ID: 56617
Title: Fishes of the Khuiala Formation (early Eocene) of the Jaisalmer basin, Western Rajasthan, India
Author: Kishor Kumar, Rajendra Singh Rana and Hukam Singh
Editor: P. Balaram
Year: 2007
Publisher: Current Science Association, Vol 93, No 4, 25 August 2007
Source: Centre for Ecological Sciences
Reference: None
Subject: Current Science
Keywords: Early Eocene, ichthyofauna, Jaisalmer basin, Khuiala formation, vertebrates
Abstract: A newly discovered assemblage of the Early Eocene (Y presian) fish is recorded from the lower part of the Khuiala Formation of the Jaisalmer Basin, Western Rajasthan. It consists of exceptionally well preserved but mostly isolated teeth and some dermal denticles of fairly diverse ichthyofauna. Based on isolated teeth, 14 taxa belonging to six elasmobranch and five teleostean families have been identified, including a probably new but unnamed species of the nurse shark, Ginglymosoma. Other taxa comprise Galeorhinus sp., Hemiscyllium sp., Rhinobatos sp., Gymnura sp., Heterotorpedo sp., Eutrichiurides sp., Sparus sp., Stephanodus lybicus and Diodon sp. Among these, Hemiscyllium and Coupatezia are new to the subcontinent. Among the Paleocene-Eocene ichthyofaunas documented from India, this Khuiala assemblage is closet to the Lower Eocene fish assemblage from the subsurface Cambay Shale of Vastan Lignite Mine, Surat District, Gujarat. It is a dominantly shallow-water marine assemblage typically lacking coastal freshwater elements.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56616
Title: Unsupervised image segmentation using finite doubly truncated Gaussian mixture model and hierarchical clustering
Author: Srinivas Yarramalle and K Srinivas Rao
Editor: P. Balaram
Year: 2007
Publisher: Current Science Association, Vol 93, No 4, 25 August 2007
Source: Centre for Ecological Sciences
Reference: None
Subject: Current Science
Keywords: EM algorithm, image segmentation, image quality metrices, truncated Gaussian mixture distribution
Abstract: A new image segmentation method based on finite truncated Gaussian mixture model has been proposed. The truncated Gaussian distribution includes several of the skewed and asymmetric distribuions as particular cases with a finite range. It also includes the Gaussian distribution as a limiting case. We used the Estimation Maximization algrithm to estimate the model parameters of the image data and the number of mixture components was estimated using hierarchial clustering algorithm. This algorithm was also utilized for developing the initial estimates of the EM algorithm. Segmentation was carried out by clustering each pixel into the appropriate component according to the maximum likelihood estimation criteria. The advantage of our method lies in its efficiency on initialization of the model parameters and segmenting images in a totally unsupervised manner. Experimental results show that this segmentation method can provide better results than the other methods.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56615
Title: Solar variability in the past and palaeoclimate data pertaining to the southwest monsoon
Author: Manish Tiwari and Rengaswamy Ramesh
Editor: P. Balaram
Year: 2007
Publisher: Current Science Association, Vol 93, No 4, 25 August 2007
Source: Centre for Ecological Sciences
Reference: None
Subject: Current Science
Keywords: Insolation, palaeoclimate, solar variability, southwest monsoon, total solar irradiation
Abstract: A significant part of the earth ' s climate variability is caused by changes in the solar emission. Instrumental observation of the sun gives us some idea about decadal variability in the solar radiation. On longer timescales, we look to paleoclimate proxies to learn about solar variability. In this review we discuss various palaeo-records and what we have learnt from them. In addition, we outline important questions that need to be addressed.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56614
Title: Unique structure and solute-solvent interaction in Imidazolium based ionic liquids
Author: Gonga G, Bustam M A , Man Z and Abdul Mutalib M I
Editor: Dr Shankar Gargh
Year: 2012
Publisher: Research Journal of Chemistry and Environment, Vol 16 (1) March 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: Research Journal of Chemistry and Environment
Keywords: Solute-solvent interaction, Imidazolium based Ionic liquids
Abstract: Ionic liquids have attracted wide attention lately and their potential applications in different areas have been explored. Most of the current researches on ionic liquids are concentrated on investigating what can be done by ionic liquids adn why they work the way they do. The latter provide the insight into the molecular factors that determine their properties raning from quantitative thermodynamic and physical data and qualitative tends that guide in searching the best ionic liquids for particular purpose.
Many of the applications rely upon the interaction of ionic liquids with other components. Ionic liquids exhibit nanoscale phas segregation into polar and nonpolar-regions The nanoscale self organisation is the result of interplay between Coulomb and ban der Waals interactions which leads to the formation of high charge density permeated non-polar regions. This characteristic determines how different molecular solutes interact with certain domain of the ionic liquids and distinct local environment. However, the complexities of the nature and size of cation-anion interactions and intermolecular forces in liquids phase give rise to controversies. This review discusses the current development in understanding molecualr structure, cation-anion interaction, intermolecular forces and their effects of solvation. This work is mainly concentrated on imidazolium based ionic liquids.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56613
Title: Molecular iodine as a catalyst
Author: Mishra Nidhi and Sehegal Preeti
Editor: Dr Shankar Gargh
Year: 2012
Publisher: Research Journal of Chemistry and Environment, Vol 16 (1) March 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: Research Journal of Chemistry and Environment
Keywords: Molecular iodine, catalyst
Abstract: Molecular iodine acts as a catalyst in many organic reactions. It provides an inexpensive and quick method of organic synthesis.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56612
Title: Fixed bed column studies for the removal of managenese using electric arc furnace slag: applying response surface method
Author: Beha C L, Chuah T G , Nourouzi Mohsen and Choong Thomas S Y
Editor: Dr Shankar Gargh
Year: 2012
Publisher: Research Journal of Chemistry and Environment, Vol 16 (1) March 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: Research Journal of Chemistry and Environment
Keywords: Electric arc furnace slag, manganese, Thomas model, BDST model, Response surface method (RSM)
Abstract: This study investigates the ability of the electric arc furnace slag (EAFS) to absorb heavy metal manganese in a fixed bed column. Thomas model was used to predict the break through curves for adsorption of manganese at different flow rate (5-9mLmin-1) while bed-depth/service time (BDST) model was used to express the effect of bed depth (30 - 100 cm) on breakthrough curves. Results showed that the breakthrough curves were dependent on bed depth and flow rate. At the highest bed depth (100 cm) and the lowest flow rate (5 mLmin-1), the maximum adsorption was obtained (109.9 mgg-1according to the Thomas model). Both the BDST model and Thomas model adequately described the adsorption of manganese onto the EAFS while the accuracy of response surface method (RSM) model was slightly higher than that for the Thomas mode (average R2 = 0.99 and 0.91 respectively).
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56611
Title: Kinetics, thermodynamics and breakthrough studies of biosorption of Cr (VI) using Arachis hypogea shell powder
Author: Singh J and Ali A
Editor: Dr Shankar Gargh
Year: 2012
Publisher: Research Journal of Chemistry and Environment, Vol 16 (1) March 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: Research Journal of Chemistry and Environment
Keywords: Activated Arachis hypogea shell powder, kinetics and thermodynamics, Thomas model, biosorption and chromium electroplating effluents
Abstract: Activated Arachis hypogea shell powder has been applied for studying kinetics, thermodynamics and breakthrough studies of Cr(VI) biosorption frm synthetic and electroplating industrial effluents using batch and column processes. To optimize the conditions for the maximum biosorption in batch process, the following parameters have been varied (i) contact time, (ii) initial Cr (VI) concentration, (iii) pH and (iv) adsorbent doses. Both Freundlich and Langmuir adsorption models have been used to study the batch equilibrium data and better fitting was observed with Langmuir model with correlation coefficient of 0.99. The maximum biosorption capacity of Cr (VI) in batch process was found to be 131.57mgg-1 at pH 2 by Langmuir isotherm. The experiments were performed to study the kinetics of the Cr (VI) biosorption and obtained data were best fitted with pseudo-second-order model.
The thermodynamic parameters viz, Gibbs free energy (?G0), enthalpy (?H0) and entropy (?S0) changes were also calculated and the observed values supported the spontaneity of the biosorption process. Two kinetic models viz., Thomas and bed depth service time model were applied to predict the breakthrough curves at different flow rates and bed depths and the best results were obtained when Cr (VI) solution of 50 mgL-1 concentration was used in a bed depth of 20 cm with a flow rate of 2.0 mL -1at 2 pH. The activated Arachis hypogea shell has also been successfully employed for the biosorption of Cr (VI) from electroplating effluents to demonstrate its industrial application.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56610
Title: Removal of reactive red 120 and direct red 81 dyes from aqueous solutions by pumice
Author: Mahvi Amir Hossein and Heibati Behzad
Editor: Dr Shankar Gargh
Year: 2012
Publisher: Research Journal of Chemistry and Environment, Vol 16 (1) March 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: Research Journal of Chemistry and Environment
Keywords: Adsorption, pumice, isotherm, Direct Red 81, Reactive Red 120
Abstract: Dyes are the main pollutants existing in wastewater of textile industries. Dyes are produced naturally or artificial and can cause fabrics to take different colors The main objective of this work was to investigate adsorption of Reactive Red 120 (RR 120) and DIrect Red 81(DR 81) dyes by pumice. This fundamental-practical study was conducted in lab-scale batch system. Chemical structure and composition of Pumice was determined by X-Ray Fluorescence (XRF), Scanning Electron Microscopy (SEM) and electronic microscope. The effects of contact time and initial solution pH on adsorption process were also evaluated. The Freundlich and Langmuir isotherms were used to describe adsorption equilibrium. The results of adsorption isotherm experiments show that the removal of RR 120 and DR 81 dyes follow Langmuir (R2>0.964) and Freundlich (R2>0.932) isotherm models. It was found that the affinity coefficients, Kg, for DR81 and RR 120 dyes were 10.56 and 2.32 respectively, indicating higher adhesion of pumice to DR81 than RR 120 . In general, the results of the study showed that pumice can be used as a cheap and effective adsorbent for removal of dye from textile industrial effluents.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56609
Title: Advanced treatment for coke-plant effluents by Fenton oxidation together with adsorption of modified Fly ash
Author: Tang Hai
Editor: Dr Shankar Gargh
Year: 2012
Publisher: Research Journal of Chemistry and Environment, Vol 16 (1) March 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: Research Journal of Chemistry and Environment
Keywords: Coke-plant wastewater, Fenton reaction , kinetics , adsorption , fly ash
Abstract: The advanced treatment of coke-plant effluents was conducted by Fenton oxidation together with adsorption of modified fly ash (MFA). It was observed that pH of 3.0 and MFA dose of 6.0 gL-1were the optimum vlaues for MFA adsorption, about a percent COD removal of 72.7% was achieved. Adsorption isotherms indicated that the adsorption of COD could be very well described by the Freundlich isotherms. The percent COD removal increased with the increasing of molar ratio of [Fe2+]/[H2O2] from 0.02 to 0.3 and decreased with a continuous increasing of the ratio by Fenton. The highest percent COD removal of 97.3 % by Fenton oxidation was obtained at the experimental conditions: pH of 4, ratio of 0.08, H2O2 dosage of 30 mM. The coke wastewater by Fenton degradation can be adequately described by the pseudo-first-order kinetics model which fitted well with all reactions.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56608
Title: Dairy wastewater treatment by anaerobic hybrid reactor-a study on the reactor performance and optimum percentage of inert media fill inside reactor
Author: Sathyamoorthy G L and Saseetharan M K
Editor: Dr Shankar Gargh
Year: 2012
Publisher: Research Journal of Chemistry and Environment, Vol 16 (1) March 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: Research Journal of Chemistry and Environment
Keywords: Anerobic hybrid reactor, inert media, dairy wastewater, biomass, agitation
Abstract: Industries which use water as their raw material or in their process are commonly known as Wet Industries. The dairy industry is one of the major industries which generate three litres of waste water while processing oen liter of milk. In the present study an attempt has been made to treat dairy wastewater using the Anaerobic Hybrid Reactor (AHR) which offers the advantages of Upflow Anaerobic Sludge Blanket Reactor (UASBR) and Upflow Anaerobic Filter Reactor (UAFR). The man characteristics of AHR are use of sludge blanket at the bottom of the reactor and a region of attached biomass on inert "media in the upper portion of the reactor. THe inert media in the AHR aer used to increase the solids retention time, to provide enough surface area for attachment of biomass and to avoid the short circuiting of the influent.
In order to determine the optimal inert media fill percentage inside the reactor, for better mixing and fluidization, an air hydrodynamic study was carried out with different percentage of inert media and the results were analyzed. The study reveals that the 60% of volume of the reactor could be filled with inert media for the better performance of the Anaerobic Hybrid Reactor without clogging and washout of biomass.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56607
Title: Batch studies and effect of environmental parameters on microbial degradation of perchlorate using acclimatized effluent sludge
Author: Anoop Raj J R and Muruganandan L
Editor: Dr Shankar Gargh
Year: 2012
Publisher: Research Journal of Chemistry and Environment, Vol 16 (1) March 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: Research Journal of Chemistry and Environment
Keywords: Perchlorate, nitrate, pH, salinity, ORP, biodegradation, batch reactor, MLSS
Abstract: Perchlorate (ClO4-) is a soluble anion which is widely used in explosive industries, rocket fuel manufacturing plants, demilitarization of weaponry and so on. It causes serious health implications in human by impairing the function of thyroid gland. Hence there is an urge to develop technologies for perchlorate remediation in contaminated sites or contaminated water. Present work deals with the laboratory scale study of perchlorate degradation using an acclimatized effluent sludge and the effect of various environmental parameters on its degradation. Anaerobic biodegradation of perchlorate was carried out in a laboratory scale batch reactor using a mixed microbial consortium. Perchlorate reduction was monitored through routine analysis of parameters like pH, oxidation-reduction potential (ORP), salinity, ClO4- concentration using ion selective electrode and mixed liquor suspension solid (MLSS) levels. Perchlorate degradation in the absence of nitrate was more rapid compared to cells grown on perchloate and nitrate mixture. The optimum pH and salinity for the reductive bioremediation by perchlorate enriched microbial consortium was found to be 8.0 and 0.25% NaCl. The stochiometric requirement level of ClO4-to acetate for the effective degradation was found to be in 1:2 ratio.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56606
Title: Properties of Jute pulps prepared from ethanol-water pulping process
Author: Sahin Halil Turgut
Editor: Dr Shankar Gargh
Year: 2012
Publisher: Research Journal of Chemistry and Environment, Vol 16 (1) March 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: Research Journal of Chemistry and Environment
Keywords: Organosolv pulping, lignin, ethanol, non-wood pulping, pulp properties
Abstract: A number of ethanol (EtOH) - water based pulping trials was carried out to produce a jute pulp with low residual lignin content and high physical properties. The effects of pulping conditions on the yield, degree of delignification and selected physical properties were evaluated. It was found that the delignification ability of ethanol-water system for jute was moderate at low temperatures. It was necessary to use high temperature and longer cooking times to give sufficient delignification. However, the extended delignification with increasing temperature, strongly affect the strength properties. The highest burst strength of 1.8 kPa m2/g, tear strength of 9.6 mN m2/g and tensile stength of 32.3 N mg/g were found at various reaction times and temperatures in ethanol (EtOH)-water pulping trials.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56605
Title: Benzophenone constituents from the roots of Garcinia eugenifolia
Author: Jong Vivien Yi Mian, Ee Gwendoline Cheng Lian, Sukaria Mohd Aspollah, Taufiq-Yapa Yun Hin, Khong Heng Yen and Chan Margaret Kit Yok
Editor: Dr Shankar Gargh
Year: 2012
Publisher: Research Journal of Chemistry and Environment, Vol 16 (1) March 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: Research Journal of Chemistry and Environment
Keywords: Garcinia eugenifolia, benzophenone, triterpenoid, xanthone
Abstract: Our recent phytochemical investigation on the roots of Garcinia eugenifolia gave a new benzophenone, (3,4-dihydroxyphenyl) (3-hydoxy-5-metho-xyphenyl) methanone (1), one other benzo-phenone, (3-hydroxy-phenyl) 3,4,5-Trihydroxyp-henyl) methanone (2), together with four triterpenoids, magniferolic acid (3), euphadienol (4), -sitosterol (5) and friedelin (6)as well as two xanthones, 5, 9 - dihydroxy-8-methoxy-2,2-dimethyl-7-(3-methylbut-2-enyl) Pyranol [3,2-b] xanthen-6 (2H)-one (7) and 1,3,6,8-tetrahyd roxyxant -hone (8). The structures of these compounds were fully characterised by NMR spectroscopic analysis.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56604
Title: Removal of Copper (II) and Nickel (II) using Mangifera indica (Mango) bark
Author: Sahare A B
Editor: Dr Shnkar Gargh
Year: 2012
Publisher: Research Journal of Chemistry and Environment, Vol 16 (1) March 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: Research Journal of Chemistry and Environment
Keywords: Copper and Nickel, mango tree bark, adsorption, column study, breakthrough curve, Fruendlich isotherm, metal removal
Abstract: Dried and powdered tree bark of Mangifera indica (Mango) has been used for the removal of Cu(II) and Ni(II) metal ions from synthetically prepared wastewater. The adsorption process was studied as a function of pH (2-9), contact time (0-120 min), initial concentration (20-55 mg/L), doses of bark (1-4 g) and temperature (32-900C). It was observed that the pH has marked effect on Cu(II) and Ni(II) uptake. Result shows that about 80% removal of Cu(II) an about 90% removal of Ni(II) takes place over the pH range of 5-6 and contact time of 1 hour at initial concentration of 20 mg/L. The adsorption of Cu(II) and Ni(II) was tested by Fruendlich adsorption isotherm and is inversely related to the temperature. The bark was found to be efficient media for removal of Cu(II) and Ni(II) in continuous mode using fixed bed column. The column having 2 cm diameter with bed depth of 30 cm was used for the treatment of water containing Cu (II) and Ni (II) separately at concentration of 20 mg/L and flow rate 9.5 ml/min. The column parameter like adsorption at different time intervals was studied. The isotherm data were compared with experimental breakthrough curve. 0.01N HNO3 solution was used for desorption of adsorption column and column regenerated using distilled water.
Location: 241
Literature cited 1: None
Literature cited 2: None
ID: 56603
Title: Kinetics and mechanism of oxidation of benzyl phenyl ethers by N-chloronicotinamide in aqueous acetic acid medium
Author: Priya V and Mathiyalagan N
Editor: Dr Shnkar Gargh
Year: 2012
Publisher: Research Journal of Chemistry and Environment, Vol 16 (1) March 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: Research Journal of Chemistry and Environment
Keywords: Benzyl phenyl ethers, Nicotinamide, N-chloronicotinamide, oxidation, kinetics
Abstract: Kinetics of oxidation of benzyl phenyl ethers [C6H5CH2O C6H4 - X], {X = H, o - Me, m-Me, P-Me, o-Cl and p-NO2} by N-chloronicotinamide (NCN) in aqueous acetic acid medium in the presence of hydrochloric acid and sodium perchlorate have been investigated by iodometric method. The oxidant, NCN is prepared by the chlorination of nicotinamide which is a biologically important compound. The observed rate of oxidation is first order in both [NCN] and [HCl] and zero order in [benzyl phenyl ethers]. An increase in the dielectric constant of the medium decreases the rate. Addition of nicotinamide, the reduction product of NCN, has slight retarding effect on the rate of oxidation. The reaction rate remains constant with the increase in [NaClO4]. The stoichiometry of the reactin is found to be 1:2. The reaction fails to induce polymerization of acrylonitrile under the experimental conditions employed. The kinetic and thermodynamic activation parameters Ea, ?H# , ?G# and ?S# have been calculated. The corresponding ester ahs been identified as the major product of oxidation.
Location: 241
Literature cited 1: None
Literature cited 2: None