms are important components of coastal groundwater ecosystems and play critical roles in biogeochemical transformations in STEs,limited information is available about how their community dynamics interact with hydrological,geochemical and environmental characteristics in STEs.Here,we studied bacterial and archaeal diversities and distributions with 16S rRNA-based Illumina MiSeq sequencing technology between surface water and groundwater in a karstic STE.Principal-coordinate analysis found that the bacterial and archaeal communities in the areas where algal blooms occurred were significantly separated from those in other stations without algal bloom occurrence.Canonical correspondence analysis showed that nutrients and salinity can explain the patterns of bacterial and archaeal community dynamics.The results suggest that hydrological,geochemical and environmental characteristics between surface water and groundwater likely control the bacterial and archaeal diversities and distributions in STEs.Furthermore,we found that some key species can utilize terrestrial pollutants such as nitrate and ammonia in STEs,indicating that these species(e.g.,Nitrosopumilus maritimus,Limnohabitans parvus and Simplicispira limi)may be excellent candidates for in situ degradation/remediation of coastal groundwater contaminations concerned with the nitrate and ammonia.Overall,this study reveals the coupling relationship between the microbial communities and hydrochemical environments in STEs,and provides a perspective of in situ degradation/remediation for coastal groundwater quality management. 展开更多
关键词 submarine groundwater discharge surface water and groundwater interaction algal bloom microbial ecology nutrient biogeochemistry ammonia-oxidizing archaea nitrate-utilizing bacteria Krka River Estuary
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Characterization of dissolved organic matter in submarine groundwater from a salt marsh in Chongming Island,China 被引量:1
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作者 Tangrong HE Fenfen ZHANG +2 位作者 Yali WANG Xiaogang CHEN Jinzhou DU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第1期128-141,共14页
Salt marshes are research hotspots of the carbon cycle in coastal zones because large amounts of atmospheric carbon dioxide is fi xed by salt marshes vegetation and stored in its biomass and soil.Dissolved organic car... Salt marshes are research hotspots of the carbon cycle in coastal zones because large amounts of atmospheric carbon dioxide is fi xed by salt marshes vegetation and stored in its biomass and soil.Dissolved organic carbon(DOC)in submarine groundwater(well water and pore water)in salt marshes plays an important role in advective exchange between the salt marshes and coastal waters.However,the molecular characteristics of DOC in salt marsh groundwater are poorly understood because of the complex DOC structures and hydrodynamic process.In this study,fl uorescent components and refractory DOC(RDOC)in submarine groundwater from a salt marsh(Chongming Island,China)and adjacent coastal water were characterized by fl uorescence spectroscopy and nuclear magnetic resonance spectroscopy.The fl uorescent components identifi ed by parallel factor analysis indicated that humic-like substances dominated the chromophoric dissolved organic matter in the submarine groundwater.The chromophoric dissolved organic matter and dissolved organic matter in the submarine groundwater had non-conservative behaviors because of additions from terrestrial humic substances.The nuclear magnetic resonance spectra indicated that bioactive substances(carbohydrates)contributed only 13.2%-14.8%of the dissolved organic matter in the submarine groundwater but carboxyl-rich alicyclic molecules(CRAMs),the main components of RDOC,contributed 64.5%of the dissolved organic matter.Carbohydrates and CRAMs contributed 16.4%and 61.7%of the dissolved organic matter in the coastal water,similar to the contributions for submarine groundwater.The DOC concentration in submarine groundwater was 386±294μmol/L,which was signifi cantly higher than that in coastal water(91±19μmol/L).The high DOC concentrations and>60%relative RDOC content suggested that submarine groundwater may be an important source of RDOC to coastal seawater.This information will be helpful for estimating the climate eff ects of salt marsh blue carbon. 展开更多
关键词 submarine groundwater dissolved organic carbon fl uorescence refractory dissolved organic carbon salt marsh Chongming Island
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Porewater-derived dissolved inorganic carbon and nutrient fluxes in a saltmarsh of the Changjiang River Estuary 被引量:1
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作者 Xiaogang Chen Jinzhou Du +1 位作者 Xueqing Yu Xiaoxiong Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第8期32-43,共12页
Saltmarshes are one of the most productive ecosystems,which contribute significantly to coastal nutrient and carbon budgets.However,limited information is available on soil nutrient and carbon losses via porewater exc... Saltmarshes are one of the most productive ecosystems,which contribute significantly to coastal nutrient and carbon budgets.However,limited information is available on soil nutrient and carbon losses via porewater exchange in saltmarshes.Here,porewater exchange and associated fluxes of nutrients and dissolved inorganic carbon(DIC)in the largest saltmarsh wetland(Chongming Dongtan)in the Changjiang River Estuary were quantified.Porewater exchange rate was estimated to be(37±35)cm/d during December 2017 using a radon(^(222)Rn)mass balance model.The porewater exchange delivered 67 mmol/(m^(2)·d),38 mmol/(m^(2)·d)and 2690 mmol/(m^(2)·d)of dissolved inorganic nitrogen(DIN),dissolved silicon(DSi)and DIC into the coastal waters,respectively.The dominant species of porewater DIN was NH_(4)^(+)(>99%of DIN).However,different with those in other ecosystems,the dissolved inorganic phosphorus(DIP)concentration in saltmarsh porewater was significantly lower than that in surface water,indicating that saltmarshes seem to be a DIP sink in Chongming Dongtan.The porewater-derived DIN,DSi and DIC accounted for 12%,5%and 18%of the riverine inputs,which are important components of coastal nutrient and carbon budgets.Furthermore,porewater-drived nutrients had obviously high N/P ratios(160–3995),indicating that the porewater exchange process may change the nutrient characteristics of the Changjiang River Estuary and further alter the coastal ecological environment. 展开更多
关键词 porewater exchange coastal wetlands saltwater intrusion nitrogen cycle blue carbon Changjiang River Estuary
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Re-examination of Fundamental Concepts of Heat, Work, Energy, Entropy, and Information Based on NGST 被引量:1
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作者 PAN Lingli CUI Weicheng 《Journal of Philosophy Study》 2022年第1期1-17,共17页
In order to use the framework of general system theory(GST)to unify the three mechanics subjects of classical mechanics,quantum mechanics,and relativistic mechanics,a new general system theory(NGST)is developed based ... In order to use the framework of general system theory(GST)to unify the three mechanics subjects of classical mechanics,quantum mechanics,and relativistic mechanics,a new general system theory(NGST)is developed based on a new ontology of ether and minds as the fundamental existences in the world.Based on this new ontology,many fundamental concepts have been detected to be ambiguously defined nowadays and particularly lack of ontological support.In our previous work,some of the fundamental concepts such as universe,world,time,space,matter,ether,mind,life,field,force have been redefined.The purpose of this paper is to clarify the concepts of energy,heat,work,entropy,and information in our NGST.This is an important and necessary step in the development of the NGST. 展开更多
关键词 new general system theory HEAT WORK ENERGY ENTROPY INFORMATION
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A 3D-printed microfluidic gradient concentration chip for rapid antibiotic-susceptibility testing 被引量:2
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作者 Huilin Zhang Yuan Yao +3 位作者 Yue Hui Lu Zhang Nanjia Zhou Feng Ju 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2022年第1期210-219,共10页
The rise of antibiotic resistance as one of the most serious global public health threats has necessitated the timely clinical diagnosis and precise treatment of deadly bacterial infections.To identify which types and... The rise of antibiotic resistance as one of the most serious global public health threats has necessitated the timely clinical diagnosis and precise treatment of deadly bacterial infections.To identify which types and doses of antibiotics remain effective for fighting against multi-drug-resistant pathogens,the development of rapid and accurate antibiotic-susceptibility testing(AST)is of primary importance.Conventional methods for AST in well-plate formats with disk diffusion or broth dilution are both labor-intensive and operationally tedious.The microfluidic chip provides a versatile tool for evaluating bacterial AST and resistant behaviors.In this paper,we develop an operationally simple,3D-printed microfluidic chip for AST which automatically deploys antibiotic concentration gradients and fluorescence intensity-based reporting to ideally reduce the report time for AST to within 5 h.By harnessing a commercially available,digital light processing(DLP)3D printing method that offers a rapid,high-precision microfluidic chip-manufacturing capability,we design and realize the accurate generation of on-chip antibiotic concentration gradients based on flow resistance and diffusion mechanisms.We further demonstrate the employment of the microfluidic chip for the AST of E.coli to representative clinical antibiotics of three classes:ampicillin,chloramphenicol,and kanamycin.The determined minimum inhibitory concentration values are comparable to those reported by conventional well-plate methods.Our proposed method demonstrates a promising approach for realizing robust,convenient,and automatable AST of clinical bacterial pathogens. 展开更多
关键词 MICROFLUIDICS Gradient concentration chip Digital light processing Antibiotic-susceptibility test BACTERIA
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Re-examination of the Two-Body Problem Using Our New General System Theory 被引量:2
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作者 PAN Lingli CUI Weicheng 《Journal of Philosophy Study》 2021年第12期891-913,共23页
It is well-known that philosophical conflicts exist among classical mechanics,quantum mechanics and relativistic mechanics.In order to use the framework of general system theory to unify these three mechanics subjects... It is well-known that philosophical conflicts exist among classical mechanics,quantum mechanics and relativistic mechanics.In order to use the framework of general system theory to unify these three mechanics subjects,a new general system theory is developed based on a new ontology of ether and minds as the fundamental existences in the world.The two-body problem is the simplest model in mechanics and in this paper,it is re-examined by using our new general system theory.It is found that the current description of the classical full two-body problem is inappropriate since the observer and the measurement apparatus have not been explicitly considered.After considering these,it is actually a three-body problem while only the special case of the Kepler problem is the two-body problem.By introducing the concepts of psychic force and psychic field,all the possible movement states in the two-body problem can be explained within the framework of classical mechanics.There is no need to change the meanings of many fundamental concepts,such as time,space,matter,mass,and energy as done in quantum mechanics and relativity theory.This points out a new direction for the unification of different theories. 展开更多
关键词 two-body problem new general system theory gravitational field psychic field classical mechanics quantum mechanics relativity theory
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Clarification of the Field Concept for a New General System Theory 被引量:2
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作者 PAN Lingli CUI Weicheng 《Journal of Philosophy Study》 2021年第10期737-747,共11页
Field is an essential concept for us to understand the physical phenomena in the universe.Since the field concept was proposed in electromagnetism during nineteenth century,the understanding of the field concept has e... Field is an essential concept for us to understand the physical phenomena in the universe.Since the field concept was proposed in electromagnetism during nineteenth century,the understanding of the field concept has experienced great changes.This paper re-examines the concept of field from its origin and evolution history,with the purpose of a better understanding of the concept in order to be used in our new general system theory to unify different theories.Our main conclusion is that the concept of field should not be regarded as an independent physical existence but a property of matter of both living and nonliving.Through a discussion on an isolated two-body system from the perspective of gravitational field,a psychic field is introduced to address the active force produced by living creatures with minds. 展开更多
关键词 FIELD electromagnetic field gravitational field psychic field mind-body problem
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On an Axiomatic Foundation for a Theory of Everything 被引量:1
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作者 CUI Weicheng 《Journal of Philosophy Study》 2021年第4期241-267,共27页
Whether a unified theory of everything(TOE)is possible or not is a philosophical question and yes or no can be chosen in a two-valued logic system.Currently the two schools are in conflict with each other.Based on the... Whether a unified theory of everything(TOE)is possible or not is a philosophical question and yes or no can be chosen in a two-valued logic system.Currently the two schools are in conflict with each other.Based on the relativity of simultaneity axiom proposed in this paper,the present author suggests to use a midway philosophy to replace the present materialist philosophy for modern sciences;then this conflict together with many other conflicts among different theories such as classical mechanics(CM),general relativity(GR),and quantum mechanics(QM)can be solved and a unified theory of everything for the world we can observe can be constructed.In this paper,the axiomatic foundation for a TOE is proposed which contains six fundamental axioms.Various problems related to these foundational issues are discussed.It is hoped that the present paper might show a new promise and a new direction for TOE which would be helpful for the further development of modern sciences. 展开更多
关键词 AXIOM mind-body problem the demarcation problem cause-effect law theory of everything(TOE)
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On the Trajectory Prediction of a Throwing Object Using New General System Theory
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作者 CUI Weicheng 《Journal of Philosophy Study》 2022年第2期53-64,共12页
Trajectory prediction for the movement of a given object is one of the main tasks for the classical mechanics but in orthodox quantum mechanics,this task was announced to be an impossibility for the(sub-)atomic partic... Trajectory prediction for the movement of a given object is one of the main tasks for the classical mechanics but in orthodox quantum mechanics,this task was announced to be an impossibility for the(sub-)atomic particles by famous Heisenberg’s uncertainty principle.Of course,such an epistemology is against the philosophical beliefs of many scientists and currently another version of trajectory quantum mechanics known as Bohmian mechanics also exists.In order to unify the conflicts among classical mechanics,quantum mechanics,and relativity theory,a new general system theory(NGST)was proposed by the present author and his colleagues.The purpose of this paper is to demonstrate that it is not the scale that matters but the living nature whether the object is lifeless or living.By using the psychic force concept introduced in NGST,Newton’s second law is applied to analyze five different types of objects.They are a stone,a coin,a cat,a person,and an electron.It is found that the classical mechanics has provided adequate room to explain the various newly observed phenomena for orthodox quantum mechanics and relativity theory and for human beings various parapsychological phenomena can also be explained by classical mechanics.Therefore,it is concluded that generalization of classical mechanics is adequate and no need to develop revolutionary quantum mechanics and relativity theory. 展开更多
关键词 object type TRAJECTORY new general system theory gravitational field psychic field classical mechanics quantum mechanics
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Symmetry-constrained quantum coupling in non-Fermi-liquid transport
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作者 李荣 佘振苏 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期495-509,共15页
Finding the common origin of non-Fermi liquids(NFLs) transport in high-temperature superconductors(HTSCs)has proven to be fundamentally challenging due to the prominence of various collective fluctuations.Here,we prop... Finding the common origin of non-Fermi liquids(NFLs) transport in high-temperature superconductors(HTSCs)has proven to be fundamentally challenging due to the prominence of various collective fluctuations.Here,we propose a comprehensive non-Hermitian Hamiltonian(NHH) for quantum coupling of multiple scattering mechanisms associated with four types of order fluctuations.It predicts that the anticommutation symmetry of the spinor fermions constrains the scattering rate to a unified quadrature scaling,i.e.,Γ=Γ_(1)+√Γ_(Q)^(2)+(μk_(B)T)^(2)+(vμ_(B)B)^(2)+(γ_(E)E)^(2).This scaling yields a comprehensive and accurate description of two widespread NFL behaviors in HTSCs,i.e.,a temperature-scaling crossover between quadratic and linear laws and the quadrature magnetoresistance,validated by several dozens of data sets for broad phase regimes.It reveals that the common origin of these behaviors is the spinor-symmetry-constrained quantum coupling of spin-wave and topological excitations of mesoscopic orders.Finally,we show that this NHH can be easily extended to other complex quantum fluids by specifying the corresponding symmetries.It is concluded that this work uncovers a critical organization principle(i.e.,the spinor symmetry) underlying the NFL transport,thus providing a novel theoretical framework to advance the transport theory of correlated electron systems. 展开更多
关键词 non-Fermi liquid non-Hermitian Hamiltonian anticommutation symmetry quantum coupling multiple scattering mechanisms
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Impact of flm thickness in laser‑induced periodic structures on amorphous Si flms
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作者 Liye Xu Jiao Geng +2 位作者 Liping Shi Weicheng Cui Min Qiu 《Frontiers of Optoelectronics》 EI CSCD 2023年第2期115-122,共8页
We report self-organized periodic nanostructures on amorphous silicon thin flms by femtosecond laser-induced oxidation.The dependence of structural periodicity on the thickness of silicon flms and the substrate materi... We report self-organized periodic nanostructures on amorphous silicon thin flms by femtosecond laser-induced oxidation.The dependence of structural periodicity on the thickness of silicon flms and the substrate materials is investigated.The results reveal that when silicon flm is 200 nm,the period of self-organized nanostructures is close to the laser wavelength and is insensitive to the substrates.In contrast,when the silicon flm is 50 nm,the period of nanostructures is much shorter than the laser wavelength,and is dependent on the substrates.Furthermore,we demonstrate that,for the thick silicon flms,quasi-cylindrical waves dominate the formation of periodic nanostructures,while for the thin silicon flms,the formation originates from slab waveguide modes.Finite-diference time-domain method-based numerical simulations support the experimental discoveries. 展开更多
关键词 Laser-induced periodic surface structures(LIPSS) Ultrafast optoelectronics Laser nanofabrication Quasicylindrical waves
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Scaling laws for the intermittent swimming performance of a flexible plate at low Reynolds number
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作者 Lin-lin Kang Shi-xian Gong +2 位作者 Xi-Yun Lu Wei-cheng Cui Di-xia Fan 《Journal of Hydrodynamics》 SCIE EI CSCD 2023年第4期803-810,共8页
Many species of fish and birds travel in intermittent style,yet the combined influence of intermittency and other body kinematics on the hydrodynamics of a self-propelled swimmer is not fully understood.By formulating... Many species of fish and birds travel in intermittent style,yet the combined influence of intermittency and other body kinematics on the hydrodynamics of a self-propelled swimmer is not fully understood.By formulating a reduced-order dynamical model for intermittent swimming,we uncover scaling laws that link the propulsive performance(cursing Reynolds number Rec,thrust T̄,input power P̄and cost of transport COT to body kinematics(duty cycle DC,flapping Reynolds number Ref).By comparing the derived scaling laws with the data from several previous studies and our numerical simulation,we demonstrate the validity of the theory.In addition,we found that Re_(c),T̄,P̄and COT all increase with the increase of DC,Ref.The model also reveals that the intermittent swimming may not be inherently more energy efficient than continuous swimming,depending on the ratio of drag coefficients between active bursting and coasting. 展开更多
关键词 PROPULSION intermittent swimming scaling law
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Multimaterial Embedded 3D Printing of Composite Reinforced Soft Actuators
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作者 Zhenhua Wang Boyu Zhang +5 位作者 Qu He Hao Chen Jizhe Wang Yuan Yao Nanjia Zhou Weicheng Cui 《Research》 SCIE EI CSCD 2023年第4期727-737,共11页
Soft pneumatic actuators(SPAs)have attracted enormous attention in the growing field of robotics.Among different SPAs,composite reinforced actuators(CRAs)are widely used because of their simple structure and high cont... Soft pneumatic actuators(SPAs)have attracted enormous attention in the growing field of robotics.Among different SPAs,composite reinforced actuators(CRAs)are widely used because of their simple structure and high controllability.However,multistep molding,a time-consuming method,is still the predominant fabrication method.Here,we propose a multimaterial embedded printing method(ME3P)to fabricate CRAs.In comparison with other 3-dimensional printing methods,our method improves fabrication flexibility greatly.Via the design and fabrication of the reinforced composites’patterns and different geometries of the soft body,we demonstrate actuators with programmable responses(elongation,contraction,twisting,bending,and helical and omnidirectional bending).Finite element analysis is employed for the prediction of pneumatic responses and the inverse design of actuators based on specific actuation needs.Lastly,we use tube-crawling robots as a model system to demonstrate our ability to fabricate complex soft robots for practical applications.This work demonstrates the versatility of ME3P for the future manufacturing of CRA-based soft robots. 展开更多
关键词 COMPOSITES COMPOSITE PRINTING
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Seasonal hydrological dynamics govern lifestyle preference of aquatic antibiotic resistome
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作者 Bob Adyari Liyuan Hou +5 位作者 Lanping Zhang Nengwang Chen Feng Ju Longji Zhu Chang-Ping Yu Anyi Hu 《Environmental Science and Ecotechnology》 SCIE 2023年第1期115-124,共10页
Antibiotic resistance genes(ARGs)are a well-known environmental concern.Yet,limited knowledge exists on the fate and transport of ARGs in deep freshwater reservoirs experiencing seasonal hydrological changes,especiall... Antibiotic resistance genes(ARGs)are a well-known environmental concern.Yet,limited knowledge exists on the fate and transport of ARGs in deep freshwater reservoirs experiencing seasonal hydrological changes,especially in the context of particle-attached(PA)and free-living(FL)lifestyles.Here,the ARG profiles were examined using high-throughput quantitative PCR in PA and FL lifestyles during four seasons representing two hydrological phenomena(vertical mixing and thermal stratification)in the Shuikou Reservoir(SR),Southern China.The results indicated that seasonal hydrological dynamics were critical for influencing the ARGs in PA and FL and the transition of ARGs between the two lifestyles.ARG profiles both in PA and FL were likely to be shaped by horizontal gene transfer.However,they exhibited distinct responses to the physicochemical(e.g.,nutrients and dissolved oxygen)changes under seasonal hydrological dynamics.The particle-association niche(PAN)index revealed 94 non-conservative ARGs(i.e.,no preferences for PA and FL)and 23 and 16 conservative ARGs preferring PA and FL lifestyles,respectively.A sharp decline in conservative ARGs under stratified hydrologic suggested seasonal influence on the ARGs transition between PA and FL lifestyles.Remarkably,the conservative ARGs(in PA or FL lifestyle)were more closely related to bacterial OTUs in their preferred lifestyle than their counterparts,indicating lifestyle-dependent ARG enrichment.Altogether,these findings enhanced our understanding of the ARG lifestyles and the role of seasonal hydrological changes in governing the ARG transition between the lifestyles in a typical deep freshwater ecosystem. 展开更多
关键词 Antibiotic resistance genes Particle-attached FREE-LIVING Vertical mixing and stratification Deep freshwater reservoir
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基于改进型AAF-RRT算法的AUV双层路径规划器 被引量:2
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作者 洪乐 宋长会 +1 位作者 杨平 崔维成 《Journal of Marine Science and Application》 CSCD 2022年第1期102-115,共14页
As autonomous underwater vehicles(AUVs)merely adopt the inductive obstacle avoidance mechanism to avoid collisions with underwater obstacles,path planners for underwater robots should consider the poor search efficien... As autonomous underwater vehicles(AUVs)merely adopt the inductive obstacle avoidance mechanism to avoid collisions with underwater obstacles,path planners for underwater robots should consider the poor search efficiency and inadequate collision-avoidance ability.To overcome these problems,a specific two-player path planner based on an improved algorithm is designed.First,by combing the artificial attractive field(AAF)of artificial potential field(APF)approach with the random rapidly exploring tree(RRT)algorithm,an improved AAF-RRT algorithm with a changing attractive force proportional to the Euler distance between the point to be extended and the goal point is proposed.Second,a twolayer path planner is designed with path smoothing,which combines global planning and local planning.Finally,as verified by the simulations,the improved AAF-RRT algorithm has the strongest searching ability and the ability to cross the narrow passage among the studied three algorithms,which are the basic RRT algorithm,the common AAF-RRT algorithm,and the improved AAF-RRT algorithm.Moreover,the two-layer path planner can plan a global and optimal path for AUVs if a sudden obstacle is added to the simulation environment. 展开更多
关键词 Autonomous underwater vehicles(AUVs) Path planner Random rapidly exploring tree(RRT) Artificial attractive field(AAF) Path smoothing
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On the Philosophical Ontology for a General System Theory 被引量:2
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作者 CUI Weicheng 《Journal of Philosophy Study》 2021年第6期443-458,共16页
System is a very general concept and theoretically speaking, every problem encountered can be modeled as a system. Thus, the general system theory (GST) proposed by Bertalanffy (1968) and developed by many others e.g.... System is a very general concept and theoretically speaking, every problem encountered can be modeled as a system. Thus, the general system theory (GST) proposed by Bertalanffy (1968) and developed by many others e.g. Bunge (1977;1979;1983a;1983b) and Maturana and Varela (1980;1987) could be treated as a theory of everything (TOE). However, it is well-known that the present version of GST has not reached the level of TOE because it lacks a clear ontology. Currently, quantum mechanics (QM), Newtonian mechanics (NM) and general relativity (GR), suitable for microscopic, macroscopic and cosmic phenomena respectively are based on very different ontologies. In this paper, a unified ontology for the general system theory which could be applied to any scale from micro to cosmic is proposed. It is expected that this could lay a foundation to generalize GST to TOE. 展开更多
关键词 system general system theory PHILOSOPHY METAPHYSICS ONTOLOGY MATTER MIND aether
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