46 research outputs found
Bioeconomic Analysis of Marine Fish Production in West Bengal
This paper presents the research findings of the study on the costal fisheries of Midnapore East, one of the costal districts of West Bengal by applying Surplus Production Model developed by Schaefer. We have estimated maximum sustainable yield (MSY), maximum economic yield (MEY) and open access yield (OAY). The Bioeconomic Model suggests the output corresponding to maximum sustainable yield is less than that of maximum economic yield, suggesting that allowing the fishermen at the point corresponding to optimum economic profit will violate the sustainability criteria. Open access yield (free access fishing) has been wasteful because it requires more effort and results in smaller catch than it would have been at MEY. So some regulatory mechanism in fishing effort is needed urgently to prevent over harvesting of stock. Keywords: Bio economics, Fishery, Sustainabilit
Microwave-assisted synthesis of ZnO-rGO core-shell nanorod hybrids with photo- and electro-catalytic activity
The unique two‐dimensional structure and surface chemistry of reduced graphene oxide (rGO) along with its high electrical conductivity can be exploited to modify the electrochemical properties of ZnO nanoparticles (NPs). ZnO‐rGO nanohybrids can be engineered in a simple new two‐step synthesis, which is both fast and energy‐efficient. The resulting hybrid materials show excellent electrocatalytic and photocatalytic activity. The structure and composition of the as‐prepared bare ZnO nanorods (NRs) and the ZnO‐rGO hybrids have been extensively characterised and the optical properties subsequently studied by UV‐Vis spectroscopy and photoluminescence (PL) spectroscopy (including decay life time measurements). The photocatalytic degradation of Rhodamine B (RhB) dye is enhanced using the ZnO‐rGO hybrids as compared to bare ZnO NRs. Further, potentiometry comparing ZnO and ZnO‐rGO electrodes reveals a featureless capacitive background for an Ar‐saturated solution whereas for an O 2 ‐saturated solution a well‐defined redox peak was observed using both electrodes. The change in reduction potential and significant increase in current density demonstrates that the hybrid core‐shell NRs possess remarkable electrocatalytic activity for the oxygen reduction reaction (ORR) as compared to NRs of ZnO alone
Florida’s Recycled Water Footprint: A Geospatial Analysis of Distribution (2009 and 2015)
Water shortages resulting from increased demand or reduced supply may be addressed, in part, by redirecting recycled water for irrigation, industrial reuse, groundwater recharge, and as effluent discharge returned to streams. Recycled water is an essential component of integrated water management and broader adoption of recycled water will increase water conservation in water-stressed coastal communities. This study examined spatial patterns of recycled water use in Florida in 2009 and 2015 to detect gaps in distribution, quantify temporal change, and identify potential areas for expansion. Databases of recycled water products and distribution centers for Florida in 2009 and 2015 were developed by combining the 2008 and 2012 Clean Water Needs Survey databases with Florida’s 2009 and 2015 Reuse Inventory databases, respectively. Florida increased recycled water production from 674.85 mgd in 2009 to 738.15 mgd in 2015, an increase of 63.30 mgd. The increase was primarily allocated to use in public access areas, groundwater recharge, and industrial reuse, all within the South Florida Water Management District (WMD). In particular, Miami was identified in 2009 as an area of opportunity for recycled water development, and by 2015 it had increased production and reduced the production gap. Overall, South Florida WMD had the largest increase in production of 44.38 mgd (69%), while Southwest Florida WMD decreased production of recycled water by 1.68 mgd, or 3%. Overall increase in use of recycled water may be related to higher demand due to increased population coupled with public programs and policy changes that promote recycled water use at both the municipal and individual level
Superparamagnetic iron oxide nanoparticle attachment on array of micro test tubes and microbeakers formed on p-type silicon substrate for biosensor applications
A uniformly distributed array of micro test tubes and microbeakers is formed on a p-type silicon substrate with tunable cross-section and distance of separation by anodic etching of the silicon wafer in N, N-dimethylformamide and hydrofluoric acid, which essentially leads to the formation of macroporous silicon templates. A reasonable control over the dimensions of the structures could be achieved by tailoring the formation parameters, primarily the wafer resistivity. For a micro test tube, the cross-section (i.e., the pore size) as well as the distance of separation between two adjacent test tubes (i.e., inter-pore distance) is typically approximately 1 μm, whereas, for a microbeaker the pore size exceeds 1.5 μm and the inter-pore distance could be less than 100 nm. We successfully synthesized superparamagnetic iron oxide nanoparticles (SPIONs), with average particle size approximately 20 nm and attached them on the porous silicon chip surface as well as on the pore walls. Such SPION-coated arrays of micro test tubes and microbeakers are potential candidates for biosensors because of the biocompatibility of both silicon and SPIONs. As acquisition of data via microarray is an essential attribute of high throughput bio-sensing, the proposed nanostructured array may be a promising step in this direction
Syntheses, crystal structures, magnetic properties and ESI-MS studies of a series of trinuclear Cu<sup>II</sup>M<sup>II</sup>Cu<sup>II</sup> compounds (M = Cu, Ni, Co, Fe, Mn, Zn)
Six trinuclear Cu(II)M(II)Cu(II) compounds (M = Cu, Ni, Co, Fe, Mn, Zn) derived from the Schiff base ligand, H(2)L (2 + 1 condensation product of salicylaldehyde and trans-1,2-diaminocyclohexane) are reported in this investigation. The composition of the metal complexes are [{Cu(II)L(ClO(4))}(2)Cu(II)(H(2)O)]·2H(2)O (1), [{Cu(II)L(ClO(4))}{Ni(II)(H(2)O)(2)}{Cu(II)L}]ClO(4)·CH(3)COCH(3) (2), [{Cu(II)L(ClO(4))}{Co(II)(CH(3)COCH(3))(H(2)O)}{Cu(II)L(CH(3)COCH(3))}]ClO(4) (3) and isomorphic [{Cu(II)L(ClO(4))}(2)M(II)(CH(3)OH)(2)] (4, M = Fe; 5, M = Mn; 6, M = Zn). Two copper(ii) ions in 1–6 occupy N(2)O(2) compartments of two L(2−) ligands, while the second metal ion occupies the O(phenoxo)(4) site provided by the two ligands, i.e., the two metal ions in both Cu(II)M(II) pairs are diphenoxo-bridged. Positive ESI-MS of 1–6 reveals some interesting features. Variable-temperature and variable-field magnetic studies reveal moderate or weak antiferromagnetic interactions in 1–6 with the following values of magnetic exchange integrals (H = −2JS(1)S(2) type): J(1) = −136.50 cm(−1) and J = 0.00 for the Cu(II)Cu(II)Cu(II) compound 1; J(1) = −22.16 cm(−1) and J = −1.97 cm(−1) for the Cu(II)Ni(II)Cu(II) compound 2; J(1) = −14.78 cm(−1) and J = −1.86 cm(−1) for the Cu(II)Co(II)Cu(II) compound 3; J(1) = −6.35 cm(−1) and J = −1.17 cm(−1) for the Cu(II)Fe(II)Cu(II) compound 4; J(1) = −6.02 cm(−1) and J = −1.70 cm(−1) for the Cu(II)Mn(II)Cu(II) compound 5; J = −2.25 cm(−1) for the Cu(II)Zn(II)Cu(II) compound 6 (J is between two Cu(II) in the N(2)O(2) compartments; J(1) is between Cu(II) and M(II) through a diphenoxo bridge)
Khesari (Lathyrus sativus L.), an ancient legume for future gain: An expedition collection from parts of West Bengal state of Eastern India
395-403Grasspea is one of the staple foods of the local people living in the eastern parts of India. An expedition was undertaken during March, 2020 to collect germplasm of grasspea in the lower-Gangetic riverine belt and coastal areas of West Bengal of eastern India lying between latitude 21.43-24.44°N and longitude 87.23-88.90°E. From the results of a structured questionnaire administered to grasspea farmers in 57 villages located in 96 local government areas, it appeared that grasspea is the primary winter pulse cultivated in this region. Large variability of germplasm exist, ranging from small to bold seed, early to late maturing types, moderate to the high biomass type of grasspea. Most of these landraces have been adopted over the years from neighbouring communities, but in a few instances, the varietal replacement was noted, which came either through the involvement of government departments or local seed dealers. The highest proportion of the accessions (52.38%) was collected from the Purba Medinipur district, and the lowest (19.05%) was from Paschim Medinipur. On-spot evaluation of morphological traits, variations was detected in the descriptor characteristics across the locations. A total of 21 accessions was collected and assessed on-spot for different characters, viz., the seed's size, shape, seed colour, taste and texture revealed significant variation. The implications of this survey results for grasspea improvement in India are discussed in the present study
Synthesis of graphene–transition metal oxide hybrid nanoparticles and their application in various fields
Single layer graphite, known as graphene, is an important material because of its unique two-dimensional structure, high conductivity, excellent electron mobility and high surface area. To explore the more prospective properties of graphene, graphene hybrids have been synthesised, where graphene has been integrated with other important nanoparticles (NPs). These graphene–NP hybrid structures are particularly interesting because after hybridisation they not only display the individual properties of graphene and the NPs, but also they exhibit further synergistic properties. Reduced graphene oxide (rGO), a graphene-like material, can be easily prepared by reduction of graphene oxide (GO) and therefore offers the possibility to fabricate a large variety of graphene–transition metal oxide (TMO) NP hybrids. These hybrid materials are promising alternatives to reduce the drawbacks of using only TMO NPs in various applications, such as anode materials in lithium ion batteries (LIBs), sensors, photocatalysts, removal of organic pollutants, etc. Recent studies have shown that a single graphene sheet (GS) has extraordinary electronic transport properties. One possible route to connecting those properties for application in electronics would be to prepare graphene-wrapped TMO NPs. In this critical review, we discuss the development of graphene–TMO hybrids with the detailed account of their synthesis. In addition, attention is given to the wide range of applications. This review covers the details of graphene–TMO hybrid materials and ends with a summary where an outlook on future perspectives to improve the properties of the hybrid materials in view of applications are outlined.publishe
Study of Optical and Magnetic Properties of Graphene-Wrapped ZnO Nanoparticle Hybrids
In this work, we
report a one-step method for the preparation of
graphene-wrapped zinc oxide (ZnO) nanoparticle (NP) (ZnO@G) hybrids.
These hybrids are characterized by transmission electron microscopy,
X-ray diffraction, Raman spectroscopy, optical absorption measurements,
photoluminescence (PL) emission spectroscopy, and <i>M</i>–<i>H</i> hysteresis measurements. All results reveal
that the ZnO NPs are entirely covered with graphene sheets. In the
PL spectra, the quenching of the band gap emission and the enhanced
green emission serve as evidence of the electron transfer from the
ZnO NPs to the graphene layer. The increase of the room-temperature
magnetization of the hybrid, compared to pure ZnO NPs, is due to the
increasing defect concentration. We suggest a band diagram model that
accounts for these observations. We present the simple wet-chemical
synthesis procedure to open a new way for the synthesis of NP–graphene
hybrid systems having magnetic properties giving the large manifold
potential application
Evaluation of the conspicuous EPL matches for sponsorships using data envelopment analysis
The analysis of games data, especially football is a thrilling field. Data Envelopment Analysis (DEA) was applied to find out most conspicuous matches out of 288 matches in the EPL 2019-20 using various inputs and various outputs variables. Total Fouls, Total Yellow Cards, Total Red Cards are taken as inputs variables. Number of Goals Scored, Total Number of Shots, Total Shots on target, Total Corners, Total Plays in Opponent Final Third, Market Value of Squad are taken as outputs variables. There are six matches have been found as most conspicuous. These matches are 41st (Liverpool Vs Newcastle United), 53rd (Manchester City Vs Watford), 68th (Everton Vs Manchester City), 91st (Leicester City Vs Southampton FC), 131st (Manchester City Vs Newcastle United) and 270th (Liverpool Vs West Ham). These results not only show the most conspicuous matches but also help to make financial decision for sponsorships. Most attractive matches bring more spectators.