N-(2-Chloro­pyrimidin-4-yl)-N,2-di­methyl-2H-indazol-6-amine

In the title compound, C13H12ClN5, which is a derivative of the anti­tumor agent pazopanib {systematic name: 5-[[4-[(2,3-di­methyl-2H-indazol-6-yl)methylamino]-2-pyrimidinyl]amino]-2-methylbenzolsulfonamide}, the indazole and pyrim­idine fragments form a dihedral angle of 62.63 (5)°. In the crystal, pairs of mol­ecules related by twofold rotational symmetry are linked into dimers through π–π inter­actions between the indazole ring systems [centroid–centroid distance = 3.720 (2) Å]. Weak inter­molecular C—H⋯N hydrogen bonds further assemble these dimers into columns propagated in [001]

Perchlorate, nitrate, and sulfate reduction in hydrogen-based membrane biofilm reactor : model-based evaluation

© 2017 Elsevier B.V. A biofilm model was developed to evaluate the key mechanisms including microbially-mediated ClO4−, NO3−, and SO42−reduction in the H2-based membrane biofilm reactor (MBfR). Sensitivity analysis indicated that the maximum growth rate of H2-based denitrification (μ1) and maximum growth rate of H2-based SO42−reduction (μ3) could be reliably estimated by fitting the model predictions to the experimental measurements. The model was first calibrated using the experimental data of a single-stage H2-based MBfR fed with different combinations of ClO4−, NO3−, and/or SO42−together with a constant dissolved oxygen (DO) concentration at three operating stages. μ1and μ3were determined at 0.133 h−1and 0.0062 h−1, respectively, with a good level of identifiability. The model and the parameter values were further validated based on the experimental data of a two-stage H2-based MBfR system fed with ClO4−, NO3−, SO42−, and DO simultaneously but at different feeding rates during two running phases. The validated model was then applied to evaluate the quantitative and systematic effects of key operating conditions on the reduction of ClO4−, NO3−, and SO42−as well as the steady-state microbial structure in the biofilm of a single-stage H2-based MBfR. The results showed that i) a higher influent ClO4−concentration led to a higher ClO4−removal efficiency, compensated by a slightly decreasing SO42−removal; ii) the H2loading should be properly managed at certain critical level to maximize the ClO4−and NO3−removal while limiting the growth of sulfate reducing bacteria which would occur in the case of excessive H2supply; and iii) a moderate hydraulic retention time and a relatively thin biofilm were required to maintain high-level removal of ClO4−and NO3−but restrict the SO42−reduction

Methyl 5-chloro-2-nitro­benzoate

In the title compound, C8H6ClNO4, the nitro and acet­oxy groups attached to the benzene ring at neighbouring positions are twisted from its plane by 29.4 (1) and 49.7 (1)°, respectively. In the crystal, weak C—H⋯O hydrogen bonds link mol­ecules into layers parallel to (101). The crystal packing exhibits short inter­molecular C⋯O distances of 2.925 (3) Å

2-(Thio­phen-2-yl)ethyl 4-methyl­benzene­sulfonate

In the title mol­ecule, C13H14O3S2, the thio­phene and benzene rings form a dihedral angle of 13.86 (13)°. In the crystal, weak inter­molecular C—H⋯O hydrogen bonds link the mol­ecules into layers parallel to the ab plane

2-Methyl-6-nitro-2H-indazole

In the title compound, C8H7N3O2, the mol­ecular skeleton is almost planar with a maximum deviation of 0.0484 (9) Å for the methyl C atom. In the crystal, weak inter­molecular C—H⋯N and C—H⋯O hydrogen bonds help to establish the packing