A Novel Method for Calibration of Digital Soil Images Captured under Irregular Lighting Conditions.

Soil color is commonly used as an indicator to classify soil and identify its properties. However, color-based soil assessments are susceptible to variations in light conditions and the subjectivity of visual evaluations. This study proposes a novel method of calibrating digital images of soil, regardless of lighting conditions, to ensure accurate identification. Two different color space models, RGB and CIELAB, were assessed in terms of their potential utility in calibrating changes to soil color in digital images. The latter system was determined to be suitable, as a result of its ability to accurately reflect illuminance and color temperature. Linear regression equations relating soil color and light conditions were developed based on digital images of four different types of soil samples, each photographed under 15 different light conditions. The proposed method can be applied to calibrate variations in the soil color obtained by digital images, thus allowing for more standardized, objective, and accurate classification and evaluation of soil based on its color.

Cationic Ti Complexes with Three [N,O]-Type Tetrazolyl Ligands: Ti↔Fe Transmetalation within Fe Metallascorpionate Complexes.

Herein, we report the synthesis of two novel ionic Ti complexes possessing three [N,O]-type bidentate ligands from the reaction of Fe metallascorpionate ligands possessing extended alcohol groups and TiCl4. The reaction of substituted hydroxyphenyl tetrazole and Fe(ClO4)3 in a molar ratio of 3:1 afforded iron scorpionate metalloligands possessing extended arms, which were characterized by IR spectroscopy and ESI-TOF-MS spectrometry. Their molecular structures were also confirmed as neutral Fe-centered scorpionate complexes by X-ray crystallography, in which the extended alcohol groups adopted a tripodal geometry. Moreover, two different crystals of iron scorpionate metalloligand grown from CH2Cl2 and CH3OH were studied, revealing that, in the latter crystal, the tripod arms are folded and aligned toward the C3-rotational axis of the molecule, whereas the tripod arms are unfolded and spread outward from the rotational axis in the former crystal. These metalloligands are solvatochromatic; a bathochromic shift was observed as the solvent polarity increased. From the reaction, the aforesaid Fe complexes were further reacted with TiCl4 in a molar ratio of 1:1 to produce ionic [TiL3]+[FeCl4]- (L = substituted hydroxyphenyl tetrazole) complexes from the transmetalation of Ti and Fe. The complexes were characterized by various analytical methods including UV/vis and IR spectroscopies, electrospray time-of-flight mass spectrometry (ESI-TOF-MS), and X-ray crystallography.

New class of scorpionate: tris(tetrazolyl)-iron complex and its different coordination modes for alkali metal ions.

We report formation of a new metallascorpionate ligand, [FeL3](3-) (IPtz), containing a Fe core and three 5-(2-hydroxyphenyl)-1H-tetrazole (LH2) ligands. It features two different binding sites, oxygen and nitrogen triangles, which consist of three oxygen or nitrogen donors from tetrazole. The binding affinities of the complex for three alkali metal ions were studied using UV spectrophotometry titrations. All three alkali metal ions show high affinities and binding constants (>3 × 10(6) M(-1)), based on the 1:1 binding isotherms to IPtz. The coordination modes of the alkali metals and IPtz in the solid were studied using X-ray crystallography; two different electron-donor sites show different coordination numbers for Li(+), Na(+), and K(+) ions. The oxygen triangles have the κ(2) coordination mode with Li(+) and κ(3) coordination mode with Na(+) and K(+) ions, whereas the nitrogen triangles show κ(3) coordination with K(+) only. The different binding affinities of IPtz in the solid were manipulated using multiple metal precursors. A Fe-K-Zn trimetallic complex was constructed by assembly of an IPtz ligand, K, and Zn precursors and characterized using X-ray crystallography. Oxygen donors are coordinated with the K ion via the κ(3) coordination mode, and nitrogen donors are coordinated with Zn metal by κ(3) coordination. The solid-state structure was confirmed to be a honeycomb coordination polymer with a one-dimensional infinite metallic array, i.e., -(K-K-Fe-Zn-Fe-K)n-.

4-{[(1S,2R)-2-Hy-droxy-indan-1-yl]amino}-pent-3-en-2-one.

In the mol-ecule of the title compound, C(14)H(17)NO(2), the dihedral angle formed by the mean planes through the indan ring system and the amino-pentenone fragment is 83.26 (13)°. An intra-molecular N-H⋯O hydrogen bond is observed. In the crystal, mol-ecules are linked into one-dimensional chains extending along the [010] direction via O-H⋯O and C-H⋯O hydrogen bonds.

(1S,2R)-1-[(E)-(Thio-phen-2-yl-methyl-idene)amino]-indan-2-ol.

In the title compound, C(14)H(13)NOS, the dihedral angle formed by the mean planes through the indane ring system and the thio-phene ring is 85.04 (11)°. The imine bond is located in the thio-phene plane [the S-C-C-N torsion angle is 0.00 (3)°] and an intra-molecular O-H⋯N hydrogen bond is observed.

Bis(µ-trimethyl-silanolato-κO:O)bis-{[2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentyl-phenolato-κN,O]zinc}.

The binuclear title complex, [Zn(2)(C(22)H(28)N(3)O)(2)(C(3)H(9)OSi)(2)], has a crystallographic imposed centre of symmetry. The Zn(II) atom is coordinated by three O and one N atom from one 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentyl-phenolate ligand and two bridging trimethyl-silanolate anions in a distorted tetra-hedral geometry. The dihedral angle between the benzotriazole ring system and the benzene ring is 19.83 (5)°. The tert-pentyl groups are disordered over two orientations with refined site-occupancy ratios of 0.858 (4):0.142 (4) and 0.665 (6):0.335 (6).