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Under the hydrothermal method, a Pb(II) coordination polymer [Pb(ox)(phen)2]·5H2O 1 (ox = oxa-late, phen = 1,10-phenanthroline) was obtained. Ox ligands exhibit a m2-coordination mode, which connect Pb2+centers into a 1-D single-chain with ancillary phen molecules. Interestingly, adjacent phen molecules between the chains exist π…π stacking interaction, which extend the 1-D chain into a 2-D supramolecular layer. Compound 1 showed outstanding photocatalytic performance and the degradation efficiency of methylene blue with H2O2could reach 95.69% under the irradiation of visible light at pH = 10. In addition, 5 cycles of degradation experiments were also carried out, and it was found that the degradation efficiency values with and without H2O2were reduced by 1.46% and 1.08%, respectively. It was also discussed that which free radical played the dominant role in the photocatalytic process. What’s more, we speculated the possible reaction mechanism based on the Mott–Schottky curve. Meanwhile, the UV visible diffuse reflection of compound 1 was also investigated.

Three isostructural transition M2+compounds containing SCN-and 1,10-phenantroline (phen), [M(SCN)2(phen)2] (M2+= Cd2+1, Mn2+2, Zn2+3), were synthesized under hydrothermal conditions. Noteworthily, the SCN-in the compounds were all originated from the in situreaction of ligand. Although they were only mononuclear structure, they all further self-assemble into interesting supramolecular networks via π···πstacking of aromatic rings. The different interaction contacts of the molecule and the molecular packing strength in the compounds were investigated using Hirshfeld surface. The energy composition of these compounds was studied by energy framework. Meanwhile, the UV visible diffuse reflection of compounds 1–3was also investigated. The photocatalytic activity toward methylene blue (MB) showed that the highest degradation efficiency reached 92.2 % for 1, 86.3 % for 2and 93.7 % for 3at pH = 10, respectively. The photocatalytic stability of compound 1–3was confirmed by cyclic experiments and PXRD analysis. The possible reaction mechanism was inferred based on the Radical trapping experiments and Mott–Schottky curve. Radical trapping experiments was conducted to determine the active species involved in the catalytic reaction.

A novel supra-molecular compound [Mn(SCN)2(byp)2] 1(byp = 2,2'-bipyridine) was synthesized under hydrothermal conditions. Noteworthily, the SCN-in the title compound is derived from the in situreaction of salicylaldehyde thiosemicarbazone. X-ray single-crystal diffraction analysis shows compound 1is only a mononuclear structure, but it is expanded into a 3D supramolecular structure viaH-bonds and π···πstacking. Hirshfeld Surface analysis shows C⋯H, H⋯H and S⋯H interaction are the main contribution of intermolecular interactions in the formation of compound 1. All of title compounds were characterized by IR spectroscopy, elemental analysis, XRD, XPS and TG analysis. The energy framework of compound 1is dominated by dispersion interaction. The photocatalytic degradation ability of compound 1for methylene blue is verified by photocatalytic degradation experiments (pH = 4: 44.6%; pH = 7: 76.2%; pH = 10: 78.8%). Furthermore, the potential photocatalytic mechanism of compound 1is inferred by UV-vis absorption spectra and Mott–Schottky curve.

Biosparging is one of the effective in situ-technology to removal the organic contaminants. The experiments of removing MTBE by biosparging were carried out in a soil column. the results showed that there were the tailing of contaminants in the column without microorganism according with the microorganism. The removal of organic contaminants by biosparging was simulated by a mathematical model, which considered the advective flux, diffusion, mechanical dispersion, interphase mass transfer and biodegrade. The simulation results agreed with the experimental results well.

ABSTRACTThis paper presents a novice heuristic algorithm, Water Flow-like Algorithm (WFA), for solving discrete optimization problems, particularly the bin packing problems. WFA simulates solution agents as water flows traversing the terrain mapped from the objective function. Governed by the gravitation force, water flows from higher attitudes to lower ones. Driven by the fluid momentum, water flows adjust their compositions and directions against the landforms by splitting into and merging from other flows. Water flows are allowed to move upward to higher attitudes once they possess enough momentum to overcome the potential barrier. Mostly, at least one flow can travel to the lowest region of the terrain under the consideration. In the atmosphere, some water of a flow will evaporate and return to the ground by precipitation. Inspired by the water flowing of the nature, WFA is designed as an optimization algorithm performing the water flow splitting, merging, and dropping (precipitation) operations to traverse the solution space. The number of solution agents deployed is dynamically changing. WFA is an evolutionary algorithm involving four water flow operations: splitting and moving, merging, evaporation, and precipitation. The computational flow and the four operations are extensively discussed. In addition to general operations of WFA, specific operations for bin packing problems are presented. A designed problem and a benchmark problem from OR-Lib are used to test WFA and to compare results with other methods, such as GA, POS, and EM. Numerical results show that WFA outperforms others in solving these BPPs.