Mass Scale Production Research Articles

Analysis and comparison of performance and emissions of an internal combustion engine fuelled with petroleum diesel and different bio-diesels

The performance and emissions of an internal combustion engine (ICE) engine fuelled with two bio-diesels are experimentally measured and analysed according to ISO 8178 standard and compared with that of the petroleum diesel. Two types of bio-diesel, type A and type B (defined in Section 1) with their blends of B5, B10, B20, B50 and B100 are tested and analysed. This study found that the performance of both bio-diesel fuels reduces with increasing blend ratio, with a torque decrease of 5% for both bio-diesels, and a fuel consumption increase of 7–10%. This can be attributed to the lower energy content of bio-diesel when compared with petroleum diesel. For both the bio-diesels, some emissions were found to be higher than petroleum diesel, while some were lower. Nitrogen Oxide (NOx) emissions decreased by 14% for bio-diesel A, but increased by 17% for bio-diesel B. Carbon monoxides (CO) emissions were significantly reduced for both bio-diesel A and B, with reductions of 58% and 27% respectively. Hydrocarbon (HC) emissions were found to increase with increasing blend ratio for both bio-diesels, with an increase of 10% for bio-diesel A and 80% for bio-diesel B. Lastly, Carbon dioxides (CO2) emissions were found to increase, with an increase of 6% for bio-diesel A and 18% for bio-diesel B. The study clearly found that each of the bio-diesels has different scale of effect on ICE performance and emissions and hence, it is essential to test bio-diesels before it can be recommended for mass scale production and for commercial use in ICE. However, the study indicates that the two major pollutant gas emissions are generally reduced when using bio-diesel, therefore bio-diesel can be considered to be a more environmentally friendly, secure and renewable approach of obtaining energy in the long run.

Asymbiotic seed germination and in vitro seedling development of Cymbidium aloifolium (L.) Sw.: a multipurpose orchid

Cymbidium aloifolium is a multipurpose economically important epiphytic orchid grows on tree trunk in the primary forests. Its population in natural habitat is downsized due to different anthropogenic activities. A successful attempt was made for asymbiotic immature embryo culture and in vitro mass scale production of plantlets. For successful culture initiation seed pods of various developmental ages, various nutrient media, sucrose concentrations, different quality and quantity of plant growth regulators were surveyed. Immature embryos of 9 months after pollination was successfully germinated on MS medium containing sucrose (2%) (w/v) and α-naphthalene acetic acid (NAA) and benzyl adenine (BA) (3 and 6 μM respectively in combination) within 45 days of culture where 90% germination was recorded. The germinated seeds formed PLBs on the optimum germination medium within two passages. The protocorm like bodies (PLBs) differentiated into rooted plantlets within 3 weeks on regeneration medium containing sucrose (3%), casein-hydrolysate (0.1 gl−1) and BA 3 μM. Amongst the three media studied, optimum regeneration was registered on MS medium where as many as 12 shoot buds developed per explants per subculture of 4 weeks duration. The well rooted plantlets of 6–7 cm long with 3–4 roots were hardened in vitro 3–4 weeks before they were transferred to potting mix. The potted plants were exposed to full sunlight periodically and watered at regular interval. About 70–80% transplants survived after 2 months of potting.

Improvement of the designs of steam turbines produced by the ZAO ural turbine works

We present fundamentally new design solutions aimed at making the steam turbines produced by the ZAO Ural Turbine Works more reliable, economically efficient, maneuverable, and suitable for massscale production.

In vitro propagation of Coscinium fenestratum (Gaertn.) Colebr. (Menispermaceae) - an endangered medicinal plant

Abstract: Coscinium fenestratum (Gaertn.) Colebr. is an important medicinal plant belonging to the family Menispermaceae. Multiple shoots were formed from epicotyl explants on Murashige and Skoog (MS) medium supplemented with 1.0 μM kinetin (Kin) and 0.25 μM 2,4-Dichlorophenoxy acetic acid (2,4-D). A maximum of five shoots were obtained from one explant in a 75-day culture period. The effect of subsequent subcultures on shoot formation was also studied. Repeated subculture favoured the increase in shoot length and the number of shoots per explant in the media containing Kin and 2,4-D. Higher concentrations of either cytokinin used: butyric acid (BA) or Kin causes stunting of multiple shoots with small and narrow leaves. After 100% in vitr o rooting was obtained in half-strength MS supplemented with 2.5 μM Indole-3-butyric acid (IBA), plantlets were transferred to ex vitro conditions. Following a 15-day in vitro rooting period and 12 days of ex vitro acclimatization, 66.7% of the plantlets were established in the compost beds for another two months to improve the leaf size and then transferred to the field with 100% survival rate. This protocol has the potential for use as a tool for mass scale production of planting material. Keywords: Conservation, Coscinium fenestratum , Menis- permaceae, micropropagation. Doi: 10.4038/jnsfsr.v38i4.2648 J.Natn.Sci.Foundation Sri Lanka 2010 38 (4): 219-223

Small Molecule Solution-Processed Bulk Heterojunction Solar Cells

Although most research in the field of organic bulk heterojunction solar cells has focused on combinations of a p-type conducting polymer as a donor and a fullerene-based acceptor, recent work has demonstrated the viability of solution-processed heterojunctions composed entirely of molecular solids. Molecular solids offer potential advantages over conjugated polymer systems in terms of easier purification, amenability to mass-scale production and better batch-to-batch reproducibility. This article reviews the major classes of molecular donors that have been reported in the literature in the past several years and highlights some of key considerations in molecular heterojunction design compared to polymer-based bulk heterojunctions.

A simple recipe for an efficient TiO2 nanofiber-based dye-sensitized solar cell

Development of highly efficient dye-sensitized solar cells (DSSCs) with good photovoltaic parameters is an active research area of current global interest. In this article, we provide a simple recipe for the fabrication of electrospun TiO(2) nanorod-based efficient dye-sensitized solar cell using a Pechini-type sol. The Pechini-type sol of TiO(2) nanofibers produces a highly porous and compact layer of TiO(2) upon doctor-blading and sintering without the need for an adhesion and scattering layers or TiCl(4) treatment. The best nanofiber DSSCs with an area of ~0.28 cm(2) shows an efficiency of ~4.2% under standard test conditions (100 mW/cm(2), 25°C and AM1.5 G) and an incident photon-to-electron conversion efficiency (IPCE) of ~50%. Impedance measurements show lower charge transfer resistance that improved the fill factor. We believe that simple approaches such as the present one to develop nanofiber DSSCs would open up enormous possibilities in effective harvesting of solar energy for commercial applications, considering the fact that electrospinning is a cost-effective method for the mass scale production of nanofibers and nanorods.

Preparation of micro-sized and uniform spherical Ag powders by novel wet-chemical method

A novel wet-chemical method was presented for the preparation of the micro-sized and uniform spherical Ag powders on a mass-production scale. The well-defined particles were synthesized by mixing the iron(II) sulfate heptahydrate solution with silver nitrate solution directly by high-speed stirring at room temperature. It is found that a large number of micro-sized and uniform spherical particles with rough surfaces are obtained. The mass ratio of iron(II) sulfate heptahydrate to silver nitrate greatly affects the shape of particles, and when it is relatively low, spherical particles cannot be obtained. The reaction temperature has a great impact on the particle size. As the reaction temperature increases from 8 to 15 °C, the mean diameter of particles decreases from 3.5 to 1.6 (m. The additive n-methyl-2-pyrrolidone improves the surface smoothness and compactness of the particles while the particle size is kept unchanged. Scanning electron microscopy, X-ray diffractometry and energy dispersive X-ray analysis were used to characterize the particle products.

Directed Self-Assembly: Expectations and Achievements.

Nanotechnology has been a revolutionary thrust in recent years of development of science and technology for its broad appeal for employing a novel idea for relevant technological applications in particular and for mass-scale production and marketing as common man commodity in general. An interesting aspect of this emergent technology is that it involves scientific research community and relevant industries alike. Top–down and bottom–up approaches are two broad division of production of nanoscale materials in general. However, both the approaches have their own limits as far as large-scale production and cost involved are concerned. Therefore, novel new techniques are desired to be developed to optimize production and cost. Directed self-assembly seems to be a promising technique in this regard; which can work as a bridge between the top–down and bottom–up approaches. This article reviews how directed self-assembly as a technique has grown up and outlines its future prospects.

A coupling of rapid crystallization and plastic consolidation as a method for mass scale production of bulk submicrocrystalline aluminum alloys

AbstractRapid crystallization is a well‐known method for production of ultrafine‐grained metallic materials using the overcooling effect. Unfortunately, this method provides material in dispersed form with very limited dimensions of individual particles, which must be consolidated to bulk form for engineering use. To prevent destabilization of ultrafine‐grain structure of polycrystalline particles the consolidation process should to be quick enough and must be conducted at reasonably low temperatures. Such reasons suggest the process of plastic consolidation. In this process plastic deformation of individual particles develops new surfaces in status nascendi, which is able to create strong bonds between collectively deformed particles of dispersed materials and converts the powder to the bulk form. The plastic consolidation by isothermal extrusion is the agglomeration process of plastically deformable particles without involving diffusion effects. Bulk materials with no measurable porosity are the product of this process, in which the character of interaction among individual particles of powder shows similar character to interaction at grain boundaries in polycrystalline metals.

Properties of ZnO:Ga Transparent Conducting Film Fabricated on O2 Plasma-Treated Polyethylene Naphthalate Substrate

Transparent conducting oxide (TCO) films are widely used for optoelectronic applications. Among TCO materials, zinc oxide (ZnO) has been studied extensively for its high optical transmission and electrical conduction. In this study, the effects of <TEX>$O_2$</TEX> plasma pretreatment on the properties of Ga-doped ZnO films (GZO) on polyethylene naphthalate (PEN) substrate were studied. The <TEX>$O_2$</TEX> plasma pretreatment process was used instead of conventional oxide buffer layers. The <TEX>$O_2$</TEX> plasma treatment process has several merits compared with the oxide buffer layer treatment, especially on a mass production scale. In this process, an additional sputtering system for oxide composition is not needed and the plasma treatment process is easily adopted as an in-line process. GZO films were fabricated by RF magnetron sputtering process. To improve surface energy and adhesion between the PEN substrate and the GZO film, the <TEX>$O_2$</TEX> plasma pre-treatment process was used prior to GZO sputtering. As the RF power and the treatment time increased, the contact angle decreased and the RMS surface roughness increased significantly. It is believed that the surface energy and adhesive force of the polymer surfaces increased with the <TEX>$O_2$</TEX> plasma treatment and that the crystallinity and grain size of the GZO films increased. When the RF power was 100W and the treatment time was 120 sec in the <TEX>$O_2$</TEX> plasma pretreatment process, the resistivity of the GZO films on the PEN substrate was <TEX>$1.05\;{\times}\;10^{-3}{\Omega}-cm$</TEX>, which is an appropriate range for most optoelectronic applications.

Corrosion resistance characteristics of stamped and hydroformed proton exchange membrane fuel cell metallic bipolar plates

Metallic bipolar plates have several advantages over bipolar plates made from graphite and composites due to their high conductivity, low material and production costs. Moreover, thin bipolar plates are possible with metallic alloys, and hence low fuel cell stack volume and mass are. Among existing fabrication methods for metallic bipolar plates, stamping and hydroforming are seen as prominent approaches for mass production scales. In this study, the effects of important process parameters of these manufacturing processes on the corrosion resistance of metallic bipolar plates made of SS304 were investigated. Specifically, the effects of punch speed, pressure rate, stamping force and hydroforming pressure were studied as they were considered to inevitably affect the bipolar plate micro-channel dimensions, surface topography, and hence the corrosion resistance. Corrosion resistance under real fuel cell conditions was examined using both potentiodynamic and potentiostatic experiments. The majority of the results exhibited a reduction in the corrosion resistance for both stamped and hydroformed plates when compared with non-deformed blank plates of SS304. In addition, it was observed that there exist an optimal process window for punch speed in stamping and the pressure rate in hydroforming to achieve improved corrosion resistance at a faster production rate.

Individual nanocomposite sheets of chemically reduced graphene oxide and poly(N-vinyl pyrrolidone): preparation and humidity sensing characteristics

Individual nanocomposite sheets of chemically reduced graphene oxide (CRG) and poly(N-vinyl pyrrolidone) (PVP), namely CRG/PVP, have been fabricated through a simple one-pot procedure. The structure and composition of the as-prepared CRG/PVP sheets were complementarily characterized using solid-state 13C NMR, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and other spectroscopic measurements, demonstrating that the PVP molecules were chemically grafted on the CRG surfaces. The electrical conductivity of the individual CRG/PVP sheets was measured at different levels of relative humidity (RH) using a conductive atomic force microscopy (CAFM) system, revealing that the electrical conductivity of a CRG/PVP sheet is sensitive to RH variation with a response time of a few seconds. Given the easy mass scale production and improved electrical conductivity, we envisage that the CRG/PVP nanocomposite sheets should have a broad spectrum of applications in electrical conductivity based sensors.

Sex separation strategies: past experience and new approaches

The success of the sterile insect technique (SIT) and other genetic strategies designed to eliminate large populations of insects relies on the efficient inundative releases of competitive, sterile males into the natural habitat of the target species. As released sterile females do not contribute to the sterility in the field population, systems for the efficient mass production and separation of males from females are needed. For vector species like mosquitoes, in which only females bite and transmit diseases, the thorough removal of females before release while leaving males competent to mate is a stringent prerequisite. Biological, genetic and transgenic approaches have been developed that permit efficient male-female separation for some species considered for SIT. However, most sex separation methods have drawbacks and many of these methods are not directly transferable to mosquitoes. Unlike genetic and transgenic systems, biological methods that rely on sexually dimorphic characters, such as size or development rate, are subject to natural variation, requiring regular adjustment and re-calibration of the sorting systems used. The yield can be improved with the optimization of rearing, but the scale of mass production places practical limits on what is achievable, resulting in a poor rearing to output ratio. High throughput separation is best achieved with scalable genetic or transgenic approaches.

Beneficial uses of probiotics in mass scale production of marine ornamental fish

Mass scale culture of marine ornamental fish is facing many problems caused by pathogenic microorganisms. The accumulation of unconsumed feed and bad water quality influence the growth of pathogenic forms of the Vibrio sp. To avoid these problems probiotics are used as an alternative agent in vitro for efficacy based on the inhibition of growth of pathogenic Vibrio sp and also it decreased the concentrations of ammonium, nitrite, nitrate and phosphate ions. The present study revealed that after the use of probiotics in experimental tank the beneficial microbial load is drastically increased but decreased the level of pathogenic Vibrios. The bacterial population changed during every sampling. THB in the experimental tank before the application of probiotics ranged from 2.39 x 103 to 4.82 x 104. After the application of probiotics, THB population varied between 4.21x 106 and 7.43 x 107. In the control tank, THB count was found to be between 5.28x 103 and 2.1 x 105, but Vibrio load was high. Vibrio sp counts ranged from 6.82 x102 to 9.21 x 103 CFU/ml in the experimental tank prior to application of probiotics. After the application of probiotics, Vibrio population varied between 1.62 X102 and 3.96 x 102 CFU/ml. In the control tank, Vibrio count was found to be between 8.56 x102 and 2.1 x 104 CFU/ml. Key words: Probiotics, ornamental fish, disease.

Micro-injection moulding of polymer microfluidic devices

Microfluidic devices have several applications in different fields, such as chemistry, medicine and biotechnology. Many research activities are currently investigating the manufacturing of integrated microfluidic devices on a mass-production scale with relatively low costs. This is especially important for applications where disposable devices are used for medical analysis. Micromoulding of thermoplastic polymers is a developing process with great potential for producing low-cost microfluidic devices. Among different micromoulding techniques, micro-injection moulding is one of the most promising processes suitable for manufacturing polymeric disposable microfluidic devices. This review paper aims at presenting the main significant developments that have been achieved in different aspects of micro-injection moulding of microfluidic devices. Aspects covered include device design, machine capabilities, mould manufacturing, material selection and process parameters. Problems, challenges and potential areas for research are highlighted.

Aerosol-assisted Fabrication of Porous Silica Spheres with a Hierarchical Pore System through Multicomponent Assembly

Abstract Hierarchical porous silica spheres with a trimodal pore system are prepared through multicomponent assembly, which is a facile one-pot fabrication and can best be employed for industrial mass-scale production.

On the way to mass-scale production of perfect bulk diamonds

Diamonds are hard. Humans have known that for ages. This hardness encompasses not only mechanical hardness, but also chemical, electrical, optical, and structural hardness (1). Diamonds are hard to cut, and shaping them requires a complex technology. Diamonds are chemically inert and, because of this, they are not processed chemically. Diamonds are resistant to electrical fields and, as an electronic material, they can work in the highest electric fields that solids can withstand. They are hard structurally and, because of this, they do not allow diffusion, they are immune to radiation, and they possess a stable defect structure.

Ultrasonic Nanoimprint on Poly(ethylene terephthalate) at Room Temperature

We have developed a new nanoimprint lithography (NIL) technology employing ultrasonic vibrations generated by a magnetostriction actuator where the process does not require any heating or use of ultraviolet light. In this work, a mold was mounted onto an upper loading stage using a negative-type resist. The mold pattern was then run through “push-into and pull-away” cycles on a molding material by applying longitudinal ultrasonic vibrations. For the molding material, poly(ethylene terephthalate) (PET) was selected because among engineering plastics its glass transition temperature is relatively low. Using this technique we succeeded in imprinting on PET at room temperature and made significant improvement in the throughput. The relationship between the depth of imprinted patterns and the contact force, or the contact time, was investigated by imprint experiments that employed an electroformed-Ni mold with convex patterns. The result of the experiment showed that, in working with ultrasonic NIL, the best contact force and the best contact time depend on the size of the pattern. The ultrasonic NIL technology has the potential of becoming a key technology for carrying out tasks on the scale of mass production.

Effect of Aeration on Production of Anticancer Lignans by Cell Suspension Cultures of Linum album

The effects of aeration within the range of 0.2-0.5 vvm on transformed and high yielding cell cultures of Linum album were investigated in a 5-L stirred tank bioreactor equipped with low shear Setric impeller. The kinetics of cell growth, substrate utilization, and production of lignans, namely, podophyllotoxin and 6-methoxypodophyllotoxin, were established. Maximum biomass of 23.2 g/L and lignan accumulation levels of 176.3 mg/L podophyllotoxin and 10.86 mg/L 6-methoxypodophyllotoxin were obtained with initial air flow rate of 0.3 vvm. Specified oxygen demand of cells was estimated to be 1.35 g O(2)/g biomass. The optimum oxygen transfer coefficient was found to be 16.7 h(-1) (,) which corresponded to aeration rate of 0.3 vvm. The effect of minimum dissolved oxygen (DO) concentration was investigated with respect to biomass and lignan production by comparing identically aerated and agitated bioreactor cultivations at dissolved oxygen concentrations of 10%, 30%, and 50%. Cell growth and podophyllotoxin accumulation were not affected significantly at these DO levels, but 6-methoxypodophyllotoxin production was enhanced when cells were cultivated at 30% DO level. The maximum volumetric productivities of 18.2 mg/L day and 3.2 mg/L day for podophyllotoxin and 6-methoxypodophyllotoxin, respectively, were obtained. These results establish the key role of oxygen on mass scale production of anticancer lignans by cell cultures of L. album. It may serve as a suitable parameter for scale-up.

Cloning, sequencing, overexpression and characterization of l-rhamnose isomerase from Bacillus pallidus Y25 for rare sugar production

The L-rhamnose isomerase gene (L-rhi) encoding for L-rhamnose isomerase (L-RhI) from Bacillus pallidus Y25, a facultative thermophilic bacterium, was cloned and overexpressed in Escherichia coli with a cooperation of the 6xHis sequence at a C-terminal of the protein. The open reading frame of L-rhi consisted of 1,236 nucleotides encoding 412 amino acid residues with a calculated molecular mass of 47,636 Da, showing a good agreement with the native enzyme. Mass-produced L-RhI was achieved in a large quantity (470 mg/l broth) as a soluble protein. The recombinant enzyme was purified to homogeneity by a single step purification using a Ni-NTA affinity column chromatography. The purified recombinant L-RhI exhibited maximum activity at 65 degrees C (pH 7.0) under assay conditions, while 90% of the initial enzyme activity could be retained after incubation at 60 degrees C for 60 min. The apparent affinity (K(m)) and catalytic efficiency (k(cat)/K(m)) for L-rhamnose (at 65 degrees C) were 4.89 mM and 8.36 x 10(5) M(-1) min(-1), respectively. The enzyme demonstrated relatively low levels of amino acid sequence similarity (42 and 12%), higher thermostability, and different substrate specificity to those of E. coli and Pseudomonas stutzeri, respectively. The enzyme has a good catalyzing activity at 50 degrees C, for D: -allose, L-mannose, D-ribulose, and L-talose from D-psicose, L-fructose, D-ribose and L-tagatose with a conversion yield of 35, 25, 16 and 10%, respectively, without a contamination of by-products. These findings indicated that the recombinant L-RhI from B. pallidus is appropriate for use as a new source of rare sugar producing enzyme on a mass scale production.