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.

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.

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 16O−,26CN−,46NO2−,62NO3−,and 97HSO4−.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.

Effect of cOVID-19 lockdown on the characterization and mixing state of carbonaceous particles in the urban atmosphere of Liaocheng, the North China Plain

To investigate the effect of covID-19 control measures on aerosol chemistry,the chemical compositions,mixing states,and formation mechanisms of carbonaceous particles in the urban atmosphere of Liao-cheng in the North China Plain(NCP)were compared before and during the pandemic using a single particle aerosol mass spectrometry(SPAMS).The results showed that the concentrations of five air pollutants including PM2.5,PM1o,SO2,NO2,and cO decreased by 41.2%-71.5%during the pandemic compared to those before the pandemic,whereas O3 increased by 1.3 times during the pandemic because of the depressed titration of O3 and more favorable meteorological conditions.The count and percentage contribution of carbonaceous particles in the total detected particles were lower during the pandemic than those before the pandemic.The carbonaceous particles were dominated by elemental and organic carbon(ECOC,35.9%),followed by elemental carbon-aged(EC-aged,19.6%)and organic carbon-fresh(OC-fresh,13.5%)before the pandemic,while EC-aged(25.3%),ECOC(17.9%),and secondary ions-rich(SEC,17.8%)became the predominant species during the pandemic.The carbonaceous particle sizes during the pandemic showed a broader distribution than that before the pandemic,due to the condensation and coagulation of carbonaceous particles in the aging processes.The relative aerosol acidity(Rra)was smaller before the pandemic than that during the pandemic,indicating the more acidic particle aerosol during the pandemic closely related to the secondary species and relative humidity(RH).More than 95.0%and 86.0%of carbonaceous particles in the whole period were internally mixed with nitrate and sulfate,implying that most of the carbonaceous particles were associated with secondary oxidation during their formation processes.The diurnal variations of oxalate particles and correlation analyses suggested that oxalate particles before the pandemic were derived from aqueous oxidation driven by RH and liquid water content(LwC),while oxalate particles during the pandemic were originated from O3-dominatedphotochemical oxidation.

Real-time geochemistry of urban aerosol during a heavy dust episode by single-particle aerosol mass spectrometer: Spatio-temporal variability, mixing state and spectral distribution

A heavy dust episode occurred from May 3 to 8,2017 in China,with an influenced area exceeding 1.63 million km2.In this work,the mixing state of aerosols and their spectral distributions were simultaneously observed in the sand source region ofHohhot and the long-range dust transport regi on of Nanji ng by using a single-particle aerosol mass spectrometer(SPAMS).The duration time of this dust episode was 37-40 h in Hohhot and prolonged to 51-104 h in Nanjing.Totals of 336,135(Hohhot)and 235,840(Nanjing)particles in PM2.5 were successfully ionized to identify 10 main particle classes.During this episode,aerosol particles including OCEC(30.65%),K(22.42%),K-CN(17.03%),sodium(9.46%),heavy metal(8.96%),EC-sulfate(3.46%)and Al(3.22%)were prevailing in Hohhot and were dominated by EC-sulfate(22.26%),OCEC(15.21%),heavy metal(11.96%),K(13.68%),sodium(12.27%),Al(10.54%)and EC(9.02%)in Nanjing.The spectral distribution peaked at 0.66μm during the dust episode in Nanjing,0.12μm larger than the peak size in the non-dust episode.Strong signals at-62[NO3)and-61[HCO3]/-61[C5H]for aerosol particles were observed in Hohhot and Nanjing respectively.The proportions of K-CN,sodium,heavy mental,OCEC and EC-sulfate particles in the dust episode of Hohhot were 2.75,1.41,1.80,1.22 and 1.28 times as large as the values in the non-dust episode.For Nanjing,the fractions of EC-sulfate,EC,Al particles in the dust episode were 10.55,4.65 and 1.46 times higher than values in the non-dust episode.The proportions of EC-secondary and EC-nitate particles were found to decrease in the dust episode in the two regions.

Online single particle analysis of chemical composition and mixing state of crop straw burning particles： from laboratory study to field measurement

Fresh straw burning （SB） particles were generated in the laboratory by the combustion of rice straw and corn straw. The chemical composition and mixing state of the fresh SB particles were investigated by an Aerosol Time-of-Flight Mass Spectrometer （ATOFMS）. Based on the mass spectral patterns, the SB particles were clustered into four major types： Salt, Organic Carbon （OC）, Elemental Carbon （EC）, and internally mixed particles of EC and OC （EC-OC）. In addition, particles containing ash, polycyclic aromatic hydrocarbons, heavy metals or nicotine were also observed. Physical and chemical changes of the SB particles immediately after the emission were analyzed with highly time-resolved data. During the aging processes, the average particle size increased steadily. Freshly emitted organic compounds were gradu- ally oxidized to more oxygenated compounds in the OC- containing particles. Meanwhile, an important displace- ment reaction （2KCI＋ SO24- KzSO4 ＋ 2C1-） was observed. The marker ions for SB particles were optimized and applied to identify the SB particles in the ambient atmosphere. The fluctuation of the number fraction of ambient SB particles sorted by ATOFMS agrees well with that of water soluble K＋ measured by an online ion chromatography, demonstrating that the optimized marker ions could be good tracers for SB particles in field measurements.

Enhanced mixing state of black carbon with nitrate in single particles during haze periods in Zhengzhou, China

Black carbon(BC)plays an important role in air quality and climate change,which is closely associated with its mixing state and chemical compositions.In this work the mixing state of BC-containing single particles was investigated to explore the evolution process of ambient BC particles using a single particle aerosol mass spectrometer(SPAMS)in March 2018 in Zhengzhou,China.The BC-containing particles accounted for 61.4%of total detected ambient single particles and were classified into five types including BC-nitrate(BC-N,52.3%)as the most abundant species,followed by BC-nitrate-sulfate(BC-NS,22.4%),BCOC(16.8%),BC-fresh(BC-F,4.5%)and BC-sulfate particles(BC-S,4.0%).With enhancement of the ambient nitrate concentration,the relative peak area(RPA)of nitrate in BC-N and BC–NS particles both increased,yet only the number fraction(N_(f))of BC–N particles increased while the N_(f) of BC-NS particles decreased,suggesting that the enhanced mixing state of BC with nitrate was mainly due to the increase in the ambient nitrate mass concentration.In addition,the Nfof BC-N decreased from 65.3%to 28.4%as the absorbing Angstrom exponents(AAE)of e BC increased from 0.75 to 1.45,which indicated the reduction of light absorption ability of aged BC particles with the enhanced formation of BC-N particles.The results of this work indicated a change in the mixing state of BC particles due to the dominance of nitrate in PM_(2.5),which also influenced the optical properties of aged BC particles.

Characteristics and mixing state of S-rich particles in haze episodes in Beijing

Direct individual analysis using Scanning Electron Microscopy combined with online obscrv ation was conducted to examine the S-rich particles in PM2.5 of two typical polluted haze cpisodes in summer and winter from 2014 to 2015 in Beijing. Four major types of S-rich particles, including sccondary CaSO4 particles （mainly observed in summer）, S-rich mineral particles （SRM）, S-rich water droplets （SRW） and （C, O, S）-rich particles （COS） were identified. We lbund the differcnt typical morphologies and element distributions of S-rich particles and considered that （C, O, S）-rich parliclcs had two major mixing states in different seasons. On the basis of the S-rich particles＂ relative abundances. S concentrations and their relationships with PM2.5 as well as the seasonal comparison, wc revealed that the S-participated formation degrees of SRM and SRW would enhance with increasing PM2.5 concentration. Moreover, C-rich matter and sulfate had seasonally differcnt but significant impacts on the formation of COS.

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.

CONTINUOUS TIME MIXED STATE BRANCHING PROCESSES AND STOCHASTIC EQUATIONS

A continuous time and mixed state branching process is constructed by a scaling limit theorem of two-type Galton-Watson processes.The process can also be obtained by the pathwise unique solution to a stochastic equation system.From the stochastic equation system we derive the distribution of local jumps and give the exponential ergodicity in Wasserstein-type distances of the transition semigroup.Meanwhile,we study immigration structures associated with the process and prove the existence of the stationary distribution of the process with immigration.

Experimentally testing Hardy's theorem on nonlocality with entangled mixed states

Hardy＇s theorem on nonlocality has been verified by a series of experiments with two-qubit entangled pure states.However,in this paper we demonstrate the experimental test of the theorem by using the two-photon entangled mixed states.We first investigate the generic logic in Hardy＇s proof of nonlocality,which can be applied for arbitrary two-qubit mixed polarization entangled states and can be reduced naturally to the well-known logic tested successfully by the previous pure state experiments.Then,the optimized violations of locality for various experimental parameters are delivered by the numerical method.Finally,the logic argued above for testing Hardy＇s theorem on nonlocality is demonstrated experimentally by using the mixed entangled-photon pairs generated via pumping two type-I BBO crystals.Our experimental results shows that Hardy＇s proof of nonlocality can also be verified with two-qubit polarization entangled mixed states,with a violation of about 3.4 standard deviations.

Entanglement evolution of three-qubit mixed states in multipartite cavity-reservoir systems

We analyze the multipartite entanglement evolution of three-qubit mixed states composed of a GHZ state and a W state. For a composite system consisting of three cavities interacting with independent reservoirs, it is shown that the entanglement evolution is restricted by a set of monogamy relations. Furthermore, as quantified by the negativity, the entanglement dynamical property of the mixed entangled state of cavity photons is investigated. It is found that the three cavity photons can exhibit the phenomenon of entanglement sudden death （ESD）. However, compared with the evolution of a generalized three-qubit GHZ state which has the equal initial entanglement, the ESD time of mixed states is later than that of the pure state. Finally, we discuss the entanglement distribution in the multipartite system, and point out the intrinsic relation between the ESD of cavity photons and the entanglement sudden birth of reservoirs.

WEAK FORMULATION OF MIXED STATE EQUATION ANDBOUNDARY VALUE PROBLEM OF LAMINATEDCYLINDRICAL SHELL

Weak formulation of mixed state equations including boundary conditions are presented in a cylindrical coordinate system by introducing Hellinger-Reissner variational principle. Analytical solutions are obtained for laminated cylindrical shell by means of state space method. The present study extends and unifies the solution of laminated shells.

Fidelity between Gaussian mixed states with quantum state quadrature variances

In this paper, from the original definition of fidelity in a pure state, we first give a well-defined expansion fidelity between two Gaussian mixed states. It is related to the variances of output and input states in quantum information pro- cessing. It is convenient to quantify the quantum teleportation （quantum clone） experiment since the variances of the input （output） state are measurable. Furthermore, we also give a conclusion that the fidelity of a pure input state is smaller than the fidelity of a mixed input state in the same quantum information processing.

Wave Period Distributions in Non-Gaussian Mixed Sea States

The wave period probability densities in non-Gaussian mixed sea states are calculated by utilizing a transformed Gaussian process method. The transformation relating the non-Gaussian process and the original Gaussian process is obtained based on the equivalence of the level up-crossing rates of the two processes. A saddle point approximation procedure is applied for calculating the level up-crossing rates in this study. The accuracy and efficiency of the transformed Gaussian process method are validated by comparing the results predicted by using the method with those predicted by the Monte Carlo simulation method.

A note on local unitary equivalence of isotropic-like states

We consider the local unitary equivalence of a class of quantum states in a bipartite case and a multipartite case. The necessary and sufficient condition is presented. As special cases, the local unitary equivalent classes of isotropic state and Werner state are provided. Then we study the local unitary similar equivalence of this class of quantum states and analyze the necessary and sufficient condition.

Social Advantage with Mixed Entangled States

It has been extensively shown in past literature that Bayesian game theory and quantum non-locality have strong ties between them. Pure entangled states have been used, in both common and conflict interest games, to gain advantageous payoffs, both at the individual and social level. In this paper, we construct a game for a mixed entangled state such that this state gives higher payoffs than classically possible, both at the individual level and the social level. Also, we use the I-3322 inequality so that states that aren’t useful advice for the Bell-CHSH1 inequality can also be used. Finally, the measurement setting we use is a restricted social welfare strategy (given this particular state).

Strong decays of P-wave mixing heavy-light 1^+ states

Many P-wave mixing heavy-light 1^＋ states have not yet been discovered by experiment, while others have been discovered but without width information, or with large uncertainties on the widths. In this paper, the strong decays of the P-wave mixing heavy-light 1^＋ states D^0, D^±, D^±, B^0, B^±： and Bs are studied by the improved Bethe SMpeter （B-S） method with two conditions of mixing angle 0： one is 0 = 35.3°; the other is considering a correction to the mixing angle 0=35.3°＋θ1. Valuable predictions for the strong decay widths are obtained： F（D1^0）=232 MeV, r（D1^0）=21.5 MeV, F（D1^±）=232 MeV, F（D1^±）=21.5 MeV, F（Ds1^±）=0.0101 MeV,Г（Ds1^±l）=0.950 MeV, F（BГ^±＋）=263 MeV, F（B1^±=16.8 MeV, F（B′s1）=0.01987 MeV and F（B,1）=0.412 MeV. It is found that the decay widths of D~ and Bsl are very sensitive to the mixing angle. The results will provide theoretical assistance to future experiments.

Isospin and Symmetry Structure in ^(36)Ar

The interacting boson model-3(IBM-3) has been used to study the isospin excitation states and electromag-netic transitions for ^(36)Ar nucleus.The mixed symmetry states and superdeformed band at low spin are also analyzed.The theoretical calculations are in agreement with experimental data,and the ^(36)Ar is superdeformed rotational nucleusclose to the SU(3) limit.The present calcula,tions indicate that the 2_4^+ state is the lowest mixed symmetry state and thelowest isospin T=1 excitation state and at about 6.2 MeV,and the bandhead of superdeformed band is 0_2^+ state.