Calculation of electric field–temperature (E, T) phase diagram of a ferroelectric liquid crystal near the SmA–SmC_α~* transition

In this work we perform a theoretical calculation in order to reconstitute the （E-T） phase diagram of a chiral smectic liquid crystal in the vicinity of the SmA-SmCα＊ transition. This reconstruction is carried out on the basis of a thermo-dynamic calculation of the slope of the curve joining the SmC＊ domain and the unwound SmC＊. An empiric correction of the mean field term of Landau De-Gennes development is necessary to accomplish this reconstruction. Thereafter, an experimental validation is performed to verify our calculations.

Electro-optical properties and(E,F) phase diagram of fluorinated chiral smectic liquid crystals

Fluorinated smectic liquid crystals each with a biphenyl benzoate rigid core are investigated. Molecular structures of the studied compounds have difference only in fluorine position and the length of the carbon chain. Dielectric relaxation study and electro-optical measurements are carried out with the classical SSFLC geometry. The field-induced phase transitions are studied and the（E,T） phase diagram is established.

Ternary System of Fe-based Ionic Liquid,Ethanol and Water for Wet Flue Gas Desulfurization

Fe-based ionic liquid （Fe-IL） was synthesized by mixing FeCl3·6H2O and 1-butyl-3-methylimidazolium chloride [Bmim]C1 in this paper. The phase diagram of a ternary Fe-IL, ethanol and water system was investigated to construct a ternary desulfurization solution for wet flue gas desulfurization. The effects of flow rate and concentration of SO2, reaction temperature, pH and Fe-IL fraction in aqueous desulfurization solution on the desulfiariza- tion efficiency were investigated. The results shows that the best composition of ternary desulfurization solution of Fe-IL, ethanol and water is 1 ： 1.5 ： 3 by volume ratio, and pH should be controlled at 2.0. Under such conditions, a desulfurization rate greater than 90% could be obtained. The product of sulfuric acid had inhibition effect on the wet desulfurization process. With applying this new ternary desulfurization solution, not only the catalyst Fe-IL can be recycled and reused, but also the product sulfuric acid can be separated directly from the ternary desulfurization system.

SOLUBILITY CHARACTERISTICS OF GaAs IN Bi AND THEIR PHASE DIAGRAM

A modified liquid phase epitaxy apparatus for semiconductor materials was used to measure the solubility of GaAs in Bi.Two phase diagrams rich in Bi under H_2 and N_2 atmospheres were obtained according to the results of measurement.A new phenomenon,in which the parameter Q value(quantity of GaAs dissolved in Bi in fixed time/saturation quantitu,of GaAs in Bi)was different from each other at various temperatures and there existed a maxi- mum Q value at definite temperature,was observed.This phenomenon may be regarded as a common feature of a simple binary metallic system which has the phase diagram similar to that of Bi-GaAs.The difference observed from the dependence of Q values on temperature in both H_2 and N_2 atmospheres was discussed.

THERMODYNAMICS AND PHASE EQUILIBRIUM OF Cu－Y－O，Cu－Y－S，Cu－Y－O－S LIQUID SOLUTIONS

ＴＨＥＲＭＯＤＹＮＡＭＩＣＳＡＮＤＰＨＡＳＥＥＱＵＩＬＩＢＲＩＵＭＯＦＣｕ－Ｙ－Ｏ，Ｃｕ－Ｙ－Ｓ，Ｃｕ－Ｙ－Ｏ－ＳＬＩＱＵＩＤＳＯＬＵＴＩＯＮＳ￥Ｄｕ，Ｔｉｎｇ；Ｌｉ，Ｇｕｏｄｏｎｇ（ＣｅｎｔｒａｌＩｒｏｎａｎｄＳｔｅｅｌＲｅｓｅａｒｃｈｉｎｓｔｉｔ...

Recent progress of nuclear liquid gas phase transition

Recent progress on nuclear liquid gas phase transition (LGPT) has been reviewed, especially for the signals of LGPT in heavy ion collisions. These signals include the power-law charge distribution, cluster emission rate, nuclear Zipf law, bimodality, the largest fluctuation of the fragments, Δ-scaling, caloric curve, phase coexis- tence diagram, critical temperature, critical exponent analysis, negative specific heat capacity and spinodal instability etc. The systematic works of the authors on experimental and theoretical LGPT are also introduced.

Method of Phase Diagrams for the Analysis of Seism-Acoustical Spatial-Time Monitoring Data in Oil Wells

Experimental and theoretical studies of the mechanisms of vibration stimulation of oil recovery in watered fields lead to the conclusion that resonance oscillations develop in fractured-block formations. These oscillations, caused by weak but long-lasting and frequency-stable influences, create the conditions for ultrasonic wave’s generation in the layers, which are capable of destroying thickened oil membranes in reservoir cracks. For fractured-porous reservoirs in the process of exploitation by the method of water high-pressure oil displacement, the possibility of intensifying ultrasonic vibrations can have an important technological significance. Even a very weak ultrasound can destroy, over a long period of time, the viscous oil membranes formed in the cracks between the blocks, which can be the reason for lowering the permeability of the layers and increasing the oil recovery. To describe these effects, it is necessary to consider the wave process in a hierarchically blocky environment and theoretically simulate the mechanism of the appearance of self-oscillations under the action of relaxation shear stresses. For the analysis of seism acoustic response in time on fixed intervals along the borehole an algorithm of phase diagrams of the state of many-phase medium is suggested.

Thermodynamics and Phase Equilibrium of Cu－Ce－O，Cu－Ce－S，Cu－Ce－O－S Liquid Solutions

Thermodynamics of Cu-Ce-O,Cu-Ce-S and Cu-Ce-0-S solutions at 1200℃ were studied by using solid electrolyte cell and chemical equilibrium method.The equilibrium constant of deoxidation,desulfurization and deoxysulfurization by Ce,the Gibbs standard reaction free energies of the formation of Ce_2O_3,CeS and Ce_2O_2S in Cu-base solution,activity interaction coefficients of S and Ce,temperature dependence of standard reaction free energy of solution of Ce in Cu,self-interaction coefficients of Ce in liquid Cu have been obtained.The phase precipitation diagram for Cu-CeS-O system has been plotted.The thermodynamic condition of the existence of Ce_2O_3,CeS and Ce_2O_2S in liquid Cu has been determined.It provides the basis for predicting the sequence and the type of equilibrium inclusions of Ce formed in Cu-base solution.

Comparison of Different Cartridges of Solid Phase Extraction for Determination of Polyphenols in Tobacco by UPLC/MS/MS and Multivariate Analysis

The comparison of solid phase extraction（SPE） for the preconcentration and isolation of polyphenols in tobacco samples was carried out by ultra-high performance liquid chromatography/tandem mass spectrometry （UPLC/MS/MS） and multivariate analysis.Several adsorbing materials of SPE（C18,NH2,SAX and OASIS） were investigated.It was found that the C18 and OASIS cartridges can not only speed up the purification process,but also simplify the SPE operation.A UPLC/MS/MS was used for the determination of polyphenols in tobacco samples after purification.All analytes were separated and determined in 2min.The limit of detection was 0.05 ng/mL.Cluster analysis（CA） and principal component analysis（PCA） were used for the analysis of 4 varieties（flue-cured tobacco,oriental tobacco,sun-cured tobacco and burley） in order to interpret the effect of planting and machining process on the concentration of polyphenols.The different types of tobacco samples could be easily clustered by CA.PCA on the chemical composition of tobacco resulted in two principal components（PCs） that take 84.2% of the total variance.The PCA and CA indicate that the polyphenols can be used for distinguishing tobacco types.

STUDIES ON CRITICAL CONCENTRATION OF LIQUID CRYSTALLINE ETHYLCELLULOSE

Critical concentrations of lyotropic liquid crystalline ethylcellulose in more than ten solvents were determined using both Abbe refractometer and polarized microscopy. Critical concentration C-crit of forming Liquid crystal phase decreased with increasing solubility parameter delta of solvent until approaching the delta of polymer. Although the alcohols used as solvents had the same variation rule, the critical concentration values of their solutions were much higher, due to their excessive large hydrogen bond component of delta. The experiments of using mixed solvents which showed good linear relation between C-crit and delta also proved this rule. A technique of Transmission Optical Analysis was first used to estimate the concentration dependence of critical phase transition temperature T-crit of EC, and a T-C phase diagram could be drawn.

Phase Behavior of the Ternary Solution Involving Rodlike and Random Coil Polymers

The present paper covers the phase behavior of poly(pbenzamide)(PBA)/Nylon 6/H 2SO 4 and poly(pphenylene terephthalamide) (PPTA)/Nylon 6/H 2SO 4 systems. The transition temperatures detected by the Depolarized Light Intensity measurements were used to construct the phase diagram in which the influence of temperature was shown. The enhanced depolarized light intensity observed in the ternary system suggests that the coil polymer chains may tend to be extended and contribute to the overall anisotropy of the liquid crystal phase.

Design and development of the self-assemble Cu-Fe base composites

The Cu-Fe base alloys with liquid immiscible were prepared by gas atomization technique and conventional solidification process, the self-assemble composite microstructures in powders and bulk materials can be obtained under gravity conditions, respectively, and the minor liquid phase always forms the center of composite microstructure. It is shown that the formation of the core-type macroscopic morphology is strongly connected with the existence of a stable miscibility gap of the liquid phase in the Cu-Fe base alloys. This result can be explained by a mechanism that the minor droplets as the second phase are forced to move into the thermal center due to Marangoni motion, which is caused by the temperature dependence of interfacial energy between two liquid phases.

Studies on Room Temperature Ionic Liquid Prepared from InCl_3-MBIC

The phase diagram of InCl3-MBIC was constructed by DSC method. A clear, colorless and mobile ionic liquid was obtained and liquid down to 258 K. Both Raman scattering and ab initio calculations indicate that InCl4- is the predominant anion.

First Binary Mixture Ionic Liquids Containing EMIMBr and IM

A new series of binary mixture ionic liquids comprising 1-ethyl-3-methylimidozalium bromide (EMIMBr) and imidazole (IM) have been synthesized. The melting points of the ionic liquids vary with the different content of IM while they still keep satisfactory conductivity and viscosity. According to the analysis of its phase diagram, the eutectic point is about 16.5C with the mass percentage of IM 29%.

联合UPLC-QTOF-MS与HS-SPME-GC-MS测定赣南脐橙果肉化学成分

采用超高效液相色谱-四极杆飞行时间串联质谱技术,在37 min内鉴定脐橙果肉中的148种非挥发性有机物,分别为黄酮类、有机酸类、氨基酸类和其他植物化学成分。采用顶空固相微萃取结合气相色谱-质谱联用技术,研究赣南地区4个主产区瑞金、信丰、安远和南康脐橙果肉中挥发性有机物,总共鉴定挥发性有机化合物97种,包括酯类、醇类、醛类和萜烯类化合物。研究结果为进一步分析赣南地区的脐橙果肉物质提供详细数据,对进一步研究赣南脐橙物质基础具有一定指导意义。

A general thermodynamic analysis and treatment of phases and components in the analysis of phase assemblages in multicomponent systems

Systematic thermodynamic analysis reveals that an essential condition for the thermodynamically valid chemographic projec-tions proposed by Greenwood is completely excessive.In other words,the phases or components from which the projection is made need not be pure,nor have their chemical potentials fixed over the whole chemographic diagram.To facilitate the analy-sis of phase assemblages in multicomponent systems,all phases and components in the system are divided into internal and external ones in terms of their thermodynamic features and roles,where the external phases are those common to all assem-blages in the system,and the external components include excess components and the components whose chemical potentials(or relevant intensive properties of components) are used to define the thermodynamic conditions of the system.This general classification overcomes the difficulties and defects in the previous classifications,and is easier to use than the previous ones.According to the above classification,the phase rule is transformed into a new form.This leads to two findings:(1) the degree of freedom of the system under the given conditions is only determined by the internal components and phases;(2) different external phases can be identified conveniently according to the conditions of the system before knowing the real phase rela-tions.Based on the above results,a simple but general approach is proposed for the treatment of phases and components:all external phases and components can be eliminated from the system without affecting the phase relations,where the external components can be eliminated by appropriate chemographic projections.The projections have no restriction on the states of the phases or the chemical potentials of components from which the projections are made.The present work can give a unified ex-planation of the previous treatments of phases and components in the analysis of phase assemblages under various specific conditions.It helps to avoid potential misunderstandings or errors in the topological analysis of phase relations.

基于GC×GC-TOF/MS初探茶、酒风味融合

茶酒是茶和酒结合的产物,成分组成及风味复杂,研究采用液液萃取和顶空固相微萃取结合全二维气相色谱-飞行时间质谱联用(comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry,GC×GC-TOF/MS)分析茶酒及其基酒的挥发性成分组成和相对含量。结果显示,茶酒中分析鉴定出366种挥发性组分,包括酯类化合物136种,醇类39种,醛酮类48种,酸及酸酐30种,酚类4种,呋喃类16种,含氮化合物31种,萜烯类7种,含硫化合物6种,醚类7种,烷类14种,其他化合物28种。液液萃取和顶空固相微萃取结合GC×GC-TOF/MS的分析方法可快速、全面分析鉴定茶酒中各类挥发性组分,结果对于明确茶酒物质基础具有重要意义,为茶酒的风味体系、风味融合和健康属性研究提供了科学支撑。

Thermodynamics of spin-1/2 Kagomé Heisenberg antiferromagnet:algebraic paramagnetic liquid and finite-temperature phase diagram

Quantum fluctuations from frustration can trigger quantum spin liquids(QSLs) at zero temperature.However, it is unclear how thermal fluctuations affect a QSL. We employ state-of-the-art tensor network-based methods to explore the ground state and thermodynamic properties of the spin-1=2 kagomé Heisenberg antiferromagnet(KHA). Its ground state is shown to be consistent with a gapless QSL by observing the absence of zero-magnetization plateau as well as the algebraic behaviors of susceptibility and specific heat at low temperatures, respectively. We show that there exists an algebraic paramagnetic liquid(APL) that possesses both the paramagnetic properties and the algebraic behaviors inherited from the QSL. The APL is induced under the interplay between quantum fluctuations from geometrical frustration and thermal fluctuations. By studying the temperature-dependent behaviors of specific heat and magnetic susceptibility, a finite-temperature phase diagram in a magnetic field is suggested, where various phases are identified. This present study gains useful insight into the thermodynamic properties of the spin-1/2 KHA with or without a magnetic field and is helpful for relevant experimental studies.

Three-Dimensional Representation of Geochemical Data from a Multidimensional Compositional Space

Systems described by a wide set of variables, like rock compositions, may be often modeled by a reduced set of components, like minerals, that can be represented in diagrams in two or three dimensions. This paper deals with an original algorithm that allows the representation of compositional data in tetrahedral diagrams, provided that they can be recast on the basis of four end members. The algorithm is based on the orthogonal projection of a given point belonging to Rn to the 3D-space through four Rn points representing the compositions of suitable end members. The algorithm is applied to the assessment of mass balance problems (in weight% or molar basis) as well as to the identification of the geochemical imprint revealed by isotope ratios in igneous rock suites. The fields of possible applications are by far wider, encompassing all problems of comprehensive data representation from a multidimensional space to a bi-dimensional plot.

固–液相变含水率区间松散土石体中细粒组分抗剪特性试验

松散土石体在泥水作用下易引发地质灾害,其中细粒组分在高含水率下的抗剪性能骤然劣化是触发相变失稳的重要因素之一。基于环剪试验,对三峡库区某滑坡松散土石体试样设计试验方案,研究细组构由软塑~流塑发展的固-液相变全过程抗剪特性演化规律。结果表明:松散土石体试样为粗细组分二元特征较强的级配不良土体介质,其中,细粒组分在原状干密度条件下的饱和含水率为23.6%,液塑限分别为27.2和18.1,据此选定含水率23.6%~29.0%范围中的5个取值制定试验方案,可完整覆盖细粒组分的软塑~流塑相变;含水率为25.0%、26.0%和27.0%时,试样处软塑状态,在低法向压力下均可顺利开展环剪试验;其中,含水率25.0%试样恰进入软塑态,较含水率23.6%试样的峰值和残余内摩擦角分别降低23.5%和18.6%,峰值和残余黏聚力均降低超过80%。含水率为28.0%和29.0%时,试样已处于流塑状态,仅在无法向压力时可顺利开展环剪试验,且抗剪强度极低,其物理意义贴近于高黏稠泥浆的黏滞性;根据试样的黏聚力c在进入软塑状态时基本丧失,而内摩擦角φ表现为在软塑区间随含水率增加而逐步降低,进而触及液限骤然丧失的特性分析,c和φ劣化过程异步;经单元体受力模式和概化分析认为,相变前软塑状态试样静止侧压力系数K0的激增缓解了φ值的大幅骤降。