MICELLAR CATALYSIS-THE KINETICS OF Ni(Ⅱ)AND PYRIDYLAZO DYES COMPLEX FORMATION IN THE PRESENCE OF SODIUM DODECYL SULFATE MICELLES

By means of the Stopped—Flow Spectrophotometry,the kinetics of the reactions betweennickel(Ⅱ)and the ligand 5—bromopyridylazo diethylaminophenol(5-BrPADAP)and 3,5—dibromopyridylazo diethylaminophenol(3,5—2BrPADAP)have been investigated in themicellar solution of sodium dodecyl sulfate(SDS).The reaction rate(compared with thatmeasured in aqueous solution for the same Ni~(2+)concentration)was enhanced up to a factorof 400.Kinetic analysis indicates that the rate enhancement can be explained in terms of theconcentration effect of the micelles on the rcactants(i.e.partitioning coefficient effects).Aquantitative expression for the rate enhancement is derived,using the psudo—phase modeland Berezin’s original micellar-catalysis coneepts.The influenccs of hydrophobic character-istics of ligands on the micellar-catalysis effect have been studied also.     

IMFLUEHCE OF EDTA ON THE VOLTAMMETRIC RESPONSES OF IRONAND THE PITTING EFFECT OF CI－IOH IN BEUTRAL SODIUM SULFATE SOLUTION

ＩＭＦＬＵＥＨＣＥＯＦＥＤＴＡＯＮＴＨＥＶＯＬＴＡＭＭＥＴＲＩＣＲＥＳＰＯＮＳＥＳＯＦＩＲＯＮＡＮＤＴＨＥＰＩＴＴＩＮＧＥＦＦＥＣＴＯＦＣＩ－ＩＯＨＩＮＢＥＵＴＲＡＬＳＯＤＩＵＭＳＵＬＦＡＴＥＳＯＬＵＴＩＯＮＱｉａｎｇＳＨＥＨ；ＳｈｅｎＨａｏＣＨＥＮ...     

STUDIES ON BIO-ANTIOXIDANTS——PROOXIDATION OF VITAMIN E ON THE AUTOXIDATION OF LINOLEIC ACID IN SODIUM DODECYL SULFATE MICELLES

The reaction of vitamin E (α-tocopherol) with linoleic acid containing peroxidized linoleic acid has been studied. No significant reaction was found in ethanol solution, whereas in sodium dodecyl sulfate micelles vitamin E reacted rapidly with peroxidized linoleic acid, and thereby induced the peroxidation of linoleic acid, leading to oxygen absorption. The reaction kinetics was studied in detail by u. v. spectroscopy, HPLC and ESR spectroscopy. It was found that the main product was α-tocopherone with α-tocopheroxy radical as the reaction intermediate. A mechanism involving two consecutive bimolecular reactions between peroxidized linoleic acid and a-tocopherol and between peroxidized linoleic acid and a-tocopheroxy radical, with rate constant 2.93 and 6.21 mol/L-1s-1 respectively is proposed. The micellar effect on the reaction is discussed.     

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.     

STUDIES ON DERIVATIVE FLUORIMETRY Ⅲ. DETERMINATION OF TRACE AMOUNT OF TERBIUM IN THE PRESENCE OF SODIUM DODECYL SULFONATE

The derivative fluorimetric characteristics of Tb—SDS and Tb—SDS—phenanthroline systems have been studied. The optimum conditions were obtained. The 2nd—derivative spectrofluorimetric method in the systems has been applied to the determination of trace amounts of terbium, in rare earth ore and their oxides. The results are satisfactory.     

THE PROCESS OF THE EMULSIFIER-FREE POLYMERIZATION IN THE PRESENCE OF BARIUM SULFATE POWDER

The process of emulsifier-free copolymerization of the Styrene-Butyl Acrylate-K_sS_sO_s-water in thepresence of Barium Sulfate(BS)powder was investigated under varied conditions within the range of BSpowder quantity,initiator concentration and reaction temperature.Experimental results showed thatthe rate of polymerization is proportional to 0.3-power of the BS quantity and 1.3-power of theinitiator concentration.There is a linear relationship of 2/3-power for the conversion and time.Aprocess for the polymerization is propose to explain the experimental results.     

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.     

SOAPLESS EMULSION COPOLYMERIZATION IN THE PRESENCE OF BARIUM SULFATE POWDER

To investigate soapless emulsion copolymerization in the presence of a solid phase,copolymerization experiments were carried out for the styrene-butyl acrylate-K_2S_2O_8-watersystem by using barium sulfate powder,which is assumed to be chemically inert.Reactionconditions were varied with respect to barium sulfate powder quantity,initiator concen-tration and temperature.These factors were investigated with respect to the effect onreaction rate and conversion,polymer particle number and diameter,and latex stability.     

STUDIES ON THE ANIONIC SPECIES OF SODIUM ALUMINATE SOLUTIONS OF LOW CAUSTIC RATIOS

ＳＴＵＤＩＥＳＯＮＴＨＥＡＮＩＯＮＩＣＳＰＥＣＩＥＳＯＦＳＯＤＩＵＭＡＬＵＭＩＮＡＴＥＳＯＬＵＴＩＯＮＳＯＦＬＯＷＣＡＵＳＴＩＣＲＡＴＩＯＳ￥ＹｉＬｉｎＣＡＯ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＨｅｎａｎＮｏｒｍａｌＵｎｉｖｅｒｓｉｔｙ，Ｘ...     

DETERMINATION OF PHASE INVERSION POINT IN THE EMULSIFICATION OF POLYMERS

Polymer Physics Laboratory, Institute of Chemistry,The Chinese Academy of Sciences, Beijing 100080, China     

THE RELATION BETWEEN THE DIMENSIONS OF BOUNDARY AND PHASE BOUNDARY IN ISOBARIC PHASE DIAGRAMS

The relation between the dimensions of boundary and phase boundary in isobaric phase diagrams has been proved theoretically in this paper.     

EFFECTS OF SODIUM SALICYLATE ON THE FEBRILE RESPONSE AND INCREASED LEVELS OF CYCLIC AMP IN CEREBRO-SPINAL FLUID DURING ENDOGENOUS PYROGEN-INDUCED FEVER IN RABBITS

To further evaluate the causality between endogenous pyrogen (EP)-induced fever andcyclic adenosine- 3', 5'- monophosphate (cyclic AMP) level. the effects of sodium salicylate(SS) on the febrile response and increased levels of cyclic AMP in both cerebrospinal fluid(c.s.f.) and plasma during EP- induced fever in rabbits were observed. The results suggestthat cyclic AMP is probably involved in the central mediation of EP-induced fever and thatincreased concentration of cyclic AMP in c.s.f. associated with EP- induced fever is not theresult of temperature elevation but appears to be caused by the increased synthesis in the cen-tral nervous system. In addition it is confirmed that blood is impossibly a contributorysource of increased cyclic AMP in c.s.f. during EP fever, and that SS may act subsequentto the increase in cyclic AMP.     

PHOTOPOLYMERIZATION IN THE MICELLAR SYSTEMS Ⅳ THE PHOTOSENSITIZATION EFFECTS OF THE BENZOPHENONES WITH DIFFERENT CHARGE IN IONIC MICELLAR SYSTEMS*

The photosensitization effects of the benzophenone derivatives having different charges, such as cationic BP(BP—CH_2—N~+ (C_2H_5)_3Br~-) (PKT-1), anionic BP(BP—COONa) and the neutral BP in the various ionic micellar systems were studied. From the photopolymerization of MMA initiated by the various BP/TEA in different micellar systems, the results obtained show that the polymerization rate is in the order of PKT-1>BP>BP—COONa in the SDS anionic micelle. On the contrary, the order changes to BP—COONa>BP>PKT-1 in the CTAB cationic mieelle, and to BP—COONa≈PKT-1>BP in the PKT-3 functional micelle. It is noteworthy that the PKT-1/SDS system is more efficient with its quantum yield more than 50 times compared with that of simple BP/H_2O system.     

STUDIES ON THE ACTIVITY COEFFICIENTS OF NON-ELECTROLYES IN AQUEOUS SALT SOLUTIONS Ⅲ. THR EFFECTS OF SALTS OF FATTY ACIDS ON THE SOLUBILITIES OF CAPROIC ACID IN WATER

The solubilities of caproic acid in aqueous solutions of sodium salts of fivefatty acids (C_1 to C_5) have been measured at 25℃. All these salts increase thesolubilities of caproic acid. The reason for salting-in is due to partial displacement of the salt by thecaproic acid producing a new acid. But the new acid may distribute itself betweenthe aqueous salt, solution phase and the caproic acid phase thus rendering the actualsolubilities less than the calculated values.     

PRELIMINARY EXAMINATION OF THE CONCURRENT SYNTHESIS OF METHANOL IN SLURRY PHASE

本文报道了ｌ升浆液搅拌釜内一体化甲醇合成反应过程中涉及的甲醇连续羰基化、甲酸甲酯氢解和低温甲醇合成反应的初步考察结果。     

THE DETERMINATION OF GLUCOSE IN URINE BY USING CYCLIC VOLTAMMETRY

ＴＨＥＤＥＴＥＲＭＩＮＡＴＩＯＮＯＦＧＬＵＣＯＳＥＩＮＵＲＩＮＥＢＹＵＳＩＮＧＣＹＣＬＩＣＶＯＬＴＡＭＭＥＴＲＹ￥ＺｈｅｎｇＹｕＺＨＯＵ；ＣａｎＺｈｕＧＡＯ；ＱｉｎｇＣｕｎＺＨＵ；ＦｕＹｅＧＡＯ；ＦａｎＺｈｅｎＫＯＮＧ（ＣｈｅｍｉｓｔｒｙＤｅｐａｒｔ...     

STUDIES ON THE ACTIVITY COEFFICIENTS OF NONELECTROLYTES IN AQUEOUS SALT SOLUTIONS——Ⅱ. THE EFFECTS OF SALTS OF FATTY ACIDS AND QUATERNARY AMMONIUM SALTS ON THE SOLUBILITIES OF NAPHTHALENE IN WATER

On the assumption that the salt effect (salting-out or salting-in) representsthe balance of the electrostatic effect between the ion and the water dipole andthe dispersion effect between ion and nonelectrolyte molecule, the solubilitiesof n-valeric acid in five cobaltammimes were studied and reported in article Ⅰof this series. In the present investigation the activity coefficients of naph-thalene in two series of salts are determined spectrophotometrically. The firstseries consists of seven sodium salts of fatty acids (sodium formate to sodiumn-heptylate), differing from one another only by the number of CH_2 groups inthe anions. The second series consists of ammonium bromide and three tetra-     

THE STATE OF CHROMIUM (Ⅲ) ION IN AQUEOUS SOLUTION

So far few systematic studies on the hydrolytic polymerization of Cr(Ⅲ) were reported because of inertness of the ion and complication of the process. We studied it in equilibrium by pH method systematically in a wide concentration range (0.0002—0.32 M). The results show that, in the low concentration range, the composition of the polynuclear hydrolysis products may be represented as [Cr_3(OH)_4] (OH)_n (n=1,2,3); in the medium range, the composition of products as Cr[Cr(OH)_2]_n~((3+n))~+ (n=1,2,3); in the high range, the composition of products as Cr[Gr(OH)]_n~((3+2n))~+ (n=1, 2), and in the intermediate range between medium and high range where the hydrolysis system is in a transition state, the composition of products as [Cr_3(OH)_3]~(6+) and [Cr_3(OH)_4]~(5+). The values of hydrolysis constants of the identical species measured in different Cr concentration ranges and calculated by different methods were found in good agreement with each other. A predominance-arca diagram was made by using the hy     

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.     

A SNIFTIRS STUDY OF THE BENZOQUINONE-BENZOHYDROQUINONE REDOX SYSTEM IN AQUEOUS SOLUTION

The in-situ FTIR spectroscopic results show that a hemi-ketal in-termediate may be produced in the electroreduction of benzoquinone or electro-oxidation of benzohydroquinone,which provides a valuable insight into the me-chanism of the redox process.