ISO 9000 and beyond: from a Hong Kong construction perspective

Client driven ‘pushes’ for ISO 9000 certification in Hong Kong are observed to have overtaken any spontaneous ‘pull factors’ (motivators) towards quality improvements ‘for their own sake’. For example, the need for ISO 9000 certification as a prerequisite for even being considered for public sector construction works appears to have distracted some organizations from a more comprehensive organization-specific development of their quality management systems. Both positive (beneficial) and negative (detrimental) outcomes from ISO 9000 certification, as observed from relevant previous studies, are summarized herein. These provide a useful background against which to present perceptions derived from the current study in Hong Kong construction. The target groups were predominantly from consultants in the initial survey and all from contractors in the second and more comprehensive survey. The more significant positive and negative outcomes from ISO 9000 certification as derived from the two current surveys are identified. Recommendations are made for realigned approaches to ISO 9000 certification and for seamless integration with other quality management approaches such as TQM, as well as with other management subsystems, such as for productivity improvement and dispute minimization.     

Differential responses to blood pressure and oxidative stress in streptozotocin-induced diabetic wistar-kyoto rats and spontaneously hypertensive rats: effects of antioxidant (honey) treatment

Oxidative stress is implicated in the pathogenesis and/or complications of hypertension and/or diabetes mellitus. A combination of these disorders increases the risk of developing cardiovascular events. This study investigated the effects of streptozotocin (60 mg/kg; ip)-induced diabetes on blood pressure, oxidative stress and effects of honey on these parameters in the kidneys of streptozotocin-induced diabetic Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR). Diabetic WKY and SHR were randomized into four groups and received distilled water (0.5 mL) and honey (1.0 g/kg) orally once daily for three weeks. Control SHR had reduced malondialdehyde (MDA) and increased systolic blood pressure (SBP), catalase (CAT) activity, and total antioxidant status (TAS). SBP, activities of glutathione peroxidase (GPx) and glutathione reductase (GR) were elevated while TAS was reduced in diabetic WKY. In contrast, SBP, TAS, activities of GPx and GR were reduced in diabetic SHR. Antioxidant (honey) treatment further reduced SBP in diabetic SHR but not in diabetic WKY. It also increased TAS, GSH, reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio, activities of GPx and GR in diabetic SHR. These data suggest that differences in types, severity, and complications of diseases as well as strains may influence responses to blood pressure and oxidative stress.     

Gentamicin‐loaded poly(acrylic acid)‐grafted cotton fibers,part 1: Synthesis,characterization, and preliminary drug release study

This study describes preparation of poly (acrylic acid)‐grafted cotton fibers and release of antibiotic drug gentamicin sulfate from them under physiological conditions. Poly(acrylic acid) has been grafted onto cellulose backbone of cotton fibers via Ce(IV)‐initiated polymerization in aqueous medium. The conditions obtained for optimum grafting were as follows: initiation time 30 min; initiation temperature 37°C; monomer concentration 27.8 mM; grafting temperature 30°C; nitric acid (catalyst) concentration 0.1M. The grafted fibers were characterized by FTIR, TGA, and SEM analysis. The antibiotic drug gentamicin sulfate (GS) was loaded into the grafted fibers by equilibration method and release was studied under physiological conditions. The kinetic release data was interpreted by first‐order kinetic model. Finally, drug‐loaded fibers showed fair antibacterial action against Escherichia coli. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Electron beam (EB) radiation curing—a unique technique to introduce mixed crosslinks in cured rubber matrix to improve quality and productivity

Effect of electron beam (EB) pretreatment on tire components has been investigated. The technique proved to be incredibly useful for reducing curing time of thick rubber products in the press and enhancing or retaining the properties required by a tire. This unique technique can be use to incorporate mixed crosslink in rubber products. Investigations were performed both on experimental compounds and industrial compounds. Experimental compound study was limited to development of theoretical data, effect of particular ingredients on EB radiation curing, and evaluating optimum dose required for obtaining optimum properties and reduction in cure time. The same sequence of study was followed on the compounds of tire components obtained from a reputed tire manufacturer. Components of tire such as inner liner and tread were irradiated with optimum doses selected in line with the study conducted on the experimental and industrial compounds. These components were then used to build the green tire. Properties of compound and tire as a whole were checked and are reported in detail in the article. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Biotransformation of CI Acid Blue 113 and other dyes by Shewanella sp. P6

The isolate P₆, an indigenous Shewanella sp., was able to decolorise 90% of CI Acid Blue 113 in just 30 min of incubation under anoxic conditions. The decolorisation potential of cells was not significantly affected even in the presence of 2% (w/v) sodium chloride and 8% (w/v) sodium sulphate. Mass spectrometric analysis detected the formation of aniline sodium salt, 1,4‐diaminonaphthalene, 5‐amino‐8‐(phenylamino)‐naphthalene‐1‐sulphonic acid sodium salt and 8‐(phenylamino)‐naphthalene‐1‐sulphonic acid sodium salt. Further, cells of P₆ decolorised the raw effluent collected from the equalisation tank of a textile industry wastewater treatment plant. The water‐soluble dyes/intermediates present in the sludge, generated after chemical flocculation of raw effluent, were transformed by P₆ cells within 24 h of incubation under anoxic conditions. Thus, isolate P₆ has a potential application in the biological treatment of liquid and solid waste of textile processing plants because of its efficient decolorisation and transformation properties.     

Wide range fully integrated VCO with new cells-based varactor

This article presents a wide range inductance–capacitance voltage controlled oscillator (VCO) with a unit cells-based varactor. The unit cell represents the minimum possible integrated varactor based on p–n junction diodes, where N⁺ diffusions are central rectangles, surrounded by doughnut shaped P⁺ diffusions, with their respective contacts. The varactors are designed using the AMS 0.35?µm BiCMOS process. A physical model has been derived from the measurement of a set of eight fabricated varactors. Measurements indicate that the VCO, which is intended to be used in DVB-H, oscillates from 1.087 to 2.032?GHz, with a 61% tuning range. The phase noises of ?124?dBc/Hz at 1?MHz offset and ?108?dBc/Hz at 100?kHz offset are obtained.     

Comparative Study on the Role of DPT on the Formation of HMX in Semi-Batch and Continuous Process

3,7-Dinitro-1,3,5,7-tetrazabicyclo-[3,3,1]nonane (DPT) is a key intermediate in the preparation of octahydro-1,3,5,7-tetranitro 1,3,5,7-tetrazocine (HMX), one of the most powerful high-melting explosives. The present investigation focuses on DPT formation during semi-batch and continuous processes. Qualitative and quantitative picture has been brought out to realize the role of DPT in HMX formation. The study reveals that only two thirds of DPT is formed in the continuous process as compared to that of semi-batch process. The calculated final yield of HMX on reaching steady state in the continuous process is comparable to the semi-batch process. This study also illustrates the usefulness in understanding the role of DPT in the final yield of HMX.     

Influence of temperature on multiaxial creep behaviour of 304HCu austenitic stainless steel

Effect of temperature on multiaxial creep behaviour of 304HCu austenitic stainless steel has been investigated. The multiaxiality was introduced by incorporating notches in smooth specimens. Creep rupture life increased with notch acuity ratio having a saturation/decline tendency. Notch strengthening increased with temperature, stress and notch sharpness. Multiaxial ductility decreased rapidly with notch sharpness and tended towards saturation. Fracture mode was found to change from transgranular ductile to intergranular creep depending on the stress, temperature and notch sharpness. Finite element analysis of notched specimens along with orientation imaging microscopic study was carried out to assess the deformation and damage at different normalised stress ratio. A temperature independent unique master plot for multiaxial rupture life as a function of stress has been established.     

Role of biomineralization on the degradation of fine grained AZ31 magnesium alloy processed by groove pressing

Groove pressing (GP) has been successfully adopted to achieve fine grain size up to 7 μm in AZ31 magnesium alloy with an initial grain size of 55 μm. The effect of microstructural evolution and surface features on wettability, corrosion resistance, bioactivity and cell adhesion were investigated with an emphasis to study the influence of deposited phases when the samples were immersed in simulated body fluid (SBF 5 ×). The role of microstructure was also evaluated without any surface treatments or coatings on the material. GPed samples exhibit improved hydrophilicity compared to the annealed sample. After immersion in SBF, specimens were characterized using scanning electron microscopy (SEM), energy dispersive X-ray (EDAX) analysis and X-ray diffraction (XRD) methods. More amount of white precipitates composed of hydroxyapatite and magnesium phosphate along with magnesium hydroxide was observed on the surfaces of groove pressed specimens as compared to the annealed specimens with an increase in immersion time in SBF. Corrosion behavior of the samples estimated using potentiodynamic polarization curves indicate good corrosion resistance for GPed samples before and after immersion in SBF. The MTT assay using rat skeletal muscle (L6) cells revealed that both the processed and unprocessed samples are nontoxic and cell adhesion was promising for GPed sample.     

Damage evolution in glass/epoxy composites engineered using core–shell microparticles under impact loading

The overall objective of the investigation presented in this paper was to study the effect of dispersion of core–shell polymer (CSP) particles within the ply interfaces on damage evolution of glass/epoxy laminates under impact loading. These laminates were fabricated with the CSP particle dispersion controlled to 14 % of the total weight of the used prepreg. A series of impact experiments were done with instrumental drop tower device at all probable impact energies within a practical low velocity impact range. The damage phenomena occurring in the internal microstructure of the laminates were analysed with the help of scanning electron microscope and correlated to the structural response of the laminate. The predominant damage modes were dependent on the magnitude of the applied impact energy. The CSP particle incorporation does not change the sequence of the fracture events but it delays and mitigates the damage creation. The deformation of the CSP particles and the tearing of their outer shells absorb most of the impact energy thereby preventing initiation of matrix cracks at lower impact energies and delaying fibre damage at higher energies. The crushed particles along with their nano-size rubber cores impede crack propagation requiring the cracks to follow torturous paths consequently dissipating additional amount of energy. These particles also promote elastic energy absorption of the laminates minimizing their tendency to fracture easily under impact. The ultimate load bearing capability of the modified laminate showed 60 % improvement and the deflection characteristics indicated lower proneness to impact.