488 research outputs found
Rough triggerfish, Canthidermis maculata from Gujarat coast
A specimen of the Rough triggerfish,
Canthidermis maculata (Bloch, 1786) was landed
by a multiday trawler on 25th November 2015 at
Mangrol Fisheries Harbour, Gujarat. The specimen
was brownish grey in colour with characteristic
white spots all over the body including the head. It
measured 309 mm and 256 mm in Total length and
Standard length respectively with a weight of 580 g
(Fig. 1). The fish is usually found in areas having
sandy, muddy or rocky bottoms at a depth range of
50-100 m and is reported from the Western Indian
Ocean
Dynamics of vegetative morphomatrix, productivity and economics of NA 7 aonla (Emblica officinalis) in different planting systems under rainfed conditions
A field experiment was conducted to determine the effects of different planting systems and densities on plant growth and their relation to yield and quality attributes of NA 7 aonla (Emblica officinalis Gaertn) during the years 2011-2013 under rainfed hot semi- arid ecosystem of western India. The present study contained 5 planting systems as treatments namely, square, hedgerow, double hedge row, cluster and paired system. Different planting systems significantly influenced the vegetative growth, yield and quality of fruits during both the years of experimentation. The highest plant height was noted in double hedgerow system (7.80 m) and the lowest in paired system (7.08 m). Consequently, the rootstock (59.82cm), scion girth (58.38 cm) and plant spread (6.99 cm) was measured maximum in square system of planting. However, these parameters were measured the lowest in double hedgerow followed by hedgerow and cluster planting systems. Result of study revealed that the mean yield/plant (110.24 kg) was recorded the highest in square but the yield/ha were recorded maximum in double hedgerow (225.90 q) followed by hedgerow (202.65 q) and cluster (170.37 q). During the experimentation, a considerable difference in yield over previous year was observed among the different planting systems. An increase in yield over square system by the rest of the system ranged between 83.8% - 132.39% being highest in double hedgerow and lowest in paired system, whereas per cent increase in yield in double hedgerow over other systems ranged between 26.44-132.39 being the maximum and minimum upon square and hedgerow systems of planting, respectively. There were significant differences amongst different planting system with regards to fruit physical and quality attributes. Among the different planting systems, the square system exhibited better values for physical qualities, whereas chemical attributes like TSS, total sugar, vitamin C and total phenols were observed maximum in double hedgerow planting system. The net economic return was computed with double hedgerow (₹192 270.00 and ₹ 243 035.00) followed by hedgerow (₹ 150 800.00 and ₹195 650) and it was minimum in square (₹ 83 950.00 and ₹ 107 605.00) system of planting
Measurement of (n,γ) reaction cross section of 186W-isotope at neutron energy of 20.02±0.58 MeV
The cross-section of 186W(n,γ)187W reaction has been measured at an average neutron energy of 20.02±0.58 MeV by using activation technique. The 27Al(n,α)24Na and 115In(n,n´)115mIn reactions have been used for absolute neutron flux measurement. Theoretically the reaction cross-sections have been calculated by using the TALYS-1.9 code. The results from the present work and the EXFOR based literature data have been compared with the evaluated data and calculated data from TALYS-1.9 code
Measurement of (n,γ) reaction cross section of 186W-isotope at neutron energy of 20.02±0.58 MeV
392-396The cross-section of 186W(n,γ)187W reaction has been measured at an average neutron energy of 20.02±0.58 MeV by using activation technique. The 27Al(n,α)24Na and 115In(n,n´)115mIn reactions have been used for absolute neutron flux measurement. Theoretically the reaction cross-sections have been calculated by using the TALYS-1.9 code. The results from the present work and the EXFOR based literature data have been compared with the evaluated data and calculated data from TALYS-1.9 code
Measurements of 181Ta(n,2n)180Ta reaction cross-section at the neutron energy of 14.78 MeV
The cross-section of the 181Ta(n,2n)180Ta reaction has been measured with respect to the 197Au(n,2n)196Au monitor reaction at the incident neutron energy of 14.78± 0.20 MeV, using neutron activation analysis and off-line γ-ray spectrometric technique. The present measurement has been done at the energy where discrepant measured results are available in the EXFOR data library. The result has been compared with evaluated data libraries JEFF-3.3 and ENDF/B-VII.1. The present result has also been supported by theoretical predictions of nuclear model code TALYS1.8 and TALYS-1.9. The uncertainty and the correlations among the measured cross-section has been studied using co-variance analysis
Oxy-functionalization of olefins with neat and heterogenized binuclear V(IV)O and Fe(II) complexes: effect of steric hindrance on product selectivity and output in homogeneous and heterogeneous phase
Neat {[VO(sal2bz)]2; [Fe(sal2bz)(H2O)2]2·2H2O} and zeolite-Y immobilized {[VO(sal2bz)]2-Y; [Fe(sal2bz)(H2O)2]2-Y} binuclear complexes have been prepared and characterized by spectroscopic techniques (IR, UV–vis), elemental analyses (CHN, ICP-OES), thermal study (TGA), scanning electron micrograph (SEM), adsorption study (BET) and X-ray diffraction (XRD) patterns. Neat (homogeneous) and immobilized (heterogeneous) complexes were employed as catalysts in the oxidation of olefins, namely, cyclohexene, limonene and α-pinene in the presence of 30% hydrogen peroxide. 100% conversion of cyclohexene and α-pinene was obtained while limonene was oxidized up to 90%. Homogeneous catalysts showed highly selective result as neat [VO(sal2bz)]2 complex has provided 87% cyclohexane-1,2-diol and neat [Fe(sal2bz)(H2O)2]2·2H2O complex has provided 79% verbenone in oxidation of cyclohexene and α-pinene, respectively. We have observed that due to steric hindrance, formation of olefinic oxidation products increases on moving from α-pinene to limonene and limonene to cyclohexene. Additionally. recovered heterogeneous catalysts showed intact results up to two consecutive runs. Probable catalytic mechanism has been proposed for oxidation of cyclohexene
Aptamer-based radiopharmaceuticals for diagnostic imaging and targeted radiotherapy of epithelial tumors
In the continuous search for earlier diagnosis and improved therapeutic modalities against cancer, based on our constantly increasing knowledge of cancer biology, aptamers hold the promise to expand on current antibody success, but overcoming some of the problems faced with antibodies as therapeutic or delivery agents in cancer. However, as the first aptamer reached the market as an inhibitor against angiogenesis for the treatment of macular degeneration, aptamers have found only limited applications or interest in oncology, and even less as radiopharmaceuticals for diagnostic imaging and targeted radiotherapy of tumours. Yet, the chemistry for the labelling of aptamers and the options to alter their pharmacokinetic properties, to make them suitable for use as radiopharmaceuticals is now available and recent advances in their development can demonstrate that these molecules would make them ideal delivery vehicles for the development of targeted radiopharmaceuticals that could deliver their radiation load with accuracy to the tumour site, offering improved therapeutic properties and reduced side effects
Oxidation of benzoin catalyzed by oxovanadium (IV) schiff base complexes
BACKGROUND: The oxidative transformation of benzoin to benzil has been accomplished by the use of a wide
variety of reagents or catalysts and different reaction procedures. The conventional oxidizing agents yielded mainly
benzaldehyde or/and benzoic acid and only a trace amount of benzil. The limits of practical utilization of these
reagents involves the use of stoichiometric amounts of corrosive acids or toxic metallic reagents, which in turn
produce undesirable waste materials and required high reaction temperatures.
In recent years, vanadium complexes have attracted much attention for their potential utility as catalysts for various
types of reactions.
RESULTS: Active and selective catalytic systems of new unsymmetrical oxovanadium(IV) Schiff base complexes for
the oxidation of benzoin is reported. The Schiff base ligands are derived between 2-aminoethanol and 2-hydroxy-1-
naphthaldehyde (H2L1) or 3-ethoxy salicylaldehyde (H2L3); and 2-aminophenol and 3-ethoxysalicylaldehyde (H2L2) or
2-hydroxy-1-naphthaldehyde (H2L4). The unsymmetrical Schiff bases behave as tridentate dibasic ONO donor
ligands. Reaction of these Schiff base ligands with oxovanadyl sulphate afforded the mononuclear oxovanadium(IV)
complexes (VIVOLx.H2O), which are characterized by various physico-chemical techniques.
The catalytic oxidation activities of these complexes for benzoin were evaluated using H2O2 as an oxidant. The best
reaction conditions are obtained by considering the effect of solvent, reaction time and temperature. Under the
optimized reaction conditions, VOL4 catalyst showed high conversion (>99%) with excellent selectivity to benzil
(~100%) in a shorter reaction time compared to the other catalysts considered.
CONCLUSION: Four tridentate ONO type Schiff base ligands were synthesized. Complexation of these ligands with
vanadyl(IV) sulphate leads to the formation of new oxovanadium(IV) complexes of type VIVOL.H2O.
Elemental analyses and spectral data of the free ligands and their oxovanadium(IV) complexes were found to be in
good agreement with their structures, indicating high purity of all the compounds.
Oxovanadium complexes were screened for the oxidation of benzoin to benzil using H2O2 as oxidant. The effect of
time, solvent and temperature were optimized to obtain maximum yield. The catalytic activity results demonstrate
that these catalytic systems are both highly active and selective for the oxidation of benzoin under mild reaction
conditions.Web of Scienc
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