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Various nanoporous particles, nanofibers have been employed for adsorptive removal of dyes from wastewater. However, these nanomaterials are difficult in separation from solution, generally by centrifugation or filtration. These processes are tedious and will limit the upscale applications. Herein, a hierarchically porous carbon monolith has been fabricated on grounds of ice and metal organic framework (MOF) templating method. The prepared carbonaceous monolith exhibited abundant ice-templated macropores, MOF-templated micropores and mesopores, and a high BET (Brunauer-Emmett-Teller) special surface area (530 m2 g−1). The monolith achieved an MB (methylene blue) adsorption capacity of 95.82 mg g−1 (10 mg adsorbent/5 mL aqueous dye solution) and a theoretic maximum value of 179.86 mg g−1 by the Langmuir model. Compared with MB, the adsorption capacity for MO (methyl orange) was lower. Several adsorption kinetics and isotherms models were used for analysis of adsorptive data, and the results demonstrated the adsorption of MB and MO on the porous carbon monolith is a spontaneous endothermic physisorption process, which was mainly controlled by electrostatic reaction. Importantly, the monolith could be easily picked up using tweezers and used for recycling tests. After four cycles, the 94% of the initial adsorption capacity for MB can be retained.

Porous titanium (PT) is considered as a promising biomaterials for orthopedic implants. Besides biocompatibility and mechanical properties, corrosion resistance in physiological environment is the other important factor affecting the long stability of an implant. In order to investigate the corrosion behavior of porous titanium implants in a dynamic physiological environment, a dynamic circle system was designed in this study. Then a titanium-based implant with PT coating was fabricated by plasma spraying. The corrosion resistance of PT samples in flowing 0.9% NaCl solution was evaluated by electrochemical measurements. Commercial pure solid titanium (ST) disc was used as a control. The studies of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) show that the pores in the PT play a negetive part in corrosion resistance and the flowing electrolyte can increase the corrosive rate of all titanium samples. The results suggest that pore design of titanium implants should pay attention to the effect of dynamic process of a physiological environment on the corrosion behavior of implants.

A duplex coating (called MAOB coating) was fabricated on AZ91D Mg alloy by combining the process of micro-arc oxidation (MAO) with baking coating (B-coating). The structure, composition, corrosion resistance, and tribological behaviour of the coatings were investigated using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), electrochemical and long-term immersion test, and ball-on-disc friction test. The results show that a dense 92 μm thick B-coating was tightly deposited onto the MAO-coated Mg alloy and exhibited a good mechanical interlock along the rough interface. Compared with the MAO-coated sample, the corrosion current density of the MAOB-coated Mg alloy decreased by two or three orders of magnitude and no corrosion phenomenon was observed during a long-term immersion test of about 500 h (severe corrosion pits were found for MAO-treated samples after about 168 h of immersion). The frictional coefficient values of the MAOB coating were similar to those of the MAO coating using dry sliding tests, while the B-coating on the MAO-coated surface significantly improved the wear resistance of the AZ91D Mg alloy. All of these results indicate that a B-coating can be used to further protect Mg alloys from corrosion and wear by providing a thick, dense barrier.

Micro-arc oxidation (MAO) coatings were obtained on AZ91D Mg alloy in an alkaline Na2SiO3-NaF base solution with and without K2ZrF6. Then, the surface and cross-sectional morphologies, elemental compositions and phase structure of the resulting coatings were investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD), respectively. The corrosion behaviour of the coatings was evaluated by potential dynamic polarization (PDP) curves and electrochemical impedance spectroscopy (EIS) in 3.5 wt.% NaCl solution. The results show that the self-sealing MAO coating which consists of MgO, MgF2, t-ZrO2, MgSiO3 and amorphous phosphate related to Mg can be fabricated in a K2ZrF6-containing electrolyte solution. With increasing K2ZrF6 content, the coating exhibits a more dense cross-sectional morphology and less coating defects, along with better anticorrosion properties than the traditional MAO coating. The ZrF62− plays an important role in producing the self-sealing MAO coating, which results in a three-layer structure: MgO-rich inner layer, MgF2-rich sealed pore layer and porous outer layer. The hydrolysed ZrO2 can promote the formation of the seal pores during MAO process due to its high boiling point.

A novel mixed-ligand complex, [Cd(im)6][Cd(im)3(H2O)3]2(ans)6·8H2O (1), was obtained from the reaction ofCd(OAc)2·2H2O, imidazole (im) and sodium 4-aminonaphthalene-1-sulfonate tetrahydrate (Na-ans) in a mixed solvent at 25 °C. The complex was characterized by elemental analysis, IR spectroscopy, and X-ray single crystal diffraction. There are two kinds of cations constructed by CdII atoms with a octahedral coordination arrangement in 1. The CdII atom is bonded by six nitrogen atoms from six im ligands in the first cation, and the second central CdII atom is bonded by three nitrogen atoms of im molecules and three oxygen atoms belonging to water molecules. The ans anion acts as a counterion to balance the charge, and the adjacent anions are reversed but non-parallel interlinked by N–H···O(S) hydrogen bonds into graphite-like 2D sheet viewed from the c axis. The anionic channels along the [110] direction are filled with the cations, and the two kinds of cations are alternatingly arranged in the channels. The hydrogen-bonding interactions together with the ionic bonds stabilize the crystal structure. The thermostability of the complex was investigated by TG and DSC.

Four novel mixed-ligand complexes were obtained from the reaction of maleic acid, diimine chelating ligands and Cd(OH)2 or CdO in a mixed solvent of water and methanol. The complexes were characterized by IR spectroscopy, elemental analysis, and single-crystal X-ray diffraction. The results show that all the four complexes are coordination polymers. [Cd(phen)(H2O)(male)]n·2nH2O (1) and [Cd(bipy)(H2O)(male)]n·2nH2O (2) (male = maleate; phen = 1, 10-phenanthroline, bipy = 2, 2′-bipyridine) are isomorphic, and the asymmetric unit is constructed by one CdII atom, a maleate group, a diimine ligand and two crystal water molecules. Each maleate group links two CdII atoms in a bis(bidentate) chelating mode, resulting in a 1D helical chain. Within [Cd(phen)(H2O)2(male)]n·2nH2O (3), the maleate group bridges two CdII atoms in a bis(monodentate) chelating mode into a 1D helical chain along the [100] direction. The helical chain is decorated by phen groups alternatively at the two sides, and each phen plane of one chain is inserted in the void space between two adjacent phen ligands from an adjacent chain, resulting in a double zipper-like chain. The asymmetric unit of [Cd2(phen)2(male)2]n (4) contains a CdII cation, one phen molecule, and a maleate group, and one bridging maleate group links three CdII atoms resulting in a 2D layer extending in [011] plane. The 2D networks are constructed by four kinds of rings formed by the central metal atom and maleate dianion. The thermostabilities of the four complexes were investigated.

Rock fracture process that shows strong nonlinearity and complexity is simulated by cellular automata method. Cellular automata are considered as an efficient method to simulate complex system and study mechanisms of physical phenomena due to their locality and parallelization. In this paper rock samples can be discretized into cell elements that are connected with beam elements. Force and displacement are taken as the basic state variables. Based on equilibrium equations, constitutive equations and deformation equations local rules are attained, which overcomes the shortcoming of arbitrary decision of local rules. Maximum tensile strain criterion and Mohr-Coulomb criterion are introduced to judge the beginning of tensile failure and shearing failure respectively. And based on damage mechanics deformation and strength properties of damaged cell elements are estimated. This model can simulate heterogeneity of rock and crack propagation and coalescence. Finally based on this model fracture process and crack propagation and coalescence are simulated. The simulated results are in good accordance with typical experimental results and it proved that cellular automata method is a promising method to study rock fracture.