Growth and survival of the Indian Pearl oyster (Pinctada fucata) in Kakinada Bay

Kakinada Bay which has a total spread of 146 sq.km. area has diverse moUuscan resources, especially bivalves and gastropods. Several workers have studied in detail, the molluscan resources of the Bay and their fishery characteristics. The Bay also harbuors a population of resident pearl oyster, Pinctada chemnitzii towards its eastern side near Hope Island. But Pinctada fucata is an exogenous species as far as Kakinada Bay is concerned

Mixing in the surface waters of the western Bay of Bengal using 228Ra and 226Ra

228Ra and 226Ra have been measured in the surface waters of the western Bay of Bengal during five cruises conducted between 1988 and 1999. The ranges and mean (given in brackets) concentrations for 228Ra and 226Ra are 6.8-42.1 (17.8 ± 7.9) dpm/100 kg and 6.0-16.7 (9.2 ± 2.2) dpm/ 100 kg, respectively. (228Ra/226Ra) Activity Ratio (henceforth denoted as [228/226]) ranges from 0.8 to 3.4 with a mean of 1.9 ± 0.5. Both 228Ra and 226Ra show inverse correlation with salinity, the former much stronger. A surface 2-D diffusion-advection model is used with a new approach. A simple bivariate function, C(x,y) = C0e-Ax·e-By where C0, A and B are constants, is fitted to the whole 228Ra and 226Ra data C(x,y). Substituting C(x,y) in the two-dimensional steady-state diffusion equation of Ra, the estimated values of the constants A and B can be related to eddy diffusivities and advection velocities in the zonal (x) and meridional (y) directions. From this relationship, the horizontal eddy diffusivities in the zonal and meridional directions are inferred to be 1.3 × 107 and 2.1 × 108 cm2s-1, respectively in the absence of advection terms. Similarly, neglecting the influence of diffusion, one can estimate the advection velocities, wx and wy in the zonal and meridional directions, as 0.2 and 1.1 cm s-1, respectively. The model-fit values C(x,y) of 228Ra concentrations are in good agreement with the measured values except in regions showing exceptionally high and low values. Incorporating both the advection rates and eddy diffusivities into the equation, it is found that increasing advection velocities depending on the direction can decrease or increase the eddy diffusivities and that such changes are more effective in the meridional direction compared to zonal direction in the region of study. On the whole, 228Ra appears a good tracer to derive rates of mixing between low salinity waters in the north and their high salinity southern counterparts of the western Bay of Bengal. The eddy diffusivities, Kx and Ky (without advection) derived for the Bay of Bengal are higher by about an order of magnitude than the ones similarly obtained for the Arabian Sea. This is not unexpected due to the turbulent conditions prevailing in the Bay of Bengal for most of the year

Stabilisation of Red Phosphorus to Prevent Moisture Absorptionand Suppression of Phosphine Release

Red phosphorus (RP) is an essential ingredient to generate smoke for multi-spectralobscuration and is receiving wide attention throughout the world for military applications.However, oxidation of phosphorus occurs in moist air resulting in the formation of variousphosphorus acids and subsequently the evolution of the toxic gas, phosphine (PH3), even inthe sealed systems. Entrapped moisture leads to deterioration of the stores. The commercial-RPat ambient temperature and 95 per cent  RH conditions indicates 15 per cent  moisture absorptionand 13 per cent acidity development with the generation of more than 100 ppm of phosphinegas. Efforts were made to overcome this problem by suppressing acid formation. The technologyadopted was: (i) use of stabiliser, and (ii) doping stabiliser-coated particles with polymericsubstance. The aim to use metal oxide as stabiliser was to neutralise the phosphorus acids,which are catalysing the phosphine generation. MgO due to its basic nature seems to be fasterthan amphoteric Al2O3, in removing the acid from site of reaction, thus suppressing the phosphinerelease effectively. Though MgCO3 as stabiliser suppresses moisture absorption and aciditydevelopment, phosphine release is not controlled effectively. Study of RP coated with thesematerials independently and monitoring them at different RH conditions indicated superiorityof MgO in suppressing acidity and phosphine formation

Are contrastive explanations useful?

Funding Information: Supported by EPSRC DTP Grant Number EP/N509814/1Peer reviewedPublisher PD

Smoke Composition to Disseminate Capsaicinoids in Atmosphere as Sensory Irritant

Dissemination of sensory irritants in the atmosphere with the help of an evaporating mixtureis adopted. Experiments were carried out to find an alternative sensory irritant which is moreirritating and less toxic than the existing sensory irritating agents and originating from a naturalsource. Extract of red pepper, the oleoresin, is less toxic than the existing sensory irritants andis analysed for its constituents. Thermal studies of capsaicin and the composition indicate thatthe composition ignites at 190 °C whereas capsaicinoids boil at 214 °C. Lactose-KClO3 reactionwas found to release sufficient thermal energy to evaporate capsaicinoids into the atmospherewithout degeneration. The compositions are both friction and impact insensitive. Thedissemination of capsaicinoids into the atmosphere was confirmed using HPLC technique

Atlas.txt : Exploring Lingusitic Grounding Techniques for Communicating Spatial Information to Blind Users

Peer reviewedPostprin

Cephalopod fishery at Kakinada along the east coast of India: Resource characteristics and stock assessment of Loligo duvauceli

At Kakinada along the east coast of India, cephalopods were exploited by trawls. Fishery occurred round the year with peak during August-October. Peak abundance and fishery of cuttlefishes coincides with this period, whereas for squids it is during March-May. Cephalopod production continued to increase initially with fishing effort, until 1995, but declined thereafter despite increased fishing effort and expansion of fishing to deeper waters. Fishery, growth, mortality, recruitment pattern and exploitation rates of Loligo duvauceli were studied

Fishery, population characteristics and stock assessment of cuttlefishes, Sepia aculeata and Sepia pharaonis at Kakinada along the east coast of India

Cuttlefishes were exploited exclusively by trawls along the coast. Growth, recruitment, mortality and exploitation rates of Sepia aculeata and Sepia pharaonis were studied. Fishery of the former was supported mainly by zero year and the latter by zero and one + age groups. Both attain sexual maturity during the first year itself and spawn during August-March with peak during November-December. Natural mortality of S.aculeata was 2.22, fishing mortality 2.34 and total mortality 4.56

Radiometric Screening of Red Phosphorus Smoke for its Obscuration Characteristics

Red phosphorus and potassium nitrate-based compositions exhibit favorable smoke screenformation with high obscuration characteristics at low oxidiser content. The rapid vaporisationof excess red phosphorus at higher flame temperature leads to quick aerodispersion. Theobscuration characteristics are due to formation of P2O5 and subsequent reaction with moisture/humidity in the atmosphere. Obscuration increases with increasing humidity. Extinction coefficient,the shadow cast per unit mass of the composition, is higher in visible and comparatively lowerin far infrared

Solar control of Southwest monsoon on centennial timescales

Solar forcing is proposed to be a major governing factor for the southwest monsoon (SWM) strength during the Holocene. The southeastern Arabian Sea is significantly affected by monsoon run-off and is an ideal testing ground. We analysed stable oxygen isotopic composition (δ18O) of three species of planktonic foraminifera (Globigerinoides ruber, Gs. sacculifer and Globarotalia menardii) with high time-resolution (~50 yrs) in a sediment core raised from the region, and documented past variations in SWM precipitation. High-resolution isotopic and spectral analyses show that solar forcing indeed played a major role in governing the past variations in SWM precipitation on centennial timescales