This paper presents the development of an emissions-controlling technique for oil burners aimed especially to reduce oxides of nitrogen (NOx). Another emission of interest is carbon monoxide (CO). In this research, a liquid fuel burner is used. In the first part, five different radial air swirler blade angles, 30 degrees , 40 degrees , 45 degrees , 50 degrees , and 60 degrees , respectively, have been investigated using a combustor with 163 mm inside diameter and 280 mm length. Tests were conducted using kerosene as fuel. Fuel was injected at the back plate of the swirler outlet. The swirler blade angles and equivalence ratios were varied. A NOx reduction of more than 28% and CO emissions reduction of more than 40% were achieved for blade angle of 60 degrees compared to the 30 degrees blade angle. The second part of this paper presents the insertion of an orifice plate at the exit plane of the air swirler outlet. Three different orifice plate diameters of 35, 40, and 45 mm were used with a 45 degrees radial air swirler vane angle. The fuel flow rates and orifice plate's sizes were varied. NOx reduction of more than 30% and CO emissions reduction of more than 25% were obtained using the 25 mm diameter orifice plate compared to the test configuration without the orifice plate. The last part of this paper presents tests conducted using the air-staging method. An industrial oil burner system was investigated using the air staging method in order to reduce emission, especially NOx. Emissions reduction of 30% and 16.7% were obtained for NOx and CO emissions, respectively, when using air staging compared to the non-air-staging tests.
Biomedical research advances over the past two decades in bioseparation science and engineering have led to the development of new adsorbent systems called monoliths, mostly as stationary supports for liquid chromatography (LC) applications. They are acknowledged to offer better mass transfer hydrodynamics than their particulate counterparts. Also, their architectural and morphological traits can be tailored in situ to meet the hydrodynamic size of molecules which include proteins, pDNA, cells and viral targets. This has enabled their development for a plethora of enhanced bioscreening applications including biosensing, biomolecular purification, concentration and separation, achieved through the introduction of specific functional moieties or ligands (such as triethylamine, N,N-dimethyl-N-dodecylamine, antibodies, enzymes and aptamers) into the molecular architecture of monoliths. Notwithstanding, the application of monoliths presents major material and bioprocess challenges. The relationship between in-process polymerisation characteristics and the physicochemical properties of monolith is critical to optimise chromatographic performance. There is also a need to develop theoretical models for non-invasive analyses and predictions. This review article therefore discusses in-process analytical conditions, functionalisation chemistries and ligands relevant to establish the characteristics of monoliths in order to facilitate a wide range of enhanced bioscreening applications. It gives emphasis to the development of functional polymethacrylate monoliths for microfluidic and preparative scale bio-applications.
Three building complexes in Kuala Lumpur were surveyed for the presence of legionellae in cooling towers. The organisms were grown from 12 out of 46 samples of water collected from 30 towers. L. pneumophila serogroups 1 and 7 were the commonest serogroups isolated. None belonged to the Pontiac subgroup of L. pneumophila serogroup 1.
Between June 1977 and May 1982, 2,291 samples of raw, cooked and dried foods were examined for the presence of Salmonella. Of these samples, 43 were positive, isolations being made from raw foods (4.8%) and cooked foods (0.4%) but not from dried foods. 14 Salmonella seratypes were isolated, Salmonella anatum being the most predominant. The significance of these isolations is discussed and the need for consumer education to reduce the incidence of human salmonellosis is emphasised.
Considering its widespread usage in various fields, such as food, pharmaceutical, medical, cosmetic and polymer composites industries, microcrystalline cellulose (MCC) is becoming impellent due to increasing demand of alternatives to non-renewable and scarce fossil materials. Although it still suffers from some drawbacks, MCC has recently gained more interest owing to its renewability, non-toxicity, economic value, biodegradability, high mechanical properties, high surface area and biocompatibility. New sources, new isolation processes, and new treatments are currently under development to satisfy the increasing demand of producing new types of MCC-based materials on an industrial scale. Therefore, this review assembles the current knowledge on the isolation of MCC from different sources using various procedures, its characterization, and its application in bio-composites. Challenges and future opportunities of MCC-based composites are discussed as well as obstacles remaining for their extensive uses.
Raffaelea variabilis is described as a new species in culture from Lannea grandis. It is distinguished by turbinate to cuneiform conidia measuring 4-16 times 2.5-7.5 mum, and compared and contrasted with established species. Trichocladium lobatum is described as a new species in culture with 1-2 euseptate spherical conidia, 19-22 mum diam., ornamented with flabelliform, spathulate or petaloid lobes 7 mum long. It is compared and contrasted with established Trichocladium species and representatives of Chlamydomyces, Histoplasma, Mycogone, Sepedonium and Thermomyces.
Leptospirosis is a potentially life-threatening zoonosis caused by pathogenic Leptospira and for rapid diagnostics, direct detection is desirable. LipL32 protein is the most suitable biomarker for direct detection. DNA aptamers are sought to be generated against LipL32 by Systemic Evolution of Ligands via Exponential Enrichment (SELEX). LepDapt-5a is the most potent aptamer candidate among all the candidates, as determined by direct Enzyme-linked Aptasorbent Assay (ELASA). LepDapt-5a was predicted to form a G-quadruplex structure as predicted by QGRS Mapper and validated experimentally by direct ELASA. The diagnostic potential of the aptamer was further tested on a direct and sandwich ELASA platform. A LOD of 106 mL-1 and 105 mL-1 were estimated by direct and sandwich ELASA platforms, respectively, which are within the range associated with leptospiremia levels. The dot blot assay developed was able to attain a LOD of 104 CFU mL-1 against pathogenic Leptospira, which is also within the leptospiremia level. This is the first-ever DNA aptamer and hybrid-heterodimeric aptamer constructed against LipL32. The diagnostic potentiality of the LepDapt-5a DNA aptamer was proven on three major diagnostic platforms, which are direct ELASA, sandwich ELASA, and aptamer-based dot assay.
Detection of buried improvised explosive devices (IEDs) is a delicate task, leading to a need to develop sensitive stand-off detection technology. The shape, composition and size of the IEDs can be expected to be revised over time in an effort to overcome increasingly sophisticated detection methods. As an example, for the most part, landmines are found through metal detection which has led to increasing use of non-ferrous materials such as wood or plastic containers for chemical based explosives being developed.