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A novel zirconium-pillared montmorillonite (Zr-Mt) porous ceramic (P-ZMt) for Cr 3+ removal was developed by gelcasting. P-ZMt was characterized by XRD, SEM, XPS, TEM, BET. The influence of pH value, contact time, temperature and initial concentration on the adsorption efficiency was investigated. The results revealed that the P-ZMt has a high removal efficiency of Cr 3+ over a broad range of pH value. The pseudo-second-order kinetic model fitted our acquired Cr 3+ adsorption data best, in comparison with the pseudo-first-order kinetic model. The Langmuir model was applied to fit the adsorption process better than that of the Freundlich model. The thermodynamic parameters (∆H, ∆G and ∆S) were also determined, which revealed that the Cr 3+ adsorption process was spontaneous in nature. The present developed P-ZMt could be recovered and reused for more than 6 times. The novel developed P-ZMt is an inexpensive, effective and long-life-cycle adsorbent for Cr 3+ removal from water solution.

Gasoline Direct Injection (GDI) engines work with stratified charge at part load and burn with lean mixtures in order to save fuel, whilst at full load, the fuel and air mix homogeneously for maximum power output. The higher compression ratio and the absence of throttling are two of the most significant benefits of GDI engines. The key issues facing GDI combustion include in-cylinder mixture preparation and post-combustion soot formation. This work was intended to investigate these aspects and was undertaken on a dedicated Jaguar single-cylinder optical GDI engine with a spray-guided combustion system. The spray-guided concept does not rely as much on charge motion or piston design, and can avoid wall-wetting effects so as to reduce engine emissions. Relevant engine control hardware and data acquisition equipment were commissioned. Data/image processing software was also developed to suit the measurements. A data-processing case study with data from a small two-stroke glow ignition engine has been conducted to develop a method to combine the burn rate and heat release analyses in the study of engines with premixed charge but compression ignition. Difficulties such as unknown ignition timing and polytropic index have been addressed. Results for all operating conditions have shown good correlations between the two methods. The technique of quantitative planar laser-induced fluorescence is useful for measuring 2-D fuel distribution in GDI engines. The relevant physics and literature were reviewed in depth. A multi-component fuel was designed to give reasonable co-evaporation characteristics with tracers matching different fuel fractions. The absorption and fluorescence features of each fuel component and tracer were characterised. Optimisation of hardware and signal-to-noise ratio was performed. A recirculating loop was set up for the calibration of the technique. The technique of colour-ratio pyrometry (CRP) for estimating the temperature and loading of soot was applied on the GDI engine. Critical features of the candidate CCD colour camera including its spectral response and noise behaviours were fully studied. Validation tests with reference sources together with an error analysis suggested an accuracy of ±50K within the combustion temperature range. Engine combustion images were then taken under various operating conditions. Temperature estimates were shown to be insensitive to the concentration of soot. Simulation with a thermodynamic modelling package, ISIS, was introduced for comparison with the experimental data. With careful tuning, ISIS gave outputs comparable to the CRP and proved to be a cost-effective tool to study GDI engines. High-speed combustion imaging was carried out using a CMOS camera, allowing the study of flame properties as well as crank-angle resolved CRP. By using a lens in the piston crown to give full bore optical access and appropriate image processing, the flame front could be detected reliably throughout the main combustion process.

A simulated experiment exposing Corbicula fluminea in the Cd contaminated sediment of Lake Taihu was conducted in laboratory to study the bioaccumulation of Cd in Corbicula fluminea and the distribution regularity of Cd in water.The speciation of Cd extracted by DGT and BCR and the releasing regularities were determined in sediments of Lake Taihu to obtain the applicability of predicting sediment quality guidelines.When the contaminated concentration increased,the concentration of Cd extracted by DGT and BCR in overlying water and accumulated in Corbicula fluminea increased.The results showed that the content of Cd in Corbicula fluminea was significantly correlated with the results measured by two methods after 14 days and 28 days exposure.It offered theoretical statistics for the prediction of sediment quality guidelines of Cd.

In the last years, an increasing attention has been devoted to the utilization of anodic oxidation (AO) technologies for the treatment of wastewater polluted by recalcitrant organics. Recently, Ti4O7 was proposed as a promising anode for AO for the treatment of various organics. Here the potential utilization of commercial Ti4O7 anodes has been evaluated considering the electrochemical treatment of synthetic wastewater contaminated by three very different organic molecules (namely, oxalic acid, phenol and Acid Orange 7), all characterized by a very high resistance to AO. The performances of Ti4O7 were compared with that of two largely investigated anodes: Boron-doped diamond (BDD), which is probably the most effective electrode for AO, and an Ir-based anode which presents a relatively low cost. Moreover, the effect of various operative conditions (current density, mixing rate and initial concentration of the organic) was evaluated by both experimental studies and the adoption of a theoretical model previously developed for BDD anodes. It was shown that the performances of the process can be improved by a proper selection of operative conditions. Moreover, it was found that the proposed model can be effectively used to predict the effect of operative parameters at Ti4O7 anodes, thus helping the process optimization.