007089   Khanam A;Khan F (Electrochemical Laboratory, Chemistry Dep, Dr. H. S. Gour Univ, Sagar-470 003, Email: faridkhan58@yahoo.com) : Polarographic study of ternary complexes of [Cd<. J Indian Chem Soc 2008, 85(1), 89-91.

Interaction between Cd^II with some L-amino acids such as L-lysine, L-ornithine, L-threonine, L-serine, L-phenylglycine, L-phenylalanine, L-glutamic acid and L-aspartic acid as primary ligands and vitamin-PP (nicotinamide or niacinamide) as secondary ligand has been studied by simple DC polarography using dropping mercury electrode as an indicator electrode and calomel electrode (saturated) as reference electrode at pH = 7.3 + 0.01 in 1.0 M KNO₃ (supporting electrolyte) at 298 K. Schaap and McMaster method confirmed the formation of 1 : 1 : 1, 1 : 1 : 2 and 1 : 2 : 1 complexes with stability constant trend L-lysine < L-ornithine < L-threonine < L-serine < L-phenylglycine < L-phenylalanine < L-glutamic acid < L-aspartic acid can be explained on the basis of nature of amino acids, size and bonding between metal and ligands.

1 table, 17 ref

007088   Khalaf A A;Awad I M;El-Emary T I;Hassan A K A E A (Chemistry Dep, Faculty of Science, Assiut Univ, Assiut, Egypt, Email: khalafal@aun.edu.eg) : Modern friedel-crafts chemistry. part-29. cyclialkylation of some triphenylated propane, butane and pentane substrates to diphenylated indans under friedel-crafts conditions. J Indian Chem Soc 2008, 85(3), 300-5.

Reactions under Friedel-Crafts cyclialkylation conditions produced : isomeric 1,2-diphenylindans from 1,2,3-triphenyl-(l- or 2-)propanol and 1-chloro-2,3,3-triphenylpropane, trans-2-benzyl-l-phenylindan from 2-benzyl-1,3-diphenyl-2-propanol, isomeric 1-methyl-1,2-diphenylindans from 2,3,4-triphenyl-2-butanol, 1,1-dimethyl-3,4-diphenylindan from 2-methyl-3,4,4-triphenyl-2-butanol, and isomeric 1-ethyl-1,3-diphenylindans from 1,1,3-triphenyl-3-pentanol. Mechanistic interpretations and product identifications are offered.

1 table, 17 ref

007087   Kalidhar S B (Chemistry Dep, Haryana Agricultural Univ, Hisar-125 004, Email: kalidhar@hau.ernet.in) : Distinction between 1,5- and 1,8-dimethoxy anthraquinones using IR of the demethylated product. J Indian Chem Soc 2008, 85(7), 763-4.

When spectral data for a naturally occurring compound suggests two alternative structures involving 1,5-and 1,8-dimethoxy anthraquinones; IR of the demethylated compound helps in choosing the correct structure.

10 ref

007086   Kakati B K;Uptha K R;Verma A (Chemical Engineering Dep, Indian Institute of Technology Guwahati, Guwahati-781 039, Email: anil.verm@iitg.ernet.in) : Numerical optimization of channel and RIB width of proton exchange membrane fuel cell biopolar plate. Int J chem Sci 2007, 5(4), 1590-1602.

Extent of energy generation and its use is the backbone of growth for any country. The problems of limited resources and environmental pollution by fossil fuel have given thrust to the search for the alternative energy generating methods using renewable resources. Fuel cell technology is found very promising as an alternative method for converting chemical energy into electrical energy. Bipolar plate (BP) is one of the key components of proton exchange membrane (PEM) fuel cells with multifunctional character. They uniformly distribute fuel gas and air, conduct electrical current from cell to cell, remove heat from the cell, and prevent leakage of reactant and gases. BP also significantly contributes to the volume, weight and cost of PEM fuel cell stacks. A significant part of the PEM fuel cell stack is the bipolar plates (BP), which account for about 80% of total weight and 45% of fuel cell stack cost. The work is an effort to numerically optimize the channel and rib width of the bipolar plate used for EM fuel cell. A two dimensional mathematical model of the transfer processes in the PEM fuel cell has been developed and analyzed. The channel and rib width of the flow field were varied simultaneously and independently to study the effects on current density, cell voltage and power density of the cell. The rib width of 0.45mm and channel width of 0.5 mm were found to be optimum. The experimental and theoretical results were found to be in well agreement.

5 illus, 30 ref

007085   Jangwan J S;Dobhal M (Chemistry Dep, H.N.B. Garhwal Univ, Campus, Badshahithaul, Tehri-249 199, Email: jsjangwan@yahoo.co.in) : New triterpene glycosides of Clematis montana and their cytotoxic activities. J Indian Chem Soc 2008, 85(3), 313-16.

Two new triterpene glycosides designated as montanosides 1 and 2 were isolated from methanolic extract of Clematis montana. Their structures have been elucidated as 3-O-β-D-glucopyranosyl-oleanolic acid-28-O-β-D-glucopyranosyl-(1→4)-[<97>-L-rharanopyranosyl-(1→2)]-<98>-D-xylopyranoside and 3-O-β-D-glucopyranosyl-oleanolic acid-28-O-β-D-gluco-pyranosyl-(l→4)-[<98>-D-glucopyranosyl-(1→3)-α -L-rhamnopyranopyranosyl-(1→2)]-β-D-xyl opyranoside, respectively by NMR and MS data. Cytotoxic activity of the compounds were evaluated against various squamous carcinoma cells (HSC-2) and human gingival fibroblast cells (HGF). Both of the compounds showed potent cytotoxic activity against the test cells.

1 table, 9 ref

007084   Jain P C;Jain M C;Singh N P (Chemistry Dep, Meerut College, Meerut-250 001, Email: pcjain44@gmail.com) : Oxovanadyl(IV) complexes of 4-benzylamidothiosemicarbazide and 1-α-furyl-4-benzylamidothiosemicarbazone. J Indian Chem Soc 2008, 85(7), 733-4.

Oxovanadyl(IV) complexes of 4-benzylamidothiosemicarbazide (BTSC) and 1-α-furyl-4-benzylamido-thiosemicarbazone (FBTS) have been prepared. The chemical analyses of the complexes correspond to the general formula VO(L)₂Cl₂, where L = BTSC and FBTS.

20 ref

007083   Hooda S;Goyal A K (Chemistry Dep, Acharya Narendra Dev College, Govindpuri, Kalkaji, New Delhi-110 019, Email: sunitahooda@hotmail.com) : Reactivity ratios determination and NMR characterization of 2-hydroxy ethyl methacrylate and methyl methacrylate copolymers. J Indian Chem Soc 2008, 85(8), 818-24.

NMR has proven to be one of the most informative technique for the investigation of copolymer microstruc-ture as chemical shifts are sensitive to compositional and configurational sequences of copolymers. The HEMA/MMA copolymers were prepared by free radical bulk polymerization at 70 °C. The copolymer composition was determined from ^{1H NMR spectrum which is then used to determine the reactivity ratios. The reactivity ratios obtained from KT, EVM and least square methods are r_HEMA = 0.98, r_MMA = 0.82; r_HEMA = 0.88, r_MMA = 0.81 and r_HEMA = 0.92, rMMA = 0.81 respectively. 1H and 13C{1H} NMR spectra were analyzed with the help of DEPT, 2D HSQC and 2D TOCSY spectrum. The long range interactions of carbonyl carbon with methoxy protons and oxy methylene carbon with hydroxyl proton were determined with the help of heteronuclear multiple bond coherence (HMBC) spectrum. With the help of 2D spectra it was found that carbonyl, a-methyl and quaternary carbon of HEMA and MMA unit were sensitive to various configurational sequences as in poly(2-hydroxy ethyl methacrylate) and poly(methyl methacrylate). The carbonyl and oxymethylene carbons showed long range interactions with methoxy and hydroxyl protons respectively.}

7 illus, 1 table, 21 ref

007082   Hiran B L;Chaudhary J;Meena S;Paliwal S N (Chemical Kinetics and Polymer Research Laboratory, Chemistry Dep, Udaipur-313 001, Email: hiranbl@rediffmail.com) : AIBN initiated free radical homopolymerization of N-(1-naphthyl)maleimide and copolymerization with MMA : synthesis and characterization. J Indian Chem Soc 2008, 85(6), 607-14.

Free radical homopolymerization of N-(1-naphthyl)maIeimide (NMI) and copolymerization with MMA were performed in THF at 65 °C with AIBN as the initiator. Nine copolymer samples were prepared using different feed ratios of comonomers. The prepared polymer sample have been characterized by solubility test, intrinsic viscosity, FT-IR and ¹H NMR spectral analysis. The thermal properties have been studied by thermo-gravimetric analysis.

6 illus, 7 tables, 26 ref

007081   Hari Kumaran Nair M L;Siji V L (Chemistry Dep, College Univ, Thiruvananthapuram-695 034, Email: drmlhnair@gmail.com ) : Synthesis, spectral, thermal and antimicrobial studies of oxomolybdenum(V) and dioxomolybdenum(VI) complexes with 2,3-dimethyl-1-phenyl-4-(5-chloro-2-hydroxy-4-methylphenylazo)-5-pyraz olone. J Indian Chem Soc 2008, 85(6), 589-94.

Some novel oxomolybdenum(v) and dioxomolybdenuni(VI) complexes of the formulae [MoO(CMCAAP)Cl₂], [MoO(CMCAAP)(NCS)Cl], [MoO(CMCAAP)(NO₃)Cl], [MoO(CMCAAP)(ClO₄)Cl], [MoO₂(CMCAAP)Cl], [MoO₂(CMCAAP)(NCS)], [MoO₂(CMCAAP)(NO₃)] and [MoO₂(CMCAAP)(ClO₄)] (where CMCAAP = para-chlorometacresolazoantipyrine) have been synthesised and characterized by elemental analysis, molar conductance, magnetic susceptibility data, IR, UV-visible, ESR and ¹H NMR spectral studies. The thermal properties of the complex was investigated by thermogravimetric technique. The ligand and the complexes were screened for their possible antibacterial and antifungal activities. The complexes are found to be monomeric with distorted octahedral geometry.

3 illus, 5 tables, 18 ref

007080   Gupta R L (Agricultural Chemicals Div, Indian Agricultural Research Institute, New Delhi-110 012, Email: rlg_agch@iari.res.in) : Quantitative structure activity relationship study for the nematicidal activity of O,O-diaryl O-n-propyl phosphorothionates. Indian J Chem-Sect B 2008, 47(12), 1882-5.

The relationship between the structure of a series O,O-diaryl O-n-propyl phosphorothionates and their nematicidal activity against Meloidogyne incognita and Rotylenchulus reniforinis has been analysed using physicochemical parameters for hydrophobic, electronic and steric properties of the molecules by means of multiple regression analysis. The QSAR study has revealed that the nematicidal activity against both nematodes is dependent on the steric parameter for length of the para substituent [∑L(p)] and electronic nature [∑σ] of the phenyl ring substituents. Different other parameters i.e. hydrophobicity (∑π) against M. incognita and bulkiness of para substituent [∑MR(p)] and length of meta substituent [∑(m)] against R. reniformis are also found influencing the respective nematicidal activity.

3 tables, 12 ref

007079   Gupta A K;Sindal R S (Chemistry Dep, Jai Narayan Vyas Univ, Jodhpur-342 001, Email: alpanakr@rediffmail.com) : Comparative voltammetric behaviour of isatin and some of its schiff bases at a solid electrode. J Indian Chem Soc 2008, 85(4), 417-24.

The electrochemical behaviour of isatin (1) and its Schiff base, 3-arylimino-2H-iedol-2-ones (2a-g), has been investigated and compared using cyclic (CV) and differential pulse voltammetry (DPV) techniques at glassy carbon electrode (GCE) in different solvent systems. CV of isatin (1) solution in DMF in 0.1 M LiCl showed two irreversible reduction step due to successive transfer of two electrons leading to formation of dioxindole whereas Schiff bases in this system gave a single two-electron transfer irreversible reduction peak at all scan rates studied. This is due to high basicity of nitrogen atom of imine bond, proton abstraction and second electron transfer are both rapid. The product was secondary amine in case of Schiff bases. However, in acidic BR buffer, isatin (1) is preprotonated and showed a single irreversible one-electron reduction wave due to formation of its dimer, isatide. Controlled potential electrolysis was carried out to find the number of electrons transferred and products were isolated and identified by spectroscopy. Kinetic parameters i.e. charge transfer coefficient (α_na), forward rate constant (K_f,h), diffusion constant (D₀^1/2) have also been calculated.

4 illus, 3 tables, 18 ref

007078   Guha S (Polymer Science Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700 032, Email: sguha_sanak@yahoo.co.in) : Dead polyacrylamide of low polydispersity from atom transfer radical polymerization of acrylamide using CuCl/Me₆TREN as catalyst. J Indian Chem Soc 2008, 85(1), 64-70.

Polyacrylamide with a low polydispersity index (PDI) has been obtained by atom transfer radical polymerization of acrylamide. The polymerization was carried out in dimethylformamide-water (50 to 70% DMF by volume). 2-Chloropropanamide, CuCl and tris(2-dimethylaminoethyl)amine (Me₆TREN) were used as initiator, catalyst and ligand respectively. Apart from these reagents, CuCl₂ and LiCl were used as additives with the expectation of increasing the rate of deactivation of the polymer radicals and thus lowering the PDI. The LiCl also helps to keep the polymer in solution at low temperature (ca. 0 °C or below). The polymerization was carried out in the temperature range -20 to 130 °C. Better yield and lower PDI of the polymers are obtained as the temperature is lowered. However, the polymer separates out of the solution at subzero temperatures even in the presence of LiCl. Kinetic study of the polymerization at 0 °C reveals that the conversion is incomplete but the molecular weights increases with increase in conversion. Polymers with PDI =1.15 can be prepared. However, all attempts of chain extension failed, which indicates end group loss.

4 illus, 5 tables, 18 ref

007077   Goel A;Shailja;Ruchi (Chemistry Dep, Kanya Gurukul Mahavidyalaya, Gurukul Kangri Univ, Jwalapur, Hardwar-249 407) : Kinetics and mechanism of oxidation of some aldoses by hexacyanoferrate(III) ions in aqueous alkaline buffered medium. J Indian Chem Soc 2008, 85(3), 286-9.

Kinetics of oxidation of some aldoses like glucose, galactose, xylose and ribose by hexacyanoferrate(III) ions in aqueous alkaline buffered medium has been investigated. The kinetic results indicate the zero-order kinetics in hexacyanoferrate(III) and first-order in aldoses and OH^-. The ionic strength of the medium has no influence on oxidation rate. Various activation parameters were also calculated at four different temperatures : 30, 35, 40 and 45 °C. The corresponding acids were identified as the main oxidation products of the reaction. A suitable mechanism consistent with experimental findings has been proposed.

5 tables, 13 ref

007076   Ganguly N C;Nayek S;Barik S K;Dutta S (Chemistry Dep, Kalyani Univ, Kalyani-741 235, Email: nemai_g@yahoo.co.in ) : Aqueous hydrogen peroxide activated by ammonium heptamolybdate catalyst - a mild clean effective reagent system for the deprotection of oximes, semicarbazones and phenylhydrazones at room temperature. J Indian Chem Soc 2008, 85(7), 711-16.

Oximes, phenylhydrazones and semicarbazones of a wide variety of aldehydes and ketones are cleanly cleaved to the corresponding carbonyl compounds in good to acceptable yields using environmentally safe and convenient oxidizer, 30% hydrogen peroxide in catalytic combination with 20 mol% ammonium heptamolybdate in aqueous acetic acid or tetrahydrofuran at room temperature. Absence of overoxidized by-products in case of oxidation-prone aromatic aldehydes, α,β-unsaturated aldehydes and compatibility with various common functional groups such as hydroxy, methoxy, epoxy, amino, methylenedioxy, conjugated and unconjugated C = C bonds are some of the key advantageous features of the method.

3 tables, 25 ref

007075   Dutta S;Das A K (Chemistry Dep, Burdwan Univ, Burdwan-713 104, Email: arabindakdas@rediffmail.com) : Separation of selected 4f and 5f metals by solid phase extraction. J Indian Chem Soc 2008, 85(1), 9-21.

Paper reviews the solid phase extraction of selected 4f and 5f metals reported by various researchers during the last decade. It is seen that major work has been carried out on uranium and thorium. Literature survey presents in a nutshell the characterization and different parameters for effectiveness of the solid phase extractants, which has been applied for separation of uranium, thorium and lanthanides in different matrices. A discussion of analytical methodologies, applications and analytical characteristics has also been included.

2 illus, 3 tables, 103 ref

007074   Dubey R K;Pathak S (Chemistry Dep, Allahabad Univ, Allahabad-211 002, Email: rajalkoxy@yahoo.com) : Synthesis and characterization of mixed ligand complexes of tin(II) and tin(IV). J Indian Chem Soc 2008, 85(1), 53-8.

Some new and novel complexes of tin(II) and tin(IV) of the type [(sb)SnCl_n-2(sb')] [where sb = Schiff bases; salicylidene-4-methyl-l-aminobenzene (p-smabH), salicylidene-3-nitro-l-amino benzene (snabH); sb' = Schiff bases; 4-nitrobenzylidcne-2-aminophenol (nbaphH), salicylidene-2-aminopyridine (sapH), salicylidene-4-aminoacetophenone (sappheH) and n = 2 for tin(II), 4 for tin(IV)] have been prepared by the interaction of metal chloride with sodium salts of Schiff bases in the presence of benzene-methanol mixture. All these complexes are monomeric in nature. The complexes of tin(II) and tin(IV) are coloured solids with sharp melting points and were characterized on the basis of elemental (C, H, N, Cl and Sn) analysis and spectral [IR, NMR (^{1H, 13C) and FAB-mass] studies.}

1 illus, 3 tables, 23 ref

007073   Dubey R K;Mishra C M;Baranwal P (Synthetic Inorganic and Metallo-Organic Research Laboratory, Chemistry, Allahabad Univ, Allahabad-211 002, Email: rajalkoxy@yahoo.com) : Synthesis, reactivity and physico-chemical properties of novel chloro complex of nickel(II) containing benzoxazole ligand. J Indian Chem Soc 2008, 85(4), 387-94.

New chloro complex of nickel(II) of the type [(μ-Cl)₂Ni₂{η²-(pbox )}₂] (1) has been synthesized by the interaction of nickel(II) chloride with {2-(0-hydroxyphenyl)}-benzoxazole (pboxH) in equimolar ratio (in refluxing EtOH). Further, it was treated with sodium salts of Schiff bases (sb) [sb = smabH and sapH], isopropoxide and aluminiumtetraisopropoxide and aryloxo- and alkoxo-salts in the presence of THF/pyridine to produce new hydrocarbon soluble mixed ligand complexes of the types : [(smab)Ni{η²-(pbox)}] (2), [(sap)Ni{η²-(pbox)}] (3), [(μ-OPr^{i)₂Ni₂{η2< /sup>-(pbox)}₂] (4), [(μ-OAr)₂Ni₂{η2-(pbo x)}₂] (5) and [{(μ-OPri)₂Al(OPri)₂}Ni{ <104>2-(pbox)}] (6). These new products have been characterized by spectroscopic [IR, electronic (UV-visible), FAB-mass] and magnetic studies. A tentative T_d geometry around nickel(II) are proposed.}

1 illus, 2 tables, 21 ref

007072   Drake J E;Hursthouse M B;Kumar R;Light M E; Ratnani R;Saraswat K (Pure and Applied Chemistry Dep, M.D.S. Univ, Ajmer-305 009, Email: ratnaniraju@rediffmail.com) : Synthesis and spectroscopic characterization of bromodioxotriphenylphosphine oxide (N,N'-dialkyldithiocarbamate/O-alkyldithiocarbonate)molybdenum(VI) complexes and the crystal structure of 2,5-dimethylpyridium bromide. J Indian Chem Soc 2008, 85(8), 807-12.

A new series of bromodioxomolybdenum(VI) complexes, MoO₂Br(S₂CNR₂)(OPPh₃) (NR₂ = NEt₂, N(i-Pr)₂, NCH₂(CH₂)₃CH₂) and MoO₂Br(S₂COR)(OPPh₃) (R = Et, n-Pr, i-Pr) were prepared by the reaction of dibromodioxobis(triphenylphosphineoxide)molybdenum(VI) with sodium/potassium salts of the corresponding dithiocar-bamates or dithiocarbonates in 1 : 1 molar ratio in dichloromethane. These newly synthesized complexes were characterized on the basis of elements analysis and spectral (IR and ^{1H NMR) studies. The crystal structure of 2,5-dimethylpyridium bromide is also described. [CMeCHCHCMeCHNH]Br crystallizes as monoclinic in the space group P2₁/c with cell parameters a = 8.6591(9), b = 13.252(1), c = 7.258(1) Angstrum, β = 101.94(1)°, V = 814.9(2) A3, Z = 4, R = 0.0393, R_w = 0.0885.}

2 illus, 4 tables, 33 ref

007071   Dhakar N;Ojha S;Jat J L;Talesara G L (Synthetic Organic Chemistry Research Laboratory, Chemistry Dep, M. L. Sukhadia Univ, Udaipur-313 001, Email: gtalesara@yahoo.com) : Synthesis and characterization of some 3-N-alkoxyphthalimido-5-arylidene-2-{[4-(4-substituted phenyl)-1,3-thiazol-2-yl]imino}-1,3-thiazolidin-4-ones. J Indian Chem Soc 2008, 85(6), 660-4.

4-Chloro/methyl phenacyl bromide 1a-b reacted with thiourea to furnish 2-amino thiazole 2a-b through Hantzsch's process, which were converted to their thiazolidinone derivatives 4a-b, by the reaction of corresponding thiazolyl thiourea 3a-b with chloroacetic acid in the presence of sodium acetate. Subsequent treatment of 4a-b with aromatic aldehydes 5a-c, followed by condensation with (o-bromoalkoxyphthalimides 7a-b afforded titled compounds.

1 table, 10 ref

007070   Dey S P;Dey D K;Dhara M G;Mallik A K (Chemistry Dep, Jadavpur Univ, Kolkata-700 032, Email: mallika52@yahoo.co.in) : Reduction of some flavanones and E-3-benzylideneflavanones under modified clemmensen reduction condition. J Indian Chem Soc 2008, 85(7), 717-20.

A mild and efficient method for reduction of flavanones and E-3-benzylideneflavanones has been developed by using modified Clemmensen reduction condition [Zn(Hg), CH₃COOH, EtOH, reflux, 1.5 h]. Flavanones gave flavans and E-3-benzylideneflavanones gave 3-benzyIflavans and 3-benzyIflav-3-enes.

2 tables, 13 ref

007069   Deshmukh M B;Suryavanshi A W;Deshmukh S A (Chemistry Dep, Shivaji Univ, Kolhapur-416 004, Email: m_deshmukh@rediffmail.com) : Microwave assisted synthesis of 2,4-disubstituted pyrimido-[1,2-a]-benzimidazoles. J Indian Chem Soc 2008, 85(3), 330-2.

A new series of 2,4-disubstituted pyrimidobenzimidazoles were synthesized by conventional as well as microwave methods. The synthesized compounds exhibited moderate to good antifungal and antibacterial activities.

3 tables, 3 ref

007068   Deshmukh M B;Jagtap S S;Deshmukh S A;Jadhav S D;Anbhule P V (Chemistry Dep, Shivaji Univ, Kolhapur-416 004, Email: m_deshmukh1@rediffmail.com) : Synthesis of amino acid derivatives of 2-mercaptobenzothiazole. J Indian Chem Soc 2008, 85(3), 290-2.

The reaction of ethyl benzothiazole-2-yl-thioacetatc and methyl benzothiazole-2-yl-thiopropionate with various amino acids in presence of alkali at 0-5 °C to form peptide has been described.

3 tables, 9 ref

007067   Deshmukh M B;Alasundkar K N;Salunkhe S M; Salunkhe D K;Sankpal S A;Patil D R;Anbhule P V (Chemistry Dep, Shivaji Univ, Kolhapur-416 004, Email: m_deshmukh1@rediffmail.com) : Synthesis of dibenzo-18-crown-6- ether containing pyrimidine derivatives. Indian J Chem-Sect B 2008, 47(12), 1915-17.

The strategy employed for the synthesis of new macro-molecules containing pyrimidine moiety involved acetylation of dibenzo-18-crown-6 (1) to yield 4,4'-diacetyl derivative of dibenzo-18-crown-6 (2) which was further reacted with different aldehydes to give corresponding chalcone 3. Reaction of chalcones 4 with guanidine hydrochloride gives target molecule. The structures of synthesized compounds have been characterized on the basis of spectroscopic data.

12 ref

007066   Desai P S;Vashi R T (Chemistry Dep, Navyug Science College, Rander Road, Surat-395 009) : Methylthymolblue complexon as corrosion inhibitors for aluminum in trichloroacetic acid. J Indian Chem Soc 2008, 85(1), 92-6.

The corrosion of aluminum in trichloroacetic acid (TCA) containing methylthymolblue complexon has been studied. In plain trichloroacetic acid, the corrosion rate increases with the acid concentration. At constant acid concentration, the inhibition efficiency (IE) of methylthymolblue complexon increases with the inhibitor concentration. At constant inhibitor concentration, the IE decreases with the increase of acid concentration. As temperature increases, percentage of inhibition decreases. Plot of log (0/1 - 0) versus log C results in a straight line, suggesting that the inhibitors cover both the anodic and cathodic regions through general adsorption following Langmuir isotherm. The curves show very little anodic but significant cathodic polarization.

3 illus, 3 tables, 23 ref

007065   Dash D C;Mahapatra A;Naik P;Nalik S K; Mohapatra R K;Ghosh S (P.G. Dep of Chemistry, Sambalpur Univ, Jyoti Vihar, Burla-768 019, Email: dhruba_dash@yahoo.co.in) : Synthesis and characterization of UO²⁺₂,ZrO²⁺ and Th⁴⁺ comlexes with 3-(p-substituted aryl)-2-thiohydantoin.. J Indian Chem Soc 2008, 85(6), 595-9.

A few complexes of the type [ML₂(H₂O)₂] and [ThL₂(H₂O)₂(NO₃)₂], where M = UO²⁺₂ and ZrO²⁺; HL = 3-benzylideneimino-2-thiohydantoin, 3-p-nitrobenzylideneimino-2-thiohydantoin, 3-p-methoxybenzylideneimino-2-thiohydantoin, 3-p-chlorobcnzylideneimino-2-thiohydantoin have been synthesized and characterized on the basis of elemental analysis, thermal analysis, conductance, magnetic moment studies and spectroscopic data (¹H NMR, IR and electronic). The results indicate that the complexes of UO²⁺₂ and ZrO²⁺ are hexacoordinated where as those of Th⁴⁺ ions are octacoordinated.

2 illus, 2 tables, 14 ref

007064   Das M;Meikap B C;Saha R K (Chemical Engineering Dep, Indian Institute of Technology Kharagpur, Kharagpur-721 302, Email: mitali_das_iit@yahoo.com) : Dry beneficiation of iron ore and coal in a fast fluidized bed. Int J chem Sci 2007, 5(4), 1691-1700.

Iron ore and coal are the two major raw materials being used by M/S Tata Iron and Steel Co. At Khondabond, the flaky ore had some ore fines containing 4-5% Alumina are rejected /dumped. If these ores could be beneficiated and the alumina content be brought down to 2%, then it is possible to use in Steel Industry. Water being a scarce commodity at Khondbond, dry beneficiation is one such method, which can be explored. Dry beneficiation can also be tried to recover Iron ore from tailings pond. Fine coals are being used in blast furnace injection. The desirable ash content in such practices is about 10-12%. The captive coals can't be used as it contains ash content of 16%. Dry beneficiation technique can be tried to bring down the ash contents from 16% to 12% so that it can be directly in injected in blast furnace. Fast fluidization is typical regime of fluidization being presently used in alumina production and new generation of coal combustors. It is being suggested in the literature that the technique may be employed to dry beneficiate ores and minerals, specially when the sizes are below 0.5-0.8mm. Apart from sludge/slimes disposal in wet beneficiation process, use of large-scale water can be avoided. Air pollution due to discharge of very fines can be minimized with use of improved design of cyclones and bag filters. Some exploratory investigations have been carried out in a fast-fluidized bed with iron ore (containing 4-8% alumina) and coal (16% ash content) to bring down its alumina content to 2-3% and ash below 12% level. As the ore material is fluidized at high velocity in the riser of a fast fluidized bed, the heavier and coarse particles is generally settled at the bottom in a dense zone of the riser while the finer and lighter particle are entrained to the top dilute zone and then via a cyclone is fed back to the bottom of the riser column. Most of the alumina and low ash fine size coals being lighter are expected to move up to the riser and by a natural beneficiation of ores is expected to take place in the riser.

10 illus, 7 ref

007063   Dahiya R;Pathak D;Kaur R (Pharmaceutical Chemistry Dep, Rajiv Academy for Pharmacy, Mathura-281 001, Email: rajivdahiya04@yahoo.co.in) : Synthesis, characterization and biological screening of some new aryloxyacetic acid analogs. J Indian Chem Soc 2008, 85(7), 754-8.

A novel series of 2-(4-bromo-2-formyl-phenoxy)acetyl amino acid and peptide analogs was synthesized by the coupling of 2-(4-bromo-2-formyl-phenoxy)acetic acid with different amino acid methyl ester hydrochlorides, dipep-tide and tripeptide methyl esters using dicyclohexylcarbodiimide as the coupling agent and N-methylmorpholine as the base. Structures of all the newly synthesized compounds were elucidated on basis of IR, NMR and MS spectral data as well as elemental analysis. On pharmacological screening, some peptide derivatives were found to exhibit potent bioac-tivity against gram-negative bacterium Pseudomonas aeruginosa, pathogenic fungus Candida albicans and earthworms Megascoplex konkanensis, Pontoscotex corethruses and Eudrilus sp. Dermatophytes were found to be moderately sensitive towards the newly synthesized analogs. Hydrolyzed peptide derivatives displayed better antimicrobial activity in comparison to corresponding esters.

15 ref

007062   Chowdhury S;Gou S;Chakraborty P;Naskar J P (Chemistry Dep, Jadavpur Univ, Kolkata-700 032, Email: jpnaskar@rediffmail.com) : Planar 2,2'-dipyridylammonium salt : synthesis and structure. J Indian Chem Soc 2008, 85(8), 813-17.

Reaction of 2,2'-dipyridylamine (DPA) with hexafluorophosphoric acid (HPF₆) in methanol generates white rod-shaped crystals of HDPA.PF6,H₂O. The salt is characterised by C, H and N analyses, FT-IR, ^{1H NMR, mass spec-troscopy and molar conductance measurement. The X-ray crystal structure of the salt has been determined. The structure shows that the salt is monomeric. The amine nitrogen is strongly hydrogen bonded with oxygen atom of water. Two pyridyl rings are almost planar which is a rarity in the coordination chemistry of DPA. Semi-empirical AMI calculation was also performed to delve into the novel situation.}

3 illus, 4 tables, 24 ref

007061   Chowdhury P;Ali M A (Chemistry Dep, Visva-Bharati, Santiniketan-731 235, Email: pranesh_02@yahoo.co.in) : Vanadium(V) initiated graft co-polymerization of vinyl monomers onto poly (vinyl alcohol). J Indian Chem Soc 2008, 85(6), 600-6.

The graft co-polymerization of vinyl monomers onto poly(vinyl alcohol) (PVA) by ammonium vanadate (AV) was studied as a function of H₂O₂/AV mole ratio, PVA/monomer weight ratio, sulfuric acid concentration, and reaction time and temperature. The presence of hydrogen peroxide at 2 N H₂SO₄ improves the grafting efficiency of vanadium(V). The optimum time and temperature of the grafting reaction was found to be 3.5 h and 55 °C respectively for the most reactive vinyl monomer studied. FT-IR spectroscopy was used for the confirmation of grafting. The thermal stability of the grafted polymer was evaluated. A generalized reaction scheme has been suggested to elucidate the role of vanadium(v) and hydrogen peroxide.

4 illus, 1 table, 30 ref

007060   Choudhary A;Agarwal S;Sharma V (Chemistry Dep, JNV University, Jodhpur-342 005, Email: drpkvs27@yahoo.com) : Oxidative regeneration of carbonyl compounds from oximes by morpholinium chlorochromate: a kinetic and mechanistic study. Indian J Chem-Sect A 2009, 48(3), 362-6.

The oxidative deoximination of several aldo- and keto-oximes by morpholinium chlorochromate in dimethyl sulphoxide, exhibits a first order dependence on both the oxime and MCC. The oxidation of ketoximes is slower than that of aldoximes. The rate of oxidation of aldoximes correlate well in terms of Pavelich-Taft dual substituent-parameter equation. The low positive value of polar reaction constant indicates a nucleophilic attack by a chromate oxygen on the carbon. The reaction is subject to steric hindrance by the alkyl groups. The reaction of acetaldoxime has been studied in nineteen different organic solvents. The solvent effect has been analysed by multiparametric equations. A mechanism involving the formation of a cyclic intermediate in the rate-determining step has been proposed.

007059   China Raju B (Organic Chemistry Div, Indian Institute of Chemical Technology, Hyderabad-500 607, Email: chinaraju@iict.res.in) : Synthesis of N-(substituted benzyl)-2-(3',5-dimethyl-4'-hydroxyphenyl) acetamides. Indian J Chem-Sect B 2008, 47(12), 1903-5.

4-Benzyloxy-3,5-dimethylphenylacetate 1 reacts with substituted benzyl amines 2a-e affords N-substituted benzyl-2-(4'-benzyloxy-3',5'-dimethylphenyl) acetamides 3a-e, which on debenzylation give N-substituted benzyl-2-(3',5'-dimethyl-4'-hydroxy phenyl) acetamides 4a-e in very good yields which are important intermediates for the synthesis of 1,2,3,4-tetrahydroisoquinolines.

6 ref

007058   Chellamani A;Alhaji N M I (Chemistry Dep, Manonmaniam Sundaranar University, Tirunelveli-627 012, Email: achellamani@yahoo.co.in) : Kinetics and mechanism of (salen)Mn^III-catalysed hydrogen peroxide oxidation of diphenyl sulphides.. Indian J Chem-Sect A 2009, 48(3), 346-51.

The kinetics of (salen)Mn^III complexes-catalysed oxidation of a few diphenyl sulphides by hydrogen peroxide have been investigated at 25<144>C in acetonitrile (80%) - water (20%) spectrophotometrically. The reaction follows first-order kinetics in (salen)Mn^III complex and zero-order kinetics in hydrogen peroxide. The order of the reaction with respect to sulphide is fractional. The effects of nitrogenous bases, free radical inhibitor and changes in solvent composition have also been studied. A suitable mechanism involving a manganese(III)-hydroperoxide complex as reactive species has been proposed.

007057   Chaudhry S C;Verma C;Bhatt S S;Sharma N (Chemistry Dep, Himachal Pradesh Univ, Summer Hill, Shimla-171 005, Email: scchaudhry@sancharnet.in) : 2,4-dinitrophenoxides of zirconium(IV). J Indian Chem Soc 2008, 85(6), 650-3.

Complexes of composition ZrCl_4-n(dnp)_n (where dnp is anion of 2,4-dinitrophenol i.e. OC₆H₃(NO₂)₂-2,4) have been synthesized by the reaction of zirconium tetrachloride with equimolar and bimolar amounts of 2,4-dinitrophenol (dnpH) in toluene under reflux and characterized by elemental analysis, conductivity measurements, infrared and proton NMR spectral studies. Thermal behaviour of these complexes has also been investigated and using TG data, thermodynamic parameters have been calculated. The reaction of the parent complexes with nitrogenous bases such as 1,10-phenanthroline and 2,2'-bipyridyl results in the formation of simple addition compounds characterized by analytical and infrared spectral studies.

1 illus, 1 table, 21 ref

007056   Chandra S;Tyagi M (Chemistry Dep, Zakir Husain College (Delhi Univ), JLN-Marg, New Delhi-110 002, Email: schandra_00@yahoo.com) : Spectroscopic and biochemical studies of chromium(III) and manganese(II) complexes with p-vanillin containing thiosemicarbazone and semicarbazone ligands. J Indian Chem Soc 2008, 85(1), 42-7.

A new scries of chroniium(III) and manganese(II) complexes with p-vanillin thiosemicarbazone (L¹) and p-vanillin semicarbazone (L²) have been synthesized and characterized. The nature of bonding and stereochemistry of the complexes have been deduced from elemental analysis, conductivity measurements, mass, magnetic susceptibility, infrared and electronic spectral studies. On the basis of these spectral studies, an octahedral geometry has been assigned for all the complexes. The antimicrobial activities of the free ligands and their metal complexes were evaluated on different species of phytopathogenic fungi and their biopotency has been discussed.

8 illus, 3 tables, 12 ref

007055   Chandra S;Shukla D;Gupta L K (Chemistry Dep, Zakir Husain College (Delhi Univ), JLN Marg, New Delhi-110 002, Email: schandra_00@yahoo.com) : Synthesis and spectroscopic study of cobalt(II), nickel(II)and copper(II) complexes with N-donor (N₄) macrocyclic ligand (DSLF). J Indian Chem Soc 2008, 85(8), 800-6.

Complexes of Co^II, Ni^II and Cu^II containing a tetradentate macrocyclic nitrogen ligand have been prepared via template reaction of 2,3-pentanedione, w-phenylenediamine and transition metal ions. The complexes have been characterized on the basis of elemental analysis, molar conductance measurements, magnetic susceptibility measurements, infrared, EPR and UV-Visible electronic absorption spectral studies.

7 illus, 5 tables, 27 ref

007054   Chandra S;Raizada S;Rani S (Chemistry Dep, Zakir Husain College (Delhi Univ), JLN Marg, New Delhi-110 002, Email: schandra_00@yahoo.com) : Lanthanide complexes of tetradentate macrocyclic ligand : synthesis and spectroscopic investigation. J Indian Chem Soc 2008, 85(8), 783-91.

The lanthanide complexes derived from (l,5,8,12-tetraaza-2,4,9, 11-tetramethyl cyclotctraaza-1,4,8,11-tetraene) were synthesized. The general composition of the complexes is [Ln(L)X₂,H₂O]X, where Ln = La, Ce, Nd, Sm and Eu and X = NO^{-₃ and Cl-. The ligand was characterized on the basis of elemental analyses, IR, Mass and 1H NMR spectral studies. All the complexes were characterized by elemental analyses, molar conductance measurements, magnetic susceptibility measurements, IR, Mass, electronic spectral techniques and thermal studies. The ligand acts as a tetradentate chelate and coordinates through four nitrogen atoms of azomethine groups. The lanthanum complexes are diamagnetic while the other LnIII complexes are paramagnetic due to the presence of 4fn unpaired electrons. The spectral parameters i.e. nephelauxetic effect (p), covalency factor (b1/2), Sinha parameter (S%) and covalency angular overlap parameter (η) have been calculated from absorption spectra of NdIII and SmIII complexes. These parameters suggest the metal-ligand covalent bonding. In the present study, the complexes show the coordination number seven.}

5 illus, 3 tables, 26 ref

007053   Chandra S;Kumar A (Chemistry Dep, Zakir Husain College, J. L. N. Marg, New Delhi-110 002, Email: schandra_00@yahoo.com) : Synthesis and structural evaluation of transition metal complexes of thiosemicarbazone and semicarbazone derived from pyrrole-2-carboxaldehyde. J Indian Chem Soc 2008, 85(4), 376-80.

Presents the synthesis and characterization of cobalt(II), nickel(II) and copper(II) complexes of thiosemicarbazone (L^{1) and semicarbazone (L2) derived from pyrrole-2-carboxaldehyde. AH the complexes reported here had been characterized by elemental analysis, molar conductance, magnetic moment, IR, electronic and EPR spectral studies. The molar conductance measurements of the complexes in DMSO correspond to non electrolytic nature. All the complexes are of high-spin type. On the basis of spectral studies various six coordinated geometry may be assigned for all the complexes except Co(L)₂(SO₄) and Cu(L)₂(SO₄) [where L = L1 and L2] which are of five coordinated square pyramidal geometry.}

3 illus, 2 tables, 19 ref

007052   Brahmachari G;Jash S K;Gangopadhyay A;Sarkar S;Laskar S;Gorai D (Chemistry Dep, Visva-Bharati Univ, Santiniketan-731 235, Email: brahmg2001@yahoo.co.in) : Chemical constituents of Limnophila indica. Indian J Chem-Sect B 2008, 47(12), 1898-1902.

Two flavonoids, 5,6-dihydroxy-7,8,4'-trimethoxy flavone 1 and 5,2'-dihydroxy-8,3',4'-trimethoxyflavone 2 together with three known compounds, 5-hydroxy-7,2'-dimethoxyflavone 3, 5,2'-dihydroxy-7,8-dimethoxyflavone 4 and β-sitosterol 5, have been isolated from the aerial parts and roots of Limnophila indica (Scrophulariaceae). The structures of compounds 1-5 have been elucidated on the basis of spectral and chemical studies.

1 table, 29 ref

007051   Berar S;Berar U;Thakur M;Gupta S C;Kamboj R C (Chemistry Dep, Kurukshetra Univ, Kurukshetra-136 119, Email: rckamboj@rediffmail.com) : Photochemistry of 3-alkoxy chromones : photocyclisation of 3-benzyloxy-6-chloro-2-(1'-methyl-2'-phenylvinyl)-4-oxo-4H-1-benzopyra n. J Indian Chem Soc 2008, 85(7), 759-62.

Photocyclisation of 3-benzyloxy-6-chIoro-2-(1'-methyI-2'-phenylvmyii)-4-oxo-4H-1-benzopyra n with pyrex filtered UV light to yield linear tricyclic pyranopyrone and angular fused tetracyclic compound is described. The product formation occurred via cyclisation of 1,4-biradical produced through H-abstraction by C = O group and conrotatory 6πe-electrocyclisation.

1 illus, 13 ref

007050   Barbora L;Acharya S;Kaalva S;Verma A (Centre for Energy, Indian Institute of Technology Guwahati, Guwahati-781 039, Email: anil.verma@iitg.ernet.in) : Nafion/TiO₂ composite membrane for direct methanol fuel cell. Int J chem Sci 2007, 5(4), 1579-89.

Nation/TiO₂ composite membranes were prepared by casting method for the possible application in direct methanol fuel cell (DMFC). The composite membranes were synthesized using commercially available nation dispersion and TiO₂ powder calcined at 400°C. Three different loadings of the TiO₂ have been used to prepare the composite nation membrane. The composite membranes were characterized by SEM, ion exchange capacity, water uptake, proton conductivity and methanol crossover or methanol permeability. Nation/TiO₂ composite membranes showed increase in water uptake, ion exchange capacity and proton conductivity values compared to pure cast nation, but the values slightly decreased with increase in TiO₂ loadings above 1%. The TiO₂ composite membranes exhibited a sharp decrease in methanol permeability. The best compromise between proton conductivity and methanol permeability has been found out with the help of characteristic factor and 5 wt% TiO₂ loading has been found optimum for the possible application of the composite membrane in DMFC.

3 illus, 1 table, 18 ref

007049   Bansal O P (Chemistry Dep, D.S. College, Aligarh-202 001, Email: drop31@rediffmail.com) : Effect of different organic material on lead adsorption in soils of Aligarh district. J Indian Chem Soc 2008, 85(1), 59-63.

The effect of different organic material (FYM, sewage sludge and poultry litter) on adsorption-desorption of lead on three soil samples of Aligarh district was studied. The adsorption isotherms were of 'L' type and adsorption-desorption data conformed to Freundlich isotherm equation. The adsorption increased with the increase in organic material and followed the order : sewage shudge > FYM > poultry litter. The adsorptivity of soils was in order : Soil No. 1>2>3. The adsorption capacity was significantly positively correlated with soil organic carbon and soil-clay-content. The desorption of lead was more by CaCl₂ than water and followed the order : soil 3 > 2 > 1. The desorption of lead decreased with the addition of organic material suggesting a less availability of lead to crops grown on such soils. The complete desorption of lead did not take place.

2 illus, 2 tables, 11 ref

007048   Aswani Kumar M;Kunzru D (Chemical Engineering Dep, Indian Institute of Technology Kanpur, Kanpur, Email: dkunzru@iitk.ac.in) : Alumina washcoating of cordierite monoliths using sol-gel method. Int J chem Sci 2007, 5(4), 1561-8.

Washcoating of alumina on cordierite monoliths by sol-gel method has been investigated. The influence of the solid concentration and viscosity of the sol was studied. The sol viscosity was modified by adding polyvinyl alcohol to the sol. Wash coat loading increased with solid concentration and viscosity of the sol. At low viscosities, penetration of the sol into macro-pores of the monolith was observed, which leads to non-uniform active metal distribution. At higher viscosities, sol penetration into the cordierite was reduced. The washcoat reproducibility, uniformity and adhesion decreased drastically with an increase in the viscosity of the sol.

7 illus, 14 ref

007047   Ali I;Singh P D (Chemistry Dep, B. N. College, Patna Univ, Patna-800 004) : Synthesis and characterisation of palladium(II) and platinum(II) complexes with triphenylphosphine sulphide and triphenylstibine. J Indian Chem Soc 2008, 85(4), 440-2.

The complexes of palladium(II) and platinum(II) with triphenylphosphine sulphide (Ph₃PS) and triphenylstibine (Ph₃Sb) of composition [ML₂X₂] (M = Pd^{II, PtII; L = Ph₃PS or Ph₃Sb and X = Cl, Br, I or SCN) have been prepared and characterized. The triphenylstibine sulphide complexes like former ligand could not be isolated as the ligand get desulphurized in aqueous medium and the complexes of desulphurized ligand triphenylstibine have only been isolated in pure form. The complexes have been characterized by UV, IR, 1H NMR spectroscopic methods and resembles with square planar geometry.}

1 table, 10 ref

007046   Alagumuthu G;Ranjit Singh A J A;Sundar S (Post Graduate and Research Dep of Chemistry, Sri Paramakalyani College, Alwarkurichi-627 412, Email: alagupathi@yahoo.co.in) : Kinetics and thermodynamics of fluoride ion sorption on fire clay from aqueous solution. J Indian Chem Soc 2008, 85(1), 111-3.

The kinetics and thermodynamics of fluoride ions sorption on fire clay from aqueous solution have been investigated. The various factors that influence the defluoridation efficiency of the material were studied. Adsorption obeyed both Langmuir and Freundlich isotherm models. Various thermodynamic parameters such as ΔG°, ΔH° and ΔS° were calculated indicating that this system was a spontaneous one and endothermic in nature. FTIR studies showed the involvement of hydroxyl group on the surface in the adsorption interaction.

3 illus, 3 tables, 9 ref

007045   Aidhen I S;Satyamurthi N (Chemistry Dep, Indian Institute of Technology Madras, Chennai-600 036, Email: isingh@iitm.ac.in) : Synthesis of a stable, storable and differentially protected acyclic precursor of D-amicetose and its conversion to 4-O-benzyl-protected D-amicetose. Indian J Chem-Sect B 2008, 47(12), 1851-7.

Two carbon chain homolgation of enantiopure four carbon erythro configured iodo derivative 5 with N-methoxy-N-methyl-2-phenyisuIfonylacetamide 6 affords for the first time a stable and storable precursor 3 of D-amieetose in the acyclic form, wherein the sensitive aldehyde is masked as a Weinreb amide. The differential protection in this acyclic derivative offers all the potential to exclusively arrive at the pyranose form of the target dideoxy-sugar.

2 illus, 12 ref

007044   Ahmad N;Malik M A;Hashmi A A;Khan Z (Chemistry Dep, Jamia Millia Islamia (Central Univ), New Delhi-100 025, Email: drkhanchem@yahoo.co.in) : Effect of ethylenediaminetetra acetic acid, 2,2'-bipyridyl and managanese(II) on the reduction of chromium(VI) by D-glucose in presence of HClO₄. J Indian Chem Soc 2008, 85(8), 836-41.

Kinetic data for the chromium(VI)-D-glucose redox system in presence of complexing agents are reported for the first time. The reaction is first-order each in [Cr^{VI] and [D-glucose]. The kinetics reveal complex order dependence with [HC1O₄]. The zero-order kinetics with respect to [HC1O₄] at low concentrations shifts to higher order at higher concentration. Ethylenediamminetetra acetic acid (EDTA) and 2,2'-bipyridyl (bpy) catalyze the reaction whereas MnII has no effect In the EDTA- and bpy-catalyzed paths, CrVI-EDTA and CrVI-bpy complexes have respectively been suggested as the active oxidant species. On the basis of various experimental data and the product characterization, the most plausible mechanisms have been proposed for the reactions.}

1 illus, 2 tables, 19 ref

007043   Ahamad K U;Jawed M (Civil Engineering Dep, Indian Institute of Technology Guwahati, Guwahati-781 039, Email: jawed@iitg.ernet.in) : Adsorptive capacity of wooden charcoal used in indigenous household iron filters of Assam (India). Int J chem Sci 2007, 5(4), 1623-33.

People in Assam use indigenous household iron filter units - developed using wooden charcoal and sand to remove excessive iron (1 to 10 mg/L) present in ground water. The work evaluates adsorptive capacity of wooden charcoal for Fe(II) removal. The experiments were carried out using synthetic water containing 5-10 mg/L of Fe(II) at a fixed pH of 5.5 and in absence of dissolved oxygen. Batch kinetic studies indicated rapid Fe(II) adsorption in the first 30 min. and yielded a rate constant of 0.0135 min^-1. The adsorption process seems to be governed by diffusion within the pores of charcoal and the mechanism of Fe(II) removal appeared to be complex. The Fe(II) adsorption on charcoal was observed to be favorable and equilibrium data fitted better into Langmuir isotherm. The adsorption breakthrough studies yield decreased volume of treated water at the breakthrough as well as reduced service time with increase in flow rate and decrease in bed depth. The bed depth service time (BDST) analysis for predicted and experimental values were observed to be in good agreement.

5 illus, 2 tables, 33 ref

007042   Agrawal U C;Nigam H L (C1 295A, Indira Nagar, Kanpur-208 026) : Molecular machines based on transition metal complexes : rotaxanes and catenanes. J Indian Chem Soc 2008, 85(7), 677-90.

Human beings since ambiguity have been persistently designing mechanical devices which can perform certain functions useful to them. Recently along with this endeavour, emphasis has also been directed towards miniaturizing these devices leading to the possibility of constructing machines on nanoscale level, but for the past four decades it has been realized that miniaturization has reached its practical and fundamentals limit. Owing to the progress made to better understanding of the operation and mechanism of natural molecular machines of the biological world, it has however become possible to artificially design simple prototype of such device using molecular machines which provide atom-by-atom (bottom-up) approach towards the construction of microdevices. These imitate biological systems which play essential roles in a wide variety of biological events particularly those related to the activities of cells and realize specific functions through their reponses of mechanical motions. Such studies have led to an enormous interest not only in basic research but also in the growth of nanosciences, in particular, towards designing molecular machines using "bottom-up" rather than 'top-down' approach. These are based on the synthesis of various molecular rotaxanes, catenanes, rotors, and other systems. In synthesizing the latter, various systems have been proposed based on redox reactions (electro-chemical; chemical) involving in particular the formations of dissociation of transition metal complexes. It will not be out of place to refer that a very large volume of work has also been carried out using organic and inorganic molecules. Attempts have been made to describe a few examples of Cu^I, Cu^II, Ru^II, Zn^II and other metal complexes using electrochemical, chemical and light-driven molecular motions. However the review will not be a complete one in any sense because of the very large and fast work going on in this area.

16 illus, 3 ref

006160   Wu Y;Luo L (Materials Chemistry Dep, Nanchang Hangkong University, NanChang 330063, PR China, Email: wuyuehui_c@ sina.com) : Preparation of La_0.95Ce_0.05CoO₃ with large surface area. Indian J Chem-Sect A 2009, 48(2), 202-5.

The perovskite-type complex oxides, La_0.95Ce_0.05CoO₃, have been prepared by glycine polyacrylamide sol-gel combustion method, glycine sol-gel method and solid state reaction method. These oxides have been used successfully for combustion of methane. The La_0.95Ce_0.05CoO₃ samples have been investigated by XRD, BET,O_2-TPD and H_2-TPR. The effect of preparation method on the structure and performance of the catalysts has been studied. La_0.95Ce_0.05CoO₃ prepared by glycine polyacrylamide sol-gel combustion method shows the highest catalytic activity for combustion of methane.

006159   Verma A;Joshi A G (Electronic Materials Div, National Physical Laboratory, New Delhi-110 012, Email: amitaverma75@gmail.com) : Structural, optical, photoluminescence and photocatalytic characteristics of sol-gel derived CeO_2-TiO₂ films. Indian J Chem-Sect A 2009, 48(2), 161-67.

CeO₂-TiO₂ films with different Ce/Ti mole ratios have been obtained using a simple sol-gel process. The films (1:0.25 and 1:0.5) containing more than 50% CeO₂ content show nanocrystalline characteristics. X-ray photoelectron spectroscopic study shows the variation of Ce⁴⁺/Ce³⁺ ratio with increasing TiO₂ content. Films with greater CeO₂ content exhibit higher porosity. The observed photoluminescence in the films is attributed to various defects resulting from crystallization and also to the relative amount of Ce³⁺ in the mixed oxide matrix. The transparency in the films appears to be inversely related to their photoluminescence activity, since the 1:0.5 film, which exhibits the best photoluminescence response, is incidentally also the least transparent film. The presence of photocatalytic activity in these films shows their potential use as an efficient photocatalyst.