The use of NARX neural network for modeling of adsorption of zinc ions using activated almond shell as a potential biosorbent.

In this study, nonlinear autoregressive model processes with exogenous input (NARX) are applied for the prediction of percentage adsorption efficiency for the removal of zinc ions from wastewater by activated almond shell. The effect of operational parameters such as pH, dosage, particle size and initial metal ions concentration are studied to optimize the conditions for maximum removal of zinc ions. The model is first developed using a two layer NARX network. A comparison between the model results and experimental data showed that the NARX model is able to predict the removal of zinc ions from wastewater. The outcomes of suggested NARX modeling were then compared to batch experimental studies. The results show that activated almond shell is an efficient sorbent and NARX network, which is easy to implement and is able to model the batch experimental system.

3,3'-Dimethyl-4,4'-(hexane-1,6-di-yl)bis-[1H-1,2,4-triazol-5(4H)-one].

The title compound, C(12)H(20)N(6)O(2), has a centre of symmetry. The mol-ecule consists of two triazole rings joined by an aliphatic -(CH(2))(6)- chain. The crystal structure is stabilized by inter-molecular N-H⋯O hydrogen bonds and by π-π stacking inter-actions between the triazole rings of inversion-related mol-ecules [centroid-centroid distance = 3.277 (8) Å].

2-Benzoylmethyl-4-[(2-benzylidene-ethylidene)amino]-5-(2-thienylmethyl)-2H-1,2,4-triazol-3(4H)-one.

In the mol-ecule of the title compound, C(24)H(20)N(4)O(2)S, the dihedral angle between the triazole and thio-phene rings is 66.80 (4)° and the dihedral angle between the two benzene rings is 63.37 (4)°. An intra-molecular C-H⋯O inter-action results in the formation of a six-membered ring. A π⋯π contact between the benzene rings, [centroid-centroid distance = 3.918 (2) Å] may stabilize the structure. Weak C-H⋯π inter-actions are also present. The S, C and H atoms of the thiophene ring are disordered over two positions and were refined with occupancies of 0.654 (3) and 0.346 (3).

Synthesis and characterization of some new tetraaldehyde and tetraketone derivatives and X-ray structure of 1,1'-(4,4'-(2-(1,3-bis(4-acetylphenoxy)propan-2-ylidene)propane-1,3-di-yl)bis(oxy)bis(4,1-phenylene))diethanone.

Tetraketone and tetraaldehyde derivatives 2a-d were synthesized via the reaction of ethene-1,1,2,2,-tetra-yl-tetramethylene tetrabromide (1) with hydroxyketone and aldehyde derivatives. The molecular structures were identified by IR, (1)H-NMR, (13)C-NMR and MS analysis. The crystal structure of the title compound 2a, C(38)H(36)O(8), is reported. Its crystal data are: monoclinic, space group P 2(1)/n with cell dimensions of a=9.0395(12) A, b=12.6114(17) A, c=13.8166(18) A, beta=95.875(3), V=1566.8(4) A(3), F.W.=620.67, rho(calc)=1.316 gcm(3) for Z=2, mu=0.092 mm(-1).

C-H...O and C-H...pi interactions in 1-acetyl-4-(p-chlorobenzylideneamino)-3-ethyl-4,5-dihydro-1H-1,2,4-triazol-5-one.

The title compound, C(13)H(13)ClN(4)O(2), contains both a phenyl and a triazole ring, both of which are approximately coplanar with the entire molecule. The triazole ring has substituents at the 1-, 2- and 4-positions. Intramolecular C-H.O and C-H.N interactions, together with intermolecular C-H.O and C-H.pi interactions, help to stabilize the structure.