bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinetics of Heterogeneous Isotopic Exchange Reaction in Finite Bath
Authors: Huang Ting‐Chia , Tsai Fuan‐Nan 
Published: June 2015

AbstractA general method to find the rate constant and particle self‐diffusion coefficient is suggested for a heterogeneous isotopic exchange reaction which is controlled by surface mass reaction or controlled by a combination of surface mass reaction and intraparticle diffusion. The values of the kinetic parameter, ξ1 (ratio of the forward surface mass reaction rate to the intraparticle diffusion rate), particle self‐diffusion coefficient D and rate constant k are obtained by the proposed method for the isotopic exchange reaction systems CaCO3(s)/Ca2+(aq) and CaC2O4(s)/Ca2+(aq).
Molecular Structure of the Macrocyclic Ligand Complex (5, 7, 12, 14‐Tetraethyl‐7, 14‐Dimethyl‐1, 4, 8, 11‐Tetraazacyclotetra Decane) Nickel (II) Perchlorate
Authors: Lee T. J. , Lu T. H. , Liang B. F. , Chung C. S. , Lee T. Y. 
Published: June 2015

AbstractThe structure of macrocyclic ligand complex, (5, 7, 12, 14‐tetraethyl‐7, 14‐dimethyl‐1, 4, 8, 11‐tetraazacyclotetra decane)·NiII·(ClO4)2 has been determined by X‐ray diffraction with three dimensional counter data. This compound, C20H44N4NiII·(ClO4)2, crystallizes in orthorhombic space group Pbca, with cell parameters a=14.369, b=11.752, c=16.207 A, V=2736.8 A3, determined from Syntex Pl autodiffractomter. The formula weight (598.21) and a measured density of 1.45 gm cm−3 (by flotation) indicate the presence of four molecules per unit cell (Dc=1.452 gm cm−3). The structure was solved, using Patterson and Fourier methods and refined by full‐matrix least‐squares techniques to a reliability index, R(F) of 0.09, based on 1480 independent observed data corrected for absorption, L‐p factors. In this molecule, in addition to the usual covalent and ionic bonds, there exist two hydrogen bonds between the perchlorate ions and the amine groups. The Ni and the four N atoms are coplanar. The six membered ring subtends a larger angle (93.5(3)°) over the Ni atom than the five membered ring (86.5(3)°) does. The former belongs to the chair form and the latter pertains to the gauche form.
A Modified Kinetic Model for the Peroxydisulfate‐Iodide Reaction
Authors: Shih Yen‐Shiang , Cheng Ching‐Shang 
Published: June 2015

AbstractOne kinetic model for the oxidation of iodide ion by peroxydisulfate ion in aqueous solution is proposed. The reaction is regarded as \documentclass{article}\pagestyle{empty}\begin{document} {\rm S}_2 {\rm O}_8^{2 -} + {\rm I}^ - {\rm IS}_2 {\rm O}_8^{3 -} \end{document}, followed by the reaction \documentclass{article}\pagestyle{empty}\begin{document} {\rm IS}_2 {\rm O}_8^{3 -} + {\rm I}l_2 + 2{\rm SO}_4^{2 -} \end{document}. If the initial rates V are obtained from the formation of the iodine molecules, the reaction rate constant k1 and the ratio k2/k‐1 can be estimated by plotting the values of [S2O82−][I−]/V against that of 1/[I−]. The extrapolated value for k1 is 2.20×10−2 L/mol‐sec and k2/k‐1 is calculated to be 4.25×102 mol/L at 27°C in a solution with an ionic strength of 0.420.
Generalized Variation Theory—A New, Direct, Numerical Method for the Solution of General Eigenvalue‐Eigenvector Equation
Authors: Lin Chi‐Hsiung , Huang Win‐Hua , Su Chao‐Chang 
Published: June 2015

AbstractA new variation theory based on the behavior of function vector in a dual vector space is presented. The procedure is applicable to any quantum mechanical eigenvalue‐eigenvector problem and gives appropriate solution even with crude numerical integration to save computational cost. The theory offers an absolute measure of propriety for the assigned trial function. Applications on a free particle with a definite momentum, a particle in a one‐dimensional box with a definite energy, the one‐dimensional harmonic oscillator, and the ground state of helium atom are shown to demonstrate the merits of the theory.
Synthesis of 2‐(4‐Quinolyl) and 2‐(3‐Quinolyl) Chromone Derivatives
Authors: Hsu Kuang‐Kann , Sun Shao‐Wen , Chen Yueh‐Hung 
Published: June 2015

AbstractIn continuing search of the structure‐activity relationship of heterocyclic chromones, 4‐quinolyl and 3‐quinolyl moieties were each introduced to the C‐2 position of chromones. A total of 12 quinolyl chromones were synthesized. 4‐Quinolinecarboxaldehyde was condensed with 2‐hydroxyacetophenones to provide the chalcones. These intermediates were then subjected to selenium dioxide dehydrogenation to yield the 6 new 4‐quinolyl chromones. 3‐Quinolinecarboxaldehyde was condensed with 2‐hydroxyacetophenones in the presence of dilute alkali to give aldol compounds of chalcones (dehydration products of aldols). Ring cyclization of the chalcones yielded the other 6 new 3‐quinolyl chromones.
A Sensitive Spectrophotometric Determination of Tantalum (V) with 5,7‐Diiodo‐8‐Hydroxyquinoline
Authors: Sharma Yogendu 
Published: June 2015

AbstractA spectrophotometric method for the determination of trace amounts of tantalum (V) with 5–7‐diiodo‐8‐hydroxyquinoline is described. With this reagent tantalum forms a yellowish‐orange coloured complex which is stable in the pH range of 8.5–9.0. The coloured complex obeys Beer's law over the concentration range of 1–10 μg tantalum (V) ml−1 at 415 nm in aqueous solution with a molar absorptivity of 5.305×103 l mol−1 cm−1. The metal; ligand ratio ML2 was confirmed by Job's continuous variation and mole ratio methods. The method was used to determine tantalum in steels.
Spectrophotometric Estimation of Citral in Essential Oil
Authors: Nagar Meena , Baslas R.K. 
Published: June 2015

AbstractCitral forms an important constituent of many essential oils. It is present in a large number of essential oils containing lemon perfume and is of great commercial value. Methods of estimation of citral, available in literature are not very accurate or time consuming. The method developed by the author is based on colour change reaction of citral with rhodium (III). If all necessary requirements for experiment are ready, the estimation of citral occures within ten minutes. Rhodium (III) can also be determined with its colour change reaction by citral.
Solvent Extraction of Vanadium(V) as a Ternary Complex with N‐Hydroxy‐N‐p‐Chlorophenyl‐N′‐(2‐Methyl‐5‐Chloro)‐Phenyl‐p‐Toluamidine Hydrochloride and p‐Chlorophenol
Authors: Patel K.S. , Deb K.K. , Mishra R.K. 
Published: June 2015

AbstractN‐Hydroxy‐N‐p‐chlorophenyl‐N′‐(2‐methyl‐5‐chloro)‐phenyl‐p‐toluamidine hydrochloride (HCPMCPTH) reacts with vanadium(V) to form a 1:2 (metal:reagent) blue‐violet complex which can be quantitatively extracted into chloroform from acetic acid solutions. The deep blue adduct having 1:2:1 (V:HCPMCPTH:PCP) stoichiometry gets quantitatively extracted into chloroform from 0–2.5 M acetic acid media. The formation of the ternary complex has been made the basis for the development of a simple, rapid, sensitive and selective extractive‐photometric method for the determination of microamounts of vanadium(V). The method has been applied to the determination of vanadium in steels.
Copper(II), Nickel(II) and Cobalt(II) Complexes of Dibasic Tridentate Schiff Bases
Authors: Agrawal A.K. , Agrawal Sanjeev , Singh Nepal , Kansal B.D. 
Published: June 2015

AbstractComplexes of Cu(II), Ni(II) and Co(II) with the Schiff bases derived from o‐aminobenzoic acid with salicylaldehyde and its 5‐chloro and 5‐bromo derivatives have been prepared. The 1:1 (metal‐ligand) stoichiometry of these complexes is shown by elemental analysis, gravimetric estimations and conductometric titrations while the structures of the complexes are proved by i.r. spectra and thermogravimetric analysis. The magnetic susceptibility and electronic spectra of Cu(II) complexes indicate the nonplanar binuclear structures while that of Ni(II) and Co(II) show their paramagnetic octahedral geometry. The molar conductance values in nitrobenzene indicate the nonelectrolytic behaviour of the complexes. The results show that the complexes of the type (Cu·L)2, Ni·L·3H2O and Co·L·3H2O are formed having solvent molecule in coordination with the metal ion. The monopyridine and monoammonia adducts of Cu(II) complexes were found to be monomeric.
Mössbauer Studies on Spin State of the Thermal Decomposition of Substituted Tris (2‐Pyridylimine) Iron (II) Thiocyanate
Authors: Wei Ho‐Hsiang , Hsiao Ching‐Sung 
Published: June 2015

AbstractThe spin states of iron (II) in FeL2(NCS)2 produced from the thermal decomposition of FeL8(NCS)2 (L=2‐py‐CR1=NR2, R1 or R2=H, Me(CH3), Ph) under nitrogen atmosphere are investigated by means of Mössbauer spectroscopy and magnetic measurements. It was found that the spin states of iron (II) in substitutited bis (2‐pyridylimine) iron (II) thiocyanate are included: intermediate‐spin (3T1, S=1), mixed‐spin of 5T2(S=2)+3T1 and spin incomplete transition of 5T2⇌3T1.
Polarography of Molybdenum (VI)—Gallic Acid Complexes in Perchlorate Media
Authors: El Inany G. , Zidan F. , El Shetary B. 
Published: June 2015

AbstractPolarographic and spectrophotometric studies were carried out on Mo (VI)—gallic acid (G) complexes in aqueous solution of perchlorate media. It was found that the number of waves of Mo (VI) depends on gallic acid concentration as well as on the pH of solution. Only a single well‐defined irreversible wave is obtained at pH 8.0 for the reduction of Mo (VI) to Mo (III), proportional to Mo (VI) concentration in presence of 20 mM gallic acid with E1/2=−1.22 V vs SCE. The composition of the formed complexes depends on the pH of solution as revealed from spectrophotometric studies, a 1:1 Mo/G complex is formed at pH 3.0 and 1:2 complex at higher pH′s‐NMR study of the isolated 1:2 complex proves that the complexation occurs through—OH groups of gallic acid.
Effect of Solvents on the Spectra of Some N′‐2‐(Substituted Pyridyl)‐N‐Substituted‐Thioureas
Authors: Khurana O. P. , Tyagi J. S. , Taneja A. D. 
Published: June 2015

AbstractSome N′‐2‐(substituted pyridyl)‐N‐substituted thiourea (in all 12‐substituted pyridyl thioureas) have been examined in ultraviolet region in a series of solvents covering a broad polarity range i. e. from benzene (Z, 54.0) to ethylene glycol (Z, 85.1). Transition energies and oscillator strengths have been calculated and transition energy (ET) has been plotted against Z‐values, a new‐empirical measurement of solvent polarity. A linear relationship was observed between the transition energy and Z‐value for pyridyl μ→μ* and thiocarbonyl μ→μ* transitions. The effect of substituent present in pyridyl group on λmax of a compound in the same solvent has been studied. Solvent sensitivites of these ligands have also been calculated.
Mechanistic Studies on Rhodium(III) Chelates Aquation of Cis‐Dinitrobisbiguaniderhodium(III) Nitrate
Authors: Chakravarty B. , Nandi B. 
Published: June 2015

AbstractAquation of cis‐dinitrobisbiguaniderhodium (III) nitrate was investigated conductometrically. Rates of the release of first and the second nitro groups were derived by a graphical method. For both the steps of aquation, the presence of electron accepting ‘nitro’ group, favours ‘bond formation’ by the incoming ligand in the transition stage and it occurs before the ‘bond rupture’ is complete. The loss of the second ‘nitro’ group most probably takes place along with a hydrogen ion from the ‘aquo’ ligand introduced in the first step of aquation with the resultant formation of the hydroxoaquobisbiguanide complex. Activation parameters were evaluated and are as follows: ΔH‡ are 18±1.2 and 18.6±1.1 k cals mole−1 and ΔS‡ are −15±2.7 and −19±2.3 e. u. respectively for the first and the second steps of aquation.
Kinetics and Mechanism of Oxidation of Adipic Acid by Ce(IV) Ion in Acidic Medium
Authors: Kansal B. D. , Pal Virendra , Singh N. , Maheshwari V. K. 
Published: June 2015

AbstractKinetic study of oxidation of adipic acid by Ce(IV) ion in aqueous solution of sulphuric acid shows that the reaction follows first order kinetics in both Ce(IV) and adipic acid and the over all reaction order ascertained is two. The specific rate constant increases with an increase in the concentration of adipic acid. Effects of hydrogen ion concentration, bisulphate ion and temperature have been studied in detail. Various kinetic parameters have been computed. The experimental findings are consistent with the mechanism involving rapid resersible formation of an activated complex between Ce(IV) and adipic acid followed by a rate determining step involving C‐C bond fission.
CNDO Calculation and Homo Repulsive Bond Order of Aromatics
Authors: Chen Cheng 
Published: June 2015

AbstractThe author et al. has recently developed a s‐p separation model CNDO‐MO method. Naphthalene, anthracene and their derivatives including CI and CH3 substituted functional groups have been selected for the MO calculation. The computational results of both the ionization potentials and the dipole moments are compatible with current experimental values. We here introduce a concept of the HOMO repulsive bond order (Pp(HOMO)µv). Then it is calculated in addition to repulsive bond order (Ppµv) developed previously in this work. The result shows that both HOMO eigenvalues and the Pp(HOMO)µv are the useful and powerful quantities for the predictions of reactivity and positional selectivity of the Diets Alder reaction.
Polymer‐Attached Thiazolium Salts‐Catalyzed Addition of Aldehydes to α, β‐Unsaturated Carbonyl Compounds
Authors: Chang Biau‐Hung , Chang Yueyeh L. 
Published: June 2015

AbstractA homogeneous catalyst, 3‐benzyl‐5‐(2‐hydroxyethyl)‐4‐methyl‐1,3‐thiazolium chloride, for addition of aldehydes to activated double bond, was attached to 20% cross‐linked polystyrene‐divinylbenzene copolymer. The attached catalysts could be easily removed from the reaction mixture. Polymer‐attached thiazolium salts in the presence of triethylamine are active catalysts for addition of aromatic and aliphatic aldehydes to α,β‐unsaturated ketones to yield γ‐diketones.
Spectrophotometric Studies of Cerium(III) and Thorium(IV) Chelates of Diethylenetriaminepentaacetic Acid (DTPA)
Authors: Hseu Tong‐Ming , Peng Ling , Lin Zui‐Feng 
Published: June 2015

AbstractThe interaction between diethylenetriaminepentaacetic acid (DTPA or HsZ) and Ce(III) and Th(IV) ions has been investigated spectrophotometrically in aqueous solution at an ionic strength of 0.1 and for various temperatures. It has been found that the Ce(III)‐DTPA chelate (1:1) exhibited a characteristic absorption maximum at 297 nm, and the optimum pH range is between 3.4 to 4.4. The absorption of Ce(III)‐DTPA chelate is considerably diminished by adding small amounts of Th(IV) ions. This phenomenon was used to evaluate the formation constant of Th(IV)‐DTPA chelate (1:1). The formation constants and the thermodynamic properties characterizing the formation of the chelates have been calculated at 25°. The results are as follows:
On the Autocatalysis of Methane Pyrolysis
Authors: Tu Y.‐T. , Yeh Chuin‐Tih 
Published: June 2015

AbstractMethane pyrolysis has been performed in a recycled flow system in the temperature range of 1103 to 1220 K to investigate the time profile of product distribution. Hydrogen, ethylene, and benzene are found to be the major products before the soot formation. Similar to the literature reports of studies in conventional flow systems, the rate of methane conversion is slow at the beginning of the decomposition and becomes fast after an incubation period. This increase in the decomposition rate after the incubation period is generally called autocatalysis. The proposed reason for this autocatalysis has been the catalytic effect of the secondary products, i.e., soots and carbon deposits. The present study showed that autocatalysis started before the accumulation of these products, and that decomposition of propylene and other minor but reactive products might be attributed to this autocatalysis effect.
Constituents of Ilex Species I. On the Leaves of Ilex Cornuta Lindl
Authors: Gau Shwu‐Wen , Chen Chien‐Chih , Chen Yuh‐Pan , Hsu Hong‐Yen 
Published: June 2015

AbstractPhytochemical examination on the leaves of Ilex cornuta Lindl. (Aquifoliaceae) resulted in the isolation and identification of lupeol (I), 3β‐hydroxylup‐20(29)‐en‐30‐al (II), oleanolic acid (III), and β‐sitosterol‐β‐D‐glucoside (IV).
Constituents of Formosan Rhamnus Species Part II. Flavonoids from Rhamnus Formosan Matsum
Authors: Chung Mei‐Ing 
Published: June 2015

AbstractThree crystalline compounds, rhamnetin(1), rhamnocitrin(4), and kaempferol(6) were isolated from the hot methanol extract of leaves of Rhamnus formosana Matsum.
Complexes of Oxamic Acid with La(III), Gd(III), Tb(III), Er(III), Tm(III) and Lu(III)
Authors: Zafiropoulos Th. F. , Perlepes S. P. , Galinos A. G. 
Published: June 2015

AbstractThe preparation, for the first time, of the deprotonated complexes of oxamic acid with La(III), Gd(III), Tb(III), Er(III), Tm(III) and Lu(III) is reported. Analytical results, conductometric measurements, magnetic moments and spectral data (IR and diffuse reflectance spectra) are discussed in terms of possible structural types. The oxamate anion acts as a N, O bidentate non‐bridging ligand.
Studies of C. I. Acid Red 186 and Metal Complexes with Uo++2, Ce3+ and Th6+ Ions
Authors: Abd‐El‐Kader A. K. , Abu‐El‐Wafa S. M. , Ezz‐El‐Arab M. A. 
Published: June 2015

AbstractThe electronic absorption spectra of C. I. Acid Red 186 are studied in solution of different pH. The pK values of the acid‐base equilibria set are determined and commented upon. The complexes of UO++2, Ce3+ and Th4+ ions are investigated by some spectroscopic techniques and potentiometric titration. The formation of 1:1, 1:2 and 1:2 complexes (M:L) with UO2++, Ce3+ and Th4+ respectively is confirmed and their conditional stability constants are determined. The solid complexes are prepared and analysed for their metal content, their ir spectra are disussed in comparison to that of the ligand to establish the bonding between the ligand and metal ions.
Preparation of Iron Carbonyls Supported on Organic Polymers
Authors: Chou Ta‐Shue , Feng Jung‐Jung 
Published: June 2015

AbstractTriphenylphosphine ligand functionality could be readily introduced onto the 2% DVB and 12% DVB cross‐linked polystyrenes. Significant differences in reaction rates and loading capacities were observed in favor of the 2% DVB percentage cross‐linkage. The reaction of iron pentacarbonyl with polymeric ligand gave both monocoordination and biscoordination products. Product distribution analyses indicated that monocoordination was favored for both kind of polymeric ligands. Ratio of biscoordination to monocoordination was higher for the 2% DVB polystyrene ligand than for the 12% DVB polystyrene ligand indicating biscoordination proceeded more easily on the former.
Mössbauer Line Shape of Frozen Aqueous Solutions
Authors: Cheng H. S. , Hsu C. M. 
Published: June 2015

AbstractIsomer shift of simple lines of the frozen mixture solutions of SnCl5H2O and K2SnF6 were linearly related to mole fraction and, therefore, to average ligand number, ñ. These spectra corresponded to Sn(H2O)6‐ñFñ(‐ ñ)+. Assuming that quadrupole splitting was also linearly related to ñ, Mössbauer spectra of Sn(ClO4)2 solutions containing different amount of HF could be resolved into components.
Mössbauer Spectroscopic Determination of Stability Constants of Fluorostannate(II) Complexes
Authors: Cheng H. S. , Hsu C. M. , Wei H. H. 
Published: June 2015

AbstractStability constants of fluorostannate(II) complexes were determined Mössbauer spectroscopically by rapid freezing technique. The observed isomer shift values suggested that these complexes were hydrogen bonded in perchloric acid solutions.
Mössbauer Spectroscopic Studies of Chlorostannate(II) Complexes in Frozen Aqueous Solutions
Authors: Cheng H. S. , Hsu C. M. , Shih L. L. 
Published: June 2015

AbstractMössbauer parameters of frozen aqueous solutions of Sn(ClO4)2 in 0.5 M HClO4 did not change with the concentration of NaClO4, so that it was used to keep the ionic strength at the desired level. When NaCl was added into Sn(ClO4)2 solutions, isomer shift did not change, but quadrupole splitting did. Therefore, stability constants were calculated from the quadrupole splitting data, which were in good agreement with the published values. The observed spectra could be resolved into components.
The Polarographic Behaviour of Some Arylidene Benzoic Hydrazide Derivatives and Substituent Effect
Authors: Hindawey A. M. , El‐Baradie H. Y. F. , Mohamed G. B. 
Published: June 2015

AbstractThe polarographic reduction of some arylidene derivatives of benzoic hydrazide are investigated at the DME. The polarograms in solutions of pH≤8 consist of a single wave corresponding to 4 electrons in acid media and 2 electrons in alkaline ones. The wave splite into two daughter waves in media of pH≥10, the more negative wave increases in height at the expense of ihe original one with rise of pH. The reduction waves are essentially diffusion controlled with one proton and two electrons in the rate determining step. The electrode reaction is discussed and the important kinetic parameters are determined.
Chemistry of o‐Benzoquinones and Masked o‐Benzoquinones. VI. Cycloaddition of 6, 9 Dipropyl‐1, 4‐Dioxaspiro[4.5] Deca‐6, 8‐Dien‐2, 10‐Dione with Cycloheptatriene
Authors: Hsu Y. H. , Kuo L. C. , Liao C. C. 
Published: June 2015

AbstractCycloaddition of masked o‐benzoquinone, 6,9‐dipropyl‐1, 4‐dioxaspiro[4.5]deca‐6, 8‐dien‐2,10‐dione, with cycloheptatriene afforded mainly [4π+2π] adducts which was transformed into 1, 4‐dipropyl‐5H‐benzocycloheptene by hydrolysis, photolysis and dehydrogenation consecutively. These reaction sequences represent a novel method for the synthesis of 5H‐benzocycloheptene from catechol via masked o‐benzoquinone.
Concentration Dependence of Mössbauer Parameters of SnCl−3 and SnBr−3 Complex Ions
Authors: Hsu C. M. , Cheng H. S. 
Published: June 2015

AbstractMössbauer parameters of frozen salt solutions could be correlated with apparent degree of dissociation, γ. KSnCl3 and KSnBr3 were dissolved in 0.5 M H2SO4, whereas NH4 SnCl3 was dissolved in 0.5 M HClO4. Mössbauer studies were made at different concentrations.
Mössbauer Spectroscopic Studies of K2SnCl6 and SnCl4·5H2O in Frozen Aqueous Solutions and in Ion Exchange Resins
Authors: Cheng H. S. , Hsu C. M. , Uen T. M. , Tseng P. K. 
Published: June 2015

AbstractConcentration dependence of isomer shift of K2SnCl6 and tin(IV) chloride was studied. Tin was hydrolyzed in both cation and anion exchange resins after water washing. Two pairs of these two solutions showing the same isomer shift values, and therefore the same , were selected for further studies in HCl solutions and in anion exchange resins. The first pair was 0.04 M K2SnCl6 and tin(IV) chloride solutions (δ=0.00 mm/s; =0): Their δ‐[HCl] curves coincided each other. Tin was sorbed on anion exchange resin as pentachlorstannate(IV) at (HCl)≤6 N, and chiefly as hexachlorostannate(IV) at [HCl]≥7 N. The both complexes were sorbed when 6 N < [HCl] < 9 N. The δ‐[HCl] curves of the second pair, 0.4 M K2SnCl6 and 3 M tin(IV) chloride(δ =0.23 mm/s; =3), also coincided each other, and tin was sorbed as pentachlorostannate(IV) from K2SnCl6 solutions in the HCl concentration range studied (≥5 N).
Spectrophotometry Determination of Iron(II) Separated by Means of Adsorption of Its 3‐(2‐Pyridyl)‐5, 6‐Diphenyl‐1, 2, 4‐Triazine Complex with Tetraphenyl‐Borate on Microcrystalline Naphthalene
Authors: Lin Jenn‐Lin , Chang Lih‐Fen 
Published: June 2015

AbstractA procedure is describe for the adsorption of ion‐associated complex of iron(II) 3‐(2‐pyridyl)‐5, 6‐diphenyl‐1, 2, 4‐triazine (abbreviated as PDT) cation with tetra phenylborate (TPB) anion on macrocrystalline naphthalene. A water‐insoluble ion‐associated complex formed with PDT and TPB is quantitatively adsorbed on micro‐crystalline naphthalene. The solid mixture containing the colored complex is dissolved in acetonitrile and the absorbance was measured at 553 nm. The other factors such as pH, amounts of reagents and naphthalene, shaking and standing times, diverse ions are studied. The method has been applied for the determination of iron in alloys and water samples.