The leaf chlorophyll content is one of the most important factors for the growth of winter wheat. Visual and near-infrared sensors are a quick and non-destructive testing technology for the estimation of crop leaf chlorophyll content. In this paper, a new approach is developed for leaf chlorophyll content estimation of winter wheat based on visible and near-infrared sensors. First, the sliding ...

How plants interact with sunlight is central to the existence of life and provides a window to the functioning of ecosystems. Although the basic properties of leaf spectra have been known for decades, interpreting canopy-level spectra is more challenging because leaf-level effects are complicated by a host of stem- and canopy-level traits. Progress has been made through empirical analyses and m...

Five new homoleptic [NiX(4)](2-) compounds have been prepared with the fluorinated ligands OC(6)F(5) (OAr(F)), OC(6)H(3)(CF(3))(2) (OAr'), and OC(4)F(9) (OR(F)) and characterized with X-ray crystallography, magnetic susceptibility, and elemental analysis. Electronic spectral studies show that these ligands engender a ligand-field environment similar to that of fluoride and thus act electronical...

Leaf scattering spectrum is the key optical variable that conveys information about leaf absorbing constituents from remote sensing. It cannot be directly measured from space because the radiation scattered from leaves is affected by the 3D canopy structure. In addition, some radiation is specularly reflected at the surface of leaves. This portion of reflected radiation is partly polarized, doe...

High-throughput, noninvasive field phenotyping has revealed genetic variation in crop morphological, developmental, and agronomic traits, but rapid measurements of the underlying physiological and biochemical traits are needed to fully understand genetic variation in plant-environment interactions. This study tested the application of leaf hyperspectral reflectance (λ = 500-2,400 nm) as a high-...

In this paper we explore the use of the novel relativistic intermediate Hamiltonian Fock-space coupled-cluster method in the calculation of the electronic spectrum for small actinyl ions (NpO2+, NpO2(2+), and PuO2(2+)). It is established that the method, in combination with uncontracted double-zeta quality basis sets, yields excitation energies in good agreement with experimental values, and be...

Plant responses to the light spectrum under which plants are grown affect their developmental characteristics in a complicated manner. Lamps widely used to provide growth irradiance emit spectra which are very different from natural daylight spectra. Whereas specific responses of plants to a spectrum differing from natural daylight may sometimes be predictable, the overall plant response is gen...

A microscope device to measure the circular dichroism (CD) spectra of a specified microscopic region of chiral samples was constructed by combining of a couple of objective lenses and a CCD camera, which was installed in a sample chamber of a commercially available CD spectropolarimeter. By using this apparatus, high quality micro-CD spectra in the 60 x 60 microm region of samples could be meas...

We agree with Knyazikhin et al. (1), who reported in a recent issue of PNAS that relationships between foliar nitrogen (%N) and near-infrared (NIR) canopy albedo appeared to be indirect and explained largely by differences in leaf and canopy structure, primarily between conifer and broadleaf species. We disagree, however, with the conclusion that %N–NIR correlations are necessarily spurious. On...