016244   Malekfar R;Abassi B (Physics Dep, Faculty of Basic Sciences, Tarbiat Madarres Univ, P.O. Box 14115-175, Tehran, I.R. Iran, Email: Malekfar@modares.ac.ir) : Raman spectra of mono and tri-glycine sulpho-phosphate (MGP & TGSP) single crystals at various H₃PO₄ concentrations. Asian Chem Lett 2006, 10(3-4), 83-8.

A Systematic work under takes dispersive Raman backscattering study of triglycine sulfate, TGS, doped with phosphoric acid, TGSP, and mono-glycine phosphate, MGP, crystals. Modified single crystals of TGSP and MGP with different concentrations of phosphoric acid have been grown from aqueous solutions by the evaporation at constant temperature method. The Raman spectra of as grown crystal surfaces have been recorded and used to characterize the crystals structural changes. The differences in the Raman spectra profiles of TGSP and MGP crystals mainly seem to relate to the changes in CH₂, sulfate and zwitter bonds. Study attempts to implement some analytical guidelines in order to improve the final physical parameters of the TGSP and MGP crystals as raw and sensitive materials for room temperature infrared detectors and pyroelectric thermal imaging systems. Adding phosphoric acid to TGS solution modify the crystal structure and it is not only helpful to grow better TGSP crystals which holds the polarization, but also helps to grow crystals with some larger suitable planes for infrared detectors.

4 illus, 8 ref

016243   Liu X H;Jing-Bai;Qing-Xu;Ren J R;Zao H P;Gao H W (State Key Laboratory of Pollution Control and Resource Reuse, College, Tongji Univ, Shanghai 200092, P R China, Email: emsl@mail.tongji.edu.cn) : Spectrophotometric determination of sodium dodecylbenzene sulphonate using congo red. Indian J chem Technol 2008, 15(5), 488-92.

A new spectrophotometric method is developed to determine sodium dodecylbenezene sulphonate (SDBS) in natural water without the use of organic hydrophobic solvents and two-phase extraction. In BR buffer solution (pH 2.03), SDBS replaces sodium diphcnyl diazo-bis-α-naphthylamine-4-sulphonate (Congo red, CR) in CR-cetylpyridinium chloride (CPC) system. Application of absorbance ratio difference (ARD) to this replacement reaction gives a new spectrophotometric method for the determination of SDBS. The absorbance measurements are made at 590 nm and 469 nm. Results have shown that absorbance ratio difference (ΔA₄) gives linear curve in the range of 3.3 -139.4 mg/L for SDBS. The limit of determination of SDBS (38/k) is 1.1 mg/L. The method has been employed to determine SDBS in natural water with satisfactory results. Relative standard deviation was less than 5%, and the recovery was about 103.7%. The method is comparable to new methylene blue (NMB) method.

4 illus, 2 tables, 19 ref

016242   Kumar S;Garg M;Jodha J S;Singh R P;Pareek N; Chauhan R S;Goswami A K (Chemistry Dep, M.L. Sukhadia Univ, Udaipur-313 001) : Insecticidal activity of some hydroxytriazene derivatives. E J Chem 2009, 6(2), 466-8.

Nine hydroxytriazenes have been synthesized and screened for their insecticidal activity against one day old Drosophila melanogaster Meig (Fruit fly). Out of all the nine compounds screened, 3-hydroxy-3-n-propyl-l-m-chlorophenyltriazene is the most active having LC₅₀ values 0.9847 ppm. The least active compound is 3-hydroxy -3-n-propyl-1-p-methylphenyltriazene, whose values are 16.52 ppm. In general, the LC₅₀ values range from 3.92 to 5.52 ppm.

1 table, 16 ref

016241   Krishnaram H;Ramachandra Mohan M;Naidu A; Savithri M (Zoology Dep, Bangalore Univ, Bangalore-560 056) : Water quality status of lakes of palar river basin, Kolar, Karnataka. Envir Ecol 2008, 26(4), 1462-70.

Water is one of the five elements required for the existence of life. In this study, lakes of Palar river basin were investigated. Most of the lakes like Kolar Amanikere was found to be polluted. The water was not fit for domestic purpose. The other lakes were not polluted, but water could be used for drinking after proper treatment and filtrations.

4 tables, 17 ref

016240   Khanna S;Rastogi V K;Ojha S P (Physics Dep, Ch. Charan Singh Univ, Meerut-250 004, Email: sandeepmanya@rediffmail.com ) : Determination of elemental composition of lead zirconium titanate(PZT) electroceramic doped with samarium. Asian Chem Lett 2006, 10(3-4), 153-6.

Modified PZT samples (pellets) of composition Pb_1-x Sm_x (Zr_0.53 Ti_0.47)O₃ where x = 0.02,0.06 and 0.08 were prepared by conventional solid state reaction method using the oxide precursors. The samples were characterized for their elemental composition by-employing Energy Dispersive X-ray analysis which forms an integrated feature of scanning electron microscope (SEM). The EDAX spectra obtained have identified the elements present in different samples confirming the composition of prepared samples for the study.

3 illus, 3 tables, 8 ref

016239   Khanna S;Ojha S P;Rastogi V K (Physics Dep, Ch. Charan Singh Univ, Meerut-250 004, Email: sandeepmanya@rediffmail.com ) : Dielectric dispersion of samarium modified lead zirconium titanate (PZT) electroceramic. Asian Chem Lett 2006, 10(3-4), 143-7.

Modified PZT samples (pellets) of composition Pb_1-x Sm_x (Zr_0.53Ti_0.47) O₃; where x = 0.02, 0.04, & 0.08 were prepared by conventional solid state reaction method using the oxide precursors. Dielectric dispersion studies are taken on the prepared PZT and PSZT samples.

6 illus, 13 ref

016238   Khana S;Ojha S P;Sharma R;Rastogi V K (Physics Dep, Ch. Charan Singh Univ, Meerut-250 004, Email: sandeepmanya@rediffmail.com) : Influence of samarium on DC conductivity of lead zirconium titanate electroceramic doped with samarium. Asian Chem Lett 2006, 10(3-4), 149-51.

Modified PZT samples (pellets) of composition Pb_1-xx (Zr_0.53Ti_0.47) O₃, where x = 0.02, 0.04, 0.06 and 0.08 were prepared by conventional solid state reaction method using the oxide precursors. The DC conductivity was measured by a three terminal method. The measurements were carried out at various fields and temperatures. It is observed from the conductivity vs temperature plots that conductivity increases with temperature and two distinct regions are present.

4 illus, 11 ref

016237   Keyvanfard M (Faculty of Sciences, Islamic Azad Univ, Majlesi Branch, Isfahan, Iran, Email: keyvan45638@yahoo.com) : Kinetic-catalytic-spectrophotometric determination of ultra trace amounts of rhodium(III) by its catalytic effect on the oxidation of SPADNS by metaperiodate in micellar media. Asian J Chem 2007, 19(6), 4777-84.

A new sensitive and simple kinetic spectrophotometric method was developed for the determination of ultra trace amounts of Rh(III). The method is based on the catalytic effect of Rh(III) on the oxidation of sodium 2-(p-sulfophenyl-azo)-l,8-dihydroxy-naphthalene-3,6-disulfonate (SPADNS) by metaperiodate at pH 7.5 in micellar media. The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of SPADNS at 517 nm with a fixed-time method. The decrease in the absorbance of SPADNS is proportional to the concentration of Rh(III) in concentration range 1.0-250.0 ng/mL, with a fixed time of 0.5-4.5 min from initiation of the reaction. The limit of detection is 0.77 ng/ mL Rh(III). The relative standard deviation of 0.020 and 0.040 μg/mL Rh(III) was 1.9 and 2.3%, respectively. The method was applied to the determination of rhodium in water sample and synthetic water sample.

5 illus, 3 tables, 15 ref

016236   Karthikeyan J;Parameshwara P;Nityananda Shetty A (Chemistry Dep, National Institute of Technology, Karnataka, Surathkal, Srinivasnagar-575 025, Email: nityashreya@rediffmail.com) : Indirect complexometric determination of mercury(II) using 3-acetyl-2-thiohydantoin as a selectiv masking agent. Indian J chem Technol 2008, 15(5), 493-6.

A complexometric method for the determination of mercury(II) in presence of other metal ions is described based on the selective masking action of 3-acetyl-2-thiohydantoin towards mercury(II). Mercury(II) present in a given sample solution is first complexcd with an excess of EDTA and the unreacted EDTA is titrated against standard lead nitrate solution at pH 5-6 (hexamine buffer) using xylenol orange as the indicator. A 0.5% solution of 3-acetyl-2-thiohydantoin is then added to displace EDTA from the Hg(II)-EDTA complex. The released EDTA is estimated. Reproducible and accurate results are obtained for 3.96 - 80 mg of mcrcury(II) with relative error less than ± 0.25% and coefficient of variation not more than 0.38%. The effects of various ions were studied. The method is used 'or the analysis of mercury in its synthetic mixtures of ions and in complexes.

3 tables, 31 ref

016235   Karimi M A;Nateghi M R;Malekzadeh M; Banifatemeh F;Moradlou O (Chemistry Dep, Islamic Azad Univ of Yazd, Yazd, Iran, Email: m_karimi@pnu.ac.ir) : Simultaneous spectrophotometric determination of paracetamol and p-aminophenol by H-point standard addition method and partial least squares regression. Asian J Chem 2007, 19(6), 4533-46.

The methods were based on the difference in the rate of reduction of iron(III) with PAR and PAP in the presence of 2,2'-bipyridine (Bpy) and subsequent complex formation between resulted Fe(II) and 2,2'-bipyridine. The coloured complex of [Fe(Bpy)₃]²⁺ resulted can be monitored at 520 nm. The results showed that the simultaneous determination of PAR and PAP could be performed in their concentration ranges of 0.4-70.0 and 0.03-8.0 <109>g mL^-1 for HPASM, 2.0-100.0 and 0.2-10.0 μg mL^-1 for PLS method, respectively. The total relative standard error for applying the PLS method on 10 synthetic samples in the concentration ranges of 4.0-28.0 μg mL^-1 of PAR and 0.5-6.0 μg mL^-1 of PAP was 3.79. The proposed methods were successfully applied to the simultaneous determination of PAR and PAP in several commercially available PAR formulations and satisfactory results were obtained.

3 illus, 7 tables, 30 ref

016234   Joseph J;Basheer K M;Radhakrishnan Nair T D (Chemistry Dep, Univ of Calicut, Calicut-673 635, Email: tdrnair@rediffmail.com) : Effect of substituents on the kinetics of the oxidation of benzyl chloride using acid-dichromate. Asian J Chem 2007, 19(6), 4733-8.

Kinetics of the oxidation of benzyl chloride and some of its para-substituted derivatives by acid-dichromate have been investigated in acetic acid-water mixture. The reaction shows first order dependence on the concentrations of the oxidant as well as the substrate. The reaction is acid catalyzed and shows fractional order with respect to sulphuric acid concentration. The product of oxidation is the corresponding benzaldehyde. Electron releasing substituents accelerate the reaction, whereas electron withdrawing groups retard the rate. The rate data obey the Hammett's relationship. The reaction constant ρ is negative. Isosbestic point was found at 297 nm. The reaction does not induce polymerization of acrylonitrile. The effect of solvent composition shows that the rate increases with an increase in the polarity of the solvent. Activation parameters have been evaluated and a mechanism consistent with the kinetic results has been proposed.

6 tables, 10 ref

016233   Jha G S;Chhabra P;Suri G;Tyagi M;Arora P; Seshadri G;Khandal R K (NO, Shriram Institute for Industrial Research, 19, University Road, Delhi-110 007, Email: rkhandal@shriraminstitute.org) : Designing sulfur containing bifunctional building block with improved refractiv index. E J Chem 2009, 6(2), 399-411.

Sulfur and chlorine containing bifunctional diols with C-S bond has been prepared starting from chloroepoxy alkane and thioaicohol. The studies of FTIR, TLC, HPLC and NMR have been used to understand the reaction mechanism, as well as for optimization of the reaction parameters. The reaction is highly exothermic and the effect of temperature, rate of addition of reagents and reaction time are important factors affecting the formation of diol. Viscosity studies, HPLC, FTIR, NMR and acid number studies have shown that, these parameters could be used as process control parameters for the synthesis of diol. Refractive index of the synthesized diol is found to be higher than that of the reactants used.

13 illus, 5 tables, 9 ref

016232   Jeena V R;Janardanan C (Chemistry and Research Dep, Sree Narayana College, Kannur-670 007, Email: snccan@md3.vsnl.net.in) : Lead selective zirconium(IV) sulphosalicylomolybdate as three component ion exchanger. Asian J Chem 2007, 19(6), 4251-7.

A three component inorganic ion exchanger zirconium(IV) sulphosalicylomolybdate has been prepared under varying conditions. Characterization of the exchanger was done by determining ion exchange capacity, distribution coefficient for various metal ions, chemical analysis, pH titration, IR Spectra and thermal analysis. The distribution coefficients (K_d) of 10 metal ions were determined. On the basis of difference in distribution coefficients, some analytically important binary (Cd²⁺V Pb²⁺, Zn²⁺/Pb²⁺, Ca²⁺/Pb²⁺, Th⁴⁺/Pb²⁺, Cd²⁺/Cu²⁺, Zn²⁺/Cu²⁺ and Th⁴⁺/Cu²⁺) and ternary (Th⁴⁺/Ni²⁺/Pb²⁺, Th⁴⁺/Co²⁺/Pb²⁺, Th⁴⁺/Cd²⁺/ Pb²⁺) separations of metal ions have been achieved. The significance of the exchanger is revealed by the important separations carried out from wastewater collected from spinning and weaving mills near Kannur.

2 illus, 4 tables, 26 ref

016231   Jaggi N;Jaiswal R M P (Physics Dep, College Univ, Kurukshetra Univ, Kurukshetra-136 119, Email: neena_jaggi@rediffmail.com) : Assignment of infrared and raman spectra of 1-chloroheptane. Asian Chem Lett 2006, 10(3-4), 133-41.

Infrared and Raman spectra of 1-chloroheptane liquid at ambient temperatures have been recorded and interpreted with the aid of normal coordinate calculations. 1-chloroheptane is shown to exhibit rotational isomerism. Five different conformations for the molecule have been identified. The conformation with symmetry C_s is expected to be the most stable to which most of the prominent bands could be assigned.

4 illus, 1 table, 15 ref

016230   Ishwar Bhat K;Maity S;Subrahmanyam E V S (Pharmaceutical Chemistry Dep, N G S M Institute of Pharmaceutical Sciences, Mangalore-575 005, Email: bhatishwar@yahoo.co.in) : Synthesis and antimicorbial studies of some azetidinone derivatives from 8-hydroxy quinoline. Asian J Chem 2007, 19(6), 4363-7.

A new series of azetidinone derivatives have been synthesized. Structures of these azetidinone derivatives have been confirmed by analytical and spectral data. The compounds have also been screened for antibacterial and antifungal activity.

3 tables, 12 ref

016229   Hasaninejad A;Zare A;Jafari F;Moosavi-Zare A R (Chemistry Dep, Faculty of Sciences, Persian Gulf Univ, Bushehr-751 169, Iran, Email: ahassaninejad@yahoo.com) : P₂O₅/SiO₂ as an efficient, green and heterogeneous catalytic system for the solvent-free synthesis of 3,4-dihydropyrimidin-2-(1H)-ones (and -thiones). E J Chem 2009, 6(2), 459-65.

A simple, green and efficient solventless procedure for the synthesis of 3,4-dihydropyrimidin-2-(1H)-ones (and -thiones) from aldehydes, β-ketoesters and urea or thiourea in the presence of catalytic amount of silica-supported P₂O₅ (P₂O₅/SiO₂) at 85 °C is described. Using this method, the title compounds were produced in high yields.

3 tables, 47 ref

016228   Harikumaran Nair M L;Mariamma A T (Chemistry Dep, Univ College, Thiruvananthapuram-695 034, Email: drmlhnair@gmail.com ) : Synthesis and spectral analysis of some Ru(III) complexes of azodyes derived from 1-phenyl-2,3-dimethyl-4-amino pyrazol-5-one. Asian J Chem 2007, 19(6), 4653-60.

Eight novel complexes of the azodyes 2,3-dimethyl-1 -phenyl-4-(2-hydroxy-5-methyl phenyl azo)-pyrazol-5-one (cresol azo antipyrine CAAP) and 2,3-dimethyl-1-phenyl-4-(2,4-dihydroxyphenylazo) pyrazol-5-one (resorcinol azo antipyrine RAAP) have been synthesised and characterized by elemental analysis, IR, electronic, ESR and NMR spectra, magnetic, conductance measurements and cyclic voltammetric studies. The ligands are found to behave in a neutral bidentate manner. All the complexes are non electrolytes with octahedral geometry having general formulae [RuCl₂X(PPh₃) (CAAP)] and [RuCl₂X(PPh₃) (RAAP)] where X = Cl, NCS, NO₃ or ClO₄. The X-ray powder diffraction patterns of one of the complexes has also been examined and found to be orthorhombic with unit cell dimensions a=16.0189 Angstrum, b=11.4826 Angstrum and c = 7.6652 Angstrum. The electrochemical behaviour of one of the complexes is followed using cyclic voltammetry.

1 illus, 2 tables, 41 ref

016227   Harikumaran Nair M L;Kumari Nisha K R (Chemistry Dep, Univ College, Thiruvananthapuram-695 034, Email: drmlhnair@gmail.com) : Some novel oxomolybdenum(V) and dioxomolybdenum (VI) complexes of thiophene-2-aldehyde-N(4)-phenylthiosemicarbazone. Asian J Chem 2007, 19(6), 4689-96.

Some novel oxomolybdenum(V) complexes of general formula [MoO(TAPT)XCl₂] and dioxomolybdenum(VI) complexes of general formula [MoO₂(TAPT)XCl] (X = Cl, NO₃, NCS or ClO₄ and TAPT = thiophene-2-aldehyde-N(4)-phenyl thiosemicarbazone) have been synthesized and characterized by elemental analysis, magnetic moment and conductance measurements, IR, ESR, electronic and NMR spectral studies. The thermal behaviour of one of the complexes has also been examined. The ligand and its few metal complexes were screened for their antibacterial activities against gram positive and gram negative bacteria and also screened for their antifungal activity. The molar conductance values of the complexes indicate that the complexes are non electrolytes. The X-band ESR spectra indicate that the pentavalent Mo in the complex [MoO(TAPT)NCS C1₂] is monomeric in nature. The X-ray diffraction patterns of the complex [MoO₂(TAPT) NO₃Cl] has been examined and found to be orthorhombic with unit cell dimensions such as a= 10.89 Angstrum, b = 8.12 Angstrum and c = 7.03 Angstrum.

3 illus, 2 tables, 29 ref

016226   Harikumaran Nair M L;Kumari Nisha K R (Chemistry Dep, Univ College, Thiruvananthapuram-695 034, Email: drmlhnair@gmail.com) : Synthesis, spectral and antimicrobial studies of some oxomolybdenum(V) and dioxomolybdenum(VI) complexes of schiff base derived from 1-phenyl-2,3-dimethyl-4-amino-5-pyrazolone. Asian J Chem 2007, 19(6), 4487-94.

Some novel oxomolybdenum(V) complexes of general formula [MoO(TAAP)XCl₂] and dioxomolybdenum(VI) complexes of general formula [MoO₂(TAAP)XCl] (X = Cl, NO₃) NCS or ClO₄ and TAAP-1-phenyl-2,3,-dimethyl-4-(N-thienylidene)-5-pyrazolone) have been synthesized and characterized by elemental analysis, IR, UV, ESR and NMR spectral studies. The thermal behaviour of the complex [MoO₂(TAAP)NCSCl] has also been examined. The ligand and its few metal complexes were screened for their antibacterial activities against gram positive and gram negative bacteria and also screened for their antifungal activities. The molar conductance values of the complexes indicate that the complexes are non-electrolytes. The X-ray powder diffraction pattern of the complex [MoO₂(TAAP)(NCS)Cl] has been examined and found to be orthorhombic with the unit cell dimensions such as a = 24.35 Angstrum, b = 10.89 Angstrum and c = 9.94 Angstrum. The X-band ESR spectra indicate that the pentavalent Mo in the complexes [MoO(TAAP)Cl₃], [MoO(TAAP)NCSCl₂] and [MoO(TAAP)ClO₄Cl₂] is monomeric in nature.

2 illus, 3 tables, 19 ref

016225   Hamzehlooian M;Yeganegi S (Petrochemical Processes Dep, Islamic Azad Univ, Joybar, P O Box 47715-195, Iran, Email: m.hamzehlooian@gmail.com) : Structural and NBO studies of anomeric effect in polyoxa, polyaza and polycyclics compounds. Asian J Chem 2007, 19(6), 4395-4406.

The geometries of four 3hetrocyclic (polyaza polyoxa poly-cyclic) compounds have been completely optimized at BS1yp/ 6-31G** and HF/6-31G* ab initio quantum mechanical levels and compared with the X-ray structural data. Natural bond orbital (NBO) analysis has carried out quantitatively to estimate delocalization in O-C-N units. The optimized geometrical parameters agree with the acceptor-donor interaction scheme of NBO analysis. The results show that the structures of considered compounds affected by the anomeric effect.

4 illus, 8 tables, 12 ref

016224   Haghgooie H;Tabrizi L;Nouri S (Chemistry Dep, College of Science, Urmia Univ, Urmia-57135-165, Iran, Email: sirousno@yahoo.com.au) : Synthesis and characterization of some complexes of Cr(II) with 3-cyano-2(1H)-pyridone derivatives as ligands. Asian J Chem 2007, 19(6), 4463-72.

By reaction of acetates of Cr(II) [Cr₂(O₂CCH₃)₄2H₂O] with the sodium salt of 3-cyano-2(1H)-pyridone derivatives, the dimeric compounds of Cr₂(L)₄-H₂O, (L = 3-cyano-6-methyl-; 3-cyano-4,6-dimethyl-; 3-cyano-5,6-dimethyl-; 3-cyano-6-isopropyl-; 3-cyano-6-phenyl-2(1H)-pyridone) have been synthesized. These complexes have been characterized by elemental analysis, FTIR, ¹H NMR, UV-Vis spectra and atomic absorption spectrometer and have been ascertained that the nitrogen atom of the cyano group remain without coordinated. In all complexes, anion 3-cyano-2(1H)-pyridone derivatives act as 1,3-bridging ligands. The stability of all five complexes is remarkably high. These complexes appear to be stable toward dry air at 25°C indefinitely, but exposure to moisture-saturated air causes a slight greenish ting to appear after ca. 10 d.

1 illus, 7 tables, 12 ref

016223   Gupta K R;Wankhede S B;Tajne M R;Wadodkar S G (Pharmaceutical Sciences Dep, S K B College of Pharmacy, Near Dragon Palace Temple, Behind Railway Station, New Kamptee, Nagpur-441 002, Email: krishnargupta@rediffmail.com) : High performance thin layer chromatographic estimation of atenolol and indapamide from pharmaceutical dosage form. Asian J Chem 2007, 19(6), 4183-7.

Atenolol and indapamide in combination is available as tablet dosage forms in the ratio of 20:1. HPTLC method was developed for analysis of above formulation. Atenolol and indapamide were seperated on the plate coated with silica gel 60G F₂₅₄ using a mixture of toluene:ethanol:acetone:acetic acid (7:2.5:3:0.3 v/v) as mobile phase. Quantification was carried out by the use of densitometer in absorbance mode at 266 nm. The R_f value of atenolol and indapamide was found to be 0.21 and 0.74, respectively. The per cent recovery was found to be 99.42/100.51 and 99.07/98.65% for atenolol and indapamide by height by area, respectively. The proposed method was quantitatively evaluated in terms of calibration of concentration range, stability and accuracy. It can be adopted for routine analysis of the formulation.

1 illus, 3 15 ref

016222   Gupta K R;Wankhede S B;Tajne M R;Wadodkar S G (Pharmaceutical Sciences Dep, S K B College of Pharmacy, Near Dragon Palace Temple, Behind Railway Station, New Kamptee, Nagpur-441 002, Email: krishnargupta@rediffmail.com) : Simultaneous determination of amlodipine and ramipril by high performance thin layer chromatography. Asian J Chem 2007, 19(6), 4177-82.

A simple, selective and validated high performance thin layer chromatographic method has been developed for the simultaneous estimation of amlodipine and ramipril in tablets. Aluminium plates precoated with silica gel G 60 F₂54 was used as stationary phase and toluene:ethanol:acetone: ammonia in the ratio of (7:2:1:0.3 v/v) was used as mobile phase. Quantification was carried out by the use of densito-metric absorbance mode at 217 nm. The content of amlodipine and ramipril in tablet/capsule formulation was calculated and found to be 98.66/99.25, 100.17/99.36, 99.93/100.39 and 99.96/100.06% by height and area for tablet and capsule, respectively. The proposed HPTLC method was quantitatively evaluated in terms of stability, precision, repeatability, accuracy and calibration correlation proving its utility in routine analysis of its tablet dosage form.

1 illus, 3 tables, 14 ref

016221   Guangmei C;Ye C;Yiping H (Chemistry Dep, Anhui Institute of Architecture and Industry Hefei, 230601 Anhui Province, P.R. China, Email: chen_gm168@yahoo.com.cn) : Crystallization behaviour of polypropylene containing nano-calcium carbonate and organic nucleating agents. Asian J Chem 2007, 19(6), 4763-76.

The crystallization behaviour of polypropylene (PP) and PP with additives was investigated by DSC. It was found that the crystallization temperatures and the crystallization rates of PP increased with the addition of nanometer-scale calcium carbonate (nm CaCO₃) and with the increasing amount of the organic nucleating agents 1,3; 2,4-di-p-chlorobenzylidene sorbitol (CDBS). The crystallization temperature for the PP with CDBS was higher than for non-nucleated PP by 20-25 K when the samples were cooled from molten. The values of Avrami exponent 'n' indicated the addition of nm CaCO₃ and CDBS could affect the nucleation process and the crystalline morphology. Three methods are used to deal with the non-isothermal crystallization process for PP and nucleated PP. Ozawa equation could not describe satisfactorily the non-isothermal crystallization behaviour of PP with CDBS in this study, while Mo's method could. The results obtained by modified Avrami equation indicate that the primary crystallization stage for non-isothermal melt crystallization might correspond to a three-dimensional spherical growth with thermal nucleation. The non-isothermal crystallization kinetic parameters revealed that the addition of nm CaCO₃ and CDBS increases the crystallization rate of PP from the molten state obviously. The results of DSC and the polarized light microscopy display CDBS is an effective nucleating agent for PP. But more CDBS in samples may affect the crystalline morphology of PP.

7 illus, 4 tables, 20 ref

016220   Gouranlou F;Kohsar I (Material Science Dep, Malekashtar Univ, Lavizan, Tehran, Iran, Email: faridehgouranlou@gmail.com ) : Characterization and calculation of detonation parameters of 2,6-diamino-3,5-dinitropyrazine-1-oxide by BKW codes. Asian J Chem 2007, 19(6), 4309-14.

2,6-Diamino-3,5-dinitropyrazine-l-oxide (LLM-105) is a new molecules which shows performance and insensitivity between those of HMX and TATB. Its calculated energy content is about 85% that of HMX and 15% more than that of TATB. It is thermally stable, insensitive to shock, spark and friction and has impact insensitivity level approaching that of TATB. These combined properties make it a realistic high performance IHE material; attractive for applications that require moderate performance and insensitivity. In this article, the detonation parameters by BKW codes has been calculated and compared with the results of BKW for TATB, TNT, LLM-105, HMX.

4 tables, 13 ref

016219   Gohari R J;Gorouh K A (Chemistry Dep, Islamic Azad Univ, Bardsir Branch, Bardsir, Iran, Email: rasool_jamshidi_gohari@yahoo.com) : Modified bentonite as sorbent for removal of Tl+ and Bi3+ from water samples. Asian J Chem 2007, 19(6), 4837-40.

Modified bentonite sorbent is used for removal of TI⁺ and Bi³⁺ from water samples at trace levels. Modification of bentonite was established with Pd²⁺ and TiO₂ in the solution and solid state. The results showed that TiO₂ is proved to be better modifier.

1 illus, 8 ref

016218   Galai H;Nahdi K;Trabelsi Ayadi M (LACReSNE, Faculte des Sciences de Bizerte, 7021 Zarzouna Bizerte, Tunisia, Email: hgalai@yahoo.fr) : Isothermal behaviour of natural Tunisian dolomite under controlled pressure of carbon dioxide. Asian J Chem 2007, 19(6), 4231-44 .

The first half decomposition of natural Tunisian dolomite sample, was investigated by thermogravimetric measurements and in situ X-Ray diffraction, in controlled CO₂ pressure (20 > Pco₂< 500 h Pa) and in isothermal conditions (in the temperature range 823-1023 K). The thermograms exhibited two consecutive weight losses, corresponding to fractional conversion ranges of 0-0.2 and 0.2-1: A decelerating effect of was observed only during the second weight loss. In situ X-ray diffraction results indicate that crystal lattice of dolomite undergoes, during the thermal treatment, a dilatation along the c direction, then it decomposes progressively into poor crystalline MgO and a magnesian calcite Mg_0.052Ca_0.948 CO₃. The characterization of the final product using SEM and XPS has shown that MgO could precipitate at the surface of CaCO₃.

12 illus, 1 table, 20 ref

016217   Foroumadi A;Firoozpour L;Nematollahi N; Ebrahimabadi A H;Emami S;Moshafi M H;Asadipour A;Shafiee A (Pharmaceutical Sciences Research Center, Medical Sciences Univ of Tehran, Tehran, Iran, Email: aforoumadi@yahoo.com) : Synthesis of new fluoroquinolones containing a N-[5-(fluorobenzylthio)-1,3,4-thiadiazol-2-yl]piperazine moiety. Asian J Chem 2007, 19(6), 4547-52.

A series of N-[5-(fluorobenzylthio)-1,3,4-thiadiazol-2-yl]-piperazinylquinolones derivatives (4a-i) have been synthesized as potential antibacterial agents. The 2-amino-5-(fluorobenzylthio)-1,3,4-thiadiazole derivatives (6a-c) were obtained from 5-amino-1,3,4-thiadiazol-2-thiol (5). The treatment of compound 5 with fluorobenzyl chloride derivatives afforded S-benzyl intermediates 6a-c. Diazotiza-tion of amine 6a-c with NaNO₂ in hydrochloric acid in the presence of copper powder gave the corresponding 2-chloro-5-(fluorobenzylthio)-1,3,4-thiadiazoles (7a-c). Reaction of compounds 7a-c with piperazinyl quinolones (1-3) in DMF in the presence of NaHCO₃ gave the target compounds 4a-i. The structure of synthesized compounds was confirmed by elemental analysis, IR and ¹H NMR spectra.

18 ref

016216   Filmwala Z A;Nandavadekar S M;Patil R M (Nadkarny Sacasa Research Laboratory, Chemistry Dep, St. Xavier's College, Mumbai-400 001, Email: sanjaynandavadekar2000@yahoo.com) : Synthesis, spectral studies and antimicrobial activity of Schiff bases derived from 4,4'-diaminodibenzyl with substituted salicylaldehydes and metal complexes with Mn(II), VO(II) and UO₂(II). Asian J Chem 2007, 19(6), 4697-703.

A series of polydentate Schiff bases have been prepared by the condensation of 4-4'- diaminodibenzyl with different aldehydes such as salicylaldehyde and substituted salicylaldehydes. The Schiff bases characterized by elemental analysis and spectral methods. The metal complexes of Mn(II), VO(II) and UO₂(II) have been prepared by the reaction of Schiff bases. The analytical and spectral data support the octahedral structure for Mn(II) and UO₂(II) and square pyramidal for VO(II) complexes. The antimicrobial activities of Schiff bases and their metal complexes have been studied by screening the compounds against micro organisms such as E. coli, S. typhi, B. subtills and S, aureus.

2 illus, 2 tables, 21 ref

016215   Fathi M R;Pourreza N;Abbaszadeh S (Chemistry Dep, Shahid Chamran Univ, Ahvaz, Iran, Email: fathiemadabadi@yahoo.com) : Kinetic method for spectrophotometric determination of iron(III) by its catalytic effect on the reduction reaction of methyl red with potassium pyrosulfite. Asian J Chem 2007, 19(6), 4739-44.

A kinetic spectrophotometric method for the determination of iron(III) is described. The method is based on the catalytic effect of iron(III) on the reduction reaction of methyl red by pyrosulfite. The reaction is followed spectrophoto-metrically by measuring the change in absorbance at 522 nm using a fixed time method (2.5 min). The effect of different parameters on the reaction was studied to obtain optimum conditions. The calibration curve was linear in the range of 0.4-2.0 μg mL^-1 of iron(III) and the 3S_b detection limit was 0.07 μg mL^-1. The method was successfully applied to the determination of iron(III) in an iron oral drop and clover plant.

4 illus, 3 tables, 15 ref

016214   El Ajaily M M;Morad F M (Chemistry Dep, Faculty of Science, Garyounis Univ, Benghazi, Libya, Email: melagaily@yahoo.com) : Cobalt(II) and copper(II) schiff base complexes. Asian J Chem 2007, 19(6), 4379-84.

Co(II) and Cu(II) Schiff base complexes derived from salicylaldehyde and anthranilic acid (L) have been prepared and characterized by using elemental analysis, thermogravi-metric analysis, magnetic analysis, infrared and electronic spectra. The theoretical elemental analysis data of the prepared Schiff base and its complexes are in a good agreement with those found data and show the formation of 1:1 [M:L] ratio. Thermogravimetric analysis reveals the presence of hydrated and coordinated water molecules. The magnetic moment values show the existence of three unpaired electrons for Co(II) complex and one unpaired electron for Cu(II) complex. The infrared spectral data display the coordination sites of the Schiff base towards the Co(II) and Cu(II) ions. The electronic absorption spectra exhibit π→π* (phenyl ring) and n→π* (HC=N) transitions and the expected geometrical structures of the prepared complexes.

1 table, 11 ref

016213   Edison B (NO, , MNR Technology Pte Ltd, (Speciality Chemicals Manufacturers), Singapore, Email: edisonb79@gmail.com) : Analysis of tocopherols by high performance liquid chromatography. E J Chem 2009, 6(2), 395-8.

Gas chromatography is the key technique for organic components and also for tocopherols analysis. High performance liquid chromatography has an important role to take part in applications such as the handling of less usual samples, prevention of degradation of heat sensitive functional groups and for micro preparative purposes. Many approaches for development of improved methods are suggested, especially for reversed phase applications.

1 illus, 9 ref

016212   Dodkey-Supekar A;Natarajan G S (NO, S.B. Education Society's Science College, Aurangabad-431 001) : Synthesis and conductance behaviour of lanthanides(III) complexes of 1,10-phenanthroline and 2,2'-bipyridyl. Asian J Chem 2007, 19(6), 4914-16.

The synthesis and conductance behaviour of some lanthanide(III) complexes with nitrogen containing ligands such as 1,10-phenanthroIine and 2,2'-bipyridyl have been carried out. These complexes showed the values of the equivalent conductances between 80-100 mhos cm^-1 with suggested that the complex behaves as a 1:3 electrolyte.

^ssc2 tables, 3 ref

016211   Delattre C;Michaud P;Courtois J;Vijayalakshmi M A (Centre for BioSeparation Technology, Vellore Institute of Technology-University, Vellore-632 014, Email: cedric_delattre@hotmail.com ) : Specific interactions between glucuronic acid and amino acids at the interface using pseudo bioaffinity chromatography and NMR studies. Curr Sci 2008, 94(10), 1279-84.

A new approach to protein-oligosaccharide interaction studies was envisaged using pseudo bioaffinity chro-matography with L-histidine amino acid immobilized onto poly(ethylene-vinyl alcohol) hollow-fibre membranes. These interactions have also been investigated by NMR spectroscopy to quantify ionic binding during the interaction between the oligosaccharides and the amino acid. Oligouronides such as tricellouronic oligosaccharides obtained by enzymatic depolymeriza-tion of a bacterial poly β-(1,4)-glucuronic acid, were chosen and applied with different derivates to investigate the specific effects for molecular association.

4 illus, 1 table, 23 ref

016210   Choudhari J R;Berad B N (Chemistry Dep, Shri Shivaji Science, College, Amravati-444 603) : Synthesis and structural studies of 2-phenylimino-3-aroyl/acyl-5-aroyl/acyl hydrazino-1,3,4-thiadiazolidines and their acetyl derivatives. Asian J Chem 2007, 19(6), 4502-6.

Synthesis of several 2-phenylimino-3-aroyl/acyl-5-aroyl/ acyl hydrazino-1,3-4-thiadiazolidines (V) have been carried out by the interaction of bis-1,5-aroyl/acyl-3-thiocarbohy-drazides (II) with N-phenylisocyanodichloride (III). The product obtained (IV) on basification with dilute ammonium hydroxide afforded the free bases (V). The title compounds in 1:1 ratio gave monoacetyl derivatives (VI). The structures of all these compounds were established on the basis of elemental analysis and spectral studies.

1 table, 22 ref

016209   Chamani J (Biology Dep, Faculty of Science, Islamic Azad Univ, Mashhad Branch, Mashhad, Iran, Email: chamani@ibb.ut.ac.ir) : Conformation and stability of the alpha-helical intermediate of intact and thiol-modified beta-lactoglobulin induced by sodium dodecyl sulfate. Asian J Chem 2007, 19(6), 4203-13.

β-Lactoglobulin is a predominantly (3-sheet protein, although it has a markedly high intrinsic preference for α-helical structure. β-Lactoglobulin assumes a monomeric native conformation at acidic condition. It has a free thiol at Cys 121, which is buried between the β-barrel and the C-terminal major α-helix. This thiol group was specifically reacted with 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB) at pH 2, producing a modified β-lactoglobulin (TNB-β-LG) containing a mixed disulfide bond with 5-thio-2-nitrobenzoic acid. The formation of non-native α-helical intermediate of intact and thiol modified β-lactoglobulin was induced by sodium dodecyl sulfate. The conformation and stability of non-native α-helical intermediate (αI) state of TNB-β-LG were studied by circular dichroism and fluorescence techniques. The effect of sodium dodecyl sulfate on the structure of αI state at acidic condition was utilized to investigate the contribution by hydrophobic interactions to the stability of αI intermediate. The present results suggest that modification of the buried thiol group destabilizes the rigid hydrophobic core, producing a monomeric state that is native-like at pH 2. Therefore TNB-P-LG will become a useful model to analyze the conformation and stability of the intermediate of protein folding.

4 illus, 39 ref

016208   Chakra Varthy Akula K;Kanumalla D (NO, Dr Reddy's Laboratories Limited, D 7-I-27, III Floor, Ameerpet, Hyderabad-500 017, Email: kalyan@drreddys.com) : Microwave synthesis of n-methyl-3-N'-(1-trizolyl)-deriv 4-substituted pyrroles. Asian J Chem 2007, 19(6), 4277-80.

A microwave-enhanced synthesis of N-methyl-3-N'-(1-trizolyl)-4-substituted pyrroles, under solvent free conditions is described. The yields and especially the reaction time are noticeably improved in comparison with conventional heating.

2 tables, 12 ref

016207   Byrappa K;Suresh Kumar B V (Studies in Geology Dep, Mysore Univ, Manasagangotri-570 006, Email: bvsureshkumar@yahoo.com) : Characterization of zeolites by infrared spectroscopy. Asian J Chem 2007, 19(6), 4933-5.

Various infrared bands assigned to microporous molecular sieve zeolites is described.

^ssc1 table, 5 ref

016206   Boukhalfa C;Mennour A;Reinert L;Dary M; Duclaux L (Laboratory of Pollution and Water Treatment, Chemistry Dep, Univ of Mentouri, Constantine, Algeria, Email: chahrazed_boukhalfa@yahoo.com) : Removal of copper from aqueous solutions by coprecipitation with hydrated iron oxide. Asian J Chem 2007, 19(6), 4267-76.

The coprecipitation of Cu(II) ions with hydrated iron oxide in aqueous solution was studied using batch experiments by varying pH, iron and copper concentrations and [Cu(II)]/ [Fe(III)] molar ratio and also in the presence of competing ions. Analytical methods for solids analysis were performed to characterize the interaction of copper with the surface of the hydrous oxide. The uptake of Cu(II) showed typical cat-ionic-type behaviour. The effect of the molar ratio was shown to depend on the copper concentration at high concentrations anomalous behaviour was observed. In the presence of Pb(II) and Zn(II), the Cu(II) removal was slightly decreased, whereas, it was enhanced in the presence of SO₄^2-.

9 illus, 21 ref

016205   Borhade A V;Wakchaure S G (Chemistry Dep, S V M Engineering College, Chincholi-413 569, Email: sanjaywakchaure9@yahoo.co.in) : Synthesis, infrared and powder X-ray diffraction studies of mixed halogen sodalites of the type Na₈[AlSiO₄]₆Cl_2-xI_x and Na_8-xAg_x [AlSiO₄]6C_l0.52I_1.48. Asian J Chem 2007, 19(6), 4420-8.

The structure of mixed halogen sodalite was established by X-ray Rietvelt refinement in the space group P43n. While, a silver containing derivatives, Na_8-xAg_x[AlSiO₄]₆ Cl_0.52I_1.48, obtained through aqueous ion exchange method. In the study more emphasis is given to find out the correlation of Si-O-Al angle and unit cell parameter with concentration of iodide for different sodalites of Na₈[AlSiO₄]₆,Cl_2-xI_x (where, 0 < x < 2).

6 illus, 4 tables, 27 ref

016204   Barot T G;Patel P K (Chemistry Dep, M.G.Science Institute, Ahmedabad Gujarat, Email: drtushar8055@gmail.com) : RP-HPLC method for the estimation of donepezil hydrochloride dosage form. E J Chem 2009, 6(2), 594-600.

A simple and accurate methods to determine donepezil, in tablet dosage form, were developed and validated using liquid chromatograplw (LC). The LC separation was achieved on a Inertsil C8-3, 25 cm x 4.6-mm, 5 μ in the isocratic mode using buffer : methanol: triethylamine (550:450:5)v/v, adjusted to pH 2.50±0.05 with orthophosphoric acid, as the mobile phase at a flow rate of 1.0 mL/min. The methods were performed at 271 nm. In LC method, quantification was achieved with PDA detection over the concentration range of 20-60 μg/mL with mean recovery of 100.18±0.75%. The method was validated by determining its sensitivity, accuracy and precision. The proposed method is simple, fast, accurate and precise and hence can be applied for routine quality control of donepezil HC1 in bulk and tablet dosage form.

5 tables, 15 ref

016203   Barnwal R P;Chary K V R (Chemical Sciences Dep, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai-400 005, Email: chary@tifr.res.in) : Efficient method for secondary structure determination in polypeptides by NMR. Curr Sci 2008, 94(10), 1302-6.

Recent advancements in NMR are having a significant impact in structural biology. During the last two decades, NMR has become a powerful tool in the 3D structure determination of proteins. A prelude to such structure determination is the sequence-specific resonance assignments and characterization of various short ordered stretches, which are called secondary structural elements. Pro-poses an alternative and efficient method for the determination of secondary structures in proteins. We strongly believe that ΔC'-ΔC^β (the difference in the deviations between the observed and random coil chemical shift values of C' and C^β spins) provides accurate signatures of various secondary structural elements present in any given protein, whether it is predominantly α-helical or β-sheet in its content.

3 illus, 1 table, 21 refr

016202   Baghel H K;Singh L R (Chemistry Dep, B S A College, Mathura-281 004) : Adsorption of di-butylester of sodiumsulpho succinic acid at the hydrocarbon mixture-water interfaces. Asian J Chem 2007, 19(6), 4495-4501.

A modified drop volume technique was used for measuring interfacial tension (γ) at mixture containing entire mole fraction range of benzene in benzene and toluene-water interfaces with varying concentration of di-butylester of sodiumsulpho succinic acid (BSS) at 27°C using AGLA micrometer syringe (Burroughs Wellcome). It has been observed that there was regular decrease in interfacial tension with increase in concentration of BSS. From the data of interfacial tension at various concentration of surfactant, γ-log C curves were plotted. The values of surface excess, FS, have been calculated from the gradients of γ-log C curves using appropriate form of Gibb's adsorption equation. From these data, number of surfactant ions adsorbed per cm² of interface and the area occupied per surfactant ion have been estimated. The area corresponding to closest packing of mono-molecular film was determined by extrapolation of π-A curves back to zero surface pressure. It has been observed that as the mole fraction of benzene in mixture of benzene and toluene increases, the value of interfacial tension decreases and area corresponding to closest packing of mono-molecular film of BSS increases.

2 illus, 1 table, 9 ref

016201   Badri R;Shushizadeh M R (Chemistry Dep, College of Science, Chamran Univ, 61357-4-3169 Ahvaz, Iran, Email: rashidbadri@yahoo.com) : Silica sulfuric acid as an efficient reagent for bamberger rearrangement of phenyl hydroxylamine derivatives in solvent-free conditions. Asian J Chem 2007, 19(6), 4661-4.

Phenyl hydroxylamines undergo Bamberger rearrangement in the presence of silica sulfuric acid under solvent-free conditions to afford the corresponding 4-amino phenol derivatives in high yields.

1 table, 13 ref

016200   Ashok D;Arvind K (Chemistry Dep, Osmania Univ, Hyderabad-500 007, Email: ashokdou@gmail.com) : Microwave assisted synthesis of new 1-{2, 4-dihydroxy-5-[5-(aryl)-1-pyridine/pyrimidine-4-carbonyl)-4, 5-dihydro-1H-pyrazol-3-yl]-phenyl}-3-(aryl)-propenones and their antibacterial activity. E J Chem 2009, 6(2), 323-31.

A series of 1-{2, 4-dihydroxy-5-[5-(aryl)-l-pyridine/pyrimidine-4 carbonyl)-4, 5-dihydro-1 H-pyrazol-3-yl]-phenyl}-3-(aryl)-propenones (2a-h) have been synthesized from l-[2,4-dihydroxy-5-(aryl acryloyl)phenyl]-aryl propenones(1a-h) by Micheal addition with isoniazide/pyrazinic acid hydrazide under microwave irradiation and classical heating. The synthesized compounds were characterized by IR, ¹H-NMR, ¹³C-NMR and Mass spectral data. All the compounds were screened for their Antibacterial activity.

2 illus, 2 tables, 30 ref

016199   Anantha Kumar D;Sujan D P;Vijayasree V; Seshagiri Rao J V L N (A.U. College of Pharmaceutical Sciences, Andhra Univ, Visakhapatnam-530 003, Email: jvlns@yahoo.com) : Simultaneous determination of simvastatin and ezetimibe in tablets by HPLC. E J Chem 2009, 6(2), 541-4.

A reverse phase high performance liquid chromatographic method was developed for the simultaneous determination of simvastatin and ezetimibe in tablet dosage forms. The separation was effected on a C18 Supelcosil column (250 mm x 4.6 mm; 5μ) using a mobile phase consisting of 0.01 M ammonium acetate buffer and acetonitrile (35:65 v/v) at a flow rate of 1 mL/min. The detection was made at 240 nm. The retention times for ezetimibe and simvastatin were 5.9 and 8.5 min respectively. Calibration curves were linear over the ranges of 0.5-40 μg/mL for simvastatin and 2.5-50 μg/mL for ezetimibe. The proposed method was validated as per the ICH and USP guidelines. The method is accurate and precise and found to be suitable for the quantitative analysis of both the drugs individually and in combination in tablet dosage forms.

1 illus, 4 tables, 12 ref

016198   Amini M;Foroumadi A;Vosooghi M;Vahdatizadeh H R;Shafiee A (Medicinal Chemistry Dep, School of Pharmacy, Medical Sciences, Univ of Tehran, Tehran, Iran, Email: moamini@tums.ac.ir) : Synthesis and characterization of 2-alkyl-1-[4-(5-carboxy-1,2,3-thiadiazole-4-yl) benzyl]-4-chloro-1H-imidazole-5-carboxaldehydes. Asian J Chem 2007, 19(6), 4679-83.

Starting from ethyl 4-(4-methylphenyl)-1,2>3-thiadiazole-5-carboxylate (8), 2-alkyl-1-[4-(5-carboxy-1,2,3-thidiazole-4-y])benzyl]-4-chIoro-lH-imid azole-5-carboxaldeydes (4a,4b) were prepared.

9 ref

016197   Alzaydien A S (Chemistry Dep, Mutah Univ, P.O.Box 7, Jordan, Email: atef_sal99@yahoo.com) : Kinetics of alpha-amino acids acylation by p-nitrophenyl p-nitrobenzoate in water-propan-2-ol mixtures. Asian J Chem 2007, 19(6), 4214-24.

Kinetic studies of β-amino acids acylation by p-nitrophenyl p-nitrobenzoate in water-propan-2-ol mixtures were carried out at different temperatures under pseudo-first conditions by keeping the concentration of α-amino acid in thirty fold excess over that of the p-nitrophenyl p-nitrobenzoate. It can put the investigated α-amino acids in the following order according to their reacting ability in the acylation reaction : are L-proline>>glycine>L-<97>-alanine>L-valine>L-serine<62>DL-threonine. Increase of the water content in the binary water-propan-2-ol solvent leads to a decrease of energy, enthalpy and entropy of activation. The positive effect of water with its high dielectric constant on the rate of α-amino acids acylation was discussed.

5 illus, 7 table, 18 ref

016196   Alex P M;Aravindakshan K K (Chemistry Dep, Marthoma College, Chungathara, Nilambur, Kerala-679 334) : Synthesis, characterization and thermal decomposition studies of Cr(III), Mn(II) and Fe(III) complexes of N, N'-Bis[1,3-benzodioxol-5-ylmethylene]butane-1,4-diamine. E J Chem 2009, 6(2), 449-58.

A bidentate Schiff base ligand namely, N,N'-bis-1,3-benzodioxol-5-ylmethylene]butane-1,4-diamine was synthesised by condensing piperonal (3,4-dioxymethylenebenzaldehyde) with butane-1,4-diamine. Cr(III), Mn(II), Fe(III) complexes of this chelating ligand were synthesised using acetates, chlorides, bromides, nitrates and perchlorates of these metals. The ligand and the complexes were characterised by elemental analysis, ^-1H NMR, UV-Vis and IR spectra, conductance and magnetic susceptibility measurements and thermogravimetric analysis. The thermograms of three complexes were analysed and the kinetic parameters for the different stages of decompositions were determined.

6 illus, 5 tables, 42 ref

016195   Alemi A;Khandar A;Koshky F E (Inorganic Chemistry Dep, Faculty of Chemistry, Univ of Tabriz, Tabriz, Iran, Email: aa_alemi@yahoo.com) : Synthesis and characterization of antimony oxide doped cobalt oxide by rheological phase method. Asian J Chem 2007, 19(6), 4831-6.

Antimony doped cobalt oxid nanoparticles with composition Sb_xCo_3-xO₄ (0 ≤ x ≤ 0.024) were synthesized by rheological phase reaction and pyrolysis method. The products were characterized by X-ray powder diffraction, fourier transform infrared spectrum, scanning electron microscope, thermogravimetric analysis and simultaneous differential thermal analysis. Calcination of the precursor at 500°C resulted in the formation of antimony doped cobalt oxide nanoparticles of 45 nm in crystal size. Effect of calcination temperature on antimony doped Co₃O₄ crystal size was discussed.

5 illus, 11 ref