Reproducibility Performance Test of Multi Metal Oxide Catalyst in Selective Oxidation of Propane using Combinatorial Technology

The concept of rapid catalyst screening using combinatorial technology was applied in the development of selective oxidation catalyst. In this paper, the design, Design of Experiment (DOE) and catalytic results are discussed to demonstrate the importance and versatility of such technology. The instrument is implaced in COMBICAT (Universiti Malaya) to rapidly support parallel testing of catalytic material using continuous fixed bed reactor technology programme. It is used for the automated parallel testing of selective oxidation of propane to acrylic acid over some types of multi metal oxide catalysts. The configuration of the ‘nanoflow’ is shown to be suitable to screen catalytic performance, and its operating conditions were mimicked closely to conventional laboratory as well as to industrial conditions. The results obtained gave very good reproducibility

A Novel Solar Driven Photocatalyst: Well-Aligned Anodic WO3 Nanotubes

Well-aligned anodic tungsten trioxide (WO3) nanotubes were successfully synthesized by anodization of W foil at 40V in a bath with electrolyte composed of 1M of sodium sulphate (Na2SO4) and 0.5 wt% ammonium fluoride (NH4F). The effect of electrochemical anodization times on the formation mechanism of anodic WO3 nanotubular structure was investigated. It was found that minimumof 15 min is required for completing transformation fromWfoil toWO3 nanotubular structurewith an average diameter of 50nmand length of 500 nm.Thephotocatalytic ability of the sampleswas evaluated by degradation of methyl blue (MB) dye.Theresults indicate that the surface morphology of anodicWO3 affected the photocatalyticMBdegradation significantly under solar illumination

Optimization of reaction parameters in hydrothermal synthesis: a strategy towards the formation of CuS hexagonal plates

BACKGROUND: For decades, copper sulphide has been renowned as the superior optical and semiconductor materials. Its potential applications can be ranged from solar cells, lithium-ion batteries, sensors, and catalyst systems. The synthesis methodologies of copper sulphide with different controlled morphology have been widely explored in the literature. Nevertheless, the understanding on the formation chemistry of CuS is still limited. The ultimate approach undertaking in this article is to investigate the formation of CuS hexagonal plates via the optimization of reaction parameters in hydrothermal reaction between copper (II) nitrate and sodium thiosulphate without appending any assistant agent. RESULTS: Covellite (CuS) hexagonal plates were formed at copper ion: thiosulphate ion ([Formula: see text]) mole ratio of 1:2 under hydrothermal treatment of 155°C for 12 hours. For synthesis conducted at reaction temperature lower than 155°C, copper sulphate (CuSO(4)), krohnite (NaCu(2)(SO(4))(H(2)O)(2)] and cyclooctasulphur (S(8)) were present as main impurities with covellite (CuS). When [Formula: see text] mole ratio was varied to 1: 1 and 1: 1.5, phase pure plate-like natrochalcite [NaCu(2)(SO(4))(H(2)O)] and digenite (Cu(9)S(5)) were produced respectively. Meanwhile, mixed phases of covellite (CuS) and cyclooctasulphur (S(8)) were both identified when [Formula: see text] mole ratio was varied to 1: 2.5, 1: 3 and 1: 5 as well as when reaction time was shortened to 1 hour. CONCLUSIONS: CuS hexagonal plates with a mean edge length of 1 μm, thickness of 100 nm and average crystallite size of approximately (45 ± 2) nm (Scherrer estimation) were successfully synthesized via assisting agent- free hydrothermal method. Under a suitable [Formula: see text] mole ratio, we evidenced that the formation of covellite (CuS) is feasible regardless of the reaction temperature applied. However, a series of impurities were attested with CuS if reaction temperature was not elevated high enough for the additional crystallite phase decomposition. It was also identified that [Formula: see text] mole ratio plays a vital role in controlling the amount of cyclooctasulphur (S(8)) in the final powder obtained. Finally, reaction time was recognized as an important parameter in impurity decomposition as well as increasing the crystallite size and crystallinity of the CuS hexagonal plates formed

Progress on antimicrobial surgical gloves: A review

Surgical gloves provide a protective blockade for patients and members of the surgical team. Glove integrity is critical in an era of blood-borne pathogens. Therefore, the need for improved means for prevention and also gloving and appropriate hand hygiene in a hospital setting is ostensible. This perspective highlights the progress on antimicrobial surgical gloves in deducting the microbial passage after a glove puncture in a model of wound contamination. Moreover, traditional methods to avoid microbes in the hospital and various antimicrobial agents, such as metal ions and antiseptic dyes, are reviewed

Mechanism and Kinetics Study for Photocatalytic Oxidation Degradation: A Case Study for Phenoxyacetic Acid Organic Pollutant

Photocatalysis is a rapidly expanding technology for wastewater treatment, including a wide range of organic pollutants. Thus, understanding the kinetics and mechanism of the photocatalytic oxidation (PCO) for degradation of phenoxyacetic acid (PAA) is an indispensable component of risk assessment. In this study, we demonstrated that the central composite design (CCD) coupled with response surface methodology (RSM) was successfully employed to probe the kinetics and mechanism of PCO degradation for PAA using an efficient zinc oxide (ZnO) photocatalyst. In our current case study, four independent factors such as ZnO dosage, initial concentration of PAA, solution pH, and reaction time on the PCO degradation for PAA were examined in detail. Based on our results obtained from RSM analyses, an efficient pathway leading to the high degradation rate (>90%) was applying 0.4 g/L of ZnO dosage with 16 mg/L of concentration of PAA at pH 6.73 for 40 minutes. The experimental results were fitted well with the derived response model with R2 = 0.9922. This study offers a cost-effective way for probing our global environmental water pollution issue

Identification of short-length oligonucleotides biomarker for canine species detection using mitochondrial cytochrome b gene

Introduction: Stray dogs are still available in certain countries without any offered price and made it as a potential source for adulteration with costly meats for more benefit. Furthermore, human forensic evidences from crime scenes were often integrated with biomaterial of canine origin. Most of the DNA based assay for canine species detection used longer amplicon size (>150 bp) which are not suitable for highly degraded food or forensic sample analysis. Therefore, in this study for development of short length canine specific biomarker, mitochondrial cytochrome b (cytb) gene was targeted using simple PCR assay. Objective: Detection of canine species using short length DNA biomarker targeting cytb gene. Methods: The assay targeted a 100-bp fragment of cytochrome b gene using a pair of canine specific primers. The primers specificity were tested under Insilco, as well as in real PCR assay using dog and eight other species DNAs. The consensus 100 bp canine specific site along with cytb sequences of 14 species including dog and human were used for analysis of pair wise distances, construct dendogram and primers mismatch calculation. The stability of the biomarker was tested under commonly used cooking condition and extensive autoclaving state which was known for degradation of target DNA. The sensitivity of the assay was tested using binary admixture composed of dog and most consumed chicken DNA pool. Results & Discussion: The biomarker was 100% canine specific and successfully amplified 100 bp region of canine cytb gene specific target. It was highly stable and sensitive enough to detect as low as 0.1% (0.02 ng) of canine specific target from admixed DNAs. Conclusion: The primers provided the shortest DNA biomarker for canine species detection. The shortest amplicon length, high stability and sensitivity offered its potentiality for canine biomaterials determination from food as well as from degraded samples

Synthesis and characterization of nickel ferrite magnetic nanoparticles by co-precipitation method

Magnetic nickel ferrite (NiFe2O4) nanoparticles have been synthesized via co-precipitation method by varying the metal precursors ratio. Four different precursors ratio (Fe:Ni) are varied at 40:60, 50:50, 60:40 and 80:20. The size of the nanoparticles is found to increase with increasing iron (Fe) content. In addition, the morphology of the particles are observed to change from spherical to a shape similar to a nanooctahedral particle when the Fe content in the initial precursors ratio increases. The X-ray Diffraction (XRD) patterns have proved the presence of nickel ferrite nanoparticles. The magnetic properties characterized by Vibrating Sample Magnetometer (VSM) at room temperature proved that the assynthesized nickel ferrite nanoparticles are ferromagnetic and the saturation magnetization (Ms) increases with the content of Fe in the sample

A Suitable method to detect potential fraud of bringing Malayan box turtle (Cuora amboinensis) meat into the food chain

Malayan box turtle (Cuora amboinensis) has been a wildlife-protected vulnerable turtle species in Malaysia since 2005. However, because of its purported usage in traditional medicine, tonic foods and feeds, clandestine black market trade is rampant. Several polymerase chain reaction (PCR) assays for the taxonomic detection and classification of turtle species have been proposed. These assays are based on long-length target amplicons which are assumed to break down under compromised states and, hence, might not be suitable for the forensic tracing and tracking of turtle trafficking. For the first time this paper develops a very short-amplicon-length PCR assay (120 bp) for the detection of Malayan box turtle meat in raw, processed and mixed matrices, and experimental evidence is produced that such an assay is not only more stable and reliable but also more sensitive than those previously published. We checked the assay specificity against 20 different species and no cross-species detection was observed. The possibility of any false-negative detection was eliminated by a universal endogenous control for eukaryotes. The assay detection limit was 0.0001 ng of box turtle DNA from pure meat and 0.01% turtle meat in binary and ternary admixtures and commercial meatballs. Superior target stability and sensitivity under extreme treatments of boiling, autoclaving and microwave cooking suggested that this newly developed assay would be suitable for any forensic and/or archaeological identification of Malayan box turtle species, even in severely degraded specimens. Further, in silico studies indicated that the assay has the potential to be used as a universal probe for the detection of nine Cuora species, all of which are critically endangered

TiO2 nanotubes supported Cu nanoparticles for improving photocatalytic degradation of simazine under UV illumination

Nano size Copper (Cu) incorporated TiO2 nanotubes was successfully synthesized via the anodic oxidation technique in ethylene glycol (EG) containing 0.5 wt % NH4F and 1.6 wt % KOH for the photocatalytic degradation of Simazine (2-chloro-4, 6-diethylamino-1,3,5-triazine) under Ultraviolet (UV) illumination. In the present study, the influence of different loading Cu concentrations on the formation of Cu-TiO2 nanotubes film towards the photocatalytic degradation of Simazine is reported. Based on our study, it was found that the optimum Cu loading concentration was about 0.45 wt % on TiO2 nanotubes film for approximately 64% photocatalytic degradation of Simazine after 4 h under UV illumination. This finding was mainly attributed to the uniform surface covering of the Cu loaded TiO2NTs which acted as electron traps, preventing the recombination of electron hole pairs, eventually leading to higher photocatalytic activity of our photocatalyst in degrading the targeted organic pollutant, Simazine. Moreover, an increased kinetic rate of the degradation to 0.0135 h−1 was observed in the presence of Cu in TiO2NTs