Research Journal of Chemistry and Environment

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Research Journal of Chemistry and Environment

An Ab Initio Study of XNOy and XPOy (X = H, F, Cl, Br and y = +1, 0, -1) Interstellar Species

Sharma U. and Guha S.*

The ground states of interstellar XNOy and XPOy (X = H, F, Cl, Br and y = +1, 0, -1) systems have been examined using ab initio electronic structure calculations at the B3LYP level with different basis sets using Density Functional Theory (DFT). The geometries have been optimized through the 6-311++G(3df,3pd) level and vibrational frequencies calculated using the 6-311++G(3df,3pd) basis set. The energetic properties of XNOy and XPOy (X = H, F, Cl, Br and y = +1, 0, -1), systems are also examined. The adiabatic ionization potentials of HNO, FNO, ClNO and BrNO are calculated to be 235.2, 294.6, 266.7 and 253.4 kcal mol-1, respectively, while those of HPO, FPO, ClPO and BrPO are 237.3, 274.3, 250.9 and 244.7 kcal mol-1, respectively. Electron affinities for the XNOy and XPOy (X = H, F, Cl, Br and y = +1, 0, -1), species have also been calculated. Dissociation of HNO into H + NO will require 45.6 kcal mol-1 energy and the N-O bond energy is 228.5 kcal mol-1. Structural and energetic details of the cation and anion of XNO and XPO, using the DFT method, are reported for the first time. To our knowledge, this paper also provides the first computational estimates of the structural and energetic properties of the cationic and anionic forms of the halide counterparts of XNO and XPO (X = H, F, Cl, Br).

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The study of CH4-CO2 reforming to syngas over carbonaceous catalyst modified with H2O2

Guo Fengbo1,2, Zhang Yongfa1*, Zhao Haixiang1 and Zhang Guojie1

The CH4-CO2 reforming was performed in a Fixed-bed reactor over carbonaceous catalyst modified with H2O2 ,the influence of H2O2 concentration, reaction temperature, ratio of CH4/CO2 and gas-solid contact time on the conversion of CH4 and CO2 and product gas H2/CO were investigated. IR and SEM were employed to characterize the carbonaceous catalyst. It can be seen from the IR spectrum that the oxygen groups of C-O and C=O of the carbonaceous catalyst increased significantly after the treatment of H2O2 high-pressure and high-temperature hydrothermal reaction. The results show that the performance of the carbonaceous catalyst modified with H2O2 is better than the carbonaceous catalyst unmodified under the same conditions in CH4-CO2 reforming. The conversion of CH4 and CO2 increased with the reaction temperature and gas-solid contact time. The conversion of CH4 decreased with the increasing ratio of CH4/CO2, the ratio of H2/CO can be changed by the ratio of CH4 and CO2, using the 5% H2O2-modified carbonaceous catalyst, at the reaction temperature of 1000℃ the ratio of CH4/CO2=1:1, total flow 35.5ml/ min, the conversion of CH4 and CO2 were 98.88% and 99.42%.

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Synthesis of Nanostructured Polyaniline in Dodecyl Sulphuric Acid (DSA) mediated Miceller Medium with Isopropyl Alcohol as Cosurfactant

Ahmed N., Upadhyaya M. and Kakati D. K.*

Intrinsically conducting polymers including poly-aniline (PANI) have received considerable attention owing to their wide ranging applications. An emer-ging area of research in conducting polymers is the nanosized conducting polymers. Nanostructured poly-aniline1 has been synthesized by the use of hard templates2,3, soft templates4, electro-spinning5,6, inter-facial polymerization1,7, emulsion polymerization8,9 etc. Here in, we report the synthesis of nanostructured polyaniline in a miceller medium based on dodecyl sulphuric acid (DSA), acting as surfactant as well as dopant and cosurfactant isopropyl alcohol at varying surfactant molar concentration and ammonium peroxydisulfate (APS) to aniline molar ratios. The nanostructured polyaniline was characterized by UV –Vis spectroscopy, Fourier transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The distribution of particle size was determined by dynamic light scattering (DLS) studies. The conductivity was measured by the standard Four–Probe technique.

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A study on Nitric Acid treatment on Chloroform

Mallick Abhijit

Chloroform is an organic substance and polar in nature. Inorganic acids like HNO3 are also polar in nature. An experimental study was conducted to investigate the nature of chemical reaction between chloroform and concentrated nitric acid. Chloroform-nitric acid mixture appears as a heterogeneous mixture with two layers, aqueous and organic. Preliminary investigation shows that colourless organic phase, i.e., chloroform, gains a faint green colour after nitric acid treatment. Silver nitrate treatment of the aqueous phase of heterogeneous chloroform-nitric acid mixture clearly indicates that Cl- is formed during the chemical reaction between chloroform and nitric acid. IR study of the organic phase of heterogeneous chloroform-nitric acid mixture clearly indicates the presence of aldehyde group(-CHO) in the organic phase. The aldehyde group is further confirmed by Tollens reagent. On the basis of experimental studies, a probable mechanism is proposed to explain the reaction between chloroform and nitric acid. The mechanism shows that chloroform, when treated with nitric acid, is converted to chloroformaldehyde.

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Gum Acacia and Starch based Prodrugs: Preparation and Drug Release Studies

Byakod N.V.* and Lonikar S.V.

Prodrugs of Gum acacia and Starch conjugated with nonsteroidal anti-inflammatory drugs such as Ibupr-ofen, Aspirin and Norfloxacin were prepared by varying the amount of drug. Prodrugs were prepared in two stages. In the first stage drug was converted to its acid chloride derivative and subsequently reacted with polymer in the second stage. These prodrugs were characterized by IR and 1H-NMR spectroscopy. The release rate of drugs was studied in-vitro at two different pH 1.2 and 7.4 spectrophotometrically in presence and in absence of enzymes. Drug release was much slower in presence and in absence of enzymes at pH 1.2 and without enzymes at pH 7.4 (Less than 15%).In presence of enzymes at pH 7.4 the release rate was seen to decrease with increase in drug content.

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Bridging Precursors of Yttrium with Lawsone monoximates

Gaikwad Sanjay Dattatray

New two complexes of Yttrium(III) with lawsone monoxime and phthiocol monoxime as [Y2(μ-L2)L4.4H2O] have been synthesized and characterized via Ele-mental Analysis, TG, IR,1H NMR, Electronic and Magnetic Susceptibility techniques. These complexes are yellow and brown in colour. The study showed the bridging mode of the complex with two nuclei. The distorted antiprismatic geometry is suggested for both Y1 and Y2 complexes. Such type of bridging precursors have great importance, they may be used as chemical sensors1, electroceramics2 or zeolite type materials3.

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Rapid Spectrophotometric Determination of Molybdenum in Steel and Environmental Samples after Extraction of its 6-Chloro-3-Hydroxy-2-(4’-Methylphenyl)-4H-Chromene-4-one Complex

Kapoor J. K.,1* Dass R.2 and Gambhir S.3

An extractive spectrophotometric method has been developed for micro determination of molybdenum. In 5M acetic acid medium, molybdenum (VI) forms a yellow colored (1:2) complex with 6-choloro-3-hydro-xy-2-(4’-methylphenyl)-4H-chromene-4-one (CHMC). The complex is quantitativ¬ely extractable into toluene and absorbance of the extract is measured at λmax 424 nm. The Beer’s law range is 0-2.40µg Mo ml-1 with molar absorptivity and Sandell’s sensitivity of 5.52 x 104l mol-1 cm-1 and 0.00167µg Mo cm-2 respectively. The effect of large number of cations, anions and complexing agents is studied. Out of these only hydro-gen peroxide, citrate, oxalate, disodium EDTA, Sn (II) and Ce (IV) interfere seriously. For ten replicate determinations of 1 g Mo ml-1, the standard devia-tion is 0.008 absorbance units with a relative mean error of ± 0.08%. The method has been applied satisfactorily to the determination of molybdenum in various alloy steels and wide variety of environmental samples including different types of water samples.

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Removal of copper (II) from aqueous solutions using Leucas aspera leaf powder

Mumtazuddin S.1*, Azad A. K. 1 and Chaudhary N. L.2

The biosorption of copper ions from aqueous solution by Leucas aspera leaf powder (LSLP) was studied in a batch set up as a function of contact time, pH, copper ion concentration and adsorbent dosage. The Lang-muir and Freundlich adsorption models were applied to describe the isotherms and isotherm constants. The biosorption data gave a good fit with Langmuir and Freundlich isotherms with maximum adsorption capa-city of 97.2 mgg-1 of copper ion on Leucas aspera leaf powder. The kinetics of interaction was properly correlated with the second order kinetic model. The results show good potentiality of using L. aspera leaf powder as a biosorbent for the removal of Cu (II) from aqueous solutions.

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Study on Vertical Alignment of Carbon Nanotubes using AFM and SEM

Singh Sudhanshu1, Bharadwaj Lalit M.2, Mahna Satish K.1, Kaur Inderpreet2 and Garg Sumita1

In recent years, carbon nanotubes (CNTs) have attracted and continue to attract considerable interest in a wide variety of scientific files. Especially well-arrayed CNTs are highly desired to prepare chemical sensors, nanoprobes for scanning probe microscopy, field emitter devices. We performed the vertical alignment of single-walled carbon nanotubes (SWNTs) in silica, mica and glass surfaces. CNTs have been functionalized successfully using microwave method, conventional sonication method and we found out that sonication was the better technique among all of them and was confirmed by Fourier Transform Infrared Microscopy (FTIR). For chemical reaction with chemical modified glass surface, the carboxylic acid groups were converted into acid chloride groups followed by the chemical reaction with chemically functionalized surfaces. Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) results show the vertically aligned SWNTs and the distribution of the vertically aligned SWNTs becomes denser as reaction time increases. Alignment of the shorter nanotubes on the substrate increases with increase of reaction time (e.g. SWNTs of length 0.5 to 2µm are easier to align than the SWNTs of length 200µm). So we conclude that SWNTs are vertically aligned on chemically functionalized glass substrate by controlling chemical reactivity. Tall and smaller diameter CNTs are difficult to align on substrate without support of neighbouring Carbon Nanotubes.

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Surveilence of point source wastewater discharges to trace metals pollution in the marine environment

Bu-Olayan A.H. * and Thomas B.V.

This study describes the investigation on the major trace metals levels in wastewater discharges and sediment in the vicinity of twenty four permanent and five semi-permanent wastewater drain outlets into the Kuwait coast. Analytical perfection of completely digesting the sediment samples was achieved by using the State-of-the-Art technology driven microwave digester. Results showed high trace metal levels in sediment than in wastewater and during winter than in summer irrespectively of the sampled areas. The point source of discharge outlets categorized by Kuwait Governorates (GI-GVI) revealed high trace metal levels in GI indicating rapid industrialization and accidental discharge of untreated wastewater into the marine environment. High Zn and Cr in both the sediment and wastewater samples indicated the presence of oil spills and diverse waste products dumped into the sea. Results indicated trace metals in wastewater exceed the permissible limits of statutory pollution standards that may be characterized as a major issue applicable to similar polluted areas in other countries.

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Microwave-induced increase of amide I and amide II vibration bands and modulating functions of sodium-chloride, sucrose and trehalose aqueous solutions: The case study of Haemoglobin

Calabrò Emanuele 1*, Magazù Salvatore 1 and Campo Salvatore 2

The effects of microwaves (MWs) on the secondary structure of haemoglobin were investigated by means of Fourier Transform Infrared (FTIR) Spectroscopy. A set of samples of 250μl of different hemoglobin aqueous solutions (also in the presence of sucrose, trehalose and NaCl) were exposed for 3 hours to 900 MHz mobile phone MWs at a magnetic field intensity around 18 mA/m. Quantitative spectral analysis revealed significant increases in intensity of amide I and II modes after exposure to MWs for haemoglobin in bidistilled water, but not for hemoglobin in sodiumchloride, sucrose and trehalose aqueous solutions. Indeed, MWs interaction with the α-helix structure increases its dipole moment, produces increases in intensity of amide I and II modes whose major contribution is related to the α-helix content. This effect did not result to be significant for haemoglobin in sodium chloride, sucrose and trehalose aqueous solutions.

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2,6-Bis(4-sulpho-1-hydroxy-2-naphthylazo)pyridine: Spectrophotometric Reagent for the Trace Determination of Zinc in Biological Samples

Sharma Ashok K.1*, Kadyan Partap Singh 2 and Singh Ishwar 2

A simple, sensitive and highly selective method is proposed for the determination of zinc (II) using a bis-azo dye, 2,6-bis(4-sulpho-1-hydroxy-2-naphthylazo) pyridine, sodium salt(PBS) as spectrophotometric reagent. At pH 6.6, in aqueous medium the complex is found to obey Beer's law up to 2.4mg/L with an optimum concentration range between 0.64 to 2.0mg/L. Sandell’s sensitivity of the color reaction was calculated to be 0.0012μgcm-2 with molar absorptivity of 5.3x104 L.mol-cm- at 560nm. The optimum conditions for the determination of Zn (II) with the reagent were ascertained. The complexation at different pH was studied in aqueous medium. The composition of the complex is 1:2. The action of some interfering ions was verified and the developed method applied successfully for the estimation of zinc levels in biological samples and the results were then compared with those obtained by using AAS.

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DFT Study on a Fullerene doped with Ge and Sn

Hossein Shirani Il Beigi

DFT calculations are applied for some stable C60, C59 Ge and C59Sn heterofullerenes in this paper. Sn and Ge atoms are doped at the same position of C60. Com-putations are carried out at the B3LYP/cc pVDZ levels. In this work the effects of the heteroatoms, Ge and Sn on the structural properties of the fullerene have been studied. The structure, energetic and relative stabilities of the compounds were compared and analyzed with each other. In addition, vibrations spectra of proposed stable neutral species, as well as the infrared intensities are calculated. From the data obtained from calculation, we found that there is strong correlation between the stability of pure C60 fullerene molecule and the numbers of different C–C bonds.

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Development and validation of HPLC method for the determination of amygdalin in the plant extract of plum kernel

Savic Ivan M.,* Nikolic Vesna D., Savic Ivana M., Nikolic Ljubisa B. and Stankovic Mihajlo Z.

A HPLC method was developed, validated and applied for the determination of amygdalin in the plant extract of plum kernel. The effects of mobile phase composition, stationary phase types and organic modifiers on retention factors of amygdalin were investigated. The chromatographic column used was 5μm SUPEL-CO Analytical HS-C18 column (4.6×250mm), the mobile phase being water: acetonitrile (25:75v/v)), held at 25ºC. Analysis was run at a flow-rate of 0.9cm3•min–1 and at a detection wavelength of 215nm. The results showed that the peak area responses are linear within the concentration range of 10-100μg cm−3 (r=0.9986). The method yielded good results with a quantitation limit of 3.49µgcm-3 and a detection limit of 1.06µgcm-3. The intra-day and intra-instrument reproducibility, RSD were 0.07-0.78 and 0.85-1.62 respectively. The accuracy results of 80%, 100% and 120% amygdalin were 102.8%, 97.74% and 98.36%, respectively. The method is linear, quantitative and reproducible and could be used as a more convenient, efficient and economical method for the trace analysis of amygdalin in the plant extract of plum kernel.

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Kinetics and Mechanism of Oxidation of Phenols by Benzyltriethylammonium Chlorochromate in the Presence of 1, 10-Phenanthroline As Catalyst

Rajalakshmi K.,1* Ramachandramoorthy T.2 and Srinivasan S.3

The catalytic activity of 1, 10-phenanthroline (phen) in Cr(VI) oxidation of phenols has been studied in 60% acetic acid-water medium. The Cr(VI) phen complex is believed to be the probable reactive electrophile in the catalyzed oxidation. The catalytic activity is quite likely to shift the redox potential of the oxidant. The reaction is first order with respect to substrate, catalyst and oxidant. Increase in acidity as well as increase in the dielectric constant increases the rate of the reaction. The added acrylonitrile has no effect on the reaction rate, indirectly indicating the absence of free radical mechanism. The products of oxidation are the corresponding p-benzoquinone. Based on the kinetic results and product analysis, a suitable mechanism has been proposed.

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Novel synthesis of (Methoxy) 2H-3-Aryl-3, 4-dihydro-1,3 benzoxazine and 2H-3- Aryl-3, 4-dihydro-4-methyl-1, 3 benzoxazine

Indorkar Dilesh*, Chourasia O.P. and Limaye S.N.

Benzoxazines are studied due to their potential utilities in pharmacology and photography. The reported methods for the synthesis of substituted benzoxazine derivatives 2-Hydroxy3-methoxy benzaldehyde and 1-(2-Hydroxyphenyl) ethanol on the reaction with different primary aromatic amines gave methoxy 2-(arylimino) methylphenols and 2-[1-arylimino) ethyl] phenols respectively. Synthesized compound (1) on reduction with sodium borohydride gave 2-(arylamino) methylphenols and 2-[1-(aryl amino) ethyl] phenols. Synthesized compound (2) further cyclised with formaldehyde to form the final synthetic derivatives as 2H-3-aryl-3, 4-dihydro-1, 3-benzoxa-zines and 2H-3-aryl-3, 4-dihydro-4 methyl- 1,3-benzoxazines.

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Transition Metal Complexes of 2-[(2,6-Dichlorophenyl)-Amino]Benzene Acetic acid: Synthesis, Spectral Characterization and Antimicrobial Activity Studies

Kulkarni Dilip R.1*, Jahagirdar Mandar M.1 and Deshpande Madhavrao N.2

Complexes of the type [M(DAPA)Cl]2H2O and [M(DAPA)(H2O)2Cl]Cl] where DAPA = 2-[2, 6-dichlorophenyl) amino] benzene acetic acid has been synthesized and characterized by physico-chemical analysis, spectral methods, TGA/DTA and X-Ray diffraction studies. Complexes have 1:1 stoichiometry and square planar and octahedral geometries indica-ting mononegative tridentate nature of the ligand. 1HNMR and IR spectra suggest involvement of carboxylic and secondary amine groups in coordi-nation. EPR spectra support for misalignment of tetragonal axes and TGA/DTA revealed the stability of the complexes in the order as Cu(II) > Co(II) > Cr(III). X-Ray diffraction study corresponds to tetrag-onal crystal system for Cu (II) while monoclinic crystal system for Co (II) and Cr (III) complexes. Moderate antibacterial and antifungal activities have been evaluated against selected gram positive and gram negative bacteria and pathogenic fungi.

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Interaction of Guanine with [Cu(II)(Salgly)H2O] and [Cu(II)(Salhis)H2O] : UV/Visible, Fluorescence and Electrochemical studies

Das Biva* and Medhi Okhil K.

Metal atoms and metal complexes can coordinate to electron donor groups of the nucleo bases and thereby influence the canonical DNA structures propagating the formation of mispairs of DNA. Guanine is an important nucleo base and its coordination behaviour with copper complexes [Cu(II)(Salgly)H2O] and [Cu (II)(Salhis)H2O] have been studied by various spec-troscopic and electrochemical techniques. One guanine is found to bind to the complexes with high binding constant. Guanine binding makes the redox potential of Cu(II)/Cu(I) couple shifted towards negative direction. In cationic and anionic charged environment, provided by surfactant micelles, redox potential of the Cu(II)/Cu(I) couple was found to shift in positive (by 0.050 V) and in negative (by 0.025 V) direction.

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Synthesis of Substituted 2, 4-Diiminobiuret and N-Substituted 1,2,4,6-Thiatriazepines

Tayade D. T.

Heterocycles and heteroacycles containing nitrogen, sulphur and oxygen in the ring have their own importance in pharmaceutical drug and synthetic chemistry. Diiminobiurets and 1,2,4,6-thiatriazepines and their derivatives had been reported to exhibit remarkably. Taking all these things into consideration, recently in this laboratory 1-thioa-mido/N-substituted thioamido-5-N-substitutedamido-2,4-diiminobiurets (III) was synthesized and succe¬ssfully oxidatively cyclised into N-substituted 3,5-diimino-7-(substitutedamino) -4,5-dihydro-1,2,4,6 thiatriazepines( IV) by using iodine as a oxidizing agent .Justification and structure determination of synthesized drugs were carried out by elemental and chemical characteristics and through IR and NMR Spectral data.

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Synthesis, X-ray structure and spectroscopic characterization of a non-stoichiometric nanostructured silver salt hosting water-guest molecules

Nenwa J.1*, Gouet Bebga2, Djonwouo P. L.1 and Fokwa B. P. T.3

The non-stoichiometric salt {Ag2.3K0.7[Co(C2O4)3]. 3H2O}n (1) has been synthesized in aqueous solution and characterized by elemental analysis, single crystal X-ray structure determination, IR and UV-VIS spectroscopies. Compound 1 crystallizes in a monoclinic system, space group C2/c, with unit cell parameters a = 17.901(2), b = 14.592(2), c = 12.157(1) Å, β = 114.287(2)°, V = 2894.4(6) Å3, Z = 4. In the crystal structure, the Co(III) centers are hexacoordinated by the oxalato-O atoms in a distorted octahedral geometry. The structure is best described as a coordination polymer where the host lattice is constructed by the three-dimensional interconnectivity of the metallic centers through the O atoms of the oxalates and waters. The metal-organic framework (MOF) thus formed delineates nanochannels parallel to [001], hosting water molecules of crystallization.

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Oxidation of benzyl ethers by N-bromoisonicotinamide in aqueous acetic acid medium: A Kinetics and Mechanistic Study

Balasubramaniyan M.* and Mathiyalagan N.

Kinetics of oxidation of benzyl ethers by N-bromoiso-nicotinamide (NBIN) in aqueous acetic acid medium in the presence of perchloric acid has been investigated by iodometric method. The observed rate of oxidation is first order in [NBIN] and zero order in both [benzyl ethers] and [HClO4]. An increase in the dielectric constant of the medium increases the rate. The variation of ionic strength has no significant effect on the reaction rate and addition of isonicotinamide has a slight retarding effect on the reaction rate. The stoichiometry of the reaction is found to be 1:1. The corresponding benzaldehyde has been identified as the product of oxidation. It fails to induce polymerization of acrylonitrile under the experimental conditions employed. The Activation parameters for the reaction have been evaluated from Arrhenius plot by studying the reaction at different temperature. A suitable scheme is proposed and an appropriate rate law is deduced to account for the observed kinetic data.

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Kinetic Modelling of the Adsorption of Methylene Blue onto Blue Green Algae

Renugadevi N. and Krishnaveni J. *

The present paper deals with the kinetics of the adsorption of Methylene Blue dye from the aqueous solution using dried Blue Green Algae as an adsorbent. The rate constants for the adsorption of Methylene Blue dye were determined using Lagergren rate equation, Intraparticle diffusion rate equation and Elovich rate equation.

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Swelling Behavior of Carboxymethyl cellulose-g-PMAAm-co-PNIPAm Superabsorbent Hydrogels

Sadeghi Mohammad* and Soleimani Fatemeh

A novel superabsorbent hydrogel was synthesized via crosslinking graft copolymerization of N-isopropylacrylamide (NIPAAm) and methacrylamide (MAAm) onto Carboxymethyl cellulose (CMC) backbones in a homogeneous solution. The methylenebisacrylamide (MBA) and amounium persulfate (APS) were used as water-soluble crosslinker and initiator respectively. Evidence of grafting was obtained by comparing FTIR, SEM spectra of CMC and the graft copolymer as well as solubility characteristics of the products. A mechanism for the superabsorbent hydrogel formation was also suggested. The effect of MBA, APS, CMC concentration and MAAm/NIPAAm weight ratio on the water absorbency capacity has been investigated. The swelling variations of hydrogels were explained according to swelling theory based on the hydrogel chemical structure. The temperature-sensitivity properties of the hydrogels also make the intelligent polymers as good candidates for considering as potential carriers for bioactive agents e.g. drugs.

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Synthesis and Characterization of Ruthenium(II) Complexes of N-Carboethoxy-4-halobenzene Thioamide Ligands

Misra Sunil K.* and Tewari Rajesh C.

Aromatic thioamides, ArCSNHCOR are quite versatile in their ligating behaviour and provide a variety of coordination modes with transition metal ions and their complexes for substitution reactions. In our earlier published work we have reported the coordination modes of N-carboethoxy-4- chlorobenz¬ene- and N-carboethoxy-4-bromobenzene thioamide ligands (Hcct and Hcbt) with bivalent, trivalent and tetravalent transition metal ions; reactions of these ligands with metal salts in presence of pyridine; with [Cu(EPh3)3X] (E = P or As; X = Cl, Br or I) and characterisation of some novel complexes of RhI, Pd0 and Pt0 through substitution reactions. In the present study, we report the synthesis of Ru(II) complexes through the reactions of [RuCl2(PPh3)], [RuCl2(CO)2] and [(η5-C5H5)RuCl (AsPh3)2] with the ligands Hcct and Hcbt (HL). The structural aspects of the resultant ruthenium complexes [RuCl2-(HL)2 (PPh3)], [RuCl2(CO)2(HL)] and [(η5-C5H5) RuCl (HL)(AsPh3)] have been discussed on the basis of analytical, infra red, electronic spectral and magnetic measurements.

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ab initio, NBO and NICS Studies of the Decomposition (2+2 elimination) Mechanisms of 2-Halo-2, 3-dihydropyridines

Jameh-Bozorghi Saeed1*, Ghaempanah Aram2, Rad Vahid2 and Esfandyari Hadi 2

The decomposition of 2-Fluoro-2,3-Dihydropyridine (1) 2-Chloro-2,3-Dihydropyridine(3) 2-Bromo-2,3-Dihydropyridine(5) to pyridine and HX(X=F, Cl, Br) was investigated using AB initio Molecular Orbital (MO) and Density Functional Theory (DFT). This is possible for all HX elimination reactions examined here, two pass ways as well as three or four centered transition state structures. Calculation results for the B3LYP/6-311+G**, HF/6-311+G**// B3LYP /6-311+G** and MP2/6-311+G**// B3LYP /6-311+G** levels of theory for comparison of these two pass ways showed that passing from four centered-transition state is more likely than three centered-transition state. Study on the B3LYP/6-311+G** level of theory revealed that the required energy for decomposition of compound 1, 3 and 5 to pyridine is 32.483165, 23.329822 and 19.987130 kcal mol−1 respectively. In a similar vein, these calculations were performed on HF/6-311+G**// B3LYP /6-311+G** and MP2/6-311+G**// B3LYP/6-311+G** levels of theory. Nat-ural Bond Orbitals (NBO) population analysis and Nuclear Independent Chemical Shift (NICS) results showed that in transition state (four-membered planar structure) C-H and C-X bonds break and H-X bonds appear; besides, the results showed that reactants are non-aromatic, but elimination reaction products are aromatic.

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Application of atomic force microscopy in ion exchange membrane technology

Han Chunjie

AFM is the main tool in the area of the current scientific development. It has many merits that other microscopes have no way to compare. This paper focuses on the use of atomic force microscopy in testing of ion exchange membrane. The analysis about exchange membrane has been carried on under each kind of situation to obtain superficial appearance image and other important parameters such as roughness about different-phase polyethylene ion exchange membrane. These parameters have played a very important role on the research of membrane and provide reliable scientific data for further studies on membrane.

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Inhibition reaction for 1, 1, -di-tert-butylperoxy-3,3,5-trimethylcyclohexane mixed with monoammonium phosphate by DSC

Chen Jin-Luh1, Lin Jian-Zhi2, Lin Chun–Ping3, Su Chung-Hwei4, Lin Yan-Fu5, Yang Wein-Duo1 and Tseng Jo-Ming2*

Organic peroxides are common petrochemical raw materials that are very unstable. Several severe fires and explosions have been induced in East Asia during the last four decades, causing casualties and property losses. The most important way to lessen the hazard is by using the effectiveness of the extinguishing agent when a fire occurs. 1,1,-di-tert-butylperoxy-3,3,5-trimethylcyclohexane (TMCH) 88 mass% was employed and then the extinguishing agent of monoammonium phosphate (MAP) was added. Differential scanning calorimetry (DSC) was applied with the curve fitting method to identify the root cause of runaway reactions. Finally, results indicated that MAP apparently had an endothermic peak after the first exothermic peak because the free radical chain reaction was inhibited. Results could be applied to improve MAP for achieving process safety.

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Treatment of aged-landfill-leachate using aged-sludge-based bioreactor followed by advanced chemical oxidation

Shi X. L.,1* Wei Y. M.2,3 and Liu Y. D.1

Sludge in the landfills and dumping sites becomes stabilized or aged during its long-term stabilization process. The aged sludge contains a wide spectrum and large quantity of microorganisms which can effectively decompose refractory organic matter present in some wastewaters, such as Municipal Solid Waste (MSW) landfill leachate. In this work, four biofiltration reactors consisted of the aged sewage sludge taken from a 5-year sludge lysimeter used for biofiltration of aged MSW landfill leachate sampled from a closed landfill. The removal of the total nitrogen was quite low, only around 20-60%. The NH4+-N is mainly converted to nitrate-N. The removal of the total P is high, possibly because of the strong absorption capability of the aged sludge in the bioreactor used. The effluent looks clear in comparison with the brownish color of the influent and can be chemically oxidized further to the value of current discharge standards of China. The treatment process developed is simple and easily operated.

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Chemical Screening of Root Bark of Zizyphus Joazeiro Mart Plant from Rhamnaceae Family

Pandey A.K. and Singh Shweta*

The purpose of this study was to extract and investi-gate the root bark of the plant Zizyphus joazeiro for the presence of Cyclopeptide alkaloids and flavonoids. Chromatographic resolution of the benzene methanol-ammonium hydroxide extract of the root bark of Zizyphus joazeiro Mart (Family: Rhamnaceae) resulted in the isolation of the three cyclopeptide alkaloids designated as Zj-1, Zj-2 and Zj-3 and one flavonoid designated as Zj-4. The Zj-1, C33H43N5O4 (M+, m/z 573.3324), m. p. 235-380C; Zj-3, C31H42N4O4 (M+534.3174) m. p. 263-650 and Zj-4, C6H12O6 (M+, m/z 300) were characterized as nummularine-K (I), nummularine-M (II) and kaempferol-7-methyl ether (III) respectively. Finally the correctness of the structures (I), (II) and (III) was verified from direct comparison, co-TLC, TLC, M. P. M.M.P. and superimposable IR. The alkaloid Zj-2, colorless granules m. p. 216-180C [α] 20D- 1350 (c, 0.18, CHCl3), was recog-nized as the 13membered ring cyclopeptide alkaloid as indicated by its UV spec-trum.13CNMR of Zj-2 was comparable with that of paliurine-E (IV). The difference between two was observed with the chemical shift of carbon signals due to the attachment of ring bound and terminal amino acids. 13C NMR signals favored phenyla-lanine as ring bound to styrylamine function and N-mono-methylphnylalanine as terminal amino acid in Zj-2. A scrutiny of IR, UV, 1H NMR, 13C NMR, hydrolysis, partial hydrolysis experiments and high resolution mass spectrometric analysis revealed that Zj-2 has gross structural similarity with that of nummularine-S (V) with only difference in having N-monomethylph-nylalnine instead of leucine as terminal amino acid. The structure of Zj-2 was settled as (VI), which is a new 13-membered ring cyclopeptide alkaloid, designated as joazeirine.

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Adsorption of Basic Red 46 onto Activated Carbon

Dao Sy Duc1*, Nguyen Van Noi1, Do Quang Trung1, Vu Thi Quyen1 and Vu The Ninh2

In this work, activated carbon was used to remove Basic Red 46 (BR 46) from aqueous solution. Several characteristics of materials were characterized by BET, XRD, SEM. Effects of some key operating parameters such as pH, adsorbate dose and contact time on the dye removal were investigated and discussed. The experimental results show that activated carbon is a promising adsorbent for removing BR 46. Under the suitable conditions, the dye removal is approximately 100%. Equilibrium data fitted well with the Langmuir isotherm model. The monolayer sorption capacity was found as 714.28 mg/g. Kinetic data were best described by the pseudo-first order model with kinetic rate constant is 12.667 x 10-3 min-1.

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Kinetics and Thermodynamics of Cr Ions Sorption on Mixed Sorbents prepared from Olive Stone and Date pit from Aqueous Solution

Aksas H*., Boureghda M. Z., Babaci H. and Louhab K.

In this research, adsorption of chromium onto the mixture of olive stone and date pit has been studied through using batch adsorption techniques. The main objectives of this study are to investigate the chromium adsorption from aqueous solution by mixture of olive stone and date pit and to study the influence of contact time, pH and initial chromium concentration on adsorption process performance and to determine appropriate adsorption isotherm and kinetics parameters of chromium adsorption. The results of this study showed that adsorption of chromium by mixture of olive stones and date pit reached to equilibrium after 120 min and after that a little change of chromium removal efficiency was observed. Medium chromium adsorption was observed at lower pH and maximum chromium removal 53.42 mg/g for (88% DP, 12% OS) obtained at pH of 5. The obtained results showed that the adsorption of chromium by mixture of olive stone and date pit follows Langmuir isotherm equation with a correlation coefficient equal to 0,9988 for (88% DP, 12% OS). In addition, the kinetics of the adsorption process follows the pseudo second-order kinetics model. The results indicate that the mixture of olive stone and date pit can be employed as a low cost alternative to commercial adsorbents in the removal of chromium from water and wastewater.

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Metals in Kitagata Hot Springs and Water Quality Effect from Balneotherapy and Hydrotherapy

Aluoch June* and Sillanpää Mika

Following the popularity of Kitagata hot spring spa therapy and limited scientific studies, the use and cation-content of the hot spring water in Kitagata Uganda was therefore investigated. The hotspring was divided into four zones according to use by tourists as well as the local community which includes; drinking, balneotherapy, hydrotherapy and outflowing water. Samples were taken from each zone and cations were analysed in the samples through Inductively Coupled Plasma – Optical Emission Spectrometry (ICP-OES). Labile parameters such as pH, temperature and electrical conductivity (EC) were measured in-situ. Na, K, Mg, Ca, S, P, Mn, Li, Fe and Al were detected and compared against WHO drinking water guidelines14. The results implied no WHO exceeded values in cation content. Fe levels which were not detected from the source of the hot spring water were detected in the ouflowing water which also implied that Fe levels may have increased due to hot-spring use.

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Porosity Development in Activated Carbon from Palm Kernel and Coconut Shell by Chemical Activation Method

Rahman M. M.,1* Mohammad Adil2 and Yusof A. M. 2

Several series of activated carbons have been prepared by chemical activation with phosphoric acid from palm kernel and coconut shells to study the effect of preparation variables such as precursor, precursor size, pretreatment, impregnation condition and ratio and finally the carbonization temperature on specific surface area and pore distribution of the resulting active carbon. Both precursors showed similar N2 adsorption isotherms, an upward deviation at high relative pressure, revealing the presence of mesorpores when carbonized at 5000 C with H3PO4. The bigger hysteresis loop indicates higher mesoporosity in coconut shell derived carbon whereas palm kernel shell derived carbon showed a higher macroporosity nature. Prolong sinking of the precursor in H3PO4 impregnation solution followed by carbonization at moderate temperature (450-5000 C) produces carbon of high surface area with a higher macroporosity. The lowering of precursor size favors micropore development and semi-drying of the impregnation chemical prior to carbonization diminishes the macroporosity to a great extent. Thus an appropriate choice of preparation variables enables us to produce high surface area of micro and mesoporous activated carbon.

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Sonochemical degradation of volatile and Non-volatile compounds

Goel Mukesh 1, Das Ashutosh 1, Ravikumar K.1*and Nagarajan R. 2

Destructive technologies for the wastewater treatment have significant benefits. The advanced oxidation processes (AOP) promises much in this regard. The AOP generate free radicals which act as strong oxidant to destroy the organic pollutants. AOP includes several methods such as: H2O2/UV, O3/UV and UV/TiO2. Among the above, ultrasonication is one of the less studied methods despite its unique and extreme conditions generated without using complicated and unsafe process. Ultrasonication promotes oxidative degradation of the target compound by hydroxyl radicals and also provides a possible route for thermal decomposition in the gas phase. The combination of ultrasonication and other AOP like photoxidation and ozonation substantially increases the decomposition rate of organic pollutants by increasing the amount of hydroxyl radicals required to oxidize the pollutants. The objective of this paper is to critically review the efficacy of sonolysis and its combination with other AOP on the destruction of undesirable compounds in aqueous solutions.

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Microbial Remediation of Polycyclic Aromatic Hydrocarbons: An Overview

Khobragade Vaidehi * and Kulkarni S. D.

Present day poses immense threat by extensive environmental pollution caused due to inorganic and organic chemicals. This necessitates novel methods of decontamination and cleanup.The polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in distribution and have lethal effects on human health. Further, contamination of soils and aquifers by PAHs is of great environmental concern. Considering the relative high cost and non-specificity of conventional techniques, microbial remediation has emerged as an alternative technology with great potential for pollutant clean-up. This technology is very effective, particularly in dealing with petroleum hydrocarbon contamination. Given the ability of some microorga-nisms in transforming and degrading PAHs, they may be used in removal of PAHs from the environment. Fungi and bacteria in a consortium bring about more effective degradation. The major aerobic and anaer-obic pathways of breakdown of PAHs are discussed in this review. The successful use of microbial popu-lation for remediation of PAH-contaminated sites requires a deeper understanding of microbial PAH degradation. With this goal the present review provides a broad outline of the development of biore-mediation techniques and strategies, factors affecting bioremediation, microbial populations involved in degradation. It encompasses information on the biological processes and ways to enhance the biore-mediation process for quick and effective removal of the PAH-contaminants.

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