Flow pattern visualization and nonlinear analysis of gas-liquid mixing process with top-blowing gas stirring

The evaluation of the mixing effect of gas-liquid two-phase flow during the top-blown gas agitation mixing is one of the difficulties in the testing field, especially in the process of using the model method to study the metallurgical top-blowing process. In order to evaluate the effect of gas-liquid two-phase flow mixing, a gas chromatography simulation based on capacitance tomography was used to visualize the flow pattern and analyze the mixed characteristics. A gas top-blown agitation test rig was set up, the gas phase was air-selected, and the liquid phase was selected from synthetic heat-conducting oil. The top-blown stirring test process was measured and imaged by electrical capacitance tomography (ECT) equipment from ECT Instruments Ltd (UK). The MATLAB program was used to identify the mixing areas of the images to obtain the distribution of gas-liquid two-phase. The flow pattern of the gas-liquid mixing region was obtained. The chaotic detection of the gas-liquid mixing process was performed by the three-state test method;the images were processed by the counting box dimension-corrosion method to obtain the mixing uniformity time of gas-liquid flow. Results show that it is feasible to use the capacitance tomography technique to visualize the gas-liquid two-phase distribution. The uniformity time quantification of the gas-liquid mixing process is also achieved.

A compositional model for CO_(2) ooding including CO_(2) equilibria between water and oil using the Peng–Robinson equation of state with the Wong–Sandler mixing rule

This paper presents a three-dimensional, three-phase compositional model considering CO2 phase equilibrium between water and oil. In this model, CO2 is mutually soluble in aqueous and hydrocarbon phases, while other components, except water,exist in hydrocarbon phase. The Peng–Robinson(PR) equation of state and the Wong–Sandler mixing rule with non-random two-liquid parameters are used to calculate CO2 fugacity in the aqueous phase. One-dimensional and three-dimensional CO2 flooding examples show that a significant amount of injected CO2 is dissolved in water. Our simulation shows 7% of injected CO2 can be dissolved in the aqueous phase, which delays oil recovery by 4%. The gas rate predicted by the model is smaller than the conventional model as long as water is undersaturated by CO2, which can be considered as 'lost' in the aqueous phase. The model also predicts that the delayed oil can be recovered after the gas breakthrough, indicating that delayed oil is hard to recover in field applications. A three-dimensional example reveals that a highly stratified reservoir causes uneven displacement and serious CO2 breakthrough. If mobility control measures like water alternating gas are undertaken, the solubility e ects will be more pronounced than this example.

State Estimation Moving Window Gradient Iterative Algorithm for Bilinear Systems Using the Continuous Mixed p-norm Technique

This paper studies the parameter estimation problems of the nonlinear systems described by the bilinear state space models in the presence of disturbances.A bilinear state observer is designed for deriving identification algorithms to estimate the state variables using the input-output data.Based on the bilinear state observer,a novel gradient iterative algorithm is derived for estimating the parameters of the bilinear systems by means of the continuous mixed p-norm cost function.The gain at each iterative step adapts to the data quality so that the algorithm has good robustness to the noise disturbance.Furthermore,to improve the performance of the proposed algorithm,a dynamicmoving window is designed which can update the dynamical data by removing the oldest data and adding the newestmeasurement data.A numerical example of identification of bilinear systems is presented to validate the theoretical analysis.

Model Analysis of Influences of Aerosol Mixing State upon Its Optical Properties in East Asia

The air quality model system RAMS （Regional Atmospheric Modeling System）-CMAQ （Models-3 Com- munity Multi-scale Air Quality） coupled with an aerosol optical/radiative module was applied to investigate the impact of different aerosol mixing states （i.e., externally mixed, half externally and half internally mixed, and internally mixed） oil radiative forcing in East Asia. The simulation results show that the aerosol optical depth （AOD） generally increased when the aerosol mixing state changed from externally mixed to internally mixed, while the single scattering albedo （SSA） decreased. Therefore, the scattering and absorption proper- ties of aerosols can be significantly affected by the change of aerosol mixing states. Comparison of simulated and observed SSAs at five AERONET （Aerosol Robotic Network） sites suggests that SSA could be better estimated by considering aerosol particles to be internally mixed. Model analysis indicates that the impact of aerosol mixing state upon aerosol direct radiative forcing （DRF） is complex. Generally, the cooling effect of aerosols over East Asia are enhanced in the northern part of East Asia （Northern China, Korean peninsula, and the surrounding area of Japan） and are reduced in the southern part of East. Asia （Sichuan Basin and Southeast China） by internal mixing process, and the variation range can reach ＋5 W m 2. The analysis shows that the internal mixing between inorganic salt and dust is likely the main reason that the cooling effect strengthens. Conversely, the internal nfixture of anthropogenic aerosols, including sulfate, nitrate, ammonium, black carbon, and organic carbon, could obviously weaken the cooling effect.

A G^E/Equation of State Mixing Rule for Vapor-Liquid Equilibria

A new excess Gibbs free energy/equation of state type mixing 0rule was derived byremoving the infinite pressure boundary condition imposed by Wong and Sandler.The mixing rulewas extensively tested in terms of a comprehensive data base,consisting of 52 simple nonpolar-nonpolar,carbon dioxide containing,hydrocarbon-hydrocarbon,CFC,polar-polar,nonpolar-polarbinary and multicomponent systems.Focused on the complete predictive capability,a comparisonbetween the Wong-Sandler and the mixing rule proposed was conducted.The results indicate that thenew mixing rule is in general superior to the Wong-Sandler’s,and the binary interaction parameteras required by the latter is removed,which reduces computing effort and is reliable in predictions ofvapor-liquid equilibria from low pressures to high pressures.

New insight into prediction of phase behavior of natural gas hydrate by different cubic equations of state coupled with various mixing rules

Progress in hydrate thermodynamic study necessitates robust and fast models to be incorporated in reservoir simulation softwares. However, numerous models presented in the literature makes selection of the best,proper predictive model a cumbersome task. It is of industrial interest to make use of cubic equations of state(EOS) for modeling hydrate equilibria. In this regard, this study focuses on evaluation of three common EOSs including Peng–Robinson, Soave–Redlich–Kwong and Valderrama–Patel–Teja coupled with van der Waals and Platteeuw theory to predict hydrate P–T equilibrium of a real natural gas sample. Each EOS was accompanied with three mixing rules, including van der Waals(vd W),Avlonitis non-density dependent(ANDD) and general nonquadratic(GNQ). The prediction of cubic EOSs was in sufficient agreement with experimental data and with overall AARD% of less than unity. In addition, PR plus ANDD proved to be the most accurate model in this study for prediction of hydrate equilibria with AARD% of 0.166.It was observed that the accuracy of cubic EOSs studied in this paper depends on mixing rule coupled with them,especially at high-pressure conditions. Lastly, the present study does not include any adjustable parameter to be correlated with hydrate phase equilibrium data.

Extension of Huron-Vidal-type Mixing Rule to Three-parameter Harmens-Knapp Cubic Equation of State

In this paper was extended the HV-type mixing rules to Harmens-Knapp cubic equation state(HK CEOS). The new HV-type mixing rule with HK CEOS was tested for Vapor-liquid equilibrium(VLE) of different polar and nonpolar systems. The tested results are in good agreement with existing experimental data within a wide range of temperatures and pressures. In comparison with the VDW mixing rule, the new mixing rule gives much better predictions for the VLE of nonpolar and polar systems.

Solution for Energies and Mixing of Two 0^+ States in ^(10)He

Using results from various reactions that populate 10He, I conclude that the ground state has E2n = 1.07（7） MeV and the excited 0＋ state is in the region of 2.1-3.1 MeV. The amount of the （sd）2 component in the ground state is less than about 0.075.

Entangled State Representation for Four-Wave Mixing

We introduce the entangled state representation to describe the four-wave mixing.We find that the four- wave mixing operator,which engenders the correct input-output field transformation,has a natural representation in the entangled state representation.In this way,we see that the four-wave mixing process not only involves squeezing but also is an entanglement process.This analysis brings convenience to the calculation of quadrature-amplitude measurement for the output state of four-wave mixing process.

Ultraslow Propagation of Entangled State via Four-Wave Mixing in a Coupled Double Ouantum Well

An analytical method based on four-wave mixing （FWM） is here developed to study the generation of entangled state in an asymmetric semiconductor double quantum well structure. It is found that the maximally entangled state of two beams （the probe and four-wave mixing beams） can be achieved in an appropriate condition. Moreover, we also show that the two entangled beams propagate with ultraslow group velocity in the semiconductor medium. This investigation can be used for achieving the entangled beams in the semiconductor solid-state medium, which is much more practical than that in an atomic medium because of its flexible design and the wide adjustable parameters.

ERT Imaging of Gas-Liquid Mixing in Agitated Vessel

An investigation using Electrical Resistance Tomography （ERT） was carried out in order to characterize gas-liquid mixing in an agitated vessel. The experimental work was carried out in a 400 mm diameter agitated vessel that was fitted with four planes, 16 stainless steel electrodes. Agitation was carried out using the Lightnin Labmaster and Rushton turbine while conductivity data acquisition was carried out using the ITS P2000 ERT system. A Mathlab code was developed to construct a surface plot for gas hold-up from the ERT data. Various gas dispersion conditions such as flooded, loaded and fully dispersed were successfully characterized using the ERT technique.

THE MIXING OF GAS-LIQUID FLOW WITH VAPOR AND GAS-SOLID FLOW

In the industrial production, the mixing of gas-liquid flow with vapor and gas-solid flow is a very common problem. In the process of the mixing, solid particle-clusters will form, and will have steady radii when the effect of the gathering of particles is balanced withthat of the breaking of particle-clusters. Then, the population distribution function of size of particles per unit length per unit volume is introduced, and its governingequation is derived on the analogy of the molecular kinetic theory. Finally, when the gas flow is very slow, the expression of steady average radius of particle-clusters is obtained.

Extension of LCVM-type mixing rule to three-parameter equations of state for vapor-liquid equilibria of mixtures

In this paper, the LCVM mixing rule is extended to the multi-parameter equations of state by combining infi- nite-pressure and zero-pressure mixing rule models. The new LCVM-type mixing rule, coupled with Patel-Teja equation of state (EOS) is applied for vapor-liquid equilibria of different polar and non-polar systems in which the NRTL activity coefficient model is used to calculate the excess Gibbs free energy. The tested results agree well with existing experimental data within a wide range of temperatures and pressures. In comparison with the Van der Waals mixing rule, the new mixing rule gives much better corre- lations for the vapor-liquid equilibria of non-polar and polar systems.

One-year observation of the mixing states of oxygenated organics-containing single particles in Guangzhou,China

Oxygenated organic molecules(OOMs)play an important role in the formation of secondary organic aerosols(SOAs),but the mixing states of OOMs are still unclear.This study investigates the mixing states of OOM-containing single particles from the measurements taken using a single particle aerosol mass spectrometer in Guangzhou,China in 2022.Generally,the particle counts of OOM particles and the mass concentration of secondary organic carbon(SOC)exhibited similar temporal trends throughout the entire year.The OOM particles were consistently enriched in secondary ions,including ^(16)O^(−),^(26)CN^(−),^(46)NO_(2)^(−),^(62)NO_(3)^(−),and ^(97)HSO_(4)^(−).In contrast,the number fractions and diurnal patterns of OOM particles among the total detected particles showed similar distributions in August and October;however,the SOC ratios in fine particulate matter were quite different,suggesting that there were different mixing states of single-particle oxygenated organics.In addition,further classification results indicated that the OOM particles were more aged in October than August,even though the SOC ratios were higher in August.Furthermore,the distribution of hydrocarbon fragments exhibited a notable decrease from January to October,emphasizing the more aged state of the organics in October.In addition,the sharp increase in elemental carbon(EC)-OOM particles in the afternoon in October suggests the potential role of EC in the aging process of organics.Overall,in contrast to the bulk analysis of SOC mass concentration,the mixing states of the OOM particles provide insights into the formation process of SOAs in field studies.

Real-time,single-particle chemical composition,volatility and mixing state measurements of urban aerosol particles in southwest China

To investigate the volatility of atmospheric particulates and the evolution of other particulate properties(chemical composition,particle size distribution and mixing state)with temperature,a thermodenuder coupled with a single particle aerosol mass spectrometer was used to conduct continuous observations of atmospheric fine particles in Chengdu,southwest China.Because of their complex sources and secondary reaction processes,the average mass spectra of single particles contained a variety of chemical components(including organic,inorganic and metal species).When the temperature rose from room temperature to280℃,the relative areas of volatile and semi-volatile components decreased,while the relative areas of less or non-volatile components increased.Most(>80%)nitrate and sulfate existed in the form of NH_(4)NO_(3)and(NH_(4))_(2)SO_(4),and their volatilization temperatures were50–100℃and 150–280℃,respectively.The contribution of biomass burning(BB)and vehicle emission(VE)particles increased significantly at 280℃,which emphasized the important role of regional biomass burning and local motor vehicle emissions to the core of particles.With the increase in temperature,the particle size of the particles coated with volatile or semi-volatile components was reduced,and their mixing with secondary inorganic components was significantly weakened.The formation of K-nitrate(KNO_(3))and K-sulfate(KSO_(4))particles was dominated by liquid-phase processes and photochemical reactions,respectively.Reducing KNO_(3)and BB particles is the key to improving visibility.These new results are helpful towards better understanding the initial sources,pollution formation mechanisms and climatic effects of fine particulate matter in this megacity in southwest China.

Mixing states and secondary formation processes of organic nitrogen-containing single particles in Guangzhou,China

Organic nitrogen(ON)compounds play a significant role in the light absorption of brown carbon and the formation of organic aerosols,however,the mixing state,secondary formation processes,and influencing factors of ON compounds are still unclear.This paper reports on the mixing state of ON-containing particles based on measurements obtained using a highperformance single particle aerosol mass spectrometer in January 2020 in Guangzhou.The ON-containing particles accounted for 21% of the total detected single particles,and the particle count and number fraction of the ON-containing particles were two times higher at night than during the day.The prominent increase in the content of ON-containing particles with the enhancement of NO_xmainly occurred at night,and accompanied by high relative humidity and nitrate,which were associated with heterogeneous reactions between organics and gaseous NO_(x)and/or NO_(3)radical.The synchronous decreases in ON-containing particles and the mass absorption coefficient of water-soluble extracts at 365 nm in the afternoon may be associated with photo-bleaching of the ON species in the particles.In addition,the positive matrix factorization analysis found five factors dominated the formation processes of ON particles,and the nitrate factor(33%)mainly contributed to the production of ON particles at night.The results of this study provide unique insights into the mixing states and secondary formation processes of the ON-containing particles.

Teleportations of Mixed States and Multipartite Quantum States

In this paper, we propose a protocol to deterministically teleport an unknown mixed state of qubit by utilizing a maximally bipartite entangled state of qubits as quantum channel. Ira non-maximally entangled bipartite pure state is employed as quantum channel, the unknown mixed quantum state of qubit can be teleported with 1 -√ 1- C^2 probability, where C is the concurrence of the quantum channel. The protocol can also be generalized to teleport a mixed state of qudit or a multipartite mixed state. More important purpose is that, on the basis of the protocol, the teleportation of an arbitrary multipartite （pure or mixed） quantum state can be decomposed into the teleportation of each subsystem by employing separate entangled states as quantum channels. In the case of deterministic teleportation, Bob only needs to perform unitary transformations on his single particles in order to recover the initial teleported multipartite quantum state.

Entanglement dynamics of a moving multi-photon Jaynes-Cummings model in mixed states

Using the algebraic dynamical method, the entanglement dynamics of an atom-field bipartite system in a mixed state is investigated. The atomic center-of-mass motion and the field-mode structure are also included in this system. We find that the values of the detuning and the average photon number are larger, the amplitude of the entanglement is smaller, but its period does not increase accordingly. Moreover, with the increase of the field-mode structure parameter and the transition photon number, the amplitude of the entanglement varies slightly while the oscillation becomes more and more fast. Interestingly, a damping evolution of the entanglement appears when both the detuning and the atomic motion are considered simultaneously.

Mixed Symmetry Isomeric States in Nuclei

Mixed symmetry states are studied in the framework of the neutron-proton interacting boson model. It is found that some of the mixed symmetry states with moderate high spins change very fast with respect to the Majorana interaction. Under certain conditions, they become the yrast state or yrare state. These states are difficult to decay and become very stable. This study suggests that a possible new mode of isomers may exist due to the special nature in their proton and neutron degrees of freedom.

Mixed H_2/H_∞ State Feedback Attitude Control of Microsatellite Based on Extended LMI Method

For the appearance of the additive perturbation of controller gain when the controller parameter has minute adjustment at the initial running stage of system,to avoid the adverse effects,this paper investigates the mixed H_2/H_∞ state feedback attitude control problem of microsatellite based on extended LMI method.Firstly,the microsatellite attitude control system is established and transformed into corresponding state space form.Then,without the equivalence restriction of the two Lyapunov variables of H_2 and H∞performance,this paper introduces additional variables to design the mixed H_2/H_∞ control method based on LMI which can also reduce the conservatives.Finally,numerical simulations are analyzed to show that the proposed method can make the satellite stable within 20 s whether there is additive perturbation of the controller gain or not.The comparative analysis of the simulation results between extended LMI method and traditional LMI method also demonstrates the effectiveness and feasibility of the proposed method in this paper.