THE SOLID SOLUTION PHASE DIAGRAM OF THE MIXTURE OF ORTHO- AND PARACHLOROTOLUENES

The complete miscible solid solution with a minimum freezing point (-50.75℃; 26.88% para-) of the ortho- and para-chlorotoluene has been proved in this paper by many methods as the thermal analysis method, the X-ray matter phase analysis, the fractional crystallized separation method and the solidified separation method of solid solution, and by the Fel'dman's experiential productivity formula compared with the theoretical productivity formula which was obtained from the solidified separation according to the solid solution phase diagram. Therefore, the international official conclusion of simple eutectic type phase diagram of ortho- and para-chlorotoluene mixture does not agree with the experimental facts.The powder diffraction files of ortho- and para-chlorotoluenes are given in this paper.     

INVESTIGATION OF THE MIDDLE REDOX PEAK OF POLYANILINE ON THE CYCLIC VOLTAMMOGRAM

The middle peak which appeared frequently on the voltammetric curves has been interpreted as the degradation of the polymer, according to the results of anion effect. When α-CD (α-cyclodextrin) was added in the acidic solution of aniline to form aniline-α-CD complex, the middle peak became even higher during electrochemical polymorization. This suggests that the middle peak is mot originated from cross-link or ortho-polymerization in aqueous acidic solution.     

PHASE EQUILIBRIUM FOR THE TERNARY SYSTEM VINYL CHLORIDE-CHLORINATED POLYETHYLENE-POLY(VINYL CHLORIDE)

Swelling capacity of vinyl chloride (VC) in chlorinated polyethylene (CPE) with 25—40 wt% Cl at temperature 30—57℃was studied and their relationships were correlated with Langmuir and Freundlich adsorption equations. A ternary phase diagram for VC-CPE-PVC was also established. In-situ polymerization conditions of CPE-g-VC were proposed and CPE content control was analyzed for the manufacturing process of CPE-g-VC graft product based on results of phase equilibrium study.     

THE INVESTIGATION OF METHANE OXIDATIVE COUPLING ON BaF_2-LaOF CATALYST

ＴＨＥＩＮＶＥＳＴＩＧＡＴＩＯＮＯＦＭＥＴＨＡＮＥＯＸＩＤＡＴＩＶＥＣＯＵＰＬＩＮＧＯＮＢａＦ＿２－ＬａＯＦＣＡＴＡＬＹＳＴ￥ＺｉＳｈｅｎｇＣＨＡＯ；ＸｉａｏＰｉｎｇＺＨＯＵ；ＨｕｉＬｉｎＷＡＮａｎｄＫｈｉＲｉＴＳＡＩ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅ...     

INVESTIGATION OF THE ACTIVE PHASE OF Ag_xSb_yO_z/SiO_2 CATALYST FOR THE CONDENSATION OF ISOBUTENE AND FORMALDEHYDE INTO ISOPRENE

Chemical Composition,surface distribution of the elements and crystal structure offresh and deactivated Ag_xSb_yO_z/SiO_2 catalysts were investigated investigated by X-ray photoelectronspectroscopy(XPS),scanning Auger microprobc(SAM),electron microdiffraction(EMD)and atomic absorption spectroscopy(AAS).From the experimental results that in-clude the activity evaluation of model catalyst Sb_2O_4/SiO_2 Which Shows the inertness ofSb_2O_4 in Prins reaction,it is reasonable to infer that the active phase ofAg_xSb_yO_z/SiO_2 catalyst for Prins condensation reaction seems to be cubic AgSbO_3.Thereason of the deactivation of the catalyst was discussed.It is suggested that silver componentseems to be unstable in this catalyst.     

THE VISCOELASTIC EFFECT ON THE FORMATION OF MESO-GLOBULAR PHASE OF DILUTE HETEROPOLYMER SOLUTIONS

Linear homopolymer chains in poor solvent exist either as individual crumpled single chain globules or asmacroscopic precipitate, depending on whether the solution is in the one- or the two-phase region. However, linearheteropolymer chains in dilute solution might be able to form stable mesoglobules made up of a limited number of chains ifthe degree of amphiphilicity of the chain is sufficiently high and the experimental conditions are appropriate. The self-assembly of block copolymers in a selective solvent is typical of such examples. In practice, the formation of stablemesoglobules can be directly related to the formation of novel polymeric nanopaticles in solution. In this article, we willaddress the formaton of mesoglobular phase not only on the basis of thermodynamics, but also from a kinetic point of view,which leads to the discussion of how viscoelasticity can affect the phase behavior of heteropolymer chains in dilute solution.The formation and stabilization of several different kinds of novel polymeric nanopedicles will be used to illustrate ourdiscussion.     

EQUILIBRIUM PHASE DIAGRAM OF THE SYSTEM NaAlSiO_4-KAlSiO_4-SiO_2-H_2O at P_(H_2O)=5kb

The phase relations of the undersaturated part of the system Ne-Ks-Q-H_2O at P_(H_2O) =5kb aredetermined in this paper, and the liquidus maximum (Ne_(37)Ks_(37)Q_(26), 715℃) on the field boundary betweenalkali-feldspar and nepheline was first found by the authors. In the system Ne-Ks at P_(H_2O) =5kb, thefact that the solidus intersects the nepheline-kalsilite solvus means that the field boundary between nephe-line and kalsilite extends from the side line and forms a "ternary" invariant point at Ne_(25)Ks_(51)Q_(24) and630℃. The paths of crystallization of K-rich liquids at high pressure can be applied to explain thecrystallization processes of natural alkali rocks which are rich in K_2O.     

A THEORETICAL INVESTIGATION ON THE STRUCTURE OF THREE-DIMENSIONAL MESOGEN

ＡＴＨＥＯＲＥＴＩＣＡＬＩＮＶＥＳＴＩＧＡＴＩＯＮＯＮＴＨＥＳＴＲＵＣＴＵＲＥＯＦＴＨＲＥＥ－ＤＩＭＥＮＳＩＯＮＡＬＭＥＳＯＧＥＮ￥ＦｕＪｉａｎｇＤＩＮＧ；ＬｉａｎｇＦｕＺＨＡＮＧ（ＣｈｅｎｇｄｕＩｎｓｔｉｔｕｔｅｏｆＯｒｇａｎｉｃＣｈｅｍｉｓｔｒｙ...     

AN INVESTIGATION ON THE LOW TEMPERATURE RELAXATION OF POLYETHERETHERKETONE

The temperature spectra of internal friction of polyetheretherketone (PEEK) are investigated from 130K to 250K with a multi-function torsion pendulum in the frequency range of 0.1 Hz to 5 Hz. A relaxation process, γrelaxation, appears in the temperature range of the measurement. Its relaxation time distribution in terms of a Gaussian distribution, and the relation between molecular motion mechanism and the distribution characteristic are discussed. The element process of γrelaxation is found to be a disordering one.     

NdCl_3-SrCl_2-LiCl三元体系相图的研究

本文借助于DTA与X射线结构分析研究了NdCl_3-SrCl_2-LiCl三元体系相图。发现该体系内有对应于NdCl_3、SrCl_3、LiCl和Sr_3NdCl_9的四个液相面、五条二次结晶线、一个三元低共熔点E(68.0wt％NdCl_3,1.5wt％SrCl_2,30.5wt％LiCl;433℃)和三元转熔点P(65.8wt％NdCl_3,5.0wt％SrCl_2,29.2wt％LiCl;471℃)。同时发现有一个固相下形成的不稳定化合物Y(423℃分解)。     

DEPENDENCE OF ACRYLONITRILE POLYMERIZATION KINETICS ON THE COMPOSITION OF POLYAMIDOXIME-THIOUREA SYSTEM

The polymerization of acrylonitrile (AN) initiated by polypropylene based-polyamidoxime (PPAO)-thiourea (TU) system was investigated at [TU]/[PPAO]>0.5 molar ratio. It shows that the variation of the concentrations of PPAO, thiourea and nitric acid does not exert an observable influence on the reaction rate. The overall rate of polymerization (R_p) isR_p = 2.07e~(-7,800/RT)[ AN]~(2.0)The zero order dependence on PPAO and thiourea concentrations and the lowest value of the collision frequence factor were considered to be a feature of the primary radical termination.     

CYCLIC VOLTAMMETRIC INVESTIGATION OF THE MICELLAR PHASE OF SODIUM DODECYL SULFATE IN AQUEOUS SOLUTIONS

ＣＹＣＬＩＣＶＯＬＴＡＭＭＥＴＲＩＣＩＮＶＥＳＴＩＧＡＴＩＯＮＯＦＴＨＥＭＩＣＥＬＬＡＲＰＨＡＳＥＯＦＳＯＤＩＵＭＤＯＤＥＣＹＬＳＵＬＦＡＴＥＩＮＡＱＵＥＯＵＳＳＯＬＵＴＩＯＮＳ￥ＣｈｕｎＳｈｅｎｇＭＯ；ＺｈｅｎＺｈｏｎｇＨＵＡＮＧ；ＭｉｎｇＨｕａＺ...     

EFFECT OF PROCESSING METHOD ON THE IMPACT STRENGTH OF POM/TPU/CaCO3 TERNARY COMPOSITES

Polyoxymethylene （POM）/elastomer/filler ternary composites were prepared, in which thermoplastic polyurethane （TPU） and inorganic filler, namely, CaCO3, were used to achieve balanced mechanical properties of POM. The dispersion and phase morphology of POM/elastomer/filler composites were found to depend largely on processing method, CaCO3 content in masterbatch and the filler size. Two processing methods were employed to prepare POM/elastomer/filler ternary composites. One is called the one-step method, in which elastomer and the filler directly melt blended with POM matrix. The other is called the two-step method, in which the elastomer and the filler were mixed to get masterbatch first, which was then melt blended with pure POM of different content. The effect of phase morphology and processing method on impact strength was investigated. It was found that the two-step method results in an increase in impact strength but not for the one-step method. Additionally, the impact strength of POM ternary composites decreases with the increase in the size of CaCO3 particles.     

INVESTIGATION ON MICROELECTRODES Ⅻ THE DETERMINATION OF THE INVERSE CURRENT IN THE PROCESSES OF STEADY-STATE OR QUASI-STEADY-STATE

A simple method for determining the inverse current of cyclic voltammetry inthe processes of steady-state or quasi-steady-state was presented. The experimental resultverified the theoretical relation or inverse and forward current at microelectrode. Their ratio isproportional to the square root of scan rate.     

AN INVESTIGATION OF THE DISPERSION OF CuCl ON γ-Al_2O_3 SURFACE AND THE ADSORPTION OF ETHYLENE ON CuCl/γ-Al_2O_3 AND OTHER SUPPORTED TRANSITION METAL SALTS

In this work we investigate the dispersion of CuCl on γ-Al_2O_3 surface and the adsorptionof ethylene on CuCl/γ-Al_2O_3. X-ray diffraction experiments and u.v. diffuse reflectancespectra have shown that CuCl is highly dispersed on γ-Al_2O_3 surface, very likely as a mono-layer. The maximun amount of dispersion of CuCl on γ-Al_2O_3 surface determined by X-ray quantitative phase analysis is 0.095 g CuCl/100 M~2 on γ-Al_2O_3. The adsorption ofethylene on dispersed CuCl can be conveniently studied by the temperature programed de-sorption (TPD) method and shown to be achieved readily at ambient temperature and nor-mal pressure. The ability of adsorption for ethylene on CuCl/γ-Al_2O_3 is greater by threeorders of magnitude than that on undispersed CuCl particles of comparable size. The max-imum molecular ratio of ethylene adsorbed to dispersed CuCl is 0.19 C_2H_4/Cu~ . The cu-prous ions of dispersed CuCl can form surface complex with molecules such as C_2H_4 or C_3H_6so long as the stereochemical conditions are satisfied. These results may provide additionalscientific basis for separating unsaturated molecules from saturated ones by CuCl/γ-Al_2O_3.     

STUDIES ON THE PHOTOPOLYMERIZATION OF ACRYLONITRILE INITIATED BY BENZOPHENONE-ANILINE SYSTEM

The photopolymerization of acrylonitrile initiated by benzophenone-aniline system wasstudied under the irradiation at 365 nm. From the kinetic data measured in dimethylforma-mide the kinetic equation was presented as R_p∞[benzophenone]~(0.32) [aniline]~(0.27) [acryloni-trile]~(1.1). The rate of polymerization for different amines was in the following sequence, i.e.N, N-dimethylaniline>N-methylaniline>aniline. The influence of the polarity of solventwas investigated, from which we proposed that the proton transfer took place in the intimateradical-ion pair state of the exciplex between benzophenone and aniline. Among the twokinds of radicals produced the anilino radical is responsible for the initiation.     

STUDIES ON THE KINETICS OF PHASE TRANSITIONS OF A MAIN CHAIN THERMOTROPIC POLYESTER

The kinetics of phase transitions including a transition between mesophases were studied for a main-chain thermotropic polyester by means of DSC and depolarizing transmittance techniques. The isothermal process of these transitions was found to be described by the Avrami equation to high conversions. The Avrami exponents n are about 2,4, 5.3 and 2.2 for liquid crystallization, transition between mesophases and crystallization from mesophase respectively. The liquid crystallization from isotropic liquid phase occurs at very low undercoolings with high transformation rate. This behavior is explained as the results of the smaller value of the surface free energy for mesophase than that for crystallites which is evidenced by the very weak temperature dependence of liquid crystallization rate.     

INVESTIGATION ON THE CONFORMATION OF THE MAIN-CHAIN NEMATIC POLYMER BY SMALL ANGLE X-RAY SCATTERING

The experimental investigation on the conformation of a thermotropic main-chain nematic polymer by small-angle X-ray scattering (SAXS) has been carried out. The average radius of gyration of the polymer has been determined in nematic and isotropic state respectively. The experiment shows that the boundary between domains is not sharp but diffuse, and the diffuse-boundary thickness of the polymer as a function of temperature has been given.     

AN INVESTIGATION OF THE PROBLEM OF OCCURRENCE OF THE ATMOSPHERIC TURBULENCE

Using the truncated-spectrum model of Burger's-Chao Jiping equation, in which thetemperature advection is involved, we investigated the role of three parameters (Ri number, Renumber, Pr number) in occurrence of turbulence. It is shown that the turbulence may oc-cur only in the case of Ri<0.25 and Rc>2π~2. If Pr is too small (Pr = 0.7 for the atmos-phere), then the turbulence may occur only in the case of introducing interaction betweenbasic field and perturbation field or adding "viscosity" to the model. It is emphasized thatthe temperature advection plays an important role in turbulence occurrence. On the parame-ter plane (Ri, Re), the atmospheric motion states can be divided into the O-region (basicstate), the P-region (periodic state), the T-region (chaotic state), and the T-P region (cha-otic-periodic transition state). In fact, this is appropriate. Finally, the physical reason of turbu-lence occurrence is discussed.     

AN ANALYSIS ON THE EQUIVALENCE OF THE EYE TO A SYSTEM WITH ABERRATION

Computed transfer functions for ε=0.60 and 0.75 annular pupils of 2.67 mm o.d. showthat absorption of the average spherical aberration of the eye is still incomplete but if theeye is so designed as to adjust its focal plane in order to achieve a best Strehl ratio, itwould show a transfer function approaching that of a diffraction limited system, i.e. the opticaldefect of the eye is overcompensated. However, it is argued that a varying amount offocusing adjustment of the eye is needed in order to account for the transfer function ofthe eye of different pupil sizes, though not always to the extent of achieving a best Strehlratio. Such a property of the eye is referred to variously as the antidefocusing, deblurringor contrast constancy phenomenon and, when operationally defined, this is equivalent to sayingthat the eye has a greater depth of focus than that defined for a physical system based upona fixed demodulation criterion. The signifi ance of the physiological depth of the eye isdiscussed.