Rh(III)-Catalyzed Multi-site-selectivity C-H Bond Functionalization: Condition-Controlled Synthesis of Diversified Fused Polycyclic Benzimidazole Derivatives

High selective activation of multiple sites C-H bonds in a complex organic compound is a huge challenge. Herein, diversified novel fused polycyclic- and multi-substituted 2-oxyl naphthalene benzimidazole derivatives were selectively...

Structural Characterization and Adsorption Capability of Carbonaceous Matters Extracted from Carbonaceous Gold Concentrate

In this paper, the structures of element carbon and humic acid extracted from carbonaceous gold concentrate were characterized employing a variety of analytical methods. The extracted amounts of ECE (elemental carbon extract) and HAE (humic acid extract) were 14.84–38.50 and 11.55–28.05 mg g−1, respectively. SEM and porosity analysis indicated that ECE occurred mostly as irregular blocky particles with a mesoporous surface with the average pore diameter being 31.42 nm. The particle size of ECE was mainly ranged from 5.5 to 42 μm and the specific surface area was 20.35 m2 g−1. The physicochemical features and structure of ECE were close to activated carbon, and the crystallinity was slightly lower than graphite. The particle size distribution of HAE varied from 40 to 400 nm with the specific surface area of 42.84 m2 g−1, whereas the average pore diameter of HAE was 2.97 nm. FTIR and UV–VIS analyses indicated that HAE was a complex organic compound containing the enrichment of oxygen-containing structure. The results showed that the adsorption amounts of ECE and HAE under the acidic conditions were 470.46 and 357.60 mg g−1, respectively. In an alkaline environment, the amount of ECE was 449.02 mg g−1 and the value of HAE was 294.72 mg g−1. ECE mainly utilized the outer surface and mesoporous structure to adsorb gold, while the functional groups’ complexation or surface site adsorption was the leading approach for HAE to adsorb gold.

Characterization of Lignin

Lignin is a complex organic compound crucial to the structural tissues of vascular plants, such as trees. The cyclic structure and aromaticity of lignin give it significant potential to be used as a renewable and safe replacement for toxic aromatic compounds in chemical and industrial processes. The purpose of this experiment was to characterize lignin, specifically the particle diameter and zeta potential, using both the Zetasizer Nano ZSP and the ImageJ image processing software, and to compare the accuracy of both measurement methods. Due to the natural fluorescence of lignin, a fluorescence microscope is used to capture images of lignin particles. By having a known distance and the scale of measurement, with ImageJ it is possible to calculate distances, such as the diameters of particles in images. The Zetasizer Nano ZSP is a device capable of measuring both particle diameter and zeta potential, which is the electrical charge existing on particles suspended in a medium. Small amounts of lignin, in powder form, are placed into scintillation vials with different amounts of distilled water to create 3 different concentrations of sample to measure using the Zetasizer. Between 10-15mL of sample are placed into specialized measurement cells and put into the Zetasizer. Multiple measurements are conducted and averaged to achieve accurate results. The measured zeta potential value is indicative of the stability of the lignin. If the value of zeta potential is higher than 30mV, negative or positive, it has a high stability and low reactivity. The average values of zeta potential measured by the Zetasizer ranged from -27mV to -21mV. The particle diameter is important in characterization, as the smaller and more distributed the particles are, there is a larger surface area for reactions to occur. Average particle diameter measured by the Zetasizer ranged from 926-976µm. The results from the Zetasizer Nano ZSP are more accurate than those from the ImageJ software, as ImageJ allows for a substantial amount of human error to impact the results. The outcomes help direct future experiments using lignin and beneficial to future research concerning lignin and its potential.

Crystal structure of 5′-phenyl-1,1′:3′,1″-terphenyl-4-carboxylic acid, a 27 atoms organic compound by powder method

The crystal structure of a complex organic compound containing 27 independent non-hydrogen atoms in asymmetric unit has been solved from powder diffraction data collected at ESRF Grenoble. Structure model was found using PATSEE program. By Rietveld method the structure was completed and refined to final values of discrepancy factors