A multivariate statistical study with a factor analysis of recent planktonic foraminiferal distribution in the Coromandel Coast of India

A study of planktonic foraminiferal assemblages from 19 stations in the neritic and oceanic regions off the Coromandel Coast, Bay of Bengal has been made using a multivariate statistical method termed as factor analysis. On the basis of abundance, 17 foraminiferal species, species were clustered into 5 groups with row normalisation and varimax rotation for Q-mode factor analysis. The 19 stations were also grouped into 5 groups with only 2 groups statistically significant using column normalisation and varimax rotation for R-mode analysis. This assemblage grouping method is suitable because groups of species/stations can explain the maximum amount of variation in them in relation to prevailing environmental conditions in the area of study

The Complications Involved in Processing Graphite Ore from Tapaskonda area, East Godavari district, Andhra Pradesh

Graphite is one of the most versatile non-metallic minerals because of its diverse properties. To make the graphite suitable to any group of industry need special type of treatment or processing of the ore. Efforts are made to study the feasibility of economic processing to get a commercial grade of graphite to suit the specific industrial uses and at the same time recovering the tungsten values from the identified sources are in progress . The various complications and implications are discussed. Burugubanda graphite deposit (SW) zone does not pose any difficulty, but Tapaskonda graphite (NE) zone posses complications during grinding to coarse medium and fine sizes and recovery of tungsten values at various stages by suitable processes like jigging , tabling, hydrocyclones. The gravity recovery is maximum in fine sizes -200 mesh giving a grade more than 90% F C and 88-90% of recovery. During comminution process and size sepe-ration the complications are explained . After crossing all the complications we could achieve a final grade of graphite assaying 90 % F C. with 85% of recovery. After obtaining preconcentrates of WO3 we could finally achieve the 60% WO3 marketable grade is 65% WO,. Further studies are in progress to have a detailed mineralogical, parti- culate and geochemical studies of tungsten and graphite and other associated minerals so that we can suggest a suitable method to have a better grade of tungsten conce- ntrate considering the large promising potentialities of the are in Andhra Pradesh

Foraminifera from beach sands along Saurashtra coast, north-west India

One hundred seven foraminifera1 species have been identified and studied quantitatively in regard to their relative abundance in sand samples from 13 stations along the Saurashtra coast. This study has shown that Ammonia beccarii (Linn6) variant is the dominant and most widely distributed species of the coast. Ammonia tepida, Asterorotalia dentata, Hanzawaia asterizans and Pararotalia minuta are the other abundant species of the fauna. The fauna is dominated by species of Rotaliina followed by Miliolina, Textulariina, Globigerinina, Lagenina and Robertinina. Furthermore, it shows affinity with that of Indo-Pacific faunal province. Also, the relationship between the abundance of Foraminifera and the median grain size of the sand is discussed

Studies on lead-zinc mineralization in Karempudi area, Guntur District, Andhra Pradesh

The geological formations near Karempudi area in Guntur District of Andhra Pradesh (Lat. 16°20' and 16°26'; Long. 79° 38'40" and 79°45') consist of slaty shales of Cumbum, Irlakonda quartzites, Kolumnala slates and shales with intercalations of siliceous dolomitic limestones and Sreesailam quartzites of Krishna Series, forming a perfect conformable sequence, all the formations striking N.E.-S.W. and dipping on average 25°S.E. The Srisailam quartzites are overlaid unconformably by Palnad limestones (Narjis) of Jammalamadugu stage of Kurnool Series with a constant dip of 8-12° in the same direction. The Krishna Series were subjected to local but intense structural disturbances resulting in an overfold. Subsequent to the overfolding, lead mineralization has taken place in dolomitic limestones. The lead-zinc minerals of Karempudi consist of Galena, Sphalerite, Jamesonite, Tetrahedrite as primary minerals, and Anglesite as secondary mineral; there is association of chalcopyrite with Sphalerite. The textures are due to replacement and unmixing. The paragenetic sequence of the minerals is established to be sphalerite, chalcopyrite, galena, jamesonite, tetrahedrite and anglesite. Correlation of field to laboratory studies revealed that the minerals are of hydrothermal (hypogene) origin. The structural and lithological favourability and controlling of the mineralisation are also explained. Anglesite owes its origin to the oxidation of galena due to air-water processes. The mineralization is surmised to have taken place in Pre-Palnads and Post-Krishna times

2D Fem Analysis of Earth and Rockfill Dams under Seismic Condition

The paper pertains to the seismic analysis of earth and rockfill dams with the aid of MSC_ Nastran (Windows) package. After validation, the package has been used to investigate the dynamic response of Tehri Dam, located in the seismically active region of Himalayas. A 2D FEM analysis is adopted wherein the dam has been modeled as a linear, elastic, non-homogeneous material. The base acceleration data of the Bhuj Earthquake has been used as an input motion. Effect of Poisson’s ratio and the ratio of the canyon length to the height of the dam has been investigated and is reported. Acceleration-time histories reveal that the maximum acceleration occurs at the crest of the dam, and decreases towards the bottom of the dam. Displacement-time histories reveal that the vertical displacement at any locations of the dam is negligibly small compared to the horizontal displacement. The shear stresses evaluated displays a maximum and minimum magnitude at the shell and core of the dam respectively. Velocity-time history shows a maximum velocity in the forward direction at the crest of the dam, while in the reverse direction, the same is experienced by the shell and the core of the dam supplemented by a noticeable phase difference

Detection of Ricin in Water Samples using DisposableScreen-printed Electrodes

Ricin is a highly toxic plant toxin, which is extracted from the beans of the castor plant,Ricinus communis. Ricin is thousand times more poisonous than cyanide and thirty times morepotent than nerve gases. The toxin (ricin) could be used to contaminate food or water, causingpanic. Attempts were made for the detection of ricin in water samples by utilising amperometricimmunosensors. Single-use screen-printed electrodes were made using polystyrene and graphite.These electrodes were tested  for  their ability  to detect 1-naphthol which is the product of thereaction between 1-naphthyl phosphate and the enzyme alkaline phosphatase conjugate. Anindirect enzyme-linked immunosorbent assay (ELISA) system was used to detect ricin. First,ricin antigen was incubated on the screen-printed electrode. This was followed by blocking withBSA and incubation with antibody raised against ricin in rabbit. The last step wass the incubationwith anti-antibody of rabbit conjugated to enzyme alkaline phosphatase. This electrode is insertedin an electrochemical cell containing diethanolamine buffer and a potential of 0.4 V wrt referenceelectrode (Ag/AgCl) was applied  using a potentiostat.  Various experiments were carried out  foroptimising the conditions like substrate concentration, amount of antibody raised against ricin,anti-antibody alkaline phosphatase conjugate, and blocking agents. It was found that the responseof amperometric sensor is proportional to the logarithmic of ricin concentration from 100 ng/mlto 3200 ng/ml.  Using traditional methods, it is possible to detect ricin concentration up to 300ng/ml in 18 h, while with amperometric immunosensor, one can detect ricin as low as 40 ng/mlwithin 90 min. The details of making the screen-printed electrodes, characterisation, optimisationof various conditions for the highest sensitivity have been discussed

CCD photometry in VRI bands of the galactic cluster NGC 2818

The open cluster NGC 2818 containing a planetary nebula has been observed in VRI bands using the CCD system at prime focus of the 2.3- metre Vainu Bappu Telescope. The study extending to stars V ~ 21 magnitude establishes the distance modulus as (m-M)0 = 12.9 ±0.1 for the cluster. Based on the fitting of theoretical isochrones computed for solar metallicity, an age of 5(±1) × 108 years has been assigned to the cluster. Association of the planetary nebula with the cluster indicates that the progenitor mass of the planetary nebula on the main sequence is ≥2.5M⊙