2,135 research outputs found

    Toxicity of four therapeutic compounds to fry of Indian major carps

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    Toxicity of four therapeutic compounds: sodium chloride, potassium permanganate, potassium dichromate and acriflavine to fry of Catla calla, Labeo rohita and Cirrhinus mrigala was tested. Bioassays were conducted in 5 and 10 liters glass jars in the laboratory for periods of 24-48 hrs. at temperatures of 26Ā° and 32Ā°C. LC 50 values of the chemicals were in the ranges of 5500 to 7500 ppm, 37.5 to 48 ppm, 92.5 to 125 ppm and 47.5 to 80 ppm respectively. The results obtained are of value in evolving cheap control methods against some common fish diseases. Sodium chloride and acriflavine can be widely used for chemotherapy and potassium dichromate is preferable to potassium permanganate for prophylaxis

    Evaluation of water quality of Mundeswari River in eastern India: a water quality index (WQI) based approach

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    The Mundeswari River is the western distributary of the Damodar River system in eastern India. The water of this river is extensively used for domestic purposes and agricultural irrigation. This study aimed to evaluate the spatial and temporal water quality variation of the Mundeswari River and assess the water quality status of this river using the Canadian Council of Ministers of the Environment Water Quality Index (CCME-WQI). Water quality was monitored monthly at four selected sampling stations (M1, M2, M3, and M4) during 2020-2022, considering twelve selected water quality indicators. The obtained water quality data were analysed using different statistical techniques. Water quality at different monitoring stations was appraised through the use of CCME-WQI. The results revealed that the overall water quality of most of the monitoring stations based on CCME-WQI values was ā€œmarginal.ā€ The highest WQI value (82.01) was observed at M1, and the lowest WQI (41.24) was recorded at M3. One-way ANOVA indicated a statistically significant difference in WQI values between sampling sites (P <0.05). The water quality of the M3 sampling station was found to be in degraded condition throughout the study period. Cluster analysis from the perspective of WQI values revealed two distinct clusters of the sampling stations. Substantial seasonal variation in water quality was also observed. This river had putrid water quality during the pre-monsoon period, and relatively better water quality was evident after the monsoon. This study revealed that the water of the Mundeswari River is utterly unsafe for human consumption and it requires significant treatments before it can be safely used for domestic purposes like cooking, washing etc

    Synthesis of Corrosion-resistant Nanocrystalline Nickle-copper Alloy Coatings by Pulse-plating Technique

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    Bright and smooth nanocrystalline Monel-type Ni-Cu alloy gets deposited from complex citrate electrolyte by pulse electrolysis. Transmission electron microscopy studies have revealedthat the deposited Ni-Cu alloy was nanocrystalline in nature and it comprised a two-phase (fcc+Ll,) mixture. The presence of twins could be seen in the nanocrystals. The Ni-Cu alloysprepared by pulse electrolysis were finer grained (- 2.5-28.5 nm) than those deposited by direct current method. Nelson-Riley function has been used to calculate the lattice parameters for both the pulse current-plated and direct current-plated alloys from x-ray diffraction analysis. The microhardness values for pulse current-plated alloys were higher than for the direct currentplated alloys. The internal stresses of both the pulse current-deposited and the direct currentdeposited alloys have also been measured; the values were lower for pulse current-plated alloys. Potentiodynamic polarisation studies were carried out in aerated and deaerated neutral 3.0 Wt per cent NaCl solution and instantaneous corrosion current density of the plated alloy was determined and compared with the Monel-400 alloy. It was found that nanocrystalline pulse current-N,-35 8 Wt p;r cent copper alloy uxh~bitedlo wer instantaneous value of corros~onc urrent densirv than that of soeclrnens with direct current method and Monel-400 allov The d~ssolut~on ~ ~~~~-~ behaviour ofthe deposited nanocrystalline material was found to be more like general corrosion rather than localised corrosion as in the case of Monel-400 alloy

    Cable Design for FAIR SIS 300

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    GSI, Darmstadt is preparing to build FAIR (Facility for Antiproton and Ion Research) which include SIS 300, a 300T - m fast-ramping heavy ion synchrotron. Dipoles for this ring will be 2.9 m long, producing 6 T over a 100 mm coil aperture and ramped at 1 T/s. The cable for these dipoles must have low losses and produce acceptable field distortions during the fast ramp. We plan to achieve this objective by using fine (~ 3 mum) filaments of NbTi in a wire with an interfilamentary matrix of CuMn to reduce proximity coupling and increase the transverse resistivity. The Rutherford cable have a thin stainless steel core and the wires will be coated with SnAg solder which has been oxidized, using a recipe similar to that developed at CERN, to increase the adjacent strand resistance Ra. Measurements of crossover strand resistance Re and Ra in cored cable with oxidized SnAg coating will be presented, together with data on critical current, persistent current magnetization and eddy current coupling in a wire with ultra fine filaments and a CuMn matrix in the interfilamentary region of the wire. These data will be used to predict losses and field distortion in the SIS 300 dipole and optimize the final design of cable for FAIR

    A record production from an integrated farming system utilising sewage enriched water

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    The results of experiments conducted on a pond dyke (655mĀ²) in the Wastewater Aquaculture Division of the Central Institute of Freshwater Aquaculture, Rahara, during 1992-93 for maximising production through optimum utilisation of resources are communicated. Round the year intensive cultivation of okra (Abelmoschus esculentus), amaranth (Amaranthus gangeticus and A. viridus), water-bind weed (Ipomea aquatica), Indian spinach (Basella rubra), radish (Raphanus sativum), amaranth (Amaranthus viridis), cauliflower (Brassica oleracia var. votrytis), cabbage (Brassica oleracia var. capitota) and papaya (Carica papaya) was undertaken using the treated sewage water from fish ponds for irrigation. The pond dyke yielded 5,626.5 kg vegetable which worked out to 85.9 tons per ha per year. Multiple cropping with these vegetables excluding papaya on a 460 mĀ² dyke recorded a production of 4,926.5 kg at the rate of 107.1t per ha/yr. An improved yearly net return of about 35% over investment could be achieved through the selection of highly productive and pest resistant vegetable crops of longer duration for integration into the system. Introduction of this type of integrated farming would enhance the overall productivity and returns from farming

    Utilisation of vegetable leaves for carp production

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    The results of two sets of experiments on mono-culture of grass carp (Ctenopharyngodon idella) and mixed culture of carps (grass carp 50 : catla 20 : rohu 15 : mrigal 15) fed exclusively with vegetable leaves are reported. The experiments were conducted with two replicates each in 0.02 ha ponds of Wastewater Aquaculture Division of the Central Institute of Freshwater Aquaculture, Rahara during 1991-93. Monoculture of grass carp stocked at 1000/ha demonstrated an average net production of 21.0 kg/ 0.02 ha/8 months (1501 kg/ha/yr). Mixed culture of carps stocked at 5000 /ha recorded an average net production of 22.5 kg/0.02 ha/8 months (1903.7 kg/ha/yr). Field studies revealed that water bind weed (Ipomoea aquatica) is the most preferred feed of grass carp amongst vegetable leaves followed by amaranths (Amaranthus gangeticus and Amaranthus viridis), cauliflower (Brassica oleracia var. votrytis) and cabbage (Brassica oleracia var. capitata) leaves. Through selection of highly productive leaf vegetables and suitable crop planning on fallow fish pond dykes, round the year feeding programme of grass carp has been explored. Recycling of sewage effluent for vegetable production and utilisation of vegetable leaves for fish production is considered an ideal way of integrated resource management for low cost production

    Parameter Estimation from Near Stall Flight Data using Conventional and Neural-based Methods

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    The current research paper is an endeavour to estimate the parameters from near stall flight data of manned and unmanned research flight vehicles using conventional and neural based methods. For an aircraft undergoing stall, the aerodynamic model at these high angles of attack becomes non linear due to the influence of unsteady, transient and flow separation phenomena. In order to address these issues the Kirchhoffā€™s flow separation theory was used to incorporate the nonlinearity in the aerodynamic model in terms of flow separation point and stall characteristic parameters. The classical Maximum Likelihood (MLE) method and Neural Gauss-Newton (NGN) method have been employed to estimate the nonlinear parameters of two manned and one unmanned research aircrafts. The estimated static stall parameter and the break point, for the flight vehicles under consideration, were observed to be consistent from both the methods. Moreover the efficacy of the methods is also evident from the consistent estimates of post stall hysteresis time constant. It can also be inferred that the considered quasi steady model is able to adequately capture the drag and pitching moment coefficients in the post stall regime. The confidence in these estimates have been significantly enhanced with the observed lower values of Cramer-Rao bounds. Further the estimated nonlinear parameters were validated by performing a proof of match exercise for the considered flight vehicles. Interestingly the NGN method, which doesnā€™t involve solving equations of motion, was able to perform on a par with the MLE method

    Design, Testing, and Realisation of a Medium Size Aerostat Envelope

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    The design, testing and realisation aspects during the development of a medium size aerostat envelope in theĀ present work. The payload capacity of this aerostat is 300 kg at 1 km above mean sea level. The aerostat envelopeĀ is the aerodynamically shaped fabric enclosure part of the aerostat which generally uses helium for lifting usefulĀ payloads to a specified height. The envelope volume estimation technique is discussed which provides the basis forĀ sizing. The design, material selection, testing and realisation aspects of this aerostat envelope are also discussed.Ā The empirical formulas and finite element analysis are used to estimate the aerodynamic, structural and other designĀ related parameters of the aerostat. Equilibrium studies are then explained for balancing forces and moments in staticĀ conditions. The tether profile estimation technique is discussed to estimate blow by distance and tether length. AĀ comparison of estimated and measured performance parameters during trials has also been discussed

    Reserve Estimation of Proposed Opencast Mine of Ramnagore Colliery

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    As jhama and burnt coal are saleable items with sizeable demand in different small and medium scale industries, the management of Ramnagore Colliery of Steel Authority of India Ltd. (SAIL) has decided to mine jhama, burnt coal, coal and the strata of jhama intruded by mica peridotite from Salanpur D-2, Salanpur D-1 and Salanpur C seams in a block near north-eastern boundary of the colliery, covering a total area of around 22.01 hectare. The proposed mine is located in Ramnagore part of Indikatta-Ramnagore Block on the eastern bank of the Barakar River in Raniganj Coalfield. This paper describes the methodology of reserve estimation along with estimation of pit life, waste and stripping ratio. Geological report by Central Mine Planning & Design Institute Ltd. (CMPDI) in 1995 forms the basis of the geological information of the area. The report indicates that due to pyrolysis, the seams have been transformed into a combination of layers of jhama, burnt coal, coal and the layers of jhama intruded by mica peridotite. Of the 15 boreholes in and around the proposed opencast mining site, lithologs of only 13 boreholes are available with the mine management and only 8 boreholes fall inside the proposed mining area. The classification of seams in the lithology of the boreholes is neither very clear, nor very convincing. The results indicate that it would be much more economic to mine the site en bloc than to mine Western and Eastern blocks separately leaving a 90 m wide barrier in between them to protect the existing high voltage electric supply line. In isolation, the West Block, which covers nearly two-third of the whole site, will run for two-and-half years, producing a little more than 40% of the total mineable reserve of the whole site and generating 63% of the total waste likely to be generated had the whole site been mined as one. Overall stripping ratio of the Western Block will be 8.36 M3/t, i.e. nearly one and half times of the stripping ratio of 5.47 M3/t, expected for the mining of the whole site in one go. The Eastern block that covers only about 15% of the whole site will result in production for only two months. The production will comprise not even 3% of the total mineable reserve in the whole site, that too with a high oveall stripping ratio of 12.82 M3/t. On the other hand, if the whole site is mined en bloc, the mine is likely to run for six years yielding more than 0.7 million tonne of minerals (coal, burnt coal and jhama together) with a stripping ratio of 5.47 M3/t approximately
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