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Nitrogen (N) is crucial for plant growth and yield, however excessive N in cotton hampers productivity by excessive vegetative growth, delaying phenological activity, decreasing yield and increase in cost of production. Therefore, it's necessary to find real values of input like N in current fertilizer availability crises. Hence, this experiment was designed to determine the economical optimum dose of N in cotton through empirical modeling during summer season of 2019 and 2020. Experimental treatments were comprised of; 0, 75, 100, 125, 150, 175 and 200 kg N ha−1. Results revealed that higher seed cotton yield (1222 and 1454 kg ha−1) was recorded when 200 Kg N ha−1 was applied that was statistically at par with 150 kg N ha−1 (1041 and 1272 in 2019 and 2020 respectively) and 175 kg N ha−1 (1222 and 1386 kg ha−1 in 2019 and 2020 respectively) was applied. A quadratic relationship was also developed by generating a model to regress the value of ratio of cotton yield and benefit cost ratio (BCR) per unit increase of N even beyond 200 kg N ha−1. Increasing the level from 0 to 200 N kg ha−1 resulted in higher seed cotton yield and BCR (1.54:1 (2019) and 1.35:1 (2020), the curve showed that further increased in N resulted in decrease seed cotton yield and contributed to loss in N. In conclusion, the optimal N level for cotton was found 150 kg N ha−1, however, the economic optimum return could be achieved at 200 kg N ha−1. [ABSTRACT FROM AUTHOR]

Carbon sequestration potential (CSP) and sustainability of gardenpea-french bean cropping system was assessed with farmyard manure (FYM) application vis-à-vis mineral fertilization as recommended NPK (NPK) and integrated nutrient management practices (INM) after six years’ cropping in Indian Himalayas. Application of 20 tons FYM ha−1provided highest CSP (0.527 Mg C ha−1year−1) in soil and sustainability index. With the help of quadratic equations, it was estimated that maximum profit (optimum yield) and turn over of invested money could be achieved with application of 20.0 and 15.6 t FYM ha−1, respectively. Application of 5.9 and 8.9 tons FYM ha−1would substitute NPK and INM, respectively. Pod number plant−1was the most important yield-contributing attribute as found from principal component analysis. Pod yield could be modelled through multiple linear equation with help of yield attributes. [ABSTRACT FROM AUTHOR]

Abstract: The adiabatic approximation in time-dependent density functional theory (TDDFT) yields reliable excitation spectra with great efficiency in many cases, but fundamentally fails for states of double-excitation character. We discuss how double-excitations are at the root of some of the most challenging problems for TDDFT today. We then present new results for (i) the calculation of autoionizing resonances in the helium atom, (ii) understanding the nature of the double excitations appearing in the quadratic response function, and (iii) retrieving double-excitations through a real-time semiclassical approach to correlation in a model quantum dot. [Copyright &y& Elsevier]

Overseeded perennial ryegrass (Lolium perenne L.) aggressively competes with bermudagrass [Cynodon dactylon (L.) Pers.] for resources and may adversely affect spring transition by releasing allelochemicals into the environment. Growth chamber studies examined germination and growth of 'Arizona Common' bermudagrass in soil amended with 0%, 2%, 12%, or 23% perennial ryegrass root or shoot debris or in soil treated with irrigation water in which perennial ryegrass roots at 0, 5, 10, or 20 g⋅L-1 or shoots at 0, 10, or 20 g⋅L-1 had been soaked. Inhibitory effects on bermudagrass germination and growth were most extensive when soil was amended with ryegrass shoot debris, because germination, root ash weight, root length density, and root mass density were reduced 33%, 55%, 30%, and 52%, respectively. Soil amended with ryegrass root debris only inhibited bermudagrass-specific root length. Application of irrigation water containing either ryegrass root or shoot extracts only inhibited bermudagrass-specific root length. In conclusion, results obtained when soil was amended with shoot debris demonstrated perennial ryegrass can inhibit bermudagrass germination and growth in controlled environments. [ABSTRACT FROM AUTHOR]

We present an implementation and validation of the analytical energy gradient of time-dependent density functional theory (TDDFT) using Coulomb-attenuated (CA) functionals for excited state energies, dipole moments, geometries, and vibrational frequencies. The CA-TDDFT gradient is based on the previous long-range corrected TDDFT of (Chiba et al. J Chem Phys 2006, 124, 144106) and the Z-vector formalism of (Furche and Ahlrichs J Chem Phys 2002, 117, 7433). Geometry optimization using CA-TDDFT was carried out for molecules (substituted stilbenes and coumarins) having intramolecular charge-transfer excited states and for a series of small molecules (CO, HCN, CH2O, CH2S, CCl2, C2H2, trans-(CHO)2). We assess the results of the CA functionals, the long-range corrected LC-BLYP functional, and the B3LYP hybrid functional, by comparing to accurate experimental data. The results highlight the applicabilty of different functionals for excited state properties. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [ABSTRACT FROM AUTHOR]

Abstract: Time-dependent density functional theory with quadratic response methodology is used in order to calculate and compare spin–orbit coupling effects and the main mechanism of phosphorescence of the neutral Ir(ppy)3 and cationic [Ir(bpy)3]3+ tris-iridium compounds, [Ir(ppy)2(bpy)]+ and [Ir(2-phenylpyridine)2(4,4′-tert-butyl-2,2′-bipyridine]+ complexes, including also the recently synthesised [Ir(2-phenylpyridine)2(4,4′-dimethylamino-2,2′-bipyridine]+ and [Ir(2,4-difluorophenylpyridine)2(4,4′-dimethylamino-2,2′-bipyridine]+ dyes, where ppy=2-phenylpyridine and bpy=2,2′-bipyridine ligands. Comparison with the symmetric, lighter and more studied [Ru(bpy)3]2+ and [Rh(bpy)3]3+ complexes is also presented. Variations in phosphorescence lifetimes for Ir(ppy)3 and [Ir(bpy)3]3+ dyes as well as for the mixed cationic complexes are well reproduced by the quadratic response method. All the ortho-metalated iridium compounds exhibit strong phosphorescence, which is used in organic light-emitting diodes (OLEDs) to overcome the efficiency limit imposed by the formation of triplet excitons. The results from the first principle theoretical analysis of phosphorescence have helped to clarify the connections between the main features of electronic structure and the photo-physical properties of the studied heavy organometallic OLED materials. [Copyright &y& Elsevier]

Intensity distribution in rotational lines of the 0–0 band of the a1Δg → X3Σg- transition in the oxygen molecule at λ = 1270 nm is studied by quadratic response (QR) method in a framework of multiconfiguration self-consisted field (MCSCF) theory. The distance dependence of the transition magnetic moment and the (0–0)/(0–1) bands intensity ratio are calculated. A short review of previous theory of the red and infrared atmospheric oxygen bands and of their enhancement by collisions is presented to analyze and compare the new results. Enhancement of these bands in O2 collisions with Li2 and N2 molecules is calculated by QR method. Diamagnetic species simulate solvent molecules of different optical polarizability. Specific influence of collisions on vibronic bands is stressed. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 [ABSTRACT FROM AUTHOR]