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Yellow mealworm (Tenebrio Molitor) was reported containing 24.3 to 27.6% protein content. However, public acceptance is still relatively low as many tend to reject it as a source of food. Hence, studies were carried out to incorporate dried mealworm powder into a standard butter cake mixture formulation. Yellow mealworms were dried using an air ventilated oven at 80°C. The dried mealworms were then ground into powder and added in a standard butter cake formulation (0%, 5% and 10%). Baking was carried out in a convective oven at 140°C for 30 minutes. Moisture content, colour, texture and protein content were analysed. The effective diffusivity values of the cake samples varied from 4.46 × 10-11 m2/s to 4.72 × 10-11 m2/s. Significant observations were recorded for the L * and b * values obtained among the cake samples. The firmness of the cake increased while the springiness decreased as addition of the mealworm powder was increased. An increase in protein content was observed from 5.99% to 11.12% with the addition of mealworm powder in the cake formulation.

We report a dual-micropump structure operated by a single actuator element. The constituent micropumps are a form of micro throttle pump (MTP) comprising a narrow flow channel incorporating two microthrottles. We term this a 'linear MTP' (LMTP). The LMTP's narrowness, in conjunction with an elastomeric substrate, allows multiple, independent, LMTPs to be actuated by a single piezoelectric actuator thereby suiting it to parallel microfluidic architectures. Furthermore, LMTP elements can be combined into parallel or series composites yielding increased maximum pumping rates or back pressures, respectively, when compared to a single LMTP element. The LMTP's flow-channel-like, linear pump chamber minimizes the development of recirculatory flows associated with circular pump chambers which, in part, determine their frequency response and hence maximum pumping rates. We have modelled, fabricated and evaluated a dual-LMTP. We report operation in three modes: as two distinct pumps, as a series composite pump, and as a parallel composite pump. Operating at about 1.6 kHz, with both pumps under identical load conditions, each pump yielded maximum pumping rates of about 750 µl min−1 and back pressures of 18 kPa, both with close matching. Configured as a series composite, a 35 kPa back pressure was achieved, and configured as a parallel composite, a maximum pumping rate of 1.4 ml min−1 resulted. Images of 5 µm polystyrene beads flowing within an LMTP confirm minimal recirculatory behaviour consistent with the LMTP's increased operating frequencies compared to circular pump chamber MTPs.

We report a self-contained microfluidic alternate flow injection mixer (AFIM) employing piezoelectrically actuated, PDMS seal-valves to control injection. AFIMs employ pulsatile injection of liquids to enhance interface surface generation. By allowing control of pulse-volume proportionality by variation of the duty-cycle of the valve control signals, continuously variable ratio mixing is achieved without external fluid control components. Mixing is discussed in the context of 'rate of new surface generation', thus allowing comparison with laminating mixer designs. The prototype mixer employs a simple micromould fabrication technique to minimize reversible elastomer valve-seal adhesion and hence allow correct valve operation. The resulting device has been characterized over a range of mixing ratios.

We report a micro throttle pump (MTP) with enhanced throttling resulting from beneficial deformation of its elastomer substrate. In the MTP reported, this has doubled the effective deflection of the piezo electric (PZT) actuator with a consequent five-fold enhancement of throttling ratio. This mode of throttling has been modelled by finite element method and computational fluid dynamic techniques whose predictions agreed well with experimental data from a throttle test structure; providing typical throttling ratios of 8:1 at low pressures. The improved throttles have been incorporated in a prototype, single PZT, MTP, fabricated with double-depth microfluidics, which pumped both water and a suspension of 5 µm polystyrene beads at a maximum flow rate of 630 µl min−1 and a maximum back-pressure of 30 kPa at a pumping frequency of 1.1 kHz. This represents an approximate five-fold enhancement of both performance metrics compared to our previous single PZT device.

Quality control is crucial in a wide variety of fields, as it can help to satisfy customers' needs and requirements by enhancing and improving the products and services to a superior quality level. The EWMA median chart was proposed as a useful alternative to the EWMA chart because the median-type chart is robust against contamination, outliers or small deviation from the normality assumption compared to the traditional -type chart. To provide a complete understanding of the run-length distribution, the percentiles of the run-length distribution should be investigated rather than depending solely on the average run length (ARL) performance measure. This is because interpretation depending on the ARL alone can be misleading, as the process mean shifts change according to the skewness and shape of the run-length distribution, varying from almost symmetric when the magnitude of the mean shift is large, to highly right-skewed when the process is in-control (IC) or slightly out-of-control (OOC). Before computing the percentiles of the run-length distribution, optimal parameters of the EWMA median chart will be obtained by minimizing the OOC ARL, while retaining the IC ARL at a desired value.

In this paper, SU-8 EPON-based photoresist (PR) polymerization optimization and its possible microfluidic and MEMS applications are reported. First, the optimization results of SU-8 under UV lithography are reported. The parameters which could have an influence on the lithography quality were chosen and optimized by a three-level, L9 orthogonal array of the Taguchi method. By optimization, the optimal parameter range and the weighted per cent of a parameter on the final results were determined. For SU-8-5 and SU-8-50, many microstructures with thicknesses of more than 100 and 500 µm and aspect ratios of more than 20 and 50 were obtained with high resolution. The optimization results show that the prebake time plays the key role in the quality, which is different from the previously published results. With the optimization results obtained, some possible applications of SU-8 were developed and demonstrated. These applications included using SU-8 as a structural material for a microfluidic system, as a micromold for electroplating, as a master for plastic hot-embossing, and even as a mask for some wet-etching processes.

Angle-resolved x-ray photoelectron spectroscopy (ARXPS) has been used to study surface compositional changes in GaAs (100) as a consequence of 1 to 5 keV ion bombardment. Prior to ion bombardment, the ARXPS measurements showed that neglecting surface contamination, the composition of the GaAs surface was close to its stoichiometric value of 1:1. After ion bombardment, the oxide layer was efficiently removed. At steady state the altered layers induced by 1 - 5 keV ion bombardment were, on average, Ga-rich up to the sampling depth of the ARXPS technique. The ARXPS measurements also showed that the depth profile of the altered layer was a function of ion energy. The altered layer induced by 1 keV ion bombardment was inhomogeneous as a function of depth and appeared richer in Ga on the surface than in the subsurface region, that by 3 keV ion bombardment was homogeneous and that by 5 keV ion bombardment was less Ga-rich on the surface than in the subsurface region. The results are discussed in the context of preferential sputtering, radiation-enhanced diffusion/segregation, and altered layer thickness dependence on ion energy.

Ion beam nitridation (IBN) of InP at room temperature was studied as a function of both ion incident angle and energy. The InP surfaces were exposed to ion beam in an ultrahigh vacuum environment and the resulting surfaces were characterized in situ by small spot size x-ray photoelectron spectroscopy (XPS) for accurate determination of the surface composition and chemical state. Thin InN reaction layers were formed at all ion incident angles and ion energies whereas the formation of P - N bonds was not observed. However, the degree of nitridation of In decreases with increasing incident angle and ion energy, closely following the reduced incorporation of N at higher angles and ion energies. The variation in nitridation is smaller with ion energy in the 2 - 10 keV range than with ion incident angle. The observed angular and energy dependence of the N incorporation can be explained in terms of sputtering yields, indicating that the growth kinetics can be described as a dynamic process comprising the accumulation of N and sputter removal of the surface layer.

Fast-anion-conducting glasses in the system xPbF2:(1-x)B2O3 have been synthesized and analysed by thermal, electrical and spectroscopic techniques. The ionic conductivity ( sigma ) of these glasses is measured as a function of temperature and chemical composition by the complex impedance method and the results indicate that the conduction of fluorine as charge carriers is governed by activation energy alone. Infrared and X-ray photoelectron spectroscopy studies have provided evidence for fluorine participation in the berate network. Further, the compositional dependence of X-ray photoelectron F 1s spectra indicates that fluorine is incorporated predominantly as B-O-F and Pb-O-F bonds in the oxide network at high B2O3 and PbF2 content respectively. The spectroscopic results obtained are discussed in relation to anionic conduction.

Surface and optical analytical techniques of x-ray photoelectron spectroscopy, Auger electron spectroscopy, secondary ion mass spectrometry, Fourier transform infrared transmission, photoluminescence and Raman scattering have been used to study porous Si membranes with visible light emission. The main components of surface layers were found to be SiO2 plus Si clusters and some contamination elements. The depth distributions of these impurities over the entire 200 mu m thick membrane were also profiled. Porous Si membranes show a large number of infrared active modes due to the oxidized and organized surfaces of the pores. Their Raman features are markedly distinct from that of crystalline, microcrystalline and amorphous Si. Their anomalous Raman temperature behaviour is explained by the quantum wire model and strain effects. The combination of surface and optical analyses offers better understanding for the properties of porous Si.

Polydimethylsiloxane (PDMS) elastomers are extensively used for soft lithographic replication of microstructures in microfluidic and micro-engineering applications. Elastomeric microstructures are commonly required to fulfil an explicit mechanical role and accordingly their mechanical properties can critically affect device performance. The mechanical properties of elastomers are known to vary with both curing and operational temperatures. However, even for the elastomer most commonly employed in microfluidic applications, Sylgard 184, only a very limited range of data exists regarding the variation in mechanical properties of bulk PDMS with curing temperature. We report an investigation of the variation in the mechanical properties of bulk Sylgard 184 with curing temperature, over the range 25 ◦ C to 200 ◦ C. PDMS samples for tensile and compressive testing were fabricated according to ASTM standards. Data obtained indicates variation in mechanical properties due to curing temperature for Young’s modulus of 1.32‐2.97 MPa, ultimate tensile strength of 3.51‐7.65 MPa, compressive modulus of 117.8‐186.9 MPa and ultimate compressive strength of 28.4‐51.7 GPa in a range up to 40% strain and hardness of 44‐54 ShA.

The launch of the National Green Technology Policy (NGTP) in 2009 is a manifesto of the government's seriousness in implementing "green" initiatives for the country. Specifically for buildings, the government promotes the application of renewable energy (RE) and energy efficiency (EE) and the application of green building index. With the introduction of Low Carbon Cities Framework, Green Pass, Green Neighbourhood, Green Building Index by various agencies and organisations in Malaysia, it is time to look back and see how all these tools could come together. This paper attempts to identify the challenges in harmonising the green initiatives for policy makers toward greener environment for sustainability.

The objective of this study is to investigate empirically the extent to which self-efficacy contributes to the development of green entrepreneurial intention. The measurement constructs of self-efficacy were classified into market opportunities, innovative environment, initiating relationships, defining purpose, coping with challenges, and developing human resources. The study comprises 252 usable convenient samples through structured questionnaires. The coefficient of determination R2 shows that the variance of intention to entrepreneurship is explained by the variance of the independent variables. It was also found that the model is fit for prediction.

Fluid transport is accomplished in a micro throttle pump (MTP) by alternating deformation of a micro channel cast into a polydimethylsiloxane (PDMS) elastomeric substrate. The active deformation is achieved using a bimorph PZT piezoelectric disc actuator bonded to a glass diaphragm. The bimorph PZT deflects the diaphragm as well as alternately pushing and pulling the elastomer layer providing displacement amplification in the PDMS directly surrounding the micro channel. In order to improve pumping rates we have embedded a polymethylmethacrylate (PMMA) ring into the PMDS substrate which increases the magnitude of the displacement amplification achieved. FEM simulation of the elastomeric substrate deformation predicts that the inclusion of the PMMA ring should increase the channel deformation. We experimentally demonstrate that inclusion of a PMMA ring, having a diameter equal to that of the circular node of the PZT/glass/PDMS composite, increases in the throttle resistance ratio by 40% and the maximum pumping rate by 90% compared to an MTP with no ring.

A low-cost Helmholtz resonator system is described. The system is simple to construct and yet yields high quality absorption line shapes and a value for the velocity of sound accurate to within 1%. The experiment should be a welcome addition to an under-graduate laboratory where there is a general lack of acoustics experiments and in particular precision measurement of acoustic parameters.

Experimental results showing PCI in the decay of the Ne K hole following electron excitation are presented. PCI is shown to be present in both the Auger and autoionisation processes. The satellites appearing in the experimental spectra are interpreted as autoionisation lines.

As a result of collisions between excited Hg atoms in the 3P1 and 3P0 states positive molecular ions Hg2+ and electrons are produced. From the observed saturation currents the associative ionization cross section is found to be about 5×10−14 cm2, which compares favourably with theoretical estimates. Using this result the cross section for the reverse process, dissociative recombination into excited atoms, has been determined thermodynamically. The corresponding recombination coefficient agrees with that found in earlier experiments in a decaying Hg plasma.