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1.
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%.  相似文献   

2.
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.  相似文献   

3.
1. INTRODUCTION Resin phase spectrophotometry belongs to solid spectrophotometry. It is a new kind of luminosity analysis technology, which comes from the combination of solid extraction technology and luminosity analysis technology. This method is especially suitable for analyzing low component environment water sample, high purity substance and complicated sample component because it incorporates sensitivity (associated by ion exchange), concentration, separation and determination. So m…  相似文献   

4.
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.  相似文献   

5.
1.INTRODUCTIONThinlayerresinphasespectrophotometryisanewanalyticalmethodinthefieldofspectrophotometricanalysis;ittakesitssourceattheliquid-liquidextractiontechniquesincombinedwithclassicalspectrophotometricanalysis.Thesubstanceofproposedmethodisaccordingtounderprinciplesthatthetargetmetalionswasassociatedwithsomeligandsinaqueousphase,thentoformedaternaryormulticomponentcomplexions,suchasanioncomplexes.Aftertheassociationreactionwasfinished,thecomplexionswillassociatedwithaion-exchangeresin…  相似文献   

6.
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.  相似文献   

7.
The compositional heterogeneity has been studied for a series of PCL/MDI/BDO segmentedpolyurethanes. Their average hard segment content measured by NMR method was ranging from17% to 42%. Macromolecules of segmented polyurethanes can be separated according to theircomposition by TLC technique with a mixed solvent of toluene/acetone/ tetrahydrofuran as the devel-oper. A dual wavelength TLC spectrodensitometer was used for quantitative analysis of TLC results,and method for data treatment is proposed to obtain the composition distribution with no need ofany reference samples as TLC elution standards. The polyurethane samples are found to be hetero-geneous in composition, having bimodal distribution curves.  相似文献   

8.
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.  相似文献   

9.
1INTRODUCTIONWriboseisimPObotfortheactivitiesoflivingorganismsandcanbewidelyusedinpharmaceutical,foodandforageindustriesll.ZI.Itcanbeproducedbyfermentationofglucosewiththesubnutritionalmutantstrainoftheilliciumoill3.41.ruribosedemoticfluidhasacidicproperty,itScolorisdarkreddish.Itcontainsphosphateion,chlorideionandalittlequantityofsulfateionandoxalateion.Potassiumionandalittlequantityofsodion,calciumionandmagnesiumioncanalsobefound.Becauseofplentyofimpuritiesinthefluidandthedarkcoloroft…  相似文献   

10.
A quite new type of chelating resin CarboxymethylatedPolyethylenimine-Polymethylenepolyphenylene Isocyanate(CPPI)is usedfor the preconcentration of Zn from high salt water such as seawater.The preconcentration is controlled through the technique of FlowInjection Analysis(FIA).The concentrated sample solution is thendirectly transferred to an Inductively Coupled Plasma-AtomicFluorescence Spectrometer(ICP-AFS)for determination.The detectionlimit of Zn by the technique is about 0.06 ppb.  相似文献   

11.
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 asRp = Ke-56400/RT[MMA]1.57[CCl4]m[RESIN-Cu]0.18where 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.  相似文献   

12.
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.  相似文献   

13.
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…  相似文献   

14.
STUDYONCONTINUOUSELECTROREGENERATIONOFIONEXCHANGERESINXuTaishun(ShanghaiinstituteofElectricPower,Shanghai200090,China)Abstrac...  相似文献   

15.
In Britton-Robinson buffer,metronidazole is preconcentreted on HHDE at 0.0 V(Vs.Ag-AgCI),An adsorptive stripping peak is observed at-0.62 V.Tho response is linear from 1x10~(-8)to1×10~(-6)mol/L with 1.5 min accumulation.The method has been successfully applied to the deterination of metronidazole in human serum and formulations.  相似文献   

16.
Werborne ultrafine particles of epoxy resin were prepared by phase inversion tech-nique. The results of SEM revealed that the particles diameter was in the range of 50to 100 nm and the effects on amount of water required at phase inversion point were alsodisc?d.  相似文献   

17.
With derivative spectrophotometric method,the complexes oflanthanides with 2-(5-bromo-2-pyridylazo)-5-diethylaminophen-ol(5-Br-PADAP)in the presence of octylphenol poly(ethyleneg-lycol)ether(TX-100)were studied.It is found that the maximumabsorption of fourth-order derivative spectra of the neodymiumcomplex by 4f electron transitions is at 579(+)nm and 582(-)nmwith molar derivative absorptivities of 5.2×10~3 1.mol~(-1).cm~(-1).The maximum absorption of the zero-order derivative spectra ofthe complexes for neodymium and praseodymium is at 580hm,themolar absorptivities are 1.47×10~5 l.mol~(-1).cm~(-1)for Nd and 1.26×10~5 l.mol~(-1).cm~(-1)for Pr.The component ratio of the complexis Nd:5-Br-PADAP=1:4.Beer's law is obeyed in the range of0-3.75μg of Nd and Pr in 25ml of solution.The method has beenused for the simultaneous determination of Nd and Pr in foursynthetic samples and the results obtained are satisfactory.  相似文献   

18.
The behavior of chloride adsorbed on Ag(100) electrode has been studied using chronoamperometric technique, and the structural transition of chloride layer has been confirmed.  相似文献   

19.
Toughened epoxy resin with excellent properties was obtained by adding organic acid anhydride curing agent and hydroxy-terminated butadiene-acrylonitrile copolymer (HTBN), which is cheaper than CTBN. The anhydride reacts with both epoxy groups on epoxy resin and hydroxyl groups on HTBN. As a result the soft long chains of HTBN and the rigid chain of epoxy resin form one network, giving the resin toughness. Two-phase structure of the toughened resin was observed by SEM and TEM.  相似文献   

20.
Oilless alkyd resin modified with the silicoorganic compounds has been obtainedsuccessfully by polymerization.At appropriate proportion of silicoorganic compounds,thepolymerized product has higher hardness and lustre than that of oilless alkyd resin.  相似文献   

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