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141.
Soudamini Mohapatra Rekha Ajithakumar 《International journal of environmental analytical chemistry》2013,93(5):506-518
Trifloxystrobin and tebuconazole are used for control of Sigatoka leaf spot disease of banana. This study was conducted to evaluate residue persistence of the fungicides in/on banana fruit, other edible parts and soil after spray application of the combination formulation, Nativo 75 WG, at the standard dose, 87.5 + 175 and double dose, 175 + 350 g a.i. ha?1. The fungicides were extracted from banana and soil with acetone, partitioned into dichloromethane and cleaned-up using activated charcoal for trifloxystrobin and primary/secondary amine (PSA) for tebuconazole samples. The limit of quantification of the method was 0.05 mg kg?1 for both fungicides. Initial residues of trifloxystrobin were 0.444 and 0.552 mg kg?1 in/on banana with peel (whole fruit), which reached <0.05 and 0.065 mg kg?1 after 30 days from treatment at the standard and double doses, respectively. Tebuconazole residues were 0.636 and 960 mg kg?1 initially and reduced to 0.066 and 0.101 mg kg?1 after 30 days. Trifloxystrobin and tebuconazole degraded with the half-life of about 11 days. Trifloxystrobin or its metabolite was not detected in the fruit pulp. Tebuconazole being systemic in nature moved to the fruit pulp which was highest on the 3rd day (0.103 and 0.147 mg kg?1) and remained for 15 days. Matured banana fruit, flower, pseudostem and field soil were free from fungicide residues. For consumption of raw banana 43 days pre-harvest interval (PHI) is required after treatment of the combination formulation. Therefore application of the fungicides towards maturity stage of the fruits may be avoided. 相似文献
142.
A comprehensive study regarding the speciation of uranium in five different solids, namely, YBO3, Sr2P2O7, SrB4O7, SrBPO5 and SrZrO3 is presented using time resolved photoluminescence spectroscopy. The ‘Sr’ based hosts are considered as potential phosphor materials where as the borate based matrices are known to have near tissue equivalent absorption coefficients making them potential candidates for dosimetric applications. It was observed that, in case of the pyrophosphate, borophosphate and yttrium borate matrices, uranium gets stabilized as uranyl ( \( {\text{UO}}_{2}^{2 + } \) ), whereas, in case of the tetraborate and zirconate matrices, it was the uranate species, \( {\text{UO}}_{6}^{6 - } \) that gets stabilized preferentially. 相似文献
143.
Degradation of bisphenol A (BPA), an endocrine disruptor, from wastewater sludge (WWS) has attracted great interest recently. In the present study, the effects of different pre-treatment methods, including ultrasonication (US), Fenton's oxidation (FO) and ferro-sonication (FS) was assessed in terms of increase in solubilization of WWS and simultaneous degradation of BPA. Among US, FO and FS pre-treatment, higher suspended solids (SS), volatile suspended solids (VSS), chemical oxygen demand (COD) and soluble organic carbon (SOC) solubilization (39.7%, 51.2%, 64.5% and 17.6%, respectively) was observed during a ferro-sonication pre-treatment process carried out for 180 min, resulting in higher degradation of BPA (82.7%). In addition, the effect of rheological parameters (viscosity and particle size) and zeta potential on the degradation of BPA in raw and different pre-treated sludges were also investigated. The results showed that a decrease in viscosity and particle size and an increase in zeta potential resulted in higher degradation of BPA. BPA degradation by laccases produced by Sinorhizobium meliloti in raw and pre-treated sludge was also determined. Higher activity of laccases (207.9 U L(-1)) was observed in ferro-sonicated pre-treated sludge (180 min ultrasonic time), resulting in higher removal of BPA (0.083 μg g(-1)), suggesting concomitant biological degradation of BPA. 相似文献
144.
Jugal Mohapatra Srinivasan Natesan 《Journal of Applied Mathematics and Computing》2011,37(1-2):247-265
In this paper, we present the analysis of an upwind scheme for obtaining the solution of a convection-diffusion two-point boundary value problem with Robin boundary conditions. The solution is obtained on a suitable nonuniform mesh which is formed by equidistributing the arc-length monitor function. It is shown that the discrete solution obtained by the upwind scheme converges uniformly with respect to the perturbation parameter. Numerical results are presented that demonstrate the sharpness of the theoretical estimates. 相似文献
145.
The forces of interaction as reflected in the cosθ plane analytic structures of the helicity amplitudes of Σ−-p and Λ-p scattering are optimally exploited using the conformal mapping technique of Cutkosky and coworkers. A suitable parametrization
of these amplitudes in the mapped variable is then chosen so that it can see the zeros better. These zeros are then located
by making a good fit to the differential scattering cross-section curves. The effect of these zeros upon the cross-sections
is discussed. Values for the phase shifts and coupling parameters between channels of fixedJ values are also computed. 相似文献
146.
147.
We analyze proton decays and neutron oscillations in the rishon model. Proton decay is forbidden in lowest order of the compositeness scale ΛH. In a one-generation rishon model, the leading proton decays violate B?L (e.g., p→νπ+). The lifetime is given by τp~ΛH8/(UR2mp7), where UR~M(WR) is the mass scale of the right-handed W boson and mp is the proton mass. For UR~500 GeV, the obtained limit for the compositeness scale is ΛH?108 GeV. Neutron oscillations are also proportional to ΛH8 and cannot be detected in the foreseeable future. All of these predictions may depend strongly on the understanding of higher generations of quarks and leptons within the model. 相似文献
148.
We seek an interpretation of the U(1) part of the electroweak symmetry group in terms of the quantum number B ? L. We show that the electroweak symmetry group, for which U(1) can be interpreted as a local B ? L symmetry, is the left-right symmetry group SU(2)L × SU(2)R × U(1)L+R. The equating of UL+R(1) to UB?L(1) should lead to physical consequences which are not shared by standard gauge theory. B ? L may also help to explain the inversion of quark and lepton mass spectra. 相似文献
149.
Mohapatra Rabindra N. Senjanović Goran 《Zeitschrift fur Physik C Particles and Fields》1983,18(1):53-56
Zeitschrift für Physik C Particles and Fields - It is argued that the Peccei—QuinnU(1) PQ symmetry, needed to solve the strong CP-problem, and the localB−L symmetry of weak... 相似文献
150.
Subhashree Mohapatra Sashikumaar Ganesan 《Numerical Functional Analysis & Optimization》2016,37(10):1295-1311
In this article, we propose a non-conforming exponentially accurate least-squares spectral element method for Oseen equations in primitive variable formulation that is applicable to both two- and three-dimensional domains. First-order reformulation is avoided, and the condition number is controlled by a suitable preconditioner for velocity components and pressure variable. A preconditioned conjugate gradient method is used to obtain the solution. Navier-Stokes equations in primitive variable formulation have been solved by solving a sequence of Oseen type iterations. For numerical test cases, similar order convergence has been achieved for all Reynolds number cases at the cost of higher iteration number for higher Reynolds number. 相似文献