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The growth of CVD diamond film was simulated by using revised KMC method. The simulation was conducted at CH3 radical concentration (0.01%-0.03%) and atomic hydrogen concentration (0.01%-0.5%). The results showed that: The CVD diamond film growth under revised KMC method is superior, which is in good agreement with the experimental results. The concentration of CH3 ([CH3]) and the concentration of atomic H ([H]) can produce important effects on the film deposition rate, surface roughness and the concentration of atom H embedded in the film.

In order to understanding of the fate and transport of TiO2 nanoparticles (NPs) in the water treatment process, this study focused on the particle surface characteristics and hydrodynamic properties at different humic acid (HA) concentration, using aluminum sulfate (AS) as a coagulant. The changes of zeta potential of humic acid capped TiO2 NPs and flocs were measured by Malvern Zetasizer nanoZS. The surface functional group of flocs was investigated using FT-IR spectra. The growth velocity of alum-TiO2 NPs flocs were determined using a small-angle light scattering technique during the coagulation process.Experimental results indicated that the zeta potential of alum-TiO2 NPs flocs surface after adsorption of humic acid was related with humic acid concentration. Adsorption of humic acid resulted in more negative electrophoresis on the surface. Size and growth velocity of alum-TiO2 NPs flocs were estimated at different humic acid concentration. It was found that the flocs growed were faster in the presence of humic acid, while humic acid had adverse influences on the growth of alum-TiO2 NPs flocs.

It is studied that influence of Li vapor transport equilibration (VTE) on surface refractive index of congruent Mg (4.5 mol%):LiNbO3crystal at wavelength of 1536 nm. The results show the ordinary index nodecreases when t < 40 h, then recoveries slightly and tends to a constant when t >100 h. The extraordinary index nehas the VTE effects as similar as no, but the alteration amplitude is smaller than no. The secondary ion mass spectrometry) study shows that the VTE induces Mg diffusion within the crystal in an inhomogeneous Mg depth profile, depending on the VTE duration. The neutron activation analysis shows that the VTE hardly induces Mg evaporation away from the crystal. First, the Mg ions of crystal internal diffused to the surface in the early stage of VTE, and then they diffused slowly back into the bulk of the crystal toward equilibrium when Li concentration tends to equilibrium.

In order to understanding of the fate and transport of TiO2 nanoparticles (Nps) in the water treatment process, this study focused on the impact of humic acid (HA) on the aggregation and charge behavior of TiO2 Nps, and investigated the removability of TiO2 Nps stabilized by HA during the coagulation process. Malvern Zetasizer nanoZS measured the changes of size and zeta potential of HA capped TiO2 Nps (HA-TiO2). Uv-vis spectrometer examined the aggregation behavior of TiO2 and HA-TiO2 NPs at different pH value. Jar tests were conducted to evaluate the removal efficiency of TiO2 NPs. HA adsorbed on the surface of TiO2 Nps could decrease the zeta potential values and enhance the stability of TiO2 Nps. TiO2 Nps could be effectively removed by aluminum sulfate (AS) under favorable condition. HA could influence the removal of TiO2 Nps during the coagulation processes. Low concentration of HA rejected the removal efficiency of TiO2 Nps, however, high concentration of HA promoted removing effectiveness.

Metal–organic frameworks (MOFs) are typically built by assembly of metal centres and organic linkers, and have emerged as promising crystalline materials in a variety of fields. However, the stability of MOFs is a key limitation for their practical applications. Herein, we report a novel Sr 2+ -MOF [Sr 4 (Tdada) 2 (H 2 O) 3 (DMF) 2 ] (denoted as NKU- 105 , NKU = Nankai University; H 4 Tdada = 5,5'-((thiophene-2,5-dicar bonyl)bis(azanediyl))diisophthalic acid; DMF = N,N -dimethylformamide) featuring an open square channel of about 6 Å along the c -axis. Notably, NKU- 105 exhibits much outstanding chemical stability against common organic solvents, boiling water, acids and bases, relative to most MOF materials. Furthermore, NKU- 105 is an environment-friendly luminescent material with a bright cyan emission. This article is part of the themed issue ‘Coordination polymers and metal–organic frameworks: materials by design’.

The growth of {111}-oriented CVD diamond film under a two-step model was simulated at atomic scale by using revised KMC method. The simulation was conducted at various substrate temperature (1100K-1400K), CH3 radical concentration (0.01%-0.03%) and atomic hydrogen concentration (0.005%-0.3%). The results showed that: Substrate temperature (Ts), the concentration of CH3 ([CH3]) and the concentration of atomic H ([H]) can produce important effects on the film deposition rate and surface roughness.