J. Chil. Chem. Soc., 54, Nº 3 (2009)

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JOURNAL OF THE CHILEANCHEMICAL SOCIETY

VOL. 54 Nº 3

Director : Dr. Patricio Reyes Nuñez (Facultad de Ciencias Químicas, Universidad de Concepción)

Editor : Dr. Carlos Díaz Valenzuela (Facultad de Ciencias, Universidad de Chile)

Legal Representative : Dr. Patricio Reyes Nuñez (Facultad de Ciencias Químicas, Universidad de Concepción)

Exchange Section : Dra. Fresia Orellana Alvarez (Facultad de Ciencias, Universidad del Bío Bío)

Intelectual Property : Sociedad Chilena de Química, Legal Resolution Nº 5.909 December 12, 1946. RUT 70.225.000-5 Address: Paicaví 170, Depto. 19, Phone 41- 2227815, Fax 41- 2235819, Concepción. P.O. Box. 2613, Concepción, Chile www.schq.cl

This publication is partially supported by “Convenio del Financiamiento de Publicación de Revistas Científicas”, CONICYT (Chile).

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SIMULTANESOUS SPECTROPHOTOMETRIC DETERMINATION OF NORFLOXACIN, OLFOXACIN AND LOMEFLOXACIN IN RABBIT BLOOD SERUM BY USE OF CHEMOMETRICS

XI-GEN HUANG*, HENG-SONG ZHANG, YAN-XIA LI, MING-FANG LI

Department of Chemistry, Jiangxi Agricultural University, Nanchang 330045, P. R. China

A spectrophotometric method for simultaneous determination of norfloxacin, ofloxa-cin and lomefloxacin by classical least square, principal component regression, par-tial least squares, and radial basis function-artificial neural network is described.

THE INHIBITION MILD STEEL CORROSION IN PHOSPHORIC ACID SOLUTIONS BY 2- PHENYL-1-HYDRAZINE CARBOXAMIDE

A.DADGARINEZHAD*, F.BAGHAEI

Materials Engineering Department ,ShahiD Bahonar University ,Kerman ,Iran

In this work the effect of 2-phenyl-1-hydrazine carboxamide on the corrosion of mild steel in solutions of phosphoric acid (H3PO4) has been investigated in relation to the concentration of the inhibitor and acid, by weight loss, poten-tiodynamic polarization, and AC impedance (EIS) measurements. Results obtained revealed that this compound is a good mixed –type inhibitor. The surface morphologies of specimens after 1 hour of immersion in various solutions were studied by scanning electron microscopy (SEM).

INFLUENCE OF ENVIRONMENTAL FACTORS IN THE ATMOSPHERIC CORROSION OF COPPER IN THE PRESENCE OF PROPIONIC ACID

A. ECHAVARRÍA, F. ECHEVERRÍA*, H. GIL AND C. ARROYAVE

Corrosion and Protection Group, University of Antioquia, Carrera 53 # 61 – 30, Medellin, Colombia

Exposure time, pollutant concentration, and relative humidity (RH) are important environ-mental variables for the atmospheric corrosion of copper in the presence of propionic acid vapors. This paper shows the most outstanding results into the effect of these variables. This study was carried out by mean of exposures at dynamic conditions in 260, 380, and 680 ppbv propionic acid, with relative humidities of 70% and 90%. The effect of the propionic acid was also evaluated in static conditions with 4, 40, and 120 ppmv propionic acid with relative hu-midities of 40%, 80%, and 100% RH. All the samples were evaluated by triplicate within 21

IDENTIFICATION OF TRITERPENES AND STEROLS FROM PTEROGYNE NITENS (FABACEAE) USING HIGH-RESOLUTION GAS CHROMATOGRAPHY

LUIS O. REGASINI, GERARDO M. VIEIRA-JÚNIOR, DANIARA C. FERNANDES, VANDERLAN S. BOLZANI, ALBERTO J. CAVALHEIRO, DULCE H. S. SILVA*

NuBBE – Institute of Chemistry, São Paulo State University, Araraquara, SP, Brazil, CEP 14801-970

As part of our ongoing bioprospecting studies on secondary metabolites in plants of Cerrado and Atlantic Rain Forest of São Paulo State (Brazil), we describe the identification of triterpenes and sterols present in the hexane extracts and foliar epicuticular wax of Pterogyne nitens by HR-GC. The method reported herein is shown to be a rapid, sensitive and reproducible tool for describing triterpenes and sterols present in non-polar extracts.

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INFLUENCE OF SOME INTERCALATIONS ON ACTIVATION OF PRE-BAKED CLAY

IMTIAZ AHMAD a, * HAMEED ULLAH a, b

a Institute of Chemical Sciences, University of Peshawar, 25120, N.W.F.P, Pakistan

bInstituto de Química, Universidade Estadual de Campinas, 13083-970, Campinas, Sao Paulo, Brazil.

In this paper we report on the influence of temperature, mixing ratio and holding time of NaOH & KOH intercalations on the surface area, micropore volume and micropore width of pre-baked clay samples. The effects of the intercalation were studied using pore size and surface area analysis, XRD, EDX and SEM analysis. A meaning full effect was observed when the temperature was increased from ambient up to 150 oC in case of both intercalating agents. Increasing temperature beyond 150 oC caused a decline in surface area generation even up to 750 oC. The results also show that mixing ratio has a positive effect on the porosity and the micropore surface area. The influence of holding time shows two different trends. In case of NaOH, the porosity increases as the time increases while in case of KOH, the porosity decreases as the time increases. The results show effective insertion of the sodium and potassium into the clay matrix thereby causing generation of porosity.

SIMULTANEOUS QUANTITATION OF OLMESARTAN MEDOXIMIL AND AMLODIPINE BESYLATE IN COMBINED TABLETS USING HPLC

SYED SHANAZ QUTABA, SYED NAEEM RAZZAQA, , MUHAMMAD ASHFAQB, ISLAM ULLAH KHANB, AHMAD MAHMOOD MUMTAZC

aSchazoo Laboratories (Pvt) Ltd. 45. G.T. Road, Lahore-54000, PakistanbDepartment of Chemistry, Government College University, Lahore-54000, PakistancUniversity College of Pharmacy, University of the Punjab, Lahore-54000, Pakistan

A simple, sensitive and isocratic reverse phase high performance liquid chromatographic (RP-HPLC) method has been developed for the simultaneous determination of olmesartan medoximil and amlodipine in pharmaceutical tablet formulations. HPLC analysis was carried out using reverse phase isocratic elution with a C18 column and a mobile phase of 0.05 M ammonium acetate pH 6.8 and acetonitrile in the ratio of 40:60, v/v. Detection of the analytes was achieved using UV detector at 239 nm.

SYNTHESIS, CHARACTERIZATION, THERMAL PROPERTIES AND ANTIMICROBIAL ACTIVITY OF ACRYLIC COPOLY-MERS DERIVED FROM 2,4-DICHLOROPHENYL ACRYLATE

ANKIT K. PATEL, RAJESH J. PATEL, KIRIT H. PATEL AND RAJNI M. PA-TEL†

Department of Chemistry, Sardar Patel University, Vallabh Vidyanagar-388120, Gujarat, India.

The monomer 2,4-DCPA was synthesized, characterized and copolymerized with MMA using different feed ratio by solution polymerization. The resulting copolymers were characterized by conventional techniques. The results of reactivity ratio indicate the r¬¬1 grater then r2 and the value of r¬¬1 and r2 less then one, so the system gives rise to azeotropic polymerization at a particular composition of the monomer. The number average molecular weight was in range of 5382 to7923 g/mol. The VPO results show that the incorporation of 2,4-DCPA with MMA increases the overall monomer weight of the copolymers. Thermal analysis showed that all copolymers of 2,4-DCPA undergo single step decomposition and homo polymers decomposition in a double step. The chlorine content of the polymers appears to be the most important component to enhance antimicrobial activity. It is hoped that such chlorine containing copolymers will find use as antimicrobial agents.

COMPARISON BETWEEN UV SPECTROPHOTOMETRY AND ANION EXCHANGE CHROMATOGRAPHY TECHNIQUES FOR QUANTIFICATION OF HEXENURONIC ACID (HEXA) IN UNBLEACHED KRAFT PULPS OF EUCALYPTUS GLOBULUS

MARIEL MONRROY,1,2 LORETO SANHUEZA,1 REGIS TEIXEIRA MENDONÇA,1,2 JAIME BAEZA1,3 AND JUANITA FREER1,3

1Renewable Resources Laboratory, Biotechnology Center, 2Faculty of Forestry Sciences, 3Faculty of Chemical Sciences. Universidad de Concepción, Casilla 160-C, Concepción, Chile.

Two different acid hydrolysis methodologies were optimized for hexenuronic acid (HexA) degradation in E. globulus kraft pulps. Products generated were quantified by UV spectrophotometry or anion exchange chromatography (AEC).

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THE BALL MILLING EFFECT ON TRIBASIC CALCIUM PHOSPHATE AND ITS CHROMIUM (VI) ION SORPTION PROPER-TIES

F. GRANADOS-CORREA, J. BONIFACIO-MARTÍNEZ, J. SERRANO-GÓMEZ

Instituto Nacional de Investigaciones Nucleares, Departamento deQuímica, A. P. 18-1027, Col. Escandón, Delegación Miguel Hidalgo, C.P. 11801 México D.F., México.

Ball milling of TCP samples reduced the pores of TCP particles and, consequently, the specific area of milled samples. The unexpected increase in Cr(VI) sorption can be explained by presence of Fe atoms (detected by XRD) in milled TCP samples.

Fig. 2. SEM images of the calcium phosphate tribasic sam-ples: a) CPT, b) TCP-5, c) TCP-10, d) TCP-15.

INFLUENCE OF BATH TEMPERATURE AND pH VALUE ON PROPERTIES OF CHEMICALLY DEPOSITED Cu4SnS4 THIN FILMS

ANUAR KASSIM1, TAN WEE TEE1, ATAN MOHD. SHARIF1, DZULKEFLY KUANG ABDULLAH1, MD. JELAS HARON1, HO SOON MIN1AND NAGALINGAM SARAVANAN2

1Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.2Department of Bioscience and Chemistry, Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, 53300 Kuala Lumpur, Malaysia.

a very brief summary of the main results of the work

The films deposited at 50 °C were found to have the best photoresponse activity and smaller crystal size. At pH 1.5, the film showed well-covered entire substrate surface and the highest absorption values in AFM and optical study, respectively.

OLIGOMER CHAIN LENGTH EFFECT ON THE NUCLEATION AND GROWTH MECHANISM (NGM) OF POLYTHIPHENE

M. ANGÉLICA DEL VALLE1, MANUEL A. GACITÚA*1, LUIS I. CANALES1 AND FERNANDO R. DÍAZ1

1Pontificia Universidad Católica de Chile. Facultad de Química, Departamento de Química Inorgánica, Laboratorio de Electroquímica de Polímeros. Av. Vicuña Mackenna 4680, 7820436 Macul, Santiago, Chile. magacitu@uc.cl

A comparative study of the starting unit chain length effect on the polythiophene (PTh) electrosynthesis. The obtained NGM allows stating that the growth of PTh from each of the starting units have the same predominant contribution, diffusional 3D instantaneous nucleation, and the others disappear as the unit length increase. This validates the previously reported electropolymerization model according to:

STUDY OF THE ZEOLITIZATION PROCESS OF FLY ASH USING AN ORTHOGONAL ARRAY OF TAGUCHI EXPERIMENTAL DESIGN.

A. MEDINA R*., P. GAMERO M., J. M. ALMANZA R., D. A. CORTÉS H. AND G. VARGAS G.

Centro de Investigación y Estudios Avanzados del IPN. Unidad Saltillo.Carretera Saltillo-Mty Km. 13.5 Ramos Arizpe, Coah. Mex. C.P. 25900 A.P. 663.

Zeolitization of fly-ash by a directed route and a fusion method was studied using an orthogonal array of Taguchi experimental design. The statistical significant processing conditions that show a stronger effect on the zeolite content were the type of mineralizing agent and crystallizing temperature. When using the direct method potassium hydroxide (KOH) was the optimal mineralizing agent and when using the fusion method the optimal alkaline agent was sodium hydroxide (NaOH).

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FACILE SYNTHESIS OF ISOXAZOLES AND PYRAZOLES FROM β-DIKETOHYDRAZONES

CARLOS BUSTOS1, EDUARDO SCHOTT3, MARCELA RÍOS1, CHRISTIAN SÁNCHEZ1 AND JUAN-GUILLERMO CÁRCAMO2

1Instituto de Química, Universidad Austral de Chile, Avda. los Robles s/n, Casilla 567, Valdivia, Chile.2Instituto de Bioquímica, Universidad Austral de Chile, Avda. Casilla 567, Valdivia, Chile.3Departamento de Ciencias Químicas, Universidad Andrés Bello, República 275, Santiago de Chile, Chile.

This work report the syntheses of series of 3,5-dimethyl-4-[(E)-4-(R1-phenyl)diazenyl]isoxazoles (I) and 3,5-dimethyl-1-(R2-phenyl)-4-[(E)-(R1-phenyl)diazenyl]-1H-pyrazoles (II). All compounds may be obtained, in acid medium using ethanol as solvent, by reaction of 3-[2-(R1-phenyl)hydrazono)]pentane-2,4-dione with H2NOH·HCl and R2-4-C6H4-NHNH2, respectively.

SYNTHESIS, CHARACTERIZATION OF A NEW CARBONYLATED ZIRCONIUM METALLOCENE USING A DICHLORO-ZIRCONOCENE DERIVED FROM PARTIALLY ALKYLATED S-INDACENE

J.F.ARANEDAa, S.SALINASa, D. MAC-LEOD-CAREYa, A. MUÑOZ-CASTROb, R. ARRATIA-PEREZb, C.ADAMSa, I.CHÁVEZa, J.M.MANRÍQUEZA,*

aDepartamento de Química Inorgánica, Facultad de Química, Pontificia Universidad Católica de Chile. Casilla 306 Correo 22, Santiago, Chile. e-mail: jmanriqm@uc.cl bFacultad de Ecología y Recursos naturales, Universidad Andres Bello, Republica 275, Santiago, Chile

Synthesis, characterization and theoretical calculations of a new organometallic mononuclear zirconium complex with a s-indacene ligand, and its respective dicarbonyl complex obtained by reduction with Mg/HgCl2 are presented.

ORGANOCHLORINE INSECTICIDES (DDT AND HEPTACHLOR) IN DRY FISH AVAILABLE IN BANGLADESH: SEASONAL TRENDS AND SPECIES VARIABILITY

MD. NURUL HUDA BHUIYAN1*, HABIBUR RAHMAN BHUIYAN1, K. K. NATH1, KABIR AHMED1, MD. TARIQUL HASSAN2 AND MD. NAZRUL ISLAM BHUIYAN1

1BCSIR Laboratories Chittagong, Chittagong-4220, Bangladesh, 2IFST, BCSIR, Dhaka, Bangladesh.

The concentrations of organochlorine insecticides DDT and Heptachlor were investigated to estimate the current status of insecticides used in dry fish in different season and different species. Six most popular species of dry fishes namely Bombay duck (Loittya), Ribbon fish (Chhuri), Shrimp (Chingri), Hilsha shed (Ilish), Chinese pomfret (Rupchanda) and Indian salmon (Lakhua) were collected from Asadgonj (whole sell market for dry fish) of Chittagong, Bangladesh at different seasons, six samples at winter season (December) and six same samples at rainy season (July). The range of DDT concentration at winter was found 3.6 ug kg-1 to 250.8 ug kg-1 and at rainy season the range of concentration was found 11.1 ug kg-1 to 1107.4 ug kg-1. The range of Heptachlor concentration at winter was found 0.4 ug kg-1 to 2.5 ug kg-1 and at rainy season was found 1.1 ug kg-1 to 37.8 ug kg-1. The concentrations of DDT and Heptachlor were much higher in the samples of rainy season than the same samples of the winter.

A FLUORESCENCE QUENCHING METHOD FOR DETERMINATION OF COPPER IONS WITH CDTE QUANTUM DOTS

YILIN WANG, JIANPING LU, ZHANGFA TONG, HAIFENG HUANG

College of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, PR ChinaCorresponding author: Yilin Wang,

CdTe QDs capped with L-cysteine were synthesized in aqueous solution, and a novel method for the determination of Cu2+ was developed based on its fluorescente quenching for the Qds. Under the optimum conditions, calibration curve was linear in the range of 20-300ug.L-1 with the correlation coefficient of 0.998, the detection limit of Cu2+ was -.3yg.L-1. Furthermore, the feasibility has been proven by the determination of trace copper in hair and tea samples with satisfactory results.

Fluorescence spectra of CdTe QDs in the presence of Cu2+

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OPTIMIZATION AND EFFECTS OF SOME ELECTRON ACCEPTORS ON THE PHOTOCATALYTIC DEGRADATION OF DIRECT RED 23 AZO DYE

DÉBORA N. CLAUSEN, IEDA S. SCARMÍNIO, AND KEIKO TAKASHIMA*

Department of Chemistry, Universidade Estadual de Londrina, 86051-990, Londrina, Paraná, Brazil.

The photocatalytic degradation of direct red 23 was carried out in TiO2 suspension at 30ºC. Seven chemical species were determined during the azo dye degradation through Imbrie Q mode factor analysis followed by varimax and Imbrie oblique rotations.

MOLECULAR RECOGNITION OF SULFAQUINOXALINE AND SULFAPYRIDINE WITH MOLECULARLY IMPRINTED POLYMER

T.C. CHENGa, Y.T. HUANGb , C.Y.CHANGa, K.S.YAOa, C.C. HWANG a*

aDepartment of Life Science,Mingdao University, Peetow, ChangHua, 52345, TaiwanbInstitute of Bioinformatics and Structural Biology,National Tsing Hua University, Hsinchu, Taiwan

The selective separation of sulfapyridine (SPD) from sulfaquinoxaline (SQX) is investigated by applying high performance liquid chromatography (HPLC) with molecularly imprinted polymer (MIP) as the stationary phase. Our results are discussed with regard to the composition of the chromatographic mobile phase and adsorption capacity.

Figure Binding amounts of SPD and SQX to the imprinted particles. These particles prepared at 4 ℃, 65 ℃ and used SPD as template.

PREPARATION AND CHARACTERISTICS OF NOVEL HYPERBRANCHED PEU-BASED GEL POLYMER ELECTROLYTES

CHUAN WU *, FENG WU, YING BAI , TING FENG , CHUNHUA PAN , LIN YE , ZENGGUO FENG

5# South Zhongguancun Street, Haidian district, Beijing 100081, China

Gel polymer electrolytes (GPEs) based on hyperbranched poly (ether urethane) (PHEU) were prepared from the reaction of the hyperbranched polyether (PHEMO) with different diisocyanates in liquid electrolyte. The ionic conductivities and transference number of the GPEs were investigated by alternating current (AC) impedance and multi-potential steps. It is found that the ionic conductivities of GPEs were influenced by diisocyanate structure, lithium salt concentration and addition amount of liquid electrolyte. Sample PUM-0.5M-80% originated from 4, 4-diphenylmethane diisocyanate (MDI) as the hard segment shows the highest ionic conductivity of 2.41×10-3 S•cm-1 at ambient temperature. The lithium ion transference number is 0.7. In addition, small molecules of liquid electrolyte were perfectly enclosed by polymer matrix, which can avoid liquid leaking in lithium ion battery.

TRACE ELEMENTS AND OPERATIONAL SPECIATION OF ANTIMONY, ARSENIC, COPPER, IRON, MANGANESE AND ZINC IN SOILS OF TWO HIGH-ANDEAN SALARS OF NORTHERN CHILE

VENECIA HERRERA* 1, IDA DE GREGORI 2, HUGO PINOCHET 2

Laboratorio Química Analítica y Ambiental. Departamento de Ciencias Químicas y Farmacéuticas. Universidad Arturo Prat. Avenida Arturo Prat 2150. Iquique, Chilevenecia.herrera@unap.cl; fax 57 394 365Laboratorio Química Analítica y Ambiental, Instituto de Química; Facultad de Ciencias Básicas y Matemáticas. Pontificia Universidad Católica de Valparaíso, Avenida Brasil 2120, Valparaíso, Chile

Speciation of Sb, As (contaminated), Cu, Fe, Mg and Zn determinated in the soils from the salars of Huasco and Coposa of the northern Chilean Altiplano. Arsenic can be found more mobile in alkaline soil and have availability in neutral soil of Coposa.

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SPECTROPHOTOMETRIC AND RP – HPLC DETERMINATION OF NITAZOXANIDE AND OFLOXACIN IN TABLET DOSAGE FORM

SANTOSH GANDHI*a, VIJAY JADHAV a, NILESH DHAVALEa, KAILASH BOTHARAa

aDepartment of Pharmaceutical Analysis,A.I.S.S.M.S. College of Pharmacy, Kennedy Road, Near R.T.O., Pune- 411 001 (INDIA)

Spectrophotometric (dual wavelength method) and RP-HPLC (on HiQ-SiL C18 column using ACN: 0.005 M TAHS, 55: 45 v/v as mobile phase) determination of Nitazoxanide and Ofloxacin in combined tablet dosage form has been developed.

DIRECT ORTHOGONAL SIGNAL CORRECTION-PARTIAL LEAST SQUARES FOR SIMULTANEOUS SPECTROPHOTOMETRIC DETERMINATION OF SULFAMETHOXAZOLE AND TRIMETHOPRIM IN PHARMACEUTICAL FORMULATION AND SYNTHETIC SAMPLES

MOHAMMAD GOODARZI 1,2,* PARVIZ SHAHBAZIKHAH 3, MAHMOUD REZA SOHRABI4, MOZHGAN FATHABADI 4, AREZOO HASSAN NOURI 4

1 Department of Chemistry, Faculty of Science, Azad University of Arak, Arak, Iran2 Young Researches Club, Azad University, Arak, Iran3 Department of Chemistry, Sharif University of Technology, Tehran, Iran4 Department of chemistry, Azad University-North Tehran Branch, Tehran, Iran

This work describes a very simple, novel and selective spectrophotmetric method for simultaneous determination of sulfamethoxazole and trimethoprim in pharmaceutical preparation and synthetics samples using direct orthogonal signal correction-partial least squares (DOSC-PLS). The all factors affecting on the sensitivity were optimized and the linear dynamic range for determining of these drugs was found. The PLS modeling was used for the multivariate calibration of the spectrophotometric data and DOSC was used for preprocessing of data matrices and the prediction results of model. The experimental calibration matrix was designed by measuring the absorbance over the range 200–400 nm for 32 samples of 2.0–15.0 and 0.4-6.0 μg mL-1 of sulfamethoxazole and trimethoprim, respectively. The root mean square error of prediction for sulfamethoxazole and trimethoprim using DOSC-PLS and PLS were 0.02212, 0.02363 and 0.17014, 0.01660,μg mL-1 respectively. Application of the method to synthetic samples of standard solutions and in pharmaceutical formulation was performed and satisfactory results were obtained.

N-METHYL-1H-INDOLE-2-CARBOXAMIDE FROM THE MARINE FUNGUS CLADOSPORIUM CLADOSPORIOIDES V. MANRÍQUEZa, A. GALDÁMEZa, B. VELIZA, J. ROVIROSAa, A. R. DÍAZ-MARREROb, M. CUETOb J. DARIASb, C. MARTÍNEZc AND A. SAN-MARTÍNA.

aDepartamento de Química, Facultad de Ciencias, Universidad de Chile. Casilla 653, Santiago, Chile.bInstituto de Productos Naturales y Agrobiología del CSIC, ZIP Code 38206, La Laguna, Tenerife, EspañacUniversidad de Santiago de Chile. Santiago. Chile

The crystal structure of N-methyl-1H-indole-2-carboxamide C10H10N2O, was determined by single crystal X-ray diffraction. The 1H and 13C-NMR spectra are discussed and related to the crystal structure.

BLENDS OF POLY(VINYL PYRIDINE)S AND TWO DIHYDRIC PHENOLS: THERMAL AND INFRARED SPECTROSCOPIC STUDIES. PART II.

NICOLÁS GATICA* AND NANCY ALVARADO

Departamento de Polímeros, Facultad de Ciencias Químicas, Universidad de Concepción, Casilla 160-C, Concepción, Chile. *E-mail: nigatica@udec.cl, fax: 56-41-2245974.

The miscibility in blends containing poly(4-vinyl pyridine) (P4VPy) and poly(2-vinyl pyridine) (P2VPy) as polymer components and the dihydric phenols 4,4’-thiodiphenol (TDP) and 4,4’-methylendiphenol (MDP) as low molecular weight compounds, was studied by DSC and FTIR. Thermal properties, such as the glass the glass transition of P4VPy and the melting of TDP and MDP, were found to be clearly affected when the compounds were blended, which was attributed to the miscibility between them. When P2VPy was the macromolecular component, a difference was observed in the DSC behavior, which was attributed to a steric hindrance effect. The formation of intermolecular hydrogen bonds was discovered by FTIR.

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REINTERPRETATION OF THE FIRST STEP OF THE SEQUENTIAL EXTRACTION PROPOSED BY THE SMT

M. Rocco*, M. A. Rubio

Laboratorio de Cinética y Química Ambiental, Departamento de Ciencias del Ambiente, Facultad de Química y Biología, Universidad de Santiago de Chile. Casilla 40, correo 33, Santiagoemail :marcelo.rocco@usach.cl

This study proposes a new approximation to the first step of the sequential extraction method of 4 steps from SMT, suggesting that this step is related not only to exchangeable and/or carbonates but sulphate minerals also.

5,6,8,12b-TETRAHYDRODIOXOLO[4,5-g]ISOINDOLO[1,2-a] ISOQUINOLIN-8-ONE ANTONIO GALDÁMEZ,a VICENTE CASTRO-CASTILLO,a,b BRUCE K. CASSELS a

aDepartamento de Química, Facultad de Ciencias, U. de Chile. bDepartamento de Química, UMCE.

The compound crystallizes as a single enantiomer in the space group Pca21 (No. 29) with a = 27.034(5) Å, b = 4.5093(9) Å, c = 10.667(2)Å, V = 1300.4(4) Å3 and Z = 4. The crystal structure has intermolecular C-H-----O interactions resulting in chains that run along the crystallographic c-axis.