A STUDY ON THE KINETICS OF EXCHANGE REACTIONS OF W（VI） OR Mo（VI） WITHIN人MACROPOROUS ANION EXCHANGE RESIN（D290） PHASE

The exchange behaviors of WO4^2-,MoO4^2-,H2W12O46^6- and Mo8O26^4- anions within macroporous exchange resin(D290) phases have been studied.The values of diffusion constant(B),inner diffusion coefficient(D^-),retarted time(τd) half-exchange-period(t1/2), and activation energy(ΔE） were found from the kinetic analyses.A new method to separate W(VI) and Mo(VI) from each other was also suggested.     

THE EFFECT OF IONIC STRENGTH ON THE UPTAKE OF TAURINE ON A STRONG-BASIC ANION EXCHANGE RESIN

1. INTRODUCTION Taurine (NH2CH2CH2SO3H) is one of the most important amino acids in the human body, and plays an important role in a variety of physiological functions, pharmacological actions and pathological conditions, such as in controlling epilepsy, hypertension and arrhythmia. It is also often used to recover osmotic pressure and promote cerebrum growth [1,2]. As one of amino acids, taurine had the amphoteric characteristic which can be utilized in the ion-exchange technique to e…     

STUDY ON THE ION EXCHANGE KINETICS—A NEW ION EXCHANGE KINETICS EQUATION

A new ion exchange kinetics equation including resin phase saturation factor is presented in this paper. The equation is characterized by the apparent reaction order and apparent saturation order.     

THE STUDY ON TRE KINETICS AND MECHANISM OF THE REACTIONS OF METAL IONS WITH PnAO

The kinetics and the mechanism of the formation reactions ofM(PnAO)~(2+)(M=Ni,Co,Cu)were studied with UV Spectrophotometer and StoppedFlow Spectrophotometer and a three steps mechanism was suggested.     

A STUDY ON THE CRYSTALLIZATION KINETICS OF NYLON 1010

The kinetic behavior of isohermal and nonisothermal crystallization of nylon-1010has been studied by means of dilatometry and differential scanning calorimetry, respec-tively. The isothermal and nonisothermal process can be descibed by Avrami equationand Ozawa equation, respectively. From the experimental results the kinetic paramters ofcrystallization and crystalline mechanism for isothermal and nonisothermal measurementsare discussed.     

STUDY ON THE PHASE TRANSITION KINETICS OF THERMOTROPIC LIQUID CRYSTALLINE AROMATIC-ALIPHATIC COPOLYESTER

The phase transition kinetics of thennotropic liquid crystalline aromatic-aliphatic regular copolyester: were studied by DSC. By means of Kissinger's method the kinetic equation and parameters including activation energy, rate order and preexponential factor for phase transition from nematic to isotropic were obtained. The activation energy from crystal to nematic was also presented.     

STUDY ON THE DETERMINATION OF TRACE Fe（III） BY THIN LAYER RESIN PHASE SPECTROPHOTOMETRY

A method to determine Fe（Ⅲ） by thin layer resin phase spectrophotometry has been developed in this paper. The colored complex formed by Fe（Ⅲ） and 1,2-benzendiol is concentrated on the 717^# resin, then Fe（Ⅲ） can be determined directly by making thin layer. The method is sensitive with a apparent molar absorption of 4.8×10^4L/mol.cm, which is 16 times higher than that of liquid phase spectrophotornetry, most coexisting ions do not influence the determination. The detection limit for Fe（Ⅲ） is 1.47μg/L with the precision of 3.3% [n=6, 7μg/50mL Fe（Ⅲ）]. The calibration curve is linear in the range of 0-25μg/50mL. The preposed method was applied to the determination of Fe（Ⅲ） in water sample with satisfactory results.     

A STUDY ON THE TOUGHENING OF EPOXY RESIN BY HTBN-EPOXY RESIN PRECOPOLYMER

A novet toughened epoxy resin was obtained by using aprecopotymer of epoxy resin and hydroxy-terminated butadiene-acrylonitrilecopolymer(HTBN)and amine curing agent.The cured toughened resin hasexcellent mechanical properties due to the two-phase structure,which has beenobserved from SEM and TEM.     

STUDY ON THE POST-CURE KINETICS OF EPOXY RESIN IRRADIATED BY AN ELECTRON BEAM

INTRODUCTIONElectron Beam (EB) curing of polymer matrix composites is a novel green manufacturing process. EB curing ofcomposites offers significant advantages over traditional thermal curing[1-3], including shorter curing time, lowenergy consumption, low curing temperature, good dimensional stability, better processing character, and so on.According to the curing reaction mechanism of epoxy resin initiated by onium salt, the curing reactionincludes three reaction steps of chain initiati…     

STUDY ON THE DETERMINATION OF TRACE BISMUTH（III） BY THIN-LAYER RESIN PHASE S PECTROPHOTOME TRY

In this paper, a new thin-layer ion-exchange resin phase analytical method is introduced. It is based on that, the bismuthous cation can associate with iodic anions, so as to formed an anion complex [BiI4-_] in a strong acidic environments. This anion complex can also exchanges with a weaker anions on the surface active site of anion exchange resin, so that a[R+] [Bil4-] solid phase binary associational system is produced. Owing to the solid system is a great many dispersive particulates, it can be pressed to a thin-layer by press tools of the so called “thin-layer resin phase “ or “resin phase “, and using this solid association system spectrophotometry for the determination of trace metals. So it can increase the analytical sensitivity. This association system exhibits maximum absorbance at 460nm, and obeys Beer‘s law over the concentration range 0.0lug/ml-l.20ug/ml of bismuthous(lll), h has a molar absorptivity of 7.1×l^5 [L/mol.cm]. it indicated the resin phase spectrophotometry is a sensitive analytical method for trace bismuthous. It is 18 times higher than routine aqueous spectrophotometry. The relative standard deviations is 1.82% (n=6) for the F fmeasurements of 0.Sug/ml Bi(llO. The detection limit of Bismuthous(lll) is 1.4 XlO~mol/L. The method has applied to the analysis Bi(lll) in environmental water samples.     

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.     

STUDY ON THE KINETICS OF POLYMERIZATION OF MMA BY COPPER（Ⅱ） CHELATING RESINS

The polymerization of MMA initiated by copper(Ⅱ） chelating resins/CCl4 system was studied.From the kinetic data,the kinetic equation of polymerization can be expressed as Rp=Ke^-56400/RT[MMA]^1.57[CCl4]^m[RESIN-Cu]^0.18 where m:3-4.5,when[CCl4] 0.1-6.93M.The free radical polymerization mechanism is proposed.The primary radicals are formed by the process of complexation-chlorine transformation among the copper(Ⅱ) chelating resin,CCl4 and methacrylate.     

A COMPARATIVE STUDY ON THE PHOTOVOLTAIC PROPERTIES OF BUCKMINSTERFULLERENE （C60） AND ITS ANION SALT

ＡＣＯＭＰＡＲＡＴＩＶＥＳＴＵＤＹＯＮＴＨＥＰＨＯＴＯＶＯＬＴＡＩＣＰＲＯＰＥＲＴＩＥＳＯＦＢＵＣＫＭＩＮＳＴＥＲＦＵＬＬＥＲＥＮＥ（Ｃ６０）ＡＮＤＩＴＳＡＮＩＯＮＳＡＬＴ￥ＺｈａｎＪｕｎＹＵ；ＰｅｎｇＺＨＡＮＧ；ＬｉｎＳｏｎｇＬＩ；ＤｅＪｕｎＷＡＮ...     

STUDY ON THE DETERMINATION OF TRACE BISMUTH(III) BY THIN-LAYER RESIN PHASE SPECTROPHOTOMETRY

1.INTRODUCTIONThinlayerresinphasespectrophotometryisanewanalyticalmethodinthefieldofspectrophotometricanalysis;ittakesitssourceattheliquid-liquidextractiontechniquesincombinedwithclassicalspectrophotometricanalysis.Thesubstanceofproposedmethodisaccordingtounderprinciplesthatthetargetmetalionswasassociatedwithsomeligandsinaqueousphase,thentoformedaternaryormulticomponentcomplexions,suchasanioncomplexes.Aftertheassociationreactionwasfinished,thecomplexionswillassociatedwithaion-exchangeresin…     

STUDY ON THE DECOLORIZATION OF D—RIBOSE ZYMOTIC FLUID BY RESIN ADSORPTION

In this paper,effects on of six type of resins the decolorization of D-ribose zymotic fluid have been studied for the first time.The results show that resin NKA-II has the best effect.the decolorization rage of D-ribose zymotic fluid is 91% at velocity of 1.0BV/hr and 25℃,the adsorption capacity can reach up to 5.7BV.The effects of adsorption conditions as well as conditions of resinregeneration on the resin decolorization capability were also studied.     

STUDY ON DETERMINATION OF TRACE Cu（Ⅱ） BY DDCT CHELATING RESIN PRECONCENTRATION AND THIN LAYER RESIN PHASE SPECTROPHOTOMETRY

A new method for determination of Cu(Ⅱ) by DDCT chelating resin preconcentration and thin layer resin phase spectrophotometry was developed. The method has a high sensitivity (ε435 =3.6×105 L/mol· cm), which is 33 times higher than that of liquid phase spectrophotometry. It has a good selectivity (most coexisting ions could not influence determination) and an ideal precision [30μg Cu(Ⅱ), n=6, RSD= 1.67%]. The content of Cu(Ⅱ) in water, high purity rare earth and its oxide was determined. The detection limit of Cu(Ⅱ) is 5.3μg/L, and the linear range is 0～7.2 μg/ml. The result is satisfactory.     

STUDY ON DETERMINATION OF TRACE Fe BY Fe（Ⅱ）-VA THIN LAYER RESIN PHASE SPECTROPHOTOMETRY

A new method for the determination of Fe by thin layer resin phase spectrophotometry in alkali condition was reported. The complex anion formed by Fe(Ⅱ) and VA was absorbed on the 717#resin and Fe was determined by making thin layer. This method had a high sensitivity (ε620=3.0×105 L/mol·cm), which was 15 times higher than that of liquid phase spectrophotometry. It had been proved a satisfactory precision (5.0μg Fe, n=6, RSD=1.8%). The trace Fe in natural water was determined and the recovery was 97%.     

W（Ⅵ）,Mo（Ⅵ）在D290树脂相内的吸附动力学（Ⅱ）

本文用浅床法按Boyd方程,研究了H_2W_(12)O_(40)~(6-)和Mo_8O_(26)~(4-)离子在D290大孔阴离子交换树脂相内的扩散动力学特性。分别测定了上述两种离子的半交换期t_(1/2)、扩散常数B、内扩散系数(?)、阻滞时间τ_d。同时将H_2W_(12)O_(40)~(6-)与WO_4~(2-),Mo_8O_(26)~(4-)与MoO_4~(2-)离子的诸动力学参数作了比较。     

D290大孔阴离子交换树脂对W（Ⅵ）、Mo（Ⅵ）吸附性能的研究

本文研究了D290大孔阴离子交换树脂吸附W（Ⅵ）、Mo（Ⅵ）时，酸度、浓度、温度、流速等对吸附量的影响。确证了该种树脂对W（Ⅵ）、Mo（Ⅵ）的偏酸根吸附量大于其正酸根的吸附量，但交换速度慢于后者的交换速度。并研究了在上述诸条件下，D290树脂从溶液中分离钨、钼的方法。     

A STUDY ON ELECTRONIC STRUCTURE OF BIS（2，4—DIMETHYLPENTADIENYL） TETRAMETHYLENEDIAMINE POTASSIUM COMPLEX ANION

<正> Electronic structure of the title compound is studied based on the CNDO/ 2 calculations. The bonding interactions in the complex are discussed on the basis of molecular orbital components, charge distribution and bond orders. The calculated results and the discussion are beneficial to the understanding of the structure and properties of this sandwich-like comppund.