2400 chn elemental

The carbon (C) contents in the soil were analyzed using a Perkin-Elmer 2400 CHN elemental analyzer. The filtered (0.45 µm PTFE filter) extract was measured for DOC using a TOC/TN analyzer (multi N/C 3000, Analytik Jena AG, Germany). The pH was determined in 1∶2.5 (w/v) soil:water extracts using a pH electrode. Electrical conductivity (EC) was determined using a conductivity meter (LF91, German). The Al and Si concentrations in the soil FA extracts were measured using ICP-AES (Optima 7000, PerkinElmer, USA). Mineralogical identification was performed using X-ray powder diffraction (Nanjing Normal University). The diffraction patterns were recorded from 3 to 60° 2-theta using Ni-filtered Cu K-alpha radiation at a rate of 300 s per step on a PANalytical X-pert Pro diffractometer using an X-celerator position-sensitive detector.

The FT-IR 460 PLUS Spectrophotometer was used to capture IR spectra in Potassium bromide plates in the 4000–400 cm⁻¹ range. DMSO-d6 was used as a solvent to acquire the proton nuclear magnetic resonance spectra using a Varian Mercury VX-300 NMR Spectrometer. Shimadzu UV-3101PC was used for measuring the electronic absorption spectra where ethanol was used as solvent. Shimadzu TGA-50H was used for carrying out the thermal analysis. TG-DTG measurements were performed in an environment of N₂ at temperatures ranging from 0 °C to 1000 °C where the sample mass was precisely measured out in an aluminum crucible. Elemental analysis was carried out using a PerkinElmer 2400 CHN elemental analyzer. With a Gouy balance, a Sherwood scientific magnetic scale, and H_g[Co(CSN)⁴] as the signing, the magnetic susceptibilities of the powdered materials were tested at ambient temperature. CONSORT K410 was used to analyze the molar conductance of 1 × 10⁻³ M solutions of the ligands and their complexes in ethanol. Each experiment was run at room temperature with freshly made solutions. The progress of the reaction was monitored by thin-layer chromatography (TLC).

All the materials and reagents were obtained commercially without further purification. The FT-IR spectra were recorded in the range of 400–4000 cm⁻¹ using KBr pellets on an EQUINOX55 FT/IR spectrophotometer. Elemental analysis (C, H, N) was implemented on a Perkin-Elmer 2400 CHN elemental analyzer. The phase purity of the bulk or polycrystalline samples were confirmed by powder X-ray diffraction (PXRD) measurements executed on a Rigaku RU200 diffractometer at 60 kV, 300 mA, and Cu Kα radiation (λ = 1.5406 Å), with a scan speed of 5° min⁻¹ and a step size of 0.02° in 2θ. Diffuse reflectance spectra were obtained by a U-41000 spectrophotometer applying BaSO₄ powder as a 100% reflectance reference. Magnetic measurements were performed in the temperature range of 1.8–300 K with an applied field of 1000 Oe, using a Quantum Design MPMS-XL-7 SQUID magnetometer on polycrystalline samples. The diamagnetic corrections for the compounds were estimated using Pascal's constants. Alternating current (ac) susceptibility experiments were performed using an oscillating ac field of 2.0 Oe at ac frequencies ranging from 1 to 1000 Hz. The magnetization was measured in the field range 0–7 T.