SiO2 coating of silver nanoparticles by photoinduced chemical vapor deposition.

Gas-phase silver nanoparticles were coated with silicon dioxide (SiO2) by photoinduced chemical vapor deposition (photo-CVD). Silver nanoparticles, produced by inert gas condensation, and a SiO2 precursor, tetraethylorthosilicate (TEOS), were exposed to vacuum ultraviolet (VUV) radiation at atmospheric pressure and varying temperatures. The VUV photons dissociate the TEOS precursor, initiating a chemical reaction that forms SiO2 coatings on the particle surfaces. Coating thicknesses were measured for a variety of operation parameters using tandem differential mobility analysis and transmission electron microscopy. The chemical composition of the particle coatings was analyzed using energy dispersive x-ray spectrometry and Fourier transform infrared spectroscopy. The highest purity films were produced at 300-400 degrees C with low flow rates of additional oxygen. The photo-CVD coating technique was shown to effectively coat nanoparticles and limit core particle agglomeration at concentrations up to 10(7) particles cm(-3).

Mass breeding of silver carp in a cement cistern with crude H.C.G.

The paper presents a resume on experiments carried on mass breeding of the silver carp Hypophthalmichthys molitrix in a cement cistern through administration of crude human chorionic gonadotropin. The experiments proves that human chorionic gonadotropin (H.C.G.) can be used for mass breeding of the fish in simple enclosures, with facilities of some input and output of water and a dose of 5 mg/kg and 18 mg/kg of body weight, for males and females respectively are required for the purpose. Observations were made by using pituitary glands in similar way. For successful breeding of about 80 kg female together, the expenditure towards cost of pituitary gland and H.C.G. are respectively 275 and 117 Rs.

On the production and nutritive value of fish meal from Silver belly (Leiognathus spp.) landings at Rameswaram

Silver belly (Leiognathus Spp.) forms a major fishery in recent years in the Rameswaram island but fetches for the fishermen very low prices ranging from Rs. 0.03 to 0.12/Kg only, there being practically no demand for the fish. The possibilities of utilizing this cheap fish are discussed and the processing method described. During the glut season the cost of production of Silver belly fish meal works out to competitive prices of Rs. 500 to 700/ton. The silver belly fish meal is of high quality with good protein content averaging 57.71% in commercial samples and 61.90% in laboratory samples and with a high pepsin digestibility of 90.0% to 92.5%. The essential amino acid composition of the Silver belly fish meal compares very favorably with other round fish meals, with high contents of lysine, leucine, arginine, isoleucine, methionine, phenyl alanine, threonine and valine. Since there is good demand for fish meal as poultry and cattle food both in the internal and external markets, there is good scope for large scale production and sale of fish meal.

Studies on the storage characteristics of Silver pomfret (Pampus argentus) transported to Bombay

An investigation on the quality of pomfrets transported to Bombay from Gujarat coast and its subsequent changes during storage at room temperature and low temperature were carried out and the results reported. The pomfrets transported in boats having insulated holds were in better condition than those having non insulated holds. In general, the transported fish can be effectively stored in ice for 2 days, while the fish is in acceptable condition up to 4 days.

Polyculture of gulsha (Mystus cavasius Ham.) with rajpunti (Puntius gonionotus Bleeker) and silver carp (Hypophthalmichthys molitrix Val.) in earthen ponds

Culture of gulsha (Mystus cavasius) with rajpunti (Puntius gonionotus) and silver carp ( Hypophthalmichthys molitrix) was undertaken to assess the growth and production potential of these species under polyculture system. Fingerlings of gulsha, rajpunti and silver carp were stocked at a density of 18.000, 10.000 and 4.000/ha respectively. Two treatments were tested in this experiment. Treatment-I was conducted with rice bran and mustard oil cake and treatment-II with rice bran and duck weed. All the ponds were fertilized with urea and TSP at fortnightly intervals. After six months' rearing, the gross production was estimated to be 3,582 and 3,125 kg/ha from treatment-I and treatment-II respectively. Total yield showed non-significant differences (P>0.05) between the treatments.

Impacts of Thai silver barb (Puntius gonionotus Bleeker) inclusion in the polyculture of carps

The impact of inclusion of Thai silver barb, Puntius gonionotus (Bleeker) in the polyculture with two major Indian carps viz., Labeo rohita, Catla catla and common carp Cyprinus carpio has been studied in seasonal ponds for 115 days. The presence of silver barb decreased the growth of Indian carps while increased that of common carp. A significantly higher (P<0.05) fish yield (1793.65 Kg/ha/yr) was observed in the four species polyculture system containing silver barb when the combined yield of all species was compared.