bluuebunny/crossref_metadata_2025 huggingface dataset:
Malachite Green Dye Removal Using the Seaweed Enteromorpha
Authors: Jayaraj R. , Mohan M. Chandra , Prasath P. Martin Deva , Khan T. Hidhayathullah
Published: April 2012

Malachite green adsorption from an aqueous solution onto activated Enteromorpha carbon has been studied experimentally using batch adsorption method. Adsorption kinetics and equilibrium were investigated as a function of initial dye concentration, pH, contact time and adsorbent dosage. Kinetics studies indicated that the adsorption followed pseudo second order reaction. Equilibrium data was analyzed using Langmuir and Freundlich isotherm models. The adsorption capacity of Enteromorpha was found to be 94.74%. On the basis of experimental results and the model parameters, it can be inferred that the carbonaceous Enteromorpha is effective for the removal of malachite green from aqueous solution.
Visualizing High‐Order Symmetric Tensor Field Structure with Differential Operators
Authors: McGraw Tim , Kawai Takamitsu , Yassine Inas , Zhu Lierong
Published: April 2012

The challenge of tensor field visualization is to provide simple and comprehensible representations of data which vary both directionally and spatially. We explore the use of differential operators to extract features from tensor fields. These features can be used to generate skeleton representations of the data that accurately characterize the global field structure. Previously, vector field operators such as gradient, divergence, and curl have previously been used to visualize of flow fields. In this paper, we use generalizations of these operators to locate and classify tensor field degenerate points and to partition the field into regions of homogeneous behavior. We describe the implementation of our feature extraction and demonstrate our new techniques on synthetic
data sets of order 2, 3 and 4.
Association between Cognitive Distortion, Type D Personality, Family Environment, and Depression in Chinese Adolescents
Authors: Zhang Yong , Li Hengfen , Zou Shaohong
Published: April 2012

Purpose. Depression prevalence and risk increase among adolescents are related to biological, psychosocial, and cultural factors. Little is known about the association between cognitive distortion, type D personality, family environment, and depression. The aim of this paper was to examine the relationships of cognitive distortion, type D personality, family environment, and depression in a sample of Chinese adolescents.Methods. A sample of Chinese adolescents with depression and the controls were investigated cross-sectionally with life orientation test-revised (LOT-R), type D personality Scale-14 (DS14), family environment scale (FES), and Zung self-depression scale (SDS); respectively, all scales were administered in Chinese.Results. Chinese-depressed adolescents showed more cognitive distortion, type D personality, and adverse family environment than control groups. Furthermore, lower level of Optimism, negative affectivity, and poor family cohesion may increase the risk of depression in Chinese adolescents.Conclusions. Our study indicates that lower level of Optimism, Negative Affectivity, and poor Family Cohesion factors were implicated to contribute to depression in Chinese adolescents. Lower level of optimism and negative affectivity may be crucial associated factors of depression among these samples. our findings pointed to the importance of broad screening and intervention of vulnerable population.
Evaluation of Stability of Complexes of Inner Transition Metal Ions with 2‐Oxo‐1‐pyrrolidine Acetamide and Role of Systematic Errors
Authors: Sharma Sangita , Ramani Jayesh , Patel Dhara , Patel Ketan , Kadiya Mahesh
Published: April 2012

BEST FIT models were used to study the complexation of inner transition metal ions like Y(III), La(III), Ce(III), Pr(III), Nd(III), Sm(III), Gd(III), Dy(III) and Th(IV) with 2‐oxo‐1‐pyrrolidine acetamide at 30 °C in 10%, 20, 30, 40, 50% and 60% v/v dioxane‐water mixture at 0.2 M ionic strength. Irving Rossotti titration method was used to get titration data. Calculations were carried out with PKAS and BEST Fortran IV computer programs. The expected species like L, LH+, ML, ML2 and ML(OH)3, were obtained with SPEPLOT. Stability of complexes has increased with increasing the dioxane content. The observed change in stability can be explained on the basis of electrostatic effects, non electrostatic effects, solvating power of solvent mixture, interaction between ions and interaction of ions with solvents. Effect of systematic errors like effect of dissolved carbon dioxide, concentration of alkali, concentration of acid, concentration of ligand and concentration of metal have also been explained here.
Investigation of Complexation of Linear Poly(N‐vinyl‐2‐pyrrolidone) with Poly(methacrylic acid‐co‐methyl methacrylate) Gel
Authors: Liu Guoqin , Yan Guojin , Zou Wenjun , Li Zhengxin
Published: April 2012

The contraction of poly(methacrylic acid‐co‐methyl methacrylate) (P(MAA‐co‐MMA)) gel induced by complexation with linear poly(N‐vinyl‐2‐pyrrolidone) (PVP) is quite different from that of poly(acrylic acid) (PAA) or poly(methacrylic acid) (PMAA) gel. It was found that the concentration of PVP has a strong effect on the complexation with P(MAA‐co‐MMA) gel. When PVP was introduced into the P(MAA‐co‐MMA) network, its dynamic mechanic properties vary greatly between complexed and uncomplexed networks. It had the following results: (1) the higher modulus ratio; (2) a slight contraction of gel.
Stability Constants of Mixed Ligand Complexes of Cu(II) and Ni(II) with Some Amino Acids and Phosphates
Authors: Adam Aruna , Verma Suman , Seth Gita
Published: April 2012

The binary and ternary metal complexes of Cu(II) & Ni(II) with some amino acids (leucine, isoleucine & serine) as primary ligand and pyrophosphate (PP), adenosine‐5´‐triphosphate (ATP), as secondary ligand have been studied potentiometrically at 35 °C and a constant ionic strength (1.0 mol dm-3 KNO3). The formation of various binary and ternary complexes has been inferred from the corresponding titration curves. The Irving & Rossotti titration technique has been applied to determine the formation constants corresponding to various complexation equilibria.
Application of Green Chemistry Principle in Synthesis of Phenytoin and Its Biogical Evaluation as Anticonvulsant Agents
Authors: Kadam Abhijit , Jangam Sampada , Oswal Rajesh
Published: April 2012

Phenytoin (5,5′‐dipenylimidazolidine‐2,4‐dione) is the prime example of anticonvulsant agent. According to reported procedure, it is synthesized by condensation of benzil and urea in presence of base (30% w/v NaOH) using ethanol as solvent which itself acts as CNS stimulant. Removal of solvent after synthesis is most difficult and non‐assured process. In case of phenytoin transformation in polymorphism plays an important role when solvent other than water is used. About 30% extra cost is calculated if solvent other than water is used. Therefore by application of green chemistry principle phenytoin was synthesized by condensation of benzil and urea in presence of base (30% NaOH) and water as green solvent. This compound was characterized on the basis of its spectral (IR, 1H NMR) data and evaluated for anticonvulsant activity using MES induced and PTZ induced seizure models in Swiss albino mice. Significant anticonvulsant activity was found by using 25 mg/kg and 50 mg/kg of phenytoin compared with standard phenytoin at 25 mg/kg dose.
Conquering Mount Fuji: Resolution of Tension Pneumocephalus with a Foley Urinary Catheter
Authors: Nimjee Shahid M. , Zomorodi Ali R. , Adamson D. Cory
Published: April 2012

Tension pneumocephalus is the presence of air or gas in the cranium that is under pressure. It occurs due to disruption of the skull, including trauma to the head or face, after neurosurgical procedures and occasionally, spontaneously (Schirmer et al., 2010). Patients typically present with headache but can also have neurological deficits such as decreased mental status, numbness, and weakness (Schirmer et al., 2010). It is diagnosed by computerized tomography (CT) scan (Michel, 2010). The characteristic finding is that the two frontal poles of the brain are separated by air. After diagnosis, treatment is imperative for both symptomatic relief and preventing further compression. We present a case of a patient who presented with tension pneumocephalus and unconventional treatment that resulted in clinical improvement of his symptoms and radiographic resolution of his condition.
Synthesis and Spectroscopic Characterization of Lead(II)bis{O,O′‐ditolyldithiophosphates} and their Adducts with 2,2′‐Bipyridyl and 1,10‐Phenanthroline
Authors: Chaturvedi Disha Jain Alok , Upadhayay R.K.
Published: April 2012

The reaction of lead(II) dichloride with ammonium salts of O,O′‐ditolyldithiophosphoric acid have been carried out in 1:2 molar ratio by refluxing in benzene. These compounds have been further used to synthesize the adduct of the type lead(II)bis{O,O′‐ditolyldithiophosphates}.2,2′‐bipyridyl and lead(II)bis {O,O′‐ditolyldithiophosphates}.1,10‐phenanthroline by the reaction of lead(II)bis{O,O′‐ditolyldithiophosphates} and 2,2′‐bipyridyl and 1,10‐phenanthro‐line in the presence of unimolar dichloromethane and ethanol. All these complexes have been characterized by spectroscopic techniques such as IR, 1H NMR and 31P NMR. On the basis of spectroscopic studies tetracoordinated nature of lead atom in ditolyldithiophosphates complexes and hexacoordinated nature in their adducts have been established.
Planetary Satellite Orbiters: Applications for the Moon
Authors: Carvalho Jean Paulo dos Santos , de Moraes Rodolpho Vilhena , Prado Antônio Fernando Bertachini de Almeida
Published: April 2012

Low‐altitude, near‐polar orbits are very desirable as science orbits for missions to planetary satellites, such as the Earth′s Moon. In this paper, we present an analytical theory with numerical simulations to study the orbital motion of lunar low‐altitude artificial satellite. We consider the problem of an artificial satellite perturbed by the nonuniform distribution of the mass of the Moon (J2–J5, J7, and C22). The conditions to get frozen orbits are presented. Using an approach that considers the single‐averaged problem, we found families of periodic orbits for the problem of an orbiter travelling around the Moon, where frozen orbits valid for long periods of time are found. A comparison between the models for the zonal and tesseral harmonics coefficients is presented.
Theoretical Evaluation of Ultrasonic Velocities in Ternary Liquid Mixtures of Dibutylether + Toluene + 1‐Alkanols at 303K
Authors: Sumathi T. , Abeetha K.
Published: April 2012

A comparison of ultrasonic velocity evaluated from Nomoto’s relation, Van Deal‐Vangeel ideal mixtures relation, impedance dependence relation and collision factor theories with experimental values have been made in three ternary systems of 1‐alkanol with common binary mixture of toluene and dibutylether at 303 K. The relative applicability of these theories to the present systems has been checked and discussed.
Simultaneous Determination by Gas Chromatography of Lindane and Carbaryl in Combined Formulations
Authors: Sen Indrajit , Shandil Ajay , Aggarwal Manjeet , Khandal Rakesh Kumar
Published: April 2012

A gas chromatographic method developed and validated for simultaneous determination of lindane and carbaryl for quality evaluation of lindane‐carbaryl granule, using a glass capillary HP5 column (30 m x 0.32 mm; 0.25 μm), temperature programming with flame ionization detector and dibutylphthalate as an internal standard. The calibration graphs were found linear in the concentration range of 1 μg/mL to 1000 μg/mL for both lindane and carbaryl with correlation coefficient of 0.999 and 0.999 respectively and co‐efficient of variation for intra‐day and inter‐day repeatability studies at different concentration levels was found to be less than 2%. The accuracy of method ranges between 98.5% to 100.8%. Specificity and robustness were also within the acceptable range. The method is highly sensitive with LOD and LOQ as 0.5 and 2 μg/mL for lindane and carbaryl respectively. The method has been tried on several formulations of lindane‐carbaryl granules for quality control and has been found to be applicable.
Theoretical Prediction of Ultrasonic Velocity in Binary Liquid Mixtures
Authors: Babu Shaik.
Published: April 2012

Theoretical values of ultrasonic velocity in the binary mixtures of chlorobenzene with benzene have been evaluated at different temperatures from 303.15 K‐323.15 K using Nomoto′s relation, ideal mixture relation, Junjie′s method, collision factor theory and free length theory. Theoretical values were compared with the experimental values and the validity of the theories was checked by applying the chi‐square test for goodness of fit and by calculating the average percentage error (APE).
Effective Extraction of Heavy Metals from their Effluents Using Some Potential Ionic Liquids as Green Chemicals
Authors: Rajendran A. , Ragupathy D. , Priyadarshini M. , Magesh A. , Jaishankar P. , Madhavan N. S. , Sajitha K. , Balaji S.
Published: April 2012

Synthesis of nine Task Specific Ionic liquids (TSILs), their characterization using 1H NMR spectral studies and other physical properties and potential applications in the removal of certain heavy metals such as Nickel, Iron, Zinc, Copper and Lead has been studied. The removal of these heavy metals from the industrial effluents / contaminated water bodies using these ionic liquids has been proved to be more successful than conventional methods such as precipitation, cementation, reverse osmosis, ion exchange and adsorption.
Removal of Direct Yellow 12 from Water Samples by Cloud Point Extraction Using Triton X‐100 as Nonionic Surfactant
Authors: Abedi Shahnaz , Nekouei Farzin
Published: April 2012

A surfactant mediated cloud point extraction (CPE) procedure has been developed to remove color from wastewater containing direct yellow 12 (Chrysophenine G), using triton x‐100 (TX‐100) as nonionic surfactant. The effects of the concentration of the surfactant, pH, temperature and salt concentration on the different concentration of dye have been studied and optimum conditions were obtained for the removal of direct yellow 12 (DY 12). The concentration of DY 12 in the dilute phase was measured using UV‐Vis spectrophotometer. It was found that the separation of phases was complete and the recovery of DY 12 was very effective in the presence of NaCl as an electrolyte. The results showed that up to 600 mg L−1 of DY 12 can quantitatively be removed (>96%) by Cloud point extraction procedure in a single extraction using optimum conditions.
H‐Point Standard Addition Method for Simultaneous Determination of Eosin and Erytrosine
Authors: Kaur Amandeep , Gupta Usha
Published: April 2012

A new, simple, sensitive and selective H‐point standard addition method (HPSAM) has been developed for resolving binary mixture of food colorants eosin and erythrosine, which show overlapped spectra. The method is based on the complexation of food dyes eosin and erythrosine with Fe(III) complexing reagent at pH 5.5 and solubilizing complexes in triton x‐100 micellar media. Absorbances at the two pairs of wavelengths, 540 and 550 nm (when eosin acts as analyte) or 518 and 542 nm (when erythrosine act as analyte) were monitored. This method has satisfactorily been applied for the determination of eosin and erythrosine dyes in synthetic mixtures and commercial products.
Thermal Decomposition Kinetics of Labile Chromium Complex with Benzoic Acid
Authors: Mishra M. K. , Misra N. M.
Published: April 2012

Complex [CrO2 (C7H5O2) C2H5OH) (H2O)2] was prepared by using benzoic acid. Its spectral characterization was done by using Elemental analysis (C and H), Inductively coupled plasma optical emission spectroscopy (ICP ‐ OES), Ultraviolet ‐ visible (UV‐Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy and Fast Atomic Bombardment (FAB) Mass spectrometry. Whereas thermal decomposition was investigated by differential scanning calorimetric (DSC). The low value of activation energy of exothermic change indicated lability of complex.
Molecular Iodine: A Versatile Catalyst for the Synthesis of 2H‐indazolo[2,1‐b]phthalazine‐1,6,11(13H)‐trione Derivatives in Ethanol
Authors: Wang Xiao , Lu Guangzhou , Ma Weiwei , Wu Liqzang
Published: April 2012

An efficient method for the synthesis of 2H‐indazolo[2,1‐b] phthalazine‐1,6,11(13H)‐trione derivatives by a three‐component condensation reaction of dimedone, aromatic aldehydes and phthalhydrazide in the presence of a catalytic amount of molecular iodine in ethanol is described.
Synthesis, Spectral Characterization and Biocidal Studies of Copper(II) Complexes of Chromen‐2‐one‐3‐carboxy Hydrazide and 2‐(Chromen‐3′‐onyl)‐5‐(aryl)‐1,3,4‐oxadiazole Derivatives
Authors: Mathew Glory , Krishnan R. , Antony Molly , Suseelan M. S.
Published: April 2012

Copper(II) complexes of chromen‐2‐one‐3‐carboxyhydrazide and 2‐(chromen‐3′‐onyl)‐5‐(aryl)‐1,3,4‐oxadiazole derivatives have been synthesized. The structural features have been determined from their microanalytical, magnetic susceptibility, molar conductance, IR, UV Vis, 1H NMR and ESR spectral data. All the Cu(II) complexes exhibit the composition Cu(Ln)2X2; where L1= chromen‐2‐one‐3‐carboxy hydrazide, L2 = 2‐(chromen‐3′‐onyl)‐5‐(2ʺ‐hydroxy phenyl)‐1,3,4‐oxadiazole, L3 = 2‐(chromen‐3′‐onyl)‐5‐(4ʺ‐nitrophenyl)‐1,3,4 ‐oxadiazole and L4 = 2‐(chromen‐3′‐onyl)‐5‐(4ʺ‐chlorophenyl)‐1,3,4‐oxadiazole; X = Cl-, Br-, NO3-, CH3COO-, ClO4- and CNS-. The N, O donor ligands act as a bidentate ligand in all the complexes. Distorted octahedral geometry for all the Cu(II) complexes is proposed. Molecular modeling studies have been made for the rapid structure building, geometry optimization and molecular display. These complexes show the conductance values, supporting their non‐electrolytic nature. The monomeric nature of the complexes was confirmed from their magnetic susceptibility values. These complexes have been screened for their antimicrobial activities against some bacterial species like S.aureus, E.coli, Pseudomonas aeruginosa and few fungal strains C.albicans and Cryptococcus neoformans.
Chemical Composition of the Essential Oil of Cyperus Conglomeratus Rottb. from Iran
Authors: Feizbakhsh A. , Naeemy A.
Published: April 2012

The compositions of the essential oil from cyperus conglomerates were obtained by hydrodistillation and analyzed by GC/MS (Gas chromatography/mass spectrometry). Twenty seven compounds were identified. Of which the cyperene (27.2%) was the major component. This is the first time that an oil of C. conglomerates has been found with cyperene as the major constituent. Also, the oil of C. conglomerates consisted mainly of sesquiterpene hydrocarbons, oxygenated sesquiterpenes and a small percentage of monoterpenes.
Consensus Guidelines for CSF and Blood Biobanking for CNS Biomarker Studies
Authors: Teunissen Charlotte E. , Tumani Hayrettin , Bennett Jeffrey L. , Berven Frode S. , Brundin Lou , Comabella Manuel , Franciotta Diego , Federiksen Jette L. , Fleming John O. , Furlan Roberto , Hintzen Rogier Q. , Hughes Steve G. , Jimenez Connie R. , Johnson Michael H. , Killestein Joep , Krasulova Eva , Kuhle Jens , Magnone Maria-Chiara , Petzold Axel , Rajda Cecilia , Rejdak Konrad , Schmidt Hollie K. , van Pesch Vincent , Waubant Emmanuelle , Wolf Christian , Deisenhammer Florian , Giovannoni Gavin , Hemmer Bernhard
Published: April 2012

There is a long history of research into body fluid biomarkers in neurodegenerative and neuroinflammatory diseases. However, only a few biomarkers in cerebrospinal fluid (CSF) are being used in clinical practice. Anti-aquaporin-4 antibodies in serum are currently useful for the diagnosis of neuromyelitis optica (NMO), but we could expect novel CSF biomarkers that help define prognosis and response to treatment for this disease. One of the most critical factors in biomarker research is the inadequate powering of studies performed by single centers. Collaboration between investigators is needed to establish large biobanks of well-defined samples. A key issue in collaboration is to establish standardized protocols for biobanking to ensure that the statistical power gained by increasing the numbers of CSF samples is not compromised by pre-analytical factors. Here, consensus guidelines for CSF collection and biobanking are presented, based on the guidelines that have been published by the BioMS-eu network for CSF biomarker research. We focussed on CSF collection procedures, pre-analytical factors and high quality clinical and paraclinical information. Importantly, the biobanking protocols are applicable for CSF biobanks for research targeting any neurological disease.
Preparation and Characterization of Nanocrystalline Hard Chromium Coatings Using Eco‐Friendly Trivalent Chromium Bath
Authors: Protsenko V. S. , Gordiienko V. O , Danilov F. I. , Kwon S. C.
Published: April 2012

A new aqueous sulfate trivalent chromium bath is described. The chromium bath contains formic acid and carbamide as complexing agents. Chromium was deposited at a temperature of 30÷40 oC and a cathode current density of 10÷25 A dm-2. The bath allows obtaining thick (up to several hundred micrometers) hard chromium coatings with nanocrystalline structure. The electrodeposition rate reaches 0.8÷0.9 µm min-1.
Spectophotometric Study of Interaction between Sodium Carrageenate and Cationic Dyes
Authors: Nandini R. , Vishalakshi B.
Published: April 2012

The interaction of two cationic dyes, namely, methylene (MB) and acridine orange (AO) with an anionic polyelectrolyte, namely, sodium carrageenate (NaCar) has been investigated by spectrophotometric method and spectrofluorimetric method. The polymer induced metachromasy in the dyes resulting in the shift of the absorption maxima of the dyes towards shorter wavelengths.The stability of the complexes formed between acridine orange and sodium carrageenate was found to be lesser than that formed between methylene blue and sodium carrageenate. This fact was further confirmed by reversal studies using alcohols, urea, surfactants and electrolytes. The interaction parameters revealed that binding between acridine orange and sodium carrageenate was mainly due to electrostatic interaction while that between methylene blue and carrageenate is found to involve both electrostatic and hydrophobic forces. The effect of the structure of the dye and its relation to metachromasy has been discussed.
Effect of Silver Nanoparticle Size on Efficiency Enhancement of Dye-Sensitized Solar Cells
Authors: Photiphitak Chanu , Rakkwamsuk Pattana , Muthitamongkol Pennapa , Sae-Kung Chaiyuth , Thanachayanont Chanchana
Published: April 2012

Titanium dioxide/silver (TiO2/Ag) composite films were prepared by incorporating Ag in pores of mesoporous TiO2films using a photoreduction method. The Ag nanoparticle sizes were in a range of 4.36–38.56 nm. The TiO2/Ag composite films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The TiO2and TiO2/Ag composite films were then sensitized by immersing in a 0.3 mM N719 dye solution and fabricated for conventional dye-sensitized solar cells (DSCs).J-Vcharacteristics of the TiO2/Ag DSCs showed that the Ag nanoparticle size of 19.16 nm resulted in the short circuit current density and efficiency of 8.12 mA/cm2and 4.76%.
Synthesis and Oral Hypoglycemic Activity of 3‐[5′‐Methyl‐2′‐aryl‐3′‐(thiazol‐2ʺ‐yl amino) thiazolidin‐4′‐one]coumarin Derivatives
Authors: Kini Deepthi , Ghate Manjunath
Published: April 2012

Number of heterocyclic compounds has been exploited to develop pharmaceutically important molecules, out of which biheterocyclic coumarins are clinically used potential drug candidates showing oral hypoglycemic and antidiabetic activities. A new series of 3‐[5′‐methyl‐2′‐aryl‐3′‐(thiazol‐2ʺ‐yl amino)thiazolidin‐4′‐one]coumarin derivatives were designed and synthesized. The title compounds were synthesized from starting material 3‐ acetyl coumarin. All the synthesized compounds were characterized and screened for hypoglycemic activity. Some of the compounds exhibited promising activity.
Construction of Tb3+ PVC‐MembraneElectrode Based on N,N’‐Bis(pyrrolylmethylene)‐2‐aminobenzylamine
Authors: Zamani Hassan Ali , Rafati Zynab , Meghdadi Soraia
Published: April 2012

In this work, we report as new Tb3+‐PVC membrane sensor based on N,N’‐bis(pyrrolylmethylene)‐ 2‐aminobenzylamine (PMA) as a suitable ion carrier. Poly vinylchloride (PVC)‐based membrane composed of PMA with oleic acid (OA) as anionic additives and acetophenone (AP) as plasticizing solvent mediators. The Tb3+ sensor exhibits a Nernstian slope of 19.7±0.4 mV per decade over the concentration range of 1.0×10-5 to 1.0×10-2 M and a detection limit of 4.6×10-6 M of Tb3+ ions. The potentiometric response of the sensor is independent of the solution pH in the range of 2.9–8.1. It has a very short response time, in the whole concentration range (∼5 s). The recommended sensor revealed comparatively good selectivity with respect to most alkali, alkaline earth, some transition and heavy metal ions. It was successfully employed as an indicator electrode in the potentiometric titration of Tb(III) ions with EDTA. The electrode was also employed for the determination of the fluoride ion in two mouth wash preparations and the determination of Tb3+ ions concentration in mixtures of three different ions.
Microwave Assisted Synthesis and Antimicrobial Evaluation of Schiff Bases of Indole‐3‐aldehyde
Authors: Kamaria Priyanka , Kawathekar N. , Chaturvedi Prerna
Published: April 2012

In order to develop new antimicrobial agents, a series of Schiff bases of indole‐3‐aldehyde were synthesized by microwave assisted synthesis by taking DMF as solvent and evaluated for their antimicrobial activity. All the synthesized compounds were characterized by IR, 1HNMR and mass spectral analysis. All compounds were tested against five gram positive and five gram negative bacterial strains and one fungal strain. All compounds exhibited better activity against gram positive strains than against gram negative strains and the compounds were found more active against S.aureus and B.subtilis.
A Comparative Study of the Inclusion Complexes of 2‐[5′‐benzylidene‐2′‐phenyl‐4′‐oxo‐1′, 3′‐thiazolidine]‐1, 3‐benzothiazole and 2‐[5′‐(p-N,N‐dimethylamino‐ benzylidene)‐2′‐phenyl‐4′‐oxo‐1′, 3′‐thiazolidine]‐1, 3‐benzothiazole withβ‐Cyclodextrin
Authors: Panda S. , Dash S. K.
Published: April 2012

The compounds 2‐[5′‐benzylidene‐2′‐phenyl‐4′‐oxo‐1′, 3′‐thiazolidine]‐1, 3‐benzothiazole and 2‐[5′‐(p-N,N‐dimethylamino‐ benzylidene)‐2′‐phenyl‐4′‐oxo‐1′, 3′‐thiazolidine]‐1, 3‐benzothiazole have been synthesized in their purest forms starting from 2‐aminobenzothiazole. The inclusion complexes of the above compounds have been prepared with β‐cyclodextrin to increase their solubility and bioaccessibility in polar medium. The formation of inclusion complexes have been ascertained by study of spectral characteristic before and after inclusion complex formation. The stability of inclusion complexes and nature of interaction between the host and guest are known from the determination of thermodynamic parameters. Further the antibacterial and antifungal activities of the compounds are determined which is found to increase significantly after inclusion complex formation
Synthesis of Glucose Based Water Soluble Molecular Tweezers as Molecular Recognition Scaffolds
Authors: Sharma Lalit
Published: April 2012

Dry heating of 4,4’‐methylenedianiline and N,N’‐dimethyl‐4,4’‐methylenedianiline with 5,6‐anhydro‐1,2‐o‐isopropylidene‐α-D‐glucofuranose afforded molecular tweezers having tertiary amino group linked to C‐6 of the glucose moiety. These molecular tweezers on deprotection with dilute acid yielded water soluble analogs which were explored for the solubilization of neutral arenes viz. naphthalene, biphenyl, durene, fluorene, anthracene and phenanthrene in acidic aqueous medium. These solid liquid extraction studies revealed that 6,6’‐(N,N’‐dimethyl‐4’’,4’’’‐methylenedianilino) bis (α-D‐glucopyranose) causes an approximate 31 fold increase in the solubility of biphenyl in aqueous medium and has best complementarity for naphthalene by forming 1:1 complex.
An Obesity Risk SNP (rs17782313) near theMC4RGene Is Associated with Cerebrocortical Insulin Resistance in Humans
Authors: Tschritter Otto , Haupt Axel , Preissl Hubert , Ketterer Caroline , Hennige Anita M. , Sartorius Tina , Machicao Fausto , Fritsche Andreas , Häring Hans-Ulrich
Published: April 2012

Activation of melanocortin-4 receptor (MC4R) by insulin sensitive neurons is a central mechanism in body weight regulation, and genetic variants in theMC4Rgene (e.g., rs17782313) are associated with obesity. By using magnetoencephalography, we addressed whether rs17782313 affects the cerebrocortical insulin response. We measured the cerebrocortical insulin response by using magnetoencephalography in a hyperinsulinemic euglycemic clamp (versus placebo) in 51 nondiabetic humans (26 f/25 m, age35±3years, BMI28±1kg/m2). The C-allele of rs17782313 was minor allele (frequency23%), and the genotype distribution (TT 30, TC 19, CC 2) was in Hardy-Weinberg-Equilibrium. Insulin-stimulated cerebrocortical theta activity was decreased in the presence of the C-allele (TT33±16fT; TC/CC−27±20fT;P=.023), and this effect remained significant after adjusting for BMI and peripheral insulin sensitivity (P=.047). Cerebrocortical theta activity was impaired in carriers of the obesity risk allele. Therefore, cerebral insulin resistance may contribute to the obesity effect of rs17782313.
Rapid Determination of Aesculin, Aesculetin and Fraxetin in Cortex Fraxini Extract Solutions Based on Ultraviolet Spectroscopy
Authors: Yang Ming , Chen Jia-Lei , Shi Xiu-Feng , Niu Hui-Jue
Published: April 2012

To evaluate the application of ultraviolet spectroscopy for the rapid determination of aesculin, aesculetin and fraxetin in Cortex fraxini extract solutions, ultraviolet spectra of Cortex fraxini extract solutions from different batches were collected in the spectral range from 200 nm to 400 nm. The relationship between ultraviolet spectra and chemical parameters displayed some non‐linear characteristics. Thus, K‐OPLS was proposed to establish the calibration models for the determination of Cortex fraxini extract solutions between the reference data and ultraviolet spectra. The calibration results were achieved for the determination of Cortex fraxini extract solutions. The coefficients of determination in calibration (R2) for aesculin, aesculetin and fraxetin were 0.989, 0.957 and 0.939, while in prediction (R2) were 0.982, 0.979 and 0.962, respectively. And the root‐mean‐square error of prediction (RMSEP) for aesculin, aesculet and fraxetin were 11.99, 3.02 and 1.59 μg/mL. The results demonstrated that ultraviolet spectroscopy could be used for the rapid determination of these three components in Cortex fraxini extract solutions.
Synthesis and Structural Studies on Transition Metal Complexes Derived from 4‐Hydroxy‐4‐methyl–2‐pentanone‐1H‐benzimidazol‐2‐yl‐hydrazone
Authors: Neelamma M. , Rao P. Venkateswar , Anuradha G. H.
Published: April 2012

Transition metal complexes of Cr(III), Fe(III), Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) with a tridentate ligand, 4‐hydroxy‐4‐methyl‐2‐pentanone‐1H‐benzimidazole‐2yl‐hydrazone (H‐HPBH) derived from the condensation of 2‐hydrazinobenzimidazole and diacetone alcohol was synthesized. Characterization has been done on the basis of analytical, conductance, thermal and magnetic data, infrared, 1H NMR, electronic, mass and ESR spectral data. From analytical and thermal data, the stoichiometry of the complexes has been found to be 1:1 (metal: ligand). Divalent complexes have the general formula [M(HPBH)Cl(H2O)2] in octahedral geometry, [M(HPBH)Cl] in tetrahedral and square planar stereochemistries and trivalent complexes [M(HPBH)Cl2(H2O)] in octahedral disposition. Infrared spectral data suggest that the ligand HPBH behaves as a monobasic tridentate ligand with N: N: O donor sequence towards the metal ions. On the basis of the above physicochemical data, octahedral, tetrahedral and square planar geometries were assigned for the complexes. The ligand and metal complexes were screened for their physiological activities against E. coli and S. aureus. The order of physiological activity has been found to be Cu(II) > Ni(II) > Zn(II) > Co(II) > Cr(III) > Mn(II) > Fe (III) > ligand against E.coli and Ni(II) > Cu(II) > Zn(II) > Mn(II) > Cr(III) > Fe(III) > Co(II) > ligand against S. aureus.
Microwave Dielectric Study of Tetramethylurea and N, N‐Dimethylacetamide Binary Mixture in Benzene
Authors: Sharma V. , Thakur N.
Published: April 2012

Dielectric relaxation of the binary mixture of tetramethylurea and N, N‐dimethylacetamide has been studied at fixed frequency and temperature (9.88 GHz & 298 K respectively) in benzene solution. Different dielectric parameters like the dielectric constant (ε′) and the dielectric loss (ε") at microwave frequency, static dielectric constant (ε0) and dielectric constant (ε∞) at optical frequency were determined. The values of relaxation time (τ(1), τ(2), τ(0) & τGK) have been calculated using higasi’s single frequency method and Gopala Krishna’s method. Using Eyring’s rate theory, the activation energies for the process of dielectric relaxation and viscous flow were calculated and compared. The study of dielectric properties of the binary mixture reveals the existence of the solute‐solute type of molecular associations.
Synthesis, Characterization and Epoxidation of cis‐Enriched New Polycarbonates Catalyzed by Efficient Organotin Compound
Authors: Massoudi A. H. , Ramazanian N. , Vahedi H. , Khodabakhshi J.
Published: April 2012

Presence of active functional groups on polymer chain is a suitable aspect of polymer structure which allows performing next favourite reactions on polymer molecule. In this research a novel aromatic derivative of cis‐but‐2‐endiol was synthesized as monomer. The synthesized monomer was polymerized using diphenyl carbonate and 1,4‐butandiol as second and third monomer along with organotin catalyst. Polymerization reaction performed by using melt‐phase transesterification process to produce a new terpolymer of polycarbonate. During the reaction the double bonds are preserved on polymer chain and epoxidized by m‐chloroperbenzoic acid (MCBPA) in good yield to demonstrate the reactivity and possibility of performing further reactions on double bonds of polymer.
Cr(III),Mn(II),Fe(III),Co(II),Ni(II),Cu(II) and Zn(II) Complexes with Diisobutyldithiocarbamato Ligand
Authors: Tarique Mohammad
Published: April 2012

The synthesis of sulphur and nitrogen containing dithiocarbamato ligand derived from diisobutylamine as well as its coordination compounds with 3d series transition metals is presented. These synthesized compounds were characterized on the basis of elemental analysis, conductometric measurements and IR spectral studies. The analytical data showed the stoichiometry 1:2 and 1:3 for the compounds of the types ML2 {M=Mn(II), Co(II), Ni(II), Cu(II) and Zn(II)} and M′L3{M′=Cr(III) and Fe(III)} respectively. The conductometric measurements proved the non‐electrolytic behaviour of all the compounds. The bidentate nature of dithiocarbamato moiety was confirmed on the basis of IR spectral data.
Reaction of N‐(Per‐O‐acetyl‐β‐D‐glucopyranosyl)‐Nʼ‐(4ʼ,6ʼ‐diarylpyrimidine‐2ʼ‐yl)thioureas with Ethyl Bromoacetate
Authors: Thanh Nguyen Dinh
Published: April 2012

Some new 2‐iminothiazolidin‐4‐ones having pyrimidine ring have been synthesized by reaction of substituted N‐(per‐O‐acetyl‐β-D‐glucopyranosyl)‐Nʼ‐(4ʼ,6ʼ‐diarylpyrimidine‐2ʼ‐yl)thioureas with ethyl bromoacetate. The structure of isomeric products has been confirmed by spectroscopic methods, such as IR, 1H and 13C NMR.
Permanence for a Delayed Nonautonomous SIR Epidemic Model with Density‐Dependent Birth Rate
Authors: Yingke Li , Liang Chen , Kai Wang
Published: April 2012

Based on some well‐known SIR models, a revised nonautonomous SIR epidemic model with distributed delay and density‐dependent birth rate was considered. Applying some classical analysis techniques for ordinary differential equations and the method proposed by Wang (2002), the threshold value for the permanence and extinction of the model was obtained.
Ultrasonic Studies on Binary Mixtures of Acetyl Acetone at 301K
Authors: Babu Shaik , Murthy A. Radhakrishna
Published: April 2012

The ultrasonic velocity (U), density (ρ) and viscosity (η) measurements have been carried out for the binary mixtures of acetyl acetone with benzene, carbon tetra chloride and isoamyl alcohol at 301 K. From the measured values of ultrasonic velocity, density and viscosity, parameters such as internal pressure (πi), free volume (Vƒ) and acoustical parameters such as adiabatic compressibility (β), inter molecular free length (Lƒ), acoustic impedance (Z), relaxation time (τ) have been calculated. The results have been analyzed and interpreted in terms of molecular interactions.
Simultaneous Determination of Preservatives (Methyl Paraben and Propyl Paraben) in Sucralfate Suspension Using High Performance Liquid Chromatography
Authors: M. Kashid Rajesh , G. Singh Santosh , Singh Shrawan
Published: April 2012

A reversed phase HPLC method that allows the separation and simultaneous determination of the preservatives methyl paraben (M.P.) and propyl paraben (P.P.) is described. The separations were effected by using an initial mobile phase of water: acetonitrile (50:50) on Inertsil C18 to elute P.P. and M.P. The detector wavelength was set at 205 nm. Under these conditions, separation of the two components was achieved in less than 10 min. Analytical characteristics of the separation such as precision, specificity, linear range and reproducibility were evaluated. The developed method was applied for the determination of preservative M.P. and P.P. at concentration of 0.01 mg/mL and 0.1 mg/mL respectively. The method was successfully used for determining both compounds in sucralfate suspension.
Assessment of Some Heavy Metals in Drinking Water Samples of Tunceli, Turkey
Authors: Kaplan Olcay , Yildirim Nuran Cikcikoglu , Yildirim Numan , Tayhan Nilgun
Published: April 2012

The drinking water quality is associated with the conditions of the water supply networks, the pollution and the contamination of groundwater with pollutants of both anthropogenic and natural origin. In this study, water samples were taken from four different waterworks in Tunceli, Turkey and heavy metals concentrations (As, Cu, Cd, Cr, Pb, Ni and Hg) were measured. Four sampling sites were pre‐defined in different locations of the city. The obtained results showed that, the heavy metals concentrations in water samples did not exceed the values of WHO (World Health Organization), EC (Europe Community), EPA (Environment Protection Agency) and TSE‐266 (Turkish Standard) guidelines.
The Effects of Cassia Siamea Lam. Root Extract on the Corrosion and Kinetics of Corrosion Process of Copper in Alkaline Solutions
Authors: Onen A. I , Nwufo B. T. , Ebenso E. E.
Published: April 2012

The effect of Cassia siamea lam. (CSL) root extract as a corrosion inhibitor of copper in 0.50 M NaOH solutions was investigated using absorbance difference technique at 30 °C and 40 °C. CSL root extract inhibited the corrosion of copper in 0.50 M NaOH solutions and the inhibition efficiency (% IE) increased to a maximum of 78.3±2.3% with increasing concentration of the extract but decreased with increasing temperature. The adsorption of CSL root extract on copper surface followed the Langmuir adsorption model with the average heat of adsorption, Qads and free energy of adsorption, ΔGads of ‐8.98 kJmol-1 and ‐8.70 kJmol-1 respectively. A kinetic treatment of the data revealed a first order kinetics with respect to copper in the presence and absence of the extract.
Determination of Mesalamine Related Impurities from Drug Product by Reversed Phase Validated UPLC Method
Authors: Kanubhai Trivedi Rakshit , Mukesh C Patel , Amit R Kharkar
Published: April 2012

In the present study gradient reversed‐phase UPLC method was developed for simultaneous determination and separation of impurities and degradation products from drug product. The chromatographic separation was performed on acquity UPLC BEH C18 column (50 mm×2.1 mm, 1.7 µm) using gradient elution. Other UPLC parameters which were optimised are flow rate, 0.7 mL/min; detection wavelength, 220 nm; column oven temperature, 40 °C and injection volume 7 µL. Stability indicating capability was established by forced degradation experiments and separation of known degradation products. The method was validated as per International Conference on Harmonization (ICH) guideline. For all impurities and mesalamine, LOQ (limit of quantification) value was found precise with RSD (related standard daviation) of less than 2.0%. In essence, the present study provides an improved low detection limit and lower run time for evaluation of pharmaceutical quality of mesalamine delayed‐release formulation. Moreover, the developed method was successfully applied for quantification of impurities and degradation products in mesalamine delayed‐release formulation. The same method can also be used for determination of related substances from mesalamine drug substance.
Evaluation of Physicochemical Characteristics of Various River Water in India
Authors: Chandra Sulekh , Singh Arendra , Tomar Praveen Kumar , Kumar Adarsh
Published: April 2012

Physicochemical parameters of water samples collected from various rivers in India. Water samples under investigations were collected from Krishana Vijaywada, Gomti Lucknow, Hoogali Kolkata, Ganga Kasi, Mahanadi Katak, Cauveri river Tiruchirapalli station during (July ‐ August) seasons in the year 2009. The different sites show significant enrichment with Zn, Fe, Ni, Cr, Ca and Mg indicating input from industrial sources. The observed values of different physicochemical characteristics like pH, temperature, turbidity, total hardness (TH), iron, chloride, total dissolved solids(TDS), Ca2+, Mg2+, SO42-, F‐ total alkalinity (TA), COD, BOD, phosphate, FRC (Free residual chlorine), total silica and hydrazine of samples were compared with standard values recommended by Bureau of Indian standard (BIS).
Simultaneous Estimation of Gemcitabine Hydrochloride and Capecitabine Hydrochloride in Combined Tablet Dosage Form by RP‐HPLC Method
Authors: Rajesh V. , Anupama B. , Jagathi V. , Praveen P. Sai
Published: April 2012

A new reverse phase high performance liquid chromatography (RP‐HPLC) method has been developed for the simultaneous estimation of gemcitabine hydrochloride and capecitabine hydrochloride in combined tablet dosage form. An inertsil ODS‐3 C‐18 column having dimensions of 250×4.6 mm and particle size of 5 µm, with mobile phase containing a mixture of acetonitrile : water : triethyelamine in the ratio of (70 : 28 : 2v/v) was used. The pH of mobile phase was adjusted to 4.0 with ortho‐phosphoric acid. The flow rate was 1 mL/min and the column effluents were monitored at 260 nm. The retention time for gemcitabine hydrochloride and capecitabine hydrochloride was found to be 2.76 and 2.3 min respectively. The proposed method was validated in terms of linearity, accuracy, precision, limit of detection, limit of quantitation and robustness. The method was found to be linear in the range of 10‐50 µg/mL and 4‐24 µg/mL for gemcitabine hydrochloride and capecitabine hydrochloride, with regression coefficient r = 0.999 and r = 0.999, respectively.
Application of N‐Quinoline‐2‐carboxamido‐8‐aminoquinoline in Fabrication of a Ho(III)‐PVC Membrane Sensor
Authors: Zamani Hassan Ali , Langroodi Samaneh , Meghdadi Soraia
Published: April 2012

The N‐quinoline‐2‐carboxamido‐8‐aminoquinoline (QCA) was used as a suitable ion carrier in the construction of a Ho(III) PVC‐based membrane sensor. This sensor demonstrated good selectivity and sensitivity towards the holmium ion for a broad variety of cations, including alkali, alkaline earth, transition and heavy metal ions. The proposed electrode exhibits a linear dynamic range between 1.0×10-6 and 1.0×10-2 M, with a near Nernstian slope of 20.4±0.3 mV per decade and a detection limit of 4.2×10-7 M. The best performance was obtained with a membrane composition of 30% poly(vinyl chloride), 56% nitrobenzene, 2% sodium tetraphenyl borate, 10% oleic acid and 2% QCA. The potentiometric response of the constructed electrode is pH independent in the range of 2.4‐7.4. The sensor possesses the advantages of short conditioning time, fast response time (∼ 5 s) and especially, good selectivity towards transition and heavy metal and some mono, di and trivalent cations. The Ho3+ sensor was successfully applied as an indicator electrode in the potentiometric titration of Ho(III) ions with EDTA. The electrode was also used for the determination of Ho3+ ions in mixtures of different ions and the determination of the fluoride ion in mouth wash solutions.
Synthesis and Structural Characterization of ‘Non‐VSEPR’ Structures of Oxo‐Tungsten Complex
Authors: Ghammamy Shahriare , Sahebalzamani Hajar
Published: April 2012

The crystal structure of [(CH3)4N]4 [WOCl4F][WO3Cl4] was determined by single crystal x‐ray diffraction technique. The crystal is monoclinic, space group C 2/m, with a= 28.23(10) Å, b= 11.60(4) Å,c= 13.48(5) Å, β=118.43(7)°, V= 3886(2)Å3, Z=4. The structure was solved by direct methods and refined by least‐squares methods to a final R = 0.0512 for 3825 observed reflections with I>2σ(I). In crystal there are two crystallographic distinct anions, both with cis geometry; the O‐W‐F and O‐W‐O angles are 97.5(3)° and 103.1(3) ° respectively. All structures are cis configurations that confirm a preference for angles below 90° and 180° between cis and trans σ‐donor ligands, respectively.
Simultaneous Determination of Paracetamol, Phenylephrine Hydrochloride, Oxolamine Citrate and Chlorpheniramine Maleate by HPLC in Pharmaceutical Dosage Forms
Authors: Pirol Ozan , Sukuroglu Murat , Ozden Tuncel
Published: April 2012

A new high performance liquid chromatographic (HPLC) method was developed for the determination of paracetamol, phenylephrine hydrochloride, oxolamine citrate and chlorpheniramine maleate in combined pharmaceutical formulations and dosage forms. The separation was performed on an Agilent Zorbax SB‐CN column with the mobile phase consisting of 0.02 M phosphate buffer (pH:4) and acetonitrile (85:15,v/v) in flow rate 1.5 mL at 22 °C. The overall retention time of the analytes was 3.5 min. The method was validated with respect to linearity, precision, accuracy and recovery. The relative standard deviation for 10 replicate measurements of paracetamol, phenylephrine HCl, oxolamine citrate and chlorpheniramine maleate were 0.12, 0.36 0.18 and 0.59%, respectively. Total recoveries of analytes were 99.99, 100.56, 100.20 and 99.60%, respectively. No chromatographic interference from the tablet excipients was found. The linearity of paracetamol, phenylephrine HCl, oxolamine citrate and chlorpheniramine maleate were in the range of 20‐120 μg/mL, 0.4‐2.4 μg/mL, 8‐48 μg/mL and 0.16‐0.96 μg/mL, respectively. This simple, fast, economical and precise high performance liquid chromatographic method can be adopted for routine quality control analysis.
Ion Chromatographic Estimation of Arsenite and Arsenate at Trace Level
Authors: Chavan Chetan , Bhate Vijayanand , Thaker Chanakya , Khandkar Aditi
Published: April 2012

Present method shows simple and specific determination of traces of inorganic arsenic in water. This method enables simultaneous determination of arsenite by electrochemical detection and arsenate by suppressed conductivity detection. The applicability of this method was illustrated by determining the inorganic arsenite and arsenate content from bore‐well water and river water samples without any special pretreatment. The present method for direct determination of arsenite and arsenate shows good sensitivity, selectivity, precision and accuracy. Detection limits determined using this procedure was found to be 2.0 μg/L for arsenite and 30.0 μg/L for Arsenate. The simplicity, ease of use, low detection limit and low running cost of this method makes it appealing for increasing capability of testing in the lab.