Photoelectrochemical Degradation of Dye Pollutants Using Tio2 Thin Film Electrodes

Thin film electrodes were fabricated by immobilizing titanium dioxide (Ti02) onto titanium substrate using sol gel dip-coating method. The electrochemical technique was employed to study the photodegradation process on methyl orange dye. The effects of various parameters and conditions on electrochemical assisted photocatalytic degradation process were investigated by monitoring dyes decolourisation rates using UV-Vis spectrophotometer. Photosensitivity of the Ti02 thin film electrode was analysed by Linear Sweep Voltammetry (LSV) and Cyclic Voltamrnetry (CV) techniques combined with illumination. Sample heat-treated at 500°C showed the best photosensitivity. The TiOz thin films and the dried gel were also analysed using Scanning Electron Microscope (SEM), X-Ray Diffiactometry (XRD), UV/Vis Spectroscopy, Fourier Transform-Infra Red (FT-IR), Thennogravimetric Analyser (TGA), Differential Thermal Analyser (DTA) and CHNS analyser. The photoelectrochemical degradation experiment results showed that the rate of dye removal increased with external applied potential between 0.0 V and 1.5 V versus AgIAgCl reference electrode. Meanwhile, the photoeletrochemical degradation rate was also affected by initial concentrations, light intensity, light sources, photocatalysts coated area, repeated use, supporting electrolyte, solution pH, agitation and solution temperature. The photoelectrochemical degradation experiment was also camed out on naphtol blue black, rhodamine 6G, methylene blue, reactive blue 2, direct red 81, mixed dyes (consists of methyl orange, naphtol blue black, rhodamine 6G, methylene blue, reactive blue 2, direct red 8 1) and actual textile effluents. The removal efficiency was evaluated and compared in terms of UV/Vis decolourisation, Total Organic Carbon (TOC), Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD)

Photoelectrochemical reduction of aqueous protons with a CuO|CuBi2O4 heterojunction under visible light irradiation.

A p-type heterojunction photoelectrode consisting of platinized CuBi2O4 layered on a CuO film was prepared. The CuO|CuBi2O4|Pt electrode photo-generates H2 in pH neutral aqueous solution during visible light irradiation and exhibits a substantially enhanced photocurrent compared to CuO|Pt and CuBi2O4|Pt electrodes. Reduced electron-hole recombination by the band offsets in the heterostructure is responsible for the improved photoelectrochemical performance of CuO|CuBi2O4 with a small band-gap of approximately 1.5 eV.The work at Cambridge was supported by the Christian Doppler Research Association (Austrian Federal Ministry of Economy, Family and Youth and National Foundation for Research, Technology and Development), the OMV Group the EPSRC (EP/H00338X/2) and BBSRC (BB/K010220/1).This is the accepted manuscript version. The final published version is available from the RSC at http://pubs.rsc.org/en/Content/ArticleLanding/2014/CP/C4CP03883E#!divAbstract

Using two-tier bitwise interest oriented QRP data structure for high clustering through interest similarity in SWB P2P systems

The concept of “Small-World” paradigm has been used by many peer-to-peer (P2P) systems to achieve high clustering and low number of hops to arrive to its desired target. This approach intends to improve performance of P2P systems. The Small world concept requires that the architecture of a P2P system to achieve high cluster coefficient and low average hop between any two randomly chosen peers. In this research, we propose an enhanced hierarchical overlay network by incorporating the concept of Small world into the base hierarchical architecture. This research adopts the Query Routing Protocol (QRP) data structure of a hierarchical P2P network by storing the interest information of files in the leaf peers in the network. The QRP in the leaf peers will be aggregated and propagated to the SuperPeer so that interest information could be used to form short-range, medium-range and long-range links with other SuperPeers to achieve low average hop. As peers join and leave the network, a proposed rewiring protocol is used to ensure peers are clustered by interest to form high clustering coefficient so that search activities are yielding higher relevance results in a more predictable fashion. We simulated the porposed small world P2P using test scenarios to evaluate recall rate of the small world P2P system. Our simulated results evaluate and benchmark our proposed Small-World Bee (SWB) overlay network with iCluster [3], Firework Query Model [5] and Limewire [1] to assess performance obtained and goals achieved in the research work so that future research directions could be planned

Facile electrochemical synthesis of ultrathin iron oxyhydroxide nanosheets for the oxygen evolution reaction

We propose a facile approach to synthesise ultrathin iron oxyhydroxide nanosheets for use in catalysing the electrochemical oxygen evolution reaction. This two dimensional material lowers the overpotential and provides a platform for further performance enhancement via integration of species such as nickel into an ultrathin nanosheet structure

Enhancing mechanical properties of a low-carbon microalloyed cast steel by controlled heat treatment

In the present work, detailed studies were made on the optimization of microstructure and mechanical properties of a low-carbon microalloyed cast steel through control of heat treatment conditions. Specimens were austenitized at temperatures ranging from 950 to 1200 °C for 2 h followed by different cooling methods (furnace, air and water). For analyzing the effect of holding time on mechanical properties, some cast specimens were austenitized at 1100 °C for different times followed by furnace cooling. After heat treatment, mechanical tests were employed to evaluate the room temperature Charpy impact and tensile properties. The characterization of complex precipitates formed during heat treatment process was investigated by using analytical electron microscopy. The results show that dissolution of vanadium-containing precipitates plays an important role in the abnormal growth of austenite grains at 1150 °C. Further growth in austenite grains at 1200 °C is caused by the dissolution of Ti-containing particles and the reduction of the amount of precipitates. Correct selection of the austenitizing temperature, holding time and cooling method is very important to improve the mechanical properties of the steel. Heat treatment at 1100 °C for 2 h followed by furnace cooling leads to the best combination of excellent Charpy impact and tensile properties

Preparation and Evaluation of PEGylated and Folate-PEGylated Liposomes Containing Paclitaxel for Lymphatic Delivery

This study attempted to prepare polyethylene-glycol modified (PEGylated) and folate-PEGylated liposomes containing paclitaxel (Ptx) in order to reduce the toxicity and improve the bioavailability and biocompatibility by targeting drugs to the lymphatics using cancer cell specific ligand folate to prevent metastasis via the lymphatic system. Liposomes were prepared by lipid film hydration method using PEG and folate-PEG as surface modifiers. The mean particle size and encapsulation efficiency of liposomes were 114±6.81 nm and 81±2.3% for PEGylated liposome and 122±4.87 nm and 88±2.0% for folate-PEGylated liposome, respectively. According to stability test, it could be confirmed that PEGylated and folate-PEGylated liposomes were stable for at least 5 days. After intravenous administration of the PEGylated and folate-PEGylated liposomes to rats, the CLt (total clearance) and t1/2 (half-life) were significantly different (P<0.05) compared with those of PADEXOL Inj. In targeting efficiency, calculated as the concentration ratio of Ptx in lymph nodes and plasma, there was significant increase in targeting efficiency at lymph nodes (P<0.05). From these results, we could conclude that the prepared Ptx-containing PEGylated and folate-PEGylated liposomes are good candidates for the targeted delivery of the drug to lymphatic system

Prevalence of Inducible Clindamycin Resistance in Staphylococcal Isolates at a Korean Tertiary Care Hospital

Clindamycin resistance in Staphylococcus species can be either constitutive or inducible. Inducible resistance cannot be detected by the conventional antimicrobial susceptibility test. In this study, we determined the prevalence of inducible clindamycin resistance in staphylococcal isolates at a Korean tertiary care hospital. Between February and September 2004, 1,519 isolates of Staphylococcus aureus and 1,043 isolates of coagulase-negative staphylococci (CNS) were tested for inducible resistance by the D-zone test. Overall, 17% of MRSA, 84% of MSSA, 37% of MRCNS, and 70% of MSCNS were susceptible to clindamycin. Of the erythromycin non-susceptible, clindamycin-susceptible isolates, 32% of MRSA, 35% of MSSA, 90% of MRCNS, and 94% of MSCNS had inducible clindamycin resistance. Inducible clindamycin resistance in staphylococci was highly prevalent in Korea. This study indicates importance of the D-zone test in detecting inducible clindamycin resistance in staphylococci to aid in the optimal treatment of patients