The title compound, C14H11BrN4O4, comprises two crystallographically independent mol­ecules (A and B) in the asymmetric unit. In mol­ecule B, intra­molecular bifurcated N—H⋯O and N—H⋯Br hydrogen bonds and in mol­ecule A, an intra­molecular N—H⋯O hydrogen bond generate S(6) ring motifs. The dihedral angle between the phenyl and benzene rings is 5.44 (6) in mol­ecule A and 7.63 (6)° in mol­ecule B. The ortho- and meta-nitro substituents make dihedral angles of 6.67 (15) and 2.26 (15)° to the attached benzene ring in mol­ecule A and 6.37 (17) and 5.81 (16)° in mol­ecule B. The Br atom in mol­ecule B is disordered over two positions with a refined site-occupancy ratio of 0.61 (3):0.39 (3). Inter­esting features of the crystal structure are the short Br⋯N [3.257 (3)–3.294 (4) Å], Br⋯O [3.279 (3)–3.307 (4) Å] and O⋯O [2.9319 (16)–2.9995 (16) Å] contacts, which are shorter than the sum of the van der Waals radii of these atoms. The crystal structure is further stabilized by inter­molecular C—H⋯O and π–π inter­actions [centroid–centroid distances = 3.6643 (8)–3.8514 (8) Å].

Pineapple cultivation in nitrogen deficient and acidic peat soils leads to poor growth, yield, and fruit quality of pineapples. A study was conducted to determine whether clinoptilolite zeolite (CZ) could improve soil nitrogen availability, growth, yield, and fruit quality of pineapples grown in drained peat soils. Laboratory leaching experiments were conducted to determine the effectiveness of CZ in controlling nitrogen loss from peat soils, whereas an ion-exchange resin method was used to determine nitrogen availability in pineapple cultivation. Treatments evaluated were: (i) different amounts of CZ (25, 50, 70, and 100%) + NPK fertilizer, (ii) NPK fertilizer, and (iii) peat soil only. The peat soils with CZ reduced ammonium and nitrate losses because of the sorption of ammonium within the lattices of the CZ via ion exchange. Co-application of CZ (25%) and NPK fertilizers was more effective in increasing soil ammonium availability, whereas the use of CZ (25% to 100%) improved nitrogen uptake and use efficiency, growth, yield, and fruit quality of pineapple because CZ could regulate the availability of nitrogen ions for pineapple uptake. The buffering capacity of CZ increased soil pH and facilitated organic nitrogen mineralization. The co-application of CZ and NPK fertilizers can be used to improve nitrogen availability and pineapple productivity in tropical peat soils.

Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.001 Å; disorder in main residue; R factor = 0.041; wR factor = 0.119; data-to-parameter ratio = 38.8.The title thiosemicarbazone derivative, C 12 H 18 N 4 S, features intramolecular N-HÁ Á ÁN and C-HÁ Á ÁS hydrogen bonds which generate S(5) ring motifs. The dihedral angle between the benzene ring and the thiourea unit is 6.30 (6) indicating planarity in the molecule. Intermolecular N-HÁ Á ÁS hydrogen bonds generate dimers with an R 2 2 (8) ring motif. The methyl group of the N-ethyl residue is disordered and was refined with site occupancies of 0.521 (5) and 0.479 (5). Related literature

Sorbent materials based on a hydrazone Schiff base compound, C14H11BrN4O4, were prepared either by immobilizing the ligand into sol-gel (SG1) or bonding to silica (SG2). The sorbent materials were characterized by FT-IR, EDX, SEM, TEM, and TGA. The sorption characteristics of a matrix of eight transition metal ions (Ag+, Cu2+, Co2+, Ni2+, Fe3+, Pb2+, Zn2+, and Mn2+) using batch method were studied. Several key parameters that affected the extraction efficiency such as pH, contact time, metal ions concentration, and gel size (for SGl) were investigated and optimized. Under the optimized conditions, the physically immobilized hydrazone sorbent (SG1) exhibits highest selectivity towards Ag+ ions, while the chemically bonded hydrazone sorbent (SG2) exhibits high extraction for all metal ions tested. However, for practical applications such as the removal and preconcentration of Ag+, the physically immobilized sorbent (SG1) is preferred.