Condensate gas reservoirs have attracted increasing attention in recent years due to their significant development potential and dual value from both natural gas and condensate oil.However,their exploitation is often ...Condensate gas reservoirs have attracted increasing attention in recent years due to their significant development potential and dual value from both natural gas and condensate oil.However,their exploitation is often hindered by the dual challenges of retrograde condensation and water invasion,which can markedly reduce recovery factors.CO_(2) injection offers a promising solution by alleviating condensate blockage,suppressing water influx,and simultaneously enabling geological CO_(2) storage.Accordingly,research on optimizing CO_(2) injection to mitigate formation damage is critical for the efficient development and management of edge-and bottom-water condensate gas reservoirs.In this study,a long-core displacement mechanism model was constructed using CMG-GEMTM andWinPropTM.The model simulates reservoir depletion from initial conditions(41.2 MPa,102.5℃)to the current reservoir pressure(13.5 MPa),followed by gas injection.It was then upscaled to the edge-and bottom-water reservoir scale to capture complex fluid phase behavior,enabling a multi-factor coupled optimization of CO_(2) injection strategies.Model reliability was verified through comparison with core experimental results.Subsequently,the effects of geological parameters(e.g.,reservoir permeability and rhythmic heterogeneity)and engineering parameters(e.g.,injection pressure and rate)on reservoir performance were systematically evaluated.The results indicate that appropriate target zone selection and optimization of injection pressure and rate—avoiding formation fracturing and preventing gas channeling—can substantially improve reservoir development outcomes.Applying this approach to the K Gas Reservoir,the optimal strategy involved injecting CO_(2) at a rate of 5×10^(4) m^(3)/d,restoring pressure to 22.5 MPa in a composite rhythmic reservoir with an average permeability of 10 mD.This scheme increased the condensate oil recovery factor by 18.7 percentage points(from 43.9%to 60.9%)while reducing the water-cut rise rate by approximately 34%.展开更多
Microcavity exciton-polaritons,formed by strong light-matter coupling,are essential for realizing Bose-Einstein condensation and low-threshold lasing.Such polaritonic lasing and condensation have been demonstrated in ...Microcavity exciton-polaritons,formed by strong light-matter coupling,are essential for realizing Bose-Einstein condensation and low-threshold lasing.Such polaritonic lasing and condensation have been demonstrated in Ⅲ-Ⅴ semiconductors at liquid helium temperatures.However,the complex fabrication of these microcavities and operating temperatures limit their room-temperature practical application.Here,we experimentally realize room-temperature exciton-polariton condensation and polaritonic lasing in a CsPbBr_(3)perovskite planar microcavity fabricated by the pressing process.Angleresolved photoluminescence spectra demonstrate the strong light-matter coupling and the formation of exciton-polaritons in such a pressed microcavity.Above the critical threshold,mass polaritons accumulating at the bottom of dispersion lead to a narrow emission linewidth and pronounced blueshift,further reinforcing the Bose-Einstein condensation and polaritonic lasing in this system.Our results offer a feasible and effective approach to investigate exciton-polariton condensation and polariton lasing at room temperature.展开更多
There are limited quantitative studies on condensate gas using microfluidics under high-pressure and high-temperature conditions.This study employed microfluidics chips based on real porous media structures to conduct...There are limited quantitative studies on condensate gas using microfluidics under high-pressure and high-temperature conditions.This study employed microfluidics chips based on real porous media structures to conduct constant volume depletion experiments and investigate the microscopic mechanisms of condensate gas recovery.The aim of the experiments was to reveal the phase-behavior differences between bulk-phase gas and gas contained in porous media.The results revealed that condensate oil recovery in microfluidics experiments was higher than that in PVT cell tests,and nonuniform condensation and evaporation were exclusively observed in the microfluidics experiments.Furthermore,lower pore connectivity resulted in higher depletion recovery,while more developed fractures led to reduced recovery.Specifically,the chip with fewer fractures achieved the highest recovery(71.15%),whereas the highly fractured chip exhibited the lowest recovery(56.11%).These findings demonstrate that oil saturation during the process of constant volume depletion(CVD)of gas condensate within porous media is lower than that observed in the PVT cell,thus providing experimental evidence for optimizing condensate gas development in field applications.展开更多
We investigate the chaotic and regular spatial structures of Bose–Einstein condensates(BECs)with a spatially modulated atom-atom interaction and without an external trapping potential.A BEC with a spatially modulated...We investigate the chaotic and regular spatial structures of Bose–Einstein condensates(BECs)with a spatially modulated atom-atom interaction and without an external trapping potential.A BEC with a spatially modulated atom-atom interaction is equivalent to being constrained by a nonlinear optical lattice.Theoretical analyses show the existence of a steady atomic current in the BEC with a spatially varying phase.Under perturbative conditions,the Melnikov chaos criteria of BECs with a spatially varying phase and a constant one are theoretically obtained,respectively.When the perturbative conditions cannot be satisfied,for a repulsive BEC with a spatially varying phase,numerical simulations demonstrate that changing the initial condition can eliminate the chaotic spatial structure and then the system transitions into a biperiodic spatial structure.Increasing the chemical potential can result in a transition from the biperiodic spatial structure to a single-periodic spatial structure.For an attractive BEC with a spatially varying phase,numerical simulations show that decreasing the chemical potential can lead to a high atomic density,but when the wave number of the laser inducing the optical Feshbach resonance exceeds a critical value,the atomic density falls back to a finite range.Regardless of whether the BEC has a spatially varying phase or a constant one,modulating the laser wave number can effectively suppress the chaotic spatial structure in the BEC and then force it into a regular spatial structure.展开更多
Compared with Pidgeon process,the relative vacuum continuous magnesium smelting process reduces the ratio of material to magnesium by changing raw materials and the direct reduction after calcination of prefabricated ...Compared with Pidgeon process,the relative vacuum continuous magnesium smelting process reduces the ratio of material to magnesium by changing raw materials and the direct reduction after calcination of prefabricated pellets,so that the energy consumption per ton of magnesium produced is reduced by 30∼40%,and the carbon emission is reduced by 43∼52%,breaking through the vacuum conditions to achieve continuous production.However,in the process of industrialization,it was found that the magnesium yield in the condenser was low.Therefore,this paper constructs a condenser model of relative vacuum continuous magnesium refining process,and comprehensively analyzes the condensation mechanism of magnesium vapor through simulation and experiment.It is found that the dynamic characteristics of magnesium vapor condensation is an important index to measure its continuity.Under the condition offlowing argon as the protective gas,when the condensation plate spacing is 10 cm,the surface roughness amplitude variance is 2,and the carrier gasflow rate is 20×10^(-3) m/s,the magnesium vapor has a better condensation effect,and the condensation efficiency formula is derived.展开更多
We propose a superposed Bessel optical lattice formed by multiple Bessel optical lattices.The static and rotational structures are formed in the presence of a spin-orbit coupling(SOC)interaction in the atomic in Bose...We propose a superposed Bessel optical lattice formed by multiple Bessel optical lattices.The static and rotational structures are formed in the presence of a spin-orbit coupling(SOC)interaction in the atomic in Bose–Einstein condensates are investigated,it is shown that the two structures can be manipulated by adjusting the parameters of the superposed Bessel optical lattices.The results show that the SOC interaction has an important effect on the two structures in the superposed Bessel optical lattices,and the SOC interaction can enhance the robustness of the structures.The Gaussian,toroidal and vortex superposition structures in the superposition lattice are presented,the interference processes in the steady state structures are analyzed,and the effects of SOC interactions on the Gaussian vortex and toroidal vortex structures are investigated,and the angular momentum of the vortex states can be increased by SOC interactions.展开更多
Elastomers are widely used in various fields owing to their excellent tensile properties.Recyclable and self-healing properties are key to extending the service life of elastomers.Accumulating evidence indicates that ...Elastomers are widely used in various fields owing to their excellent tensile properties.Recyclable and self-healing properties are key to extending the service life of elastomers.Accumulating evidence indicates that dynamic covalent chemistry has emerged as a powerful tool for constructing recyclable and self-healing materials.In this work,we demonstrate the preparation of a recyclable and self-healable polydimethylsiloxane(PDMS)elastomer based on the Knoevenagel condensation(KC)reaction.This PDMS elastomer was prepared by the KC reaction catalyzed by 4-dimethylaminopyridine(DMAP).The obtained PDMS elastomer exhibited an elongation at break of 266%,a tensile strength of 0.57 MPa,and a good thermal stability(Td=357℃).In addition,because of the presence of dynamic C=C bonds formed by the KC reaction and low glass transition temperature(Tg=-117℃).This PDMS exhibited good self-healing and recycling properties at room temperature and could be reprocessed by hot pressing.In addition,the PDMS elastomer exhibits good application prospects in the fields of adhesives and flexible electronic devices.展开更多
Utilizing superwettability micro/nanostructures to enhance the condensation heat transfer(CHT)performance of engineering materials has attracted great interest due to its values in basic research and technological inn...Utilizing superwettability micro/nanostructures to enhance the condensation heat transfer(CHT)performance of engineering materials has attracted great interest due to its values in basic research and technological innovations.Currently,exploring facile micro/nanofabrication approaches to create high-efficiency CHT surfaces has been one of research hotspots.In this work,we propose and demonstrate a type of new superwettability hybrid surface for high-efficiency CHT,which consists of superhydrophobic nanoneedle arrays and triangularly-patterned superhydrophilic microdots(SMDs).Such hybrid surface can be fabricated by the facile growth of densely-packed ZnO nanoneedles on the Zn-electroplated copper surface followed by fluorosilane modification and mask-assisted photodegradation.Through regulating the diameters and interspaces of SMDs,we obtain the optimized triangularly-patterned hybrid surface,which shows 42.7%higher CHT coefficient than the squarely-patterned hybrid surface and 58.5%higher CHT coefficient than the superhydrophobic surface.The key of such hybrid surface design is to considerably increase CHT coefficient brought about by SMD-triggered drop sweeping at the cost of slightly reducing heat transfer area of superhydrophobic functional zone for drop jumping.Such new strategy helps develop advanced CHT surfaces for high-efficiency electronic cooling and energy utilization.展开更多
The Josephson effect,an important quantum supercurrent phenomenon,has been extensively studied in superconductors and superfluids.In this paper,we investigate the rich physics of one-dimensional Josephson junctions in...The Josephson effect,an important quantum supercurrent phenomenon,has been extensively studied in superconductors and superfluids.In this paper,we investigate the rich physics of one-dimensional Josephson junctions in a red-detuned optical lattice with sodium(Na)quantum gas.A one-dimensional Josephson array is formed by setting up an optical lattice using a red-detuned laser.By characterizing the dependence of Josephson oscillations of the lattice depth,we experimentally demonstrate the Josephson current.The lattice depth is controlled by altering the lattice power,and our observations are consistent with theoretical predictions.These findings offer valuable insights into quantum coherent transport and the intricate dynamics inherent to superfluidity.展开更多
The self-condensation of n-butanal is an important reaction for carbon-chain extension in the commercial production of 2-ethylhexanol.Moreover,aldol condensation is one of the important reactions for the synthesis of ...The self-condensation of n-butanal is an important reaction for carbon-chain extension in the commercial production of 2-ethylhexanol.Moreover,aldol condensation is one of the important reactions for the synthesis of valuable organic chemicals or transportation fuels from biomass-derived platform compounds.So the investigation of the self-condensation of n-butanal is of significance in both academia and industry.This contribution reviewed the catalytic performance of heterogeneous catalysts in the self-condensation of n-butanal and the related reaction mechanism,network,and kinetics.The purpose of this review is to dedicate some help for further development of environmentally friendly catalysts and for a thorough comprehension of aldol condensation.展开更多
This work demonstrates that once a large number of pion is condensed in a high-energy hadron collision, the gamma-ray spectrum from π0decay takes on a typical broken power-law shape, which has been documented in many...This work demonstrates that once a large number of pion is condensed in a high-energy hadron collision, the gamma-ray spectrum from π0decay takes on a typical broken power-law shape, which has been documented in many astronomical observations, but we have not yet recognized it. We show that this pion condensation is caused by a large number of soft gluons condensed in protons.展开更多
Shale gas reservoirs typically contain numerous nanoscale pores,with pore size playing a significant role in influencing the gas behavior.To better understand the related mechanisms,this study employs the Gauge-GEMC m...Shale gas reservoirs typically contain numerous nanoscale pores,with pore size playing a significant role in influencing the gas behavior.To better understand the related mechanisms,this study employs the Gauge-GEMC molecular simulation method to systematically analyze the effects of various pore sizes(5,10,20,and 40 nm)on the phase behavior and dew point pressure of the shale gas reservoir components.The simulation results reveal that when pore sizes are smaller than 40 nm,the dew point pressure increases significantly as the pore size decreases.For instance,the dew point pressure in 5 nmpores is 20.3%higher than undermacroscopic conditions.Additionally,larger hydrocarbon molecules exhibit a tendency to aggregate in smaller pores,particularly in the 5–10 nm range,where the relative concentration of heavy hydrocarbons(C_(4+))increases markedly.Moreover,as the pore size becomes larger,the component distribution gradually aligns with experimental results observed under macroscopic conditions.This study demonstrates that pore effects are more pronounced for smaller sizes,directly influencing the aggregation of heavy hydrocarbons and the rise in dew point pressure.These phenomena could significantly impact the diffusivity of shale gas reservoirs and the recovery of condensate gas.The findings provide new theoretical insights into phase behavior changes in nanopores,offering valuable guidance for optimizing shale gas reservoir extraction strategies.展开更多
Thermal power generation systems have stringent requirements for water and steam quality,i.e.,condensate water quality is one of the critical issues.In this paper,we designed a two-layer model based on an autoencoder ...Thermal power generation systems have stringent requirements for water and steam quality,i.e.,condensate water quality is one of the critical issues.In this paper,we designed a two-layer model based on an autoencoder and expert knowledge to achieve the early warning and causal analysis of condensate water quality abnormalities.An early warning model using an autoencoder model is built based on the historical data affecting the condensate water quality.Next,an analytical model of condensate water quality abnormalities was then developed by combining expert knowledge and trend test algorithms.Two different datasets were used to test the proposed model,respectively.The accuracy of the autoencoder model in the short-period test set is 88.83%,which shows that the early warning model can accurately analyze the condensate water quality data and achieve the purpose of early warning.For the long-time period test set,the model can correctly identify each abnormality and simultaneously indicates the cause of the abnormal condensate water quality.The proposed model can correctly identify abnormal working conditions and it is applicable to other thermal power plants.展开更多
Kármán vortex street not only exists in nature,but also widely appears in engineering practice,which is of great significance for understanding superfluid.Parity-time(PT)symmetric potential provides a good p...Kármán vortex street not only exists in nature,but also widely appears in engineering practice,which is of great significance for understanding superfluid.Parity-time(PT)symmetric potential provides a good platform for the study of Kármán vortex streets.In this paper,different patterns of vortex shedding formed behind PT symmetric potential in Bose-Einstein condensate(BEC)are simulated numerically.Kármán vortex streets and others are discovered to emerge in the wake of a moving obstacle with appropriate parameters.Compared with BEC without PT symmetric potential,the frequency and amplitude of the drag force are more complex.The parametric regions of the combined modes are scattered around the Kármán vortex street.Numerical simulations indicate that the imaginary part of the PT symmetric potential affects the vortex structure patterns.Finally,we proposed an experimental protocol that may observe a Kármán vortex street.展开更多
Accurate descriptions of cloud droplet spectra from aerosol activation to vapor condensation using microphysical parameterization schemes are crucial for numerical simulations of precipitation and climate change in we...Accurate descriptions of cloud droplet spectra from aerosol activation to vapor condensation using microphysical parameterization schemes are crucial for numerical simulations of precipitation and climate change in weather forecasting and climate prediction models.Hence,the latest activation and triple-moment condensation schemes were combined to simulate and analyze the evolution characteristics of a cloud droplet spectrum from activation to condensation and compared with a high-resolution Lagrangian bin model and the current double-moment condensation schemes,in which the spectral shape parameter is fixed or diagnosed by an empirical formula.The results demonstrate that the latest schemes effectively capture the evolution characteristics of the cloud droplet spectrum during activation and condensation,which is in line with the performance of the bin model.The simulation of the latest activation and condensation schemes in a parcel model shows that the cloud droplet spectrum gradually widens and exhibits a multimodal distribution during the activation process,accompanied by a decrease in the spectral shape and slope parameters over time.Conversely,during the condensation process,the cloud droplet spectrum gradually narrows,resulting in increases in the spectral shape and slope parameters.However,these double-moment schemes fail to accurately replicate the evolution of the cloud droplet spectrum and its multimodal distribution characteristics.Furthermore,the latest schemes were coupled into a 1.5D cumulus model,and an observation case was simulated.The simulations confirm that the cloud droplet spectrum appears wider at the supersaturated cloud base and cloud top due to activation,while it becomes narrower at the middle altitudes of the cloud due to condensation growth.展开更多
Utilizing the dissipative Gross-Pitaevskii equation,we investigated the splitting dynamics of triply quantized vortices at finite temperature.Through linear perturbation analysis,we determined the excitation modes of ...Utilizing the dissipative Gross-Pitaevskii equation,we investigated the splitting dynamics of triply quantized vortices at finite temperature.Through linear perturbation analysis,we determined the excitation modes of these vortices across various dissipation parameters.We identified three unstable modes with p=2-,3-and 4-fold rotational symmetries,revealing a significant dynamic transition of the most unstable mode.That is,as the dissipation parameter increases the most unstable mode transitions from the p=2 mode to the p=3 mode.Throughout the entire range of dissipation parameters,the p=4 unstable mode is never the dominant mode.Subsequently,we performed nonlinear numerical simulations of the vortex splitting process.Under random perturbations we confirmed the dynamical transition,and under specific perturbations we confirmed the instability of the p=4 mode.Our findings on the finite temperature dependence of the splitting dynamics of triply quantized vortices are expected to be verifiable in experiments.展开更多
To investigate the possible geometric structure of the proton,an improved stringy proton model is constructed beyond the smallest distance approximation and treats the constituent(up and down)quark-initiated gluon tub...To investigate the possible geometric structure of the proton,an improved stringy proton model is constructed beyond the smallest distance approximation and treats the constituent(up and down)quark-initiated gluon tubes separately,where the constituent quarks are connected by gluon tubes which merge at the Fermat point of the quark triangle.The exclusive diffractive vector meson production process in electron-proton deep inelastic scattering is used to test the stringy structure of the proton.We calculate the coherent and incoherent differential cross sections of the exclusive diffractive J/Ψphotoproduction in the framework of Color Glass Condensate.The results show that our calculations are in good agreement with HERA data.Especially,our results give a better description of the HERA data at small t as compared to the ones from the hot spot model where the constituent quarks are independently distributed in the proton.Meanwhile,the radius of the proton resulting from the improved stringy proton model is coincident with the one from fitting to the data from GlueX Collaboration at Jefferson Lab,which indicates that the predictive power of the stringy proton model is significantly improved once it goes beyond the smallest distance approximation and treats the constituent quarks separately,instead of using the same profile for the up and down quarks initiated gluon tubes.Moreover,we assume that the transverse shape of the gluon tube satisfies Gaussian distribution,and explore the distribution width of the individual gluon tubes.We find an interesting result that the up quark-initiated gluon tube seems to have a larger distribution width than the down quarkinitiated gluon tube,which is favored by the HERA data.展开更多
As an important component of light hydrocarbon compounds,alkylbenzene compounds lack indicators to indicate the source of organic matter of light oils and condensates.Forty-one oil samples from the Tarim Basin and Bei...As an important component of light hydrocarbon compounds,alkylbenzene compounds lack indicators to indicate the source of organic matter of light oils and condensates.Forty-one oil samples from the Tarim Basin and Beibuwan Basin were analyzed by comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GC-TOFMS).The concentration distributions of thirteen light hydrocarbon compounds with organic matter source and sedimentary environment indication were studied.There is no significant difference in the concentrations of 1-methylpropylbenzene(MPB)in all studied oils.However,the concentrations of 2-MPB in the Tarim swamp oils are higher than that in the Beibuwan lacustrine oils and Tarim marine oils.Based on the significant concentration difference of 1-and 2-MPB in all studied oils,1-/2-MPB(MPBr)was proposed as an indicator to identify the source of organic matter in crude oils.The MPBr values greater than 1.5 indicate that the crude oil mainly comes from lower aquatic organisms,bacteria,and algae.The MPBr values greater than 1.0 and less than 1.5 indicate that crude oil was derived from the combined contributions of lower aquatic organisms,bacteria and algae,and terrestrial higher plants.The MPBr values less than 1.0 suggest that the crude oil was mainly derived from terrigenous higher plants.The MPBr values in crude oils basically are not or slightly affected by depositional environment and secondary alteration.The MPBr values can be used to infer the organic matter origin in sediments,especially for the lack of biomarkers of light oils and condensates.展开更多
Introducing PT-symmetric generalized Scarf-Ⅱpotentials into the three-coupled nonlinear Gross-Pitaevskii equations offers a new way to seek stable soliton states in quasi-onedimensional spin-1 Bose-Einstein condensat...Introducing PT-symmetric generalized Scarf-Ⅱpotentials into the three-coupled nonlinear Gross-Pitaevskii equations offers a new way to seek stable soliton states in quasi-onedimensional spin-1 Bose-Einstein condensates.In scenarios where the spin-independent parameter c_(0)and the spin-dependent parameter c_(2)vary,we use both analytical and numerical methods to investigate the three-coupled nonlinear Gross-Pitaevskii equations with PT-symmetric generalized Scarf-Ⅱpotentials.We obtain analytical soliton states and find that simply modulating c_(2)may change the analytical soliton states from unstable to stable.Additionally,we obtain numerically stable double-hump soliton states propagating in the form of periodic oscillations,exhibiting distinct behavior in energy exchange.For further investigation,we discuss the interaction of numerical double-hump solitons with Gaussian solitons and observe the transfer of energy among the three components.These findings may contribute to a deeper understanding of solitons in Bose-Einstein condensates with PT-symmetric potentials and may hold significance for both theoretical understanding and experimental design in related physics experiments.展开更多
Oxidation of organic amines(OAs)or aromatic hydrocarbons(AHs)produces carbonyls,which further react with OAs to form carbonyl-amine condensation products,threatening environmental quality and human health.However,ther...Oxidation of organic amines(OAs)or aromatic hydrocarbons(AHs)produces carbonyls,which further react with OAs to form carbonyl-amine condensation products,threatening environmental quality and human health.However,there is still a lack of systematic understanding of the carbonyl-amine condensation reaction processes of OAs or between OAs and AHs,and subsequent environmental health impact.This work systematically investigated the carbonyl-amine condensation coupled ozonolysis kinetics,reaction mechanism,secondary organic aerosol(SOA)formation and cytotoxicity fromthe mixture of dipropylamine(DPA)and styrene(STY)by a combined method of productmass spectrometry identification,particle property analysis and cell exposure evaluation.The results from ozonolysis of DPA and STY mixture revealed that STY inhibited the ozonolysis of DPA to different degrees to accelerate its own decay rate.The barycenter of carbonyl-amine condensation reactionswas shifted from inside of DPA to between DPA and STY,which accelerated STY ozonolysis,but slowed down DPA ozonolysis.For the first time,ozonolysis of DPA and STY mixture to complex carbonyl-amine condensation products through the reactions of DPA with its carbonyl products,DPA with STY’s carbonyl products and DPA’s bond breakage product with STY’s carbonyl products was confirmed.These condensation products significantly contributed to the formation and growth of SOA.The SOA containing particulate carbonyl-amine condensation products showed definite cytotoxicity.These findings are helpful to deeply and comprehensively understand the transformation,fate and environmental health effects of mixed organics in atmospheric environment.展开更多
基金supported by the National Natural Science Foundation of China(No.52474047).
文摘Condensate gas reservoirs have attracted increasing attention in recent years due to their significant development potential and dual value from both natural gas and condensate oil.However,their exploitation is often hindered by the dual challenges of retrograde condensation and water invasion,which can markedly reduce recovery factors.CO_(2) injection offers a promising solution by alleviating condensate blockage,suppressing water influx,and simultaneously enabling geological CO_(2) storage.Accordingly,research on optimizing CO_(2) injection to mitigate formation damage is critical for the efficient development and management of edge-and bottom-water condensate gas reservoirs.In this study,a long-core displacement mechanism model was constructed using CMG-GEMTM andWinPropTM.The model simulates reservoir depletion from initial conditions(41.2 MPa,102.5℃)to the current reservoir pressure(13.5 MPa),followed by gas injection.It was then upscaled to the edge-and bottom-water reservoir scale to capture complex fluid phase behavior,enabling a multi-factor coupled optimization of CO_(2) injection strategies.Model reliability was verified through comparison with core experimental results.Subsequently,the effects of geological parameters(e.g.,reservoir permeability and rhythmic heterogeneity)and engineering parameters(e.g.,injection pressure and rate)on reservoir performance were systematically evaluated.The results indicate that appropriate target zone selection and optimization of injection pressure and rate—avoiding formation fracturing and preventing gas channeling—can substantially improve reservoir development outcomes.Applying this approach to the K Gas Reservoir,the optimal strategy involved injecting CO_(2) at a rate of 5×10^(4) m^(3)/d,restoring pressure to 22.5 MPa in a composite rhythmic reservoir with an average permeability of 10 mD.This scheme increased the condensate oil recovery factor by 18.7 percentage points(from 43.9%to 60.9%)while reducing the water-cut rise rate by approximately 34%.
基金support from theNational Natural Science Foundation(Grant No.12204111)the National Key Research and Development Program ofChina(Grant No.2023YFA1407100)Shanghai Pilot Pro-gram for Basic Research(Grant No.22JC1403202)。
文摘Microcavity exciton-polaritons,formed by strong light-matter coupling,are essential for realizing Bose-Einstein condensation and low-threshold lasing.Such polaritonic lasing and condensation have been demonstrated in Ⅲ-Ⅴ semiconductors at liquid helium temperatures.However,the complex fabrication of these microcavities and operating temperatures limit their room-temperature practical application.Here,we experimentally realize room-temperature exciton-polariton condensation and polaritonic lasing in a CsPbBr_(3)perovskite planar microcavity fabricated by the pressing process.Angleresolved photoluminescence spectra demonstrate the strong light-matter coupling and the formation of exciton-polaritons in such a pressed microcavity.Above the critical threshold,mass polaritons accumulating at the bottom of dispersion lead to a narrow emission linewidth and pronounced blueshift,further reinforcing the Bose-Einstein condensation and polaritonic lasing in this system.Our results offer a feasible and effective approach to investigate exciton-polariton condensation and polariton lasing at room temperature.
基金supported by the National Natural Science Foundation of China(grant number 52404044).
文摘There are limited quantitative studies on condensate gas using microfluidics under high-pressure and high-temperature conditions.This study employed microfluidics chips based on real porous media structures to conduct constant volume depletion experiments and investigate the microscopic mechanisms of condensate gas recovery.The aim of the experiments was to reveal the phase-behavior differences between bulk-phase gas and gas contained in porous media.The results revealed that condensate oil recovery in microfluidics experiments was higher than that in PVT cell tests,and nonuniform condensation and evaporation were exclusively observed in the microfluidics experiments.Furthermore,lower pore connectivity resulted in higher depletion recovery,while more developed fractures led to reduced recovery.Specifically,the chip with fewer fractures achieved the highest recovery(71.15%),whereas the highly fractured chip exhibited the lowest recovery(56.11%).These findings demonstrate that oil saturation during the process of constant volume depletion(CVD)of gas condensate within porous media is lower than that observed in the PVT cell,thus providing experimental evidence for optimizing condensate gas development in field applications.
基金Projects supported by the Natural Science Foundation of Hunan Province(2016JJ6020)the Scientific Research Fund of Hunan Provincial Education Department(18A436)the Scientific Research Fund of Hunan First normal University(XYS13N16)。
文摘We investigate the chaotic and regular spatial structures of Bose–Einstein condensates(BECs)with a spatially modulated atom-atom interaction and without an external trapping potential.A BEC with a spatially modulated atom-atom interaction is equivalent to being constrained by a nonlinear optical lattice.Theoretical analyses show the existence of a steady atomic current in the BEC with a spatially varying phase.Under perturbative conditions,the Melnikov chaos criteria of BECs with a spatially varying phase and a constant one are theoretically obtained,respectively.When the perturbative conditions cannot be satisfied,for a repulsive BEC with a spatially varying phase,numerical simulations demonstrate that changing the initial condition can eliminate the chaotic spatial structure and then the system transitions into a biperiodic spatial structure.Increasing the chemical potential can result in a transition from the biperiodic spatial structure to a single-periodic spatial structure.For an attractive BEC with a spatially varying phase,numerical simulations show that decreasing the chemical potential can lead to a high atomic density,but when the wave number of the laser inducing the optical Feshbach resonance exceeds a critical value,the atomic density falls back to a finite range.Regardless of whether the BEC has a spatially varying phase or a constant one,modulating the laser wave number can effectively suppress the chaotic spatial structure in the BEC and then force it into a regular spatial structure.
基金the National Natural Science Foundation of China(U1908225,U1702253)the Special Funds for Ba-sic Research Operations of Central Universities(N182515007,N170908001,N2025004).
文摘Compared with Pidgeon process,the relative vacuum continuous magnesium smelting process reduces the ratio of material to magnesium by changing raw materials and the direct reduction after calcination of prefabricated pellets,so that the energy consumption per ton of magnesium produced is reduced by 30∼40%,and the carbon emission is reduced by 43∼52%,breaking through the vacuum conditions to achieve continuous production.However,in the process of industrialization,it was found that the magnesium yield in the condenser was low.Therefore,this paper constructs a condenser model of relative vacuum continuous magnesium refining process,and comprehensively analyzes the condensation mechanism of magnesium vapor through simulation and experiment.It is found that the dynamic characteristics of magnesium vapor condensation is an important index to measure its continuity.Under the condition offlowing argon as the protective gas,when the condensation plate spacing is 10 cm,the surface roughness amplitude variance is 2,and the carrier gasflow rate is 20×10^(-3) m/s,the magnesium vapor has a better condensation effect,and the condensation efficiency formula is derived.
基金supported by the Longdong University Doctoral Fund Program Projects(Grant Nos.XYBYZK2227,XYBYZK2219).
文摘We propose a superposed Bessel optical lattice formed by multiple Bessel optical lattices.The static and rotational structures are formed in the presence of a spin-orbit coupling(SOC)interaction in the atomic in Bose–Einstein condensates are investigated,it is shown that the two structures can be manipulated by adjusting the parameters of the superposed Bessel optical lattices.The results show that the SOC interaction has an important effect on the two structures in the superposed Bessel optical lattices,and the SOC interaction can enhance the robustness of the structures.The Gaussian,toroidal and vortex superposition structures in the superposition lattice are presented,the interference processes in the steady state structures are analyzed,and the effects of SOC interactions on the Gaussian vortex and toroidal vortex structures are investigated,and the angular momentum of the vortex states can be increased by SOC interactions.
基金supported by the National Natural Science Foundation of China(Nos.51973025 and 52222307)Jilin Science and Technology Bureau(Nos.20220204107YY and 20230204086YY)+1 种基金Changchun Science and Technology Bureau(No.21ZGY06)Jilin Province Development and Reform Commission(No.2023C028-4).
文摘Elastomers are widely used in various fields owing to their excellent tensile properties.Recyclable and self-healing properties are key to extending the service life of elastomers.Accumulating evidence indicates that dynamic covalent chemistry has emerged as a powerful tool for constructing recyclable and self-healing materials.In this work,we demonstrate the preparation of a recyclable and self-healable polydimethylsiloxane(PDMS)elastomer based on the Knoevenagel condensation(KC)reaction.This PDMS elastomer was prepared by the KC reaction catalyzed by 4-dimethylaminopyridine(DMAP).The obtained PDMS elastomer exhibited an elongation at break of 266%,a tensile strength of 0.57 MPa,and a good thermal stability(Td=357℃).In addition,because of the presence of dynamic C=C bonds formed by the KC reaction and low glass transition temperature(Tg=-117℃).This PDMS exhibited good self-healing and recycling properties at room temperature and could be reprocessed by hot pressing.In addition,the PDMS elastomer exhibits good application prospects in the fields of adhesives and flexible electronic devices.
基金supported by National Natural Science Foundation of China(No.21573276)Natural Science Foundation of Jiangsu Province(No.BK20170007)Jiangsu Funding Program for Excellent Postdoctoral Talent(No.2022ZB846).
文摘Utilizing superwettability micro/nanostructures to enhance the condensation heat transfer(CHT)performance of engineering materials has attracted great interest due to its values in basic research and technological innovations.Currently,exploring facile micro/nanofabrication approaches to create high-efficiency CHT surfaces has been one of research hotspots.In this work,we propose and demonstrate a type of new superwettability hybrid surface for high-efficiency CHT,which consists of superhydrophobic nanoneedle arrays and triangularly-patterned superhydrophilic microdots(SMDs).Such hybrid surface can be fabricated by the facile growth of densely-packed ZnO nanoneedles on the Zn-electroplated copper surface followed by fluorosilane modification and mask-assisted photodegradation.Through regulating the diameters and interspaces of SMDs,we obtain the optimized triangularly-patterned hybrid surface,which shows 42.7%higher CHT coefficient than the squarely-patterned hybrid surface and 58.5%higher CHT coefficient than the superhydrophobic surface.The key of such hybrid surface design is to considerably increase CHT coefficient brought about by SMD-triggered drop sweeping at the cost of slightly reducing heat transfer area of superhydrophobic functional zone for drop jumping.Such new strategy helps develop advanced CHT surfaces for high-efficiency electronic cooling and energy utilization.
基金Project supported by the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0302103)the National Natural Science Foundation of China(Grant Nos.62325505,62020106014,62175140,62475138,92165106,12104276)the Shanxi Province Graduate Student Research Innovation Project(Grant No.2024KY105)。
文摘The Josephson effect,an important quantum supercurrent phenomenon,has been extensively studied in superconductors and superfluids.In this paper,we investigate the rich physics of one-dimensional Josephson junctions in a red-detuned optical lattice with sodium(Na)quantum gas.A one-dimensional Josephson array is formed by setting up an optical lattice using a red-detuned laser.By characterizing the dependence of Josephson oscillations of the lattice depth,we experimentally demonstrate the Josephson current.The lattice depth is controlled by altering the lattice power,and our observations are consistent with theoretical predictions.These findings offer valuable insights into quantum coherent transport and the intricate dynamics inherent to superfluidity.
基金supported by the National Natural Science Foundation of China(21476058,U21A20306,21506046 and 21978066)。
文摘The self-condensation of n-butanal is an important reaction for carbon-chain extension in the commercial production of 2-ethylhexanol.Moreover,aldol condensation is one of the important reactions for the synthesis of valuable organic chemicals or transportation fuels from biomass-derived platform compounds.So the investigation of the self-condensation of n-butanal is of significance in both academia and industry.This contribution reviewed the catalytic performance of heterogeneous catalysts in the self-condensation of n-butanal and the related reaction mechanism,network,and kinetics.The purpose of this review is to dedicate some help for further development of environmentally friendly catalysts and for a thorough comprehension of aldol condensation.
基金partly supported by the National Key R&D Program of China (Grant No. 2023YFB3001502)the National Natural Science of China (Grant No. 12373002)。
文摘This work demonstrates that once a large number of pion is condensed in a high-energy hadron collision, the gamma-ray spectrum from π0decay takes on a typical broken power-law shape, which has been documented in many astronomical observations, but we have not yet recognized it. We show that this pion condensation is caused by a large number of soft gluons condensed in protons.
基金financially supported by the Hubei Province Education Department of China(Project Name:Research on the Formation Mechanism and Microscopic Characteristics of Tight Dolomite Reservoirs in Salt Lake Basins:A Case Study of the Xingouzui Formation in the Jianghan Basin,Grant No.B2020032).
文摘Shale gas reservoirs typically contain numerous nanoscale pores,with pore size playing a significant role in influencing the gas behavior.To better understand the related mechanisms,this study employs the Gauge-GEMC molecular simulation method to systematically analyze the effects of various pore sizes(5,10,20,and 40 nm)on the phase behavior and dew point pressure of the shale gas reservoir components.The simulation results reveal that when pore sizes are smaller than 40 nm,the dew point pressure increases significantly as the pore size decreases.For instance,the dew point pressure in 5 nmpores is 20.3%higher than undermacroscopic conditions.Additionally,larger hydrocarbon molecules exhibit a tendency to aggregate in smaller pores,particularly in the 5–10 nm range,where the relative concentration of heavy hydrocarbons(C_(4+))increases markedly.Moreover,as the pore size becomes larger,the component distribution gradually aligns with experimental results observed under macroscopic conditions.This study demonstrates that pore effects are more pronounced for smaller sizes,directly influencing the aggregation of heavy hydrocarbons and the rise in dew point pressure.These phenomena could significantly impact the diffusivity of shale gas reservoirs and the recovery of condensate gas.The findings provide new theoretical insights into phase behavior changes in nanopores,offering valuable guidance for optimizing shale gas reservoir extraction strategies.
基金supported by the Jingneng Shiyan Thermal Power Co.,Ltd.(TPRI/TR-CA-006-2023)Huaihe Energy Power Group Co.,Ltd.(TPRI/TR-CA-040-2023)Xi'an Thermal Power Research Institute Co.,Ltd.(TPRI/TR-CA-110-2021A/H1).
文摘Thermal power generation systems have stringent requirements for water and steam quality,i.e.,condensate water quality is one of the critical issues.In this paper,we designed a two-layer model based on an autoencoder and expert knowledge to achieve the early warning and causal analysis of condensate water quality abnormalities.An early warning model using an autoencoder model is built based on the historical data affecting the condensate water quality.Next,an analytical model of condensate water quality abnormalities was then developed by combining expert knowledge and trend test algorithms.Two different datasets were used to test the proposed model,respectively.The accuracy of the autoencoder model in the short-period test set is 88.83%,which shows that the early warning model can accurately analyze the condensate water quality data and achieve the purpose of early warning.For the long-time period test set,the model can correctly identify each abnormality and simultaneously indicates the cause of the abnormal condensate water quality.The proposed model can correctly identify abnormal working conditions and it is applicable to other thermal power plants.
基金supported by the National Natural Science Foundation of China under Grant Nos.12065022,12147213。
文摘Kármán vortex street not only exists in nature,but also widely appears in engineering practice,which is of great significance for understanding superfluid.Parity-time(PT)symmetric potential provides a good platform for the study of Kármán vortex streets.In this paper,different patterns of vortex shedding formed behind PT symmetric potential in Bose-Einstein condensate(BEC)are simulated numerically.Kármán vortex streets and others are discovered to emerge in the wake of a moving obstacle with appropriate parameters.Compared with BEC without PT symmetric potential,the frequency and amplitude of the drag force are more complex.The parametric regions of the combined modes are scattered around the Kármán vortex street.Numerical simulations indicate that the imaginary part of the PT symmetric potential affects the vortex structure patterns.Finally,we proposed an experimental protocol that may observe a Kármán vortex street.
基金supported by the National Natural Science Foundations of China(Grant Nos.42305163 and U22A20577)the Construction Project of Weather Modification Ability in Central China(Grant No.ZQC-H22256)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0760300)the Projects of the Earth System Numerical Simulation Facility(Grant Nos.2024-EL-PT-000707,2023-ELPT-000482,2023-EL-ZD-00026,and 2022-EL-PT-00083)the STS Program of the Inner Mongolia Meteorological Service,Chongqing Institute of Green and Intelligent Technology,Chinese Academy of Sciences,and Institute of Atmospheric Physics,Chinese Academy of Sciences(Grant No.2021CG0047)。
文摘Accurate descriptions of cloud droplet spectra from aerosol activation to vapor condensation using microphysical parameterization schemes are crucial for numerical simulations of precipitation and climate change in weather forecasting and climate prediction models.Hence,the latest activation and triple-moment condensation schemes were combined to simulate and analyze the evolution characteristics of a cloud droplet spectrum from activation to condensation and compared with a high-resolution Lagrangian bin model and the current double-moment condensation schemes,in which the spectral shape parameter is fixed or diagnosed by an empirical formula.The results demonstrate that the latest schemes effectively capture the evolution characteristics of the cloud droplet spectrum during activation and condensation,which is in line with the performance of the bin model.The simulation of the latest activation and condensation schemes in a parcel model shows that the cloud droplet spectrum gradually widens and exhibits a multimodal distribution during the activation process,accompanied by a decrease in the spectral shape and slope parameters over time.Conversely,during the condensation process,the cloud droplet spectrum gradually narrows,resulting in increases in the spectral shape and slope parameters.However,these double-moment schemes fail to accurately replicate the evolution of the cloud droplet spectrum and its multimodal distribution characteristics.Furthermore,the latest schemes were coupled into a 1.5D cumulus model,and an observation case was simulated.The simulations confirm that the cloud droplet spectrum appears wider at the supersaturated cloud base and cloud top due to activation,while it becomes narrower at the middle altitudes of the cloud due to condensation growth.
基金provided by the Guangdong Basic and Applied Basic Research Foundation of China(Grant Nos.2024A1515012552,2022A1515011938,2022A1515012425)the National Natural Science Foundation of China(Grant No.12005088)the support received from Lingnan Normal University(Grant Nos.YL20200203,ZL1930)。
文摘Utilizing the dissipative Gross-Pitaevskii equation,we investigated the splitting dynamics of triply quantized vortices at finite temperature.Through linear perturbation analysis,we determined the excitation modes of these vortices across various dissipation parameters.We identified three unstable modes with p=2-,3-and 4-fold rotational symmetries,revealing a significant dynamic transition of the most unstable mode.That is,as the dissipation parameter increases the most unstable mode transitions from the p=2 mode to the p=3 mode.Throughout the entire range of dissipation parameters,the p=4 unstable mode is never the dominant mode.Subsequently,we performed nonlinear numerical simulations of the vortex splitting process.Under random perturbations we confirmed the dynamical transition,and under specific perturbations we confirmed the instability of the p=4 mode.Our findings on the finite temperature dependence of the splitting dynamics of triply quantized vortices are expected to be verifiable in experiments.
基金supported by the National Natural Science Foundation of China under Grant No.12165004 and and Key Grant No.12061141008the Basic and Applied Basic Research Project of Guangzhou Science and Technology Bureau under Grant No.202201011324+1 种基金the Education Department of Guizhou Province under Grant No.QJJ[2022]016the National Key Research and Development Program of China under Grant Nos.2024YFA1610800 and 2022YFA1602103。
文摘To investigate the possible geometric structure of the proton,an improved stringy proton model is constructed beyond the smallest distance approximation and treats the constituent(up and down)quark-initiated gluon tubes separately,where the constituent quarks are connected by gluon tubes which merge at the Fermat point of the quark triangle.The exclusive diffractive vector meson production process in electron-proton deep inelastic scattering is used to test the stringy structure of the proton.We calculate the coherent and incoherent differential cross sections of the exclusive diffractive J/Ψphotoproduction in the framework of Color Glass Condensate.The results show that our calculations are in good agreement with HERA data.Especially,our results give a better description of the HERA data at small t as compared to the ones from the hot spot model where the constituent quarks are independently distributed in the proton.Meanwhile,the radius of the proton resulting from the improved stringy proton model is coincident with the one from fitting to the data from GlueX Collaboration at Jefferson Lab,which indicates that the predictive power of the stringy proton model is significantly improved once it goes beyond the smallest distance approximation and treats the constituent quarks separately,instead of using the same profile for the up and down quarks initiated gluon tubes.Moreover,we assume that the transverse shape of the gluon tube satisfies Gaussian distribution,and explore the distribution width of the individual gluon tubes.We find an interesting result that the up quark-initiated gluon tube seems to have a larger distribution width than the down quarkinitiated gluon tube,which is favored by the HERA data.
基金supported by Doctor's Scientific Research Initiation Project of Yan'an University(YAU202213093)National Nature Science Foundation of China(Grant No.41503029).
文摘As an important component of light hydrocarbon compounds,alkylbenzene compounds lack indicators to indicate the source of organic matter of light oils and condensates.Forty-one oil samples from the Tarim Basin and Beibuwan Basin were analyzed by comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GC-TOFMS).The concentration distributions of thirteen light hydrocarbon compounds with organic matter source and sedimentary environment indication were studied.There is no significant difference in the concentrations of 1-methylpropylbenzene(MPB)in all studied oils.However,the concentrations of 2-MPB in the Tarim swamp oils are higher than that in the Beibuwan lacustrine oils and Tarim marine oils.Based on the significant concentration difference of 1-and 2-MPB in all studied oils,1-/2-MPB(MPBr)was proposed as an indicator to identify the source of organic matter in crude oils.The MPBr values greater than 1.5 indicate that the crude oil mainly comes from lower aquatic organisms,bacteria,and algae.The MPBr values greater than 1.0 and less than 1.5 indicate that crude oil was derived from the combined contributions of lower aquatic organisms,bacteria and algae,and terrestrial higher plants.The MPBr values less than 1.0 suggest that the crude oil was mainly derived from terrigenous higher plants.The MPBr values in crude oils basically are not or slightly affected by depositional environment and secondary alteration.The MPBr values can be used to infer the organic matter origin in sediments,especially for the lack of biomarkers of light oils and condensates.
基金supported by NSFC under Grant No.12272403Beijing Training Program of Innovation under Grant No.S202410019024。
文摘Introducing PT-symmetric generalized Scarf-Ⅱpotentials into the three-coupled nonlinear Gross-Pitaevskii equations offers a new way to seek stable soliton states in quasi-onedimensional spin-1 Bose-Einstein condensates.In scenarios where the spin-independent parameter c_(0)and the spin-dependent parameter c_(2)vary,we use both analytical and numerical methods to investigate the three-coupled nonlinear Gross-Pitaevskii equations with PT-symmetric generalized Scarf-Ⅱpotentials.We obtain analytical soliton states and find that simply modulating c_(2)may change the analytical soliton states from unstable to stable.Additionally,we obtain numerically stable double-hump soliton states propagating in the form of periodic oscillations,exhibiting distinct behavior in energy exchange.For further investigation,we discuss the interaction of numerical double-hump solitons with Gaussian solitons and observe the transfer of energy among the three components.These findings may contribute to a deeper understanding of solitons in Bose-Einstein condensates with PT-symmetric potentials and may hold significance for both theoretical understanding and experimental design in related physics experiments.
基金supported by the National Natural Science Foundation of China(Nos.42177354 and 42020104001)the National Key R&D Program of China(No.2019YFC0214402)+1 种基金the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Z032)Guangdong Basic and Applied Basic Research Foundation(No.2019B151502064).
文摘Oxidation of organic amines(OAs)or aromatic hydrocarbons(AHs)produces carbonyls,which further react with OAs to form carbonyl-amine condensation products,threatening environmental quality and human health.However,there is still a lack of systematic understanding of the carbonyl-amine condensation reaction processes of OAs or between OAs and AHs,and subsequent environmental health impact.This work systematically investigated the carbonyl-amine condensation coupled ozonolysis kinetics,reaction mechanism,secondary organic aerosol(SOA)formation and cytotoxicity fromthe mixture of dipropylamine(DPA)and styrene(STY)by a combined method of productmass spectrometry identification,particle property analysis and cell exposure evaluation.The results from ozonolysis of DPA and STY mixture revealed that STY inhibited the ozonolysis of DPA to different degrees to accelerate its own decay rate.The barycenter of carbonyl-amine condensation reactionswas shifted from inside of DPA to between DPA and STY,which accelerated STY ozonolysis,but slowed down DPA ozonolysis.For the first time,ozonolysis of DPA and STY mixture to complex carbonyl-amine condensation products through the reactions of DPA with its carbonyl products,DPA with STY’s carbonyl products and DPA’s bond breakage product with STY’s carbonyl products was confirmed.These condensation products significantly contributed to the formation and growth of SOA.The SOA containing particulate carbonyl-amine condensation products showed definite cytotoxicity.These findings are helpful to deeply and comprehensively understand the transformation,fate and environmental health effects of mixed organics in atmospheric environment.
