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The motivation behind this study is to fabricate novel nanocomposite materials with stronger dielectric characteristics to be applied in electronic devices. The chemical oxidative polymerization technique was employed to fabricate the PET/(PPy-Ag) polymer composite films. These films consist of silver nanoparticles (AgNPs) and polypyrrole (PPy), and the blend (PPy-Ag) is then deposited on the polyethylene terephthalate (PET) substrate. The choice of method depends on the desired application, the properties of the polymer and the level of nanoparticle dispersion required. The characterization methods, Fourier-transform-infrared spectroscopy (FTIR) and energy dispersive X-ray (EDX) were utilized in this study. The EDX data show that the PET/(PPy-Ag) is successfully fabricated with elements C, N, O and Ag, with weight ratios of 15.76%, 8.92%, 65.88% and 9.44%, respectively. The influence of (PPy-Ag) on the conductivity and surface wettability of PET was evaluated. The surface-free energy and adhesion work were determined using contact angle measurements. The surface-free energy increased from 41.64 to 60.24mJ/m² and the water adhesion work increased from 98.78mJ/m² for PET/(PPy-Ag)-1 to 121.01mJ/m² for PET/(PPy-Ag). Moreover, the conductivity enhanced from $6.2\times 10^{-9}$S.cm${}^{-1}$ for PET to $2.4\times 10^{-6}$S.cm${}^{-1}$ for (PPy-Ag)/PET. By modifying the properties of the composite PET/(PPy-Ag), the results demonstrated that the fabricated composite can be used as an electronic and industrial device.

Single-cell arched beams show excellent energy absorption performances under transverse loads. However, the fabrication of arched beams with a perfect arc segment is relatively tricky and expensive by casting or additive manufacturing technology. In this paper, a simple three-point bending method is proposed for the fabrication of single- or multi-cell arched beams. Although indentation or concave is formed in the central region of arched beams during fabrication, the beams show even better energy absorption performances than the perfect arched beams. Static and dynamic three-point bending tests of the fabricated arched beams are first carried out, and numerical simulations of the fabrication process and the subsequent bending collapse are then performed. The influences of the fabrication factors on the performances of the arched beams are investigated. Arched beams with tube fillers and multi-cell sections can be easily fabricated by the proposed method, and the crashworthiness performances of these fabricated arched beams are significantly improved. In addition, the multi-cell arched beams fabricated by the present method exhibit excellent performances and outperform the arched beams with a perfect arc segment.

This paper presents the experimental characteristics of 3-state n-MOS inverters utilizing Quantum Dot Gate (QDG) FETs. By employing FETs that have quantum dots in the gate region, particularly Si-SiOx cladded quantum dots and Ge-GeOx cladded quantum dots, intermediate states were observed in both variations of the device, both of which using the same architecture and mask set.

Ion implantation is widely utilized in microelectromechanical systems (MEMS), applied for embedded lead, resistors, conductivity modifications and so forth. In order to achieve an expected device, the principle of ion implantation must be carefully examined. The elementary theory of ion implantation including implantation mechanism, projectile range and implantation-caused damage in the target were studied, which can be regarded as the guidance of ion implantation in MEMS device design and fabrication. Critical factors including implantations dose, energy and annealing conditions are examined by simulations and experiments. The implantation dose mainly determines the dopant concentration in the target substrate. The implantation energy is the key factor of the depth of the dopant elements. The annealing time mainly affects the repair degree of lattice damage and thus the activated elements’ ratio. These factors all together contribute to ions’ behavior in the substrates and characters of the devices. The results can be referred to in the MEMS design, especially piezoresistive devices.

This study addressed the preparation of nanocomposites consisting of polyvinyl alcohol (PVA) and titanium oxide (TiO₂) for utilization in optoelectronics technologies. PVA/10%TiO₂ nanocomposite samples with a mean thickness of 0.1mm were created using the solution casting method. The PVA/TiO₂ films are irradiated with oxygen fluences of $0.4\times 10^{17}$, $0.8\times 10^{17}$ and $1.2\times 10^{17}$ ions/cm². The X-ray diffraction (XRD) and FTIR methodologies were employed to investigate the impact of ion bombardment on the structural characteristics and functional groups of PVA/TiO₂ substrates. Diffraction peaks are 20.1° for PVA and 25.4° for TiO₂, indicating the successful PVA/TiO₂ nanocomposite construction. The absorbance (A) of unirradiated and irradiated samples was measured using UV–Vis spectroscopy within a wavelength range of 200–1100nm. Band gaps ($E_g$) were calculated using Tauc’s formula for PVA/TiO₂ films, exhibiting a decrease from 4.56eV for unirradiated PVA/TiO₂ film to 4.16, 3.95 and 3.88eV at ion fluences of $0.4\times 10^{17}$, $0.8\times 10^{17}$ and $1.2\times 10^{17}$ ions/cm², respectively. Furthermore, the Ubrach tail has a rise of 1.23eV for unirradiated PVA/TiO₂ to 1.28eV, 1.4eV and 1.77eV for irradiated films with ion fluences of $0.4\times 10^{17}$, $0.8\times 10^{17}$ and $1.2\times 10^{17}$ ions/cm², respectively. Additionally, following ion irradiation, the PVA/TiO₂ absorption edge $E_e$, which was 3.56eV, decreased to 3.48, 3.37 and 3.23eV, with increasing ion beam fluences. This study demonstrated that the optical behaviors of the PVA/TiO₂ films were altered under bombardment, suggesting their potential applicability in optical devices.

A kind of large-mode-area (LMA) erbium-doped fiber (EDF) is required to get high output power with good beam quality. This new LMA EDF has a multi-layer-core structure which makes the mode area bigger. The key process is deposition of multi-layer-core structure by using modified MCVD to make every layer of the core with different refractive index. Furthermore, the key optical specifications of the fiber are measured. The absorption peak is 10.6 dB/m at 980 nm and 20 dB/m at 1550 nm. The cutoff wavelength is about 1300 nm. The mode field diameter (MFD) is 12.6 μm and 13.2 μm at 1550 nm according to Petermann-2 and Gaussian definitions, respectively. The core diameter is about 12 μm. The MFD of conventional standard EDFs is in a limited range ~5–8 μm, so the experimental result has made a big progress for MFD. Especially, we can improve the parameters of the multi-layer-core structure to get single mode EDF with larger mode area for high power fiber laser.

This paper proposes a switched-capacitor (SC)-based step-down AC–DC power converter with high-frequency feed without rectifier or transformer. The operational principle of the circuits and the design considerations are described. The main advantage of the circuit is that step-down voltage can be achieved in the circuit by simply configuring with cascaded stages, which will be much more convenient to be modular development and easy for replacement and maintenance; the voltage and current stresses of most components are smaller than the conventional converter. Using buffer capacitor to reserve energy, there are no magnetic energy storage elements in the circuits. Weight and size can be further reduced due to high-frequency-power line operation. Zero current switching (ZCS) is achieved by introducing small resonant inductors. Therefore, higher efficiency and power density can be achieved. The performance of the converter has been demonstrated by an experiment with 50 kHz 50 V power feed which is emulated by a signal generator and high-frequency amplifier to prove the concept.

Nano-fluidic devices have great potential in the applications of biology, chemistry, and medicine. However, their applications have been hampered by their expensive or complicated fabrication methods. We present a new and simple approach to fabricate low-cost two-dimensional (2D) nano-mold based on ultraviolet (UV) lithography and wet etching. The influence of UV lithography parameters on the width dimension of AZ5214 photoresist was investigated. With the optimized parameters of UV lithography, the width dimension of photoresist patterns had sharply decreased from microscale to nano-scale. At the same time, the influences of etching time on the over-etching amount of SiO₂ film and nano-mold depth were also analyzed for further reducing the width of nano-mold. In addition, the effect of photoresist mesas deformation on the nano-mold fabrication was also studied for improving the quality of nano-mold. By the proposed method, trapezoid cross-sectional 2D nano-mold with different dimensions can be obtained for supporting varied applications. The minimum nano-mold arrays we fabricated are the ones with the dimensions of 115nm in top edge, 284nm in bottom edge, and 136nm in depth. This method provides a low-cost way to fabricate high-quality and high-throughput 2D nano-mold.

University of Queensland Offers Biotech Scholarship to Indian Students.

Australian Government Contributes $50M to Walter and Eliza Hall Institute.

US Pharmacy Giant MedicineShoppe Opens its First Store in China's ChongQing.

Pall Life Science Sets up Proteomics Center at Bangalore.

Hong Kong and Guangdong Health Experts to Collaborate on Bird Flu Lab Testing.

Taiwan's Vita Genomics, Yang Ming University and India's IGIB Sign Agreement on Liver Disease Research.

Update on Bird flu.

Singapore Scientists Make Discoveries on Stomach Cancer.

US Imalux Corporation Inks Distribution Deals with Beijing Goodwell Company Limited.

Australia's CSL Expansion Facility and Vaccine Market.

India and the US Collaborate on Agriculture.

Korea's Professor Hwang's Fabrication of Embryonic Stem Cell Research.

Cygenics Awarded Another Patent.

In the past few decades, sophisticated machining industries have rapidly improved in order to achieve the required shape of a part within a specific time while also not affecting material properties. Accuracy of machined components in all industries is important. In the case of subassemblies of components, geometrical accuracy of hole is vital. The researchers updated their machinery from time to time from this perspective. In the machining process, environment and time are the vital parameters that are mainly affected, so in this case, the design of experiments that are very useful in the machining region needs to be considered to overcome these challenges. This study aims to analyze the fabrication of hot abrasive jet machining (HAJMing) with different abrasive temperatures using fluidized bed system as well as accomplishment of cutting performance in hot-abrasive jet machining concerning target surface erosion. Additionally, this research study accomplishes the experimental study and computational fluid dynamics (CFD) technique for erosive footprint prediction extent in HAJMing constraints on target surface for intricately shaped tapered holes generation. The use of hot abrasives in the HAJM process has demonstrated an interest in improving cutting performance for material erosion. Moreover, this proposed experimental work contains the manufacturing, design and fabrication of hot abrasive jet machine (HAJM) using commercially available hardware and software. So, the components are manufactured indigenously as per the designed parameters for the purpose of improving the machining performance. Simulation for material erosion mechanism of HAJMing is used to obtain the nature of produced workpiece profile. Additionally, FB-HAJMing also deals with the sustainability assessment under environmental-friendly hot abrasive-assisted machining conditions.

In this study, self-assembled alternating film using poly(diallyldimethylammonium chloride) (PDDAC) and meso-tetrakis(4-carboxyphenyl)porphyrin (MTCP) was prepared as a multilayer deposition on glass substrate. This preparation technique for dye deposition may provide new feasibilities to achieve the manufacture of ultrathin films for nanotechnology application. The deposition films were characterized by UV-vis spectrophotometer and Atomic Force Microscopy (AFM) analysis. The results of UV-vis spectra showed that the absorbance characteristic of the multilayer films linearly increased with an increased number of PDDAC and MTCP bilayers. AFM analysis showed the film surface was relatively uniform and the progressive growth of layers was determined.

Conventional SU-8 lithography process for fabricating microfluidic devices ofthe uses silicon or glass as wafer materials. Since silicon and glass are hard and brittle, drilling fluid access holes or dicing the wafers into individual devies are difficult. We investigated the use of polymethylmethacrylate (PMMA) as a new wafer material. PMMA, an amorphous thermoplastic, was chosen for being easy to drill or cut, biocompatible, transparent, and much cheaper than silicon or glass wafers. Moreover, is thermal expansion coefficient ideally matches that of SU-8. PMMA poorly resists solvents, and has low glass transition temperature (105°C). Thus, the conventional process needed to be modified. The wafer was only cleaned with isopropyl alcohol and deionized water. The baking temperature was lowered to 90°C. In addition, a "base layer" of SU-8, helping to achieve a high quality structural pattern, was coated before coating the actual structural SU-8 layer. A Tesla valve, a non-moving part microfluidic valve, was successfully fabricated in SU-8 using thr presented process,. However, the PMMA wafer bowed ue to the thermal residual during baking steps. Despite the bowing which can be solved by increasing wafer thickness, we conclude that PMMA is a promising wafer material for a SU-8 process.

The structural battery (SB) that uses carbon fibers as anodes is a lightweight composite material battery integrating load bearing and energy storage. However, during usage, diffusion-induced stress may result in structural failure and a reduction in the battery capacity. In this paper, a laminated structural battery (LSB) was fabricated using carbon fiber cloth as an anode and collector and successfully powered LEDs. Then, based on this laminated structure, a multiphysics field model based on electrochemical-mechanical coupling is established for the analysis of complicated diffusion-induced stresses in carbon fibers. Following this model, researchers investigate the electro-chemo-mechanical behaviors and influencing factors of the SB and compare them with those of the lithium-ion battery (LIB). The results show that diffusion polarization in carbon fibers is aggravated by their lower diffusion coefficient, larger radius, and higher discharge rate; in both types of batteries, there is a higher tensile diffusion stress and a higher probability of failure at the surface of the anode active material than in the interior; a more uniform distribution of diffusion-induced stress on the surface of fibers at different locations; when discharging at a high rate, the SB capacity hardly reduces, and the high strength and relatively low diffusion-induced stress in the carbon fiber make it much safer, showing excellent electrochemical performance and resistance to failure due to diffusion-induced stress. This study demonstrates the feasibility of the fabrication and safety of carbon fiber structural batteries, which may potentially offer recommendations for the fabrication and use of novel SBs.

Scaffolds offer a three-dimensional framework supporting cell growth, proliferation, and differentiation of cells which are used to repair and regenerate tissues. Recent advancements in scaffold technology have significantly exploited the field of tissue engineering and regenerative medicine. This comprehensive review provides in-depth exploration of scaffold materials, fabrication techniques, and their recent progress in applications. Composite scaffolds have promising applications in bone and dental tissue regeneration due to their greater mechanical properties and ability to promote cell growth. The inherent crosslinking present in hydrogels allows them to maintain their integrity and three-dimensional structure without dissolving. However, there is a growing interest in smart hydrogels which can respond to changes in their external surroundings like pH, ionic strength, temperature, or specific molecules. dECM scaffold is an alternative potential technique for reconstructing the functional organs/tissues by excluding the cell-associated antigens while maintaining the native ECM compositions like growth factors, basement membrane structural proteins, and GAG’s. The degree of porosity in scaffolds can be increased by various fabrication techniques such as TIPS, SCPL, gas foaming, and freeze drying. GelMA hydrogels have shown promising potential in cell proliferation and tissue regeneration. In addition, graphene and its derivatives have been instrumental in the fabrication of bioactive scaffolds for cartilage regeneration. The introduction of additive manufacturing technologies, specifically 3D bioprinting, has significantly improved the precision and control of scaffold fabrication.

Space telescopes require large aperture primary mirrors to capture High Definition (HD) ground image while orbiting around the Earth. Fairing Volume of launch vehicles is limited and thus the size of monolithic mirror is limited to fairing size and solar panels are arranged within a petal formation in order to provide a greater power to volume ratio. This generates need for deployable mirrors for space use. This brings out a method for designing new deployment mechanism for segmented mirror. Details of mechanism folding strategy, design of components, FE simulations, realization and Lab model validation results are discussed in order to demonstrate the design using prototype.

Flying robots popularly known as drones or UAVs are emerging technologies of the current era. A significant amount of research work has been undertaken in this area in the last few years. Considering the current scenario where aerial vehicles are taking a major part of the market it is important to have an effective and robust design of flying robots. This paper aims to examine the categories of flying robots based on the features that include a range from petite to large and its body structure, wing designs, tail design, propulsion system, and gripper mechanisms along with the associated materials and manufacturing techniques. Again the work is intended to review the respective challenges faced by each category. Mostly the challenges faced by flying robots are design challenges, material selection, and fabrication challenges which are discussed in the paper. In this paper, we have summarized various designs of flying robots developed to date as well as we have focused on major features to be taken care of while designing flying robots. This paper has tried to focus on different design aspects and challenges faced by flying robots so that further research can be carried out to develop effective flying robots in the future.

Magnetic anisotropic particles, including Janus, patchy and multicompartment particles, have been particularly of great interest due to their magnetic response and anisotropy potential application in a wide variety of fields. Some strategies and techniques have been used to fabricate magnetic anisotropic particles. In this chapter, one of the main intension is to impart information about achievements on fabrication strategies and techniques of magnetic anisotropic particles in the last several years. A special emphasis will be made on several facial and scalable techniques. Some applications of these magnetic anisotropic particles are also introduced.

This paper presents the experimental characteristics of 3-state n-MOS inverters utilizing Quantum Dot Gate (QDG) FETs. By employing FETs that have quantum dots in the gate region, particularly Si-SiOx cladded quantum dots and Ge-GeOx cladded quantum dots, intermediate states were observed in both variations of the device, both of which using the same architecture and mask set.

This article gives an introduction to the principles and practices of high-resolution electron-beam-induced deposition (EBID). In EBID, a small focused electron beam is used to locally dissociate a precursor onto the surface of a substrate giving rise to a small deposit. Recently it has been discovered that the size of the deposited structure can be as small as one nanometer allowing EBID to be used to fabricate very small nanostructures of arbitrary shape. EBID provides an alternative to more traditional fabrication methods such as electron beam lithography (EBL) and ion beam induced deposition (IBID). EBID is a direct write technique requiring no pre-deposited resist or development and it can be applied to planar and nonplanar surfaces. This article reviews all aspects of the technique including instrumentation, gas-solid reactions, electron-beam specimen interaction, deposition parameters and deposit composition. Special attention is devoted to factors that must be understood and controlled in order to achieve a resolution of 1 nm. Examples of very small nanostructures fabricated by performing EBID with high-energy subnanometer focused electron beams (200 kV) are demonstrated. The chapter compares and contrasts EBID with other fabrication techniques and discusses current and future applications for the technique.

Directional short fibre reinforced Li-Al-Si (LAS) glass-ceramic matrix composites (GCMC) were fabricated by hot pressing at 1450°C. Effect of different fibre volume on the properties of composites was studied. R-curves for composites were investigated using a simple compliance method. A remarkable change in the mechanical properties of GCMC was observed by adding short carbon fibre. Fracture toughness, the crack resistance to crack propagation (R-curve behaviour) and the fracture strength showed considerable improvement. Study shows that improvement in crack resistance was attributed to the extensive interaction of cracks with the short fibres. Composites with 30% volume of fibre showed the best crack-growth resistance. Based on microstructural observations, multiple matrix cracks were found to be arrested in matrix around fibre. Fractures observed include multiple matrix cracking (similar to microcracking) crack branching and crack deflection in crack frontal zone.