bluuebunny/crossref_metadata_2025 huggingface dataset:
Extraction Studies of Fe(II) Ion from Hydrochloric Acid Solutions by di‐(2‐Ethylhexyl) Phosphoric Acid
Authors: Yang Chao‐Yeuh , Shih Jeng‐Shang , Yeh Yu‐Chai
Published: June 2015

The partition of Fe(II) between hydrochloric acid solution and solvent of di‐(2‐ethylhexyl)‐phosphoric acid (HDEHP) in kerosene has been studied at varying concentrations of hydrochloric acid, solvent and Fe(II) ion. A stoichiometric extraction equation was derived as:

Fe2+(a)+2(HX)2(0)=FeH2X4(0)+2H+(a)

where the subscripts a and o refer, respectively, to aqueous and organic phases. Corresponding to the stoichiometries, value of Ks which equaled was obtained from the plot of D[H+]2 vs. F2 where D is the observed distribution ratio, F the concentration of HDEHP in organic phase. The kinetic studies of the extraction of Fe(II) species from hydrochloric acid into HDEHP under nitrogen atmosphere was carried out and the forward and back reaction constant was calculated. Also the oxidizing effect of air on the HDEHP‐Fe(II) complex in organic phase was studied.
Studies on the Constituents of Paris Formosana Hayata Part II
Authors: Yeh Pen‐Ho , Chiang Hsüch‐Ching
Published: June 2015

Methyl palmitate (I), methyl stearate (II), stigmasterol (III), β‐sitosterol (IV), (O‐acyl)‐β‐D‐glucopyranosyl‐(1→3)‐stigmasterol (V), (O‐acyl)‐β‐D‐glucopyranosyl‐(1→3)‐β‐sitosterol (VI), β‐D‐glucopyranosyl‐(1→3)‐stigmasterol (VII), β‐D‐glucopyranosyl‐(1→3)‐β‐sitosterol (VIII), β‐D‐ecdysone (IX), diosgenin‐3‐α‐L‐rhamopyranosyl‐(1→2)‐[α‐L‐arabinofuranosyl‐(1→4)]‐β‐D‐glucopyranoside (X), diosgenin‐3‐O‐β‐chacotrioside (dioscin) (XI), and diosgenin‐3‐O‐α‐L‐rhamnopyranosyl‐(1→4)‐α‐L‐rhamnopyranosyl‐(1→4)‐[α‐L‐rhamnopyranosyl‐(1→2)]‐β‐D‐glucopyranoside (XII) were isolated and characterized from the stems of Paris formosana Hayata (Liliaceae).
Proximate Determination of Triterpene Glycosides in Glycyrrhizae Radix by Ion Exchange Chromatography and Turbidimetry
Authors: Chen Sheng‐Chih , Li Han‐Teh
Published: June 2015

A simple method for the proximate determination of triterpene glycosides in glycyrrhiza was developed. Glycyrrhiza extract was directly chromatographed on SP‐Sephadex C‐25 (H+) and QAE‐Sephadex A‐25 (Cl−) with distilled water and 0.2 M sodium chloride (pH 13.50) as the eluents, respectively. The eluate was then hydrolyzed with perchloric acid and determined turbidimetrically at 530 nm.

With this method, glycyrrhiza samples collected in Taiwan and Singapore were found containing 17.21±0.45% and 7.49±0.35% of triterpene glycosides, calculated as glycyrrhizin, respectively.
Zirconium(IV) Thorium(IV) and Dioxouranium(VI) Complexes of Salicylidene o‐Aminobenzothiol
Authors: Agrawal A.K. , Agrawal Sanjeev , Agrawal Neeta , Kansal B.D.
Published: June 2015

Salicylidene‐o‐aminobenzothiol and its 5‐chloro and 5‐bromo derivatives, dibasic tridentate Schiff bases, dervied from the condensation of o‐aminothiol and Salicylaldehyde, 5‐chloro salicylaldehyde and 5‐bromo salicylaldehyde, were used for coordination with Zr(IV), Th(IV) and UO2(VI) metal inos. The I:I (metal‐ligand) stoichiometry of these complexes is shown by elemental analysis and conductometric titrations. Molecular structure of these complexes are proved by Infra‐red spectroscopy and thermogravimetric analysis. Magnetic susceptibility measurements of Zr(IV), Th(IV) and UO2(VI) complexes show their diamagnetic and octahedral geometry. Results show that all the complexes have solvent molecules in coordination with metal ion.
Crystal and Molecular Structure of the Macrocyclic Nickel (II) Complex Ni(C22H22H4): Dibenzo[b, i][5, 7, 12, 14] Tetramethyl [1, 4, 8, 11] Tetraazacyclotetradeca‐2, 4, 7, 9, 12, 14‐Hexaeneatonickel (II)
Authors: Wang Yu , Peng Shie‐Ming , Lee Yu‐Lin , Chuang Mei‐Chen , Tang Chia‐Pin , Wang Chiu‐Jane
Published: June 2015

The crystal and molecular structure of the four‐coordinate complex Ni(C22H22N4) containing the tetramethyldibenzotetraaza[14] annulene ligand has been determined from three‐dimensional X‐ray diffraction data. The complex crystallized in the monoclinic space group C2h5‐P21/n with cell dimensions a=14.7967(10), b=11.2169(6), c=11.4510(6) Å, and β=98.467(5)° with Z=4. The final agreement indices from the least‐square refinement of 245 variables with 3111 observations F>3σ(F), are R=0.050, Rw=0.037. The structure has a pronounced saddle‐shaped conformation with Ni atom at the saddle point coordinated to four nitrogen atoms. The average Ni‐N distance is 1.866(3) Å. The delocalized propane‐1,3‐diiminato chelate rings and the benzene rings are linked by nominally single C‐N bonds.
Superheating Limit of Boiling n‐Hexane Spinodal Decomposition Versus Nucleation Process
Authors: Yang Chan‐Lon , Mou Chung Yuan
Published: June 2015

Two predicative theories for superheating limits of a boiling liquid are considered in this work. In the nucleation picture, classical homogeneous nucleation theory is used to calculate superheating temperature at various pressures. In spinodal decomposition picture, stability limits are taken as the superheating temperature. A perturbed‐hard chain equation of state was developed and used for the purpose of calculating mechanical stability limit. Calculations are done for the case of normal hexane at different pressures and compared with experimental results. Classical nucleation theory gives good prediction at negative and smaller pressures. While near critical pressure, spinodal picture seems to be more accurate.
Dynamic NMR Studies of Some Halo and Mercaptide Bridged Palladium (II) Dimers
Authors: Lin Ivan J. B.
Published: June 2015

Some halo or mercaptide bridged palladium (II) dimers, [Pd(S2CNR2)X]3 (R=ibutyl, X=Cl, Br, I, S‐ethyl and S‐t‐butyl) were studied by variable temperature 1H nmr spectroscopy. Line shape changes of the chloro and bromo bridged dimers were interpretated by the solvolytic breaking of the Pd‐X bond, while mercaptide bridged complexes were explained in terms of slow N‐C single bond rotation. The results consist with the strengthness of the class b metal ion with various soft donor ligands.
Sydnone Compounds. XX. The Synthesis and the Schmidt Reaction of 4‐Formyl‐3‐Arylsydnone
Authors: Yeh Mou‐Yung , Tien Hsien‐Ju , Huang Llng‐Yuang , Chen Meng‐Hsin
Published: June 2015

A convenient method to prepare 4‐formyl‐3‐arylsydone (I) from 3‐arylsydnone by the Vilsmeier reaction in moderate yields (30%‐76%) was carefully investigated.

According to the Schmidt reaction, I reacts with sodium azide in concentrated sulfuric acid to produce 3‐arylsydnone‐4‐carboxamide (II). But 3‐arylsydnone‐4‐carhonitrile (III) is obtained, if dilute sulfuric acid was used instead.

When III treates with concentrated sulfuric acid, II is obtained in good yield. The all possible reaction mechanisms are suggested.
Isomerization of Maleic Acid to Fumaric Acid Catalyzed by Bromate Ion and Bromine
Authors: Chen Yih‐Hsiung , Jwo Jing‐Jer
Published: June 2015

In the presence of a relatively small amount of bromate, maleic acid in aqueous sulfuric acid isomerizes catalytically to fumaric acid in the dark at room temperature. The concomitant presence of a suitable amount of bromine in CCI, phase raises the rate and yield significantly. The yield and rate of isomerization depend on the relative amounts of maleic acid, bromate, bromine, and sulfuric acid. For a favorable condition, nearly 90% yield can be obtained. Raising the temperature accelerates the production of fumaric acid while decreases the final yield. The isomerization reaction competes favorably with the redox reaction at room temperature while the latter dominates at high temperature. For the heterogeneous case, the agitation of the reaction mixture delays the isomerization. The presence of cumene or benzene inhibits the isomerization. Hypobromous acid is proposed to play a major role in catalyzing the isomerization. A mechanism is proposed to rationalize the experimental results.
Synthesis of 6,9‐Dipropyl‐1,4‐Dioxaspiro[4.5] Deca‐6,8‐Diene‐2,10‐Dione and its Diels‐Alder Reactions with Substituted Acetylenes
Authors: Liao C. C. , Lin H. S.
Published: June 2015

The title compound, a masked 3,6‐di‐n‐propyl‐o‐benzoquinone, was synthesized from 3,6‐di‐n‐propylcatechol in 82% yield. Its Diels‐Alder reactions with methyl propiolate, phenylacetylene, 1‐octyne, dimethyl acetylenedicarboxylate, diphenylacetylene and 3‐hexyne were studied. The yields of the adducts were excellent except for the last two cases in which the unimolecular decomposition of the title compound to generate 3,6‐di‐n‐propylcatechol methylene ether predominates. The regiochemistry of the adducts derived from monosubstituted acetylenes were determined by the correlation of 13C chemical shifts of the adducts and the corresponding bicyclo[2.2.2]octa‐5,7‐diene‐2,3‐diones obtained from the hydrolysis of the spirolactone ring of the Diels‐Alder adducts. Photolysis of these α‐diketones gave the corresponding aromatic compounds in high yields. These synthetic sequences provide an effective entry to bicyclo[2.2.2]octa‐5,7‐diene‐2,3‐diones and polysubstituted benzene derivatives.
Isomerization of Maleic Acid to Fumaric Acid Catalyzed by Cerium(IV) and N‐Bromo Compounds
Authors: Jwo Jing‐Jer , Chen Yih‐Hsiung , Chang Eng‐Fen
Published: June 2015

Maleic acid (MA) in aqueous sulfuric acid undergoes catalytic isomerization in the presence of small amounts of Cerium(IV) ion and N‐bromosuccinimide (NBS) or N‐bromoacetamide (NBA). The rate of isomerization is very fast even at room temperature and the yield is quite acceptable. The rate of isomerization depends on the relative amounts of MA, Ce(IV), NBS, NBA, and H2SO4. However, maleic acid has greater effect on the final yield. Sulfuric acid exhibits more chemical effect than physical effects. The competitive redox reactions of Ce(IV), NBS, and NBA with MA limit the yield of isomerization to about 85%. In the vicinity of room temperature, a raise of five degrees in temperature nearly doubles the rate of isomerization. Acrylamide shows inhibitive effect on the isomerization. The rate of hydrolysis of NBS or NBA in aqueous acidic solution depends on the concentrations of hydrogen ion, and NBS or NBA itself. The rate of hydrolysis of NBA is much faster than that of NBS. Mechanism involving bromine atom as catalyst is proposed to explain experimental results.
Polarographic Behaviour and Determination of Kinetic Parameters of Lead‐Pamoate Complex in Dimethyl Sulfoxide
Authors: Kao Chen‐Feng , Guo Chin‐Cherng , Lai Tsai‐Teh
Published: June 2015

The polarography of lead ion in dimethyl sulfoxide (DMSO) was investigated in the DMSO concentration range 0–80 vol.%. The complex species identified were Pb2(DMSO)4+3, Pb(DMSO)2+3 and Pb(DMSO)2+6 in [DMSO]<10 vol.%, 10< [DMSO]<43 vol.% and [DMSO]>43 vol.%, respectively. In the presence of pamoic acid, the reduction of lead ion in DMSO was two‐electron reversible diffusion‐controlled at pH≤6.0, but it became irreversible at pH>6.0. The complex species identified was Pb(Dm)2(Pm)3(OH)6− at pH>6.0. The rate constants of electro‐reduction and electro‐oxidation, activation energies were determined. The hydrolysis constants of lead ion in dimethyl sulfoxide concentration 40–70 vol.% at pH 4.5–6.0 were found to be of the order of 10−6. The stability constants of the Pb(DMSO)2+3 and Pb(DMSO)2+0 were also determined to be of the orders of 101 and 105, respectively.
Kinetics of Phase Transfer Catalytic Preparation of Benzyl Benzoate
Authors: Chang Jen‐Ray , Yeh Mou‐Yung , Shih Yen‐Ping
Published: June 2015

The kinetics is studied for the phase transfer catalytic preparation of benzyl benzoate from sodium benzoate and benzyl chloride with tetrabutylaramonium iodide as catalyst in a well stirred batch reactor. Benzyl chloride is dissolved in toluene as the organic phase and sodium benzoate is dissolved in water as the aqueous phase. The kinetics of the overall reaction is described by a first‐order model based on the concentration of benzyl chloride in the organic phase at the later time of the batch reaction. The rate constant increases with an increase of the catalyst concentration while decreases slightly with an increase of the concentration of sodium benzoate under the experimental condition.
Mössbauer Spectroscopic Studies of Bromostannate(II) Complexes in Frozen Aqueous Solutions
Authors: Hsu C. M. , Cheng H. S. , Luh H. , Chen M. Y.
Published: June 2015

Mössbauer spectra of KSnBr3·2H2O were very broad and could not fit Lorentz equation, suggesting unresolvable quadrupole doublets. Its quadrupole splitting was estimated to be about 0.25 mm/s from the separate experiments on frozen aqueous solutions of Sn(II)‐Br− systems. Stability constants of bromostannate(II) complexes were determined at μ = 3.5 from the Δ‐cL curve by the approximation method, which were in agreement with the literature values.
Quinaldic Acid Complexes with Some Trivalent Rare Earth Metals
Authors: Abou Ali S. A. , Hindawey A. M. , Mohamed G. B.
Published: June 2015

The Polarographic behaviour of quinaldic acid in the presence of lanthanide cations (Kd3+, Gd3+, Er3+) is studied at pH=4.5 and 0.1 M HClO4 as supporting electrolyte. The polarographic reduction gives two waves at lower concentrations of quinaldic acid and three waves at higher concentrations. The nature of the waves was investigated. The dissociation constant of quinaldic acid as well as the stability constants of some lanthanide cation complexes with quinaldic acid were determined potentiometrically in 75% (v/v) dioxane‐water at 25°C and 0.1 M KNO3. The solid complexes of Nd, Gd and Er were isolated and studied by ir, differential thermal analysis (DTA) and thermogravimetric analysis (TGA) techniques.
Analysis of Non‐Exponential Multi‐Component Emission of Aryl Ketones: The Cases for the Phosphorescence Spectra of Beta‐Naphthil and Benzophenone
Authors: Chow Tahsin J. , Marshall Wilson R.
Published: June 2015

The dual emission spectra of β‐naphthil in two different glasses at 77° K have been resolved to their individual components by a computerized kinetic phosphorescence spectrometry system. Both the time‐resolved spectrum which reveals the kinetic behavior of the excited states and the wavelength‐resolved spectrum which tells the nature of the emitting species are obtained. Several possible emission mechanisms are discussed based on the informations gathered through the resolution processes. Triplet‐triplet annihilation is shown to exist in solutions of benzophenone as well as in solutions of β‐naphthil. As concluded from the results of time‐resolved study, such kind of interaction is responsible for the non‐exponential distorsion of the decays. And according to the wavelength‐resolved studies, transoid and cisoid conformational isomers seem to accout for the sources of the dual emission of β‐naphthil.
Numerical Calculation of the Electrostatic Potential Around an Ionic Micelle with Counter Ion Binding
Authors: Lee Sze‐Tsen , Mou Chung Yuan
Published: June 2015

A numerical solution of the nonlinear Poisson‐Boltzmann equation (PBE) is presented for a system of spherical micelles with counterfoil binding. The approach investigates the following effects on ion micelle interactions, (i) total surface charge, (ii) competitions of different counter ions on micellar surfaces and (iii) surface potential determination. The theory is applied to interpret the ion activities in micellar solution as measured by ion‐selective electrodes.
Photochemical Reaction of Decacarbonyldirhenium with Thiophene and Crystal Structure of Tetradecacarbonylhydridotrirhenium
Authors: Yang C.S. , Cheng C.P. , Guo L.W. , Wang Y.
Published: June 2015

The photochemical reaction of Re2(CO)10 with thiophene in hexane solution was investigated under vacuum. Three rhenium clusters: H2Re3(CO)12, HRe3(CO)14 and Re3(CO)14(OH)4, were isolated. The structure of Fellmann‐Kaesz cluster Complex HRe3(CO)14 was determined by use of the X‐ray diffraction method. The three rhenium atoms form a plane of symmetry and L: Re1Re2Re3 is 107°. The ten carbonyl groups bonded to the two terminal rhenium atoms Re1 and Re3, are staggered with respect to the central rhenium atoms. The bond lengths are 3.10 Å for Re2‐Re3 and 3.34 Å for Re1‐Re2. The bridging hydride is between Re1 and Re2.
Cobalt (II) Complexes with Tri‐ and Tetradentate Schiff Bases Derived From 2‐Furyl Glyoxal and Some Amines
Authors: Dhakarey Rajesh , Saxena Greesh
Published: June 2015

Coordination compounds of cobalt (II) with four new schiff bases of furyl glyoxal, 2‐furyl‐methyl‐2′‐carboxylato ketoanil (2 FMCKA), 2‐furyl glyoxal ethyenediimine (2 FGED), 2‐furyl giyoxal‐2′‐sulphonic acid anil (2 FGSAA) and 2‐furyl glyoxal‐2′‐chloro‐4‐nitro anilimimine (2 FGCNA) were prepared and characterised with the help of elemental analyses, magnetic measurements, infra‐red and electonic spectral data. Various ligand field parameters such as 10 Dq, B & C, F2 & F4, f2 & f4, h, B° etc. and transition energies ν1;, ν2 & ν3, were calculated with the help of electronic spectral data. The ν(C=N) bands in the IR spectra of all the ligands are lowered in complexation indicating nitrogen coordination of the ligands. All these studies indicate that cobalt(II) ion is in a distorted octahedral environment.
A Simple Novel Method for the Analysis of Lubricating Oil Additives by the Use of Sep‐Pak Cartridges
Authors: Wu Yi‐Shuen , Yang Mei‐Hui , Lin Ching‐Erh
Published: June 2015

In combination with the use of SEP‐PAK cartridges and computerized difference infrared spectroscopic technique, a simple novel method for analyzing lubricating oil additives was developed. The present method involves solvent extraction and the use of SEP‐PAK C18 for separating polar additives from residual base oil, followed by the use of SEP‐PAK Silica for further elution. With the aid of infrared data station, components of the polar additives were identified. The present method is definitely much more rapid and efficient than the conventional column separation method, and the separation efficiency of this simple method is comparable to that of using flash chromatographic technique.
A Study of the Constituents of the Heartwood of Tsuga Chinensis Pritz. Var. Formosana (Hay.)
Authors: Fang Jim‐Min , Wei Kuo‐Min , Cheng Yu‐Shia
Published: June 2015

By means of spectroscopic analysis, X‐ray crystallography and chemical correlation the heartwood of Taiwan hemlock was found to contain compounds of sterols, carboxylic acids, 13‐epimanool, o methoxyphenolics, coniferaldehyde, benzofuranoid neolignan, α‐conidendrin, tsugacetal, isolariciresinol, secoisolariciresinol, matairesinol, hydroxymatairesinol and oxomatairesinol. Among them (+)‐tsugacetal is a novel lignan acetal having an α‐conidendrin related structure with the acetal methoxy group at the β‐position.
A New Lignan, Cagayanin, from Nutmeg of Myristica Cagayanensis Merr
Authors: Kuo Yueh‐Hsiung , Wu Rong‐En
Published: June 2015

A new lignan, cagayanin, has been isolated from the nutmeg of Myristica cagayanensis Merr. and elucidated as formula (5) by spectral and chemical evidence.
Thermal Diffusion with Chemical Reaction: A Carrier System
Authors: Mou Chung Yuan , Lin Jeong‐Long
Published: June 2015

The heat of transport of oxygen across a membrane mediated by hemoglobin (Hb) as a carrier is iuvestigated by the method of irreversible thermodynamics. It is assumed that oxygen combines with hemoglobin molecules to form oxyhemoglobin according to the reaction nO2 + Hb=HbOzn. The oxyhemoglobin molecule HbOzn then migrates to a new position and is reconverted to Hb by releasing oxygen.

It is shown that the heat of transport of oxygen consists of two contributions; one due to the reaction and the other from thermal diffusion of individual species present. Total oxygen flux across the membrane is also calculated in terms of temperature and the chemical potential difference of oxygen across the membrane. The use of the heat of transport as a measure of the efficiency of the heat pump for the carrier‐mediated transport process is investigated.
Stabilities and Thermodynamic Properties of Ethylenediamine‐di(o‐Hydroxyphenylacetic Acid) Chelates of Tripositive Lanthanide Ions
Authors: Hseu Tong‐Ming , Wu Shwu‐Tzy , Lin Zui‐Feng
Published: June 2015

The interaction between ethylenediamine‐di(o‐hydroxyphenylacetic acid) (EDDHA, H4Z) and tripositive lanthanide ions has been investigated. The formation constants of the protonated chelates (LnHZ) and those of the normal chelates (LnZ−) have been evaluated at various temperatures and at a constant ionic strength of 0.1(KNO1). For LnHZ, the pH‐titrimetric technique, and for LnZ−, the mercury indicator electrode method were used. The enthalpy and entropy changes characterizing the formation of LnZ− have been calculated at 25° and, these functions have been compared with the corresponding values of other lanthanide chelates with related chelating agents.
The Reaction of Triplet State Benzophenone with Acetylacetone
Authors: Chow Yuan L. , Buono‐Core Gonzalo E.
Published: June 2015

Irradiation of benzophenone in acetic acid containing acetylacetone resulted in regiospecific addition to form cis‐2,2‐dihpenyl‐3‐hydroxy‐3‐methyl‐4‐acetyloxetane and the rearrangement products therefrom. In the co‐presence of copper ions, the regiospecificity is scrambled to give these products and a small amount of 1,1‐diphenyl‐1‐buten‐3‐one, the secondary decomposition product of the other oxetane arising from the alternative orientation of the addition.
A Study of the Slow Release of Urea from Microcapsules with TDI as the Wall‐Sealing Treatment
Authors: Wu Jen Chin , Lin Yih Tsung
Published: June 2015

The release of urea from ethylcellulose coated microcapsules was efficiently reduced by post‐treatment with toluene‐2,4‐diisocyanate (TDI) in n‐hexane. Our results show that TDI can be used as a sealant which modifies the shell characteristics of the ethylcellulose film. The modification is rather complicated in that it probably includes cross‐linking between ethylcellulose and TDI, a reaction between urea and TDI, and biuret or polyurea formation from TDI absorbed on the microcapsules surface with moisture. The influence of post‐treated conditions on the release of urea from ethylcellulose shell was studied.
The Simultaneous Determination of Trace Dy, Eu, Gd and Sm in Nuclear Grade Uranium Oxide by Inductively Coupled Plasma‐Atomic Emission Spectrometry (ICP‐AES)
Authors: Wu Cheng‐I , Chang Fu‐Chung , Wang Shieh‐Jun
Published: June 2015

A method for the simultaneous determination of trace Dy, Eu, Gd and Sm in nuclear grade uranium oxide by Inductively Coupled Plasma Atomic Emission Spectrometry has been developed. The process of uranium extraction and ICP/AES optimization are investigated. The detection limits of Dy, Eu, Gd and Sm are 0.003, 0.002, 0.006 and 0.010 μg/ml respectively, and more than 90% recovery can be obtained.
Sydnone Compounds XXX. The Syntheses and Reactions of 3‐Aryl‐4‐Cyanosydnones and 3‐Aryl‐4‐Formylsydnone Oximes
Authors: Yeh Mou‐Yung , Tien Hsien‐Ju
Published: June 2015

In the presence of pyridine, 3‐aryl‐4‐formylsydnone (II) reacts with hydroxyl‐amine hydrochloride to produce 3‐aryl‐4‐formylsydnone oxime (III). This reaction was performed in ethanol solution with reflux or at room temperature; the latter procedure gave an excellent yield (74‐98%) and high purity.

(III) reacts in acetic anhydride at room temperature to give 3‐aryl‐4‐formylsydnone oxime O‐acetate (IV).

A convenient method for the synthesis of 3‐aryl‐4‐cyanosydnone (V) is to dehydrate (III) with acetic anhydride at reflux. When (IV) was refluxed with acetic anhydride, (V) was similarly obtained. Another convenient method to prepare (V) from (III), dehydration with thionyl chloride at room temperature, was also investigated.
Conformational Studies on Polytripeptides as a Model of Collagen
Authors: Kawai Tohru , Toba Shigeru , Ebert Gotthold , Chang Teh‐Chou
Published: June 2015

To study the role of glycine residues in stabilizing the collagen triple helix, the glycine residues in the polytripeptide (Pro‐Ala‐Gly)n were partially replaced by alanine. The proline content was kept constant. The stability of the helical conformation of these polypeptides was studied by IR‐ and X‐ray measurements in the solid state and by ORD, CD and viscometry in solution. The renaturation was followed as a function of time. All the polytripeptides studied, with the exception of (‐Pro‐Ala‐Ala‐)n attained the polyproline II conformation. However the stability decreased with increasing alanine content. Obviously the molecules of (‐Pro‐Ala‐Gly‐) are highly associated by intermolecular hydrogen bonds and one may therefore suppose that a triple‐stranded helix aggregation occurs. The results of the refolding process show that the stability of the helices seems to also affect the refolding rate in terms of the optical rotation, Two transitions appeared: the first one is responsible for a rapid reversible change in conformation and the second one for a further slow and irreversible change in the hydrodynamic shape. The latter seems to be due to the partial helical nature, leading to higher chain mobility.
Matrix‐Assisted in‐Beam Mass Spectra of Thermally Fragile Molecules
Authors: Liu Lilian Kao , Hsieh Tsing‐Pai
Published: June 2015

In‐beam and matrix‐isolation techniques have been used in the mass spectral studies of several categories of biologically significant compounds. These include amino acids, quaternary ammonium salts, vitamins and nucleosides. Molecular ions and/or (M+H)+ions are obtained, together with useful fragmentations, all of which are valuable in structural elucidations. Spectra obtained by this version of the in‐beam technique are similar but not identical with those obtained by field desorption and secondary ion mass spectrometry. Ammonium and sodium chlorides, ammonium sulfate, p‐toluenesulfonic and hydrochloric acids can all be used as a room temperature matrix. The detection limits for vitamin E and 2′‐deoxyguanosine have been determined as 1 ngand 5 μg, respectively.
A Theoretical Analysis of Single Drop Square‐Wave Polarography
Authors: Hwang Jin‐Yih , Wang Yung‐Yun , Wan Chi‐Chao
Published: June 2015

The peak current response to single drop square‐wave polarography (SDSWP) is developed based on a spherical diffusion model. It is found that the equation originally developed by Ramaley et al. based on a planar diffusion model is only a special case of the generalized model.
Spectrophotometry Determination of Copper and Palladium Using Some 1,3,5‐Triphenylformazans
Authors: El‐Ansary A. L. , Issa Y. M. , Hanna Z. F.
Published: June 2015

A new rapid and accurate method for the spectrophotometric microdetermination of Cu(II) and Pd(II) using some 1,3,5‐triphenylformazans (I) is given. The optimum conditions for the formation of the complexes are extensively investigated. The ligands form 1:1 and 1:2 (M:L) complexes with Cu and Pd ions, Beer's law is obeyed up to 3.8 and 6.5 ppm Cu and Pd respectively. The influence of foreign ions is investigated. The ligands were used successfully as indicators in spectrophotometric titration of Cu and Pd ions with EDTA and CDTA.
Syntheses and Diel‐Alder Reactions of Bis(Alkylidene)Cyclohexanes
Authors: Tso Hsi‐Hwa , Liu Lee‐Tai , Lin Lung Chin , Chou Ta‐Shue
Published: June 2015

Substituted cyclohexene‐fused 3‐sulfolenes have been prepared by the direct deprotonation/alkylation reactions of a readily available starting material. These fused 3‐sulfolenes undergo inter‐ and intramolecular Diels‐Alder reactions at high temperatures to give properly substituted bi‐ and tricyclic molecules.
Transition Metal Complexes of an Antipyrine Derivative
Authors: Shoukry Mohamed M. , Elmoghayar Mohamed R. H. , Ibraim Mohamed K. A. , Elghandour Ahmed H. H.
Published: June 2015

The stepwise formation constants of N‐antipyrinyl‐N′‐3‐phenyl‐2‐propenoyl‐thiourea (I) complexes with metal ions of the first transition series, Cu(II), Ni(II), Co(II), Mn(II) and Zn(II) have been determined in 70% (V/V) ethanol‐water medium. The formation constants for the chelates follow the Irving‐Williams series:

Zn(II)Ni(II)>Co(II)>Mn(II)

The effect of ionic radius and electronegativity on the chelate formation are discussed. Complexes of Cu(II) and Ni(II) have been synthesised and characterised by elemental analysis, electrolytic conductance, IR spectra and magnetic susceptibility measurements. The ligand forms bis‐complexes with Cu(II) and Ni(II). The binding sites are oxygen and sulphur atoms.
The Reduction and Nitration of 1‐Keto and 4‐Keto‐1,2,3,4‐Tetrahydrophenanthrene
Authors: Zee Sheng‐Hsu , Lu Chin‐Kun
Published: June 2015

The reduction and nitration of 1‐keto and 4‐keto‐1,2,3,4‐tetrahydrophenanthrene were investigated. The structures of the products were confirmed by spectroscopic data.
Effect of Structure on Excess Partial Volumes and Deviation in Molar Viscosity of Some Aqueous‐Ethylene Glycols Mono Alkyl Ether
Authors: El‐Harakany A. A. , Hafez Amina M. , El‐Laboudy A. S.
Published: June 2015

The data obtained for density, viscosity, and dielectric constant are used for the study of the physical properties of 2‐ethoxy ethanol‐water mixtures. Density measurements showed the presence of contraction in the volume of the mixture and also in the partial molal volume of the components. Viscosity data provided supporting evidence of interaction between the two solvents. The dielectric data for the system were studied in terms of a deviation fraction, δD, representing the deviation from an ideal volume mixture. The results are also compared with the data obtained in the literature for water‐2‐methoxy ethanol and water‐ethylene glycol mixtures.
The Synthesis of p‐Methoxybenzyloxycarbonyl Amino Acids
Authors: Chen Shui‐Tein , Weng Chih‐Shyong , Wang Kung‐Tsung
Published: June 2015

o‐Chlorobenzyloxycarbonylimino‐2‐phenylacetonitrile (Cl‐Z‐ON) and p‐methoxybenzyloxycarbonylimino‐2‐phenylacetonitrile (MOZ‐ON) have been prepared from 2‐hydroxyimino‐2‐phenylacetonitrile (oxime), phosgene, and the corresponding alcohols. Cl‐Z‐ON is synthesized for the first time and found to be stable at room temperature. MOZ‐ON is utilized for the preparation of MOZ‐amino acids under various conditions. The oxime can be recovered and reused. The combination of Cl‐Z‐ and MOZ‐ for the alternative masking of the N4‐ and N4‐amino groups of lysine residue has also been studied.
Five New Sesquiterpenes from the Heartwood of Juniperus Squamata Lamb
Authors: Kuo Yueh‐Hsiung , Yang I‐Chang , Chen Chun‐Shing , Lin Yau‐Tang
Published: June 2015

Extracts of the heartwood of Juniperus squamata Lamb. var. morrisonicola (Hay.) Li and Keng contain the known constituents 8,14‐cedranoxide, 8,14‐cedranolide, cedrol, β‐sitosterol, widdrol, 7‐oxototarol, procerin, 8,14‐cedranediol, hinokiol, sugiol, hinokiic acid, cedrolic acid, and five new sesquiterpenoids, epicedranediol, 4‐ketocedrol, 3β‐hydroxycedrol, isocedrolic acid, and β‐chamigrenic acid. These new sesquiterpenes were identified by spectroscopic data and chemical correlations.
The Stabilities and Thermodynamic Properties of Triethylenetetraminehexaacetic Acid Chelates of the Tripositive Lanthanide Ions
Authors: Hseu Tong‐Ming , Chang Chun‐Chih , Lin Zui‐Feng
Published: June 2015

The interaction between the decadentate ligand triethylenetetraminehexaacetic acid (TTHA or H6Z) and tripositive rare‐earth metal ions (Ln3+) has been investigated. The acid formation constants of the hydrogen chelates (LnHZ2−, LnH2Z‐) and the formation constants of the normal chelates (LnZ3−) have been evaluated at 15, 25 and 35°C, and at an ionic strength of 0.1 (KNO3), the former by a titration method and the latter by a mercury indicator electrode technique. Enthalpy and entropy changes characterizing the formation of the normal chelates have been calculated at 25°C. These functions have been compared with corresponding values for related chelating agents.
The Chemical Constituents of the Liverwort Mylia Nuda
Authors: Wu Chia‐Li , Asakawa Yoshinori
Published: June 2015

Two diterpenoids, (+)‐labda‐7,14‐dien‐13‐ol and (+)‐manoyl oxide, and one bis(bibenzyl) compound, isomarchantin C, were isolated as the major components from the Taiwanese liverwort Mylia nuda. The spectral evidence is discussed in this paper. In addition, several monoterpenes and sesquiterpenes were also identified by GC/MS.
Characterization of Hydrogen Adsorption on Palladium and Pd/c Using a Radiotracer
Authors: Loh Kuo‐Liang , Tang Yi‐Noo
Published: June 2015

Hydrogen adsorption on palladium black and palladium supported on activated carbon was characterized by the Temperature Programmed Desorption technique (TPD) using the radiotracer tritium. It is shown that there are five energetic desorbed hydrogens with peak maxima at —50, 35, 115, 350, and 580°C. An additional peak at — 120°C hydrogen desorbed from activated carbon was observed on Pd/C. An isotopic hydrogen separation experiment was designed to demonstrate that hydrogen only dissociatively adsorbed on palladium surfaces whereas it was associatively adsorbed on activated carbon.
Polarization Resistance Study on Copper Corrosion in Aqueous Potassium Hydrogen Phthalate Solution
Authors: Mouhad M. Y. , Bekheet A. M. , Soliman S. A.
Published: June 2015

The effect of temperature on corrosion of copper in 0.1 M aqueous solution of potassium hydrogen phthalate (KHPh) has been investigated using polarization resistance technique. it was found that that the corrosion rate in the range 25–65°C obyes Vant Hoff's and Arrhenius Laws. The results indicate that corrosion of copper in KHPh is mainly cathodically controlled process. The polarization resistance decreases with rising the temperature in accordance with Stern‐Geary equation.
Foam Separation of Stannous Ion from Aqueous Solution
Authors: Ferng Tian‐Fwn , Tzuoo Jong‐Jonq , Huang Shang‐Da
Published: June 2015

Sn(II) was removed from solution using various foam separation techniques. It was found that Sn(II) could be effectively removed by adsorbing colloid flotation using either Fe(OH)3 or Al(OH)3 as the adsorbing colloid. Over 99% of the Sn(II) was removed from a solution initially containing 50 ppm Sn(II).
Polarographic Studies of Dithiodiacetic Acid and the Uranyl‐Dithiodiacetic Acid Complex
Authors: Kao Chen‐Feng , Chang Tsong‐Dsu , Lai Tsai‐Teh
Published: June 2015

The polarographic behaviour of dithiodiacetic acid and that of U(VI) in a solution containing dithiodiacetic acid as complexing agent have been investigated.

For the dithiodiacetic acid system, two waves appear over the pH range studied. The prewave is kinetic in nature and the mainwave is diffusion‐controlled. However, as U(VI) is added into the dithiodiacetic acid system, the polarogram changes due to the existence of a complex. The current‐potential curve of the first wave is not the normal S shape. This is due to the superposition of the first wave of the ligand and the wave due to the reduction of the U(VI) in the complex to U(V). The second wave is due to the reduction of the complex

The first wave is an adsorption‐controlled current and the second wave is partly diffusion‐controlled and partly adsorption‐controlled.

We propose an electrode reaction mechanism for both systems and the complex species. The dissociation constant of the complex HASSAUO+2 is found to be of the order of 10−4.
Polycyclic Aromatic Hydrocarbons Formation from Fuel and Additives Combustion
Authors: Sye Wen‐Fa , Lin Chyi‐Lian , Yen Ding‐Ping , Tsai Chang‐Shou
Published: June 2015

A study has been made of the effect of additives to the fuel of a turbulent diffusion flame on the formation of soot and polycyclic aromatic hydrocarbons (PAHs). Fuels containing a polystyrene thickener doped with benzene proved to have many advantages over unthickened fuels. Most significant were an increase in the burning time and the flash point. Nevertheless, polystyrene and benzene additives to a considerable extent increased the formation of soot and PAHs. The analysis of PAHs in this study was made by capillary gas chromatography (GC) and capillary gas chromatography/mass spectrometry (GC/MS). A total of 42 individual compounds were characterized by their retention indices and mass spectra.
The Polarographic Behaviour of Bromate Ions in Buffered and Unbuffered Solutions and the Effect of Surface Active Substances
Authors: Kamal M. M. , Temerk Y. M. , Ahmed M. E.
Published: June 2015

The polarographic behaviour of bromate ions in buffered and unbuffered solutions has been studied in the absence and presence of cationic, anionic and nonionic surfactants. The mechanism for the reduction in acid media is discussed. The adsorption effects of electrochemically inactive surfactants on the polarographic waves of BrO3− has been investigated. The values of the kinetic parameters for the electrode reaction at different pH values have been computed.
Kinetic Study of the Substitution Reactions of Benzyl Halides and Halide Ions in Acetone
Authors: Lin Szu‐Ning , Jwo Jing‐Jer
Published: June 2015

The kinetics of the Finkelstein reactions of benzyl halides and halide ions in dry acetone was studied by using the GC and HPLC methods. The method of conductivity is used to measure the degree of dissociation of alkali halide in acetone. The dissociation of the salt and the common‐ion effect were used to correct the halide ion concentration. Let kxx′‐ and Kxx′‐ represent the corrected second‐order rate constant and equilibrium constant for the PhCH2X‐X′‐ reaction, respectively, then at 25° kxx‐−= 1.83x×10−3 M−1 s−1, KII‐=4.48×104, kBrcl‐=0.377 M−1 s−1, KBrcl‐=874; and kBr‐=7.88 M−1 s−1, KIBr‐=19.2. The entropy of activation is always negative which implies that the activated complex is more solvated than the reactants. There is a good correlation between the enthalpy of activation and the C‐X bond energy. The enthalpy of activation is much smaller than the corresponding C‐X bond energy which implies that both the bond formation and the bond dissociation are taking place simultaneously in the transition state. A modified Taft equation is used to correlate the Finkelstein reactions of alkyl halides (RCH2X). However, the benzyl halides can not be fit by the correlation equation due to the strong electrical polar effects. Discussion of the Finkelstein reactions of organic halides in terms of rate constants, equilibrium constants, solvent effects, and the thermodynamic parameters is also presented.
Synthesis and Surface Acidity of Alpo4–5 and Sapo–5 Molecular Sieves
Authors: Yang Sze‐Ming , Wu Shiaw‐Tzong
Published: June 2015

Aluminophosphate molecular sieves, AlPO4 − 5 and SAPO−5, were synthesized and characterized by XRD, SEM, 29Si and 13C NMR, and TGA. Ammonia TPD indicates the moderately acidic nature of SAPO−5 and the non‐acidic nature of AlPO4−5. The activity of the cumene cracking reaction at 350°C for SAPO−5 is similar to that of LaY, while AlPO4−5 and amorphous AlPO4 show no activity.
Application of Dual Laser Ionization to Trace Analysis of Sodium in A Flame
Authors: Lin King‐Chuen , Duh Yin‐Shing , Sheu Ti‐Ching , Hsu Tzu‐Jeng
Published: June 2015

Dual laser ionization (DLI) is a technique which can be used to detect trace elements in a flame by ionizing the analyte via a dual‐laser stepwise excitation. As a powerful method for flame diagnostics, DLI can detect trace amount of Na at a concentration of ppb (ng/mL), more sensitive by two orders of magnitude than laser‐enhanced ionization (LEI), in which only single laser is used. To demonstrate its potential in trace analysis, we compare the detection limit of DLI for Na with other methods utilizing LEI, atomic emission and laser atomic absorption.
Studies on the Diisocyanate‐Modified Polyvinyl Alcohol Reverse Osmosis Membranes
Authors: Hsieh Kuo‐Huang , Hsu Shan‐Hui
Published: June 2015

The hydroxyl group in polyvinyl alcohol (PVA) membranes had been partially reacted with diisocyanates such as 4,4′‐diphenylmethane diisocyanate (MDI) or the prepolymers containing different functional groups. The transport properties toward water and salt and the stress‐strain properties of these modified membranes were investigated.

The results showed an improvement in salt rejection and a considerable increase in the wet strength of the modified membrane. The water absorption and permeabilities of these modified membranes depended largely upon the functional groups introduced into them.
Synthesis of Amrinone, A Cardiotonic Agent
Authors: Shiao Min‐Jen , Shieh Puh , Lai Jen‐Shiow
Published: June 2015

A new synthesis of amrinone, 1, from 5‐(4‐pyridinyl) −2(1H)‐pyridone, 5, is reported. Nitration at C‐3 of the pyridone ring of 5 followed by reduction afforded amrinone. Another synthetic route was also carried out by bromination at C‐3 of the pyridone ring of 5 followed by substitution with sodium azide to give the corresponding azide compounds 8 which was reduced to amrinone.
Substitution‐Inert Metal Complex Mobile Phases in Non‐Suppressed Cation Chromatography
Authors: Chang C. Allen , Woodhouse Tamar E. , Wu Qihui , Sheu Ceshing , McManus Katherine
Published: June 2015

Substitution‐inert metal complexes, [Co(edda)(H2O)2]+, (Co(edda)(en)]+, [Co(edda)(dmen)]+, [Co(en)2‐(gly)]2+, [Co(en)2(acac)]2+, and [Co(trien)(gly)]2+ in their nitrate salt solutions are used as eluents in nonsuppressed cation chromatography (where edda = ethylenediamine‐N,N′‐diacetic acid, en = ethylenediamine, dmen = N,N′‐dime‐thylethylenediamine, gly = glycine, acac = acetylacetone, and trien = triethylenetetraamine). It is found that all the mono‐ and di‐valent charged complexes can be used to separate alkali and alkaline earth metal cations, respectively. The separations for monovalent cations are sometimes comparable to those using ultrapure HNO3 solutions. However, the divalent Ca2+ and Sr2+ ions cannot be resolved using the metal complex eluents. On the other hand, a selected, direct non‐suppressed IC separation of zinc(II) and cadmium(II) ions is demonstrated for the first time using a substitution‐inert metal complex eluent and a conductivity detector. Comparisons of these eluents with those reported previously, i. e. HNO3 and ethylenediammonium salt solution are made and explanations are proposed to account for the different selectivities observed where possible. The future development of this technique is also briefly discussed.
Investigating the New Interaction Model between Cu(II) and PVA by the Proton Relaxation Method
Authors: Chen Jyh‐Horung , Hwang Lian‐Pin
Published: June 2015

An aqueous PVA‐Cu2+ solution at pH = 3 is in the hydrated form and becomes green at pH ⩾ 6 with a decrease in viscosity. The structure of the copper ion is suggested to be that of a polynuclear complex at pH > 6. For the green solution the polynuclear chains of the copper complex are believed to be surrounded by the PVA chains with the hydrophobic backbones facing toward the inside and the hydrophilic OH groups oriented toward the outside facing the bulk water. The proton spin‐lattice relaxation rate 1/T1p and the spin‐spin relaxation rate 1/T2 of CH and CH2 in PVA and H2O for aqueous PVA‐Cu2+ solutions at pH = 3, can be explained by the two site exchange model in the region of the fast exchange limit. The dipolar correlation time τc is dominated by the reorientational process with a dipolar correlation time of 2.11 × 10−11 s. When the pH rises from pH=3 to pH=12.5, the variation of 1/T1p and 1/T2p of CH and CH2 in PVA with Cu2+ ion concentration in aqueous PVA‐Cu2+ solution at pH=12.5 can be explained in terms of the relaxation by an inclusive model of the polynuclear copper complex and PVA. Furthermore, the frequency (or field) dependence of 1/T1p, 1/T2p of CH in PVA for aqueous PVA‐Cu2+ solution at pH = 12.5 suggests that the dipolar relaxation is dominated by the electron‐spin relaxation with the electron spin relaxation time T1e = 1 ˜ 2 × 10−10 s. The invariance of 1/T1p and 1/T2p of H2O with the variation of the Cu2+ ion concentration in aqueous PVA‐Cu2+ solution at pH = 12.5 supports the hypothesis that the water is not directly bound to the Cu2+ ion.
Some Reactions with 3‐(2‐Chloro‐7‐Methylquinolinyl) Chalcone Derivatives
Authors: Fathy N.M. , Aly A.S. , Abdel‐Motti F. , Abdel‐Megeid F.M.E.
Published: June 2015

The preparation of some new 3‐quinolinylchalcone derivatives was described. Their reaction with hydrazines, hydroxylamine hydrochloride, malononitrile and ethyl cyanoacetate gave the corresponding pyrazoline, isoxazoline, cyanopyridine and cyanopyridone derivatives, respectively. The biological activity of some of the products was evaluated.
Dehydrobromination and Debromination Reactions of Cyclic Dibromosulfones
Authors: Chou Ta‐Shue , Chen Mei‐Man
Published: June 2015

The dehydrobromination and debromination reactions of some α, β‐dibromosulfones in a five‐membered ring with sodium phenylthiolate, pyridine, and sodium methoxide have been studied. In general, phenylthiolate induces debromination elimination reactions while pyridine and methoxide induce dehydrobromination reactions.
Synthesis of Oxidized Derivatives of 10‐Deuterobenzo[A]Pyrene
Authors: Kim Youngmee , Jun Moo‐Jin , Fu Peter P. , Wang Yu‐Kuei , Lai Jeng‐Shiow
Published: June 2015

A series of oxidized derivatives of 10‐deuterobenzol[a]pyrene (10‐D‐BaP) were synthesized. Oxidation of 10‐D‐BaP with sodium dichromate dihydrate yielded the 1,6‐, 3,6‐, and 6,12‐quinones of 10‐D‐Bap. Upon electrophilic aromatic substitution of 10‐D‐BaP with sodium nitrate, N‐bromosuccinimide, and N‐chlorosuccinimide we were afforded 6‐nitro‐10‐D‐BaP, 6‐bromo‐10‐D‐BaP, and 6‐chloro‐10‐D‐BaP, respectively, in high yields. The Vilsmier‐Haack reaction of 10‐D‐BaP provided 6‐formyl‐10‐D‐BaP which upon reduction with sodium borohydride, yielded 6‐hydroxymethyl‐10‐D‐BaP. Reduction with hydrazine in n‐amyl alcohol gave 6‐methyl‐10‐D‐BaP. Reduction of 6‐nitro‐10‐D‐BaP with hydrazine and Pd/C yielded 6‐amino‐10‐D‐BaP. The synthesized compounds, which are known metabolites of benzo[a]pyrene and are useful substrates for metabolism, are important compounds for mechanistic study of the chemical carcinogenesis by benzo[a]pyrene.
Structure of Complex Natural Anthocyanins
Authors: Goto Toshio
Published: June 2015

We proposed four types of stabilization mechanisms of anthocyanin in aqueous solutions; (1) self‐association, (2) copigmentation, (3) intramolecular sandwich‐type stacking, and (4) metal chelation associated with self‐association and copigmentation. The driving force of these stackings would be mainly hydrophobic interactions between the aromatic nuclei which are surrounded by hydrophilic sugar moieties.
An Improved Preparation of Polymer‐Type η3‐Allylpalladiumchlorides
Authors: Lin See , Boudjouk Philip
Published: June 2015

Five polymer‐type new compounds‐(η3‐cyclopentadienyl)palladiumchloride (6), (η3‐indenyl) palladiumchloride (7), (η3‐cycloheptatrienyl)palladiumchloride (8), (η3‐phenalenyl)palladiumchloride (9) and (1,2,3‐η3‐4,5,6,7‐η4‐cyclopheptatrienyl)(palladium‐chloride)(tricarboryl Iron) (10) have been prepared from the reaction of Na2PdCl4 with 1‐trimethylsilylcyclopentadiene (1), 1‐trimethylsilylindene (2), 1‐trimethylsilyl cycloheptatriene (3), 1‐trimethylsilylphenalene (4) and 1‐trimethylsilylcycloheptatriene tricarbonyl Iron (5) respectively. All the complexes(6)‐(10) are obtained in excellent yield using the improved preparation route. Furthermore, a reaction mechanism is proposed.
Deformation Density Study of KMnO4
Authors: Wang Yu , Ueng Chuen‐Her , Lee L.W. , Chuang M.C. , Lepage Y. , Gabe E.J.
Published: June 2015

The electron density distribution of KMnO4 is studied by the X‐ray diffraction method. Potassium permanganate crystalizes in an orthorhombic space group Pbnm with cell parameters a=7.3661(7), b=9.0610(9), c=5.6458(3)Å, Z=4. The molecular symmetry is CS with the Mn atom and two oxygen atoms located on the plane perpendicular to the c‐axis. A set of accurate diffraction data were measured at 115K. Subsequent refinements and Fourier syntheses were performed. The electron density distribution is expressed in terms of the deformation density. The Mn‐O bondings are well characterized, the lone pair electron density at the oxygen atoms is also observed. The density near the Mn nucleus seems to be very sensitive to changes of the scale factor and extinction coefficient. Several types of extinction corrections were made. The features of the Mn‐O bond are comparable to the theoretical density calculated at the ab‐initio level, and to the experimental density of the isoelectronic compound K2CrO4. However, the experimental density of KMnO4 is not so well reproduced in the vicinity of Mn nucleus.